bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Low Voltage Ride through of Coal-Fired Power Unit Auxiliary in Henan
Authors: Gao Kun , Zhang Zhe Nan , Zhu Quan Sheng , Yuan Liang
Published: December 2013

The electric power short circuit breakdown may cause low voltage blocking of frequency-converter giving rise to power unit shutdown accident,three typical coal-fired power units are selected to emulate calculations on low voltage ride ability with considering threephase short-circuit earthing fault, threephase short-circuit earthing fault by impedance, single-phase short-circuit earthing fault ,indicating that the short-circuit fault of the lines integrating into power system would result in the voltage of house-service busbar dropping off to 25%-85%,especially threephase short-circuit earthing fault in small operation mode attacks on power unit auxiliary at the most, therefore auxiliary demands complete and dependable low voltage ride through ability. and puts forward to some reform suggestes.
Stress Corrosion Analysis of Steam Generator Tube of Nuclear Power Plant by Finite Elements
Authors: Jiang Shuang , Cai Jun , Zhang J.W. , Wang Y.D.
Published: December 2013

The steam generator is operated under the pressure of 15.5MPa and the temperature 327°C. Under this working condition the junction of the heat transfer tube and tube-sheet is accident-prone areas of the steam generator. By using ANSYS to carry out a thermal structure coupling analysis on the junction, it is found that a large tensile stress along axial and tangential directions occurs on outer surface of the heat transfer tube and is located at the region of 2.0 mm to 6.0 mm high over the tube-sheet. The stress attributes to the rapidly change of temperature on the tube outer surface and leads to the stress corrosions.
Structural Evolution of Fe-50Al/WC Composite Powder During Mechanical Alloyed Process
Authors: Wang Hong Tao , Wang Ruo Yu , Chen Xiao , Bai Xiao Bo , Dong Zeng Xiang , Ji Gang Chang
Published: December 2013

In the present study, Fe-50at%Al/WC intermetallic matrix composite powder was produced through mechanical alloying (MA) followed by annealing treatment. The phase transformations, grain size, microstructure and thermal stability of the composite powder during milling and annealing treatment were studied. The results showed that a bcc Fe(Al) solid solution reinforced with nanoscale WC particles was formed through high-energy ball milling The grain size of Fe(Al) decreased and the lattice strain of Fe(Al) increased with increasing milling time. The as-milled Fe(Al)/WC composite powder had lamellar structure. The oxygen content of Fe(Al)/WC composite powder increased with increasing milling time. The phase transformation from Fe(Al) to Fe-Al intermetallic phases was related to the milling time of composite powder and could occure at temperature of 400°C.
A Study on Modified Model Predictive DPC of Rectifiers
Authors: Zhao Hui , Wang Biao , Wang Hong Jun , Yue You Jun
Published: December 2013

In this paper, we study a modified predictive direct power control scheme (P-DPC).This scheme which based on model predictive control (MPC) uses a discrete rectifier model to infer the predictive direct power control theme again, and selects the operating time of voltage vector and voltage vector to realize fixed switching frequency through setting the minimum power errors of each sampling period. This control scheme has a lower switching frequency compared to MP-DPC; and it is still simple and clear implemented in the stationary reference frame directly, meanwhile, it does not need PI controllers or voltage-oriented controllers compared to other developed control schemes. We make simulations using MATLAB. The result show the excellence of this novel predictive direct power control scheme through improving the switching frequency, current THD and active power and reactive power quality compared to MP-DPC and LUT-DPC.
Internal Wave Parameter Inversion at Malin Shelf Edge Based on the Nonlinear Schrödinger Equation
Authors: Li Xiao Yong , Wang Jing , Sun Mei Ling , Ma Rui Ling , Meng Jun Min
Published: December 2013

We established a deep-sea internal wave detection model based on the nonlinear Schrödinger (NLS) equation and Synthetic Aperture Radar (SAR) images, and applied the model to the Malin Shelf edge, located at UK Continental Shelf, west of Scotland, to retrieve internal wave parameters. We selected the SAR images of internal waves at Malin Shelf edge, combined NLS equation with the action spectrum balance equation and Bragg scattering model, retrieved the amplitudes and phase velocities of the internal waves at Malin Shelf edge, and compared these data with those retrieved by the model based on KdV equation and those observed at the same period. The results show that the error between the data retrieved by our model and the measured data is very small, while the difference between the data retrieved by the detection model based on KdV equation and the measured data is significant. In addition, the phase velocities, calculated in our model and the model based on KdV equation, are both close to the measured data. Consequently, our model is valid and more accurate for the parameter inversion of internal waves in deep-sea area.
Monitoring System of City Water Supply Pipe Network Based on Zigbee and GPRS
Authors: Gao Han Wen , Zhu Shu Xian , Zhu Xue Li
Published: December 2013

Nowadays, in order to secure supply and realize the energy and water saving, the monitoring automation has become a basic need for the city water supply pipe network. A remote wireless monitoring system is proposed for the city water supply pipe network based on Zigbee and GPRS. The Zigbee nodes are mainly used to detect and gather information and data of city water supply pipe network. The GPRS is used to upload information to monitoring center and download orders to coordinators. No wiring necessary, which makes the system very convenient.
On-Site Identification of Zero Resistance Insulator Based on Infrared Thermal Image and Weights-Direct-Determination Neural Network
Authors: Li Tang Bing , Gong Lei , Yao Jian Gang , Kuang Yan Jun , Rao Bin Bin
Published: December 2013

A method using infrared thermal images and weights-direct-determination neural network (WDDNN) to identify the zero resistance insulators on-site is presented. The basic procedures were as follows: the infrared thermal image were denoised, intensified, segmented, and a rectangular which was regarded as object was intercepted in the insulators chain; in view of the relationship between gray value of infrared thermal images and temperature of object surface, four parameters which stand for standard deviation, absolute deviation, quartiles and range of gray value, were extracted directly; these four parameters were used as the input of WDDNN to train the model, which could be used identifing the zero resistance insulators after being trained. This method can effectively avoid the interference of transmission lines, and can meet the real-time require when identifying on-site. Experimental results verify the feasibility and effectiveness of this method.
Application of Numerical Simulation in Closed-Die Forging Forming for Universal Joint Fork
Authors: Yang Jin , Wang Ping
Published: December 2013

A universal joint fork is one of the key parts of the automotive and tractor drive shaft system, which needs high requirements in dimensional accuracy and product quality. In this study, the numerical simulation analysis of closed-die forging of the universal joint fork was carried out using the rigid-visco-plastic finite element model. In view of formation, heat transfer and heating generation coupled, the variation rules of forming load, stress field and strain field were obtained. The numerical simulation results show that good process parameters conditions can effectively control forming load, enhance metal flow and improve die life.
Discussion on Compensation Factor for Large-Radius Bending Die
Authors: Qian Xiao Lei , Liu Yi , Guo Rui , Zhang Yuan Qing , Wang Guo Qiang
Published: December 2013

For large-radius bending metal sheets with severe springback, an automatic compensation program based on APDL language was developed to achieve the ideal die geometry. To raise compensation efficiency, the range of the ideal compensation factor based on one-step springback analysis was deduced, and tests prove that more iterations will be needed if compensation factor was beyond the range, and proper selection of compensation factor among the range can be conducive to high compensation efficiency.
Marine Engine Simulation System for Crew Operation Examination Based on Virtual Reality
Authors: Zhang Qiao Fen , Sun Jian Bo , Sun Cai Qin , Shi Cheng Jun
Published: December 2013

Aiming at the present deficiency of operation examination for marine engine, a simulation system of marine engine based on virtual reality is developed. In this paper, the virtual scene and 3D entity model of marine engine is constructed by 3DS MAX according to the actual situation of engine room and the specific operation requirements, and then the 3D model is driven by DirectX in the environment of Visual C++6.0 to achieve the functions of VR scene roaming, human-computer interaction and operation examination. The VR simulation system developed as a part of the whole marine engine simulator can supply an almost real environment for the crew operation examination, which will greatly improve the operation ability of crew, being of important significance for the reform of crew examination in China.
Research on the Simulation for Sheet Metal NC Incremental Forming
Authors: Zhu Hu , Li Nan , Ju Jin
Published: December 2013

In the sheet metal CNC incremental forming, the forming is realized by its tool's step by step and point by point extrusion movements along the pre-programmed contour tool path in the outline of the sheet part. Therefore, the correctness of the forming path used to control the tool's movement has a magnificent impact on the forming quality. And a NC incremental forming process simulation method which is used to verify the correctness is showed in this paper. Meanwhile the simulation software system is developed by using VC++ and OpenGL. The case study shows that the software system can be used in the verification of NC incremental forming path and the motion analysis of forming tool, and the software system runs steadily and reliably.
A Simulator for Power Battery Characteristics Based on Bi-Directional DC/DC Converter
Authors: Li Shan , Liu Shu Xi , Wu Bo
Published: December 2013

In this paper a design scheme is introduced about the simulation of Li-ion power battery discharging characteristics based on the architecture DSP + IPM module. It is described the building of Li-ion power battery circuit model, and the obtaining of the characteristic parameters of Li-ion battery. The discharging characteristic is implemented on bi-directional DC/DC converting circuit. The design of hardware and software is introduced and the experiment result is given.
The Application of ANSYS to Ultrasonic Cleaner Design
Authors: Zhang Guo Hua , Liu Shi Xuan , Qi Yong
Published: December 2013

With the development of modern mechanics methods and computer technology, some practical commercial finite element analysis software was introduced to the ultrasonic cleaner design. ANSYS software is a financial structure, fluid, electric field, magnetic field, the sound field analysis in one large general-purpose finite element analysis software can be used in many industrial fields. The basic operation of ANSYS was introduced. The simulation based on the ANSYS was applied in the design of ultrasonic cleaner successfully, which can improve work efficiency and shorten development period of ultrasonic cleaner.
Experiment Study on the Influencial Factors and Laws of KDP Crystal Surface Quality by Horizontal Fly Cutting
Authors: Guan Jia Liang , Zhu Li Li , Zhu Sheng Gen , Ma Xin Qiang
Published: December 2013

The influence of tool rake angle, feed rate and back cutting depth on the surface roughness and surface waviness of KDP crystal were studied when processing KDP crystal in the way of horizontal fly cutting. Comparing with the influence laws of vertical single point diamond fly cutting, we analyzed the respective advantages of the two kinds of cutting processing methods and summarized the similarities and differences of the influence rules that cutting parameters on surface quality under the two ways.
Dimensional Synthesis of a 4-DOF Hybrid Driving Platform
Authors: Hong Zhen Yu , Zhang Zhi Xu , Xu Zhi Hua
Published: December 2013

A novel 4-DOF hybrid driving platform of flight simulator is presented. Its main load born by a PU limb which composed of pneumatic support unit, so the driving force, the safety and the simulation performance are all improved. The simulation performance is proposed to be taken as the evaluating index. Dimensional optimization of the driving platform is studied with the aid of the characteristics of Rayleigh quotient and vector. The influence law of scale parameters to simulation performance and constraints is discussed through monotonic analysis and it is adopted to seek the optimal solution of the simulation performance. The effectiveness of the method is proved by the example.
The Structure Design and Parametric Study of Dynamic and Static Grinding Head
Authors: He Jian Yun , He Hong , Wang Qiang , Zhu Xiao Yi , Yu Yuan
Published: December 2013

Based on the second development platform of CAXA electronic board, using the object-oriented programming method and vc++6.0 as the second development language, combining with the user's actual production, the structure of dynamic and static grinding head has been analyzed and the parameters of dynamic and static grinding head have been determineed. A system with friendly interface, clear structure, convenient operation has been designed which can realize the structure parametric design of dynamic and static grinding head.
Study on Thermal Deformation of Machine Tool under Different Environment Temperature
Authors: Luo Fan Jie , Song Dan Lu , Li Zhi Wei , Jian Qing Yun
Published: December 2013

Taking XK5034 vertical milling machine as the research object, its thermal characteristic's finite element analysis has been carried out through the ANSYS. The front-end of the spindle mainly affects the machining accuracy of machine tool, so on the basis of the temperature field analysis, its thermal deformation was analyzed under different environment temperature, and the change rules between environment temperature and thermal deformation of the front of the spindle was also acquired. The results show that the influence of machine tool thermal deformation under different temperature is obvious.
Design and Development of a Evaporative Cooling System for Desktop Computers
Authors: Rui Cao , Lin Ruan , Bin Xiong
Published: December 2013

The authors designed a set of adherent self-circulation evaporative cooling system for a general desktop computer, and also tested its performance.The results show that: this cooling system can effectively dissipate heat of the CPU, the temperature will be kept below 50°C while operating at full load; For this application,we remove the fan of the CPU and achieve zero-noise and zero-power of computer equipment basically.
Query Expansion Associated with Clustering
Authors: Yin Jie , Xu Wei Ran
Published: December 2013

The aim of the system is to achieve query expansion. The method works combining clustering of hierarchical methods. Through the information proffered by a background document, doc_ID, concerning the initial query, a cluster containing doc_ID can be produced by hierarchical clustering. And the word co-occurrence information can be extracted from the candidate documents in this cluster. Compared with the content in doc_ID, the result of the experiment using the system shows an expected performance to develop expanded terms which are qualified to add to original query.
Rapid Location of LED Die Array Based on Cross Correlation in Frequency Domain
Authors: Li He Xi
Published: December 2013

A rapid template matching algorithm is used to locate l-emitting d (LED) die array on wafer planes in vision-based LED sorting or die-bonding system, the image of LED die array is first converted to binary image and is pre-processed through morphological operations such as dilation and erosion, and the cross correlation operation between LED die templatae and wafer image in frequency domain is implemented by using fast Fourier transform (FFT), and the pixel coordinates of all LED dies on the wafer plane can be determined at one time using the cross correlation in frequency domain (CCFD) instead of in spacial domain. Experimental results of LED die array measurement to a large-diameter LED wafer show that detection efficiency is far higher than conventional normalized cross-correlation (NCC) algorithm, and is only half of consumed time to compare with the sequential similarity detection algorithm (SSDA), the proposed CCFD algorithm can be used for rapid LED die array location in vision-baesd LED sorting or die-bonding machines.
The Design of Water Dispenser Remote Wireless Control System
Authors: Juan Song , Zeng Shi Xian , Zhao Zhen Duo , Wang Hai Yan
Published: December 2013

A type of water dispenser remote wireless control system which concludes remote user terminal and household electrical appliances control terminal, connected by Internet, is designed and studied. The system can achieve message transmitting and remote controlling with using embedded technology, Internet and single chip microcomputer. According to the improved circuit, the control message of the remote terminal transmitted by infrared module is receipted and processed by ARM processor with energy saving as the remote wireless control for water dispensers is achieved.
Windows High-Speed Drawing Technology Research
Authors: Chou Zhen Dong
Published: December 2013

The display speed of image and large real-time data processing is a huge challenge for realtime system. This paper completed a thorough research on existing drawing technology on the platform of windows; analyzed adaptive characteristics of using the general high-speed drawing techniques for high speed drawing and its merits and demerits. Finally, through a lot of experiments and simulations of high speed drawing process after optimization and combination, tested their drawing performance and efficiency in order to select an appropriate drawing method to develop a high-speed graphics engine for large real-time data.
A Non-Uniform Regional Partition Coding of One Dimension Signal and its Application
Authors: Kintak U. , Xiong Gang Qiang , Tang Ze Sheng
Published: December 2013

In this paper, a novel method for one-dimension-signal coding based on non-uniform regional partition is proposed. A given 1D signal can automatically be partitioned into different regions with different lengths and the one-variable polynomial is used to do the Least Square Approximation for signal values in each sub-region. When the approximation error and initial partition are specified, a specific signal partition result is obtained. Based on this algorithm, an effective denoising scheme of 1D signal is implemented and some of the experimental examples are illustrated to prove that the quality of the re-constructed signal, the denoising effect are all satisfactory and can be referenced by other researchers.
Boundary Detection for Non-Ideal Iris Based on Gray Transform
Authors: Wan Hong Lin , Li Bao Sheng , Li Hong Sheng
Published: December 2013

Boundary localization is one of the key issues for reliable iris recognition system. For non-ideal iris images, eyelashes or eyelids occlusions and low contrast between iris and sclera will lead to inaccurate boundary localization. Specifically, if the intensive transition from iris to sclera is too smooth, outer boundary localization will be very difficult. To stress the problem, in this paper the boundary localization method is proposed in which nonlinear gray transformation is innovated in outer boundary localization process. The experimental results depict that our algorithm have improved the localization accuracy for non-ideal iris compared to the classical algorithms.
Method for CCD Edge Signal Processing
Authors: Xu Guo Sheng
Published: December 2013

In order to improve the measuring precision of the one-dimension line-matrix CCD, a new sub-pixel edge detection method is proposed. Firstly the date collected by the line-matrix CCD is converted to digital data by virtual oscillograph. Base on threshold comparison, the fitting part of the edge signal is picked up for further processing; secondly, the pixels are expanded following the edge direction of the edge point, and the edge signal is fitted through the two order multinomial; finally, comparing the two order curve with the threshold voltage through the least square fit method, the precise position of the edge point can achieve the sub-pixel edge location precision.
Complete Convergence of Generalized Pairwise NQD Sequences
Authors: Wang Hang , Tan Xi Li
Published: December 2013

In this paper, by the moment inequality of generalized pairwise negatively quadrant dependent (NQD) sequences, we prove the convergence of the generalized pairwise NQD sequences, which extend and improve the previous relevant results.
Design of Track-Mounted Drilling Rig Based on Wireless Remote Control System
Authors: Tian Hong Liang , Wang He Jian , Weng Yin Sheng , Wang Long Peng , Sun Dao Ming
Published: December 2013

In this paper, the development of the GDY-2000L type multi-function track-mounted engineering drilling rig is introduced, which emphasis on the hydraulic controlling system and wireless remote controlling system. Combined with the field test, it shows that the GDY-2000L type engineering rig can meet the demands of geological boreholes and geophysical blasting boreholes with complex conditions on the ground.
Research on Transient Force Decoupling Control of Hydraulic Shaking Table Based on Rapid Prototyping of DSP Algorithms Using SIMULINK
Authors: Sun Yan , Li Song , Fan Zhi Run
Published: December 2013

On the basis of theory analysis, deep research was made about the implementation of force decoupling control of hydraulic shaking table. Because tested specimen has eccentric and height, which produce flywheel moment and overturning moment, and causes the non-synchronization of every exciter, so transient force decouple control (TFDC) strategy is introduced in order to remove this effect. Then, the control strategy was realized based on DSP rapid prototyping. TMS320C2812 DSP was applied to acquire the analogue and digital; TMS320C6713 DSP was used to operate and communicate with embedded processor S3C2410 by dual-RAM in order to improve real-time and rapidity. In the end, this paper presents the implementation of a rapid prototyping control system, which involves the design of DSP algorithms using MATLAB Simulink blocksets, automated code generation in the CCS integrated development environment, and downloading the executable code to the Texas Instruments TMS320C2812 and TMS320C6713.
A Novel Design of a Hybrid Electronic Vehicle Based on Programmable Logic Controller
Authors: Li Yin Ying
Published: December 2013

This paper is to review the research trend of Hybrid Electronic Vehicle (HEV) and present a novel design of a HEV based on programmable logic controller (PLC).Since a hybrid vehicle can be at one of five status: Pure Electric Drive, Pure Engine Drive, Parallel Drive, Engine Drive and Electric Power Generation, and Brake for Energy Feedback, this paper presents a design of a HEV controlled by PLC which is to optimize the energy flow according to the vehicle status and the AC permanent magnet synchronous motor. This research is based on anovel design on the transmission system including dual-clutch, transmission control box and planet-gear structure. Switching between the five statuses is automatically controlled by a PLC using the information from the transducers.
Adaptive Robust Control for Driving and Regenerative Braking of Electric Vehicle
Authors: Xu Long , Wang Jun Ping , Bai Yuan , Hu Gai Ling
Published: December 2013

The driving and braking energy recovery system of electric vehicle faces a lot of uncertainties, including the system parameters and the running environment uncertainties. An adaptive robust control (ARC) is presented in this paper to treat the problems including disturbance and parameter variation in the design of driving and regenerative braking controller. It can enhance the stability robustness and performance robustness. A model of the driving and regenerative braking system is constructed and then the ARC controller is designed. The experiment results show that the controller based on ARC theory has better performance of stability, robustness, and disturbance attenuation than traditional PID controller.
Thermal Analysis and Failure Behavior of 8YSZ Thermal Barrier Coatings under Thermal Cycling Tests
Authors: Lu Guan Xiong , Hao Li Jun , Ye Fu Xing
Published: December 2013

In this study, thermal analysis and thermal shock test of 8wt.% yttria stablized zirconia (8YSZ) thermal barrier coatings (TBCs) on low heat rejection (LHR) diesel engine have been conducted. The influence of TBCs on temperature distribution of piston was discussed by employing ANSYS codes. The thermal shock resistance test was carried out by placing the samples under flame jet heating and compressed air cooling in turn. Two kinds of thermal cycling modes with different periods were used to investigate the role of cycling frequency in coatings failure. As the frequency rose, the service life of coatings significantly decreased. The spallation of coatings happened at the interface between bond coat and substrate. The stress calculation results indicated that considerable stress caused by thermal mismatch was one of the main reasons for TBCs failure. The heat affected zone (HAZ) under the bond coat inhibited the diffusion between the bond coat and substrate. The oxide layer consisting of Mg and Al oxides under the HAZ was harmful to the bond between bond coat and substrate, which was another main reason for the spallation of coatings.
Research on the System of Radio Frequency Identification and Localization Works in Microwave
Authors: Pan Yong , Hou Zi Ye , Xiong Jiang , Liu Kai Hua
Published: December 2013

Radio frequency identification and localization is a key technology in the Internet of Things. This paper reports an ARM Cortex-M3 processor based hand-held radio frequency identification and localization terminal and a 8051 processor based active radio frequency tags. The terminal and the tags utilize STM32F103VET6 and the low power consumption STC12LE4052AD as their master controller, respectively. Both of them use Nordic nRF24L01 as their radio frequency identification module. The system works in 2.4GHz ISM microwave band and can read, write and locate radio frequency tags within 20m indoors. The actual measurement of active radio frequency tags shows that this terminal is highly stable and comparable in 2.4GHz microwave frequency radio identification and localization.
Effect of Rare Earth Addition on Microstructure and Mechanical Properties of Al-Si Alloys: An Overview
Authors: Joy-Yii S.L. , Kurniawan Denni
Published: December 2013

This paper reviews the effect of rare earth addition on aluminium-silicon (Al-Si) alloys of hypoeutectic, eutectic, and hypereutectic types. The effects of rare earth on metallurgy, tensile strength, tensile fracture surface and wear behaviour of Al-Si alloys are highlighted and discussed in this paper. It was concluded that adding rare earth element to Al-Si alloys reduces the grain size of primary Si, increases the tensile strength and decreases the friction coefficient decreases. These indicate enhanced mechanical properties for rare earth modified Al-Si alloys are likely.
Influence of Carbon Concentrations in Reducing Co and Cr Ions Release in Cobalt Based Implant: A Preliminary Report
Authors: Mas-Ayu H. , Izman S. , Abdul Kadir Mohammed Rafiq , Daud Rosdi , Shah A. , Yusoff Mohd Faiz Mohd , Shamsiah M.W. , Yong T.M. , Kamarul T.
Published: December 2013

The releases of harmful ions from cobalt based alloy to host tissues have raised significant health concerns. Carbon contents in this alloy may influence ions release but has yet investigated. It is hypothesized that carbon contents in this alloy will help the formation of oxide layer during thermal oxidation process and hence reducing the release of Co/Cr ions after implantation. In this study, Co-Cr-Mo alloy with carbon concentrations of 0.03% and 0.24% were oxidized at 1050°C for 3 hours under atmospheric condition. The oxidized substrates were characterized under FESEM and subjected to circulating immersion test in simulated body fluid (SBF) for 21 days. Metal ions release was measured using inductively coupled plasma-mass spectrometry (ICP-MS) at day 0, 7, 14 and 21. Oxidized high carbon samples show denser and a more uniform oxide layer than samples with low carbon contents. It is found that compact oxide structure promotes less metal ions release during immersion.
Short-Term Breakdown in Silicone Rubber Based Nanocomposites Caused by Electrical Treeing
Authors: Jamil A.A.Abd. , Ahmad Mohd Hafizi Bin , Kamarol M. , Mariatti M. , Piah M.A.M.
Published: December 2013

This paper presents experimental study on short-term breakdown of silicone rubber based nanocomposites with different silicone dioxide (SiO2) nanofiller loading by focusing on the effect of electrical tree. The objective of this study was to investigate the ability of SiO2 nanofiller to inhibit the growth of electrical tree in silicone rubber until breakdown. Samples of silicone rubber based nanocomposites (three samples were filled with 1wt%, 2wt% and 3wt% of SiO2 respectively whereas the forth sample was unfilled silicone rubber), were used in this experimental study and two parameters such as electrical tree initiation voltage and breakdown time were measured. Based on the obtained results, the sample with the highest SiO2 loading has shown the highest tree initiation voltage and the longest breakdown time. Therefore, this makes SiO2 a promising material to be used as fillers in polymeric insulations for the purpose of retarding electrical tree growth.
Preliminary Work Towards Development of a Dynamic Job Shop Scheduling Model
Authors: Hussin Wan Nazdah Wan , Hassan Adnan , Halim A.H. , Zakaria Z.
Published: December 2013

This paper presents a preliminary work on a development of dynamic job shop scheduling model. The motivation of the study comes from an urgent need for practical procedures to enable easier and accurate feedback at operational level particularly related to job shop in small and medium-sized companies. A spreadsheet-based scheduling template is formulated and modeled using Microsoft Excel. A job shop benchmark case study available in OR-Library has been chosen to demonstrate the applicability of the basic model. The preliminary result indicating that the proposed spreadsheet model needs further refinement through incorporation of dynamic factors to be obtained from industrial practitioners.
Comparison of Different Scenarios Using Computer Simulation to Improve the Manufacturing System Productivity: Case Study
Authors: Zahraee Seyed Mojib , Hatami Milad , Rohani J.M. , Mihanzadeh H. , Haghighi Mohammadreza
Published: December 2013

In the manufacturing industry, managers and engineers are seeking to find methods in order to eliminate the common problems in manufacturing systems such as bottlenecks and waiting times. This is because that all of these kinds of problems impose extra cost to the companies. In addition, manufacturing companies are striving to sustain their competitiveness by improving productivity, efficiency and quality of manufacturing industry for instance high throughput and high resource utilization. The paper concentrates on the application of computer simulation to analysis manufacturing system in order to improve the productivity. Therefore, this study introduces a color manufacturing line as a case study and the basic application of arena 13.9 software. The goal of this paper is to improve the productivity and efficiency of the production line by using computer simulation. To achieve this goal, first the basic model of the current situation of production line was simulated. Second, three different alternatives were simulated and modified to find the best scenario based on the maximum productivity and minimum total cost.
Effects of Cutting Parameters on Hole Integrity when Drilling GFRP and HFRP Composites
Authors: Maoinser Mohd Azuwan , Ahmad Faiz , Sharif Safian
Published: December 2013

The demand for mechanical fastening in composite materials is increasing due to their potential in large assemblies, aerospace and automotive industries. In practice, small components are integrated into large assemblies drilling holes in composite materials. Drilling defect free holes in composite presents many challenges during part assembly and services. This study presents the effects of cutting parameters used for drilling holes in glass fiber reinforced polymeric (GFRP) composites and hybrid fiber reinforced polymeric (HFRP) composites. Both the composites plates of 3 mm thickness were fabricated using a hand lay-up technique for the purpose of evaluating the effects of parameters on the quality of drilled holes. The holes were drilled using a 5 mm solid carbide twist drill at different spindle speed and feed rate. The quality of holes was assessed with respect to damage factor (Fd) and surface roughness (Ra) of the drilled holes. Results showed that the HFRP composite experienced lower damage factor (Fd) as compared to GFRP composite at lower feed rate or spindle speed. Scanning electron microscopic (SEM) examination revealed that the occurrence of delamination, fiber pull-out and matrix cracking was accelerated in the drilled holes at high spindle speed and feed rate.
Effect of Drill Point Angle on Surface Integrity when Drilling Titanium Alloy
Authors: Murad Muhamad Nasir , Sharif Safian , Rahim Erween Abdul , Rival Rival
Published: December 2013

Surface integrity of machined component is of major importance for the reliability and safety requirements during in service especially for the aerospace applications. This paper presents an investigation on the effect of drill geometry on the surface integrity of drilled hole of Ti-6AL-4V during drilling operation. Drilling experiments were conducted under the MQL using a special vegetable oil known as Jatropha oil. Experimental results revealed that drill point angle and coolant-lubricant conditions significantly influence the surface integrity which include surface roughness, micorhardness and microstructure defects. The surface roughness decreased with greater drill point angle. The subsurface deformation layer thickness was approximately 9 - 15 μm from the top of the machined surface. Microhardness profiles of the last hole indicated that the subsurface deformation extend up to a 150 to 200 μm until it reaches to the average hardness.
Radiation Shielding Characteristics of Concretes Incorporates Different Waste Materials
Authors: Azeez Ali Basheer , Mohammed Kahtan S. , Al Bakri Abdullah Mohd Mustafa , Hasan Hana Ihsan
Published: December 2013

Samples of concrete incorporate different waste materials such as iron filings, iron balls of used ball bearings and slags from steel industry were assessed for their anti-radiation attenuation coefficient properties. The attenuation measurements were performed using gamma spectrometer of NaI (Tl) detector. The utilized radiation sources comprised Cs137and Co60radioactive elements with photon energies of o.662 MeV for Cs137and two1.17 and 1.33 MeV energy levels for the Co60. Likewise the mean free paths for the tested samples were obtained. The maximum linear attenuation coefficient values of 0.92±1.12×10-3for CS137and 1.12±1.57×10-3for CO60attained, in this study were for concrete incorporate iron filling wastes of 30 wt. %. The iron balls and the steel slags gave much inferior values. The concrete incorporates iron filings provided the best shielding effect. The microstructure, concretefillings composite density, the homogeneity and particulate distribution were examined and evaluated using different metallographic, microscopic and measurement facilities.
Enhance the Performance of Free Space Optical (FSO) Communication due to Atmospheric Turbulence via the Dual Diffuser Modulation (DDM)
Authors: Rahman Abdul Kram , Aljunid S.A. , Anuar M.S. , Fadhil H.A.
Published: December 2013

This paper focus on mitigating the atmospheric turbulence effect in free space optical communication using dual diffuser modulation (DDM) technique. Phase screen diffuser located on transmitter create 'new' beam wave to propagate through turbulence more efficiently. This technique uses two transmitter and differential mode detection at the receiver. The numerical result show that the DDM produce better performance compare to conventional FSO that using intensity modulation/direct detection (IM/DD) for On-Off Keying Modulation (OOK). The reduction in the scintillation level also improve in DDM compare to conventional technique that using a perfectly coherence beam.
A Study of Liberation and Separation Process of Metals from Printed Circuit Boards (PCBs) Scraps
Authors: Hashim Aimi Noorliyana , Zaheruddin Kasmuin Mohd , Kamarudin Hussin
Published: December 2013

Since the metallic elements are covered with or encapsulated by various plastic or ceramic materials on printed circuit boards (PCBs), a pre-treatment process allowing their liberation and separation is first needed in order to facilitate proficient extraction. In this work, a fundamental study has been carried out to recover metallic concentrates from PCBs scraps. The most important step is to separate or release particles from the associated gangue minerals at the possible liberation particle size. The samples of printed circuit boards were separated into the magnetic and non-magnetic fractions by Rare-earth Roll Magnetic Separator. Then, the magnetic and non-magnetic fractions were separated to heavy fraction (metallic elements) and light fraction (plastic) by Mozley Laboratory Table Separator. Results show that the unliberated particles still remain in the comminution fines PCBs. The use of Rare-earth roll magnetic separation was clarified that the Fe, Ni and Zn element tend to be condensed in magnetic particles. Meanwhile Cu element tends to be release in non-magnetic particles. Mozley Laboratory Table Separation was capable to obtain fractions with relatively high concentrations of metallic elements. This study is expected to provide useful data for the efficient physical separation of metallic components from printed circuit boards scraps.
Effect of Varying Mixed Refrigerant Composition on Main Cryogenic Heat Exchanger Performance
Authors: Zainal Abidin Mohd Zaki , Nour Usama Mohamed , Ku Shaari Ku Zilati
Published: December 2013

LNG plant requires a lot of energy for its production especially in liquefaction process. One of the reasons is due to inefficiency on some of its major equipments, particularly on Main Cryogenic Heat Exchanger (MCHE). The efficiency of this unit can be improved by the usage of Mixed Refrigerant (MR) which matches closely the heating curve between hot and cold stream. However, the study on this refrigerant is complex and tedious due to multi component refrigerant and phase changing process inside MCHE. In this study, effect of varying MR composition towards MCHE performance is analyzed, with focus on heat transfer coefficient in shell side of MCHE. The analysis was based on single and two phase flow conditions which are gas flow and liquid falling film flow. The adjustment of binary components in MR composition was studied for each flow regime. By doing this, the best composition adjustment that gives the highest value of heat transfer coefficient was determined. It was found that the adjustment of methane-propane (C1-C3) is the best arrangement for both cases. However, it needs to be tested by applying this to actual process condition, in this case by implementing it in simulated LNG process.
On the Bioremediation Potential of Inhabitant Microbes of Dredged Marine Soils: A Theoretical Framework
Authors: Anuar Nurasiah Mira , Mohd Kassim Angzzas Sari , Chan Chee Ming
Published: December 2013

Biological degradation is one of the most beneficial and economical methods to clean up contaminated marine soils. Although biodegradation by microorganisms encourages the natural process of contaminant removal and serve as potentially cost-effective treatment, limited facts in microbes and contaminant interactions lead in treatment failure. The present study had identified the existence of potential microbes in marine soils dredged from the coasts of Peninsular Malaysia. These included the genera ofSerratia, Vibrio, Enterobacter, andPseudomonas. Among these,VibrioandSerratiahave potential to degrade oil and grease as well as Polycyclic Aromatic Hydrocarbons (PAHs). Irrespective of any additions of particular nutrients, the existence of these genera whereupon reduces the potential for bioaugmentation treatment. Major problem in bioaugmentation is rapid decline in number of introduce microbes due to abiotic or biotic stress. The first stage needed to develop treatment strategies are by understanding the environmental conditions and factors that limit the ability of microbes to degrade the contaminants. Considering these understanding, biodegradation treatments of contaminated dredged marine soils is ease to design. This theoretical framework therefore aims to assess on the bacteria capability to degrade correlated with the contaminant concentration.
Ionic Liquid Polymeric Membrane: Synthesis, Characterization & Performance Evaluation
Authors: Mohshim Dzeti Farhah , Mukhtar Hilmi , Man Zakaria
Published: December 2013

Selected ionic liquids are known to enhance the absorption of CO2for CO2removal purpose. In the idea to improve the membrane separation performance for natural gas sweetening, ionic liquid modified polymeric membranes were fabricated by using polyethersulfone (PES) and blended with different composition of ionic liquid which are 5 wt% and 15 wt%. Each fabricated membranes were prepared and dried under solvent evaporation at 90°C. Dense structure observed from FESEM analysis indicated the miscible blends of ionic liquid and PES. TGA analysis showed all fabricated membranes are still containing solvent and this resembles that membrane drying period is still insufficient. All fabricated membranes were tested with ideal gas permeation test. From the result, the addition of ionic liquid has enhanced the ideal CO2pemeance about 150% as compared to pure PES membrane. The ideal CO2/CH4selectivity was also increase about 85% from the base but however, the separation index is still considered low and this may due to the presence of the solvent. This preliminary result has confirmed that the blending of ionic liquid with pure PES membrane has technically improved the membrane separation performance.
Performance Evaluation of Okra (Abelmoschus esculentus) as Coagulant for Turbidity Removal in Water Treatment
Authors: Fahmi Muhammad Ridwan , Hamidin Nasrul , Abidin Che Zulzikrami Azner , Umi Fazara M. Ali , Hatim M.D. Irfan
Published: December 2013

The objective of this study is to evaluate the performance of turbidity removal in water by using Okra (Abelmoschus esculentus) as natural coagulant. The coagulation active agent in various Okra sections was extracted with distilled water and NaCl 1.0 M solutions. Synthetic water containing kaolin with turbidity of 55 NTU was used as water source in this study. The result shows that Okra seed that extracted both with distilled water and NaCl 1.0 N solution has the potential advantage as natural coagulant for turbidity removal in comparison with other sections of the plant. However, the seed is not economically feasible to be used as coagulant. The dried Okras leaf that commonly considered as waste material could be proposed as an alternative coagulant in water treatment process, due to its similarity in coagulation behaviour with Okras seed. FTIR analysis on leaf shows that chemical functional groups in protein were significantly removed after extraction with distilled water and NaCl 1.0 N solution. The result indicated a strong correlation between the protein content and turbidity removal efficiency, which eventually suggest that the protein in Okra could potentially be an active agent in coagulation process.
Potential Use of Biofibers for Functional Immobilization of Lactobacillus rhamnosus NRRL 442
Authors: Shaharuddin Shahrulzaman , Muhamad Ida Idayu , Seng Kok Fook , Zahan Khairul Azly , Khairuddin Nozieana
Published: December 2013

The present study aimed to characterize the agricultural residues of sugarcane bagasse {SB} and pineapple core {PC} for the use in immobilization of Lactobacillus rhamnosus NRRL 442. Using Standard Official Methods, SB and PC were found to contain approximately equal amount of nutrition content. The nutrition contents found include: 2.7-2.8 % of protein, 9.8-10 % of crude fiber, and 0.3-0.5 % of fat. On the other hand, SB demonstrated relatively higher solution holding capacity of 9.42 ± 2.3 g/g dry size sample than that of 6.04 ± 2.1 g/g dry size sample in PC. Under screening electron microscope, the fiber of SB has a flat and even surface; in contrast, the fiber of PC has a rough and overlapping surface which may promote the attachment or cell holding capacity during the immobilization process. However, the viability tests after cells immobilization have shown that SB provided higher cell survivability of 93.6 % than that of 64.1% in PC. These result highlighted the greater role of solution holding capacity of cellulose in ensuring a better cell survivability after immobilization process. As conclusion, this study showed the near future potentiality of SB and PC as immobilization carriers for Lactobacillus rhamnosus NRRL 442. It may substitutes proportionally of raw materials and be functional feed for ruminant.
The Effect of Copigmentation on the Stability of Butterfly Pea Anthocyanins
Authors: Hassan Nor Diana , Muhamad Ida Idayu , Sarmidi Mohammad Roji
Published: December 2013

The objective of this research was to study the effects of co-pigmentation on the colour display and stability of Butterfly Pea extracts with plant extracts under different pH. The scopes of the work focus on the effect on co-pigmentation of the Cinnamon, Cumin and Turmeric extract on the colour display. The effects on colour enhancement and the stability of Butterfly Pea extract were evaluated. LC/MS/MS analysis shows that the anthocyanin in Butterfly Pea is highly acylated and therefore, is stable due to intramolecular copigmentation. The flavonoids content in Cinnamon extract was identified as Cinnamtannin B1(m/z 864.7, MW 864.7156) while in.Cumin extract, Apigenin 7-galacturonylglucoside (m/z 609.409, MW 608.524) and Luteolin 7-digalacturonide-4-glucoside (m/z 625.376, MW 624.376) were presented. Dimethoxycurcumin (m/z 394.2, MW 394.0134 and m/z 313.0, MW 312.975) was identified in Turmeric extract. Turmeric was suggested as the best copigment for Butterfly Pea since it showed the highest hyperchromic shift (61.41%), followed by Cinnamon extract (17.04%) and Cumin extract (16.08%).
Preparation and Characterization of Co-HA Powder Using Modified Electroless Method
Authors: Zaheruddin Kasmuin Mohd , Amin Sri Asliza Md , Rahmat Azmi B. , Jamaludin Shamsul Baharin , Khairel R.A.
Published: December 2013

C0-HA composite produced by simple electroless deposition method was studied. From the particle size analysis by Malvern particles analyzer its shows that 19% increment in average of the particle size powder increase after the electroless process with higher cobalt (II) chloride and reduction agent concentration. By EDX and XR-D analysis it was confirmed that cobalt metal was deposited onto HA and contribute to uniform distribution in morphologies by SEM analysis. The Vickers hardness result of up to 430HV was achieved after sintering process at 1250°C. The experimental results demonstrated that the Co-HA powder was successfully prepared by using this method and provide distinct advantages such as uniformity of deposition at lower cost and simple process.