To distribute the products, the company uses tools such as breadbox that is place in the motorcycle seat. However, the tools used for these motorists complain of discomfort, this is due to the rigid box shape (on the back of the rider) and the improper size of the box. Ergonomics or human factors considerations are very influential in the driving comfort. This study aimed to design an ergonomic breadbox, accordance with aspects of anthropometry. Ergonomic breadboxes are useful for bikers to bring bread to the stalls. The purpose of the breadbox design is to enhance the previous design. Specifications of breadbox concept design are; box shaped, forming a body curves and ergonomic seating position on the side of the backrest, made of fiber material, backrest follow the shoulder width, and box cover is not covered with plastic.

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This paper reports correlation on leakage current and thermograph infrared (IR) images of the ceramic outdoor insulator for the condition based monitoring purposes. In this work, laboratory pollution performance test using sodium chloride was performed according to the IEC 60507 standard with applied AC voltage from 12 kV to 18 kV. The severity level of pollution were controlled and represented by ESDD values of 0.00 to 0.25. Also relative humidity conditions were controlled on the range between 60% to 100%. Statistical parameter of infrared images were evaluated to assess the severity level of contaminated ceramic insulator. The output IR images of the insulator were categorized as safe state, necessary maintenance and dangerous based on the level of contamination severity. The results showed that the severity of the pollution can be identified based on the analysis of infrared images, where each severity level of leakage current was correlated with a particular color. Also, it was found that the phase difference between the leakage current to the reference voltage decreased along with the increase in the severity level of pollution.

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In this study energy consumption of conventional fan coil unit and five models of desiccant cooling system are evaluated for application in one seminar room in hot and humid area. The energy usage of FCU and desiccant cooling systems are detected by measurement and simulation respectively. The measurement results demonstrated that the average energy consumption of FCU per day is 61.8 kWh that 7%, 27%, and 66% of the total energy consumption of FCU belong to the fan, pump, and chiller, respectively. Simulation results shows that among the five proposed models, the one-stage hybrid desiccant cooling system (model C) can produce suitable conditions for the room.

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Ejectors have been used in refrigeration systems application for ages. researches are applying ejectors in refrigeration systems to minimize energy consumptions by harnessing renewable energy. This paper presents CFD model to study and analyse the effect of exit nozzle position (NXP) on the ejector performance. The most important parameters that affect the performance of an ejector are the pressure and temperature, variable pressure and temperature were applied in this study to find the optimum entrainment ratio at different position of NXP. The NXP can be controllable by using a spindle feature which moves NXP forward or backward. Also the mass flow rate that enters the ejector is controlled by another spindle. By using these both features, two parameters can be controlled separately. From the simulation results, it was found that the optimal entrainment ratio Er can be obtained at different position based on the operating conditions. The range of Er was from (0.24-1.12) at constant area ratio and varied operating conditions.

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Peat water can be used as drinking and raw industrial water if it has been treated to eliminate the chemicals content, especially organic carbon. In this research, heterogeneous photocatalytic by TiO2 photocatalyst could be an effective alternative solution to eliminate total organic carbon from the peat water under reduced side effects. TiO2 films as a photocatalyst synthesized by screen-printing technique was achieving 0.0053 mg/cm2 TiO2 loading. The characterization for the physicochemical properties of photocatalysts carried out by X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR), Thermal Gravimetric Analysis (TGA) and Scanning Electron Micrograph (SEM). The smooth enough surface TiO2 anatase film was showed by SEM and the film thickness ± 0,175 µm on glass support. XRD analysis conducted on TiO2 photocatalyst powder inform the thin layer of photocatalytic TiO2 before and after shows only the peaks of crystalline anatase with an average crystal size of 142 nm . The results show that the specific surface area of photocatalytic TiO2 before coating 11.786 m2/g and increased 134 % after coated to support the glass but did not significantly change during the photocatalytic process. TiO2 film was success applied as solar UV-TiO2 photocatalytic reactor to degrade total organic carbon (TOC) in peat water for long time duration. TOC was degradated as 94 % after irradiation for 6 hours and water became neutral.

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Biosorption is the process of removal metal ions containing in the solution using agricultural by-product. The research was used stem tree of soybean for Pb(II), and Zn(II) in fixed bed continuous flow column. The experiment was studied for the flow rate of solution and mass of stem tree of soybean. The optimum of sorption capacity for Pb(II), and Zn(II)) metal ion is 12.44, and 6.752 mg/g on flow rate 2 mL/min and 0.1 g mass of stem tree soybean. The simulation of the breakthrough curve was successful with the BDST model. The design of fixed bed column for Pb(II) and Zn(II) removal from wastewater by biosorption onto stem tree of soybean can be done based on the BDST model.

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The prospect in using a bio-adsorbent corn stalk to remove metal ions from solution in batch operation was investigated. Corn stalk with shapes variation has ability to remove single metal ion in aqueous solution over than 80%. In binary metal ions solution, the competition of Cd2+ and Cu2+ to adsorb on adsorbent surface at pH 4.5 was then studied. With concentration variation ratios such as: 20:40; 30:30 and 40:20 were found: Cd<Cu; Cd>Cu and Cd>Cu respectively. The total removal ability was almost the same at 62.5% for each concentration variation. The adsorption kinetic results are appropriate with the second order of kinetics equation model and diffusion equation model. It is indicated that the interaction of metal ions on corn stalk occurs chemically. The adsorption tends to take place on porous area of the adsorbent. The adsorbed diffuse to internal site of adsorbent. The ability of corn stalk to adsorb the metal ion shows its potential as a natural adsorbent.

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This paper focuses on evaluation of micro hydropower plant (MHPP) that applies overall equipment effectiveness (OEE) method. MHPP are used on the rural electrification and does not necessarily supply electricity to the PLN grid. They are utilized in isolated and off-grid systems for decentralized electrification. Some identified issues or problems are the results of insufficient site assessment, poor quality of power plant facilities and electro-mechanical equipment, controller equipment and inadequate operation and maintenance. To determine performance of MHPP is done the evaluation using OEE method especially some of the MHP in districts South Solok. The first step is observing the real condition of MHPP to find technical or non technical of primary and secondary data. The data are classified according to wich needed by OEE method. It has three main components such as availability, performance and quality. There are seven MHP as the research object. The results are obtained an availability average i.e. 68%, performance average i.e. 52% and quality average 67%. These achievements shown the MHPP production only reached a value of OEE i.e. 38%. Therefore, the production in the standard of the Japan Institute of Plant Maintenance (JIPM) is a bad class. The strong issues or problems of MHPP that found are management 17,2%, control systems 7,3%, turbine 10,6%, generator 32,7% and transmission 31,9%. Management includes costumer payment, skill of the operator and maintenance. Generators are major contributors to the problem because there are many MHPP does not have automatic control equipment.

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Fiberglass industry is an industry that uses polyester reinforced with fiberglass as the main raw material. Various products can be made by using fiberglass. The diversity of products in the fiberglass industry often pose a problem, that is difficulty in determining when the work can be completed. Timeliness is critical to customer satisfaction. By utilizing visual feature recognition approach of the product to be produced and Artificial Neural Network, the production time based on feature standard time-making is predicted. This study consisted of modelling decision support system using artificial intelligence algorithms, testing alternative models, developing decision support system software, software testing to confirm the results with the real in field situation. With this system, fiberglass industry is expected to be able to maintain customer satisfaction by completing the work on time. By using a neural network, the timing of the completion can be done more accurately and the latest production data became the basis for considering the production time for the next orders.

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This paper presents the design of an active power filter (APF) with soft switching. APF used for compensating the power factor harmonic and harmonic current, but usually switching losses is increased when APF operates at high frequency. The switching losses can be reduced by soft switching technique. The proposed soft switching losses can be reduced by soft switching technique. The proposed soft switching APF includes the combination of the boost converter with auxiliary resonant. By using an auxiliary resonant circuit, switching losses of APF is reduced and the circuit forces voltage or current to zero for the duration switching. The advantages of proposed design improve efficiency, reduced voltage stress, and greatly reduced harmonic current of voltage source. The proposed soft switching APF rated at 500 W and operated at 10 kHz. It can achieve a sinusoidal line current and near unity power factor. In order to verify the proposed design a simulation model using Matlab/ Simulink was developed. The results show that the proposed APF can significantly reduce the total harmonic distortion (THD) and improve the power factor.

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Oil Palm empty fruit bunches (OPEFB) is the solid waste produced from crude palm oil industries. It comprises of cellulose, hemicellulose and lignin. The major component of hemicelluloses, xylan, is a complex heteropolysaccharide with a ß-1,4-xylose backbone. In the utilization of xylan, it must first be hydrolyzed into its components, that are the 5 carbon atom sugar xylose and arabinose. Endoxylanase (xylanase) is the primary enzyme that attacks the backbone structure of hemicellulose by random cleavage of internal xylosidic linkages to produces the xylose hydrolisate. Further xylose can be used as raw material for the production of a wide variety of chemicals such as xylitol. Enzymatic hydrolysis of xylan to xylose using xylanase offers an environmentally friendly biotechnological process beside performed at ambient temperature and pressure, it also has high specificity and low cost. Previous research has shown that fungal species Trichoderma is a good producer of lignocellulosic enzymes including xylanase. This article describes the study of enzymatic hydrolysis of OPEFB using crude xylanase extract produced by Trichoderma viride ITB CC L67. The study focused on the optimation of hydrolysis process in terms of temperature and pH. The optimization was done based on Response Surface Methodology (RSM) to give either the optimum xylose concentration or xylose to glucose concentration ratio. Further, the kinetics of the enzymatic hydrolysis process of OPEFB was studied. The enzymatic hydrolysis can be well approached by the Michaelis Menten kinetic model, and kinetic parameters were obtained from experimental data.

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A Proton Exchange Membrane Fuel Cell (PEMFC) is developed as a potential solution in power supply applications. Performance of PEMFC was depicted by current density and voltage. The water liquid content in PEMFC depend on several factors. Current density is one of factors that affect water liquid formation in PEMFC. This study aimed to know the influence of current density of water liquid formation in Cathode. The result was shown that at temperature from 303 K to 333 K, the water liquid formation was small at higher current density. At current density above 1Acm-2, it makes little difference of water liquid content. Increasing the temperature (about 343 K) will decrease the performance of PEMFC, which is Relative Humidity Cathode (RHC) 50% and the Relative Humidity Anode (RHA) 90 %..

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The degree of mixing is one of the main indicators of the combustion performance in a combustion chamber. The higher the degree of mixing, the more intensive the contact/reaction between the air and the fuel, so that the combustion performance is getting better. The degree of mixing in a combustion chamber is indicated quantitatively by several variables such as the velocity profiles, the flow structure and the turbulence intensity. The degree of mixing in a combustion chamber is influenced by the factors of geometries and operating conditions. This study is aimed to determine the effect of the inlet aspect ratio (RIA) to the mixing characteristics in a tangential burner. The investigation methodology used in this study is based on the numerical simulation with the Ansys-Fluent simulation code as a Computational Fluid Dynamics (CFD) engine. The fluid flow modelings are performed with the standard k-? turbulent model. From the simulations that at mesh interval size smaller than 7 % of the chamber diameter, the standard k-? model is able to match satisfactorily the tendency of the experimental velocity profiles available in the literature. The simulation results also show that the inlet aspect ratio has a significant influence to the mixing characteristics in the tangential burner. Within the RIA value that is tested, the best mixing characteristic is found on the burner with the RIA value of 10. The formation of the tornado tail flow structure is determined by the inlet aspect ratio, the total mass flow rate and the swirl number.

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The promising technology to assess the susceptibility of ammonia-treated of lignocellulosic biomass potential to enzymatic hydrolysis in bioconversion process to biofuels is Simon’s Stain measurement. Fundamentally, the porosity and the overall surface area of lignocellulosic substrate will successfully increase by the pretreatment process; as the major structural feature influencing the hydrolysis of pretreated substrates by cellulases. The modified of Simon’s Stain method was used in this study by decreasing the processing time from >50 to 6 hours, is the semi quantitative method for estimating the available surface area of ammonia-treated OPEFB and SSB. The materials, oil palm empty fruit bunches (OPEFB) and sweet sorghum bagasse (SSB), were soaked into aqueous ammonia for 1, 2 and 7 days in room condition. The data shown, the maximum dye adsorbed on the ammonia-treated materials was increasing as raise the pretreated-days as well. The total dye adsorption correlated well with the enzymatic hydrolysis yields resulting in good correlation coefficient (R2). This method proved to be an effective tool for assessing the potential of cellulase to hydrolyze the lignocellulosic substrate.

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Gambier is a kind of sap that comes from compressed extract of leaves and twigs of gambier plants (Uncaria Gambir Roxb.). The use of gambier is being developed for natural dye of textile products such as weaving yarn. Previous research showed that solution of gambier 5% had been good enough to be used as a textile dye. Gambier residual dyeing solution is liquid waste that still contains active ingredients namely tannins and catechins which still can be reused. This study was aimed to see whether the waste can be reused for dyeing and to see the quality of products. The study was conducted using cotton yarn and mordant Calcium Oxide (CaO) with 2 treatments namely dyeing time (5, 15, and 25 minutes) and kind of liquid waste (1st reuse and 2nd reuse). The utilization of fresh gambier solution was done as a control. The results showed that gambier liquid waste of dyeing still contain tannins up to 52.14% and still can be used as a textile dye. The dyed yarn quality using 1st and 2nd reused dye waste showed that for all treatments, color fastness on washing 40°C as well as on dry ironing heat were good to excellent (4-5) averagely. The results were not significant compared to yarn quality which was dyed with fresh gambier solution. Color fastness on sunlight in dyeing with 1st and 2nd reuse were moderate until fairly (2-3). The results were lower compared to dyeing with fresh gambier solution that had an average value ? 4 (good). Dyeing treatment affected the color strength value. Dyeing with 1st and 2nd reuse generated a darker color than dyeing with fresh gambier solution. Dyeing in 2nd reuse had the highest color strength with K/S value 13,810-16,871.

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The raw data PD measurement results by using a computer usually contain noise that can lead to miss interpretation. So as to obtain an accurate diagnosis, then this noise must be separated from the raw data. In this study, the electrodes used were needle-plane electrode and the samples tested are polymer films placed on the electrode plane and the air gap is located between the needle and polymer films. There are two types of arrangement of the electrodes, the first electrode needle wrapped with the film and the second polymer are not wrapped with polymer films. To separate the data PD of raw-data is necessary algorithms that can automatically select the threshold value of the standard deviation value. To obtain the optimum value, the threshold value selected based on the standard deviation of each value segment. The results show that this method has been used to distinguish between the electrode pattern PD wrapped or not wrapped polymer.

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The high content of secondary metabolites in the cacao peels extracts, has the potential to be used as a corrosion inhibitor on mild steel. Effect of polar extract of cacao (Theobroma cacao) peels to the inhibition of corrosion, adsorption properties and mechanical properties in 1.5M HCl solution have been conducted on mild steel. Methods of weight loss, potensiodinamic dan impedance to determine the corrosion rate and efficiency of inhibition, as well as tensile and hardness testing for mechanical properties was conducted with the concentration of extract (0.5-2.5) % by an interval of 0.5%. The surface morphology of samples was observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Energy dispersive X-ray spectroscopy (EDX) was used to examine the chemical composition of the surface. Corrosion rate is reduced and efficiency is increased with the increase in the concentration of the extract. The increase in the concentration of the extract is followed by an increase in mechanical properties, namely hardness, strength and fatigue strength. Chemical adsorption is characterized by an increased in the degree of surface of coverage with the rising levels of carbon in the surface of the mild steel with increasing concentrations of the extract. Adsorption isotherms are in accordance with the Langmuir adsorption. The presence of adsorption on the surface of the data is reinforced by EDX, X-ray photon spectroscopy) XPS and X-ray diffraction (XRD) AFM for topography. The addition of polar extract of cacao peels into HCl 1.5M solution is very effective to reduce the attack of corrosion on the surface of mild steel and it can retain mechanical properties of the mild steel after the corrosion.

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Backpack is one of the essential equipment that must be owned by a nature lover or a mountaineer when doing the adventurous activities. There are various types of backpacks on the market with a variety of brands, shapes and sizes according to the desires and needs. However, there are still complaints from the users when or after using those bags. Therefore, this study was conducted to analyse the backpack from the ergonomics side, specifically the influence of the use upon the body muscle and the heart muscle tension on three types of mountaineering backpacks that are often used namely Pack X, Y and Z. This study used Surface Electromyography (EMG) to analyse the muscle activity, Electrocardiography (ECG) to analyse the electrical activity of heart muscle, and Nordic Body Map (NBM) questionnaires to investigate the user perceptions of musculoskeletal discomfort. Twenty nature lover students were participated as the subject in the study. EMG and ECG data retrieval as well as filling out the NBM questionnaire performed before and after simulated trip for an hour using the treadmill in the laboratory by 20 subjects. The results indicated that Pack Z is less ergonomic than Pack X and Pack Y. The study also generates some criteria in choosing the ergonomic backpack based on analysis of muscle and heart electrical activities of the subjects.

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The shortcoming of fuel in the future has forced by the government and car manufacture to find new power source to propel the vehicle. Electric vehicle is one of solution of this problem. The aim of this research is to investigate main component of propulsion system of electric vehicle namely battery, DC-DC converter, motor drive and motor. Since building actual vehicle is expensive, the component ratings were reduced to save money. From the experiments, it was found that each component need is critical and need detailed analysis to produce a reliable and energy-efficient electric vehicle.

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