A typical time signal contain overwhelming amounts of data and some of the signal components represent for irregularity such as crack and leak which greatly important to be identified precisely instead of using traditional method. The strategy can be done using signal processing method through high-quality time-frequency representation (TFR) for analysing such time dependent signals to accurately discover these superposition signal components. A few popular TFR methods such as wavelet transform analysis and relatively new, synchrosqueezed wavelet transform were applied in current study using artificial signal. From the result, both methods successfully discover an irregularity in the signal with different degree of accuracy and it is shown that synchrosqueezed wavelet transform provide the best and detailed time-frequency representation.

Full Text

Most personal rural stalls in towns or small cities are using zinc roofs as the top shelter. The material properties itself influence the rate of temperature changes during the afternoon that typically as the peak of daily temperature. Zinc, which is the material of the roof, is a type of good absorbent and heat releasing material. The purpose of this study was to create an alternative system to cool down the area under the roof of zinc-roofed stalls in order to reduce the heat and discomfort during peak temperature periods that believed contributing in customer’s satisfaction. An alternative method proposed is the use of corrugated booth cooling system using water resources. This system use natural water resources or the river water as a major resource to cool down the zinc roof which then the space under the stall. The use of river water is natural water gushing and will prevent water shortages. The system sprinkle water on the zinc roof using water sprinkler. This study will analyze two types of data measuring the effectiveness of this system by temperature difference, which is in the space under the stall’s roof temperature. Two analyzed spaces divided which are installed system area and space that not installed with the cooling system. The purpose of this two separation data is to compare the temperature differences in the studied area. The system is environmentally friendly and has aesthetic value to afford comfort for the customers.

Full Text

The fast Fourier transforms (FFT) is commonly applied in transformation of electromyography (EMG) signals from the time domain to the frequency domain. However, this technique has a limitation to provide the time-frequency information for EMG signals. This paper presents the analysis of EMG signal for contraction of muscle activity by using spectrogram. Spectrogram is one of the time-frequency representations (TFR) that represents the three-dimensional of the signal with respect to time and frequency in magnitude presentations. The contraction of muscle activity was based on manual lifting of a 5 kg load performed by the right biceps brachii at lifting height of 75 cm and 140 cm. Ten healthy volunteers in fresh condition participated as subjects to acquire raw data of EMG signals. The raw data of EMG signals were then analysed using MATLAB 2011 to obtain the TFR. Based on the TFR, this study obtained the instantaneous RMS Voltage (Vrms(t)) to visualize the trend of the EMG signals performance in window size of 1024. Results of this study evince that the lifting height of 140 cm obtained higher Vrms than 75 cm. It concluded that the application of spectrogram is able to counter the limitation of FFT in providing the time-frequency information for EMG signals.

Full Text

Ultrasonic testing has variety of usage. In composite laminates material, it has been use for defect detection such as flaw, un-bonded, void, micro crack, foreign material occurrences and thickness measurement. In this study, glass fiber composite laminates (GFCL) being used and produced in-housed with dimension 120 mm length x 80 mm width x 2.4 mm thickness. It consist an artificial defect which was drilled 6 mm in diameter. Ultrasonic range finder transducer with frequency 42 kHz and single crystal immersion transducer with frequency 2.25 MHz have been applied in order to study the performance between both transducers. During measurement, gap distance between specimen surface and both transducer had been fixed at 10mm. Moreover, linear motion at x-axis with constant speed being controlled during measurement process. Measurement data from ultrasonic rangefinder and single crystal immersion transducer had been compared to determine the accuracy between both transducer. All the data are required in order to develop ultrasonic scanning unit that applicable for those transducer. However, some experimental data need to be analyze before further development to avoid misleading especially on operational and functionality of ultrasonic scanning unit.

Full Text

This study was conducted to determine the potential of electrical energy of rice husk as fuel for power generation in Indonesia. The estimated potential of rice husk in each province of the country was calculated using the statistical data of rice production from 2011. The estimated annual potential of rice husk development was calculated using statistical data from 2001 to 2012. The results indicate that the development potential of rice husk, potential for electrical energy and economic potential increased by approximately 36.8% over 12 years; an average of about 3.1% per year. In 2011, the 33 provinces had rice husk potential of around 10.52 million tons, which is equivalent to about 5.24 million tons of coals, providing electrical energy and electrical power potentials of about 39,272 GWh and 4, 481 MW, respectively. About 26 provinces had potential rice husk electrical energy greater than 100 GWh, providing a total electrical energy potential of approximately 39,076 GWh, and electrical power of around 4, 460 MW. This potential could be turned into fuel for small power plants with mono-combustion applications. The other seven provinces had very small rice husk potential and should apply co-combustion with other fuels for very small power producers. Use of rice husk as fuel for power plants could overcome the shortage of electrical energy, reduce the use of coal and decrease negative environmental impacts in Indonesia.

Full Text

Studies were carried out on the force profiles of the pneumatic electrode actuation system and servo electrode actuation system to analyse their effects on weld strength. The studies were carried out at three different locations of the weld lobe; below the lower limit, between the lower limit and upper limit and above the upper limit. Servo electrode actuation system was able to produce weld with better strength compared to the pneumatic electrode actuation system within the weld lobe, due to its ability to produce high resistance for the same welding current. Below the lower limit, servo electrode actuation system was able to produce a sound weld with the use of a low welding current combined with a preferred failure mode. Similarly above the upper limit, servo electrode actuation system was able to produce a weld with high current and without the occurrence of expulsion. Finally, it was observed that with the servo electrode actuation system, the width of the pneumatic electrode actuation system’s weld lobe can be improved to an extent.

Full Text

Poor indoor air quality (IAQ) caused many problems for human; those problems can be classified into health problems which reduce the efficiency and output especially in workplaces. For example, health problems, like asthma and pulmonary inflammation, lead to low attendance level which affect the output. The main purpose of this paper is to review scientific literature on air filtration system effectiveness in improving indoor Air Quality (IAQ). These studies include topics such as: chemical, biological, gases, particle and bacteria. Indoor air pollution emitted by occupants, equipment, furniture and building are also included. Portable air cleaning, filtration system and ventilation methods application in HVAC system, recent research relating filtration type and ventilation used in laboratory environments and the large space applications are also reviewed. The scope of studies investigated includes appropriate air filter technology and the compatibility between cost, the health problems, energy consumption and its relationship with filter pressure drop. Future studies are suggested to focus on cleaners and air filtration, ventilation and energy consumption in office buildings.

Full Text

A high strength steel sheet is used to make the hollow sections for the body structure of automobiles. The hollow sections, which are typically joined by resistance spot welding, have insufficient energy absorption because the joins are not continuous. Thus, to overcome this problem, the hollow section is joined using the hemming process. The hemming of the high strength steel sheet was successfully performed using punch with stopper. The high strength steel hollow sections joined by hemming and resistance spot welding were then examined by tensile and fatigue tests. The hollow section with hemmed joins showed better performance in both tests. The overlapping joins of the hemmed hollow section have greater strength as compared to the resistance of spot welding joins.

Full Text

This work presents the effect of impactor geometries on the low velocity impact response of kenaf reinforced composites. In this work, three layers of unidirectional layers yarn are stated together to form [0°/45°/0°] fiber orientation. The composites are hardened with polyester origin under compression in a steel mould. The stand samples plates of 100mmX100mmX 100mm are perforated using three different types of impactor geometries such as flat, cone and hemisphere. It is found that, higher energy absorption are showed using flat impactor compared with other. It is also found that normally perforated produce higher energy absorption compare to obliquely. However, flat impactor result severe composite fragmentation compared to other impactor geometries.

Full Text

In this paper a classification and analysing of commercial and synthesized additives used with biodiesel by different researchers was conducted. Biodiesel is widely accepted as an alternative fuel comparable to petroleum diesel in compression ignition engines. It is relatively poor cold flow property is a characteristic which limits its application. Here, fuel additives become the most viable choice not only to decrease this drawback but also to produce specified products that meet international and regional standards. This article covers a deep and through literature review of the effect of different additives on biodiesel properties, engine performance, and emission characteristics. The additives usage in biodiesel is inseparable both for improving the cold flow properties and for better engine performance and emission control. It can be concluded from the literature that specific additives for biodiesel remain at their infancy. Further research is needed to develop biodiesel specific additives.

Full Text

Lightweight and thin-walled cold-formed steel section has become a popular material in building and engineering application. Cold-formed steel sections are available in a variety of thickness, shapes and steel grade. Continual researches have been carried out world widely for cold-formed steel sections with straight profile. However cold-formed steel section with curved profile, which serves both esthetic and engineering purposes for arch and truss structures, has not been studied in depth. This study aims to investigate the flexural behavior of cold-formed steel channel section with curved profile. Cold-formed steel channel (CFSC) with lips and intermediate stiffeners is selected. The CSFC is cut and bended by clamps, forming into cold-formed steel channel curved section (CFSC-CS). Six specimens of CFSC-CS with different weld and screw profiles are prepared, together with one CFSC section without curved used as controlled specimen (CFSC-NS). The bending behavior, vertical deformation and horizontal deformation of the seven CFSC specimens are determined experimentally. From the results, the flexural strengths for all CFSC-CS specimens are lower than CFSC-NS, with percentage of strength reduction range from 8.79 % to 38.80 %. Among the six curved sections, CFSC-CS with three spot weld locations (CFSC-CS3) indicated the highest ultimate load, i.e. 6.484 kN. CFSC-CS3 shows a potential to decrease the vertical flange and horizontal web deformation, and is capable to protect the section from the flexural torsional and local buckling.

Full Text

Abstract:

Laterite soil is commonly considered as a good natural foundation and building material. This type of soil is found in abundance in most of the tropical countries including Malaysia. In any project, the properties of laterite soil are determined through borehole sampling which is the actual determination of the subsurface soil but on contrary it is very expensive and time consuming process and also requires too much effort. Therefore, in order to save cost, time and energy, electrical resistivity method is an alternative method which could provide quick and rapid assessment of the subsurface soil without causing any disturbance to the soil and thus much time and money could be saved. In this research paper, a conceptual model for the assessment of strength properties of compacted laterite soil has been proposed based on the correlations of soil properties mainly cohesion and angle of internal friction with electrical resistivity values. The results analyzed from the study hopefully will contribute for the possible assessment of the electrical resistivity method to be used for the determination of geotechnical properties of laterite soil in geotechnical calculations such as factor of safety (FOS) and bearing capacity.

Full Text

Construction of structures on soft soils gives rise to some difficulties in Malaysia and other countries especially in both short and long term deformation. The most critical geo-environment challenges are excessive settlement and in particular differential settlement leading to hazardous and discomfort in road usage (bumpy road) and structural distress (differential crack) in buildings. The settlement studies in soft yielding soil require effort, time and expense through field and/or physical model testing. Thus software modelling is a better and faster alternative to solve many such problems with varying parameters. Concepts in the prediction and observation in physical modelling using cellular mat are presented.

Full Text

Urban transportation planning has a key role in the daily routine of inhabitants. Transportation planning has been observed as the most debatable subject, but least attention has been paid on it. Traffic congestion is expanding up to the outskirts of city centers during peak hours. It is perceived as an unresolved urban transportation problem for the inhabitants of urban areas such as Karachi. To resolve this issue, park-and-ride service (P and RS) is considered as a sustainable approach and major contributory in urban areas to reduce the traffic congestion from city centers. P and RS has been successfully implemented and became beneficiary in many countries of the world. Particularly it helps to reduce traffic congestion at a city center, and as a result it reduces the reliability of private vehicles. The objective of this research is to develop a model to shift car travelers' towards P and RS and study the factors which influence car travelers' choice of mode. This study can help stakeholders with useful information for future planning and development of P and RS in Karachi, Putrajaya and Surabaya. The findings revealed the reasons, why car travelers are discouraged to use P and RS facility. Discrete choice modelling is discussed to analyze the factors that encourage users to switch their mode choice towards P and RS. Research outcomes will support policy making and provides base for the future study on the mode choice model for P and RS.

Full Text

Geo-electrical assessment is an appealing instrument for depicting subsurface properties without soil unsettling influence and also can be considered as an intermediary for the spatial and fleeting variability of numerous other soil physical properties (i.e. structure, water substance, or liquid synthesis, porosity, degree of saturation etc.) and strength parameters (i.e. cohesion and angle of friction). Since the system is non-dangerous and exceptionally delicate, it offers an extremely fascinating apparatus for depicting the subsurface properties without burrowing. In this paper a conceptual model is developed for the assessment of slope stability and FOS using electrical resistivity values of the insitu soil at controlled moisture content (30%). The obtained results will be interrelated with soil physical properties (moisture content, plasticity index, specific gravity, porosity, degree of saturation etc.), chemical properties (Cation exchange capacity (CEC), pH and mineralogy) and strength parametres of soil such as, cohesion and internal angle of friction. Assessment of geotechnical hazards will incorporate by applying 1D electrical resistivity survey on a laboratory scale using fabricated soil box. The established results will hopefully contribute in the calculations of bearing capacity, slope stability and factor of safety for soil.

Full Text

The construction of the highway network in Malaysia is growing rapidly along with the toll plazas facilities and safety constructions such as toll plaza barriers. However, the issue of accidents involving crash barriers at toll plazas turns into horrific nightmare for road users. It have been investigated that accidents at the toll plaza gates due to impacts of the vehicles with concrete crash barriers with results in damage and fatalities. Therefore, the following study is to conduct a simulation test for crash barrier Tensile Wire Fracture toughness (TWFT) system. TWFT system that used hot rolled galvanized steel materials with small displacement rate of 4.0 x 10-4 m which was considered suitable as a replacement for the existing concrete crash barrier. The data analysis were generated by the software Elfen. The graph of displacement, direct shear and effective stress were generated as for the hot-galvanizes steel material model. Elastic energy, kinetic energy and inelastic dissipated energy were compared between these two materials. The results shows that the hot-rolled galvanized steel have the energy to return the material to its original form and the level of damage shows that the concrete material failure are greater than the hot rolled galvanized steel materials. In conclusion, the material for a new alternative crash barrier is likely to reduce the rate of death due to accident and damage with regards to road furniture's and vehicles.

Full Text

Green building is an environmentally sustainable building that created by using the processes that are environmentally responsible from the initial stage of planning to the design, construction, maintenance, renovation and last but not least the deconstruction of the building. The green buildings also known as a high performance and a well-designed building that will save money and create healthier environments for people to live and work which through an improved indoor environmental quality and thermal comfort. Nowadays, the green building is being evaluated by using various sustainable rating tools that available worldwide focusing on different areas of sustainable development and are designed for different types of projects and climates. These tools include energy systems assessments, management of building, indoor environmental quality, site planning, maintenance and many more. Hence, the objective of this paper is to provide a literature overview of various sustainable rating tools available worldwide in relation with the indoor environment quality aspects centering on the indoor thermal comfort. The paper wills emphasis on the sustainable rating tools criteria in three (3) tabulated summary form that will deliver better understanding on the relationship between the rating tools, the indoor air quality and the thermal comfort aspects in all selected green building’s sustainable rating tools.

Full Text

Noise pollution is one of the major threats in many countries that affect our quality of life. This problem can cause negative effect to human hearing, disturbing emotion as well as individual behavior. Noise can be treated and control by applying sound insulation or sound barriers at affected areas. Many studies attempt to optimize the use of natural fibers as sound insulation materials replacing readily available synthetic products in the market. Natural fibers such as rice straw, coconut coir, palm oil, tea-leaf, kenaf, hemp, bamboo, cotton, wood particle, wool and clay is biodegradable, renewable, cheap and give less potential risk to human health. Utilization of these materials as sound insulation product will give practical solutions in waste management issues. This paper review on the factors that influencing absorption performance of natural fibrous sound absorbing materials. Physical properties such as fiber thickness, density and porosity are the main factor that contributes to sound absorption performance of natural fibers. It was found that most of natural fibers are capable to absorb sound in wide range of frequencies. Thicker panels are good for low frequency application while thinner absorbent is best for high frequency. Moreover, denser materials absorbed more sound energy compared to less dense materials. Significant effect on sound absorption performance was also given by materials with less porosity compared to materials which have more pores.

Full Text

Sustainability is a concept that encompasses a wide range of social, economic and environmental issues. It can also be express as a concept of responsible stewardship that incorporate systems that meet the needs of the present without compromising the future needs. The sustainable design does not only enhance the positive result of the environmental but also reduces the overall life cycle cost of building and increases the occupant’s comfort thus help in creating a sustainable community around the world. Subsequently, this paper will delve into the aspects of sustainable and green construction in general. It will also describe on the significant of building the design in optimizing the occupant’s comfort in a building. Through a literature review, this paper will discuss the roles of sustainable standard tools in the construction industry. Nevertheless, this paper will also deliberate the findings from the previous study in areas of building façade, indoor environment quality, thermal comfort, occupant’s satisfaction and green building. At the end of this paper, the author will describe the future direction and the expected contributions of her in-progress research.

Full Text

Fire is one of the most severe natural disasters that a structure needed to face. Therefore, this study focused on post-fire repair of concrete-filled double skin steel tubular (CFDST) columns using fiber reinforced polymer (FRP). There are two types of repairing scheme that is discussed in this study, single and Hybrid FRP. Prior to being repaired, the CFDST columns were subjected to fire following ASTM E-119 standard fire curve until the temperature reached 600°C. Then, the temperature was kept constant for two different exposure times, i.e., 60 minutes, 90 minutes. Both single and Hybrid FRP enhanced the ultimate strength, secant stiffness and Ductility Index (DI) of fire-damaged CFDST columns.

Full Text

Plastic bags have become an essential part of people’s lives. Hence, the amount of plastic bags used annually has been growing steadily. In this two-part study, the mechanical and physical properties of three different types of plastic bag aggregates were described. These lightweight plastic aggregates were then used as substitute for natural aggregates at percentages of 0%, 3%, 6%, and 9%. Recyclable plastic bags measuring 10–20 mm were gathered then heated in an oven at approximately 150 °C for nearly 10 min. The first part of the study investigated the properties of the three different types of plastic bag aggregates and those of normal aggregates in terms of aggregate impact value, aggregate crushing value, specific gravity, and water absorption. The second part involved a compressive test on the different concretes and a comparison of the results with those obtained for the control concrete. A significant improvement in compressive strength was observed in the concrete mixes that contained 6% directly heated plastic bag aggregates and 6% and 9% glass-covered plastic aggregates. These aggregates were found to be a feasible replacement for coarse aggregates used in conventional concrete.

Full Text

Steam-enhanced extraction has been reviewed by many researchers as an innovative technology to remediate dense non-aqueous phase liquid (DNAPL) from subsurface. However, the application of steam-enhanced extraction to heterogeneous subsurface conditions is still obscurity and its implementation is limited due to steam flow sensitivity to site characterization. Two-dimensional (2-D) simulations were performed to assess the efficiency of steam-enhanced extraction in remediation of heterogeneous subsurface contaminated with tetrachloroethylene (PCE) spill. The simulation was performed with four different steam injection rates. The results shows that increased in steam injection rate will increase the PCE remediation time. The steam injection with the rate of 1.0 x 10-4 kg/s was successfully removing 100% of the PCE. There are significant impacts in the difference in remediation time with the increment approximately 20 min, 40 min and 70 min for every 2.0 x 10-5 kg/s increment. The dominant mechanisms of PCE removal is physical displacement through vaporization and co-boiling enhanced by steam distillation and steam stripping. The simulation results of steam-enhanced extraction for PCE removal was compared with surfactant-enhanced method implemented in existing experimental study. It was discovered that the time required to remove PCE using steam-enhanced extraction is four times faster than the time required to remove PCE using surfactant-enhanced method. This shows the capability of steam-enhanced extraction to recover contaminant more effectively. Steam-enhanced extraction has a greatest potential to decrease clean-up time which will offset greater capitol cost of the system.

Full Text

Anaerobic wastewater treatment can be used as an effective treatment for chicken wastewater considered as medium strength wastewater. In this study, up flow anaerobic sludge bed (UASB) and hybrid-UASB (HUASB) reactors were combined with aerobic treatment using aerated lagoon (AL) for the treatment of chicken wastewater. It involves the use of steel slag as a filter material in the HUASB reactor. The objectives is to investigate the effects of the temperature, sludge bed development, and removal rates of pollutant during the operation. Three reactors were used in this study, R1 and R3 operated at ambient temperature (26±3°C) and R2 at thermophilic temperature (50±5°C). R1 and R2 were filled with seed sludge up to approximately 50% of their volumes also steel slag filter medium were installed into the top halves of the R1 and R2 reactors. R3 was seeded with sludge only (no filter medium was installed) and all reactors were operated continuously. From the observation, the BOD decreased to a minimum of 20 mg/L at earlier increase of OLR from 0.78, 1.07, 1.52 and 1.95 g.COD/L.d. The pH was found to be in the range of 5.50 to 9.00 which may inhibit biogas production. The combination of UASB/HUASB with AL has the highest of 88% percentage of COD for R1, 91% COD removal for R2 and 84% for R3. Also there was pH increases for R3 and decreases for R2 and R1 due to different OLR. The combination of the reactors has proven to be an alternative treatment method for chicken wastewater.

Full Text

Shoreline and mangrove form a dynamic ecosystem to coastal area. They support and supply various foods and protections for the purpose of environmental friendly and biological balancing around the world. A dynamic phenomenon like shoreline requires the presence of spatial and temporal data to represent and visualize the object’s shape and their positions over time. This study is significant to provide a first view of the interaction and response of mangrove species to shoreline change. It utilized the use of multi-sources spatial data to provide shoreline positions between 1997 and 2011. GIS technology along with remote sensing has been proved to be a potential approach to integrate multi-sources spatial data thus enables the derivation of multi-dated shoreline positions. Statistical computation using Digital Shoreline Analysis System (DSAS) was applied to determine the rate of shoreline change along the Coast of Kukup Island. Findings show that the shoreline along the northwest of island appeared to move backward with the rates of shoreline erosion varied between 5.45 m/yr and 9.33 m/yr. However, accretion activities occurred along the northern and eastern areas of island ranged between 0.05 m/yr and 4.58 m/yr. Mangrove profile study revealed that Rhizophora apiculata was the dominant species inhabit along the shoreline of Kukup Island. Comparison of Rhizophora apiculata physical characteristic and shoreline change rates demonstrated a significant correlation, suggesting that the maturity of mangrove trees found in the area help to reduce the erosion effects. The species that equipped with various advantages enable this mangrove to survive the harsh conditions that come from the ocean and terrestrial. Therefore, the integration of GIS, remote sensing, and statistical method has efficiently improved the analysis of shoreline change and mangrove response due to its cost-effectiveness and data maintenance.

Full Text

The primary objective of this study is to evaluate optimum bitumen content and the characteristic of recycled polyethylene terephthalate (PET) as partial fine aggregate replacement in asphalt mixtures for road pavements by determining the rutting, fatigue and stiffness properties. The percentage of recycled PET replace fine aggregate in asphalt mixture start up 25% and bitumen content start from 4 to 6% of weight of asphalt mixture. The recycled plastic substitute aggregate of sieve size aggregate between 3.36 and 1.18 mm content as follow with hot mix asphalt wearing course 14 (AC 14) in Standard Specification of Public Work Department (PWD) of Malaysia. The Indirect Tensile Stiffness Modulus Test (ITSM) was used to determine the optimum bitumen content of modified asphalt mixture and followed by the Repeated Load Axial Test (RLAT), and Indirect Tensile Fatigue Test (ITFT) both at 1800 cycles to investigate the rutting and fatigue properties of PET modified asphalt mixture consist of optimum bitumen content. The result shows the highest value stiffness modulus of 0% PET modified asphalt reach at 5.5% bitumen content. All the PET modified asphalt appears to be capable in resist rutting of road pavement. Meanwhile 5% and 15% PET modified asphalt show more fatigue resistance than unmodified asphalt at 1800 cycles. In conclusion, the 5.5% bitumen content and additional 5% replacement aggregate of recycled PET plastic on asphalt mixture would enhance all engineering properties of asphalt mixture for road pavement.

Full Text

Multichannel Analysis Surface Wave (MASW) measurement is one of geophysics exploration techniques to determine the soil profile based on velocity. Meanwhile borehole intrusive technique identifies the changes of soil layer based on SPT N value. Both techniques were applied at the University campus test site and Parit Jelutong as part of soil investigation. A 7 kg of sledge hammer was used as source, 24 units of 4.5 Hz geophones used as detectors (receivers) and Terraloc Mark 8 ABEM was used as a recorder. SeisImager software was used for seismic data processing. The MASW test configuration was 5 m geophones spacing and 5 m source offset distance at Parit Jelutong, and used 1 m geophones spacing and 2 m offset distance at the University campus test site. All the MASW test array was conducted near to the boreholes. The reliable seismic results at Parit Jelutong were from depth 0.5 m to 14 m and 3.7 m to 27 m the University campus test site, respectively. Comparison between MASW and borehole data indicates that a very soft clay shear wave velocity is below than 165 m/s, soft clay at 170 m/s to 195 m/s and firm layer at 194 m/s to 317 m/s. There was not available shear wave velocity result of hard material. In conclusion, the MASW technique is potential to adapt in soil investigation to compliment the intrusive technique, which is non-destructive, non-invasive nature and relative speed of assessment.

Full Text

This article is focused on determining the Passenger Car Equivalent (PCE) values at different location that divided into road segment and locus. The PCE values are needed to analyse the traffic flows of roads in mixed traffic condition, and differing geometric or environmental conditions. Traffic conditions consist of type and dimension of vehicles, number and percentage of vehicles, time headway, speed and delay. Generally, environmental condition is discussed together with the geometric. These conditions are related to types of road, alignment, characteristics of lanes, design speed, road surface, weather, roadside activities (pedestrians walking and crossing, traders, parking, buses stopping, and slow vehicles). This study aims to develop the model of the PCE values at different segment and locus, and to find the significance of the differences of those values. The basic hypothesis is that the difference will be significant if too different conditions of locations, but it will not be significant if nearly the same conditions. This study is part of the research carried out at nine urban road segments in three cities in Indonesia. Each road segment was divided into four loci corresponding to the locations of camcorder, namely Locus B (before), Locus Z (at zebra crossing), Locus A (after) and Locus O (outside area). The PCE values were analysed by using multi linear regression model that consist of the speed ratio, dimension ratio, percentage of vehicle ratio, and side friction factoras independent variables. Finding so far shows that the standard deviation is nearly same each locus, but there is very noticeable difference each road segment. This is indicated that group data per locus tend to have the same or insignificant difference mean, while group data per road segment, either same or different mean is possible occurred.

Full Text

The production of sewage sludge (SS) from waste water treatment plant is increasing all over the world. Disposal of sewage sludge is becoming a serious environmental issue to our society. Sewage sludge which contains high heavy metal is no longer suitable to be used as fertilizer. Besides, the land fill, which is the main disposal method, has also posed threat to leachate of heavy metal from the sewage sludge to the soil. Due to fast urbanization, the demand of cement has increased alarmingly. This will lead to increased cement production and emission of carbon dioxide because the cement industry one of the major contributor of carbon dioxide emission. Hence, the research for replacement of cement using sewage sludge ash is essential to reduce both the emissions of carbon dioxide and the disposal problem of sewage sludge ash. In this investigation, sewage sludge ash has been used as partial cement replacement in concrete. The sewage sludge is incinerated at the temperature of 600°C and duration of three hours. The incinerated sewage sludge ash is sieved through sieve size of 150 µm. Four different percentages of sewage sludge ash (SSA) is used to replace the cement in the concrete. XRD and XRF tests were carried to compare the result between SS, SSA and cement. The tests conducted on concrete in this investigation were slump test, water absorption and water absorption. Results show that SSA has the potential to replace cement since there are high similarities in major chemical component of SSA compared to cement. The replacement of cement in concrete with 5% SSA has shown lower water absorption and increase compressive strength of concrete up to 10% as compared with the control samples.

Full Text

Construction industry is a main contributor to the development of the country. It is vital to ensure the performance of this industry meeting the minimum standards and client requirements. Several studies mainly in developed countries such as Australia, Unites States, and United Kingdom have demonstrated that satisfaction level among the construction players is critical particularly in terms of project performance. Satisfaction on project performance is significant to the players as failure to meet their needs may lead to project delays, cost overruns, poor quality, disputes and conflicts. Nowadays, in Malaysia, construction players are encouraged to shift from the conventional method of construction to Industrialized Building System (IBS). This method is also known as prefabrication has an ability to minimize on-site works and increase the building quality in a controlled environment. However, the take up rate of IBS in developing countries is still low as compared to developed countries. This is due to lack of technical knowledge, negative perceptions and unsatisfactory on its implementation among the contractors. A subjective performance measurement by measuring contractor satisfaction may help to improve their satisfaction level by providing a better understanding on the benefits of IBS. A broad range of satisfaction factors, as perceived by researchers and practitioners, was identified through comprehensive literatures. A questionnaire survey was carried out to examine the relative significance satisfaction factors for contractors in IBS implementation. The analysis showed that there are 36 factors have significant impacts in improving their performance in IBS implementation. Additionally, all significant factors have a correlation with eight performances of a contractor namely 1) cost performance, 2) time performance, 3) product performance, 4) design performance, 5) safety performance, 6) profitability, 7) business performance and 8) relationship performance. Further research will develop a systematic framework based on findings from this paper. It is expected that the framework can serve as a guide to develop appropriate guidelines that will aid the owners to make decisions in selecting appropriate contractors which able to complete proposed IBS project.

Full Text

Electro-hydraulic actuator (EHA) system is highly non-linear system with uncertain dynamics in which the mathematical representation of the system cannot sufficiently represent the practical system. Nonlinearities of the system come from either the system itself or external disturbance signals. These dynamic characteristics are the reasons that cause the controller design for the system to be quite challenging. In this paper, back-stepping controller design for tracking purpose of this system is presented based on Lyapunov stability condition. Gravitational Search Algorithm (GSA) technique is then used to optimize the control parameters in order to achieve a predefined system performance. The performance is evaluated based on the tracking output and the tracking error between reference input and the system output. The results show that the system’s output follow the reference input given but the tracking performance is influenced by the condition of the system and number of agents and iteration in the algorithm.

Full Text

This paper discusses on the experimental validation of an Altitude control for quadcopter. The paper describes the analysis of automated altitude control for quadcopter in real time. The controller was designed by considering all the physical parameter that required in the mathematical model. The autonomous altitude controller has been designed using Mat-lab Simulink. The paper examines PID controller in implementation of automated altitude control for quadcopter. On the other hand, for the real time application, the PCI-1711 data acquisition card is used as an interface for controller design which routes from Simulink to hardware. This experiment showed the controller designs are implemented and tuned to the real system using Real Time Windows Target approach by Mat-Lab Simulink. The proximity sensor is required to detect the height in the control system, and it requires some filter to stabilize the signal and make it reliable for their maximum distance measurement. Therefore a low pass filter will be designed for this purpose. All the result will be discussed.

Full Text

The laser drivers are extremely important to be used to provide safe interface for the optical components attached to the laser. In this paper, energy efficient laser driver circuit is design using field programming gate array (FPGA). The laser driver is first designed using current mode logic (CML) technique, which is widely used for designing the optical components. Then this design is implemented on FPGA using very large scale integration (VLSI). The laser driver produces the energy efficient output using voltage scaling technique in which the core voltage of FPGA virtex-7 board is reduced from 2.2 V (Peak core voltage of FPGA) to 0.5 V (base voltage of FPGA). By reducing core voltage of FPGA virtex-7 from peak to base voltage the power consume by laser drivers is reduced up to 90% for 15 THz frequency. Similarly, for less than 15 THz frequencies the power consumption is also reduced. The main advantage of designing this energy efficient laser driver is that it will control the output of any high frequency semiconductor laser up to 15 THz frequency. This energy efficient design of laser driver will be integrated with high frequency semiconductor laser to produce green optical output for communication systems.

Full Text

The Malaysia Electric Supply Industry (MESI) has been a regulated monopoly for many years. Tenaga Nasional Berhad (TNB) is vertically integrated from generation to distribution. Since 1992, Independent Power Producers (IPPs) and competitive bidding is introduced, which has opened for a level playing field in the generation sector, while others remained the same. Therefore, MESI had applied the single buyer model until today. In 2005, MESI has aimed to change its structure to a wholesale market model. Now, the single buyer model had passed several processes of evolution, but it still a form of imperfect competition because there is only one buyer and many sellers of a product. Thus, other alternatives of electricity market models have been proposed to carry on the MESI previous plan towards restructuring. This paper discusses three electricity market models; single buyer, pool, and hybrid market model. The case study is carried out to compare the three market models in term of generation revenue. Four busses of generator power plant have been chosen for the case study. Single buyer model shown an unfair trading. The generators can still generate revenue even without any contribution to supply the load demand and gained the largest revenue due to the existence of both capacity and energy payment. Furthermore, this market does not provide competition due to long term agreement. Thus, the results show that the single buyer is the most profitable for generation revenue compared to other market model due to capacity payment regardless the usage of real capacity based on the demand. Nevertheless, the pool and hybrid market model provide a fair trading as it based on energy bid price only.

Full Text

This paper investigates the transmission characteristics of ring loop FSS. Numerical study regarding the electrical characteristics using an equivalent circuit is developed. The FSS is optimized to operate between 8 to 12 GHz frequency range. The ring loop provides -10 dB bandwidth of 35 % (8-11.5 GHz). The simulated results are in good agreement with the measured results therefore validating the reliability of techniques using free space measurement. This provides additional guidelines for designing FSS with specified transmission characteristic for radome applications.

Full Text

Low Power RF Based Real Time Monitoring System is a wearable tracking and monitoring system targeted at the workers who were deployed in a hazardous environment, for instance mines, tunnels, off shore oil and gas fields, etc. Aim of this work is to provide the employers a means to track and monitor their solitary workers in hazardous environment, and to create an environment where the worker himself no longer experiences loneliness or reduce the risk factors. As the workers are alone, the hazardous environment might create lack of confidence in workers and results in feel vulnerable. The monitored parameters, location and safety conditions, facilitates the system to create a safe environment and provide assistance in any emergency. This system consists of two parts, which is hardware; that includes microcontroller, a display, input and software part consists of GUI, for tracking and monitoring location and motion of workers. Each worker is equipped with a device to grab the location and safety parameters. When there is no motion for more than ten seconds, a warning will be generated “NO MOVEMENTS”. The warning message triggers the safety mechanism to take rescue measures.

Full Text

The dielectric properties of a microwave absorbing material represent the ability of the material to absorb microwave signals and dissipated those signals as heat. Carbonaceous materials are preferable to be used as microwave absorbing material due to their excellent dielectric properties. In this paper, coconut shell in powder form was used as the carbonaceous material and the composite samples were prepared in epoxy resin matrix. Five different ratios of coconut shell: epoxy resin (30:70, 40:60, 50:50, 60:40, 70:30) were prepared in order to investigate the effect of carbonaceous material composition on the dielectric properties measurement. Composites with smooth and rough surface textures were fabricated in order to investigate the effect of surface texture on the dielectric properties measurement. Carbon, hydrogen, nitrogen and sulphur (CHNS) elemental analysis was performed to determine the carbon composition in coconut shell powder. It was evaluated that the coconut shell powder possesses 48.37% of carbon composition. The structural characteristic of the coconut shell powder particles and surface texture were examined using scanning electron microscope (SEM). Presence of irregular shape particles with macropores range (1 µm) porosities was detected in the coconut shell powder. Presence of uneven surface with air gap of approximately 60 µm in diameter was detected on composite with rough surface. Experimental measurement on the dielectric properties of coconut shell-polymer (CSP) composites was performed by using open-ended coaxial probe method over microwave frequency range of 1-8 GHz. It was found that the surface texture of the composites influenced the measurement accuracy of the dielectric properties. From the experimental results, composites with smooth surface texture exhibit statistically significant accuracy of dielectric properties measurement (real part) with error bars that are less than 5% (er’= er’± 0.05|er*|), compared to rough composites surface where the error bars exceeded 5 %. The measured dielectric properties for composites were directly proportional to the composition of coconut shell powder. The optimum range of dielectric properties at er’ (3.599-3.966), er” (0.381-0.572) and tan d (0.101-0.152) was measured for composite with 70 wt% coconut shell powder composition. The electrical conductivity of the composites increased accordingly as the composition of coconut shell powder increases over frequency of 1-8 GHz. The prepared coconut shell-polymer composites can be utilized for electromagnetic suppression (EMI) application.

Full Text

This paper investigates the potential of coconut shell powder (CSP) and coconut shell activated carbon (CSAC) with epoxy resin matrix composites to be used as absorbing materials over frequency of 1-8 GHz. Carbonaceous materials are preferable to be used as electromagnetic absorbent due to its excellent thermal conductivity. The CHNS Elemental Analysis is performed to evaluate the carbon composition (%) of the raw CSP and CSAC. From CHNS analysis, it was found that the carbon % of CSP and CSAC is 48.37% and 83.94% respectively. The surface porosities of CSP and CSAC were examined using scanning electron microscope (SEM) at an accelerating voltage of 15 kV. The porosity of CSP and CSAC is in the range of 2µm and 1µm respectively. The dielectric properties (complex permittivity) of the composites were determined by using high temperature dielectric probe in conjunction with Network Analyser. The dielectric constant for CSP and CSAC is 3.769 and 7.240 respectively while the dielectric loss factor for CSP and CSAC is 0.289 and 0.859 respectively.

Full Text

In the fabrication of MOSFET devices, the process parameters play a very important role in deciding the MOSFET device’s characteristics. The process parameter variations may contribute a significant impact on the dopant profiles that directly affect the device characteristics. These variations cause significant unpredictability in the power and performance characteristics of the device that may cause the degradation of the device performance. Therefore, a special technique involving design and analytical experiments is required to identify the process parameters that contribute the most of these variations In this current study, the L27 orthogonal array of Taguchi method was utilized to optimize the variability of process parameters on threshold voltage (VTH) in Ultrathin Pillar Vertical Double Gate MOSFET Device. This work was initially performed by using Silvaco technology computer-aided design (TCAD) simulator consisted of a process simulator (ATHENA) and a device simulator (ATLAS). These two simulators were combined with the L27 orthogonal array of Taguchi method in order to obtain the robust design recipe. The results revealed that the halo implant tilt was the most dominant process parameter that had the strongest effect on threshold voltage (VTH). Meanwhile, halo implant dose was selected as an adjustment factor in order to obtain the desired threshold voltage (VTH) value. The most optimum VTH value was observed to be 0.443 V and it is only 0.89% lower than the target or nominal value (0.447 V). This value is still within the predicted range of ITRS 2013 for low power (LP) multi-gate (MG) technology requirement in the year 2020.

Full Text

With the advancement in microfluidic technology, fluid flow control for syringe pump is always essential. Precise fluid flow in microfluidic device would able to perform emulsion and well-mixed fluid. In this paper, a mechatronic syringe pump has been developed and customized to control the high fluid flow in a poly-dimethylsiloxane (PDMS) microfluidic device based on a polyimide laminating film. The syringe pump was designed to drive continuous fluid in a polyimide based microfluidic device at flow rates of 1 - 5 ml/min. The electronic system consists of an Arduino microcontroller board and a uni-polar stepper motor. The program designed to control the rotation speed of the stepper motor was also discussed in this paper. As the motor rotates, the plunger pumps the liquid out of the syringe. The accuracy of the fluid flow rate was determined by adjusting the number of micro-step/revolution to drive the stepper motor to infuse fluid into the microfluidic device. The microfluidic device was made of polydimethylsiloxane to increase sealed convalently to the adhesive polyimide. With the precise control of the electronic system, the syringe pump could accurately inject fluid volume at 1- 5 ml/min into a microfluidic device.

Full Text

This paper presents an enhanced coupling peripheral type ring resonator which is study of coupling efficiency at feed lines of the sensor and between an empty quartz capillary. The proposed 2.4 GHz ring-resonator demonstrates significant change in resonance frequency and the insertion loss due to the different coupling gaps. Apart from that, a comparison among developed simulation models is performed in order to determine the effect of gap coupling dimensions.

Full Text

A new class of compact circular microstrip antenna with harmonic suppression for 2.45GHz is proposed. The purpose of harmonic suppression antenna is to eliminate additional insertion loss of filter used in rectenna circuit. This compact circular patch antenna has an advantage of excellent higher harmonic suppression. This characteristic is achieved by suitable introducing stub at the transmission feed line to suppress spurious radiation exhibit near third order effectively. Then, rejection characteristics have been improved using defective ground structure and slit. It is found that, the harmonic rejection technique applied improved the return loss level to -43.65dB at desired frequency with bandwidth around 122MHz. In addition, the antenna structure provides simple design with harmonic suppression capability. The single element of antenna harmonic suppression is design on FR4 substrate with relative permittivity, Er =4.7 and a thickness of 1.6mm offers a moderate gain 2.61dB and suppress the second and third harmonic up to -3dB. Thus, the proposed antenna harmonic suppression is recommended to be applied in rectenna and active integrated antenna applications, so that gives size reduction, inexpensive and efficient.

Full Text

This paper reviews of high efficiency CMOS class-E power amplifiers (PAs) in gigahertz (GHz) frequencies for wireless applications. The study is focused on the challenges in designing class-E PA especially in GHz frequencies. Problems and limitations in high efficiency class-E PA and the circuits’ topologies are reviewed. Several works on CMOS class-E PA from year 1999 to 2014 are discussed in this paper. Recent developments of CMOS class-E PAs are examined and a comparison of the performance criteria of various topologies is presented.

Full Text

Proton Exchange Membrane Fuel cell (PEMFC) generates electricity by electrochemical reaction of hydrogen gas and oxygen gas. Identification analysis is required to monitor the effect of fuel pressure towards the performance of PEMFC. Spectrogram capable to tracing changes in the phase behavior of electrical operations as external parameters is varied. Spectrogram is one of the time-frequency distribution (TFD) analysis techniques as it indicate a 3-Dimensional (3-D) graphic of the energy voltage with depend on frequency and time. The use of this technique is provided in this paper within the scope of monitoring the signal changes in the various load change of a 2000 Watt (W) PEM fuel cell stack. The 99.99% purity of hydrogen inlet pressure is varied from 0.1 bar to 0.5 bar using pressure regulator. GW-Instek GDS-3254 oscilloscope captured the waveform signal with various load demand between 0Amp until 36Amp (A) current. Thus, Spectrogram generated the monitoring of signal voltage and its parameter estimation of voltage direct current (VDC), voltage root means square (VRMS), and voltage alternating current (VAC) of every load changes on various pressure conditions. The voltage performance increases with rise in hydrogen inlet pressures and the spectrogram energy signal increases accordingly. The result shows that voltage performance of PEMFC increased as increased in hydrogen pressure. Therefore, the spectrogram technique has been proven useful and practical in identification parameter of various hydrogen inlet pressure of a PEM fuel cell stack.

Full Text

The autonomous underwater vehicle (AUV) mostly has fewer control inputs than the degree of freedoms (DOFs) in motion and be classified into underactuated system. It is difficult tasks to stabilize that system because of the highly nonlinear dynamic and model uncertainties. Hence, it usually required nonlinear control method and this paper presents the stabilization of an underactuated X4-AUV using integral backstepping control method. The X4-AUV system is executed by separating system into two parts subsystem which is translational and rotational subsystems. Integral backstepping control is applied for translational and rotational subsystem. The effectiveness of the proposed control technique for an underactuated X4-AUV demonstrates through simulation.

Full Text

This paper presents a design of double stage cascaded using band pass matching and L matching network using inductive and RC feedback. The design of the low noise amplifier implemented a Super-low noise InGaAs HEMT MGF4937AM transistor manufactured by Mitsubishi to operate with Ultra-wideband frequency which covers from 3.1 GHz to 10.6 GHz frequency band. The LNA is designed by using inductive drain feedback, RF feedback technique and band pass filter network as the input matching technique and L matching network as output matching using Advanced Design System software by Agilent. The LNA provides an input return loss (S11) which less than -10 dB and the gain (S21) more than 10 dB and noise figure less than 5 dB. Bandwidth achieves is more than 7 GHz and stability of the transistor managed to be more than 1.

Full Text

In this paper, the comparative studies of switchable bandstop to bandpass (or bandpass to bandstop) are presented. It shows that by using microstrip technology, high-Q bandstop to bandpass responses is difficult to achieve. Therefore, this paper proposes a new technique of matched bandstop to bandpass filter using two lossy low-Q resonators. The proposed technique is implemented based on perfectly-matched bandstop topology which is not only produced high-Q bandstop filter, but also easy to switch from bandstop to bandpass response. The PIN diodes (as switching element) that used in this proposed technique are incorporated into the topology to exhibit either matched bandstop response or bandpass response by turning “ON” and “OFF” of the PIN diodes. The proposed technique based on simulation result was carried out. As a result, it was found that the proposed technique was able to switch the microstrip filter from matched bandstop to bandpass filter using two lossy low-Q resonators.

Full Text

Orthogonal frequency division multiplexing system is considered one of the important technologies, which used in the high-speed wireless communication system. Although, it has many advantages such as high data rate, ability to combat the multipath fading channels and more efficiency for utilization the bandwidth, the same time has some obstacles also. The peak to average power ratio considers the major drawback of OFDM system. In the OFDM system, some instantaneous power outputs increase greatly and become so far greater than the mean power of the system with the condition the phases of these carriers are same, this is defined the high PAPR, which causes running the system devices in the nonlinear region leading deterioration in performance of OFDM system. In this paper, we present the characteristics of PAPR with two cases normal and special cases (when the OFDM signal has large consistency samples). At the same time, the parameters that influence to PAPR performance have been analyzed and simulated by using MATLAB software. The simulation results show the numbers of sub-carriers, modulation schemes and over sampling rate influence to PAPR performance. It is observed that the numbers of sub-carrier have the significant influence on PAPR performance. However, over sampling rate and modulation schemes have a small effect on PAPR performance.

Full Text

Nowadays, the ever-growing demand for mobile communications is constantly increasing the need for improved capacity, better coverage, and higher-quality service. Whereas three major disabilities limit the capacity and reliability of wireless communication systems; multipath fading, delay spread, and co-channel interference. Beamforming (BF) technique is a powerful means of increasing capacity, data rates and coverage of the wireless cellular communication system. One of the common and widely used approaches to Adaptive Beamforming (ABF) is the Minimum Variance Distortionless Response (MVDR) which can reduce the interference plus noise power without distorting the desired signal. In this paper, MVDR BF with various antenna array geometries includes; uniform linear arrays (ULAs), uniform rectangular arrays (URAs) and uniform circular arrays (UCAs) each consisting of L elements operated in frequency of 2.6 GHz that is implemented in LTE networks were used for analyze and compare the performance of MVDR beamformer. From this study, it is found that the MVDR BF technique with ULA has the best performance and capable of forming adaptive beams with nulling capability towards interfering signals of average null power up to 42.8 dB with improvement on SINR approximately 9% and 11% comparing to UCA. As comparisons, the MVDR technique with ULA is much more accurate than the URA and UCA to null the interference source and steer its radiation lobe with high power towards the desired signal. To evaluate the performance of this work one user with four interferences sources were used through computer simulation by using Matlab.

Full Text

A compact triple-band meander line antenna for global system for mobile communication (GSM), distributed control system (DCS) and universal mobile telecommunications system (UMTS) applications operating at the frequencies band of 0.9 GHz, 1.8 GHz and 2.1 GHz is designed. Most demanded wireless communication bands are covered in this design for consumer electronics. The resonant frequencies are 0.9 GHz with the return loss of -21.262 dB and the corresponding radiation pattern with maximum gain of 2.09 dBi, 1.8 GHz with the return loss of -19.011 dB and the corresponding radiation pattern with maximum gain of 2.32 dBi, and 2.1 GHz with the return loss of -20.203 dB and the corresponding radiation pattern with maximum gain of 3.7 dBi. The antenna was printed on a FR4 substrate with dielectric constant of 4.7. The simulated result was verified through measurement in which a good agreement between the simulated and measured result was documented. An application example is shown for the proposed design which is an integrated system to detect the level of electromagnetic field radiation at GSM frequencies.

Full Text

A comparison between rectangular microstrip patch and C-shaped patch antennas are proposed in this paper for wireless local area networks (WLANs) applications operating at the frequency band of 5.2 GHz. The rectangular patch antenna has a return loss of -40.951 dB and bandwidth of 7.9% at 5.2 GHz. The patch antenna has an Omni-directional radiation pattern with maximum gain of 6.5 dBi. The C-shaped patch antenna has shown a bandwidth improvement of more than 13% at a return loss of -43.859 dB better than -10 dB. Similarly, the C-shaped antenna has shown a size reduction of more than 16% compared to the rectangular microstrip patch antenna. However, the antenna’s radiation pattern is more to unidirectional pattern with reduced gain of 4.830 dBi compared to the rectangular microstrip patch antenna. Both antennas were printed on a FR4 substrate with dielectric constant of 4.7. The simulated results were verified through measurement in which a good agreement between the simulated and measured result were documented.

Full Text

Promoting the use of Renewable Energy (RE) resources has become one of the top government agendas throughout the world. However, in order to develop RE such as Concentrating Solar Power (CSP) in Malaysia, several key factors that affect the performance of this system should be thoroughly investigated. Therefore, this paper aims to study the feasibility of implementing Parabolic Dish (PD) based on CSP in Malaysia environment by evaluating the CSP technologies, Meteorological data, Direct Solar Irradiance (DNI), global Parabolic Dish development, sites selection, and Levelized Cost of Energy (LCOE) of the PD system. Therefore, an innovative development and research of Parabolic Dish CSP should be carried out with an in depth consideration on both technical and economic aspects to ensure that the Parabolic Dish technology development will be as matured as the other CSP technologies.

Full Text

In this paper, a new type of microwave sensor for determining and detecting the dielectric properties in common solid such as meat is proposed. Various resonators such as coaxial cavity, dielectric, and waveguide resonators have been used for material characterization. However, these resonators are often large in size, expensive, and they have low sensitivity with poor Q-factor. Thus, a new planar resonator technique is presented in order to have higher Q-factor. This type of sensor is based on perturbation theory, in which the dielectric properties of the resonator effect the quality factor and resonance frequency of the microwave resonator. A microstrip of symmetrical split ring resonator (SSRR), which has two gaps, is adopted for the design of the sensor. This resonator is suitable for various industry applications such as food industry, quality control, bio –sensing medicine and pharmacy. A very good agreement is illustrated between the calculated and simulated results at operating frequency of 2.2 GHz. In addition, a high sensitivity is achieved in the same operating resonance frequency by using High Frequency Structure Simulator (HFSS).

Full Text

In this paper, a new modified multi-input boost converter is proposed using H-bridge cells as building blocks and uncoupled inductors in parallel using interleaved technique as ripple reduction method. The objectives of this paper are to design a high ripple reduction and a high-performance multi-input boost converter. Different operating modes and the switch realization of the new converter are obtained. The modes of operation based on the status of the four switches. The proposed multi-input boost converter is composed of two inputs source that accommodated with some extra semiconductors, inductances and diodes to form the interleaving technique as proposed method. The proposed concept has been investigated through simulation using the MATLAB/Simulink environment. The simulation results confirm the validity of the proposed method, which can be seen as a promising new topology that ensure multi-input converter suitable for renewable energy applications.

Full Text

This paper briefly reviews the feasibility of using multispectral imaging approach to noninvasively determine one's mean blood oxygen saturation, SmO2. We described the use of Extended Modified Lambert Beer (EMLB) model and a nonlinear fitting algorithm to quantitatively analyse the measured spectroscopic data over a wavelength range of 520-600 nm to give the best estimation of SmO2. The experimental work required spectroscopic images to be collected from the right index finger of four recruited volunteers at resting condition and after a pressure of 140 mmHg is applied on their upper right arm. The obtained results revealed a percent SmO2 of 77.5 ± 1.06% at resting condition and 54.3 ± 0.42% during blood flow occlusion. These results are also compared to that reported in previous works. The results show that these ranges and the drop in the mean percent SmO2 obtained for at rest compared to blood flow occlusion condition agreed considerably well with that reported in the literature. This work concluded that the developed multispectral imaging system could potentially be used as an alternative means to noninvasive monitoring and detection of changes in one's mean blood oxygen saturation with external interventions.

Full Text

With the advent of portable and high-density microelectronic devices, the power dissipation of very large scale integrated (VLSI) circuits is becoming a critical concern. In this paper, three low power CMOS digital design techniques have been compared in terms of their speed, power consumption and area. For comparison purposes, 1-bit full adder circuits are constructed based on each of the design technique in 0.35 µm CMOS technology using Mentor Graphics tools.

Full Text

This paper proposed an approach of Fuzzy-Extended Kalman Filter (FEKF) for mobile robot localization and mapping considering unknown noise characteristics. The techniques apply the information extracted from EKF measurement innovation to derive the best output for mobile robot estimation during its observations. This information is then fuzzified using Fuzzy Logic technique, designed with very few design rules to control the information. The method can further reduced measurement error and as a result provides better localization and mapping. Simulation results are also presented to describe the efficiency of the proposed method in comparison with the normal EKF estimation. Preliminary results emphasize that FEKF has exceeds the estimation results performance of normal EKF in non-Gaussian noise environment.

Full Text

Building a sport robot that can defeat human players in sport activities is the aim of many researchers and engineers in robotic related fields. This paper presents a design of a mobile badminton robot that can serve a shuttlecock as a human player in a standard badminton court. A transporting shuttlecock system was designed to preload six shuttlecocks. A serving mechanism was designed to swing a standard badminton racquet to hit a dropping shuttlecock timely. The challenges and the proposed solutions that involved during the development of the shuttlecock serving system and serving mechanism are discussed. Findings indicate that the proposed design is able to preload and serve six shuttlecocks continuously with a success serving rate of 89% in a standard badminton court when the time between swinging the racquet and dropping a shuttlecock was optimized.

Full Text

Energy storage systems become crucial when power generated from power plant does not fulfill peak power load demand. Due to that reason, technologies such as rechargeable battery are beneficial options for energy storage system. The accurate data information about the battery parameter is important, to maintain the battery in a state in which it can fulfill the functional requirements of the application for which it was specified. This paper presents the application of spectrogram in battery signal analysis for Nickel-Cadmium (Ni-Cd). This paper focuses on the analysis of Ni-Cd battery with nominal battery voltage of 6 and 12V with the storage capacity from 5 to 50Ah, respectively. The signals from battery charging and discharging were then analyzed using MATLAB/SIMULINK to obtain the time-frequency representation (TFR). Based on the TFR, the estimation parameters such as instantaneous RMS voltage, instantaneous voltage direct current (VDC) and instantaneous voltage alternating current (VAC) were obtained to visualize the trend of battery signal performance. This study found that the nominal voltage and storage capacity for battery can be estimated through the VAC parameter.

Full Text

This study reviews the contemporary tendencies in energy efficiency performance in chosen regions and countries. It also reviews the energy efficiency strategies and activities accomplished in these countries which pursue the program of reduction in energy consumption while maintaining the comfort level. These become the objectives and today’s energy efficiency requirement. This study also aims to highlight these activities and the outcomes of the energy efficiency implementation. The extent of this action and its effectiveness is being ascertained. The indicator used to evaluate the Energy Efficiency activities is the Energy Intensity Indicator which is provided by International Energy Agency (IEA). The reports and measurements of the International Energy Agency (IEA) are considered in order to make comparison among the selected countries. The main reason of focus on Energy Intensity levels is because this indicator reflects the result of all activities in different sectors and make sense which country has fulfilled the requirement of Energy Efficiency. The regions and countries are selected on the basis that their level of achievement in the energy efficiency programs are high. However, comparison is still made because each region and country has different emphasis and focus. Despite that Malaysia is a developing country, the achievement towards satisfactory energy efficiency implementation can be considered as encouraging and can only advance further if energy efficiency practice in these selected countries will be learned.

Full Text

Distribution system is a part of electrical system that suffering from a number of problems, such as load variation, voltage fluctuation, and harmonic distortion. Harmonic distortion is one of the concerns recently taking more attention since it may cause losses amplification, rms voltage increment, and, the most dangerous effect is, equipment destruction if resonance frequency occurs. The extensive use of devices generating harmonic frequencies is the main reason of the problem. The nonlinear v-i characteristic of the devices may result in distortion of system voltage that should be prevented not to spread and further deteriorate the system. For this purpose, harmonic filter is commonly installed in the system. Distribution system normally includes a number of shunt capacitors for voltage improvement and losses minimization. However, the capacitors may also amplify the distortion. In this paper, the location and size of harmonic filters is determined using Genetic Algorithm. The aims are to improve the voltage and minimize the losses while mitigating the distortion. The implementation on the IEEE 18-bus system indicates simultaneous system enhancements including voltage improvement, losses reduction, and harmonic mitigation with minimum system modification and cost requirement.

Full Text

Passive Compact Molten Salt Reactor (PCMSR) is an advanced nuclear reactor designed to utilize thorium as the main fertile fuel to achieve sustainable long term natural nuclear fuel resources utilization. Thorium (i.e. 232Th) will be converted to 233U and finally 233U undergoes neutron induced fission reaction and generates reactor thermal power. Because U-233 does not exist at initial fuel, the other fissile fuel is needed for initial operation of PCMSR. To avoid illicit use of high grade fissile materials, the low enrich uranium (LEU) is used for the initial fissile fuel. During several years of the initial reactor operation, 235U at LEU will be depleted and 233U will be produced and also be consumed. To maintain reactor criticality, the production of 233U must balance the consumption of 233U and the depletion of 235U. For long term operation, the reactor must be able to maintain its criticality by solely the balance of 233U production and 233U consumption. This paper explains the numerical study results of the ability of the PCMSR to maintain its fuel composition. The PCMSR in this study uses the initial fuel with the composition of 6.3 % mole (LEU)F4, 23.7 % mole of 232ThF4 and 70 mole % of 7LiF. The enrichment level of LEU is 19 % mole of 235U. The nuclide composition of the PCMSR fuel will be analyzed by solving the simultaneous ordinary differential equations of nuclide balances. There are 38 nuclides involved in this analysis including uranium isotopes, plutonium isotopes, minor actinides (Np, Am, Cm), thorium, protactinium and six neutron poison fission product nuclides. The calculations are performed for several values of specific power i.e.: 9 MWth/(ton HM), 18 MWth/(ton HM), 27 MWth/(ton HM), 36 MWth/(ton HM) and 44 MWth/(ton HM). The fuel extraction rate is assumed to be proportional to the specific power values, i.e 931 (cm3/day)/(MWth/(ton HM)). The specific thorium injection rate is 828 kg/GWey. The calculation results show that the PCMSR fuel can achieve quasi equilibrium fuel composition for long term operation (i.e. 100 years). In this condition, the total fissile mole fraction (i.e. the sum of mole fractions of 233U and 235U related to total heavy metal mole) can be maintained to almost constant value (i.e. at the range of 2.600 to 2.759). However during the early years of its operation, there is a depression of the value of total fissile mole fraction. The depression becomes more prominent as the value of specific power increases. The minimum fissile mole fraction is 2.477 for the specific power of 9 MWth/(ton HM), 2.430 for 18 MWth/(ton HM), 2.365 for 27 MWth/(ton HM), 2.304 for 36 MWth/(ton HM), 2.237 for 44 MWth/(ton HM). This depression is due to the delay time of the production of 233U after the neutron capture of 232Th. Based on these calculations, a low specific power is recommended. The calculation results can be summarized that for long term operation, PCMSR fuel can maintain total fissile mole fraction at quasi equilibrium condition. A depression of total fissile mole fraction value occurs during the early years of PCMSR fuel operation, which becomes more prominent as the increasing value specific power.

Full Text

The LiFe0.9Ni0.1PO4 was developed from active cathode material LiFePO4 for Lithium ion Battery. Ni doping was used to increase lithium ion diffusion. This active material of LiFePO4 has low conductivity approximately 10-9 S/cm. By having carbon coated on the surface of LiFe0.9Ni0.1PO4 powder, the conductivity characteristic is expected to increase. Cassava powders, tapioca, as carbon sources were mixed and milled for 3 days with ball mill method. The process varied on the weight ratio between tapioca and LiFe0.9Ni0.1PO4, which were 1:4; 1:5 and 1:6. The next step in mixed millings product was heating with pyrolisis method at a temperature of 8000C and under gaseous nitrogen flow. From the XRD analysis, it is shown that the coated carbon is in a form of amorphous phase. Atomic Ni was well detected by using mapping mix SEM. The coating of carbon of the sample with weight ratio of 1:5 had sufficient carbon on its surface and a conductivity of 4.4 10-3 S/cm.

Full Text

A white rice husk ash with a silica content of more than 99% was produced from a rice husk by a citric acid treatment before heating the rice husk at 700 °C to 1000 °C. The white ash mostly consisted of an amorphous phase, and cristobalite usually found after heating rice husk was not detected. The amorphous phase was still formed although the rice husk was burned at 1000 °C. These indicated that the citric acid dissolved part of the carbon compounds in the rice husk, followed by releasing of potassium and other alkali cations, and as a result, an amorphous high silica ash was formed without incorporation of crystal phases such as cristobalite. The white rice husk ash was successfully converted into ZSM-5, a zeolite widely used as a catalyst in the petroleum industries.

Full Text

Focus of solar cell industry is to reduce production cost as much as possible while maintaining solar cell performance at a desirable level. The largest share of solar cell production cost comes from wafer price. Currently wafer-based solar cell uses about 300 µm wafer thickness for its daily production. It is therefore very important to reduce wafer thickness as part of effort to reduce production cost of solar cell. This research is focused to examine the effect of bulk doping level and wafer thickness reduction on the performance of wafer-based silicon solar cell. Research was performed by simulating the effect of bulk doping level and wafer thickness on the output parameters of solar cell. Optimation was done on phosphor emitter doping level of 7.50×1018/cm3, junction depth of 1.56 um, cell surface area of 1 cm2 and illuminated under AM1.5G spectrum with the intensity of 100 MW/cm2.Simulation result showed that solar cell with efficiency between 18.15-18.7% was achieved by using wafer thickness between 300 and 320 um and boron doping level (bulk doping level) between 1.84x1017 – 2.68x1017/cm3. On this condition solar cell had short circuit current density, JSC of 0.32 A/cm2, open circuit voltage, VOC of 0.70 V, maximum output power, PMAX of 0.0182 W/cm2, and fill factor, FF of 0.829.

Full Text

The development of electronics industry in keeping the chip size to be smaller has challenged its thermal management to maintain the maximum chip temperature below 80 °C. The correlation as a method to estimate chip temperature, when only the chip’s heat rate or power input and inlet coolant temperature are known, is obtained. The equations involving pressure drop, pool boiling and film condensation characteristics that explain the heat transfer process and flow phenomenon inside the thermosyphon flow are derived to obtain the correlation. A new design of a two-phase thermosyphon water-cooled condenser system as the electronic cooling system has been built to acquire the experimental data. This thermosyphon design uses R-113 as working fluid and water as external coolant condenser (flows through the cooling coil). The condensation occurs as film condensation at the outer of radial water coolant coil. The R-113 liquid condensate will then return back to the evaporator section through the downcomer section by gravity rather than by capillary forces. The thermosyphon system (excluding the water coolant coil section) is thus a passive system, and its evaporator section must be located below the condenser. In the present work, the heat supply component is simulated by a cartridge heater. This cartridge heater is in direct contact with the working fluid. The water coolant condenser is supplied by solution bath. Furthermore, the evaporator, riser, condenser, and downcomer are well insulated and all applied heat is assumed to be transferred through the thermosyphon. In the experiment, the varying mass flow rate and voltage at a constant inlet water temperature ( ) of 10ºC, 15ºC and 20ºC were measured. The correlation obtained as function of heat flux and temperature difference between chip and coolant inlet temperature is valid as they are in good agreement with the experimental results.

Full Text

The Uranium Concentrate Production Installation (UCPI) operation generates sludge radioactive waste containing uranium that must be immobilized by solidification process for preparation of disposal to ensure the environment safety in the present and future. This research aims to immobilize the radioactive sludge waste by solidification using coal fly-ash (CFA) as matrix material of supercalcine silico-titanate synroc compared to supercalcine zirconio-titanate synroc (standard synroc). The immobilization process was carried-out by mixing the radioactive sludge waste with CFA and precursor oxides namely BaO, CaO, and TiO2 as addition of matrix materials. The matrix material composition of synroc using CFA (in weight %) i.e : Al2O3 (6.26); BaO (5.33); CaO (10.52); TiO2 (68.02) ; and SiO2 (6.07). The matrix material also contains oxides minor i.e : Fe2O3 (3.48), MnO2 (0.04), K2O (0.20) and Na2O (0.08). Waste loading in the waste synroc block was 30 weight %. The mixture was dried at temperature of 100 oC, and calcined at 750 oC. The calcination powder resulted was pressed in the mold. Furthermore, the sintering process was carried-out at the temperature of 900 – 1300 o C for 1-4 hours to form the synroc block of solid multiphases ceramics. A comparison of immobilization process was done using matrix material of supercalcine zirconio-titanate synroc. The synroc block quality produced from immobilization was determined by testing density, compressive strength, and leach-rate of uranium. The test results showed that the best quality of waste supercalcine silico-titanate synroc block was obtained at the sintering temperature of 1100 oC for 3.5 hours with density 2.29 g/cm3, compressive strength 5.76 kN/cm2, and leach-rate of uranium 1.05x10-6 g.cm-2.day-1. Whereas the immobilization process using the standard synroc obtained the optimum sintering condition at 1200 °C for 3 hours, with density 2.85 g/cm3, compressive strength 10.98 kN/cm2, and leach-rate of uranium 1.17x10-5 g.cm-2.day-1. The quality of both synrocs by this sintering process conform with the quality of synroc block by the hot isostatic pressing process, and fullfill the quality recommended by the IAEA. By comparing the characteristic test results and economic aspects of both waste synroc blocks, the supercalcine silico-titanate synroc matrix using CFA can be utilized as alternative to replace the matrix material of standard synroc for immobilizing sludge radioactive waste containing uranium.

Full Text

Output performance of crystalline (poly-Si) and thin film (a-Si/µc-Si) photovoltaic (PV) array has been evaluated in the area of PUSPIPTEK-Serpong for a period of seven months. The output power of both types of PV array at STC conditions is 1.0 kWp and 0.88 kWp, respectively. Each type of PV array is equipped with 2,5 kW grid-type inverter. The aim of this research is to determine the amount of energy produced by both types of solar cells at outdoor conditions. The performance ratio (PR) and the module yield (Ym) have been used to examine the performances of both PV modules. The electrical outputs of the PV array such as, current, voltage, maximum power, and the environmental parameters such as light intensity, PV cell’s temperature, ambient temperature, and wind speed were measured automatically by a data logger for every 5 minutes. For the data calculations, the output power of both PV array were normalized to their output power at the standard test conditions (STC). The electrical parameters output (I-Vcurve) of both PV modules measured by the Sun Simulator were used as based for the data calculation. Results from the analysis of seven months data accumulated at outdoor conditions shown that the performance ratio (PR) for a-Si/µc-Si PV module was about 10% greater than the Poly-Si module. The average value of module yield Ym for Poly-Si was about 32% for Poly-Si, and 36% for a-Si/µc-Si, respectively. The difference of Ym of both PV modules was approximately 3.1% for a-Si/µc-Si. This result indicated that the PV array of a-Si/µc-Si produced energy of about 3.1% greater than poly-Si on the conditions in Serpong.

Full Text

The Supervisory Control And Data Acquisition (SCADA) System for the Bersia Group Control Centre (BGCC) is an essential tool in the operation of Sungai Perak Power Stations (SGPS) hydroelectric power plants. It control and monitors remotely the daily operations of all hydroelectric power plants in the SGPS scheme which consist of seven generating facilities with a combined generating capacity of 1,248 Megawatts (MW), being among the major assets to Tenaga Nasional Berhad (TNB) Generation. All the hydro plants in the SGPS scheme are remotely operated with minimal interruption to its SCADA functions. The existing SCADA system in operation since 1998 has enable SGPS personnel to manage and operate the remote hydro plants efficiently, productively and safely. However, it has come to the end of its electronic life span. Thus, the modernization of SCADA System for SGPS been proposed and will be executed in 2016.

Full Text

Gas diffusion layer (GDL) plays an important role in polymer electrolyte membrane fuel cell (PEMFC). It provides diffusion media that transport reactant gas into catalyst layer, mechanical support for electrolyte membrane, electrical pathways for electron, and serves channel product water away from the electrode. In this study, the main physical properties (hydrophobicity, electrical conductivity, and porosity) and the performance of GDL made from activated carbon powder from coconut coir were investigated. Its properties were also compared to commercially available GDL, Toray TGP-H-120 (TGP-120). Gas diffusion layer coconut carbon paper (CCP) was fabricated by mixing the coconut carbon powder, ethylene vinyl acetate, polyethylene glycol, and xylene using hot plate stirrer at 100?C. The carbon slurry was casted to make carbon paper and then dried at room temperature. The carbon paper was also treated with PTFE solution to improve its hydrophobicity. SEM images showed that CCP had smoother surface morphology and denser compared to TGP-120, however, its porosity was quite similar, 69% and 74%, respectively. This was estimated because CCP had internal porous on the surface of coconut fibres. Although low conductivity of CCP still needed a further improvement, its relatively high hydrophobicity would be benefited the water management inside the cell. By measuring the cell performance in a single cell proton exchange membrane fuel cell (PEMFC) with an active area of 25 cm2 using H2/O2 reactants, CCP showed a good fuel cell performance with current density of about 232 mA/cm2 at 0.6 volt, compared to 284 mA/cm2 for TGP-120. Power peaks were revealed at 168 and 208 mW/cm2 for both CCP and TGP-120, respectively.

Full Text

Calophyllum inophyllum oil is a non-edible oil, which the plant is widely available in Indonesia, with a very high free fatty acid content of around 30% or acid value of 60 mg KOH•g-1. Two-step transesterification comprised hydrochloric acid-catalyzed esterification and sodium hydroxide-catalyzed transesterifications was conducted in batch processes. The first step esterification was carried out with molar ratio of methanol to oil of 35:1, hydrochloric acid concentration of 15 wt.%, and stirring speed of 500 rpm for 3 h reaction time at 60°C. This esterification reduced the acid value of Calophyllum inophyllum oil from (59.97 ? 2.71) mg KOH•g-1 to (5.33 ? 0.71) mg KOH•g-1. In second step transesterification, response surface methodology, a central composite design, was utilized to optimize reaction conditions which maximized biodiesel yield and minimized acid value. The optimum conditions included molar ratio of methanol to oil of 11.95, sodium hydroxide concentration of 1.26 wt.% for 1.52 h reaction time at 50?C were established. At these optimum conditions, the maximum biodiesel yield of (84.90 ? 0.31) % and minimum acid value of (0.303 ? 0.015) mg KOH•g-1 were achieved which were comparable with predicted values. The second step of transesterification was the second-order reaction with reaction rate constant of 0.047 to 0.180 (M-1•min-1) at 30 to 50?C. The activation energy of 54.53 kJ•mol-1 was obtained.

Full Text

Isolation condenser (IC) is considered as an important equipment for especially severe accident management because IC has the ability to cool reactor core without power source. In order to evaluate heat transfer performance of IC accurately, experiments for the detailed performance evaluation in two-phase flow in a condenser are required. Thus, completion position of condensation in heat tube of a condenser is important to calculate heat transfer area of steam portion in heat tube. Experimental apparatus was fabricated for evaluation of heat transfer performance inside heat tube which simulated IC. Heat tube of test section was U-shaped horizontal tube and is installed in condensation tank with coolant water. In this study, temperature distribution in the heat tube was measured to estimate completion position of condensation. The experiment was carried out with changing steam flow rate and steam pressure. As a result, movement of completion position of condensation was suggested with increasing steam flow rate and maintaining temperature distribution of the coolant water. Therefore, availability of this method is validated.

Full Text

Universitas Gadjah Mada (UGM) is aiming to be a university that leads dissemination of application of energy conservation principles with its Green Campus concept. One of Green Campus concepts is the green behaviour by giving information and inviting citizens to use energy, water and paper efficiently and giving education to citizens about environmental issues. One of the examples in energy efficiency practice is car-free streets. Energy consumption can be shown by number of vehicles and number of vehicles can be shown by sound level comparison or sound level mapping. Sound level mapping is a graphic representation of the sound level distribution existing in a given region, for a defined period. The higher sound level indicates more vehicle pass through an area. Number of vehicles and limited street capacities create traffic jam frequently. During a traffic jam, vehicle burn fuel but not moving and cause bad effect to environment. Sound level mapping is needed to know how big the effect of sound level to environment quality. Optimizing environment quality can be made by giving suitable recommendation based on sound level mapping. In this research, sound level mapping is conducted using Geographic Information System (GIS). GIS integrates five key components: hardware, software, data, people and methods. Universitas Gadjah Mada is selected as the research location due to the large amount of vehicles used by students and the areas intersect with public spaces. Data were collected in five areas which have intersections with public spaces such as hospital, shopping center, worship place, food court, and main road. Measurement points will be given for each area. Sound level data is processed using signal processing software, Adobe Audition CS6, then processed using mapping software, Surfer 11.0. This sound level mapping linked with traffic volume data for each street in UGM. Based on sound level mapping, maximum percentage of white acoustic zone for each area is only 18%. Meanwhile, most of the areas are black acoustic zone with sound level over 65 dB (A).

Full Text

The aim of this study is to investigate the effect of EGR and wet methanol as the fuel blends on the performance and emission of EFI gasoline engine. The content of wet methanol blended with the gasoline fuel was 5 to 15% by volume. EGR rate was 7.25% by volume of mass inducted into the combustion chamber. Engine speeds were varied in the range of 2500 to 4000 rpm with 500 intervals for constant load of 25% from the maximum achievable load. By comparing the engine equipped by the EGR and without EGR system at the constant engine speed of 4000 rpm, a brake torque increases up to 12.9% for the case of engine fueled by pure gasoline fuel, while it increases up to 10.2% for the engine fueled by 15% wet methanol blend. At the same condition, BSFC decreases approximately 16.6% for the engine fueled by pure gasoline fuel, whilst it decreases up to 15.2% for the engine fueled by 15% wet methanol blend. The increase of brake torque and reduction of BSFC for engine equipped with the EGR system impacts on an engine brake thermal efficiency. The result shows that the brake thermal efficiency increases approximately 19.9% for the engine using EGR system compared with the engine without EGR system at the engine speed of 4000 rpm fueled by neat gasoline fuel, whereas it increases up to 18% fueled by 15% wet methanol blend. The use of EGR system, however, impacts adversely to the exhaust gas emissions produced by the engine. By comparing the engine equipped with the EGR and without using EGR system at the constant engine speed of 4000 rpm, CO emission increases approximately 94.7% for the engine fueled by neat gasoline fuel and up to 50% for the engine fueled by 15% wet methanol blend. At the same condition, the work indicates HC emission increases up to 50.7% and 78.6% for the engine fueled by pure gasoline fuel and 15% wet methanol blend, respectively. The brake torque increases small up to 2.9% and 0.4% for the engine fueled by 15% wet methanol compared with that of engine fueled by the neat gasoline fuel without and with EGR systems, respectively, at the constant engine speed of 4000 rpm. At the same condition, CO emission decreases approximately 73.7% and 79.7%, whilst HC decreases approximately 44% and 33.6%, respectively.

Full Text

An optimum fuel composition is a very important parameter in the operation of a pebble bed high temperature gas-cooled reactor (HTGR). In the present scoping study, the optimum ranges of heavy metal (HM) loading per pebble and the uranium enrichment are investigated. The HM loading range covers 4 to 10 g per pebble, while the uranium enrichment covers 5 to 20 w/o. Two fuel loading schemes typical to pebble-bed HTGRs are also investigated, i.e. the OTTO and multi-pass schemes. All calculations are carried out using BATAN-MPASS, a general in-core fuel management code dedicated for pebble-bed type HTGRs. The reference reactor design case is adopted from the German 200 MWth HTR-Module but with core height of half of the original design. Other design parameters follow the original HTR-Module design. The results of the scoping study show that, for both once-through-then-out (OTTO) and multi-pass fueling schemes, the optimal HM loading per pebble is around 7 g HM/ball. Increasing the uranium enrichment minimizes the fissile loading however higher enrichment than 15 w/o is not effective anymore. The multi-pass fueling scheme shows lower fissile loading requirement and a significantly lower axial power peaking than the OTTO scheme. It can be concluded that the optimum range of HM loading and uranium enrichment are found to be around 7 g per pebble and 15 w/o. In addition the multi-pass fueling scheme shows superior BURNUP and safety characteristics than the OTTO fueling scheme.

Full Text

Concentrated solar power (CSP) utilizes solar thermal energy for electric power generation by concentrating the solar radiation with mirrors. The existing solar concentration systems, such as parabolic trough, linear fresnel and tower, have problems of lower concentration efficiency in winter season and high latitude region. Cross linear concentrated solar power (CL-CSP) has been developed to achieve high concentration efficiency even in such conditions. Linear receiver line lies on east-west axis and mirror lines on north-south axis, therefore the both lines are crossed each other at right angles. Since mirrors of CL-heliostat are controlled with dual axes (rotation and elevation) for sun-tracking, high concentration efficiency can be obtained. In order to establish cost competitive and efficient CSP plant, feasibility study on 20 MWe CL-CSP was carried out using computer simulation. Pebbles and air are applied as thermal storage material and working fluid respectively considering the cost competitive system. Heat capacity of the thermal storage tank and the amount of solar concentration were assumed by the estimation of the energy balance of plant operation. The layout of the heliostat field of 20 MWe CL-CSP plant was designed and conversion efficiency from concentrated solar energy to electric power was estimated. High temperature of 600°C and the conversion efficiency of 24% (recovered heat to electricity) and 19% (electricity from concentrated solar energy) were obtained. Configuration design of thermal storage tank was also conducted. Finally the installation cost of the CL-plant was estimated to be compared with the conventional CSP-plant. The result shows the cost competitiveness of the CL-plant.

Full Text

Crop planning problem is a multi-objective optimization problem. It is related to many factors such as land type, capital, demand etc. From very earlier years, people have been trying to find out a best solution for crop planning to get more profit in exchange of less investment and cost. In this paper, we formulate a crop planning problem as a multi-objective optimization model and try to solve two different versions of the problem using two different optimization algorithms MCA and NSGA. In this two algorithms, they provide superior solutions to maximize total net benefit and minimize total cost. We investigate these algorithms here as a linear crop planning model and use them to acquire the maximum total gross margin according with minimum total working capital in order to satisfy some constraints. We also compare the performance of these two algorithms and analyse the solution from the decision-making point of view.

Full Text

Air Gap Membrane distillation (AGMD) is a prominent technology in the field of water treatment and desalination which is facing a lot of challenges to efficiently produce pure water supply. The system works under the principle of partial pressure difference created between a hydrophobic membrane and a coolant plate by varying temperature on both sides. The membrane and the coolant plate are separated by a thin air gap. Impure hot water flows over the membrane and the evaporated vapour is allowed to pass through the hydrophobic membrane only. Later this vapour condensed on the coolant plate and the pre distilled water is collected. Among the various factors affecting the performance of AGMD system, width of the air gap is the major one to consider. The target of this article is to understand the effect of air gap in AGMD system which will help to build an efficient AGMD water supply system in future using appropriate air gap. In this paper, heat and mass transfer process through the air gap has been discussed for AGMD and a numerical investigation was performed using ANSYS Fluent 15.0 software package and compared with previous experimental results. The investigation shows that distillate flux increased with the decrease of air gap width where the highest 96% of increase of distillate flux found when the air gap is decreased 2.5mm.

Full Text

River water contains both dissolved and suspended particles. Coagulation and flocculation processes are used to separate the suspended solids from the water. Conventionally, suspended solids and turbidity are removed from raw water by various chemical coagulants but most of them are costly and non-ecofriendly. Whereas, the bioflocculants are environment-friendly and could be used as coagulants. In general, bioflocculants cause aggregation of particles and cells by bridging and charge neutralizing. Most of the solids suspended in water possess negative charges and repel each other, for which they do not settle in the water body. This present study attempted to reduce turbidity of river water and kaolin suspension using fungal coagulants in Jar apparatus. Bioflocculant producing filamentous fungi were isolated from river water. Six strains showed good flocculating performance. Among them, supernatant of RWF-05 and RWF-06 showed turbidity removal of 95% and 75% from kaolin suspension, respectively. However, the removal of turbidity from river water was rather low with 23% and 22%, respectively. Dried biomass of RWF-03 showed a good flocculating rate of 80% after 24h settling time to kaolin suspension. The results showed that the clay particles of river water and kaolin were flocculated by the fungal supernatant and dried biomass and, as a result, they reduced the turbidity of river water.

Full Text

Object segmentation from single background colour image is important for motion analysis, object tracking, trajectory identification, and human gait analysis. It is a challenging job to extract an object from single background colour image because of the variations of colours and light intensity. Most common solution of the task is the uses of threshold strategy based on trial and error method. As the method is not automated, it is time consuming and sometimes a single threshold value does not work for a series of image frames of video data. In solving this issue, this paper presents an Automated Threshold Detection Algorithm, H(). The algorithm is applied in segmenting human lower limbs from a series of image frames of human walking. The procedure starts with selection of optimal RGB channel. Then H() algorithm is applied for automated threshold detection to convert the image frames into grayscale image. In the next stage, Line Fill (LF) algorithm is applied for smoothing the edges of object and finally background is subtracted to extract the targeted object. Results of the applied procedure show that the algorithm is viable to extract object from single background color image and can be used in human gait analysis.

Full Text

Marker-based 2D temporospatial image modelling is a common strategy in characterizing human gait where Channel filtering, Threshold imaging, and Line feel algorithm are normally used in foreground segmentation targeting human lower limbs of a particular image frame. This paper presents Temporospatial Image Modelling approach in presenting segmented objects with spatiotemporal view by reflecting various poses of lower limbs for forward walking. Lower limbs joint movement characteristics and angle variations are also presented in this paper where pre-assigned marker-points are modelled in tracking the motion trajectories. Results show various patterns of motion trajectories and angle variations for Hip, Knee, Ankle, Heel, and Toe of lower limbs through observing the variations of times, locations, and spatiotemporal representations. The results also characterize that the Swing and Stance phases of a gait cycle are about 40% and 60% of a gait cycle respectively.

Full Text

Blind people always have difficulties to access some information. So the braille language symbols are used to overcome this problem. With this modern technology, the refreshable braille cell was created. This cell is using piezoelectric concept. This refreshable braille cell can refresh the character. The pin for each braille cell is controlled by using piezoelectric bimorph. This will make the pin to rise and down. In this paper, the refreshable braille cell is controlled by the Arduino microcontroller and gets command from the Braille Key Module. The software use for this program is Arduino which use C+ language. The system is tested and successful.

Full Text

Rehabilitation therapy is the process to reduce the impairments and disabilities of upper or lower limb that are caused by accidents or stroke. This paper presents the design and development of a new hand rehabilitation device based on iris mechanism with basic Arduino coding to train the flexion and extension of the hand. The iris mechanism is designed using Solid Works 2015 and the prototype is developed using ABS filament and perspex. The steps to design the iris mechanism is shown in this paper, starting with the first layer (lower body), then the blade, second layer with gear, and third layer (for holding all layers together). The measurement of inside diameter is decided by considering the average size of object can hold by the patient for basic daily life. The inside diameter of the iris mechanism varies from 15 mm to 110 mm to enable the patients to adapt to various object sizes. The device can be used for the right-handed or left-handed person. The preliminary output shows that the designed mechanism is able to perform the opening and closing motion for the rehabilitation of hand function. The holding rod of the mechanism opens to the maximum 110 mm as the second layer with gear is rotated 770.

Full Text

A radial basis function neural network (RBFNN) based adaptive sliding mode controller is presented in this paper to cater for a 3-DOF robot manipulator with time- dependent uncertainties and disturbance. RBF is one of the most popular intelligent methods to approximate uncertainties due to its simple structure and fast learning capacity. By choosing a proper Lyapunov function, the stability of the controller can be proven and the update laws of the RBFN can be derived easily. Simulation test has been conducted to verify the effectiveness of the controller. The result shows that the controller has successfully compensate the time-varying uncertainties and disturbances with error less than 0.001 rad.

Full Text

NIR (near infrared) spectrometer utilized a quick reliable mean of molecular chemical detection. In this paper, we propose a method on authenticating fats originated from beef, chicken and lard. These compositions can be identified by NIR spectrometers through qualitative and quantitative analysis. Yet most of the analysis lack the capacity to find a pattern in the spectrums to be used in classification or regression models. The disadvantage of spectrum after all is the inability to show the concentration of fatty acids, yet these fatty acid components are shared by all kinds of fat/oil. Therefore, a new method is proposed to create a clear and a distinguishable pattern for the classification. The spectrum of each group (beef fat, chicken fat and pig fat lard ) of samples were acquired using a readymade micro-NIR spectrometer. The raw data required further processing before using it in the classifier. These processes including standard normal variant and Savitsky- Golay smoothing. Furthermore, the processed data was classified using support vector machine (SVM) with polynomial kernel. The trained SVM model showed 98.33% accuracy for 10-fold cross validation and 86.67% accuracy for unseen/testing data. For each individual kind of fat the model was able to identify the unseen data satisfactorily as follows lard with 100% accuracy and combined, chicken and beef showed 80% accuracy.

Full Text

Carbon nanotubes (CNTs) were dispersed within polyester resin to improve the thermal properties and to understand the degradation mechanism and reaction kinetics of jute reinforced composite. Viscoelastic behavior via dynamic mechanical analysis, strain rate effect and hygrothermal behavior of CNT filled jute composite were studied. The crystallization kinetics and microstructures were investigated with differential scanning calorimeter (DSC), X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Multiwalled CNT with 0, 1 and 3wt% was added within polyester resin matrix, whereas around 70% volume fraction of jute fiber is maintained in each sample. In dynamic mechanical analysis (DMA), 3% CNT filled composite showed better storage modulus and loss modulus values before the hygrothermal test. Due to the exposure to temperature (80oC) and relative humidity (95% RH) for 15 days in environment chamber, both storage and loss modulus of this composite
reduced by around 10%.

Full Text

Available Transfer Capability (ATC) computation of power systems including an excessive wind power penetration became a vital issue for system operation and planning due to the uncertainty and fast variation of wind speed. This paper proposes Probabilistic Collocation Method (PCM) for ATC determination with a grid connected hybrid wind power system. The low-order orthogonal polynomials are utilized to generate the approximation of the random variable of interest as the function of uncertainty parameters. The proposed method is a computational effectual solution to specify quite an precise approximation for the given probability distribution (PD) of system response. Consequently the method can significantly lessen the computational time compared to the traditional Monte Carlo (MC) approach. Examples are given on the IEEE 39 bus system to illustrate the effectiveness of the proposed method.

Full Text

In this study explain about the design and development of small electric vehicles (EV) using power inverter. Fully electric vehicles with multiple drivetrains allow a significant variation of the steady-state and transient cornering responses through the individual control of the electric motor drives. As a consequence, alternative driving modes can be created that provide the driver the option to select the preferred dynamic vehicle behavior. This article presents a torque-vectoring control structure based on the combination of feed forward and feedback contributions for the continuous control of vehicle yaw rate. The controller is specifically developed to be easily implementable on real-world vehicles. In this paper, DC power will convert to AC power for AC motor drive of the electric vehicles. The design and accessories of this electric vehicle are including battery, controller and motor. In this paper also need to identify the advantages of the electric vehicles in terms of environment, energy and cost. Moreover, this study also focused to compare the performance of electric vehicle with DC powered, AC powered and engine.

Full Text

The goals of this flying robot are to provide an accurate and precise search, rescue, exploration and saving of accident victims and also to reduce rescue time constraint. The major task in designing this robot is able to recognize the human body figure and detect the temperature of human body while searching the victim. At first, the design of robot s body will use base on coaxial helicopter. After that, system and recognition of human body figure system which uses the machine vision knowledge. Moreover, obstacles avoidance system, navigation system and flight level measurement system, communication system and temperature measurement system also included.

Full Text

This work answers the need for improvement in fuel economy in heavy duty vehicles (HDV s), in a manner simple enough to be used in open road missions. A look ahead anticipatory control (LA) method is designed to adjust longitudinal motion (signified by velocity of the vehicle system) using knowledge of fluctuations in road grade. The prediction of driving behavior is done using a fuzzy logic function based on a predefined rule-base. Control action of the brake and throttle positions are implemented by taking the state-dependent riccati equation approach. The results of the proposed controller are compared against those of a standard PI cruise controller. Moreover, results of simulations on a 40 ton vehicle show the proposed method capable of increasing fuel economy.

Full Text

In this paper we proposed a new control method based on Quantitative Feedback Theory (QFT) to design practical controller methodology for uncertain characterized with three degree of freedom flight control module. Again linearly least phase systems must sacrifice to desirable feedback control benefits to avoid an excessive uncertain disturbance. While preserving the robust stability Quantitative Feedback Theory (QFT) controller is proposed to control highly uncertain plants. A 3-DOF flight control system is intrinsically nonlinear, unstable and totally uncertain because of the nature of three individual angles known as pitch, elevation and travel. Most controllers which are designed for 3-DOF helicopter flight systems are base on a minimal linearized model where system variants and uncertainties are not accommodated. Again, the controllers are mostly designed to gratify the gains and phase margin specifications that may not guarantee to handle the sensitivity. In proposed controller QFT may explicitly deal with uncertainty, where large plant parameter uncertainties with lower bandwidth can be achieved by QFT controller. Pre-filter technique may improve both robust stability and robust tracking performance within a desired precision of the individual uncertain parameters of 3-DOF module. This controller may handle large parameter uncertainties and disturbance with rugged stability. The random optimization technique is engaged in the design to optimize the overall performance of the controller. Simulation results and equations are used to show effective result of the proposed control methodology.

Full Text

Extensive research efforts has been made in the conventional drilling of glass fiber reinforced polymer, where most researches focused in the studies of drilling parameters and thrust force relationship to delamination and tool wear. The effect of drilling generated heat was suggested frequently in these studies, but not many in-depth researches was done in this area. In this paper, an experiment was performed to study the effects of thrust force and drilling generated temperature generated from drilling parameters on delamination factor. A response surface method (RSM) integrated model consist of two phases was developed. The first phase of RSM modelling explained the relationship of drilling parameters with thrust force and drilling generated heat as mediator. The relationship between the mediator and the delamination factor were developed in the second phase of RSM modeling. The final RSM integrated models were validated and it resulted in a low percentage error delamination factor estimation equation from drilling parameters, while understanding and controlling the thrust force and drilling generated temperature

Full Text

Material flow during friction stir welding (FSW) is a challenging subject that should be studied to understand the defects produced during the process. Recent achievement of friction stir welding of polymers, necessitates the study of this process on polymers as well. In this paper material flow was studied on nylon-6 due to its wide engineering applications. For this purpose, a 1.5 mm thin polymer sheet, different in color, was used as a marker material and embedded in nylon-6 at various positions. Post-weld specimens, welded at optimum friction stir welding parameters, were cut at different sections for visual analysis of flow. Results showed that flow behavior in polymers is remarkably different from metals. Flow was limited to the pin influenced zone and no flow across this zone was seen. Uniform stirring and interesting phenomenon of far off displacement of plasticized material, even out of pin diameter range was observed. Analysis also revealed the upward vertical motion of the marker material.

Full Text

Upon cooling down from a high fabrication temperature, residual stress will be generated within the joint of ceramic-metal components. The stress is originated from the difference in thermal expansion between ceramic and metallic substrates. The excessive internal stress always leads to premature failure of the joint due to cracking or debonding. In this work, distribution and magnitude of residual stress in cylindrical sialon-AISI 420 stainless steel-sialon joining have been evaluated numerically using ANSYS software by varying the thickness of the steel. The simulation has been performed under pure elastic deformation and several other assumptions. Three stresses are evaluated namely radial, axial, and shear stress. Most parts of the sialon are in compressive mode whereas majority of the regions in the steel have experienced tensile radial stress. The maximum tensile axial stress is located at the free edge of the sialon and at the centre of the joint. Meanwhile, the maximum shear stress is concentrated at the edge of the interface. Increasing the thickness of the steel has reduced the radial stress but the stress that acts in axial direction is increased. The radial and axial stress exhibit constancy in joining to steel with thickness more than 10.0 mm. Regardless of any thickness of the steel, the shear stress practically remains unchanged. Comparison to diffusion bonded sample has validated that the developed stress is lower than the fracture stress of the sialon since neither sialon nor reaction layer contains any crack.

Full Text

Pineapple fiber which is rich in cellulose, relatively inexpensive, and abundantly available has the potential for polymer reinforcement. Pineapple leaf fibers (PALF) is the natural fiber that has good potential reinforcement in the yarn production. This research is done to investigate the mechanical properties of PALF in the form of single fiber and the twisted fiber. There are 3 type of sample which is 15 minutes, 30 minutes, and 45 minutes. There have 2 sample which is single fiber and twisted fiber. After undergo the treatment, fiber used to be measure the diameter using video analyzer that contain microscope to determine the diameter. After that, twisted fiber used to take the twist per inch (TPI) of every twisted fiber. Tensile test used to be run to get the load and time when test is run.This research presents a study of the mechanical properties of pineapple leaf fiber and pineapple peduncle fiber reinforced polypropylene composites. Composites were fabricated using leaf fiber and peduncle fiber with varying fiber volume fraction. Both fibers were mixed with polypropylene composites by various fiber volume fractions of 2, 4 and 6%. The composites panels were fabricated using injection molding machine. The tensile test was carried out in accordance to ISO 527-5A while hardness test accordance to ASTM D2240. The result showed that pineapple peduncle fiber with 2% fiber volume fraction give the highest tensile properties and pineapple leaf fiber with 6% give the highest hardness properties. From the overall results, pineapple peduncle fiber shown the higher tensile properties compared to pineapple leaf fiber, however pineapple leaf fiber shown higher hardness properties compared to pineapple peduncle fiber. It is found that by increasing the fiber volume fraction the tensile properties has decreased while hardness properties has increased. From the analysis done, there is a significant effect of fiber volume fraction on the tensile and hardness properties.

Full Text

The fundamental objective of this work is to investigate the performance of Ferrolubricants under a combined effect of magnetization and fluid behaviors. Two types of fluid models were investigated for further improvement of hydrodynamic journal bearing performance. Lubrication of finite hydrodynamic journal bearing lubricated by ferromagnetic fluids under the influence of Power-law and Couple-stress fluid models. By taking into account additives volume fraction, magnetization effect by the magnetic coefficient and fluid models (Power-law and Couple-stress) due to the microstructure additives. The fundamental approach involves a general modified form of Reynolds equation. The results showed an increase of pressure distribution within the fluid film whereby load carrying capacity of the hydrodynamic journal bearing improved.

Full Text

T-junction, or commonly known as stand pipe appendage, is used by oil/gas industries to tap gas from existing production header for the purpose of downstream pipeline instrumentation. The appendage is either pre-design or retrofitted with minimum internals for maximum reliability for remote deployment. The motivation for this research originated from the lack of stand-pipe design method to correctly account for the splitting/separation nature of multiphase fluid within the pipeline straight from the production header. Consequently, a certain amount of liquid migrates together with the gas, resulting in the so-called carryover issue. This situation is further aggravated by the different flow regimes in the header pipeline which is not taken into account by the design practice. The negative consequences of this carryover on the operation of downstream unit have often led to frequent trip and maintenance issues. This paper presents the preliminary research in the finding of the two phase oil/gas separation in T-junction. The computed solutions are compared with experimental data and a good agreement is achieved.

Full Text

Underground pipelines are susceptible to physical degradation due to the effects of hydrogen permeation which can lead to metallurgical damages, which in turn will affect the service quality. This study employs the use of electrochemical technique to analyze the effects of hydrogen diffusion coefficient on carbon steel coated with Polyaniline (PANI) -modified epoxy in soil solutions at different potentiostatic charging conditions. The protective behavior of PANI-modified epoxy was investigated using adhesion test, hydrogen permeation test and potentiodynamic polarization measurement. The hydrogen diffusion coefficient was determined by the time lag method. The results from these experiments suggest that PANI-modified epoxy is a considerable option for hydrogen barrier coating for steel pipelines in soil environments at certain charging potential.

Full Text

The effect of the rocker ratio, and the distance between the crank and rocker extreme positions, of a general four-bar mechanism with an extended rocker arm length are analyzed. The crankshaft rotation was set at a constant rate of 2000rev/min, and all mechanisms had the same strokes. A constant input force of 100N was applied at the rocker tips of all the mechanisms having a unit ratio of 1. A computer program using MATLAB code was developed for the kinematic and dynamic analysis of the crank-rocker mechanism to solve the governing equations. The results obtained from aforementioned analysis were plotted, compared and verified with the results obtained from ADAMS Software. It is concluded that the variation of rocker ratio did not have any effect on the rocker angular acceleration and torque output. However, a shorter distance, i.e. shorter connecting rod, is better than a longer connecting rod in terms of the peak values of angular acceleration and torque output. The results of the analytical solution were in good agreement with those obtained from ADAMS within 2% error. The findings are very significant for the improved design of the mechanism in term of power and packaging advantages.

Full Text

A characterization and resistance to corrosion study of parts made of steel, which are protected by nickel-alumina composite coatings, has been carried out. The influence of various experimental parameters has been considered. Various techniques of characterization have been used to study the coatings, namely the scanning electron microscopy, the atomic force microscopy and the X ray diffraction. Subsequently, the coatings have been submitted to a solution of NaCl in order to study their resistance to corrosion. For that purpose, the corrosion rates have been obtained using polarization tests. Thanks to this work, some interesting results have been obtained, such as the determination of the the coatings morphology. The most appropriate electrical current densities to obtain more resistant coatings have also been determined. Concerning the influence of the electrolytic bath, it has been found that the chloride bath allows obtaining coatings with better resistance to corrosion, compared to those electrodeposited in the sulfate bath. The influence of the bath temperature has also been considered and it has been found that the deposit corrosion rates do depend on the bath temperature and its optimum value has been obtained. The coating hardnesses have also been obtained.

Full Text

Conventional boron carbide powder particles of grain size 105 5m were blended with 1 %, 2 % and 3 % of nano sized (44-55x10-95m) boron carbide powder particles. The blended powder was sprayed on commercially available, grit blasted 410 grade steel using high velocity oxy fuel technique. Vickers micro hardness tester was used to measure the hardness value on the surface of coated and un-coated substrates. Worn surface morphologies were observed using scanning electron microscope. The presence of elements of boron and carbide were confirmed in the analysis. Pin-on-disc tribometer was used to study the tribological behavior of these coatings as per ASTM G99 standard. The results indicate that the increase in the amount of nano powder in the blend significantly increases the hardness and wear resistance compared to only micro boron carbide coated and un-coated steel substrates.

Full Text