bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Plastic Optical Fiber Based Daylight System Suitable for Building Applications
Authors: Maskarenj Marshal Shahu , Avasare Mahesh , Ghosh Prakash C.
Published: January 2014

In the scenario of world energy crisis, building energy efficiency has become a mainstream research focus; since buildings take up a large share of the world energy consumption. Lighting plays an integral part in the buildings operationality through providing indoor visual comfort; and the much-needed daylight harnessing in building structures can be achieved through various strategies. This paper aims to evaluate the amount of plastic optical fiber (POF) required for achieving optimum indoor illumination through light transport and study the advantage of two dimensional solar tracking and light concentration on indoor daylight enhancement through POF as a trade-off for the amount of POF required in a static system. Illumination attained inside a representative closed chamber due to light transported by POF via various mechanisms was experimentally compared with outdoor direct illumination and the amount of POF required for achieving comfortable indoor illumination was calculated for a proposed system involving tracking and light concentration. A microcontroller based dual-axis solar tracker was designed for tracking sunlight on the POF collector node every 10 seconds and opaque internally reflective plastic containers acted like sample rooms in a building. Calculations for the representative day normalized for the flooring area in an office building showed a promising payback period of around 5 years through partial replacement of electric lighting. Additionally, reduction in heat conduction through window glazing further reduces the cooling costs.
The Simulation Study of Transformer Inductive Oscillating Switching Impulse Voltage Generation
Authors: Liang Ji Chong , Wang Tian Zheng , Wang Kang Ning , Li Jun Hao
Published: January 2014

According to IEC60060-1, IEC60060-2 requirements, the large transformer should take impulse voltage test in site. However, this test is not performed in the field for the impulse voltage generator huge and difficult to operate. To solve this problem, IEC60060-3 propose using oscillating impulse voltage for equipment on-site impulse withstand voltage test. Oscillating impulse voltage has higher generation efficiency and close to the actual voltage waveform that electrical equipment bear. For the transformer, the oscillating impulse voltage can generated through inductive method. In order to study the generation of oscillating impulse voltage through inductive method for transformer, the simulation circuit is established using ATP soft and the oscillating switching impulse voltage characteristics is studied in this paper. The result show that the oscillating switching impulse voltage waveform that accordance with IEC requirements can be generated through inductive method for transformer.
A Novel Research and Implementation of Dynamic Voltage Restorer
Authors: Pei Su Ping , Wu Fu Zhuan
Published: January 2014

This paper discusses a novel research and implementation of dynamic voltage restorer (DVR).The phase diagram is shown based on the principle and the steady-state equivalent circuit. The initial phase of the source fundamental voltage and angle are given according to instantaneous reactive power (IRP) theory. The voltage function is determined by the optimum voltage injection angle which is based on minimum energy compensation (MEC). A prototype and the design process are given. The experimental results verify the rationality .
Fabrication of Porous Titanium Dioxide Film by Oxidization of Titanium Foil and its Photocatalytic Performance for Degradation of Methyl Orange
Authors: Pan Rong Jun
Published: January 2014

Porous titanium dioxide film is an important photocatalyst. To bridge the gap between the application and traditional preparation of porous TiO2 film, an approach was developed to achieve porous TiO2 film by oxidization. SEM and XRD were used to characterize the morphologies and crystalline structure. Photodegradation of methyl orange was performed to investigate the photovoltaic performance. The results reveal: (i) the film obtained by oxidization has irregular porous structure with many protuberances on its surface, pore diameter ranging from 20 to 300 nm, and an average thickness of 40 μm, while that fabricated by potential anodization was highlyordered with pore diameter of about 50 nm and thickness of about 6 μm; (ii) the former has anatase structure after being calcined, while the latter contains anatase and titanium; and (iii) the former has higher adsorption and photocatalytic activity than the latter.
Energy Requirement Estimates for Two Step Ethanolysis of Waste Vegetable Oils for Biodiesel Production
Authors: Ligeris Nikolas , Jalama Kalala
Published: January 2014

ChemCad 6.4 simulation package was used to model a two-step biodiesel production process from waste vegetable oils (WVO) and ethanol using homogeneous acid and alkali catalysts respectively. The developed process flowsheet consisted of pre-esterification and transesterification of WVO, ethanol and glycerol recovery, and biodiesel refining. The energy required for each processing unit as well as the energy required for the whole process have been estimated. Ethanol recovery accounted for the highest portion of the energy required for the entire process estimated as 2.75 MJ per kg of biodiesel produced.
A Charging Management of Electric Vehicles Based on Campus Survey Data
Authors: Yagcitekin Bunyamin , Uzunoglu Mehmet , Karakas Arif
Published: January 2014

Road transport electrification has a great potential to reduce greenhouse gas emissions and oil consumptions. However, massive integration of electric vehicles (EVs) may cause a trouble on power grid. This point of view looks at the future state of EV development, charging scheduling and drivers’ behaviors are becoming increasingly important to charging management strategy. An optimal charging management leads to minimum effects on power grid, reducing peak power via vehicle to grid (V2G) mode and lower charging costs. In order to make an optimum charging management strategy, it requires some information of driver behavior, such as daily driving, parking times and usage frequency of the vehicle. At this perspective, a campus based driver behavior is gathered with face to face survey in Yildiz Technical University, Turkey. Survey data is utilized to determine daily optimum charging profile and increase the functionality of EVs. In this study, the comparison of possible effects of different charging scenarios on power grid are presented and analyzed. A case study is performed in the university campus and the simulation is realized in MATLAB/Simulink environment with actual data.
Impact of Gas Turbine Frame Size on Efficiency of Gas Turbine Power Plants
Authors: Basha Mehaboob , Shaahid S.M. , Al-Hadhrami Luai
Published: January 2014

A computational study to assess the effect of gas turbine (GT) frame size on efficiency of gas turbine power plant configurations is presented in this paper. The work includes the effect of relative humidity (RH), ambient inlet air temperature and frame size on gas turbine plant configurations with and without fogger unit. Investigation also covers economic analysis. 20 MWe GE 5271RA, 40 MWe GE-6561B and 70 MWe GE-6101FA frames are selected for the present study. GT PRO software has been used for carrying out the analysis including; net plant output and net efficiency, break even electricity price (BEEP) and break even fuel LHV price (BEFP), etc. The relative humidity and temperature have been varied from 30 to 45 % and from 80 to 100° F, respectively. Fuels considered in the study are natural gas, diesel and crude oil. Results show that variation of humidity does not affect the gas turbine performance appreciably for all GT frame size regardless of type of fuel.
For a decrease of inlet air temperature by 10 °F, net plant output and efficiency have been found to increase by 4 and 1.7 %, 4.2 and 1.3 %, 4.7 and 1.8 %, respectively for 20 MW,40MW and 70MW for crude oil and for GT only situation. However, for GT with Fogger scenario, for a decrease of inlet air temperature by 10 °F, net plant output and efficiency have been found to further increase by 3.1 and 1.3 %, 3 and 0.9 %, 3.2 and 1.1 %, respectively for 20 MW,40MW and 70MW. For situations with and without fogger for crude oil, BEFP have been found to vary from 1.3968 to 1.3916, 2.13 to 2.0948, 2.387 to 2.4642 USD/MMBTU respectively for 20 MW, 40MW and 70MW and BEEP have been found to vary from 0.03142 to 0.0313, 0.02488 to 0.02504, 0.0229 to 0.0233 USD/kWh respectively for 20 MW, 40MW and 70MW.
Single-Ended Forward Switching Power Supply Design Based on UCC2800 PWM Controller
Authors: Yang Wei , Qiu Li Jun , Wang Yi Xiao
Published: January 2014

Switching Power Supply which has a lot of advantages compared with Linear Power Supply is used very widely in the modern life. This paper discussed a kind of DC/DC switching power supply based on the UCC2800 PWM controller chip, the basic technical indicators is DC 28V rated input voltage ranging from 16V to 40V, 5V30W output, and analyzed its working principle、soft start and short-circuit protection, finally, briefly described switching power supply design methods in the use of UCC2800 PWM controller chip.
Application and Contrast Analysis of BP and RBF Neural Network in Short-Term Wind Power Prediction
Authors: Li Wen Hua , Xiao Qian , Liu Jin Long , Liu Hui Qiao
Published: January 2014

Wind power prediction is very important to maintain the power balance and economic operation of power system. The BP and RBF neural network were respectively used to predict one wind turbines’ output power, in 4 hours, on a wind farm in Shandong Province. The results show that the BP model, with 6-13-1 net structure and considering the meteorological factors, exhibits the best prediction accuracy (MAPE is 3.59%, NRMSE is 1.58%). The most important factor in the meteorological information for power prediction is temperature, followed by air pressure, relative humidity finally. BP model is slightly better than RBF model, but the latter is much better in the learning speed and stability. Dynamic-BP neural network, combined with the dynamical weight adjustment method, is better than BP neural network in solving the weight problem. These methods are feasible to the wind power prediction.
Application of Advanced MPPT Control for Grid-Connected Wind Power Generation System
Authors: Wang Wu
Published: January 2014

The wind speed is varying with fluctuations and random feature, as for conventional HCS algorithm, the oscillation around maximum power point (MPP) was serious, which can cause vibrations of crankshaft and mechanical parts wear, also the misleading decision of conventional HCS method causes the failure in keeping maximum power. A new HCS method for MPPT control was proposed, the principle of MPPT was analyzed and new algorithm was programmed, the new method inherits the advantages of variable step HCS, so that the MPP reached rapidly. Also the detection and halt mechanism was introduced, which can reduce searching direction misleading and rotor speed oscillations at MPP, the feasibility and effectiveness of the proposed MPPT strategy have been verified through simulations and experimental results.
Analysis on a Gas Turbine Sealing Disk Structure and Material Strength
Authors: Liu Ben Wu , Wang Jian Jun , Yuan Hui Yi
Published: January 2014

To study the cause for fatigue cracking failure at pressure-balanced holes of a gas turbine compressor sealing disk, the damage impression, fractography and material composition of the damaged section were studied. Some manufacturing defects at the pressure-balanced hole edge were found, and the cracks at pressure-balanced holes are caused by high cycle fatigue (HCF). Stress analysis on the sealing disks of two types of different materials under assembly conditions and different structure dimensions were performed. The analysis results revealed that the high radial stress of pressure-balanced holes is the weak point of the original sealing disk design, and the manufacturing defects will prompt the cracking failure of holes. The studied work is valuable for performing similar fatigue failure analysis and new sealing disk structure design improvement.
Carbon Dioxide Effects on the Flammability Characteristics of Biogas
Authors: Hamidi Nurkholis
Published: January 2014

Flammability limits and flame speed of methane-carbon dioxide-air mixtures have been studied to understand the effect of carbondioxide on the flammability characteristic of biogas. The fuel of biogas discussed in this study was made by mixing gases of methane and carbon dioxide. The carbon dioxide was varied from 0% (by volume) untill reach the flammability limit of the stoikhiometri biogas-air mixtures. The observation was done using a cubic combustion bomb with the dimension of 500 mm x 200 mm x 10 mm with the initial condition being at room temperature and atmospheric pressure. The ignitor was set at the top of combustion bomb, so the flame propagated downward. Base on the observation results, the presence of carbon dioxide in the fuel ofbiogas caused the flammability limits of biogasair mixture narrower. The biogas-air mixture was still flammable with the highest content of carbon dioxide of 62.5 %vol when the mixture was sthoichiometri. Compared to methane-air mixture, the presence of carbon dioxide in biogas caused a reduction in the flame speed. The stoichiometri mixture has the highest flame speed when the carbon dioxide was not present in the fuel. However, when the carbon dioxide was added in the fuel, the rich mixture has the highest flame speed. This is a consequence of the rich biogas-air mixture having a higher fraction of the carbon dioxide components from the fuel compared to the stoichiometri and lean biogas-air mixture. The result also indicated that at the upper limit the flame still propagated downward to closed to the endwall. However, at the lower limit (lean mixtures), the flame did not intend to propagate downward, it was just at the top and propagate sideward.
Solar Driven Absorption Chiller for Medium Temperature Food Refrigeration, a Study for Application in Indonesia
Authors: Suamir I Nyoman
Published: January 2014

Indonesia has abundant renewable energy resources. In 2005 this country, however, only consumed 0.38% renewable energy of the total energy consumption. Most of the energy sources of the country are from fossil fuels which result in high CO2 emissions. Solar energy systems would be as an option to reduce the CO2 emissions of this country. This paper studied the application of solar energy to provide cooling for medium temperature food refrigeration based on Indonesian weather conditions. The paper additionally analyzed the environmental impact relating to CO2 emissions, and investigated the economical aspect. CFD-Fluent software was applied on modeling the modification of the absorption chiller generator to enable it to operate with heat from solar radiation, while F-Chart and Microsoft Excel spreadsheet were used to analyze the solar system and the economical viability of the technology. The results showed that the optimum modification of the absorption chiller was to use a jacket for heat addition. CFD modeling with Fluent using Diphyl THT as the heat transfer fluid (HTF) indicated that the system would function optimally at fluid temperature input of 180°C, whereas the optimum average temperature of the chiller generator would be 170 °C. The proposed technology was found economically less viable for food refrigeration compared to the vapor compression cycle using R-404A but it could provide a significant impact on the environment by a reduction of 37% CO2 emissions.
Flammability Limit and Flame Visualization of Gaseous Fuel Combustion Inside Meso-scale Combustor with Different Thermal Conductivity
Authors: Yuliati Lilis , Sasongko Mega Nur , Wahyudi Slamet
Published: January 2014

This study experimentally investigated effect of thermal conductivity on the combustioncharacteristics of gaseous fuel inside a meso-scale combustor. Combustion characteristics that wereobserved in this research include flame visualization and flammability limit. Quartz glass, stainlesssteel and copper tubes with inner diameters of 3.5 mm were used as combustors. Stainless steel wiremesh was inserted inside meso-scale combustor as a flame holder. Liquid petroleum gas (LPG),which is common fuel use by Indonesian people, was used as a gaseous fuel. A stable blue flame wasestablished inside meso-scale combustor at the downstream of wire mesh for all combustor withdifferent thermal conductivity. Furthermore, flame color is blue for combustion of fuel lean orstoichiometric mixture, and blue-green for combustion of fuel rich mixture. Meso-scale combustorwith the highest thermal conductivity has the narrowest flame cross section area, especially at lowerreactant velocity. Vice versa, this combustor has the widest flammability limit, mainly at the higherreactant velocity.
Case Studies Thermal Analysis of HP Condensate Stabilizer Column
Authors: Qirom Muhammad , Indarto Antonius , Putrawan I. Arsa
Published: January 2014

The HP condensate stabilizer column is located in the condensate stabilizer unit that functions to recover light hydrocarbons from feed. The HP condensate stabilizer column is a stripping column equipped with 15 trays, condenser, reboiler and a pump-around. The main purpose of HP column is to recover propane and butane components from feed condensate by a distillation process. This process is conducted by heating the liquid in the bottom of the column using steam. The amount of heat supplied is depend on the mass and heat balance in the column based on the targeted product quality from the bottom of the column. The product quality measured is Reid Vapor Pressure (RVP) that indicate the volatility characteristics of bottom product.
High-Efficiency Shrouded Micro Wind Turbine for Urban-Built Environment
Authors: Kosasih Bu Yung , Jafari S.A.
Published: January 2014

Shrouding (diffuser augmented) horizontal axis micro-wind turbine has been shown to be an effective ways to potentially increase the power output of micro wind turbine for applications in built environments. It is well understood that the degree of the performance enhancement depends on several factors including the diffuser shape and geometries, blade airfoils, and the wind condition at the turbine site. The effect of diffuser shape and geometries is reported in this paper. Computational fluid dynamic (CFD) simulations of a small wind turbine with a simple frustum diffuser shrouding have been carried out. The diffuser has been modeled with different shapes with the aim to understand the effect of length and area ratio on power augmentation phenomenon. The simulations provide some parameterized figures which present method to determine the beneficial range of frustum diffuser geometries for diffuser shrouded horizontal axis wind turbines.
Modeling and Analysis of Hybrid Shock Absorber for Military Vehicle Suspension
Authors: Guntur Harus Laksana , Hendrowati Wiwiek , Budiarto Tidy
Published: January 2014

This paper deals with the design, modeling and analysis of a hybrid shock absorber for vehicle suspension. A specific design of frictional-electromagnetic-regenerative shock absorber is proposed. The hybrid shock absorber consists of the proposed frictional-electromagnetic-regenerative shock absorber assembled in parallel with a conventional-viscous shock absorber. The concept of hybrid shock absorber is proposed due to the following advantages: the regenerative shock absorber will recover some wasted vibration energy from the suspension into electrical energy to support the need for electrical energy of the vehicle, while the viscous shock absorber maintains the performance of suspension closed to its original suspension. The vehicle suspension system dynamic was mathematically modeled for three different types of suspension:1).Conventional suspension using viscous shock absorber; 2).Hybrid suspension using combination of 50% frictional-electromagnetic-regenerative shock absorberand50% viscous shock absorber; and 3).Full regenerative suspension using 100% frictional-electromagnetic-regenerative shock absorber. In this research, 6 wheels military vehicle (APC:Armour Personal Carrier) is chosen as the model due to the high possibility of applying regenerative suspension to the military/off road vehicle. Based on the mathematical models, performances of the vehicle suspension and the regenerated power from regenerative shock absorber (RSA) were simulated. The results were compared between the three types of suspension and discussed.
Effect of Material and Process Parameter on Dimensions of Rolled External Threads
Authors: Chauhan P.S. , Agrawal C.M. , Dwivedi R.K.
Published: January 2014

The work in this paper presents the effect of material and blank dimension on the dimensions ofexternal rolled threads. This paper will be helpful for the auto industry, one of the largest fastenersmarkets, that typically consumes between 2800 to 3100 fasteners in the assembly of an average familyvehicle. Externally threaded fasteners comprise the bulk of fasteners used in these applications withover 90% of being produced by thread rolling. The thread rolling process is now widelyacknowledged as the fastest and most efficient method of producing accurate external threads, withsurface finish and mechanical properties. The typical production rates are around one piece persecond. In order to ensure a perfect thread rolling process, it is important for blank of work piece to beproperly pre-machined. The size of the blank is dependent on material, surface finish, type of threadsetc. This paper describes the effect of blank material and dimensions on nominal diameter of externalrolled threads. The work has been carried out at M/s Gayatri Auto Industries on Master ReciprocatingDies Thread Rolling Machine using HSS die. Mild Steel (C 15), EN-8 (C40), and EN-47 (SpringSteel) materials have been taken as blank material for the analysis to produce M8x1.25 6g threads.The result indicates that the variation on surface roughness, carbon percentage and dimension of blankaffects significantly the nominal diameter and PCD of threads. This paper is helpful for theprofessionals to determine the accurate dimension of thread rolling blank for desired threads tominimize rejections.
Evaluation of the Effect of Application of Air Jet Cooling and Cooled-Air Jet Cooling on Machining Characteristics of St 60 Steel
Authors: Rusnaldy Rusnaldy , Iskandar Norman , Umardani Yusuf , Paryanto Paryanto , Widyanto Susilo Adi
Published: January 2014

The use of cutting fluid is to reduce the friction between tool and workpiece, reduce and dissipate generated heat. The application of cutting fluid is also to improve the surface quality of workpiece and increase the tool life. On the other side, cutting fluid contains chemical carcinogens that causes serious health risks for machine operators and have inherent waste disposal concern on the environment. Due to these problems, some alternative have been sought to minimize or avoid the use of cutting fluid in machining processes. Air cooling techniques were proposed as alternative cooling mediums, i.e air jet cooling (AJC) and cooled-air jet cooling (CAJC), the liquid less method. In this work, air cooling techniques were investigated to be a possible solution of machining problem for cooling medium. This studi was also motivated by economics point of view that the application of AJC and CAJC would be more efficient than liquid method. The purpose of this study is to investigate the effect of AJC and CAJC on turning process of St 60 steel because it is used widely for production of components especially in small and medium enterprises in Indonesia. The tool tip temperatures, surface roughness and tool wear were measured for a range of cutting times. For a comparison purposes, experiments were also carried out with using traditional liquid coolant and without any cooling applied to the tool tip (dry cutting method). Experiments have shown that air cooling technques (AJC, and CAJC) can be used as cooling medium in machining process. Experimental results show that machining with CAJC have shorter tool life compare to machining with AJC and dry cutting, but liquid coolant in this studi is still the best cooling medium for machining of St 60 steel..
Organizational Culture in Manufacturing Company: Study Case of Small and Medium Sized Enterprises in Central Java, Indonesia
Authors: Lestari Hanna , Ismail Rifky , Mansur Agus
Published: January 2014

This paper discuss the organizational culture in metal manufacturing company which is classified as small and medium sized enterprises (SME) located in Central Java Province, Indonesia. This study is conducted to observe the action of the SME, especially for metal manufacturing company to face the regional free trade agreement in South-East Asia as a consequence of global market. The organizational culture is classified based on the internal factor, external factor, stability and control and flexibility and discretion. Four companies are involved in this study, where Company A, B and C are classified as small enterprises and Company D is classified as medium enterprise. The results described that the organizational culture is adhocracy for Company A, market for Company B and Company D and hierarchy for Company C. The adhocracy cultured company is predicted to be survived in ACFTA due to their innovative, customized and unique metal product and also specific customer. The medium enterprises is predicted to survive in ACFTA era due to their strong organizational structure, focused future plan, product diversification and measured product quality and standardization. The organizational culture for SMEs which is predicted to be suitable in winning ACFTA competition is adhocracy and market and supported by the product innovation, diversification and quality control. Mechanical and industrial engineers from university should takes place in assisting and supporting SMEs to win the competition in ACFTA era.
Development Machining of Titanium Alloys: A Review
Authors: Darsin Mahros , Basuki Hari Arbiantara
Published: January 2014

Titanium and its alloys are hard materials, wear resistant, high strength to weight ratio. Therefore this material become very promising, especially in aerospace application. However, its application restrict when face machining processes. This material is very hard which is very difficult to manufacture by machining. Its low Youngs modulus tends to springy and creates vibration or chatter. Moreover, it has low heat dissipation rate that make the heat concentrate in the tool tip especially in the friction surface between tool and chip. Those phenomena result in very low tool life and low quality of machined surface, in term of surface roughness, surface integrity. This article describes some efforts to overcome those problems. Categorically, there are some groups of effort, i.e. varying machining parameters, modification the tool, treatment of the material, and different method of applying the coolant. It seems that using cryogenic cooling upon the tool is the most promising new technology to machine the titanium alloy.
Application of Semi Automatic Model of Product Complexity Index Calculation by Identification and Recognition of Geometric Features Information
Authors: Budiono Hendri D.S. , Sholeh Mochammad , Kiswanto Gandjar , Soemardi Tresna P.
Published: January 2014

It is a phenomenon that an experience mechanical/ design engineer with years of experience in mechanical parts design, still must to improve the knowledge about process design. This phenomenon will be different with other fields but common in process design because design is continuous process. The automotive industry is expected to be one of the driving factors for economic growth in Indonesia in 2025. It is shown by research firm (Frost & Sullivan) that estimates this year's car sales in Indonesia will rise moderately by 6.5% from a year earlier to 948,500 units and the real car sales in Indonesia rose to 43% in April 2012. Development should be increased because the government provides to industrial facilities that conduct research, development and innovation. Therefore the design process until production is expected to be rapid and immediate product can be enjoyed by society. To speed up the production process, the design process should be faster, and account how the next process that is the production. This research useds the form of the usual features carried with three machining processes are widely used in the world of mechanical component industries. The processes are turning (around 24.9% of machining process), milling (around 20.2% of machining process) and drilling (around 28.2% of machining process). The overall mean of the three processes around 73.3% of the portion of the machining process (survey conducted by PERA).
Design of Multi Gender Bicycle - As an Alternative Bike Design to Fulfill Appropriate Requirement for Urban Society in Indonesia
Authors: Batan I Made Londen , Hendarto Reinaldi
Published: January 2014

In the present work, a multi-gender bike, which can be used by men and women, was designed. The integrated design method is used to develop a bicycle frame. As a human transportation the frame is must be light, strong, and comfortable for rider. The frame of bicycle is built with the material of aluminum alloy T-6061 and is produced as prototype for a multi gender purpose. With 100 kg load the strength of material is calculated, and the result shows that the frame critical strength is smaller than material ultimate strength. The prototype was tested by 5 respondents who have an average weight of 68.2 kg, and height 169.4 cm. Pedal test is conducted with 5 level of speed such as 6, 8, 10, 12, and 14 mph in 6 minutes of cycling respectively. The paddle energy during cycling was determined. The results show that the paddle energy increase and follow the increasing of speed. However since 10 mph of speed the paddle energy tends to be fixed with average value of 40 kcal. Therefore the tension leg muscles before and after cycling is going together by increasing the speed. The RULA method is used for determining the ergonomic of multi-gender bicycle, and the result shows that the value of risk injury is 3, that mean the developed bike is ergonomic.
Effect of Cellulose Acetate Phthalate (CAP) on Characteristics and Morphology of Polysulfone/Cellulose Acetate Phthalate (PSf/CAP) Blend Membranes
Authors: Ali Asmadi , Yunus Rosli Mohd , Awang Mohamad , Johari Anwar , Mat Ramli
Published: January 2014

Polysulfone (PSf) membrane is catogorized as hydrophobic membrane that easily fouled during membrane operation process. The presence of second hydrophilic polymer which added into membrane casting solutions plays a crucial role in adjusting the membrane properties. This hydrophilic polymer was employed in hydrophobic polymer membranes in order to improve hydrophilicity and performance as well as formed antifouling ultrafiltration (UF) membranes. In this study, a hydrophilic polymer, cellulose acetate phthalate (CAP) was added into polysulfone (PSf) membrane casting solutions by blending technique to produce PSf/CAP blend membranes. Flat sheet asymmetric PSf/CAP blend membranes were prepared by wet phase inversion method. The results revealed that an increase in CAP increased the hydrophilicity properties of PSf/CAP blend membranes compared to pure PSf membrane. The significant changes in size and numbers of microvoids and macrovoids in the morphological structures of PSf/CAP blend membranes were due to CAP promote the instantaneous liquid-liquid demixing during phase inversion process.
Experimental Study of Impact on Carbon-Fiber-Epoxy Composite Wing Leading Edge Structure
Authors: Omar Nurihan , Aminanda Yulfian , Mohamed Ali Jaffar S.
Published: January 2014

This paper works on the curvature composite structure for wing leading edge application using fabric carbon/epoxy material subjected to impact loading. At first stage, rigid spherical projectile and elliptical panel with were used. The impact testing has been carried out by varying the radius of curvature, the thickness of the panel and different stacking sequence. The experimental results show the trend of specific energy absorption capability of structure in function of the radius, thickness of panel and carbon fiber directions.
Comparison of AISI 316L Plasma Nitriding Behavior in Low and Medium Temperature
Authors: Istiroyah Istiroyah , Wardana I.N.G. , Santjojo D.J.
Published: January 2014

Plasma nitriding is a widely used technique to improve the mechanical properties and tribological properties of AISI 316L steel because it has many advantages over other surface treatment techniques. One of this advantage is plasma nitriding allows nitrogen introduce to steel at low temperature (below 500°C).In this study, nitriding of an AISI 316L was performed in high density plasma nitriding system using 70%N2:30%H2 gas mixture at 400°C and 480°C for 2, 4, and 8 hours. Optical Emission Spectroscopy (OES) with optical probe was used for plasma diagnosis. The properties of nitrided sample were investigated through microhardness measurement. The results show that N2 ions and radicals are species predominantly formed in plasma.
Development and Evaluation of Nano Electret Filters for Household Water Treatment
Authors: Ahn Young Chull , Cho Jae Ik , Kim Si Eun , Jeong Ah Hee , Kim Gil Tae
Published: January 2014

Korea is expected to one of countries with water shortages, and thus must secure high-quality water resources and strictly maintain them. However, water is frequently polluted and there is still a lack of water treatment technologies and facilities to provide safe water. To remove pollutants, membrane-based methods are being widely used for water treatment. It needs high pressure and energy to capture the pollutants by pore size. In this study, electrostatic force is used to increase the efficiency of filtration and decrease pressure loss. By electro spinning, nanoelectret filter is made with 100 nm in diameter and positive charge potential. Surface potential is measured by electrostatic voltmeter system with nanoelectret filter by three conditions of applied voltage. For the filtration performance, filtration efficiency is measured by filter test system with 0.5 and 1.0 PSL. Also pressure loss of nanoelectret filter is measured by comparing PC membrane.
Effect of Heat Treatment on Microstructure Homogeneity of Zn-3Mg Alloy
Authors: Dambatta M.S. , Izman Sudin , Hermawan Hendra , Kurniawan Denni
Published: January 2014

The Zn based alloy has a high potential to be the next generation of biodegradable implant material. Development of this biomaterial involves casting process which often associated with various defects. In this study, Zn-3Mg alloy was prepared using conventional casting method and followed by homogenization treatment (370°C for 10hr) with the aim to improve the microstructure uniformity. Microscopic images show that as-cast Zn-3Mg alloy consists of segregated Zn-rich structure of star-like dendritic shape and eutectic mixture of Mg2Zn11 phase. It is observed that after the heat treatment process thissegregation has been dispersed well and results in a more uniform microstructure of Zn-3Mg alloy with low fraction of casting defects.
The Optimization of the Technological Process with the Fuzzy Regression
Authors: Pietraszek Jacek , Skrzypczak-Pietraszek Ewa
Published: January 2014

The paper contains: problem definition, presentation of the measured data and the final analysis with the fuzzy regression approach. The benefits of such approach are shown in the case of small size samples. Both mentioned technological processes, the one from the automotive industry and the second from the biotechnological industry, have shown the significant benefits of using the fuzzy regression. In the case of small sample size problem, the results obtained from the fuzzy regression have significantly narrower spread in the comparison with the traditional confidence interval being very wide. The approach should also be useful for similar studies, when the probabilistic description of uncertainty is not possible for the reason of the time, the equipment or the financial limits. The developed method will be useful in eventual transition of the process from a laboratory scale to an industrial scale.
Enhancing Safety and Security of Networked FPGA-Based Embedded Systems
Authors: Osocha Przemysław
Published: January 2014

Embedded systems are supporting our society in more and more ways, replacing former mechanical and manual solutions and also assist us in absolutely new situations. They become indispensable to our civilization, therefore their correct and secure services are of utmost importance. But the new phenomenon of global networking rises another treat to our safety. Embedded systems are interconnected in a world-wide network and compromising security of single device may impact safety of bigger system. This paper discusses influence of security on safety of system of systems, and presents researches on FPGA-based embedded systems which may resolve some of posed issues.
Model of Fatigue Damage Accumulation
Authors: Drewniak Józef , Rysiński Jacek
Published: January 2014

In this paper, the analytical method of fatigue life estimation of gear teeth is proposed. The computational model of fatigue damage accumulation was built using the adequate NASGRO 2/3 formula, moreover Formans and Paris-Erdogans laws were utilized for comparison. The ranges of stress intensity factor were determined using the boundary element method.
Dual-Specificity Phosphatase 14 (DUSP14/MKP6) Negatively Regulates TCR Signaling by Inhibiting TAB1 Activation
Authors: Yang Chia-Yu , Li Ju-Pi , Chiu Li-Li , Lan Joung-Liang , Chen Der-Yuan , Chuang Huai-Chia , Huang Ching-Yu , Tan Tse-Hua
Published: January 2014

T cell activation is dependent upon phosphorylation of MAPKs, which play a critical role in the regulation of immune responses. Dual-specificity phosphatase 14 (DUSP14; also known as MKP6) is classified as a MAPK phosphatase. The in vivo functions of DUSP14 remain unclear. Thus, we generated DUSP14-deficient mice and characterized the roles of DUSP14 in T cell activation and immune responses. DUSP14 deficiency in T cells resulted in enhanced T cell proliferation and increased cytokine production upon T cell activation. DUSP14 directly interacted with TGF-β–activated kinase 1 (TAK1)-binding protein 1 (TAB1) and dephosphorylated TAB1 at Ser438, leading to TAB1–TAK1 complex inactivation in T cells. The phosphorylation levels of the TAB1–TAK1 complex and its downstream molecules, including JNK and IκB kinase, were enhanced in DUSP14-deficient T cells upon stimulation. The enhanced JNK and IκB kinase activation in DUSP14-deficient T cells was attenuated by TAB1 short hairpin RNA knockdown. Consistent with that, DUSP14-deficient mice exhibited enhanced immune responses and were more susceptible to experimental autoimmune encephalomyelitis induction. Thus, DUSP14 negatively regulates TCR signaling and immune responses by inhibiting TAB1 activation.
Autoimmune Vitiligo Does Not Require the Ongoing Priming of Naive CD8 T Cells for Disease Progression or Associated Protection against Melanoma
Authors: Byrne Katelyn T. , Zhang Peisheng , Steinberg Shannon M. , Turk Mary Jo
Published: January 2014

Vitiligo is a CD8 T cell–mediated autoimmune disease that has been shown to promote the longevity of memory T cell responses to melanoma. However, mechanisms whereby melanocyte/melanoma Ag-specific T cell responses are perpetuated in the context of vitiligo are not well understood. These studies investigate the possible phenomenon of naive T cell priming in hosts with melanoma-initiated, self-perpetuating, autoimmune vitiligo. Using naive pmel (gp10025–33–specific) transgenic CD8 T cells, we demonstrate that autoimmune melanocyte destruction induces naive T cell proliferation in skin-draining lymph nodes, in an Ag-dependent fashion. These pmel T cells upregulate expression of CD44, P-selectin ligand, and granzyme B. However, they do not downregulate CD62L, nor do they acquire the ability to produce IFN-γ, indicating a lack of functional priming. Accordingly, adult thymectomized mice exhibit no reduction in the severity or kinetics of depigmentation or long-lived protection against melanoma, indicating that the continual priming of naive T cells is not required for vitiligo or its associated antitumor immunity. Despite this, depletion of CD4 T cells during the course of vitiligo rescues the priming of naive pmel T cells that are capable of producing IFN-γ and persisting as memory, suggesting an ongoing and dominant mechanism of suppression by regulatory T cells. This work reveals the complex regulation of self-reactive CD8 T cells in vitiligo and demonstrates the overall poorly immunogenic nature of this autoimmune disease setting.
Convective transport of very-short-lived bromocarbons to the stratosphere
Authors: Liang Q. , Atlas E. , Blake D. , Dorf M. , Pfeilsticker K. , Schauffler S.
Published: January 2014

Abstract. We use the NASA GEOS Chemistry Climate Model (GEOSCCM) to quantify the contribution of two most important brominated very short-lived substances (VSLS), bromoform (CHBr3) and dibromomethane (CH2Br2), to stratospheric bromine and its sensitivity to convection strength. Model simulations suggest that the most active transport of VSLS from the marine boundary layer through the tropopause occurs over the tropical Indian Ocean, the Western Pacific warm pool, and off the Pacific coast of Mexico. Together, convective lofting of CHBr3 and CH2Br2 and their degradation products supplies ∼8 ppt total bromine to the base of the Tropical Tropopause Layer (TTL, ∼150 hPa), similar to the amount of VSLS organic bromine available in the marine boundary layer (∼7.8–8.4 ppt) in the above active convective lofting regions. Of the total ∼8 ppt VSLS-originated bromine that enters the base of TTL at ∼150 hPa, half is in the form of source gas injection (SGI) and half as product gas injection (PGI). Only a small portion (< 10%) the VSLS-originated bromine is removed via wet scavenging in the TTL before reaching the lower stratosphere. On global and annual average, CHBr3 and CH2Br2, together, contribute ∼7.7 pptv to the present-day inorganic bromine in the stratosphere. However, varying model deep convection strength between maximum and minimum convection conditions can introduce a ∼2.6 pptv uncertainty in the contribution of VSLS to inorganic bromine in the stratosphere (BryVSLS). Contrary to the conventional wisdom, minimum convection condition leads to a larger BryVSLS as the reduced scavenging in soluble product gases, thus a significant increase in PGI (2–3 ppt), greatly exceeds the relative minor decrease in SGI (a few 10ths ppt).
Opportunistic feeding on various organic food sources by the cold-water coral Lophelia pertusa
Authors: Mueller C. E. , Larsson A. I. , Veuger B. , Middelburg J. J. , van Oevelen D.
Published: January 2014

Abstract. The ability of the cold-water coral Lophelia pertusa to exploit different food sources was investigated under standardized conditions in a flume. The tested food sources, dissolved organic matter (DOM, added as dissolved free amino acids), bacteria, algae, and zooplankton (Artemia) were deliberately enriched in 13C and 15N. The incorporation of 13C and 15N was traced into bulk tissue, fatty acids, hydrolysable amino acids, and the skeleton (13C only) of L. pertusa. Incorporation rates of carbon (ranging from 0.8–2.4 μg C g−1 DW d–1) and nitrogen (0.2–0.8 μg N g−1 DW d–1) into coral tissue did not differ significantly among food sources indicating an opportunistic feeding strategy. Although total food assimilation was comparable among sources, subsequent food processing was dependent on the type of food source ingested and recovery of assimilated C in tissue compounds ranged from 17% (algae) to 35% (Artemia). De novo synthesis of individual fatty acids by L. pertusa occurred in all treatments as indicated by the 13C enrichment of individual phospholipid-derived fatty acids (PLFAs) in the coral that were absent in the added food sources. This indicates that the coral might be less dependent on its diet as a source of specific fatty acids than expected, with direct consequences for the interpretation of in situ observations on coral nutrition based on lipid profiles.
In Search for Novel Sn2Co3S2-based Half-metal Ferromagnets
Authors: Pielnhofer Florian , Tragl Amadeus Samuel , Rothballer Jan , Weihrich Richard
Published: January 2014

Substitution effects on magnetism of shandite-type compounds have been studied by density functional theory. The decrease of the Fermi level in the novel half-metallic ferromagnet Sn2Co3S2 to higher maxima of the density of states was modeled for substitutions on the Co site by the 3d metals Fe, Mn and Cr due to a rigid band scheme. Spin-polarized energy hyper surfaces and densities of states are calculated for Sn2Co3S2, and experimentally not yet known Sn2Fe3S2, Sn2Mn3S2 and Sn2Cr3S2 with shandite-type structure. The stability of half-metallic ferromagnetic characteristics, Slater-Pauling behavior, and alternative metastable spin states are discussed.
Functionalized Pyrazoles as Agents in C–C Cross-Coupling Reactions
Authors: Pejic Marijana , Popp Sebastian , Bolte Michael , Wagner Matthias , Lerner Hans-Wolfram
Published: January 2014

The 1-tetrahydropyranyl-(THP-)protected pyrazoles 4-R-pz(THP) (R=pinacolatoboryl=Bpin (3a(THP)), Me3Si (4a(THP)), Me3Sn (5a(THP)), and 4-R-3,5-Ph2pz (R=Bpin (3b(THP)), Me3Si (4b(THP)), Me3Sn (5b(THP)) were obtained by the following syntheses: i) In a first step, 4-X-pz (X=Br (1a), I (2a)) and 4-X-3,5-Ph2pz (X=Br (1b), I (2b)) were reacted with 3,4-dihydro-2Hpyran (DHP) to give the related THP-protected bromo- or iodopyrazole derivatives. ii) In a second step these THP derivatives were metalated by treatment with nBuLi or iPrMgCl. Subsequent reactions of the THP-protected metallopyrazoles 4-M-pz(THP) and 4-M-3,5-Ph2pz(THP) (M=Li, MgBr) with Bpin(OiPr), Me3SiCl, and Me3SnCl yielded the pyrazole derivatives 3a(THP), 3b(THP), 4a(THP), 4b(THP), 5a(THP), and 5b(THP). In contrast to the stannylated pyrazoles 5a(THP) and 5b(THP), the corresponding borylated and silylated derivatives could be easily deprotected: treatment of 3a(THP), 3b(THP), and 4a(THP) with HCl yielded the parent pyrazoles 3a, 3b and 4a. The microwave-assisted C-C cross-coupling reactions of these pyrazoles with aryl halides were examined, e. g. Suzuki reactions of 3a with p-pentylphenylbromide, p-hexylphenylbromide, and p- (2-ethylhexyl)phenylbromide. Similar reactions were also performed with 1a, 1b, 2a, and 2b and aryl-substituted pinacolatoboranes or boronic acids. Crystals of 5b(THP) suitable for X-ray diffraction were grown (monoclinic P21/c) and their structure determined. The crystal structures of 1a·HBr (monoclinic P21/n), 1b (triclinic P̄1̄), (1c)2·HBr (monoclinic P2/c), 1c·HBr·(Br2)0.5 (triclinic P̄1̄), (2a)3·H2SO4 (triclinic P̄1̄), 3a (orthorhombic P212121), (3a)3·H2O (trigonal R3c), 3b (orthorhombic Pna21), and 4a (monoclinic Pc) reveal interesting hydrogen bonding networks.