bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Research of Foaming Concrete Performance with Different Ash Calcium
Authors: Gu Li Hua , Wang Yong Feng , Yue Jian Wei
Published: April 2013

Foam concrete as an inorganic building insulation materials, light weight, good thermal insulation and excellent fire performance characteristics, it is the new building materials with low flammability that is good for environmental protection, energy and money saving. This paper establishes the quantitative relationship between the foam concrete’s 3d, 7d and 28d compressive strength and ash calcium dosage through the comparative experiment and analysis. Reveales the law ash calcium on compressive strength, thermal conductivity and dry density of the foam concrete.
Research on the Super Rapid Strength Repairing Material Effects Resistance to Water Damage Performance of Cement Stabilized Macadam
Authors: Yang Jie , Li Jin
Published: April 2013

As the strength of the cement stabilized macadam forming requires sufficient long time, it seriously affects the service and maintenance of the road. This paper studies on early unconfined compressive strength and resistance to water damage properties of cement stabilized macadam mixing with super rapid strength repairing material. The results show that early unconfined compressive strength of cement stabilized macadam has been significantly improved through mixing with super rapid strength repairing material. This provides favorable condition to opening traffic quickly. In contrast to ordinary cement stabilized macadam, the resistance to hydrodynamic damage properties of super rapid strength cement stabilized macadam has been significantly improved，but no significant improvement in the softening coefficient.
Effects of Niobium and Titanium on the As-Cast Microstructure of Cr8Mo2VSi Cold Work Die Steel
Authors: Cao Jia Li , Chen Yin Li , Ding Ran , Han Yun
Published: April 2013

In this work, effects of Nb and Ti on the as-cast microstructure of Cr8Mo2VSi cold work die steel are investigated. It is found that the addition of Nb and Ti can effectively refine the dendrites of the steel to equiaxed grains. At the same time, the amount of Cr carbides has been reduced and the morphology of Cr carbides has been improved accompanied with the presence of multi-carbides containing a great amount of Nb, Ti and Mo. In addition, the phosphorous in the steel is moved from the grain boundaries into the multi-carbides.
Feasibility Study for Copper/Zirconium Oxides as Oxygen Carrier in Chemical Looping Air Separation (CLAS)
Authors: Wang Kun , Yu Qing Bo , Qin Qin , Li Jiu Chong
Published: April 2013

Chemical looping air separation (CLAS) is a new and energy saving method to separate oxygen from air. In this work, oxygen carrier was prepared by mechanical mixing method using CuO as active phase and ZrO2 as binder. XRD and SEM analysis indicate that ZrO2 cannot react with CuO at high sintering temperature and oxygen carriers prepared by this method are porous. Reactivity tests of oxygen carrier were investigated in STA409PC thermogravimetric analyzer using both temperature-programmed and isothermal thermogravimetry. The results show that the copper-based oxygen carrier has the capability of releasing oxygen when the temperatures higher than 850°C in nitrogen atmosphere. The reaction rates increase greatly as the temperature increases. Moreover, the oxygen carrier can keep high reactivity after several cycles. The copper/zirconium oxides as oxygen carrier were found to be suitable for CLAS process.
Research on Dynamic Recrystallization Behavior of 20CrMo Alloy Steel during Hot Deformation
Authors: He An , Chen Lin , Wang Shuo , Huangfu Le Xiao
Published: April 2013

Hot compression deformation test were conducted on 20CrMo alloy steel on a Gleeble-1500D thermal simulator when the deformation amount was 30%, temperature ranged from 1273 to 1373K and strain rate from 0.0015 to 0.015s-1. Flow stress curves were obtained under different deformation conditions; DRX activation energy was calculated using mathematical method. The starting time of DRX was analyzed and the kinetic equation of DRX was established. This model fits well with test data and can meet the requirement of engineering calculation.
Meshless Modeling of the Breakage Process of a Coal Prism within Vertical Roller Mills
Authors: Liu Yao Lu , Zhou Yuan De
Published: April 2013

This paper presents an investigation into the roll compression induced breakage process of a coal prism within a vertical roller mill. The targeted process was characterized by strong nonlinearities arisen from large deformation, and from original continuum to final discontinuum. A numerical approach coupling the Smoothed Particle Hydrodynamics (SPH) method and the finite element method (FEM) was developed for such a type of analysis. The SPH method was used to model a coal prism and its interaction with the mill structure, while the roller and the support table in the mill were modeled with the FEM. This computational model makes it possible to predict the deformation and progressive disintegration process in the coal prism, as well as the reaction force mobilized along the specimen-roller interface. Using a cubic coal specimen as an instance, the paper presents a preliminary numerical study under prescribed geometry and working conditions of a mill machine. Typical results of the breakage process as well as the development of contact force were provided and discussed.
Development and Application of Prediction Model for End-Point Manganese Content in Converter Based on Data from Sub-Lance
Authors: Zhang Bo , Xue Zheng Liang , Liu Ke , Xiao Wen Bin
Published: April 2013

Base on smelting data from converter sub-lance in a factory, the prediction models for end manganese content in converter were established by Multiple Linear Regression (MLR) and BP Neural Network (BP-NN) respectively. Prediction results showed that, MLR model was easy to set up, but could not accurately describe steelmaking process and its results were unsatisfactory, while BPNN model got more accurate prediction results for end manganese content in converter based on proper selection of model structure, adequate training using sample data and then correct determination of the weights. According to the spot tests, prediction relative error hit rate of 90.38% within ± 10% or 96.15% within ± 15%.
The Pozzolanic Activity of the Coal Gauge and its Evaluation
Authors: Chen Jie Yu , Sun Tao , Zhu Xiao Yan , Lei Xin Rong
Published: April 2013

The pozzolanic activity of the coal gauge obtained by thermal treatment is evaluated. X-ray diffraction and the compressive strength of the geopolymer prepared by the heated coal gauge are seen as the pozzolanic activity evaluation basis. The active alumina, degrees of dehydroxylation and the specific gravity of coal gauge at different temperature are measured. The results show that the pozzolanic activity of the coal gauge heated at 600°C for 4h is highest in the pozzolanic activity temperature range of 550-850°C and bad at lower 500°Cand higher 900°C. The degree of dehydroxylation, the active alumina and the specific gravity have great influence on the pozzolanic activity of calcined coal gauge. In the temperature range of the pozzolanic activity, the higher is the degree of dehydroxylation and the active alumina, the greater the pozzolanic activity is. The minimum is the specific gravity, the greater the pozzolanic activity is. So, the pozzolanic activity of the coal gauge can be evaluated approximatively by them.
Effect of Feedstock Type on Microstructure and Polarization of Plasma Sprayed LSM Cathode for Solid Oxide Fuel Cells
Authors: Wang Xiao Ming , Fang Chen , Zhu Zhou Can , Li Ning
Published: April 2013

Plasma spraying is employed to prepare porous La0.8Sr0.2MnO3 (LSM) cathode for solid oxide fuel cells (SOFCs) using both liquid suspension and solid feedstocks. The surface morphology and microstructure of the LSM deposits are characterized by SEM. The electrochemical behavior is investigated through the impedance spectroscopy. The specific surface resistance of 0.36 Ω•cm2 and 0.74 was obtained at 1000oC for SPS and APS LSM cathodes, respectively. The polarization of SPS LSM cathode is lower than APS LSM cathode by a factor of 2 to 2.4 in the temperature range from 850 to 1000 oC.
Separation Test of Copper-Zinc-Sulfur Mixed Concentrate in Kazakhstan
Authors: Pang Wen Hao , Liu Quan Jun , Ding Peng
Published: April 2013

The mixed concentrate which contains 9.97% Cu, 9.25% Zn and 38.62% S is selected from polymetallic sulfide ores in Kazakhstan. The difficulty of study is the effective separation of copper and zinc. We used the process of grinding the mixed concentrate, and then carried out separation flotation of copper, zinc and sulfur according to the properties of the mixed concentrate. Considering the poor effect of single depressant, we used the combination of zinc sulfate and sodium sulfite as the depressants for separating copper. The collector of copper floatation is 432-xanthate and the activator of zinc floatation is copper sulfate. As a result, we obtained satisfying selecting targets through closed-circuit test: The grade of copper is 21.91% and zinc is 6.95% in the copper concentrate. The copper recovery is 87.64%. The grade of zinc is 40.42% and recovery is 65.80% in zinc concentrate. The sulfur recovery is 46.39% in sulfur concentrate.
Study on the Surface Roughness of Titanium Alloy Machined by WEDM
Authors: Zhao Shu Guo , Li Rui , Yao Xiao Min
Published: April 2013

Due to the excellent characteristics of titanium alloy, was applied to aviation, marine, automotive, metallurgy, medical equipment and other fields. However, some of the characteristics make it machine difficultly, so the range of applications would be limited. In this paper, titanium alloy is cut by wire electrical discharge machining (WEDM) and study the surface finish. The model of surface roughness is established which is based on theoretical analysis. Experimental results were analyzed and optimized by the theory of signal-to-noise ratio and grey relational analysis (GRA) method. The minimal surface roughness is achieved by the optimal results .According to GRA, get the order that is the influence of electric parameters on the surface roughness.
Arbitrary Curvature Radius of the Optical Parts Precision Polishing Technology
Authors: Yang Mo , Guo Zhong Da , Yang Zhi Qiang
Published: April 2013

This paper puts forward a kind of magnetorheological polishing technology of arbitrary curvature radius spherical optical parts and the mechanical structure of its supporting equipment. By changing the position of the intersection point of the spindle unit and pendulum shaft device in the space, it can achieve high quality and rapid processing of an arbitrary curvature radius of the spherical optical parts. The wheel-head structure of our equipment is an endless belt structure. The magnetorheological fluids are added to the endless belt, and the wheel-head structure 15 is powered. Then, it will form a Bingham on the endless belt with which the surface of the processed optical parts contact. At last, it will achieve precision flexible polishing process ultimately. A simple mechanical structure design and breakthrough processing method are used in the equipment and the complete processing technology, which can achieve flexible polishing of large-diameter spherical (or plane) optical components with any radius. The machining accuracy is less than 1nm, achieving the requirements of the ultra-smooth surface.
Experiment Research on Preparation Pigment Type Magnetic Iron Oxide Powder Utilizing Magnetic Separated Slag
Authors: Cui Yu Yuan , Jiang Mao Fa , Shi Pei Yang , Liu Cheng Jun
Published: April 2013

This per systematically studies the influence of roasting temperature and time to the composition and performance of magnetic iron powder, with magnetic separated converter slag as raw material, and low-temperature roasting-magnetic separation craft is also used with analyzing methods of chemical, XRD, tinting strength and so on. The investigation reveals that: pigment type iron powder with high tinting strength and covering power can be prepared with magnetic separated converter slag. Iron content and tinting strength of the iron powder rise with reaction temperature, while the covering power tends to decrease. Tinting strength of the iron powder tends to rise with extending of reaction time, while covering power rises in the first and reduces afterward, with highest covering power of 56g•m-2 at reaction time of 30min.
Microstructure and Electrochemical Behavior of Sm0.5Sr0.5CoO3 Deposited by Solution Precursor Plasma Spraying
Authors: Wang Xiao Ming , Zhang Le Yi , Chen Ming Yan , Wang Lin Lin
Published: April 2013

Solution precursor plasma spraying (SPPS) was employed to prepare porous Sm0.5Sr0.5CoO3 (SSC) cathode for solid oxide fuel cell (SOFC). The surface and cross-sectional morphology of the SSC deposit were characterized by scanning electron microscopy. The effect of annealing on SSPS SSC microstructure was examined. The electrochemical behavior was investigated through the impedance spectroscopy. The results showed that the SPPS SSC cathode exhibits multidimensional porous microstructure. The electrochemical measurement result showed that the specific surface resistance of SSC decreased significantly with the increase of test temperature and yielded a specific surface resistance of 2.6 Ω•cm2 at 800oC.
The Controlled Powders Morphology of Bismuth Niobium Titanate Depending upon the Isothermal Annealing
Authors: Liu Xiao Chen , Li Bao Rang , Wang Li
Published: April 2013

In order to investigate the effect of isothermal annealing on the powder morphology, Bi3NbTiO9 powders were first synthesized by molten salt method and then calcinated at different temperatures for different dwelling time. The microstructure observation revealed that the crystal morphology of Bi3NbTiO9 powder changed greatly with the prolonged dwelling time. The powders started to change from cube to sphere in shape with the dwelling time prolonged to 240min and then became cube again as the dwelling time was prolonged beyond 360min at 850oC. In addition to a time-dependent particle evolution study, we explored primarily the original drive force of morphology transform from the viewpoint of dynamics.
Effect of Forced Convection on Grain Refinement of S32205 Duplex Stainless Steel
Authors: Chen Xiang Ru , Zhong Hong Gang , Song Chang Jiang , Zhai Qi Jie
Published: April 2013

The effects of forced convection on grain refinement of S32205 duplex stainless steel (DSS) were investigated using a continuous casting simulation setup. The sample, which was called slab simulating unit here, was solidified in the continuous casting simulation setup, whose temperature was controlled according to the cooling curve of a DSS slab center, with the bottom cooled by running water to simulate the solidification process of slab. Forced convection was generated by square-wave mechanical stirring. The CET (columnar to equiaxed transition) was gradually promoted by forced convection when the rotation of the crucible speeded up, the microstructure was refined significantly. The average columnar zone length was reduced from 8.2 cm to 4.8 cm, the equiaxed grain average size decreased from 9.5 mm to 1.7 mm, and the microstructure was refined from Widmänstatten plates to island-shaped pieces.
Characteristics of BiFeO3 Thin Films on a LaAlO3 Substrate by RF Sputtering
Authors: Cao Jian , Xing Jie , He Bin , Zhang Zi Yang , Duan Yan Ting , Gu Jiang Fan
Published: April 2013

In this paper, BiFeO3 (BFO) films were grown on LaAlO3 (LAO) substrate by a RF magnetron sputtering system. Fabrication parameters, such as work pressure, sputtering atmosphere, and post annealing were examined in terms of their influences on characteristics of the ferroelectric films. X-Ray diffraction, Raman scattering and scanning electron microscope measurements were employed to characterize the microstructure and the morphology of these films. At last, the ferroelectric characteristic of BFO has been studied, and the film has a large saturated polarization of 40 μC / cm2 under an applied field of 12 kV /cm.
Effect of Microalloying on Structures and Properties of Aluminum Alloy
Authors: Fei Zhang Ping , Huang Xin Min , Dai Rong Rong
Published: April 2013

The addition of alloy elements can improve the properties of aluminum alloy markedly. In the paper, three kinds of aluminum alloys were studied. By using SEM, EBSD and some other devices, the affects of microalloying elements on high strength and high conductivity aluminum alloy structure and properties were investigated.
3-D CFD Modeling the Straight Blade Vertical Axis Wind Turbine
Authors: Yang Qiu Ping , Galbraith Roderick , Xi De Ke
Published: April 2013

This paper use the Fluent software to calculate the flow field of the vertical axis wind turbine. The results got were almost agreeable with the experimental data. The results were much better agreeable with the experimental data when the TSR was larger than 1 .So it can be used as the fast and lower costing estimated tools for the vertical wind turbines.
The Design of the Mechanical Heart Valve by Using the Parametric Method
Authors: Zhang Yong , Wu Liang Liang , Zhou Feng , You Tian Xue , Wan Guo Jiang , Huang Nan
Published: April 2013

In order to reveal the design regularity for the various sizes of mechanical heart valve(MHV), the theoretical and parametric finite element method (FEM) were adopted to investigate the influence of the MHV pivot distance on the valve performance in this paper. Result shows that the characteristics of central flow can be improved for all sizes of valve with the increasing of the pivot distance, and the acceptable hydrodynamic performance of the MHV designed in this method was also shown in the valve pulsatile flow test, which proved that the parametric method is a useful tool for MHV design.
Application of Analytic Hierarchy Process in the Steel Industry
Authors: Liu Yang , Cheng Guo Ping
Published: April 2013

Through analysing the indexs of the steel industry supply chain financing default risk, the article establishes a multi-level fuzzy comprehensive evaluation model for the steel industry supply chain financing default risk. Application examples show that the model overcomes the defect of subjective evaluation. It’s a rational and effective tool to assess the default risk of the steel industry supply chain financing.
A Method to Measure the Station of Artificial Mechanical Heart Valves
Authors: Zhou Feng , Wu Liang Liang , Cui Yuan Yuan , Chen Ying , Yang Jie , Huang Nan
Published: April 2013

The experiments of artificial heart valves were divided into in vivo and in vitro experiments; in vivo experiments provide accurate experimental parameters serving in vitro research. Simulation experiment used in vitro usually goes like this, firstly design a similar model or prototype phenomenon, then analysis the model working out the regular parameters related to the process, ruled out the possibility of impact on the study of individual exist in vivo experiment. In vitro experiments are likely designed; performance can be simplified and prominently concerned about contents, even designed some extreme conditions to test. A number of means related to fluid experimental measurement are included, such as the Particle Image Velocimetry（PIV）[1], Dual Catheter Method [2]，and ultrasonic method[3] and so on. However, these methods have different kinds of limitations, for example the Dual Catheter Method cannot be used as a routine determination for clinic due to its destructiveness, and PIV test requires expensive equipment. This study was designed by the image processing technology of high-speed photography aiming at the production of a reliable, simple, economic, injury-free and non-contact measurement method.
Research on the Fuzzy Control for Vehicle Semi-Active Suspension
Authors: Hu Xiao Ming , Li Wan Li
Published: April 2013

The whole vehicle was divided into eight pieces for establishing the semi-active suspension vehicle mode. The different fuzzy control strategies were designed according to the vertical, heeling and pitching movement of vehicle body. The vertical, heeling and pitching comprehensive vibration of the vehicle were reduced by controlling the output current of the magneto-rheological damper. Simulation analysis was operated with the parameters of a certain type of vehicle, the simulation results show that the method using the fuzzy control strategy can well improve the vehicle riding comfortableness, and its effect is superior to the optimal control.
Analysis on the Incompleteness of Moral Hazard Model
Authors: Tang Yi Fang , Wang Ai He , Li Yan , Hu Yu Mei
Published: April 2013

Moral hazard model is an important model in contract design. Starting from the result set of the moral hazard contract, this paper analyzes the incompleteness of moral hazard contract which is with great practical significance. Our results show that if the contracting parties can’t reach a consensus on the possible outcomes of the future (i.e. the result set of contract), some efficiency contract (or agreement) may not be realized.
The Application Research of Six-Axis Force Sensor Used by Trans-Femoral Prosthesis
Authors: Xie Hua Long , Li Fei , Kang Guo Cun
Published: April 2013

Intelligent bionic leg (IBL) is an advanced trans-femoral prosthesis. First, the conception and structure component of IBL are introduced. Then, working principle of six-axis force sensor is analyzed in detail. The type selection and design of filter are discussed. In the end, the data filtering of low pass filter based on hamming window function is established and simulation is done. The simulation indicates that force and torque signal has a significant improvement after filtering and the filter designed in the paper is reasonable.
Research on the Relationship between the Transaction Cost and the Corporate Governance
Authors: Wang Gen , Chen Wei Yu
Published: April 2013

Since the transaction cost theory has been put forward by Coase, there is a wide range of applications in the externalities, the nature of the enterprise, the enterprise property rights, institutional change and economic development and reform, etc, however, the study of the applications in a single microscopic enterprise is relatively rare. This paper is based on a large amount reference, and puts forward that measure the efficiency of corporate governance from the Angle of transaction efficiency, provide a possible way for perfecting the governance structure of listed companies, which contains certain political meaning.
Mapping Matrix of Variable Cross-Section Roll Forming Based on Visual Detection
Authors: Sun Lu Ping , Qian Bo , Guan Yan Zhi
Published: April 2013

An image mapping algorithm is proposed to improve the precision of flexible roll forming. The mapping algorithm based on visual feedback and Image analysis technology. On-line detection device realizes image acquisition of cross-section profile. After processing and analysis, geometric feature is extracted by Hough transform in the image. Geometric feature is transformed to matrix which is built a mapping relation with the original matrix. The mapping algorithm describes the displacement and rotary error in the process of flexible roll forming. Closed loop control is realized by feeding back the error to the control system. Experiments results show that the mapping algorithm is a good algorithm for on-line dimensional precision detection in sheet metal forming.
Reconfigurable Control Software for Additive Manufacturing Machines
Authors: Liu Jie , Yang Yong Qiang , Lu Qing Hua
Published: April 2013

This paper presents a novel reconfigurable control software for Additive Manufacturing (AM) machines. At first, reconfigurable architecture is created based on the principle of layered manufacturing which all AM processes should follow. Then, the control software is designed aimed at providing consistent user experience for various AM machines. At last, the proposed control software is successfully applied to two different kinds of AM machines. Compared to the old control software on these machines, nearly 70% of functions are reused in the new one, which leads to a reduction of the research and development time eventually.
A Multi-Tip Turning Tool Structure for Thin and Long Pieces
Authors: Wang Song Hao , Chen Wei Bin
Published: April 2013

This paper presents the development of a Multi-Tip Tool Structure for fast turning process, to prolong overall tool life as well as to shorten machining time. Instead of one cutting edge in regular turning process, several cutting tools are used simultaneously in this assembly. With this arrangement, radial cutting forces are balanced with each other and the steady or follower rests in a regular lathe can be eliminated, for long and thin work pieces. Make the tooling structure more compact and more feasible for multi-head CNC turning or combo machining.
COM Component Based on Matlab Algorithm for Speckle Processing
Authors: Zhang Rong Lu , Yu Fu Sheng , Li Tao , Jiao Bin Bin , Du Gui Lin
Published: April 2013

As a non-contract optical measurement method in solid mechanics, the digital speckle correlation method (DSCM) has already been recognized as an excellent method for determining the surface deformation field in materials because of its outstanding features. In-plane displacement fields at the surface of objects under load are abstracted by using this method in this paper. And the corresponding maps of displacement fields are drawn to show deformation. The basic principle and mathematical model of gradient-based subpixel registration are briefly introduced for measuring subpixel displacement. COM component of this method is generated by using matlab7.1 through images of laser speckles. The COM component is called by Visual C++6.0 and the stand-alone application is generated. It is becoming easier to deal with image in Visual C++ by using this method. Then more time and energy will be spent on the algorithm. The development cycle of the algorithm is speeded up and efficiency of the application is improved.
Modeling, Analysis and Simulation of Bluetooth Process Based on SystemView
Authors: Chen Min
Published: April 2013

Bluetooth is a wireless system designed for short range connections of computing and telecommunication devices, aimed at cable replacement and personal networking. The main goal of this paper is to present a simulation environment for modeling interference based on frequency hopping spread spectrum and GFSK modulation. In this article, a complete structure of Bluetooth system model is established, and simulation procedures are given by applying SystemView, which is used as tool software for dynamic system simulation and performance analysis. In this context, the simulation model is used to emulate the Bluetooth process and analyze the results. The simulation model with SystemView could not only helps gain a better understanding of the basic principle and working modes of Bluetooth process, but also acts as a development platform for further research.
The Motor Fault Diagnosis Based on Neural Network and the Theory of D-S Evidence
Authors: Sun Chang Fei , Duan Zhi Shan , Yang Yang , Wang Miao , Hu Li Jie
Published: April 2013

In order to reduce the uncertainty of the traditional method that use a single parameter in the motor fault diagnosis, create a reliable motor fault diagnosis model by using multivariate information fusion technology and the combination of neural network and the theory of D-S evidence .First, fusion the information of many kinds of sensors, preliminary identify the modes of failure, find the information of different fault feature by analysing and processing data, establish the domain of feature. Then part diagnose the domain of feature by using neural network. The local diagnosis results form independent evidence body. Calculate the credibility of the fault distribution of each evidence body for recognition framework. It is difficult to discriminant fault types by directly using these reliability distribution. So choose appropriate D-S evidence formula to fusion each evidence body and further process and analyse the information of evidence. The credibility of the distribution is nearer and nearer to the judgement threshold value of fault types with one fusion, and the rest of the credibility distribution of the fault is more and more smaller. So the basic reliability distribution has better peak and separability, the diagnose results is more accurate, and finally achieve accurate diagnosis of the motor fault. The diagnosis example shows that the diagnosis method based on neural network and the theory of D-S evidence can realize comprehensive diagnosis of motor fault by using multi-resources information. The reliability and accuracy of this diagnosis method are far higher than that of the local diagnosis using single feature. It improves the precision of the motor fault diagnosis.
Effect of PTFE Retainer on Friction Coefficient in Polymer Thrust Bearings under Dry Contact
Authors: Mizobe Koshiro , Honda Takashi , Koike Hitonobu , Santos Edson Costa , Kashima Yuji , Kida Katsuyuki
Published: April 2013

Polyetheretherketone (PEEK) is a tough semi-crystalline thermoplastic polymer with excellent mechanical properties. While abilities of polyphenylenesulfide (PPS) are similar to PEEK, former material cost was lower than later. Polytetrafluoroethylene (PTFE) is well known because of its low friction coefficient and self lubrication ability. The objective of this study is to observe the friction coefficient of hybrid bearings, PTFE retainer sandwiched with PPS-races or PEEK-races. Rolling contact fatigue tests were performed and in situ friction forces wear measured. It is concluded that the PTFE retainer reduced friction coefficient.
Self-Learning of Robots and the Model of Hamiltonian Path with Fixed Number of Color Repetitions for Systems of Scenarios Creation
Authors: Gorbenko Anna , Popov Vladimir
Published: April 2013

In this paper, we propose a system of scenarios creation for self-learning of intelligent mobile robots. This model is based on the model of Hamiltonian path with fixed number of color repetitions for c-arc-colored digraphs. We show that the problem of Hamiltonian path with fixed number of color repetitions for c-arc-colored digraphs is NP-complete. We consider an approach to solve the problem. This approach is based on an explicit reduction from the problem to the satisfiability problem.
A Magnetic-Assistance System as a Super Finishing Following Turning Machining
Authors: Pa P.S.
Published: April 2013

A design system using a magnetic force with high efficiency to assist discharging dregs out of the electrode gap during the electrochemical finishing on the surface finish process that follows turning machining process is investigated in the current study. Through the equipment attachment, magnetic-assistance during electrochemical finishing can follow the turning process on the same machine. This process can be used for various turning operations. Among the factors affecting electrochemical finishing, the magnetic-assistance is primarily discussed. The experimental parameters are magnetic strength, distance between the two magnets, current rating, on/off period of pulsed current, feed rate of workpiece, and rotational speed of workpiece. A higher current rating with magnetic-assistance reduces the finishing time and avoids the difficulty of dreg discharge. Providing a large magnetic field intensity or using a small distance between the two magnets produces a larger magnetic force and discharge ability and better finishing. A large rotational speed of the workpiece and electrode produces better finishing. Pulsed direct current can slightly promote the effect of electrochemical finishing, but the current rating needs to be increased. The magnetic-assistance during the electrochemical finishing process makes a great contribution in a short time by making the surface of the workpiece smooth and bright.
Assessment of Shear Behaviors of a Web Panel with Free Lower Boundary
Authors: Ahn Jin Hee , Kainuma Shigenobu , Kim In Tae , Jeong Young Soo
Published: April 2013

Shear behaviors of a web panel are changed by web boundary conditions and web panel with free web boundary has been reported by severe corrosion damage. In this study, post shear buckling behaviors of web panel with free-lower web boundary was examined to evaluate its shear failures and strengths depending on its web boundary changed by corrosion. Thus, nonlinear finite element analyses were carried out to identify their post buckling behaviors. Their shear behaviors and shear failure mode were compared as well as comparisons of their behaviors depending on aspect ratio and boundary conditions.
Rigid-Body Contact Using Finite Particle Method
Authors: Yu Ying , Wu Ming
Published: April 2013

Using the recently proposed Finite Particle Method (FPM), this paper presents the rigid-body contact simulation of 3D structures. The FPM models the space truss with finite particles. Following Newton's second law, every particle is in a permanent dynamic equilibrium. Fictitious motion procedures are developed in the particle internal force calculation to handle the geometric nonlinearity without iterative correction. Contact model and corresponding algorithm are developed based on the FPM. A numerical example is presented to demonstrate the capability of the FPM for analyzing rigid-body contact problems.
Experimental Research on Performance Change Regularity of Road Asphalt with Multiple Aging and Regeneration
Authors: Liu Ping , Nie Yi Hua , Zhang Yun Long
Published: April 2013

Due to the use course limitation of asphalt pavement at home and abroad, research on road asphalt recycling is laid particular stress on an aging regeneration properties both in China and abroad at present, and research on multiple aging and regeneration is much less. In this paper, five heating tests of 40 min, 85 min, 180 min, 240 min, 300 min were carried on to simulate asphalt aging , and reentry another same time aging after regeneration for each aging asphalt, so reciprocating cycle five times, each group of sample use the same reclaiming agent to regenerate NO.70# road asphalt after every aging test. The experimental results show that: after aging regeneration many times, performance index of NO.70 road asphalt can return to no age level, namely the asphalt multiple recycling is completely feasible.
Non-Coaxial Plasticity Constitutive Modeling of Sands
Authors: Hu Ping , Huang Mao Song , Wu Deng Gao
Published: April 2013

Classical coaxial plasticity constitutive models implicate an inevitable limitation that directions for principal stress and that for principal plastic strain increment are always coaxial. They are not capable of simulating non-coaxial phenomena during the rotation of principal stress axis. In this paper, a three-dimensional, non-coaxial plasticity constitutive model for sands with a modification of Lade angle dependent shape function is introduced to describe the non-coaxial behavior under principal axes rotation. A series of numerical simulations of hollow cylindrical torsional shear tests are performed. The results show that the proposed constitutive model can predict the variations of principal plastic strain increment directions with principal stress directions reasonably.
Characterization of Plasmonic Silicon Solar Cells Using Indium Nanoparticles/TiO2 Space Layer Structure
Authors: Ho Wen Jeng , Lee Yi Yu , Chen Yuan Tsz
Published: April 2013

We demonstrate experimentally the enhanced performance of the plasmonic silicon solar cell by using a nano-sized indium-particles and different thickness of TiO2 space layer structure. The optical reflectance, dark and photo current-voltage, and external quantum efficiency are measured and compared at each stages of processing. The conversion efficiencies enhancing of 17.78%, 27.5% and of 47.85% are obtained as the solar cell with indium nanoparticles on a 10-nm, a 30-nm and a 59.5-nm thick TiO2 space layer, respectively, compared to the solar cell without coated a TiO2 layer. Furthermore, the plasmonics conversion efficiency depend on the thickness of space layer are also demonstrated that the increasing by 15.46%, 12.1% and 6.08% for the solar cells with a 10-nm, 30-nm and 59.5-nm thick TiO2 space layer, respectively, were obtained.
The Effect of Fly Ash on Lime Mortar on Elevated Temperature
Authors: Ghaffari Alireza , Ghaffari Amirreza
Published: April 2013

To enhance the mechanical and compressive strength of lime mortar(lime-sand ) the fly ash was added to the compound to improved the engineering performance of lime mixture .The addition of fly ash and lime stone dust to clay soils reduce their plasticity characteristics, swell potential and improve their compressive strength (Brooks et al. 2011) .Boardman et al (2001) observed that no significant pozzolonic activity appears to take place until 7 days of curing during their experiments at room temperature .In this research the effect of fly ash at different range from 30 to 70 percent of mix by varying lime percentage from 6 to 20 percent with thermodynamic parameters of their reaction was assessed in normal and raised temperature by curing compacted specimens in the laboratory .The compressive strength of fly ash and lime mixture are determined on curing period up to 28 days in normal state and one days on raised one .The Result portrayed that raised temperature highly boosted the compressive strength of the mix from 30 to 120 percent at different range of fly ash mixture with lime.
A Study on Hydrogen Sulphide as Potential Tracer in Landfill Gas Monitoring
Authors: Tengku Izhar Tengku Nuraiti , Mohd Odli Zaity Syazwani , Zakarya Irnis Azura , Mohd Saad Farah Naemah , Ibrahim Norlia Mohamad , Che Amat Roshazita , Binn Tan Ley
Published: April 2013

Municipal solid waste (MSW) landfills are one of the major source of hydrogen sulphide (H2S) which is the offensive odours potentially creating annoyance in adjacent communities. This project focuses on H2S emission from landfills in Perlis, Malaysia. Landfill gas (LFG) samples were collected and analyzed accordance with NIOSH method 6013. The mean concentrations of H2S in Kuala Perlis Landfill and Padang Siding Landfill are 210.68 ppm and 242.85 ppm respectively. High concentrations of H2S may be a concern for employees working on the landfill site. These results indicate that workers should use proper personal protection at landfill when involved in excavation, landfill gas collection, and refuse compaction. The formation of H2S most likely to be contributed by the biological conversion of sulfate from gypsum-rich soils and landfill wastewater treatment sludges by sulfate-reducing bacteria (SRB) which can utilize dissolved sulfate as an electron acceptor. H2S is conveniently detected by hand held analyzer, such Jerome meter, landfill gas analyzer. In the organic range, in the ease of detection range in the dispersion rate within the landfill site, the monitored H2S gas form a very noticeable concentration with the travelling wind direction. It proved that the dispersion rate of H2S are suitable as tracer to detect route of travelling in a certain distance.
Fabrication of ZnO Nanowall-Based Hydrogen Gas Nanosensor
Authors: Chen Tse Pu , Chang Sheng Po , Chang Shoou Jinn
Published: April 2013

Two-dimensional ZnO nanowalls were rapidly grown on glass substrate by thermal evaporation at low temperature without any catalysts or the pre-deposition of a ZnO seed layer on the substrate. Most of the ZnO nanowalls grown at 450°C were vertical on substrate and they were about 70-200 nm thick and 2 µm long. The room-temperature photoluminescence (PL) spectra showed a strong intrinsic ultraviolet (UV) emission and a weak defect-related emission. Hydrogen-sensing characteristics of the ZnO nanowalls have been investigated, and that make them become attractive candidates for gas sensor.
Study on the Technology for Underground Treatment of XingFu Mine Water
Authors: Wang Jia Ping , Mei Tao
Published: April 2013

According to the XingFu mine's water quality, put forward a technology for mine water underground treatment. Changing original underground mine water sump into complex settling pond. Estimate the investment and the operation cost of the underground mine water treatment project. The result shows that: the cost of the underground mine water treatment is only 1.1172 yuan per ton, saving about 2 yuan per ton compare with the price of industrial water. This prove that it is feasible and saving for underground mine water treatment in XingFu mine.
Research for Biodegradation and Bioaugmentation of Drilling Wastewater
Authors: Xu Feng , Gu Jin Chuan , Bao Jin
Published: April 2013

The paper studied the degradation rate of single strain, the microorganisms agent compatibility and the bioaugmentation effects of the activated sludge system. The results showed that 10 strains screened from drilling site were able to degrade drilling wastewater. Confirm the optimal ratio of strains’ compatibility through orthogonal experiment. In augmented experiments, it showed that in the control SBR system with the COD of the effluent was in three different average levels (with two load shock), the COD degradation rates were 21.4%, 22.8% and 6.9%. In the augmented system treated with the same effluent, the degradation rates of augmented system were 64.8%, 62.78% and 66.9% respectively. It showed that the activated sludge was augmented by the mixed cultures which made the system to be more stable and improve impact resistance.
The Application Analysis of Sprinkling and Drip Irrigation Technology in the Ecological Environment Construction
Authors: Li Fang Hong , Liang Xu Li , Chen Kang
Published: April 2013

To solve the problems in the construction of ecological environment, this paper studies the application, effect and investment of sprinkling irrigation and drip irrigation in the ecological environment construction by the field trials. The results show that the optimal irrigation technique for the restoration and reconstruction of ecological environment in desert area is the drip irrigation technique, followed by the point watering technology with portable hoses.
Analysis on Variation Characteristics of Precipitation Time Series in Weihe River Basin during the Past 55 Years
Authors: Wang Shuai , Lei Xiao Hui , Zhang Feng
Published: April 2013

By using linear regression, moving average, Mann-Kendall test and Morlet wavelet analysis method, the annual, flood seasonal and dry seasonal precipitation series during 1954~2008 in Weihe River basin are analyzed. The results indicate that: ①Annual precipitation and precipitation in flood season and dry season present decreasing trends during the past 55 years, and the variation trends are not significant. ②There is an irregular spatial distribution of mean annual precipitation, which shows a decreasing trend from southeast to northwest. ③Annual precipitation exists principal periods of about 2, 10, 17 and 50 years, and the phase changes of 2 and 50 years period are most obvious. Time scales of phase change of precipitation series in flood season and dry season are roughly consistent with those in annual. The research results will provide reference for climate analysis and future weather forecasting in Weihe River basin.
Optimizing and Analysis for the Microchannel Heat Sink of High-Power LED Array
Authors: Li Ru Chun , Zhang Xin , Zheng Qi
Published: April 2013

The high power light emitting diode (LED) array integrated with the microchannel heat sink is designed. Detailed theoretical analysis of the thermal resistance for the microchannel heat sink is obtained. The thermal resistance minimum is achieved by the heat sink structure optimization, the result of theoretical analysis is simulated by MATLAB software. The result shows that: the system acquired the best heat dissipation effect, when the total size of the radiator is fixed, the width of the cooling channel is 0.1mm, and the cooling water flow rate is 1 m/s, the minimum of thermal resistance is 0.019w/°C.
Photocurrent Enhancement between Two Coplanar Schottky-Barriers on Silicon MSM Photodetector
Authors: Atiwongsangthong Narin , Niemcharoen Surasak
Published: April 2013

Gain properties of dc and ac photocurrent generated between two Schottky barriers coplanarly placed on silicon metal-semiconductor-metal photodetector have been investigated experimentally. The test structure has two square Mo/n-Si Schottky barrier junctions on an n-type silicon substrate with a resistivity of 9-12 Ω-cm and the junction internal separation is 20 m. The current-voltage (I-V) characteristics under illumination in visible range showed a rapid increase in the photocurrent at higher bias region. From the I-V characteristics and noise measurements, increase in photocurrent was ascribed to avalanche multiplication of carriers photogenerated in the reverse-biased Schottky junction. From observation of optical signal demodulation at low frequencies (10 kHz and 50 kHz), it was found that multiplication factor larger than 100 at 10 kHz and 30 at 50 kHz was achieved respectively.
Two-Diode Model Analysis and Experimental Verification for Photovoltaic Cells
Authors: Shang Er Song , An Tao
Published: April 2013

This paper analyzed a kind of two-diode model and reasonably simplified the mathematical calculation process under different irradiance, proposing a method which can use maximum power point to calculate simultaneously series and parallel resistance. Two kinds of PV modules should be tested in order to validating the accuracy of the proposed method. It is calculated that the relative error of single diode model is 1.72% and the two-diode model is 0.45%. The result shows that more accuracy can be performed for two-diode model in reflecting the output characteristics of photovoltaic cells.
Influence of Annealing Atmosphere on the Characteristics of Sol-Gel Derived ITO Thin Films
Authors: Peng Yu Ming , Su Yan Kuin , Yang Ru Yuan
Published: April 2013

In this paper, the Indium Tin Oxide (ITO) thin ﬁlms were prepared by a sol-gel dip coating method and then annealed at 600°C under different atmosphere (vacuum, N2 and 96.25%N2+3.75%H2). Their microstructure, optical and electrical properties were investigated and discussed. Suitable atmosphere can improve the crystalline of the ITO films, therefore the optical and electrical properties of the ITO films are improved. The uv-vis results showed the maximum of transmittance in the visible range (380-780 nm) of 85.6% and the lowest resistivity of 4.4×10-2 Ω-cm when the ITO films were annealed under 96.25% N2 with 3.75% H2 atmosphere.
Generation of Dense Lying Ga(As)Sb Quantum Dots for Efficient Quantum Dot Lasers
Authors: Loeber Thomas Henning , Hein Eric Alexander , Hoffmann Dirk , Heisel Carina , Fouckhardt Henning
Published: April 2013

Two different approaches are pursued to realize densely packed gallium (arsenic) antimonide (Ga(As)Sb) quantum dots (QDs) for efficient QD lasers. In the first method nano¬structures are realized by self-organization using mask-less dry-etching. GaSb cone structures are achieved with a maximum density of 1.2 ∙ 1011 cm-2. During etching a 5 nm thick amor¬phous Ga layer is formed, also the surface oxidizes immediately under atmosphere, and as a consequence the dots are optoelectronically inactive, thus no photoluminescence (PL) can be achieved. Several attempts are made to revoke these effects, but the nanostructures stay inactive. In the second approach self-assembled optoelectronically active GaAsSb QDs are grown on GaAs in Stranski-Krastanov mode. With these QDs efficient lasers are grown, exemplarily with an emission wavelength around 900 nm. In pulsed mode a minimum thres¬hold current density of jth = 121.7 A/cm2 and a maximum in differential quantum effi¬ciency of ηd = 0.66 are measured at T = 130 K. The internal quantum efficiency is ηi = 0.76 with internal losses of αi = 4.86 cm-1.