Estimation of suspended sediments in hyper-concentrated rivers is prime important as it is highly desired in design and operation of hydraulic structures. In this study the application of Multiquadric basis function neural network for prediction of suspended sediment of a hyper-concentrated river was investigated. Five years daily time series data of discharge and suspended sediments from 1992 - 1996 at Bidor River in Perak, Malaysia was used to develop the prediction model. Several trials were made to investigate the appropriate number of hidden neurons. Performance of the model was evaluated by comparing the observed and predicted sediments with perfect line of agreement. Furthermore, root mean square error and coefficient of efficiency were also used as performance statistical measures for the model. The results showed that the model successfully predicted the suspended sediments with minimum error of (RMSE = 9.06, MAE = 6.0) and highest efficiency of (CE = 0.94). The performance of the model with previous models was also comparable. The results suggested the suitability of Multiquadric basis function neural network for modeling suspended sediments of hyper-concentrated river.

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Drag reduction is introduced by Toms, using polymers and surfactants as drag reducing agents. This technique is greatly applicable in industries and researches nowadays. Insoluble Nano-powder additives, in the present research, are introduced to enhance the flow of liquid in microchannel. Investigation on the effect of variable concentration (100 to 500 ppm) of three different sizes (7 nm, 200-300 nm and 500-700 nm) Fumed Silica (SiO2) with 100 µm micro-channels by varying the flow rate, using syringe pump, on drag reduction is carried out. Higher concentration of Nano-powder solution has a positive effect on drag reduction, meanwhile, bigger particle size and addition of surfactant in Nano-powder solution has a negative effect on the performance of drag reduction. Maximum drag reduction up to 56% is achieved by using 500 ppm of 200-300 nm fumed silica. This breakthrough discovery may help to speed up the improvement in medical field.

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Palm Oil Mill Effluent (POME)’s nutrient composition and its ensuing removal from the wastewater is rarely reported in contrast with organics removal. Thus, the efficiency of several Industrial Effluent Treatment Systems (IETS) in nutrient removal are studied. Many laboratory- and full-scale studies have been constructed to examine the effectiveness of nutrient removal with a single technology. Therefore, this paper observed their efficiency after several unit processes were combined to perform, which generally occurred in the full-scale IETS. Total Nitrogen (T-N), Ammoniacal Nitrogen (A-N), and Total Phosphorus (T-P) were nutrient parameters investigated. IETS-3 with highest nutrient removal efficiency were 92.5% T-N, 94.5% A-N, and 93.5% T-P, which highlighted positive combination of ponding system, anaerobic digesters and extended aeration coupled with fixed packing in activated sludge aeration tank. Removal of biological nutrients need to move forwards with cradle-to-cradle waste management methodologies, which focus on sustainable recovery of essential nutrients via operative technologies.

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For fast assessment of defects in conductive materials, Eddy current testing is a most widely non-destructive testing (NDT) evaluation methods utilized in industry, especially in oil and gas, aircraft, nuclear and coating industries. Experimental studies of eddy current testing have emerged as an important approach alongside numerical modeling. This paper focus on investigating the defect signal characteristics of carbon steel pipe weld coating inspection using different frequency eddy current testing. The optimum frequency of carbon steel pipe weld coating is verified. Tests have been conducted utilizing positive and negative scanning method with frequency between 10 kHz to 100 kHz. Artificial defect use of this test is the horizontal affected zone (HAZ), centre line and transverse crack. Experimental results showed the frequency can be impression to the amplitude and phase angle eddy current testing signal. The optimum frequency for carbon steel weld plate is 100 kHz.

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The adsorption capacity of the activated carbon can be increased by introducing the amine group on the surface of the adsorbent. Modified rice husk activated carbon with different concentration and mixture ratio were prepared using wet impregnation method with alkanolamine. The adsorbents obtained were characterized by X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Field Emission Scanning Electron Microscopy (FESEM). From XRD analysis, the diffraction angles around 21.66° to 22.18° were linked for pyrazole, ethanolamine and diethanolamine which prove the presence of hydrocarbon and amine on the activated carbon surfaces. The presence of amide functional groups in FTIR analysis at 3288 cm-1 and 1651 cm-1 band proved that there was a reaction occurred between carboxyl groups on the activated carbon surfaces with amine bond. For FESEM analysis, it was shown that the morphology of the non-modified activated carbon contains many pores on its surface while the pores on the modified activated carbon were covered with alkanolamines according to the selected concentrations.

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This study is the groundwork on the ability of nano-sieve technique in the recovery of water soluble agarwood marker compounds from agarwood hydrosol. To achieve this purpose, a polypiperazine (PPA) based nanofiltration (NF) membrane was used. The effectiveness of this membrane on the separation of agarwood marker molecules was analysed and FTIR results showed that most of marker compounds (i.e. agarospirol, jinkohol, jinkoh eremol and khusenol) has been successfully separated from the aqueous agarwood. However, the performance of the membrane in terms of flux and permeability is quite low, which is 23.30 L/m².h, with 6.76 L/m².h.bar, respectively. These initial findings will be used as the forecast to improve the future development of NF membrane, specifically ‘tailor-made’ for the large scale production of agarwood marker compounds.

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In this research, Microwave Assisted Hydrodistillation (MAHD) was used to extract essential oil from Cinnamomum Cassia (cinnamon). The effect of different parameters, such as water to raw material ratio (6:1, 8:1 & 10:1), microwave power (200 W, 225 W & 250 W) and extraction time (30 min, 60 min, 90 min, 120 min & 150 min) on the extraction yield and its major constituents were investigated. The essential oil was analysed by gas chromatography/ mass spectrometric (GC-MS) to evaluate the effect of extraction method on the content of its main constituent which was trans-Cinnamaldehyde. The optimum condition was found at water to raw material ratio of 8:1, microwave power of 250 W and extraction time of 90 min and the yield obtained under this condition was about 2.55%. The result obtained from GC-MS analysis revealed that the use of microwave irradiation did not adversely influence the composition of the essential oil. The main constituents found through MAHD was more desirable in terms of quality and quantity when compared to the conventional methods. The results obtained herein suggest that MAHD method could serve as a suitable and effective method for the extraction of essential oil from Cinnamomum Cassia (cinnamon).

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Beta-carotene is known to have a high demand in food industry which has made global industry to face challenges especially in fulfilling customers’ requirement that are looking for ‘‘environment friendly’’ and natural products. This has opened up wide opportunities in utilizing crude palm oil (CPO) and oil palm waste (OPW) as natural sources of beta-carotene. Thus, present study explains recovery of beta-carotene from CPO and OPW of palm pressed fiber (PPF) and empty fruit bunch (EFB). Initially, crude oil from solid OPW samples was extracted by soxhlet extraction. Then, recovered oil from both PPF and EFB along with CPO were used to extract palm carotene. Extraction of beta-carotene from CPO and OPW were performed by using soxhlet adsorption method. High performance liquid chromatography (HPLC) analysis revealed beta-carotene as a major carotene in extracted samples. Results obtained indicated that 3790 ppm of beta-carotene extracted from CPO, 1414 ppm from PPF and 702 ppm from EFB by this soxhlet adsorption method.

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Phase inversion technique has been utilized to prepare Poly (vinylidene fluoride-co-hexafluoropropylene) PVDF-co-HFP, hollow fiber membranes. Polyvinylpyrrolidone (PVP) with 9 wt. %. added as a pore former additives to the polymer dope solution. Characteristics of the PVDF-co-HFP hollow fiber membrane with / without PVP particles have been studied. It was found that the membrane prepared without PVP additives has a low porosity and a high contact angle. Existence the PVP additives of 9 wt. % causing the increase of the membrane porosity by 28 %.Whilst increase PVP content resulting in decrease of membrane hydrophobicity. MD experiment was done using a direct contact membrane distillation (DCMD) configuration as crucial test to investigate performance of product PVDF-co-HFP hollow fiber membrane. Increase the amount of PVP to 9 wt. % in dope solution, this in turn leads to an increased the permeate flux from of 4.5 to 15.8 Kg/m2.h at 70 oC The effect of operating conditions such as feed temperature, concentration of feed solution and permeate flow pattern on the performance flux of the hollow fiber membranes were studied.

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The increasing demand of herbal based product has created great opportunities for global marketing. Labisia pumila contains phenolic compounds and it has been proven to have multiple biological effects, such as high antioxidant properties and anti inflammatory activity. The gallic acid (3,4,5-Trihydroxybenzoic acid) is phenolic compounds that exist in Labisia Pumila. Therefore, it is vital to identify the best extraction technique to maximize the performance of the process. Recently, ultrasound-assisted extraction (UAE) widely reported for the extraction of medicinal plants and herbs due to its economic and green technology. The influence of several parameters on the extraction of Labisia pumila were investigated : extraction time (1-8 hours), temperature (40,50,60, and 80 °C) , and sonication (40% duty cycle and without sonication) with solvent-to-sample ratio (1:10). The power intensity at 8.66 W/cm2 was implemented using ultrasonic processor Q700 (700 watts, 20kHz) provided by QSonica, Newtown, U.S. The study was found that, the gallic acid extract increased with increasing temperature up to 50°C and 6 hours. Result indicated the extraction of gallic acid may occur to a certain level and then began to declined due to decomposition of the compound. The highest improvement by ultrasound-assisted extraction was at 50°C by 2.26 fold. It can be concluded that, sonication was improved the extraction of bioactive constituents yield without any chemical aid.

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Ficus deltoidea or Mas cotek is one of the most popular plant herbs that have been widely used traditionally as postpartum treatment and health tonic. Preliminary or existing extraction method has been used to extract the plant herbs that have low productivity range. This method however can still produce the desired products, but the work can be laborious and not efficient in large scale processing. Besides, the sample preparation has no evidence in advances because obtaining such extraction products at sufficient concentrations usually involves extraction with large amounts of organic solvents and toxic, followed by evaporation. Production of Vitexin from Ficus deltoidea extraction under various sonication regiments is reported. Batch extractions were carried at low intensity sonication (8.66 W cm^-2 sonication intensity at the sonotrode tip) using 10%, 20% and 40% duty cycles. (A duty cycle of 10%, for example,wasequivalent to sonication for 1 s followed by a rest period (no sonication) of 10 s.) The extracts were compared with those obtained by conventional boiling extraction, in terms of bioactive constituents yield and chemical composition. In the aqueous (conventional) extracts, the actual percentage weight of Vitexin varied in the range 0.122 ± 0.013 ~ 0.386 ± 0.018 (%w/w) compared to sonicated extracts with 2-fold increases at a range of 0.127 ± 0.001 ~ 0.738 ± 0.050 (%w/w) after 8 hours of extraction with sample-to-water ratio of 10:1 (g/ml) at 50, 70 and 100°C. Both ultrasonic-assisted and aqueous extracts were characterized and standardized by HPLC-diode array detector using a pharmacologically active marker, Vitexin. The experimental values under optimal conditions were in good consistent with the predicted values, which suggested that ultrasonic-assisted extraction (UAE) is more efficient process as compared to conventional boiling extraction (AE). It recommends that ultrasound extraction of F. deltoidea leaves is substantially feasible to replace the traditional time-consuming and low efficiency preparation procedure in the future modernized and commercialized manufacture of this highly valuable herbal medicine.

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A numerical method of predicting the turbulent mixing process of a treated sewer disposed from a marine outfall is described. The momentum equations for the sea water mixed with treated water of small salinity and warmer temperature are solved numerically together with the equation of the concentration of the treated water. The basic method is a Large Eddy Simulation (LES) formulated on a fixed rectangular grid where boundaries are approximated by Immersed Boundary (IB) method. The sub-grid effects of the unresolved fluctuations of velocity and the concentration fields are expressed by the eddy viscosity and eddy diffusivity with the Smagorinsky model. The method is verified with an experiment and RANS calculation of the buoyant wall jet issuing on a solid surface. The method then is used to simulate the dispersion and dilution of the effluent from a typical marine outfall installed on the seabed of shallow coastal water. The behavior of the plume in the vicinity of the outfall is simulated well reproducing the dilution process and the surface boil. The results indicate that they can be used to estimate the effects of the outfall discharge on the water quality and the temperature in the near field to help design and determine a desirable treatment plant operation method.

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Two cases of solitary motion experiment have been conducted over smooth beds by using solitary wave generation system facilitated by two types of rotating disk, the detail explanation about these rotating disks can be found in the former publication. In the present study, a deep analysis has been done to verify the sufficiency of tranquil period between two peaks of “solitary-wave-like” motion in turbulent flow regime and also to validate the reliability or sensitivity of ensemble averaging to 50 wave numbers produces by continuous measurement. The analysis results show that the minimum number of “periodical” or continuous wave measurement to attain reliable ensemble average is 45 wave numbers for case of turbulent solitary motion with Reynolds number (Re) = 7.34 x 105.

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Munk-Multhop’s method is usually used for estimation of pitching moment of fuselage of conventional aircraft but application of the same for hybrid lifting fuselage had not been earlier explored. CFD methods can also be applied for the said purpose but it is difficult to separate out the portion of the moment caused by the fuselage, since the wing and fuselage affect each other. In the present work, a hull disguised as hybrid lifting fuselage of a hybrid buoyant aircraft was taken as a test case. Slope of the pitching moment obtained from the Munk-Multhop’s method was further corrected to account for the effect of slenderness ratio. Good agreement of results was found after defining the camber profile of the hybrid lifting fuselage and applying the said correction. The location of the wing relative to the fuselage and lift curve slope of wings has a dominant role in estimation of pitching moment coefficient of the fuselage.

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In this paper a generic thermodynamic equilibrium model-based framework for biomass gasification processes has been developed. The designed framework contains a modelling for downdraft and fluidized bed gasifier. A biomass database has been developed as a supporting tools for this framework enabling this framework applicable to study a wide range of biomass gasification processes. Application of this framework has been highlighted based on two objectives. The first objective is to validate the thermodynamic equilibrium model for downdraft gasifier using wood and for fluidized bed gasifier using rice husk respectively. The predicted model shows a good agreement with literature data in terms of gas compositions produced indicating a reliable and valid model is achieved. Meanwhile the second objective of this study is to investigate the optimum parameters for downdraft and fluidized bed gasifiers using wood, rice husk, saw dust and empty fruit brunch. Based on this analysis, the optimum parameters obtained are at temperature 770°C with moisture content of 0.2 and steam biomass ratio 1.32, where the hydrogen gas produced from wood, rice husk, sawdust and empty fruit bunch in downdraft gasifier is 16.38%, 17.02%, 15.11% and 50.12 % respectively, while in the fluidized bed gasifier is 38.75%, 50.12%, 73.24% and 71.77% respectively. The result of the performance analysis shows that the fluidized bed gasifier is more efficient than downdraft gasifier in term of hydrogen gas production.

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Water-in-crude oil (W/O) emulsions are found in many industries such as cosmetic, pharmaceutical, and petroleum. The study was aimed to investigate the rheological properties and the stability mechanism of W/O emulsions at different water to oil ratios of (20-80 vol.%) and (40-60 vol.%). The emulsions were stabilized by a non-ionic surfactant (Span 83) at concentrations of 1.5-2.5 vol.%. The heavy and light crude oils were mixed at 50-50 vol.% and characterized in terms of physical and chemical properties. From the results, it was found that the emulsion with higher water volume fraction obtained more viscosity with larger droplet sizes which present low stability. As well as, the higher viscosity was obtained in emulsion with higher emulsifier concentration (2.5 vol.%). However, 20-80 % W/O emulsion and emulsions stabilized with 2.5 % Span 83 produced more stable emulsions as observed through the optical microscopy images. In order to determine the dynamic viscosity, different temperatures from (30 to 90 ºC) and spindle rotational speeds from (50 to 250 rpm) were used. Furthermore, all types of prepared emulsions were visually stable over a period of more than one week, where no water separation was observed during this period, besides; they exhibited a non- Newtonian shear thinning fluid behavior.

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Carbonaceous fiber produced via Hydrothermal Carbonization (HTC) process of Kenaf fiber was used as the filler for superabsorbent carbonaceous composite (SPC). The SPC were applied as water adsorbents in agriculture field to increase soil absorption and water holding capacity.These characteristic are very essential to experience the effect of dehydration and minimize the effect of drought stress in crops. This work aimed to synthesize the superabsorbent carbonaceous kenaf fibers at different amount of carbon filler. The SPC were synthesized by graft polymerization using carbonaceous fibers with sodium hydroxide (NaOH), acrylic acid (AA), N,N’-methylene bisacrylamide (MBA) as cross-linker and also ammonium persulfate (APS) as initiator. Tea bag method was used to measure the equilibrium swelling ratio in deionized water of the synthesized SPC. The structure and morphologies of the SPC were characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM). Overall results show that the water absorbency increased from 166.25 to 237.15 g water/g sample with the increasing of carbon filler from 0.1 to 0.5wt%. In conclusion, low cost superabsorbent material can help to retain nutrients by adding carbonaceous fiber content and absorb water in soil with various applications for plant growth and soil condition which will be useful especially in agriculture field.

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Sewage sludge ash (SSA) is a waste material obtained from the incineration of wastewater sludge. Hence, an investigation was carried out to study the potential use of SSA in cement based materials. The chemical and mineralogical characteristics of SSA in cement mortar are presented in this paper. Effect of incineration temperature and percentage of SSA as partial cement replacement in cement mortar were examined. The percentage of SSA considered in this study was 10% replacement of the mass of cement whereas the incineration temperatures investigated were at 600°C and 800°C. The tests conducted in this study consists of X-ray Diffraction (XRD), X-ray Fluorescence (XRF) and Field Emission Scanning Electronic Microscope (FESEM) as well as compressive strength test. Results show that a significant amount of SiO2, Al2O3 and CaO was traced after the incineration process. Mortar samples with 10% cement replacement of 800°C burnt SSA improves the compressive strength up to 1.14% and 5.06% at the ages of 28 and 90 days, respectively. The FESEM test results show that SSA samples burnt at 600°C exhibited needle-shaped particles whereas a smooth structure was found in SSA burnt at 800°C due to the pozzolanic reaction which filled the void and pores in the mortar. This bonding also provides additional strength to the mortar where the compressive strength has increased after 28 and 90 days.

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Murraya Koenigii leaves contain many useful chemical constituents. The leaves which known as daun kari in Malaysia is belong to family Rutaceace and can be found in Malaysia, India, Bangladesh, Nepal, Sri Lanka and Burma. The aim of this study is to characterize the components of essential oil of the leaves and finding its potential to be applied as insect repellent. The essential oil was extracted using steam distillation and hydro-distillation. The amount of leaves and water used were 200 gram and 2 mL. The time of extraction for both methods were between 3 to 9 hours. For every hour of extraction time, the yield between these two methods were compared. The results shows that the percentage yield for steam distillation in method is higher compared to conventional method which is hydro-distillation method. The highest yield obtained from 9 hours steam distillation is 0.25% (w/w) whereby 9 hours hydro-distillation method can only collected 0.09% (w/w) of yield. Components identification of the essential oil performed by GC-MS detected the presence of 30 different components, majorly hydrocarbons. The analysis reported the existence of a-pinene and Caryophyllene which are the active ingredients for insect repellent. Based on this study, the present of these two repellent activity compounds in the extracted essential oil proves its potential to be used as active ingredients in natural-based insect repellent. The repellency test towards Blattaria shows 100% repellency.

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Ferulic acid is covalently linked with variety of ester bond in plant cell wall make it challenging to be released naturally. Therefore, appropriate fermentation technique with co-culture could be an effective way to produce ferulic acid. The aims of this research were to develop the co-culture system and to evaluate their performance in releasing ferulic acid. Highest production of ferulic acid from banana stem waste as their sole carbon source was found in co-culture of Bacillus cereus CCM 2010, Bacillus pumilus SAFR-032 and Bacillus thuringiensis Bt407. The co-culture was successfully increased 2.6-fold production compared to single culture in 24 hours period of fermentation. Production of ferulic acid were being consistent each production simply by maintaining the quality of the co-culture. The result of this study suggests that synergistic work by co-culture represents a significant role in manufacturing of valuable product through fermentation of agricultural waste.

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Aluminium is totally recyclable with no downgrading of its qualities, but in the process of typical conventional aluminium recycling, there are quite a number of negative impacts. The recycling of aluminium and its alloys by direct recycling method is relatively simple, consumes small amount of energy, produce small amount of waste and does not have a harmful effect on the environment. This approach use hot press forging which eliminated two pre-process steps which typically introduce in conventional and semi-direct recycling. Hot press forging of aluminium 6xxx series is hot working process which means that the alloys should be heated around 460-520°C, slightly above the recrystallization temperature. After heating the material, 1 to 2 hours of soaking times are sufficient to redissolve the aluminium under the flow stress less than 47 MPa. Review on recycling aluminium chips using hot press forging show that there are good potential of strength and plasticity. This is proved that such recycling technique could be employed as an alternative method to replace the conventional aluminium recycling process.

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This paper discusses a finite element analysis of a flat plate subjected to normal constant loading (cylinder-on-flat configuration) with reciprocating sliding contact. The material properties follow a linear kinematic hardening plasticity model and the manipulated reciprocating tangential displacements are simulated for different sliding amplitudes, starting from 0.05 mm, 0.1 mm and 0.2 mm respectively. The predicted plastic deformation evolution on the contact region are reported for several parameters, i.e. equivalent plastic strain, tangential plastic strain, shear plastic strain tangential stress and shear stress distributions. The effect of applied sliding displacement amplitude on stress and strain distributions is also investigated. The simulation results show that the stress distributions for kinematic hardening model are almost similar pattern for all three sliding displacements. The plastic strain distribution is proportional to the reciprocating sliding displacement amount, higher sliding displacement resulting higher plastic strain distribution. The trend of the plastic strain distributions is increasing consistently when the sliding displacement varies from 0.05 mm, 0.1 mm and 0.2 mm. It is found that the strain effect depends on the sliding displacement amplitude.

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In the present study, an attempt was made to predict the extrusion speed and temperature during the hot extrusion of 6061 aluminium alloy chips by using Deform 3D simulation. The influence of extrusion process parameters, namely ram speed (Vr), preheat temperature (Tph), preheat time (tph) and extrusion die angle on the responses flow stress and heat distribution was investigated. One of the dies was a flat-face die, which represents a conventional extrusion die design for production of solid aluminium profiles. This study concentrated on improving the understanding of the behavior and the formation mechanism distribution with the aim of predicting the best on parameter process hot extrusion of 6061 aluminium alloy chip by using Deform 3D simulation without lubricant. Ram speed 2 mm/s at 500°C was affecting the amount of heat generated and also the amount of heat loss to the extrusion tooling and made insufficient on quality bonding. In the FEM code, the results of the simulations were compared and confirmed successfully by the experimental results.

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To design a mechanical systems, the designer should be proficient in the design of individual elements and components that embrace the system. There are few parametrs commonly needed to consider for its design, such as part dimensions, shape, material, load and nature of application. In this paper the design and effects analysis of static loading on motion interchanger unit of hybrid mobile robot is presented. The motion interchanger is a switchover module that helps the locomotion system transformability while robot moves on wheel or track mechanism. For the effective and reliable robot design, the model were then analyzed under static loading condition. The selected material aluminium alloys Al7075-T6 were subjected under different static load conditions i.e. 200N, 400N, 600N, 800N & 1kN for its mechanical behaviour analysis. The study concluded through the simulation results that the mobile robot with material aluminium alloy Al7075-T6 would failed with the increase of static loading.

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The aims of the research work described in this paper is to find out an alternative source of heat in carbonation process to make local briquettes using cheaper fuel by mean of heat generated from the combustion gases of coal gasification. The research was initiated from collecting raw materials which has a low calorific value. initially, coal was dried to make a maximum moisture content up to 12 % and form the coal at size of 10 cm. Further process were filling the vertical downdraft gasifier as much as 6 kg of coal, burned it with liquid petroleum gas (LPG) as igniter, turn on the blower with the maximum speed in order to find combustion process. After that, all coal in the surface of gasifier have been burned, attach the burner and then count the velocity of air that was produced by blower as parameters to obtain the optimal velocty in order to get the perfect combustion. The result showed that the coal gasification technology with vertical downdraft gasifier system is promising to be developed as a source of heat in the process of carbonation of local coal briquettes. Using 6 kg of coal gasification can produce temperature at furnace carbonation around 170oC as long as 60 mim with local kokas-briquettes that are carbonated at 10 kg.

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This research focuses on the effect of three different nose designs on glass fiber reinforced polyester composite laminates under different quasi-static speed loading. Laminated composite which act as target material is fabricated in orientation of unidirectional with 6 layers of plies by using vacuum bagging. 75 samples were tested under quasi-static test using three different impactors which is blunt, conical and hemispherical nosed impactors under loading speeds of 10, 20, 30, 40 and 50 mm/min. A further comparison was made with the maximum force required of each of the impactor. The fracture behavior of laminated composite caused by different inpactor was monitored under the scanning electron microscope to determine the type of failure occured after quasi-static test. The finding shows that conical nosed impactor required lowest force to penetrate the target material followed by hemispherical and blunt nosed impactor. In comparison with Conical impactor hemispherical nosed impactor and blunt nosed impactor shows 15% and 74% reduction respectively in term of effectiveness.. As the loading speed increased, the force needed for each impactor is increased. From the finding, loading speed of 30 mm/min shows the best speed for quasi-static to carry out. Furthermore, energy absorption that caused by three impactors show that conical nosed impactor produced smallest range of plastic zone where hemispherical nosed impactor and blunt nosed impactor create 1.8 % and 11.6 % respectively, higher range in plastic zone. Pull out of fibers and fibers breakage were observed on the sample after testing. The failure characteristic changed from ?ber pull-out to ?ber breakage. The nose surface area in contact with the target material produces high effect on the failure behavior of target material, the smaller the area, the higher the penetration resistance of target material.

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The depletion of fossil fuel combine with implications of exhaust emissions is regarded as one of the future challenges towards automotive researches. The used of alcohol fuel blends with conventional diesel fuel has attracted wide attention due to their liquid nature, high oxygen contents and high octane number. In this study the used of 10% butanol blends (Bu10) in a modern common rail diesel engine were investigated by means of their cyclic variations and peak in-cylinder pressure. The experimental test results showed that Bu10 endure inconsistency in term of the combustion stability as the calculated standard deviation (SD) of peak to peak in-cylinder pressure is greater than the diesel fuel at both BMEP = 1.2 Bar and BMEP = 3.5 Bar. Based on the statistical analysis Bu10 experience less than 2.17% of peak in-cylinder pressure at minimum, median and maximum conditions. For frequency distribution most of Bu10 fall in the range of 61-62 by 42 at BMEP = 1.2 bar, meanwhile at BMEP=3.5 bar 72-73 by 58.

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The depletion in natural gas and oil in shallow waters due to extensive extraction along with the increase in its demand has led engineers to develop the floating production platforms which can thrive well in the adverse conditions of deep waters. Floating production Storage and Offloading (FPSO) system has proven to be one of the most promising platforms in the development of offshore oil and gas resources that would be otherwise impossible or uneconomical to tap. In this study, an uncoupled dynamic analysis is performed using the Sesam HydroD software to study the response of FPSO under the action of unidirectional random waves in Malaysian waters in operating conditions in the Kikeh Field. The results can be referred for conceptual design of the FPSO system in Malaysian waters.

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With the current trend use of lighter structure and more power-intensive engines in automotive and aircraft manufacturing, vibrations are expected to increase due to its adverse effects on the vibratory behaviour. This could turn out to be a critical problem if the vibration not being controlled through a proper approach. Due to that reason, this paper aims to develop a small-scale and weightless vibration absorber made from natural fibres-based polymer epoxy composites. Two types of natural fibres were selected for reinforcement; sugarcane bagasse fibres and kenaf fibres at different fractions 5–20 wt%. In prior to vibration study, the tensile mechanical test was performed in order to determine the optimum fraction of the composites, as well as making comparisons of both composites reinforced by sugarcane bagasse fibres and kenaf fibres. It was found that the 20 wt% of sugarcane bagasse fibres composite achieves the highest Young's Modulus and tensile strength of 0.97 GPa and 21 MPa, respectively compared to epoxy reinforced kenaf fibres. Subsequently, the transmissibility test was carried out to determine the vibration absorption energy by using VCS software. Again, the result indicated that 20 wt% sugarcane bagasse/epoxy composite accomplishes the highest resonance frequencies at 22.9 Hz for 1 mm and 20.6 Hz for 1.5 mm. For the damping properties, it was found that sugarcane bagasse composites increase the damping ratio up to 8%. In the final stage of study, the small-scale vibration absorber was fabricated by using the optimum fraction of composite which determined from both previous testing. The vibration test was performed on a fixed-fixed ends beam and the results showed the resonance amplitude of the beam decreased significantly when it attached with vibration absorber. It concludes that adding more vibration absorbers attached on the beam produce better result in vibration reduction.

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This present paper addresses on designing the kit parts for variant engine model in new kitting area of sub-assembly line, one of the main processes in final assembly line. To date, a variant model of vehicles leading to parts variety that can deliver inefficiency of production in terms of cost and time. One of the major processes in vehicle assembly, that is sub-assembly line aims at producing a large number of finish line products encompasses variety of components that supports other main assembly process such as final assembly. The availability of parts needed at each workstation in the assembly line is critical for the production efficiency. Due to this fact, this paper aim to design a kit for two variants engine models in a reliable feeding system. This situation ensure the required parts available at line with high diversity of components and different physical features (i.e. weight, volume) to name a few in single complete different model. As such, the total operating cost and time consume in assembly production is rely on how efficient the system can response to a prompt target plan without neglecting the quality of the product. A design of kit for parts placing enables reliability of variant parts model in single line that will corresponds to mass customization of the production line. Overall, this paper offers a solution in terms of the availability of parts needed in rapid mass customization production of assembly line at one of the key player manufacturer plant in automotive industry. It is expected that the findings of this on-going study will provide production team with kits design to choose from in evaluating the assembly system performance which would lead to the production efficiency as well as minimize the associated costs.

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Recently, image analysis techniques in monitoring non-aqueous phase liquid (NAPL) migration have been gaining attention from researchers. Over the last two decades, photographic methods such as light reflection and light transmission methods have been shown to be applicable and effective tools for characterization and measuring NAPL migration. A review of recent studies published on light reflection and light transmission methods used in NAPL migration is summarized and presented in this paper. Besides discussion on the research efforts, recommendations for future research in using light reflection and light transmission methods are provided. This study concluded that, although having some limitations and drawbacks, photographic methods are still a promising and valuable tool for measuring NAPL migration.

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In this study, functionally graded natural fiber/epoxy (FGNF/epoxy) hollow cylinders are fabricated using the centrifugal casting method. The natural fiber (NF) used is banana trunk. Due to difference in density of NF and epoxy causes the NF particles in the epoxy liquid moves to the outside radius of the mold during casting. As a result, the hollow cylinders of FGNF/epoxy with different natural fiber content along the cylinder thickness are produced. NF is mixed with epoxy at three different fiber compositions which is at 2.5, 5 and 7.5 mass %. As the reference, the epoxy cylinder without fiber was fabricated. Three different speed rotating mold, i.e. 1145, 1187 and 1240 rpm are studied. In order to characterize the FGNF/epoxy cylinders fabricated, the hardness, density and compression test are carried out. Moreover, the microstructures of the FGNF/epoxy cylinders fabricated are observed using optical microscope. From the results, it is found that the NF particles can be graded from inner to outer surface of the FGNF/epoxy cylinders by centrifugal casting. The graded distribution in the FGNF/epoxy cylinders is significantly affected by the mold rotation speed and NF composition. Based on the result, the higher value of hardness, density and strength along the cylinder are located from the outer surface reduce gradually to the inner surface. It is because the NF composition of the outer was higher than that at the inner surface. In conclusion, it appears that FGNF/epoxy with a gradient in NF composition is superior to the homogeneous composite.

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In the last years, there is an increasing acknowledgment of our impact on the environment due to our lifestyle, while the need to adopt a more sustainable approach as to our consumption habits emerges as of particular significance. This trend regards industrial sectors affecting the consumption habits and, especially, electronic industry where the short life cycles and the rapidly developing technology have led to increased e-waste volumes, such as discarded electronic equipment. The majority of such elements result in landfills. However, their partial recyclability, due to their material composition (combination of different metals, such as copper, aluminium and steel, attached to, covered with or mixed with several types of plastics and ceramics) along with the unavoidable restrictions in landfills, has led to the development of retrieval techniques for their recycling and re-use, highlighting the significance of e-waste recycling, not only from a waste management aspect but also from a valuable materials' retrieval aspect. In this paper the method of hydrometallurgy is adopted to recycle metals from waste printed circuit board (PCB). An experimental leaching test was built up to recover precious and hazardous metals from the PCB. Experimental results showed that HCi can be used as metals-formation material to separate metal from PCB during the leaching process. Those results helped to find a way to recover metals and precious metals from PCB. It was revealed that the metal elements in e-waste can be dissolved using this method and further investigation to increase the dissolution rate is required to ensure that the method proposed is applicable in industry. However, dissolved concentration of Pb must be controlled to ensure that it follows the permissible amount set under environmental standard.

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The present paper investigated the effect of the lightweight dynamic vibration absorber (LDVA) to reduce vibration of thin walled structure. The free and forced vibration response of a rectangular thin plate were performed using finite element method. Subsequently, the effects of attached single and dual LDVA were analysed in depth by using Ansys workbench 14.5. Results demonstrated that single LDVA attached at the centre of the plate succesfully attenuate vibration over the frequency range of 0- 600 Hz. By contrast, attached with dual LDVA only suppresses the resonance of the first second and fourth modes but not for third and fifth modes of thin walled structure. It was found that by simply increasing the weight of mass does not improve the vibration absorption over the entire frequency range. The study conclude that attached single LDVA are better than dual LDVA for vibration absorption of thin walled structure over the entire frequency range.

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A solar powered evaporative cooling system of 0.6 m3 capacity was designed and constructed to increase the shelf life of stored vegetables. The evaporative cooler was tested and evaluated using tomato (Roma). The equipment operates on the principle of evaporative cooling and increasing the relative humidity (RH) in the preservation chamber. The storage system was made up of aluminum sheets of 1mm thick while a side of the system is made of jute pad which get moist by water flowing through a series of perforated pipe from the reservoir located at the top of the storage system. The water flows with the influence of gravity. The RH and weight loss of tomato was statistically analyzed using student T – test and the result revealed that there was significant difference in using the evaporative cooling system for storing tomatoes as compared to ambient condition. The average cooling efficiency was found to be 83%. The temperature in the system dropped drastically when compared to the ambient condition which ranges from 6 to 10°C and the relative humidity in the cooling chamber increased considerably to 85%. However, the testing of the evaporative cooling system shows that the tomatoes can be stored for an average of five (5) days with negligible changes in weight, color, firmness and rotting as compared to ambient condition which started rotting after three (3) days. Hence, it is on this note that farmers, house holders and tomatoes processing factories should adopt the use such evaporative cooling system for the storing of fresh tomatoes as this increases the shelf life of tomatoes.

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A finite strain constitutive model for orthotropic metals was developed within a consistent thermodynamic framework of irreversible process in this paper ro capture the deformation behaviour of commercial aluminum alloy. The important features of this formulation are the multiplicative decomposition of the deformation gradient and a new decomposition of deviatoric and spherical parts of Mandel stress tensor. The elastic free energy function and the yield function are defined within an invariant theory. The Hill’s yield criterion was adopted and the thermally micromechanical-based model, Mechanical Threshold Model (MTS) was used as a referential curve. The model complexity was further extended by coupling the formulation with the shock Equation of State (EOS). The proposed formulation was the implemented into the Lawrence Livermore National Laboratory-DYNA3D code and validated against the available experimental data of Taylor Cylinder Impact test of commercial aluminum alloy AA7010. The proposed formulation showed a good agreement with respect to the reference experimental data.

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Cellulose ester is a biomass-derived material and exhibits excellent heat resistance and high transparency, properties required for optical film application. Recently, attention has been paid to cellulose esters due to their potential application as a functional film. Some cellulose esters such as cellulose acetate propionate (CAP) show extraordinary dispersion of orientation birefringence, in which the birefringence increases with increasing wavelength, a property required as a retardation film. The similar behaviour is also observed for cellulose triacetate (CTA) plasticized with tricresyl phosphate (TCP). In this study, the mechanical properties of pure and plasticized CAP and CTA at room and high temperatures are investigated to relate with their birefringence property. At room temperature, CTA film shows a higher brittleness than CAP film. At 15 K above their respective Tg, pure CAP and CTA can be stretched to draw ratio of 5.0 and 2.0, respectively. However, the addition of TCP slightly decreases the stretchability in both CAP and CTA to draw ratio of 4.5 and 1.5, respectively. The stretchability of both pure and plasticized CAP and CTA is found to increase with the increase of stretching temperature, which is useful to increase the value of orientation birefringence as it increases with draw ratio. However, birefringence value becomes lower at higher temperature. Thus, to obtain an optimum value of orientation birefringence, a balance between the draw ratio and stretching temperature has to be considered.

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Construction of hydraulic control structures is generally aimed to control the velocity of water flow in open channels. Controlled velocity water flow in open channels very important to reduce the hydrodynamic forces in the flow to be able to erode the banks of the canal and structure. This study focuses on changes of the flow profile and the specific energy that occurs in an open channel structure as a result of the construction of cylindrical hydraulic control structures and to obtain the effectiveness of cylindrical structure. A cylindrical structure with a diameter of 0.3 meters constructed in the middle of an open channel structure measuring 10 meters long and 0.3 meters wide. The effectiveness of the cylindrical structure derived from the results of two different conditions studied. Case 1, the opening in the surface of the cylindrical structure at a distance of 50 mm from the base of the structure at the upstream of the channel, while in the case 2 openings are positioned at a distance of 50 mm from the surface of the cylindrical structure at upstream of the open channel. As the consequence, the higher the opening on cylindrical structure at upstream channel which in Case 2 more effective in controlling the flow in open channel. This is because the structure able to withstand greater upstream flow of up to 0.004m3/s compared to Case 1 were only able to withstand until 0.002m3/s. In addition, Case 2 is able to reduce the specific energy flow in the downstream channel by 21% and sub critical transition flow occurred at downstream. This structure also able to withstand water without causing flooding the upstream channel until 14.42s. Based on the overall results of the laboratory testing, the structure capable to control the flow in open channels and also can reduce the flow of energy that occurs in the downstream.

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In the absence of analytical theory, empirical equation is useful in estimating the ultimate load carrying capacity of structural component. Empirical approach means the collection of data on which to base a theory or derive a conclusion in science. It is part of the scientific method. The empirical method is often contrasts with the precision of the experimental method where data are derived from an experiment. This paper review the development of empirical equation from solid reforced panel to sandwich panel. The previous developed empirical equations are be able to predict an adequate ultimate strength of PLFP panel under axial loading due to the safety factor reduction. Series of experiment and Finite Element ANALYSIS (FEA) were carried out to produce sufficient data to analyze the previous developed empirical equation to predict the ultimate load carrying capacity. From findings, a new empirical equation is in need to predict the ultimate axial load of sandwich panel in order to get accurate prediction.

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Empirical equations to describe flow duration curve (FDC) are mostly in the form of exponential, logarithmic, power or even polynomial functions but none of these fit the dataset of the study site of this research. This paper proposed two new empirical functions, modified from soil water retention equations. The efficiency and prediction accuracy of our new empirical equations were evaluated against each mentioned common function at the study site. Polynomial function was discarded as it failed to fit the dataset. Power function over-predicted nearly every quantile and induced un-acceptable huge difference especially at high flow end of the FDC. Logarithmic was the only function that yields negative predicted low flow and under predicted peak flow by 85%. On the other hand, exponential function almost under predicted peak flows by 100%. New empirical equations have highest Nash-Sutcliffe efficiency with lowest overall RMSE, quantile cumulative RMSE at high flow range and percentage error at the highest peak flow points. A parsimonious form of the new empirical equation was also presented and discussed in this paper.

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There many potential ways to enhance the performance of bituminous mixture used in the surfacing course of road pavements. Due to inadequacy from previous research on Batu Pahat soft clay (BPSC) application as an additive in hot mix asphalt (HMA) mixture, BPSC was used as an additive and introduced in powder form in this present study. The purpose of this research is to evaluate and investigate the effects of BPSC particles on the performance of the HMA mixture. The experimental work for this survey included the use of five percentages of BPSC (0%, 2%, 4%, 6%, and 8%) in reference to the weight of bitumen; a design for the HMA was executed using the Superpave method for each additive ratio, and the optimum bitumen content for each percentage was used. In additional, with respect to assessing an impact for BPSC particles in the asphalt mixture, moisture susceptibility, resilient modulus, and dynamic creep tests were conducted. Through blending steps, the binder was kept at 160 °C, and the shear rate mixer was used for approximately 1 h at 3000 rpm. The results demonstrated that dynamic creep prepared with BPSC modified bitumen had a better resistance to deformation than the controlled mixture. In addition, the BPSC particle reduced the susceptibility to moisture damage and increased the strength of asphalt mixes. BPSC particles likewise improved the durability and rutting resistance of the resilient modulus. The increasing BPSC to 4% appears to hold the greatest potential for beneficial modification of the binder. This research proves that BPSC can improve properties such as, resilient modulus and moisture sensitivity and result in superior performance compared with unmodified bitumen under dynamic creep.

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The trend of Standardised Precipitation Index (SPI) was investigated for more than 100 years of data using non-parametric trend technique Mann Kendall (MK) to detect wet (increasing) and dry (decreasing) periods across Victoria, Australia. Preliminary trend analysis was carried out for five different stations out of the 70 stations selected for this study. Out of five stations, two stations showed significant decreasing, indicating an increase in magnitude of dry periods. While the other two stations exhibited significant increasing trends. The analysis was repeated using recent data from approximately half the data set between 1949 and 2011. Contrasting results from the original full data set analysis were revealed. Based on the conclusions drawn from the preliminary analysis, the trend analysis was applied using the MK test for the remaining 65 stations for full set of data. Overall, 29 stations exhibited a significant downward trend. These regions have experienced frequent drought events and evidenced by the presence of a negative trend in the SPI series obtained from the present study. On the other hand, 21 stations showed a significantly upward trend, indicating a shift towards wetter conditions. No significant trend was identified for the remaining 20 stations. In addition, this paper analysed the spatial pattern of the historical droughts using SPI. Conclusions drawn from this paper, point to the importance of selecting the time series data length in identifying trends. Due to the climate variability, trend testing results might be biased and strongly dependent on the data period selected. Therefore, the use of full data set available would be required in order to improve understanding on change or before to undertake any further studies.

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In this paper, attempts are made to use combination of numerical techniques to simulate fluid flow over a flat plate. The objective was not to investigate the physical phenomenon of flow in detail but to study numerical method as well as modeling aspects, which influence the quality of solutions. The incompressible Navier Stokes equations with large eddy simulation (LES) turbulence model were numerically solved to estimate velocity profile over surface of flat body exposed to current. The results are obtained by solving the incompressible form of the mass and momentum conservation equations using finite volume method. The near wall model and the subgrid scale (SGS) model plays an important role on modeling. Accordingly, proper boundary layer condition based on logarithmic velocity profile was imposed to capture turbulent velocity near to the wall. Several techniques such as local time steeping, residual smoothing and unstructured multigrid mesh were used to increase convergence acceleration. Results from large eddy simulation with Smagorinsky subgrid scale model are presented in two different types of flow such as laminar ant turbulent flow. All computed results are compared with Blasius solution or experimental data represented in literature. The results show good agreement with the aforementioned experimental and computational data. Imposing logarithmic law for velocity profile normal to the wall provide more accurate velocity profile in general especially for relatively coarse mesh.

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To sustain a greener image of the palm oil industry, the producing countries have been placing remarkable efforts to promote palm oil as an environmental friendly product. This paper aims to report a study regarding the wastes generated in local palm oil mills. Study was conducted to seven palm oil mills of different capacity, years of operation commencement, and management background. Attention is given to milling wastes as they represent a wider potential for beneficial reuse and probably leads to monetary returns, large quantity, and more environmental hazardous. Milling wastes included lignocellulosic palm biomasses namely the empty fruit bunches (EFB), oil palm shells (OPS), mesocarp fibres, palm oil mill effluent (POME), and palm oil mill sludge (POMS), as well as the solid wastes generated as a result from further processing of these biomasses into the palm oil fuel ashes (POFA) and palm oil clinkers (POC). An agro-industrial waste profile for palm oil mills was computed based on the thirteen years operation and production data. Management approaches of these palm oil mills on the by-products were also summarised. The information will be attention-grabbing for estimation and later prediction of the oil palm wastes accessibility, hence offer a statistic for future references.

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The increasing demand for natural sand supply by concrete industry and rising quantity of palm oil fuel ash, an environmentally polluting solid waste disposed by Malaysian palm oil industry has led to the innovation of aerated concrete containing palm oil fuel ash as partial sand replacement material. This lightweight concrete exhibits improvement in the compressive strength with the incorporation of 30% palm oil fuel ash. However, the long term experimental result of the strength and durability performance of this modified concrete is unavailable. This paper reports the one year result on strength performance of aerated concrete containing palm oil fuel ash when subjected to different curing method and behavior of this material upon exposure to long term sulphate attack. Comparisons are made between behavior of plain aerated concrete mix as control specimen and another mix, aerated concrete with 30% palm oil fuel ash as partial sand replacement. Compressive strength performance of the specimens were observed by placing it in two types of curing regime, water curing and air curing. Durability of the mixes were assessed by exposing the specimens in Sodium sulphate environment. Findings indicate that water curing promotes better pozzolanic reaction in aerated concrete containing palm oil fuel ash, that leads to formation of larger amount of C-S-H gel resulting it to be stronger than control specimen. Integration of palm oil fuel ash consumes calcium hydroxide which is vulnerable to sulphate attack and produces secondary C-S-H gel making the concrete more compact thus enhancing its durability against sulphate attack.

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In recent years, there has been increasing awareness of the importance of using information technology in improving “green building” performance in terms of design, construction, and operation. Assessment tools help industry stakeholders evaluate the performance of green buildings. Building information modeling (BIM) enables architecture, engineering, and construction managers to evaluate the performance of green buildings during preconstruction. BIM-based sustainable analysis extracts the data from a building model, which supports the assessment for green building certification. This paper explores the use of BIM with other assessment tools, such as Leadership in Energy and Environmental Design, BEAM Plus and Green Star. The study also examines the potential use of BIM in green building rating systems and the possibility of achieving credit via BIM tools and analysis software. In a case study of a construction project, using green building assessment tools integrated with BIM has led to an improved green building and facilitated the performance assessment of this building during the certification process.

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Batch tests were employed to estimate the optimal conditions for improving the settleability of activated sludge through aggregation under magnetic field. A four – factor central composite design (CCD) was employed to find out the interaction effects of the variables while response surface methodology (RSM) was utilized for process optimization. Four independent variables, viz. magnetic field (15.0 – 88.0 mT), exposure time (0.5 – 48.0 hrs), biomass concentration (2000 – 4000 mg l-1 ) and mixing intensity (200 – 400 rpm) was built to predict the responses. Analysis of variance (ANOVA) was used to evaluate the significance of the independent variables and their interactions. At the optimum conditions of 88.0 mT magnetic field, 16.5 hrs of exposure time, 2800 mg l-1 of biomass concentration and 300 rpm of mixing intensity, the aggregation achieved its maximum value by 99.0%. The element analysis showed that the applied magnetic field is potential to enhance the settling property of the activated sludge by improving its aggregation.

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The effectiveness of water hyacinth (EichhorniaCrassipes) in the remediation of municipal wastewater and production of bioethanol was compared with water lettuce (Pistia Stratiotes) and water spinach (Ipomoea Aquatica). Preliminary test using hydroponic system was conducted in order to measure the parameters required at the laboratory scale continuous experimental rig configuration (hydraulic retention time and flowrate). The experiment using the experimental rig was conducted for 18 d for each of the aquatic plant. Water lettuce showed a better removal performance compared with water hyacinth and water spinach. Water lettuce was able to remove 92% of nitrogen and 87% of phosphorus. Besides, water lettuce also showed higher BOD removal of 98.3% followed by water hyacinth 93.9% and then water spinach 89.6%. For COD removal performance, water lettuce treated COD up to 98% followed by water hyacinth 94.2% and water spinach 89.9%. The biomass harvested from water hyacinth, water lettuce and water spinach was 772 ± 37 g/kg, 794 ± 75 g/kg and 702 ± 69 g/kg, respectively. The DNS test was conducted to measure the reducing sugar from the plant biomass. The concentration of sugar produced by water hyacinth was 21.2 ± 2.7 g/L-m2, while water lettuce was 23.5 ± 3.8 g/L which is higher than water hyacinth’s sugar production. Water spinach produced the lowest sugar concentration with only 15.5 ± 3.3 g/L. The production of biofuel was estimated based on known theories. Water lettuce produced 0.13 ± 0.01 g/g bioethanol while water hyacinth produced 0.12 ± 0.01 g/g of bioethanol. Due to the low concentration of sugar, water spinach managed to produce only 0.10 ± 0.02 g/g bioethanol. Water lettuce showed better performance in comparison with water hyacinth in the remediation of wastewater and subsequent production of biofuel.

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Kaolin soil represents the soft clay soil with a depleted bearing capacity and an elevated compressibility level. Thus, in order to hold up civil structures, the bearing capacity of kaolin soil needs to be raised. Several soil improvement procedures are currently available. These include soil replacement, preloading, corduroy and chemical stabilization. However, as these procedures are harmful to the environment, efforts to achieve soil stabilization ought to make use of materials that are environmentally friendly. The utilization of industrial waste that does not have a negative impact on the environment would represent a significant step forward in this area. Among the most frequently employed procedures to achieve soil stabilization is the utilization of a binder such as lime. This study puts forward an array of laboratory investigations to assess the influence of lime on the compressibility and swelling traits of soil. According to the findings, the liquid limit and plasticity index of soil is reduced with the introduction of lime. Pozzolanic reactions transpire due to the siliceous and aluminous nature of the material which has a negligible cementation value and is made up of large particles. This circumstance culminates in a reduction of the liquid limit. With a 9% application of lime, an elevation in the liquid limit was observed (a decrease in other reaction materials). This is attributed to the excessive presence of lime. The optimal water content rose from 20% to 23% with a 5% application of lime. The stabilizer content (lime) reduces the maximum dry density from 1.63 to 1.585 g/cm3. Lime content enhances the compressibility of soft clay by lowering the coefficient of volume compressibility (mv) reduces with increasing stabilizer content and the optimum percent for lime. This is a result of the reaction between lime and soil.

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Effect of solvent debinding variables for extracting Fats, Oils and Grease (FOG) derivatives from different binder formulation feedstock were studied. The green compact with different binder formulation will be tested with two different organic solvents which are n-hexane and n-heptane at fixed solvent to weight ratio of 14:1 with temperature of 40, 50 and 60°C for 10 hours. Effect of extraction temperature, solvents and time on green compact with different binder formulation will be monitored base on diffusion coefficient and weight loss. It is found that types of solvent, temperature and time has influence on extracting FOG derivatives from green compact with different binder formulation.

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The development of Artificial Intelligent (AI) technology system can be a wide scope; for an instant, there are rule-based expert system, frame-based expert system, fuzzy logic, neural network, genetic algorithm, etc. The remarkable achievement applications of AI has been reported in different disciplines including field of medicals, militaries, chemistry, engineering, manufacturing, management, and others. Its’ discoveries and contributions through of AI study since the early 1970s were be significant step to enhance better performance of human work activities and probably replaced by these technologies. Today, there a lot of intelligent machine is available in everywhere such as airport gate scanner, movie theater counter ticket, vending machine, ATM machine, washing machine, etc. Expert system has been used widely in many areas and industries. This paper is described the current research and development of expert system.

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In railway vehicle technology, there are continuously increasing requirements regarding riding comfort, running safety, and speed of railway vehicles. These requirements are opposed by the fact that the condition of the tracks is getting worse and maintenance is becoming expensive. In view of this conflict, conventional suspension concepts are unable to accommodate those needs. This paper investigates the performance of semi-active control of lateral suspension system namely fuzzy body-based skyhook and fuzzy bogie-based skyhook for the purpose of attenuating the effects of track irregularities to the body lateral displacement, body roll angle and unwanted yaw responses of railway vehicle. In fuzzy bogie-based skyhook, a virtual damper is attached between bogie and sky to damp out unwanted vibratory motion of the bogie and to prevent the motion to be transmitted to the body. For fuzzy body-based skyhook, the virtual damper is attached between the body and the sky. The controller is optimized on 17-DOF railway vehicle dynamics model and shown 35 % better dynamics performance than its counterparts.

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High performance acoustic material is an attractive solution to a sound pollution. Nowadays, the used of synthetic fiber as a common acoustical panel has been detected hazardous to human health. There are several types of natural fiber materials, which have lower environmental impact than the synthetic materials and show better sound absorbing and sound insulation performances. Therefore researchers have become interested to find sustainable materials to be an alternative sound absorber material. This paper investigated the potential of oil palm Mesocarp fiber as fibrous acoustic material. The binder is constructed at prescribed percentages of polyurethane (PU). The measurement of sound absorption coefficient (SAC) was done by using the impedance tube method. The samples were also tested for physical properties which is the density and porosity. The result indicated that oil palm Mesocarp fiber is capable to be good sound absorption panel.

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Natural fibres are significantly used as reinforcements for the manufacture of low-costing and lightweight polymer composites; other advantages include innoxiously to human, easily obtain, and have a higher capacity of biodegradability. Therefore, researchers divert their attentions to find sustainable and eco-friendly materials such as natural fibres to be an alternative sound absorber. This paper discusses the use of natural fibre from the Kenaf fibre (Hibiscus Cannabinus), that eligible as sound absorber. This selected natural fibre is famous among the South East Asia countries and has a wide plantation. Sound absorption properties of this natural fibre have been investigated. Kenaf fibres are treated with alkaline treatment 2% individually to remove the unwanted dirt’s and bind with various percentages, 40%, 30%, 20% and 0% of natural rubber (latex). The thickness of each sample is kept constant at 50mm only. To obtain the sound absorption, the Kenaf fibre samples was measured using impedance tube. The measured values from impedance tube were compared with the empirical model Delany- Bazley in order to investigate sound absorption`s prediction result. In addition, bulk density, porosity and flow resistivity were also been examined. The result shows that Kenaf reach the maximum absorption coefficient value towards low frequency with fibre samples bind with natural rubber whereas fibres without the binder reach at high frequency range of 4000 Hz and above. In this preliminary study of the natural fibre i.e Kenaf fibre, it is shows that the fibre is a promising light and environment-friendly sound absorption material.

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The optimization of process parameters in family injection mold using moldflow simulation software was studied. Type of runner employed was linear runner layout system. The simulation matrix was planned using Taguchi method and the data were analyzed using Minitab. The family mold that consists of plastic parts such as tensile specimen, impact specimen, flexural specimen and hardness specimen were designed using CATIA. Then, designed plastic parts in CATIA software were imported into Moldflow software to transform the plastic specimen parts from solid form to mesh form. Feeding system such as sprue, runner and gate including water cooling system was designed inside the mold. Determination of the type of injection molding machine and the type of plastic material in the settings was taking under cool + fill + pack + warp analysis. It was found that the most influential parameters is melt temperature. Based on ANOVA result, all the three responses such as deflection, volumetric shrinkage and residual stress have significantly affected by melt temperature. Melt temperature is an important parameter to determine the deflection, shrinkage and residual stress that can lead to warpage of molded parts. High melt temperature value resulting in lowest value of deflection and in-cavity residual stress. Therefore, by using moldflow simulation software, it can helps manufacturers to predict and prevent any potential manufacturing defects as well as reducing cost and waste of material.

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Recently, researchers and industries have shown an increased interest in, natural fibres due to their advantages compared to synthetic fibres as it is environment friendly and low cost engineering materials. Low velocity impact response of fibre metal laminate (FML) based on short oil palm empty fruit bunch fibres according to weight percentage of 0%, 10%, 20%, 30%, 50% and 60% has been investigated. The specimens were prepared and tested using impact pendulum tester according to ASTM E-23 standard. The impact resistances of the various laminates were benchmarked with monolithic aluminium. Flat wise impact energy is almost equivalent with monolithic aluminium. This work shows that this type of FML can be used as a substitute to aluminium panels.

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Eco-products are products that were created as a step to overcome an environmental problem which is getting serious nowadays. However, there is no standard procedure or guideline for designers to consider an environmental aspect in the design stage. In this study, Environmentally Conscious Quality Function Deployment (ECQFD) approach has been proposed to be integrated in conceptual design activities, so that an improvement in terms of environmental aspects can be considered for a new design of an important product component. ECQFD methodology which consists of four phases is applied before new alternative concepts are generated. In the conceptual design activities, morphological chart is used to generate several possible concepts, then the selected concept is evaluated using weighted decision matrix based on criteria in the phase III of ECQFD. Thus, there is no need to redesign all components of a product if the most critical part can be identified at the early conceptual design stage. An example of a portable vacuum cleaner is used to illustrate the proposed approach. This approach provides a new and much more meaningful basis for developing eco-products in the design platform for designers.

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This paper investigates the effect of cutting parameters on the surface topography of AISI 316L stainless steel with tungsten carbide tool by using response surface methodology (RSM). Feed rates ranges from 0.10 mm/rev to 0.14 mm/rev while the cutting speeds ranges from 80 m/min to 120 m/min were used. Scanning electron microscope (SEM) and Mitutoyo surface tester were used to study in detail the surface topography of AISI 316L stainless steel. A mathematical relationship was built between cutting parameters and surface roughness. From the results it was found that feed rate was the main factor affecting the surface roughness while cutting speed have negligible effect on the surface roughness of the end-milled AISI 316L stainless steel samples. From analysis of variance it was found that the percentage contribution of feed rate was 10.38 % and cutting speed as 2.1 %.

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Electrical Discharge Machining (EDM) is a process used to remove or cut a material into desired shape through the action of spark discharge between the tool and work piece. The objective of this paper is to optimize the independent variables to achieve better accuracy in EDM small hole drilling by using Taguchi method. The L9 orthogonal array is employed to study the performance characteristics in drilling operations of mild steel (AS3679) as workpiece by using 1 mm copper (Cu) pipe electrode. Three drilling parameters namely, pulse off time, peak current and servo standard voltage are considered to optimize drilling hole diameter. The result concluded that use of greater pulse off time, greater peak current and medium servo standard voltage give the better hole diameter for the specific test range. Further study in this topic could consider different factor such as pulse on time, material removal rate (MRR) and coolants to investigate how these factors would affect hole diameter.

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Malaysian manufacturing sector has played an important role to boost up the economy at the domestic market. Today, the Malaysian manufacturing sector has facing the challenges that the manufacturing industry need to stay competitive to compete at the global market. Manufacturing cost of the company will directly affect on the company profit as well as product cost. Manufacturing cost may includes material cost, labor cost and overhead. Various type of techniques and methods have been used to lower the manufacturing cost. With the advancement of computer, computer software has been used to solve the manufacturing sector problem. In this research, expert system has been proposed to develop a diagnosis system to solve the problem of design of assemble. The effective assembly design of a product will able to reduce the total assembly time as well as reduce the manufacturing cost. An architecture framework of the developed Design for Assemble Expert system (DAEx) is described. The DFA expert system is developed using expert system shell to support the vehicle seat manufacturing process. Tha main aim is to reduce the assembly time and cost of vehicle seat manufacturing process.

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This paper reports an industrial application of framework based on axiomatic design (AD) principles to facilitate sustainable product development. A pedestal fan is used as the main subject of study and the case study was carried out in a household appliance company involving cross-functional collaboration between designer, procurement manager and manufacturing engineer to increase recovery profit of the product, while ensuring the sustainability of the supply chain and manufacturing at the same time. Results show that axiomatic design principles are able to guide designer/engineer in selecting functional embodiment that facilitates product recovery and fuzzy axiomatic design approach can be effective when dealing with problems concerning green supplier selection and optimization of manufacturing solution. Hence, this framework can be employed to provide guideline for companies in designing and developing sustainable products that are less harmful to environment in the subsequent lifecycle stages.

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Experimental works were conducted to investigate the effect of copper-oxide (CuO) nanoparticles volume concentration and the operating temperatures on the rate of nanofluids heat transfer in a compact heat exchanger. 40 nm CuO nanoparticles was mixed with demineralized water at 2% and 6% volume concentrations. Sodium Lauryl Sulphate (SLS) powder was added to enhance the mixing process and stabilize the dispersion of the nanofluids. A custom-made closed loop test rig were designed, fabricated and tested for these experiments. The test rig was set-up to represent the actual ap-plication of the nanofluids in cooling of a compact heat exchanger. Experimental runs were conducted at varying operating temperatures which include the runs for water, CuO-water at 40oC, 50oC and 60oC. The results indicate that by adding small amount of CuO nanoparticles into water as the base fluid, the rate of heat transfer and convection heat transfer coefficient would increases by at least 17.3% and 40% respectively. It was also discovered that CuO nanofluids with 2% volume loading produces greater increase in rate of heat transfer. Among the three operating temperatures selected for study, 40oC gives the best performance in heat transfer and the convection heat transfer coefficient. The results of the current work generally indicate that nanofluids have the potential to enhance the heat transfer of a compact heat exchanger if properly designed.

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In this paper the effects of honeycomb core filled with wood sawdust on their buckling mode and mechanical properties such as energy absorption are studied experimentally. Empty honeycomb core has limitation in energy absorption and filled it with other material can enhance the value of the energy. Wood sawdust is selected as the filler due to it is natural fiber and no chemical substance involve that can effect the healthy of the environment. Aluminium honeycomb core 3003 series and two types of wood sawdust, merbau and kenaf sawdust are subjected to quasi static axial compression loading. The results show the honeycomb filled with kenaf sawdust has higher energy absorption compared to empty honeycomb and honeycomb filled with merbau sawdust. But, for Specific Energy Absorb (SEA), the empty honeycomb core has higher value compared with the honeycomb with the filler due to the weight of empty honeycomb core is lower compared to other specimens.

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This study was carried out to study the effects of using nanofluids as abrasive machining coolants. The objective of this study is to investigate the performance of grinding of ductile iron based on response surface method and to develop optimization model for grinding parameters using artificial neural network technique. The abrasive machining process selected was surface grinding and it was carried out two different coolants which are conventional coolant and titanium dioxide nanocoolant. The selected inputs variables are table speed, depth of cut and type of grinding pattern which are single pass and multiple pass. The selected output parameters are temperature rise, surface roughness and material removal rate. The ANOVA test has been carried out to check the adequacy of the developed mathematical model. The second order mathematical model for MRR, surface roughness and temperature rise are developed based on response surface method. The artificial neural network model has been developed and analysis the performance parameters of grinding processes using two different types of coolant including the conventional as well as TiO2 nanocoolant. The obtained results shows that nanofluids as grinding coolants produces the better surface finish, good value of material removal rate and acts effectively on minimizing grinding temperature. The developed ANN model can be used as a basis of grinding processes.

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In this paper, we analysed convective boundary layer stagnation point flow of nanofluid influencing by suction and magnetic field over a porous shrinking surface is investigated numerically and simulated with Maple 18 Software. Thermophoresis and Brownian motion effects are included in the nanofluid model. Governing nonlinear boundary layer equations for momentum, energy and continuity equations are transformed into a system of nonlinear ordinary coupled differential equations by using similarity transformations. The effects of physical parameters on nanofluid (Liquid and Gaseous) are analysed. It is found that for a certain range of injection process, solutions exists for velocity flow, temperature flow and volume concentration. It tends to provide solutions for skin friction, rate of heat and rate of mass transfer of nanofluids (Liquid and Gaseous).

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The performance of natural coagulant made from tapioca starch (TS) on real partially stabilized leachate from Matang landfill was investigated. The percentage removals of suspended solid (SS), colour, chemical oxygen demand (COD) and ammonia under the influence of pH and dose by using coagulation-flocculation were recorded. The results revealed that the optimum values of pH and dose were 4 and 2.5 g/L Fe, respectively. At the optimum condition, 12%, 54.7% and 13.2% of SS, colour, and ammonia removals were achieved using TS. TS as a coagulant was able to remove SS, colour and ammonia from partially stabilized leachate. However, the removals obtained using TS were not as good as those obtained using the chemical coagulant.

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Obviously river water purification procesess are considered as a new approach and their implementation and applicatication are at fundamental basis but there are still current treatment technologies being researched and the outcomes maybe available in a while. This review paper present the various methods for urban river water purification including both conventional methods and new emerging technologies.The review also includes many relevant researches carried out at the laboratory and pilot scales. In river water purification process, biological-advanced technologies and other physicochemical methods are gaining much attention. While previously most treatment of river water have been carried out in conventional direct and bypass treatment, in recent years, here are many emerging technologies can be adapted for river water purification. Until recently, multivariable resources have not been available for researchers to have a rich supplementary data to synthesize and digest since river purification project is new and still in its beginning phase in developing countries. There are still current treatment technologies being researched and the outcomes maybe available in a while. However, the research concluded so far are compiled herein and reported for the first time to acquire a better perspective and insight on the subject with a view of meeting the news approach. Afterward, the most feasible technology could be the combination of advanced biological process (bioreactor systems) including Moving Bed Biofilm Reactor (MBBR) and Integrated Fixed Activated Sludge (IFAS) system, followed by solid separation prior to discharge.

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The courtyard is one of the traditional architectural forms that contributed in determining climatic environment, physical and psychological in the courtyard house. This paper focus on the history of courtyard and it is privacy measure in variant civilizations. Variants courtyard studies were investigated, beside the courtyard history, evolution, form and elements were recorded in terms of it is physical features and benefits. The result revealed that the courtyard around the world has a similar form, but the attributes are varied depending on the region climatic characteristic. The paper concludes with an outline of means to optimize a courtyard microclimate performance.

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Thorough understanding of the rainfall-runoff processes that influence watershed hydrological response is important and can be incorporated into the planning and management of water resources. This study assessed rainfall-runoff models through inferential statistics and benchmarked their runoff predictive accuracies against a proposed new runoff model. Linear regression model has been in use to model urban rainfall-runoff. However, the model was found to be statistically in-significant in this study. Hydrological implications from the regression model became in-consistent and obsolete. The 1954 simplified SCS runoff model was also statistical in-significant under two Null hypotheses rejection and paved way for the regional model calibration study. A new rainfall-runoff model was developed with calibration according to regional hydrological conditions. It out-performed simplified SCS runoff model and reduced RSS by 54%.

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Nowadays, practicing ‘industrial ecology’ for sustainable industrial development is a common practice in the engineering field. This practice promotes recycling by-product waste of one industry by substituting/replacing them for the virgin raw material of another industry, thereby reducing the environmental impact of both. One of those by-product wastes is bottom ash, which produced from coal-fired power plant that faces an increasing production up to hundred and thousand tones over the continents. Previously, a significant amount of research has been conducted in order to explore the potential use of bottom ash in the production of concrete and mortar. Most of the research focused on its potential use as fine aggregate replacing natural sand, and exploring its beneficial properties in enhancing the properties of concrete and mortar. This present paper reviews the literature related to the properties of fresh and hardened concrete incorporating bottom ash as a partial or total replacement to fine aggregate. Comprehensive review on physical, chemical and mechanical properties of bottom ash are presented. The effects of bottom ash on setting time, bleeding and segregation, workability, strength and durability of fresh and hardened concrete are also presented. An effective utilization of bottom ash in the construction industry may help in promoting ‘green’ culture and sustainable development.

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Construction joints are stopping places in the process of placing concrete, and construction joints are required because in most structures it is feasible to place concrete in one casting work. The amount of concrete that can be placed at one time is depend on the batching capacity and capabilities to construct formwork. A good construction joint should provide adequate flexural and shear continuity through the interface. In this study, the effect of type of construction joints on the performance of concrete structural elements is experimentally investigated. Six slab samples with dimensions of 700×400×150 mm were tested. The variables investigated are the type construction joints. All sample were tested using 100 kN computer controlled versatile electronic testing machine named as Magnus Frame. The sample was positioned in the machine so that the deflection at middle of sample measured at each load step. The results of the experimental program indicated controlled sample have the maximum applied load, deflection, stiffness and energy absorption. Sample incline joint named as joint sample 1 have the higher applied load, deflection and energy absorption compare to other joint sample, but joint sample 2 using Hy-Rib Mesh to form concrete joint have the higher stiffness compare to other joint sample. The value of joint sample 1 maximum load is 25.93kN, deflection were 0.68mm and energy absorption 8.261kN-mm, joint sample 2 have 47.36kN/mm stiffness compare to joint sample 2 which only have 34.58kN/mm. It was found that the Hy-Rib Mesh construction joint is the best joint as it have the maximum stiffness, higher stiffness of concrete have a higher characteristic of rigidity.

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These research had been develop in Paya Terubung, Penang, Malaysia. The objective of the study are to determine and classify potential area for landslide, produce map for potential area and build a user interface.The research aims is to monitor landslide using Geographical Information System (GIS). There are eight factors that contribute to landslide such as rainfall, river flow, soil type, slope, underground water, land use, erosion and mineral. A rating system with marks is given for each factor. The methodology of the study begin from data collection, transferring and processing, developing database, spatial analysis and finally result and discussion. The verification method is perform by comparison of existing landslide. The validation result show satisfactory between the susceptibility map and existing landslide location. Landslide Information System has been developing for user to access into the system. With this system, it will increase monitoring process and safety that involve landslide.

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Unexpected slope failure has the potential to the most costly form of failure as it leads to safety issues (loss of life) and sometime required time consuming remediation. A work over survey of on TNB substation at Kg Padang, Kuantan revealed a significant movement and failure of a slope within vicinity of excavation works. Ground investigation was conducted to establish information within underlying strata consists of GRAVEL and clayey SILT with traces of sandy which dominantly from residual soil. Laboratory testing and soil investigation are gather as an input parameter to propose a slope and analysis for stabilization. The analysis of slope stabilization reduced the hazard of further work involving cutting and trimming on mining area. Sensitivity study for angle of slope is to address the most effective and suitable for maximize extracting bauxite ore. Reducing slope gradient with improved site drainage to ensured safety for TNB substation was implementing as a remedial works from this study.

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Malaysia has a number of power lines for electricity supply generated by Tenaga Nasional Berhad (TNB). The company has owned 95% of power lines from North to South of Peninsula Malaysia. In order to maintain the quality of power transmission for the country, it is very important for TNB to monitor the stability of their transmission towers (pylons). Unfortunately, most of these transmission towers are located at very hilly and remote areas. Conducting inspection at those areas are not efficient since the staffs are exposed to wild animals, not cost effective and always require longer inspection time due to weather condition. Therefore, a new technique which is implementing a stability threshold value by installing selected sensors at the critical slope is introduced to improve the efficiency of current slope monitoring procedure. Four (4) sensors which are piezometer, inclinometer, raingauge and soil moisture probe are installed to monitor four (4) parameters that cause landslide. Based on one-cycle (1 year) of data collection, three (3) threshold values have been identified to be as an alert value for the monitoring system.

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An attenuation relationship for far field earthquakes considered by subduction has been developed. The attenuation relationship function was developed using regression analysis. The database consisting of more than 130 peak ground accelerations from seven earthquake sources recorded by Seismology Station in Malaysia have been used to develop the relationship. This study aims to investigate the new relationship attenuation to gain exact peak ground acceleration at the location on site. Based on this study, the location is a structure located at Terengganu seaside. Referring to that data provided by Malaysia Meteorological Department Malaysia, an attenuation function was developed and that function can be used for earthquake prediction.

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The pushover analysis of jacket platforms in the past has revealed that most of the collapse failures occur due to the lack of strength of the pile foundation. However, when the jacket platforms which have been collapsed due to extreme conditions were looked into, it was found that most of them had their foundations intact. These contrasting facts can be explained with the help of the phenomenon called ‘aging of piles’. Aging effects of piles have been experimentally proven to improve the pile capacity with time, but due to lack of proper understanding and suitable techniques to incorporate them, these aging effects were ignored when the pushover analysis was done. In this study, a simple technique of stepping up of the soil curves in order to accommodate the increase in capacity of pile foundation due to aging is utilised. Three different jacket platforms were employed to study the changes of Reserve Strength Ratio (RSR) after the pushover analysis incorporating aging effect of piles. The incorporation aging effect of piles has created both improvement as well as reduction in RSR of the jacket platforms. The maximum improvement in RSR was found to be about 122 % and the maximum reduction in RSR was about 12 %. The adequacy of the new pushover analysis results in explaining the actual case scenarios are also discussed. The study has provided a deeper knowledge into the behaviour of aged offshore jacket platforms.

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The sustainability of a neighborhood has a crucial role in preserving the environment for future generations. The development of neighborhoods consumes an excessive amount of land that needs to be protected. Libya must consider sustainable neighborhood indicators in its urban planning and design to allow future generations to benefit from such development. This paper focuses on issues that are related to the sustainable neighborhood indicators and development of Libya. Specifically, sustainable neighborhood development was investigated on the basis of shareholders, whereas the sustainable neighborhood indicators were examined in terms of their physical features and benefits. Results showed that sustainable neighborhood indicators of various countries are generally similar and only differ depending on their regional climate characteristics. This paper proposes several approaches for optimizing the sustainable neighborhood indicators of Libya.

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The responses of reinforced concrete beams subject to low velocity impact loading are simulated using orthotropic constitutive model incorporated with Smoothed Particle Hydrodynamics (SPH) method. The tensile failure of the beam is using the orthotropic constitutive equation during the softening phase on tension region, where the three principle strain components for tension (positive value) and compression (negative value) are used independently. In order to validate the proposed model, two impact cases were analyzed. The first case is simulation of simply supported beam without shear rebar using SPH and FEM. The second case is involving the comparisons of impact case of RC beam using proposed model with existing experimental tests. By adopting orthotropic constitutive equation and tensile softening algorithm defined by damage parameter, flexural cracks and shear failure can be analyzed by tracing the local stress condition.

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Reinforced concrete (RC) structure is a common material used in construction and exposed to excessive load over time. The load would generate cracks in the RC structure and need to be evaluated. This paper presents an acoustic emission (AE) monitoring for damage evaluation of RC beam subjected to increasing fatigue loading. The fatigue loading is subjected on the RC beam based on six loading phases. A total of twelve samples were tested using three-point loading and evaluated using AE signal strength parameter. The AE signal strength is evaluated at flexural region and shear region. Visual crack pattern appeared on the beam surface is also observed. It is found that the AE signal strength to demonstrate the occurrence of crack initiation and propagation in the tested specimen is well matched with the visual observation. Hence, the AE analysis based on signal strength provides valuable information on the occurrence of damage in the RC beam.

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Several studies have been conducted for the removal of heavy metals in literature using natural adsorbent. The study of the removalof heavy metals from raw palm oil mill effluent considered as one of the major high strength wastewater has rarely been reported. In this study, Cow bones were developed as effective carbon adsorbent. The investigation of the effectiveness of the prepared activated cowbone powder was studied for the removal of manganese ion from raw POME. The surface roughness of the prepared activated CBP was 184.471 Ra(nm) of length 0.777 µm observed through atomic forced microcope. The experiment were carried out with 100ml of raw POME under different adsorbent dosage and other fixed conditions. The equilibrium adsorption capacity of the activated CBP was determined from the relationship between the initial and equilibrium liquid phase concentrations of POME. The result of the investigation showed optimum adsorption of the manganese ions onto the adsorbent media at 15 g adsorbent dosage for sample 1 and 2 with 98.3 and 98.4 % removal efficiency respectively. The lowest adsorption capacity of the media was at 5g for both samples at average of 95.34%. The result showed activated CBP can be a very effective alternative to activated carbon for the removal of manganese from raw POME.

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The effect of eco-degradant PD04 on the properties of recycled polyethylene (RPE)/chitosan biocomposites has been investigated. The recycled polyethylene/chitosan biocomposites were prepared by using Z-blade mixer at 180°C with a rotation speed of 50 rpm. RPE was filled with chitosan at various loading of 0, 10, 20, 30 and 40 per hundred part (php). Whereas, 5 php of eco-degradant PD04 from the weight of RPE was used as degradation additive of the biocomposites. From tensile properties results, it indicates that the presence of eco-degradant has increased the tensile strength and Young’s modulus but decrease the elongation at break. The biocomposites with eco-degradant has reduced the amount of water absorption and this indicates that eco-degradant give better water resistance to the biocomposites. The scanning electron microscope (SEM) micrograph of fracture tensile surface shows that the chitosan is well dispersed in RPE matrix with the presence of eco-degradant. The filler was coated with matrix, indicates that the filler is more compatible with the matrix. The biocomposites with eco-degradant have better compatibility, dispersion and adhesion as compared to biocomposites without eco-degradant.

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Excess thermophysical properties are important in understanding the molecular interaction between unlike molecules. The excess properties data are very important for process design and separation, especially in chemical industry. The excess thermophysical properties reviewed are excess molar volume, excess molar enthalpy and viscosity. In this review, particular interest is taken on binary mixtures of fuel oxygenates which are methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), tert-amyl methyl ether (TAME) with lower alcohols. This review will enable researchers to know what are the mixtures studied and where future work is required.

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Microwave assisted hydrodistillation (MAHD) is an advanced technology extraction method that came up through the incorporation of microwave irradiation into the conventional method, hydrodiatillation (HD). In this research, both MAHD and HD methods have been compared and evaluated for their effectiveness in the extraction of essential oil from (cinnamon) barks. The effect of various parameters such as microwave power level (200W, 225W, 250W and 275W), water to raw material ration (6:1, 8:1 and 10:1) and extraction time (30 min, 60 min, 90 min, 120 min, 150 min and 180 min) on the yield of extraction and its major constituents were investigated and compared accordingly between MAHD and HD. At the optimum parameters of microwave power, 250W, water to raw material ratio of 8:1 and extraction time of 90 min, the yield obtained was 2.55% and 1.89% for MAHD and HD respectively. Gas Chromatography/Mass Spectrometric (GC-MS) used to further analyse the effect of both extraction methods by evaluating the content of its main constituents which is trans-cinnamaldehyde and oxygenated compounds. Results revealed that MAHD method possesses highly desirable features than HD and could serve as an efficient and convenient alternative to HD, especially in terms of its shorter extraction time, as well as the potentiality to produce reasonably good quantity and quality of cassia oil.

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In the wake of energy crisis and the drive to reduce CO2 emissions, the alternative energy sources are much demanded in order to reduce energy consumption, to meet legal requirements on emissions, and for cost reduction and increased quality. The direct discharge of slaughterhouse wastewater causes serious environmental pollution due to its high chemical oxygen demand (COD), Total suspended solids (TSS) and biochemical oxygen demand (BOD). The conventional ways for slaughterhouse wastewater treatment have both economic and environmental disadvantages. In this study, ultrasonic assisted- membrane anaerobic system (UMAS) was used as an alternative, cost effective method for treating slaughterhouse wastewater. Six steady states were conducted as a part of a kinetic study that considered concentration ranges of 7,800 to 13,620 mg/l for mixed liquor suspended solids (MLSS) and 5,359 to 11,424 mg/l for mixed liquor volatile suspended solids (MLVSS). Kinetic equations from Monod, Contois and Chen & Hashimoto were employed to describe the kinetics of slaughterhouse treatment at organic loading rates ranging from 3 to 11 kg COD/m3/d. The removal efficiency of COD during the experiment was from 94.8 to 96.5% with hydraulic retention time, HRT from 308.6 to 8.7 days. The growth yield coefficient, Y was found to be 0.52gVSS/g COD the specific microorganism decay rate was 0.21 d-1 and the methane gas yield production rate was between 0.24 l/g COD/d and 0.56 l/g COD/d. Steady state influent COD concentrations increased from 16,560 mg/l in the first steady state to 40,350 mg/l in the sixth steady state. The minimum solids retention time, which was obtained from the three kinetic models ranged from 6 to 14.4 days. The k values were in the range of and values were between 0.26 and 0.379 d-1. The solids retention time (SRT) decreased from 600 days to 14.3 days. The complete treatment reduced the COD content to 2279 mg/l equivalent to a reduction of 94.8% reduction from the original.

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The objective of this study is to test the robustness of a Process Analytical Technology (PAT) system design on a potassium dichromate crystallization process in the presence of input uncertainties using uncertainty analysis. To this end a systematic framework for managing uncertainties in PAT system design is used. For uncertainty analysis the Monte Carlo technique is used and implemented on two cases namely closed-loop operation using Proportional-integral (PI) control and Model Predictive Control (MPC). The analysis performed under closed-loop condition using PI control shows that the input uncertainties in the nucleation and crystal growth parameters affect the product-process performances (e.g. crystal size distribution (CSD)). Analysis of the proposed PAT system design (closed-loop using MPC controller), on the other hand, shows that the effect of the input uncertainties on the outputs (product quality) is minimized, and the target specifications are achieved, thus ensuring that the PAT system design is reliable under the considered uncertainty ranges.

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Energy, in the form of biofuel production through transesterification of vegetable oils and animal fats is rapidly increasing due to the hasty outgrowth of population and urbanization. Correspondent increase in the production of crude glycerol causes mixed effects. Sustainable biodiesel production requires optimization of its production process and drastic increase in the utilization of glycerol. To ensure high biodiesel yields and low environmental impacts, with respect to needless waste streams. Upgrading of crude glycerol to highly pure glycerol and subsequent utilization in producing value added products are emerging research areas. The production of such value-added chemicals requires new basic heterogeneous catalysts as well as optimization of the conventional catalyst materials. The clay especially mesoporous type clay have great potential as a catalyst. For present study Aluminum pillared clay (AlPC) was prepared by Al13 precursors and treated with NaOH to modify as basic which enhance conversion of glycerol to polyglycerol (diglycerol, triglycerol). The modified AlPC samples were well characterized by different latest techniques. The modified ALPC was found stable with high mesoporousity and basicity that enhances etherification reaction. The glycerol conversion and polyglycerol production yield was noted maximum 98% and 80.5% over prepared stable modified AlPC catalysts respectively. Industrially, the findings attained in this study might contribute towards promoting the biodiesel industry through utilization of its by-products.

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The increase prices of conventional energy sources particularly fossil fuels are usually based on the needs to match the energy demands which consequently accelerating the depletion of fossil fuels. Therefore, a renewable energy provides an attractive alternatives to replace the fossil fuels. One of the widely used renewable energy source is biomass waste such as wood sawdust due to its abundances and availabilities. This biomass waste can be used in gasification process in order to produce the hydrogen gas which is useful for energy production. Therefore, the objective of this paper is to develop a comprehensive integrated gasification and proton exchange membrane fuel cell (PEMFC) framework for a wide range of gasification process. The application of the integrated framework is highlighted through biomass gasification using fluidized bed by utilizing sawdust as biomass input. The biomass gasification model is developed in Aspen Plus and it is also considering the hydrodynamic and reaction rate kinetics simultaneously. The developed biomass gasification using pine sawdust is tested and the results obtained are in good agreement with literature data where the slight relative mean square erros of 0.018, 0.226, 0.726 and 0.317 for the H2, CO2, CH4 and CO respectively are achieved indicating a reliable gasification model is obtained. Subsequently the wood sawdust is used as an input and the results show 23.47% hydrogen gas has been produced from wood sawdust which is relatively higher than 20.86% of hydrogen gas produced using pine sawdust. Finally it has been shown through sensitivity analysis the hydrogen gas can be produced up to 47.37% when the temperature is operated at 900 °C and up to 34.96% when equivalence ratio is at 0.205 indicating an improved better gasification performance.

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Non-wood plants were examined as alternative fibre due to the limited origin resources in paper production. In Malaysia, Imperata cylindrica was used as renewable materials to obtain cellulosic pulps to produce paper and hence preventing the environmental problems. The chemical compositions, fibre dimension, pulp and mechanical properties of I. cylindrica were investigated for application in paper-based production. The surface morphology of hand sheet was also visualized. The chemical compositions involved in this study (holocellulose, cellulose, lignin, ash, hot water and 1% NaOH solubilities) were determined according to the chlorite method, Kurscher-Hoffner approach and TAPPI test method. Meanwhile, fibre dimension were measured following the Franklin method. The mechanical properties of the hand sheet (tensile, burst and tear indices) were measured according to the TAPPI test method. Scanning Electron Microscopy (SEM) was used to visualize the surface morphology of I. cylindrica hand sheet. The I. cylindrica has lower amount of lignin (5.67%), hot water (3.83%) and 1% sodium hydroxide solubilities (19.6%) than polished C.tataria, switch grass and Palmyra palm fruit. Although I. cylindrica contains high felting rate (139), the sheets produced showed higher tensile index (45.06 Nm/g), burst index (3.90 kPam2/g) and tear index (2.17 mNm2/g) compared to other published non-wood fibers. From SEM images, sheets of I. cylindrica contained abundant, straight and smooth fibre. In conclusion of the characteristic study, I. cylindrica is a good potential alternative fibre in the paper-based industry.

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A dynamic relationship exists between environmental conditions and the growth pattern of filamentous fungi. Growth kinetics such as the relationship between specific growth rate and the concentration of a substrate is one of the basic tools in microbiology. In such cases, a direct monitoring of the cell morphology and biomass distribution in the culture medium is potential. Hence the present work attempt to study the nutrient uptake and cell growth kinetics of a non-pathogenic fungus Aspergillus oryzae possessing the ability of bioremediation in the wasteful industrial rubber effluent. Four different models of Monod, Contois, Verhulst, and Tessier were used to investigate the cell growth kinetics in batch submerged fermentation process carried out in shake flasks. The compatibility of the experimental data fitted with Contois, Verhulst and Tessier models with the regression values are 0.65, 0.80, 0.21 and 0.84 respectively. Although Verhulst and Contois are the most suitable kinetic models to describe substrate utilization and cell growth behavior of filamentous fungi in submerged culture, the Tessier model was found best fitted with the experimental data. In the case of Monod, the maximum specific growth rate, µm and the half saturation constant, Ks were determined as 2.3 day-1 and 4.84 g/l respectively. For Verhulst, the maximum specific growth rate, µm and maximum biomass, Xm in terms of cell dry weight were determined as 0.9 day-1 and -1.5 g/L respectively. For Contois, µm was 3.4 day-1 and Ks was obtained as 4.04 g/L. However, in Tessier model, µm was determined to be 1.1 day-1 while the Ks was 54.05 g/l.

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In early years, virtual simulation tools have allowed a large set of developments, both in education and in the medical field, as in strain analysis, by using finite element methods (FEM) we can get approximations close to the reality of the mechanical behavior of an object. In medicine, specifically in the orthopedic field, it is necessary to perform a biomechanical analysis of the prostheses and of the various elements that they replace, with the aim of identifying possible failures in the tissues. Considering the above, in the following article describes the analysis of movement of the prosthetic knee simulation with elastic elements such as springs to approximate the behavior of the ligaments, including a stress analysis of the joint using finite element, where the results show a coefficient of reliable safety structure, safe from breakage.

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Chlorella zofingiensis is a prospective microalgae because it is mainly ascarotenoid producer, such as astaxanthin. However, its carbohydrates could be also as promising source ofbioethanol. Furthermore, Nitrogen stress treatment is reported used for increasing both carbohydrate and carotenoid of some microalgae. Therefore, this study aimed to increase carbohydrate and carotenoid of microalgae C. zofingiensis by using low and high nitrogen excessin the growth medium. The mediums were consisted of local compound fertilizer (farmpion), urea and ZA with a ratio of 0.25:0.5:1(lownitrogen excess medium) and 0.5: 1: 2(high nitrogen excess medium). Its cells density, carotenoid, and carbohydrate were measured every day for 7 days. The cell density was calculated using haemocytometer under light microscope. The carotenoid was measured using spectrophotometer with absorbance at a wavelength of 470, 645 and 662 nm. The carbohydrate was measured using sulfuric acid method. The results showed that the nitrogen stress treatment was able to increase carbohydrates and carotenoids approximately twice in C. zofingiensisas culture as source of bioethanol and antioxidant.

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The world’s fossil fuel sources are rapidly diminishing. Nowadays, the research and development of renewable energy is very important and using lignocellulosic materials to make biogas are the potential one. Rice straw waste was very potential lignoselulosic material because Indonesia has a lot of rice straw waste excessively. Microorganisms that can degrade cellulose, lignocellulose and hemicellulose are needed to produce biogas from rice straw waste. In this study, rumen microorganism and the combination between rumen and effective microorganism were used as a new hypothesis, and effective microorganism was rarely used in former study. The aim of this study was to compare the effect of rumen microorganism and the combination between rumen and effective microorganism to convert lignocellulosic biomass to a good quality of methane and high productivity rate. The digestion was done in a 6 liters batch digester with 60% working volume in 21 days, at 30-40oC, pH 6-7 and 1 atm. Cow dung microorganism was used as control microorganism.The highest yield and production rate of methane in 21 days were 0.6111 Nm3/kgCODremoval and 0.02505 Nm3/day respectively in 15% (v/v) of rumen. Meanwhile in 10% (v/v) microorganism combination, the yield and production rate were 0.365 Nm3/kgCODremoval and 0.00059 Nm3/day. Heating value was analyzed after stationary phase and the highest heating value was 744.72Btu/Scf in 5% (v/v) of rumen. Combustion test showed that the fire was blue. It shown that the gas produced has good quality and it can be concluded that rumen microorganism is better than microorganism combination based on the yield, production rate and quality of the biogas.

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In this study, optimization of milling parameters on surface roughness, material removal rate and cutting force during symmetrical cryogenic face milling process of tool steel ASSAB XW42 were investigeted. The milling parameters varied are cutting speed, feeding speed, axial depth of cut and flow rate of cryogenic cooling. The experimental design using a L18 orthogonal array and it is selected based on the Taguchi method. Experiments were completely randomized and repeated twice. Grey relational grade used to analyze the level of multiple responses (surface roughness, material removal rate and cutting force). Fuzzy logic was used to perform fuzzy reasoning of some performance characteristics. Experimental results show that the axial depth of cut gives the highest contribution for reducing the total variation of the multiple response, followed by flow rate, feeding speed and cutting speed. The maximum material removal rate and minimum surface roughness and cutting force could be obtained by using the values of flow rate, cutting speed, feeding speed and axial depth of cut of 0.5 l/minute, 300 m/minute, 150 mm/minute and 0.2 mm respectively.

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The characteristic of plastic which are easy made and shaped, make plastic become famous in industry. Injection molding is one of plastic shaping process that used by common industry due to its capability of mass producing of complicated plastic part. In this study, the mold cavity was designed for making tensile strength and impact specimen tests. This design was suitable with 900 ton capacity HAITIAN MA 900/260e injection molding machine. ASTM D638 was used for tensile strength specimen test standart dimension and ASTM D256 was used for impact specimen test standart dimension. The study started with draw the specimen tests, design the mold cavity such as number of cavity, layout cavity, channel system, and cooling system, and then do simulation. The parameters variance of simulation were melt temperature, mold temperature, packing pressure, and packing time. The simulation result was analyzed by using Taguchi method and ANOVA. The result of study said that this machine could have 12 specimen tests. Taguchi method had result that the best parameter of injection molding process is 180o for melt temperature, 60o for mold temperature, 70 Mpa for packing pressure, and 5 sec for packing time. ANOVA had result that the significant process parameters were melt tempaerature, packing pressure and packing time, where melt temperature was the most valuable process parameter.

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Bed load sediment transport generally depends on shear stress and orbital wave velocity near the sea bottom. Calculation of bottom shear stress is a very important step and is required as input for the most models of sediment transport. The formula of bottom shear stress of some researchers only were tested based on experimental data and still rarely used for field data due to problems in obtaining field data quality. In this paper, the bottom shear stress and bed load sediment transport formula is proposed and be modified under irregular wave condition for modelling the morphological change based on the velocity data obtained from the results of the Hydrodynamic Modelling by Mike 21 Software. This model has been validated with field measurement data with error level of 0.5% for surface elevation. The proposed method of bottom shear stress and bed load sediment transport was examined by the sediment transport and the morphological change modeled by Sand Transport (ST) modules of Mike 21 Software. It can be concluded that the proposed method could predict well. The result from the calculation of bottom shear stress and bed load sediment transport showed reasonable results when compared with the results of modeling by Mike 21 software in the area of canal water intake.

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Composite has growth rapidly in industrial applications. This research deals with epoxy-hollow glass microsphere composites since researches on it are very limited. Epoxy-hollow glass microspheres composites has advantages such as providing a light weight, low thermal conductivity and high compressive strength. This research focused on the volume fraction of epoxy-hollow glass microspheres, the curing temperature and its effect on the compressive strength of the composites. Compressive test specimen dimensions are produced according to ASTM D695, by varied hollow glass microspheres volume fraction of 0% to 30% and curing at room temperature and 90°C. This research showed that 15% volume fraction of hollow glass microspheres and curing temperature of 90°C gained the maximum compressive strength of the composites at 128.95 MPa. The maximum compressive strength is obtained due to high percentage crystallinity on composites matrix that occurred in adequate volume fraction of hollow glass microspheres and curing temperature.

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A research was conducted for the optimization of the end milling process of ASSAB XW-42 tool steel with multiple performance characteristics based on the orthogonal array with Taguchi-grey-fuzzy method. Liquid nitrogen was applied as a coolant. The experimental studies were conducted under varying the liquid nitrogen cooling flow rate (FL), and the end milling process variables, i.e., cutting speed (Vc), feeding speed (Vf) and axial depth of cut (Aa). The optimized multiple performance characteristics were surface roughness (SR), flank wear (VB) and material removal rate (MRR). An orthogonal array, signal-to-noise (S/N) ratio, grey relational analysis, grey-fuzzy reasoning grade and analysis of variance were employed to study the multiple performance characteristics. Experimental results show that flow rate gives the highest contribution for reducing the total variation of the multiple responses, followed by cutting speed, feeding speed and axial depth of cut. The minimum surface roughness, flank wear and maximum material removal rate could be obtained by using the values of flow rate, cutting speed, feeding speed and axial depth of cut of 0.5 l/minute, 109.9 m/minute, 94.2 mm/minute, and 0.9 mm respectively.

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Rolling and subsequent annealing are common processes to produce brass sheet. Cold rolling has attracted a lot of attention due to complicated deformation process that involves shear band and twinning. Debate remains on the level of deformation at which change in deformation mechanism occurs. Subsequent annealing process results in dynamic recrystallization, which is able to produce grain sizes and properties as required. Deteroriation of formability and ductility during cold rolling may be recovered during annealing. This research studied change of microstructure and mechanical properties of Cu-32%Zn (wt. %) brass during cold rolling and annealing processes. The Cu-32%Zn alloy was produced by gravity casting in a metal mold with the dimension of 110x110x6 mm3. The cast plate was homogenized at 800 oC for 5 h in an muffle furnace. The plate was then cold rolled with the level of deformation of 20, 40 and 70 % in multiple passes. Annealing of the cold rolled plate was conducted at 150, 200, 300, 400 and 500 oC for 30 minutes. The cooling of samples was performed in water. Characterization included Vickers hardness measurement and microstructural observation by using optical microscope. The results showed that slip was clearly observed at the level of deformation of 20 % together with few twinning. When the deformation was increased to 40 %, the twinning is major and some shear band started to form. Further increase of deformation to 70 %, the twinning was mostly replaced by shear band. The change in mode of deformation was followed by the increase in hardness of the materials. The annealing process after cold rolling resulted in recovery, recrystallization and grain growth. The higher the temperature of the annealing process, the speedier the recrystallization process that followed by grain growth and reduction in hardness.

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The aim of this study was to investigate the effect of fillers content on mechanical strength and failure mode of aluminium bonded with epoxy-based adhesive. Fillers used are iron ore, aluminium powder and silica with mean diameter of 100 µm. The mechanical strength and failure mode of the adhesive joints was determined by utilizing T-peel and single lap-shear tests and by using macro photo and scanning electron microscope, respectively. The effect of three different ?llers on mechanical strength of adhesive was investigated with choosing the highest peel strength and shear strength. The highest value in peel and shear tests were attained with silica and aluminium powder, respectively. The joints fail in mixed failure mode (cohesive and adhesive mode). This is shown that the joint strength depended on the adhesive properties and the bond adhesion between the adhesive and adherent.

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Lack of fossil fuel as energy resource of the world triggers a rapid development in renewable energy. Wind energy as one of renewable energy resource has a great potential to solve world’s energy needs especially in Indonesia. Nevertheless, the application of wind energy technology is remain undone due to inappropriate design. One way to solve this problem is by creating a wind turbine blade design which suits wind characteristics in Indonesia. The blade which is designed by 50% and 75% linearization optimization can capture 53% of wind energy at Tip Speed Ratio (TSR) of 5. By using Russian pine wood as material, the design is being simulated under critical wind speed condition and proved to be feasible in this relating condition with Factor of Safety of 5.43. The research method uses various theoretical calculation and software simulation; QBlade and SolidWorks. The purpose of this scientific article is a NACA 4415 Taperless Twsitless Pitch +7 wind turbine blade is applicable in wind turbine system in order to produce an affordable, compact, and efficient wind turbine blades appropriate for wind characteristic in Indonesia.

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The present study aims at investigating of factors affecting in enhancing the energy capture capabilities of performance wind turbine. The considered parameters are turbine swept area, air density, wind speed, and power coefficient as a function of pitch angle. A tool aerodynamic analysis based on the Blade Element Momentum Theory (BEMT) is developed to study the parameters that affect the power curve of blade wind turbine. The study shows that the operational parameters has a direct effect on the performance of wind turbine which will lead the developers and researchers to focus on the highest priority parameter that should be considered for optimizing the new generations of wind turbines blade.

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Shell Eco Marathon is a competition for fuel efficient vehicle organized by Shell annually for student around the word. Every team should present a uniquely designed vehicle targeted to be driven to an extreme distance using 1 liter of fuel. This study aimed to conduct a vehicle dynamic modelling by using Simulink program from MatLab to predict vehicle fuel consumption. The Model is build based on vehicle data and drive-train characteristic. To model the vehicle, various data such as body weight, tire/wheel weight and angular inertia, frontal area, drag coefficient and tire rolling resistance are collected. To model the drive-train, transmission ratio, engine torque and specific fuel consumption curves, mechanical efficiency of some rotating parts are also collected. Model of the vehicle is a close loop system in which engine as power unit gave its torque to wheel to move the vehicle. More speed developed by the engine would produce more resistance of vehicle dynamics. The calculations were conducted with changing vehicle speed, driver mode, and inclination of the track. Predictions of accuracy were done by using competition data from Sepang, Malaysia circuits within 5% of error.

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Influence of the compression ratio and injection timing on Sinjai engine performance with 50% bioethanol-gasoline blended fuel were investigated on water brake dynamometer. The properties of bioethanol were measured based on American Society for Testing Materials (ASTM) standards. Fuel consumption was measured by the time of fuel consumption per 25 cc of fuel in a measuring glass, whereas combustion air consumption was measured using an air flow meter. The emission parameters, exhaust gas temperature and air fuel ratio were measured using STARGAS exhaust gas analyzer. The compression ratio was increased from 9, 6; 10, 6 to11, 6 dan ignition timing was set for minimum advanced of spark ignition for best torque, MBT with limited by knocking. Ignition timing was adjusted for maximum torque and thermal efficiency. Engine performance testing conducted in a variable speed, starting the engine speed 2000 to 5000 rpm with intervals of an increase of 500 rpm. The engine performance parameters evaluated were torque, brake mean effective pressure, power, specific fuel consumption, thermal efficiency, exhaust gas composition and volumetric efficiency. The results showed that the increase of compression ratios improved engine performance for 50% bioethanol-gasoline blended (E50) fuel throughout all the speed range investigated. The both fuel fuel has same the tendency that the degree of the ignition timing is more advanced due to higher engine speed but the value of degree of ignition timing advanced, from 18 0BTDC at engine speed 2000 rpm until 26 0BTDC at engine speed 5000 rpm. The addition of compression ratio requiring retarded ignition timing to avoid detonation. The use of E50 fuel, at the compression ratio is 11.6 can improve brake torque, power and mep respectively by 3, 68%, 4.58% and 3.68% as compared to using pure gasoline at a compression ratio of 9, 6. While the influence of adding compression ratio at the E50 can reduce bsfc by 13, 42 % and increase thermal efficiency by 14, 67 %.

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In the design of a pontoon system as a floating supporting structure for a Sea Wave Energy Convertion System (Pembangkit Listrik Tenaga Gelombang Laut Sistem Bandulan or simply “PLTGL-SB”), the motion of the pontoon in the sea is a very important parameter. It is needed a pontoon with good motion characteristics, so that an integrated pendulum on it can steadily move with sufficient torque. In this study a 1:10 scaled model of tripod pontoon was used as a model of the prototype that has been installed in Tanjung Bumi, Madura, East Java. This paper describe the motion characteristics of the model which has been tested in a towing tank of Indonesian Hydrodynamics Laboratory (LHI) in Surabaya. The test also for collecting the test data in well-controlled condition for calibration and validation of numerical simulations. The pontoon motion measurement method using an optical tracking device that has digitally integrated. In order to obtain the pontoon responses the test was carried out on a regular wave with two variation on period which are 5 and 10 seconds and with wave height of 5.0, 10.0 and 20.0 cm. From the analysis, it was found that the tripod pontoon model has significant roll and pitch motions that suitable as a supporting structure for “PLTGL-SB”.

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This paper presents an optimization of machining parameters on the material removal rate (MRR), cutting width (kerf), surface roughness (SR) and recast layer thickness (RL) of WEDM process. Buderus 2080 tool steel was selected as workpiece material. The combinations of machining parameters were determined by using Taguchi experimental design method. The four important machining parameters such as arc on time, on time, open voltage and servo voltage were taken as process variables. Optimal machining parameter were obtained by grey relational analysis and fuzzy logic method. Experimental results show that on time gives the highest contribution for reducing the total variation of the multiple responses, followed by open voltage, servo voltage and arc on time. The maximum material removal rate and minimum cutting width, surface roughness and recast layer thickness could be obtained by using the values of arc on time, on time, open voltage and servo voltage of 1 A, 2 µs, 75 V and 30 V respectively.

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Efficiency of household gas stove has been investigated by varying the gap between pan and stove cover. The efficiency was analysed by measuring combustion energy produced by LPG, cover surface and water temperature used in cooking process. Ceramic cover was used since this cover showed the best efficiency compared to other materials in previous researches. Gap between pan and stove cover was varied in 1 mm to 7 mm with increment of 1 mm. The results showed that in certain fuel rate of 0.0125 l/s, the gap of 4 mm indicated the highest efficiency of 46.4 % because of the optimum condition was simultaneous achieved in convection and radiation heat transfer processes of the heating system.

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Hydraulic system is widely used in much application such as metal forming and press machine. The Solenoid valve is an important part of modern hydraulic systems. This paper presents a new approach of modeling and simulation of solenoid valve by using mathematical expressions for describing the spool displacement. The objective of this paper is to investigate spring constant influence to dynamic response characteristic of the spool displacement. The analysis method use modeling solenoid valve to describe physical model into mathematical models and simulation solenoid valve with the variable of spring constant and describe into dynamic response. Simulation results show that the spring constant was influence to the dynamic response. The spring constant more relevance were achieved using variable with K1 = 6,000 N.m-1 and K2=8,000 N.m-1.

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Fluid movement of liquid through a pipe arch supported by a drop in pressure caused by the inertia of the fluid and the secondary flow across the pipe bends. For Newtonian flow, pressure gradient near the wall area is the trigger for the secondary flow. Bend pipe has a value greater than the pressure drop due to the straight pipe geometry and track changes that have an impact on changes in the flow pattern to form separate flow resulting from the inner side of the pipe bends, this study aims to determine the pattern of two-phase fluid flow (water-air) and pressure drop that occurs at 900 curves. Research methods by varying the volumetric proportion of gas (ß) of 25-50%, the air discharge (QG) of 1, 2, and 3 Liter Per Menit (LPM) and water discharge (QL) that affect fluid flow pattern and two-phase flow pressure drop in the pipe bends 900. The data obtained were carried out data processing and analysis using statistical analysis. The results obtained can be concluded that the greater the proportion of volumetric air (ß) then water Reynolds number (Resl) decreases, causing friction between the large phase, due to the greater frictional force will increase the pressure drop and also cause instability water fluid (flow pattern ) in turn 900. The centrifugal force caused by the 900 turn influence on the frictional forces between the phase interfaces pressed together with the emergence of a certain thickness. The smaller the water Reynolds number (Resl), the greater the thickness of the interface, the interface thickness greater then also affect the greater pressure drop.

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