bluuebunny/crossref_metadata_2025 huggingface dataset:
Território no mundo A’uwe Xavante
Authors: Gomide Maria Lucia Cereda
Published: March 2011

Este artigo tem objetivo de discutir a concepção de território e de territorialidade do povo A’uwe Xavante. O recorte geográfico desta pesquisa são as terras indígenas Xavante no leste do Mato Grosso, este povo, conta com população atual em torno de 14.000 pessoas, sendo distribuídas em nove Terras Indígenas (TI)  Sangradouro, São Marcos, Areões, Pimentel Barbosa. Parabubure, Chão Preto, Ubawawe, Marechal Rondon, Marãiwatsede. Marca histórica desse povo são as migrações pelos cerrados do centro-oeste, onde buscaram viver sem o contato com a sociedade envolvente, no entanto, com a ocupação da região pelo Estado brasileiro, principalmente com a ‘marcha para o oeste’ na década de 1930, faz com que o território indígena seja invadido e cercado, gerando sérios conflitos, o que levou à demarcação das terras indígenas Xavante nos anos 1970.Entende-se que a reprodução física e cultural dos povos indígenas em seus territórios, em grande parte está condicionada à demarcação de territórios indígenas, que considere a territorialidade e o modo de vida indígena. No entanto não foi o caso do território Xavante. A demarcação do território indígena Xavante em diversas terras indígenas ilhadas e, portanto, separadas entre si, causou inúmeros conflitos socioambientais alterando seu modo de vida. Reconstruir o território indígena que foi erroneamente e intencionalmente fragmentado e demarcado em ilhas é um grande desafio político para o povo Xavante. O território indígena compreende as relações de apropriação do espaço que possui diversas dimensões como política, cultural, simbólica, e cosmológica de um determinado povo indígena. Por outro lado, Terra indígena é uma categoria produzida no processo político-jurídico do Estado. Assim, a partir do contato entre os povos indígenas e a sociedade envolvente, há um conflito, pois existem distintas lógicas espaciais em confronto.
Políticas Territoriais e Mobilidade Populacional na Amazônia: contribuições sobre a área de influência das Hidrelétricas no Rio Madeira (Rondônia/Brasil)
Authors: Cavalcante Maria Madalena de A. , Nunes Dorisvalder Dia , Silva Ricardo Gilson da Costa , Lobato Luiz Cleyton Holanda
Published: March 2011

A Mobilidade populacional na Amazônia é motivada pela busca de novas oportunidades de trabalho, fato atrelado às mudanças estruturais, relacionadas à ação do Governo Federal por meio de políticas territoriais iniciadas ainda nos anos 60 e 70. A implantação de projetos de infra-estrutura estabelece diferentes funções e reestruturações espaciais, constituindo novos padrões de organização social, econômica e cultural. Atualmente, em Porto Velho-Rondônia, a construção das hidrelétricas de Jirau e Santo Antônio, no rio Madeira, iniciadas em 2008, tem sido questionada quanto ao novo fluxo populacional, o qual pode ser caracterizado por dois processos: o de territorialização e o de desterritorialização. O primeiro processo é marcado pela atração populacional, dado pela oferta de trabalho e, o segundo, pautado na desterritorialização devido ao deslocamento populacional na área do reservatório, apresentando como caso mais crítico o da comunidade de Mutum-Paraná, com o comprometimento total do seu núcleo urbano. O objetivo deste artigo é avaliar a mobilidade populacional e a relação entre a implantação de infra-estrutura e exploração dos recursos naturais na área de influência das hidrelétricas. A metodologia parte da análise temporo-espacial com revisão de literatura, trabalho de campo e coleta de dados geográficos da área. As variáveis utilizadas foram: população, principais atividades econômicas e normas de uso do território (legislações). Estas variáveis permitiram compreender as relações entre sociedade e espaço no seu processo de organização e transformação. As análises indicaram que nesta área, desde sua ocupação até os dias atuais, a mobilidade populacional tem sido motivada pela implantação de obras de infra-estrutura, apropriação e exploração intensiva dos recursos naturais sem estabilidade econômica, resultando em fluxos e refluxos migratórios.
Application of Genetic Algorithms on Parameter Estimation of HVDC Circuit Breaker
Authors: Jin Tao , Chen Wei , Ning Tao
Published: March 2011

In order to estimate the parameters of capacitance, inductance and resistance in oscillation circuit DC circuit breaker a method of parameter estimation of High-Voltage circuit break based on genetic algorithms is proposed and which can properly assess the performance of DC circuit breaker. In this paper A genetic algorithm is introduced and applied in parameter estimation of High-Voltage circuit breaker and then compare it with the traditional MATLAB curve fitting, the result clearly reveal the advantages of genetic algorithm.
A Gyrobondgraph Method of Dynamic and Static Force Analysis for Spacial Multibody Systems
Authors: Wang Zhong Shuang , Chen Ji , Xu Chang Shun
Published: March 2011

In order to increase the efficiency and reliability of dynamic and static force analysis for spatial multibody systems containing the coupling of multi-energy domains, a method based on gyrobondgraph is introduced. The procedure of modeling spacial multibody systems by bond graphs and its dynamic principle are described. The unified formulae of driving moment and constraint forces at joints are derived based on gyrobondgraph, they are easily generated on a computer in a complete form. As a result, the very difficult algebraic problem caused by differential causality and nonlinear junction structure can be overcome, and the automatic dynamic analysis of multibody systems on a computer is realized. By a practical example, the validity of this procedure is illustrated.
Inchworm-Type Wheeled Mobile Robot Modeling and Simulation
Authors: Zhang Lei , Cheng Xiao Min , Hu Hua , Chen Meng
Published: March 2011

Inchworm-type wheeled mobile robot is a non-comprehensive, all-driven system. This paper establishes a kinematical model for such system. Based on the kinematical model, the motion of the system is analytically studied, and the simulation of the motion for this system is conducted with the means of Pro/E. The system in the dynamic motion presented make the collision avoidance and path seeking easier. It also provides a motion mould for the simulation, and proves the theoretical analysis is right.
Effect of Turbulence Parameters on Numerical Simulation of Complex Automotive External Flow Field
Authors: Hu Xing Jun , Qin Peng , Guo Peng , An Yang
Published: March 2011

Numerical simulations for the Ahmed model with 25° slant angle are performed under three different turbulent parameters, intensity and length scale, intensity and viscosity ratio, k and epsilon. The external flow field of ahmed model with 25° slant angle is got, and all the velocity vectors, pressure distribution and the drag coefficient of the flow field are obtained as well. The comparison between the numerical simulations and the experimental statistics shows that intensity and viscosity and k and epsilon characterized by higher computation accuracy are more suitable for numerical simulation of automotive external flow field.
Rigid Body Modes on Non-Linear Resonant Decay Method
Authors: Sarmast Mehdi , Wright Jan R.
Published: March 2011

Non-Linear Resonant Decay Method (NL-RDM) addresses the identification of multi-degree of freedom non-linear systems. This method offers a practical approach to the identification of lumped parameters and continuous systems by producing a non-linear extension of the classical linear modal model. This paper is concerned with the inclusion of residual modes, below any region of interest. Any structure that is not supported to earth will have rigid body modes, being modes that have a natural frequency at zero Hertz; a good example is an aircraft. These modes are sometimes ignored but for a complete mathematical model obtained from NL-RDM the effects of rigid body modes must be analysed. NL-RDM relies on a method of curve fitting to generate modal characteristics, in terms of force, displacement, velocity and acceleration in modal space. The lower residual region was observed to contain rigid body modes. Monitoring this effect was shown to be too difficult currently for the NL-RDM, given technological restrictions. A Mass Substitution method was generated to model the system response more accurately. Its accuracy was demonstrated through case studies.
Research on the Bubble Motion near Free Surface in Underwater Explosion
Authors: Li Jian , Rong Ji Li , Xiang Da Lin
Published: March 2011

A model for a moderately deep underwater explosion bubble was developed in inviscid and irrotational fluid. Considering the effects of gravity, buoyancy, drag to the motion of bubble, the equations of motion (EOM) for bubble in inviscid and irrotational fluid near a free surface were established by introducing the potential-flow theory, energy equation and Hamilton principle. The displacement of the center of bubble, the radius-time histories and impulse periods of bubble were acquired by solving the EOM. The calculated results were compared with the experimental and numerical results. The compared results show that the former is consistent with the latter. The research has value to correlative theory research and engineering calculation.
Circuit Design for Alternating Current Field Measurement Make Use of Lock-in Amplifier
Authors: Ren Shang Kun , Yang Yao , Li Zhong Ji
Published: March 2011

In ACFM, the measured signal is very weak and always inevitably includes the noises and the unwanted signal. Make use of lock-in amplifier technology to have designed a disturbance magnetic field testing circuit which includes eliminating 2.5 volt DC circuit, amplifying and filtering circuit, phase-shifting circuit and switching voltage multiplier. This circuits designed can performe the measurement and do-nosing for weak magnetic signal of ACFM. The experiment indicated that make use of lock-in amplifier technology to design and optimize ACFM detection circuit is an effective method
The Finite-Element Analysis of Cylindrical Helical Tooth Milling Cutter Based on Marc
Authors: Zhang Guang Guo , Jiang Wei , Zhang Hong Hua , Wang Huan
Published: March 2011

In the traditional designs of milling cutter, we cannot get the required accuracy of machining as there may be local deformation on the edges, even more the cutter can break down. Aiming at this situation, a finite-element model of straight pin milling cutter with helical tooth are built using Marc, a nonlinear finite-element analysis software, the different cutting forces of the milling cutter during the cutting process are analyzed and the cutting forces of the milling cutter at different parameters are studied. We get the stress, the strain and the temperature distribution of the milling cutter in different situation. Our work offer a theoretical basis of improving stress of the cutter, designing the structure of cutters reasonably and analyzing the cutter failure as well as a new method of analysis and calculation of the cutter life and strength.
Fault Prediction of Induction Motor Based on Time-Frequency Analysis
Authors: Treetrong Juggrapong
Published: March 2011

Because the faults happening in the motor (such as the stator and the rotor faults) can distort the sinusoidal response of the motor RPM and the main frequency, hence the spectrum method has previously been introduced which it relates to both amplitudes and phases among harmonics in a signal. The method popularly applied for fault detection is based on frequency analysis by observing the side band, its harmonics around main frequencies or its other harmonics. Based on the present experiments, the spectrum method by FFT function has ability to distinguish the motor condition. But, the fault severity levels seem to not able to analyze. Hence the time-frequency Analysis (or spectrogram) of the stator phase currents is proposed here. The method is expected to show relation between the phase current signals and the fault levels which make it can detect the faults and also indicate the fault levels. The experiments show that the proposed method can provide good accuracy for fault prediction and fault level quantification. Hence it can conclude that the propose method can be an effective tool for motor fault prediction.
Operating Temperature Effects on Water Transport Behavior in a Single Cell PEMFC
Authors: Erni Misran , Nik Suhaimi Mat Hassan , Wan Daud Wan Ramli , Majlan Edy Herianto , Miftah Kurniawan
Published: March 2011

Flooding and membrane dehydration are phenomena that must be avoided in a proton exchange membrane fuel cell (PEMFC) operation. It needs a sufficient knowledge about water transport behaviors. Electro-osmotic drag and back diffusion are the dominant water transport mechanisms through the membrane in PEMFC. In this study, the relative humidity (RH) profile along the channel at both anode and cathode sides have been recorded. The experiment was conducted in a single cell PEMFC with single serpentine flow field design. The water content profile was strongly influenced by RH profile thus in turn influenced the electro-osmotic drag coefficient, water diffusion coefficient and back diffusion flux. The operating temperatures of cell also influence those water transport behavior. The temperature was varied at 25, 40, 50 and 60 oC, while the pressure at the anode and the cathode was fixed at 1 bar. The higher the temperature, the smaller the water contents but with higher electro-osmotic drag coefficient, water diffusion coefficient and back diffusion flux. After all, the strategy of using saturated hydrogen and dry air in this study successfully prevents flooding and membrane dehydrating in the system – that are the major problems in PEMFC operation.
Computational Intelligence Techniques to Fault Detection in the Semiconductor Manufacturing Process
Authors: Kerdprasop Kittisak , Kerdprasop Nittaya
Published: March 2011

The semiconductor industry deals with the production at a scale of nanometer, thus resulting in the process control with little margin of error. Timely detection of faults during the manufacturing process is critical to the improvement in product yields. Difficulty of detecting accurately faulty processes and products is due to the abundant of data obtained from hundreds of tool-state and process-state sensors. We thus analyze this problem through the computational intelligence techniques. The analysis results reveal the minimal set of features for fault detection as well as the high precision classification model of faults.
Preparation and Evaluation of BaxSr(x-1)CoyFe(y-1)O3−δ Nanomaterial for SOFC Cathode by Oxalate Co-Precipitation (x=0.2, y=0.8)
Authors: Ahmadrezaei Mojgan , Muchtar Andanastuti , Muhamad Norhamidi , Tan Chou Yong
Published: March 2011

A recently reported promising new perovskite oxide cathode material, Ba0.2Sr0.8Co0.8Fe0.2O3−δ, (BSCF) (with x = 0.2 and y = 0.8) of high purity for intermediate-temperature solid oxide fuel cells (IT-SOFCs) was synthesised in the current work by using the co-precipitation method. The result indicated a precursor with a well-deﬁned composition of ﬁne particle size, high homogeneity, and high reactivity. After calcining has been developed at 900°C, the individual oxides from ammonium oxalate were alloyed into nanostructured perovskite (with x = 0.2 and y = 0.8) Ba0.2Sr0.8Co0.8Fe0.2O3 of high purity. The thermal properties, phase constituents, surface area and microstructure of the samples were characterised by TGA, XRD, BET, SEM and EDX techniques respectively. The results show that the BSCF powders have cubic perovskite-type structure with fine particle size, high surface area and high homogeneity. The current method employed is found to be very reliable for the synthesis of BSCF.
The Key Technology Research of Knowledge Modeling Method for Complex Product Design
Authors: Wan Neng , Mo Rong , Chang Zhi Yong
Published: March 2011

The purpose of this paper is to build knowledge description model for complex product design. In order to uniform the semantic of glossary in design process, an extensive glossary semantic tree is built up and the corresponding semantic similarity calculation algorithm is proposed. The complex design knowledge can be divided into instance pattern, chart pattern, formula pattern and rule pattern. The knowledge models are proposed for these four pattern knowledge models. At last, a design knowledge modeling and reusing system for complex product is achieved, and the design knowledge can be inherited by it.
Experimental Study on Engine Control Strategy during Gear Shifting for Vehicles Equipped with Automated Mechanical Transmission
Authors: Wan Guo Qiang , Huang Ying , Zhang Fu Jun , Cui Tao
Published: March 2011

This paper presents an experimental study on engine control strategy during gear shifting for a Unimog U4000 equipped with an automated mechanical transmission (AMT) based on the controller area network (CAN) bus. First, an integrated powertrain control system based on the CAN bus is introduced. Second, the ideal AMT gear shifting process is described, and the engine control strategy during gear shifting is proposed. Then, the communication information for the engine control unit (ECU) and transmission control unit (TCU) during gear shifting is determined based on the SAE J1939 protocol. Finally, effectiveness is verified by the experimental results. The experimental results show that: engine control during gear shifting based on the CAN bus can meet the requirement for real-time operation; the engine control strategy presented in this paper during gear shifting can achieve good shift quality with shorter shifting time and less vehicle speed loss.
Some Random Fixed Point Theorems and Comparing Random Operator Equations
Authors: Chen Ning , Tian Bao Dan , Chen Ji Qian
Published: March 2011

In this paper, some new results are given for the common random solution for a class of random operator equations which generalize several results in [4], [5] and [6] in Banach space. On the other hand, Altman’s inequality is also extending into the type of the determinant form. And comparing some solution for several examples, main results are theorem 2.3, theorem 3.3-3.4, theorem 4.1 and theorem 4.3.
Computational Fluid Dynamics and its Application in Gas Control of Goaf
Authors: Kang Xue , Chen Chang Hua , Teng Ren Chong , Su Jian Ye
Published: March 2011

In recent years, study on the regularity of gas moving has been emphasized due to the more seriously problem of mine gas which caused by the ever increasing of mining depth and rate in the coal. As the important source for the workplace gas, the goaf gas always causes a exceeding of the safety limit at the upper corner, it not only influences the sustainability, stability and security of the mines, but also serves as the primary cause of the accidents. In order to discuss the migration and distributed rule of the goaf gas, this article based on computational fluid dynamics, in accordance with the seepage theory and on the premise of analysised the fluid state of goaf gas, the distribution rule of goaf gas moving has been studied by establishing a mathematical model of gas seepage and distribution in the goaf area with a given boundary condition. The research has provided theoretical basis for the analysis of gas density at the upper corner of the mines, demonstrating its theoretical and practical significance in preventing gas overrun and safeguarding safety in coal mining.
Free Vibration Analysis for Disconnected Thin Rectangular Plate with Four Free Edges on Nonlinear Elastic Foundation
Authors: Xiao Yong Gang , Yang Cui Ping
Published: March 2011

In this paper, the free vibration analysis of thin rectangular plate with dowels on nonlinear elastic foundation is investigated. The load transfer on dowels is modeled as vertical springs, whose stiffness depends on the dowel properties and the dowel-plate interaction. Based on Hamilton variation principle, the nonlinear governing equations of thin rectangular plate with discontinuities on nonlinear elastic foundation are established, and the suitable expressions of trial functions satisfying all boundary conditions are proposed. Then, the equations are solved by using Galerkin method and harmonic balance method. The numerical simulation reveals the effects of the dowel parameters and the other ones of the system on free vibration behaves of the disconnected thin rectangular plate.
Study on Shear Rheological Behavior of Konjac Glucomannan
Authors: Wang Chao , Xu Mei , Zhu Yu Peng , Qiao Yu , Liang Ting Ting
Published: March 2011

Konjac glucomannan (KGM) belongs to pseudoplastic fluid. Remarkable non-linear change tendencies of shear rheological behavior of KGM were detected through analysis of the correlation of viscosity (η)-shear rates and shear stress-shear rates respectively, and its shear rheological curves conformed to the Power Law (τ=ＫDn). The change tendencies of viscosity factor (K) and flow index (n) correlated with concentration and temperature were also obtained, the curves can be fitted by power and quadratic polynomial equation respectively. The acquired non-linear correlation curves of K and n can provide reliable foundation for rational applications of KGM in food industry and its grade estimation.
An Improvement of the Preparation Method of Carboxymethyl Konjac Glucomannan
Authors: Wang Chao , Zhu Yu Peng , Xu Mei , Qiao Yu , Zhang Wei Hua
Published: March 2011

The improvement of the preparation method for carboxy methylation of konjac glucomannan (KGM) was proposed in this paper according to molecular structural characteristics of KGM. Carboxymethyl konjac glucomannan (CMK) were yielded by first blending KGM with etherification agent and then basifying and catalyzing in ethanol. Through single factor and orthogonal experiments, the effects of reaction conditions on degree of substitution (DS) and apparent viscosity (η) were investigated, and the optimum reaction conditions were obtained as follow: 55°C, pH12 for 3 hours. The results indicate that the maximal value of DS and η were 0.5278 and 15.57Pa•s respectively. The reaction mechanism for carboxymethyl of KGM was proposed and checked by infrared spectra. Meanwhile, it is showed that the properties of CMK were rather good in terms of hydrated rate and hydrosol transmittance.
A CAE Approach for Pretest Analysis of Vehicle Body Frame Vibration Test
Authors: Lu Shou Wei , Feng Hui Hua , Zuo Zheng Xing , Yue Feng Lai
Published: March 2011

Pretest analysis is a crucial step of the process for experimental modal analysis, directly affect the test accuracy. A general procedure for pretest analysis of a vehicle body frame has been presented using CAE approach with software Virtual Lab. After the modal parameters are acquired from FEM analysis, the CAE based MAC method is used to optimize the measurement location and direction. The selection of an appropriate set of measurement locations and directions including initial accelerometers placement and test excitation point location are defined based on MAC method by Virtual Lab correlation part. Finally, for purpose of validation, the FEM modal analysis is compared with operational modal analysis. The results comparison showing that the present pretest analysis approach is more accuracy and efficiency.
Noise Prediction for Multi-Element Airfoil Based on FW-H Equation
Authors: Tao Jun , Sun Gang , Hu Ying , Zhang Miao
Published: March 2011

In this article, four observation points are selected in the flow field when predicting aerodynamic noise of a multi-element airfoil for both a coarser grid and a finer grid. Numerical simulation of N-S equations is employed to obtain near-field acoustic information, then far-field acoustic information is obtained through acoustic analogy theory combined with FW-H equation. Computation indicates: the codes calculate the flow field in good agreement with the experimental data; The finer the grid is, the more stable the calculated sound pressure level (SPL) is and the more regularly d(SPL)/d(St) varies.
Stress and Probabilistic Study of the Lumbar Vertebra under Compression Loading
Authors: Zulkifli A. , Ariffin Ahmad Kamal , Ismail A.E. , Daud Ruslizam , Akramin M.R.M.
Published: March 2011

The objectives of this study were to determine the stress concentration of the lumbar vertebra and the probability of failure associated with finite element method. The lumbar vertebra model was constructed in SolidWorks software and imported by ANSYS software for the analysis. In this work, all the model components were meshed using the tetrahedral solid element (SOLID186). In order to simplify the model, all the spinal components were modeled as an isotropic and elastic material. Monte Carlo Simulation (MCS) technique was performed to conduct the probabilistic analysis using a built-in probabilistic module in ANSYS with attempt for 100 trials. The results were observed that the highest stress concentrations were found in the adjacent posterior vertebral body with 1.2117 MPa and the corresponding probability of failure for the model is 3%. Sensitivity analysis had been revealed that the force applied to the facet (FORFCT) variable was sensitive to the stress and displacement output parameters and need to be emphasized. The current probabilistic study was very useful as a tool to understand the inherent uncertainties and variations in biological structures.
Thermal Design of a Satellite Borne FPGA
Authors: Chen Bo
Published: March 2011

Thermal design and analysis of a satellite borne FPGA is described in this paper. Thermal-conductive glue, vias and an aluminum bar were used to the FPGA and the PCB under the FPGA in order to help conduct the heat of the FPGA to heat sink. The results of finite element analysis showed that the case temperature of the FPGA decreased from 132.5°C to 55.4°C and the junction temperature decreased from 136.1°C to59.0 °C after the thermal design, which matches the requirements of thermal design.
Numerical Method for Pressure Distribution Calculation on Spherical Distribution Pair of IHT
Authors: Yuan Shi Hua , Liu Ding Hua , Wei Chao
Published: March 2011

To calculate the pressure distribution of oil film on spherical port plate of Innas hydraulic transformer (IHT), finite difference method (FDM) based on boundary fitted coordinate (BFC) technique is presented. Spherical curvilinear grid system was obtained with a coincident boundary of irregular physical area. The flux conservation form of Reynolds’ equation was applied as control equation. By FDM, the thickness distribution and pressure distribution of distribution pair were calculated. It shows that BFC transformation method is advantaged to closely simulate the physical domain with complex geometrical boundaries.
Application of Clustering Analysis Algorithm in Sorting Stochastic Vibration Environment Measured Data
Authors: Chang Hai Juan , Zhang Jian Jun , Zhu Shu
Published: March 2011

Environment measurement technology of aircraft platform is the foundation of environment prediction, while inductive technology of environment measurement data is the support of environment prediction. To analysis how the vibration of different channel and in different position affect the equipment on board, it’s awfully needed to classify the vibration data of aircraft platform according to how was the aircraft flying and where was the sensor placed. However, the traditional method for categorizing gives the sort first, and then make certain if one sample belongs to this category, which is easy to withstand the influence of man-made factors. As it hard to fix the categories first for the vibration on aircraft platform, we put forward using clustering analysis into the categorizing of vibration measured data to eliminate the influence of man-made factors. This method is the improvement of the current inductive method for vibration environment measured data.
Research on the Semantics Encoding of Interior System of Railway Passenger Car
Authors: Zhang Bing Chen , Guo Wei Min , Wang Yan Qun
Published: March 2011

The development of interior design is an important aspect of improving the quality of railway transportation services. Product semantics not only pay attention to the physiology function, but also go deep into psychology function. The core of semantics communication is encoding rule. It would ensure the two basic processes that encoding and decoding go smoothly in semantics communication. Thus it would improve the interior system design of the railway passenger cars effectively that paying attention to the characteristics of encoding rules.
A Statistical Based Analysis Approach on Fatigue Failure Assessment of Carbon Steel
Authors: Padzi Mahfodzah M. , Abdullah Shahrum , Nuawi Mohd Zaki
Published: March 2011

This paper discussed on an application of the statistical based analysis approach on fatigue failure of carbon steel. A new statistical based method known as Integrated Kurtosis-based Algorithm for Z-filter (I-kaz) and the quadratic mean were used in this fatigue failure assessment. Fatigue tests were performed according to the ASTM E466-96 standard with the attachment of a strain gauge to the tested specimen. Test was performed at a constant loading leading to the collection of strain data throughout the test. A fatigue based data acquisition system was used in this work. All obtained data were analysed using specific software. Fatigue failure behaviour was observed through the strain signal analysis to investigate significant correlation between I-kaz coefficient, root mean square value and the fatigue failure behaviour. It was found that I-kaz coefficient and root mean square value are proportional to life cycle.
Bank Lending and Trade Credit: Evidence from Chinese Firms
Authors: Ma Zhong Hua
Published: March 2011

The determinants and roles of bank lending, which is formal financing channel and outsides the supply chain, and trade credit, which is informal financing channel and insides the supply chain, are analyzed here through listed firms in China over 2006-2009. In our model we consider the trade credit as a complementary role and more important for small firms. Also with the firms different industry classified, we give the performance of bank lending and trade credit respectively. The estimation results and analysis are given detailed in our paper.
Component Analysis of Adiabatic Shear Band Formed in High Speed Cutting of High Strength Alloy Steel
Authors: Duan Chun Zheng , Wang Zhao Xi , Wang Min Jie , Kong Wei Sen
Published: March 2011

The component distribution of adiabatic shear banding during high speed cutting(HSC) is important to understand the phase transformation during formation of adiabatic shear band and mechanism of serrated chip formation. This paper analyzed element distribution inside and near the adiabatic shear bands formed during HSC of 30CrNi3MoV high strength steel using electronic probe. It was found that there is no obvious element segregation, but carbon element tends to gather towards adiabatic shear band’s boundaries. The density of carbon inside the shear bands tends to increase with the increase of cutting speed. The results indicated that the diffusion and gather of carbon may occur during formation of adiabatic shear band. The diffusion mechanism may be short-range diffusion driven by high-speed deformation and high temperature rise.
Dynamic Analysis of Lunar Rover Elevator Road-Set Deploying and Locking
Authors: Li Kui , Liu Rong Qiang , Deng Zong Quan , Jiang Sheng Yuan
Published: March 2011

The first task of a lunar rover elevator after landing is to deploy road-set. Vibration amplitude is large and attenuation time is very long because of low material modal damping and litter outer damping on lunar, which can be a disaster for a space mission. The paper built the road-set deploying rigid-flexible coupling simulation model by ADAMS and Nastran software and measured the acceleration of the inner and outer road-set end by experiment. Simulation and experiment results show that gravity, material damping coefficient and torsion spring parameters influence to road-set vibration greatly and the methods to restrain road-set vibration are to optimize joint torsion spring parameters by kinetic energy least restrict and to enhance attenuation speed by optimizing the road-set appearance and increase its damping coefficient.
Road Adhesion Coefficient Estimation
Authors: Sun Yan An , Xiong Lu , Yu Zhuo Ping , Feng Yuan , Ren Long Jie
Published: March 2011

Taking four in-wheel-motor electric vehicle as research subject, the paper focuses on the estimation of road adhesion coefficient based on curve. Through adding a forget factor, an improved algorithm on the basis of Forget Kalman Filter is proposed to estimate the slope of the curve at low slip rate. This new algorithm is proved effective through the real car test.
Numerical Simulation of Ventilation Air Methane Counter-Current Oxidation Reaction
Authors: Wang Ying Hua , Jia Bao Shan , Shi Jun Rui , Deng Yang Bo , Tian Yu
Published: March 2011

In this paper, based on the theoretical analysis and reasonable simplification, one-dimensional mathematical model is presented for the counter-current oxidation of ventilation air methane. The process of counter-current oxidation reaction is simulated by applying the computational fluid dynamics (CFD) software (Fluent), and the effect of the dominating working parameters (such as flow velocity and equivalence ratio and half cycle) are discussed on the temperature and rate of reaction within the counter-current oxidation reaction. The distribution of the temperature field and the reaction rate are simulated when half cycle is 30s, the equivalence ratio is 0.2 and the velocity 0.06 m/s, 0.1m/s and 0.2 m/s. The combustion characteristics are summarized for the device of counter-current oxidation reaction, and the effects of working parameters are analyzed on the burning characteristics. It is so important to increase the combustion efficiency and energy utilization.
Numerical Simulation of 6061 Aluminum Alloys during the Semi-Solid Backward Extrusion
Authors: Shang Shu Zhen , Lu Gui Min , Tang Xiao Ling , Zhao Zu Xin , Cao Wei
Published: March 2011

Effects of deformation temperature and strain rate on deformation behavior of semi-solid 6061 alloy were investigated on Gleeble3800 thermal-mechanical simulator. On basis of the experimental data of semi-solid 6061, a model was established to describe the relationship between the processing parameters and flow stress, which showed that the experimental results and calculation ones fitted well. It would be beneficial to realize the distribution of stress and strain during the semi-solid forming on the basis of numerical simulation technology. This research paper presented the numerical simulation results of the 6061 alloy during the backward extrusion thixoforming process.
Post-Earthquake Experimental Research and Microscopic Analysis on Fatigue Behavior of Recycled Aggregate Reinforcement Concrete
Authors: Yan H.Q. , Wang Qing Yuan
Published: March 2011

In consistent with sustaining development, recycled aggregate concrete (RAC)that is made from recycled concrete aggregates could be a perfect solution to resource and environment preservation. It is a kind of practical and economic material to reuse the great amount of construction and demolition wastes, which has received many discussions nowadays. But, its fatigue behavior is different from other concretes as a result of different property of the aggregate of recycled concrete and other concrete. In order to apply RAC more effectively, it is necessary to study its properties especially for those aggregates from earthquake-stricken area for post-earthquake reconstruction. Therefore, on the basis of experimental research, the fatigue behaviors and microstructure of recycled concrete are studied in this paper. The present paper deals with investigations on fatigue behavior of the axial and eccentric compression performance of recycled aggregate reinforcement concrete specimens with contain recycled aggregate proportion of 0%、50%、100%. Then micro-structural observations of the specimens by means of scanning electron microscopy (SEM) were obtained. Based on the analysis of experiment results, it can be proved that it is feasible to apply recycled concrete to practical engineering.
Numerical Simulations of Aerodynamic Feature for Variable Speed Offshore Wind Turbine
Authors: He Ping , Chen Nai Chao , Hu Dan Mei
Published: March 2011

The liquid-gas flow is proposed to accurately simulate the offshore environmental state. The aerodynamic feature is estimated using the three-dimensional model of horizontal-axis wind turbine with NRELS809 series aerofoil by means of the simulating software tool of FLUENT. The variable speed is implemented via the six different wind speeds. The calculated results show that the similarly evolutional tendency of velocity occurs in the wake region when operating at the six variable speeds. The stall speed is related to blade height and wind speed. The small blade height or large wind speed also leads to the serious stall phenomenon. The total force is conducted to estimate the potential capability for leeward and windward surface to capture wind power. The calculated results reveal that the larger wind speed facilitates generating the more magnitude of total force. However, the velocity and force feature for the wind turbine has the especially rapid change at the wind speed of 6 m/s, which perhaps results from the intrinsic geometry and configuration.
Expert System of Full-Mechanized Face Equipment Fitting Based on Artificial Neural Network
Authors: Gao Feng , Xiao Lin Jing , Zhong Wei Yan , Liu Wei
Published: March 2011

Expert system of full-mechanized face equipment fitting based on artificial neural network is researched and processing method is presented in this paper. On the basis of this, BP neural network models for the forecast of production capability of mining face and the parameters of equipment fitting of full-mechanized mining face are built up. Employing these models forecasts the output, work efficiency and main technical parameters of full-mechanized equipment of the test mining face in Ji'er Colliery.
The Study of Active Noise Control Method for Moving Target in Noisy Space
Authors: Liao Yan Jian , Slade Alan , Luo Hong Yan , Chen Li
Published: March 2011

For the noise problem of moving target in noisy space, This work is dedicated to developing a novel and promising solution based on the moving target tracking technology and the active noise control (ANC) technology. The development process began with the simplified sound field interaction model, the “auto position tracking near head space ANC” strategy has been proposed from the modelling study. Furthermore, the primary experimental system that consists of the acoustic positioning and tracking subsystem for tracking the control point and the ANC subsystem for generating the anti-noise signal is presented, with the emphasis on the development of the improved TDC-FXLMS ANC algorithm. Finally, the performance of the auto-position tracking near head space ANC device is evaluated by carrying out the primary experiments on an experimental evaluation system.
Research about Detection System of Hydrogen Engine
Authors: Wang Li Jun , Wang Xu Hu , Guo Hui Juan
Published: March 2011

This paper describes a detection system design method of hydrogen engine based on LabVIEW. In order to understand the characteristics and working status of hydrogen fuel engine, we have developed a set of hydrogen fuel engine test system. In the system, LabVIEW is used as the software and DAQ PCI-1802H is the hardware, which mainly realizes the collection, testing, comparison analysis of engine signals and its feature parameters. It has strong functions of signal analysis and processing as well as nice user interface.
Effects of Mesh Size and Target Dimension on Numerical Simulation of Shaped Charge Liner Penetration into Target
Authors: Miao Qin Shu , Wang Xiao Ming , Zheng Yu
Published: March 2011

In order to solve two problems when simulating the phenomenon of Shaped Charge Liner penetrating into target, an example was simulated to study the influence of mesh size and target dimension on the penetration results using AUTODYN-2D. The relationship between the Shaped Charge Liner parameters and the critical dimension of the target was gained．The effects of mesh sizes on the penetration depth, aperture，and calculation time were studied. After analyzing the simulation results，a proper range of mesh size was obtained. The simulation results agree well with the test results. The research could provide reference on the simulation of Shaped Charge Liner.
Research on Mining Classification Rules of Spare Parts Based on Grey Rough Set Theory
Authors: Li Bo , Zhang Rui Fang
Published: March 2011

Mining classification rule of spare parts is very important for inventory management. In traditional classification work of spare parts, the attributes of spare parts were used as a standard to extract classification rules, but it was hard to know the influence of every attribute of spare parts, and which one should be considered, because the attributes of spare parts had many species. So it was necessary for inventory management to mine classification rules of spare parts. Because the values of many attributes of the spare parts are in form of the range of data, the grey rough set theory was borrowed to mine the classification rules in this paper. Firstly, the mining classification rules model of spare parts was built by the grey rough set theory. Then the attributes of spare parts were summarized, and the steps of mining data samples and the mining classification rules of spare parts were introduced respectively. Finally, case study from the classification management of the spare parts of a maintenance factory shows that the proposed mining classification rules model of spare parts based on grey rough set theory can reduce the unnecessary attributes of spare parts without affecting the results of classification.
Simulation of Fuzzy Self-Turning PID Control Based on Simulink
Authors: Chen Jian Wen , He Zhan Jun , Song Jin Chun , Pang Chang Jian
Published: March 2011

In CNC lathe servo feed system, many parameters are uncertain, so it is difficult to establish accurate mathematical model of the feed system, and parameters of conventional PID controller can not change the parameters to adjust with the controlled object. Fuzzy PID controller, which has the advantages of conventional PID control and fuzzy control, can solve these problems very well. So we can make it applied in CNC lathe servo feed system. This paper has made a simulation of fuzzy self-turning PID controller in the MATLAB environment. The simulation shows that the fuzzy self-turning PID controller has a better control capability and a higher stability, and it improved the servo feed system dynamic performance.
Study of Applied Properties of Aminosulphonic Acid Based Superplasticizer
Authors: Cui Shao Bo , He Feng Wei
Published: March 2011

The adaptability to cement pastes and fresh concretes of aminosulphonic acid-based superplasticizer (ASP) and its water reducing ratio and compatibility with Naphthalene based superplasticize (FDN) have been investigated at a given content of ASP. The adaptability to cement pastes was determined by measuring the fluiditiy with time of superplasticized cement pastes, and the adaptability to fresh concretes and compatibility with FDN was evaluated by measuring the fluidity, bleeding, and hardening and mechanical property et.al. of fresh concretes with ASP. The results show that the fluidities at 120 min of cement pastes, with 1.6% of ASP, are over 140 mm, and it increases with the increase of ASP. There is a positive relationship between the water reducing ratios of ASP and its content, and the highest of the water reducing ratio(the highest value is 28%). Moreover, the simultaneous addition of ASP and FDN can effectively decrease the bleeding of concrete.
A Multiattribute Measurement Algorithm for Packet Classification
Authors: Pen Mao Ling , Huang Ai Ming
Published: March 2011

Many network application technology need the algorithm for multi-dimensional packet classification, for example ,network security ,load balancing ,router policy, QoS etc. Considering the levels of multiattribute packet classified are excessive and traverse rule table times without number for matching classification rule, so efficiency is lower. A packet classification algorithm based on decision tree is put forward in the paper. As compared with some traditional packet classification matching algorithms, because three data are adopted including information gain, information gain ratio and Gini to solve attribute selection measurement, accuracy and matching efficiency are both advanced obviously.
Manufacturing High Nitrogen Austenitic Stainless Steels by Pressurized Induction Furnace
Authors: Li Hua Bing , Jiang Zhou Hua , Ma Qi Feng , Li Wan Ming
Published: March 2011

A 25kg pressurized induction furnace with maximum nitrogen pressure 6MPa was invented to manufacture high nitrogen stainless steels. The suitable process was explored, and the analysis of radiography and macrosegregation of nitrogen of high nitrogen steel ingot was performed. The mechanical properties and inclusions of the forging ingot were also investigated. The suitable solidification nitrogen pressure can effectively prevent the formation of nitrogen porosity and macrosegregation of nitrogen. It is very important to control the purity of the nitrogen gas to a higher level for avoiding the manganese loss and decreasing oxygen content in the steel during the nitrogen gas pressurized melting process. The sound and compact macrostructure high nitrogen austenitic stainless steel with nitrogen content above 1.0 wt % has been manufactured by the pressurized induction melting method. There are mainly nonmetallic inclusions with the size less than 5μm in the HNS-A ingot. The HNS-A exhibits excellent mechanical properties.
Heat Conduction Structural Topology Optimization Based on RAMP
Authors: Li Jia Chun , Tu Wen Te , Yang Xu Dong , Fu Jian , Wang Yong Tao
Published: March 2011

Based on topology optimization techniques of structural mechanics, an effective method for solving the structural design problems of heat transfer is presented in this paper. The topology optimization model of heat conduction is then constructed and the corresponding Optimization Criteria based on density approach is inferred to solve the optimal heat conduction equation of temperature field. A Filtering technique is employed in density field to eliminate numerical instabilities in the process of topology optimization. Some numerical examples are presented to demonstrate the accuracy and the applicability of the present method, theory and algorithm. This research provides a new idea and an access to the structural topology optimization design of temperature field, and is of good engineering application value.
Microstructure and Wear Resistance of Laser Cladded Coatings on Copper Substrate
Authors: Wang Wen Yan , Lu Gao , Dong Xiao Ming , Xu Jing , Xie Jing Pei
Published: March 2011

In order to improve the wear resistance of continuous casting crystallizer, Co-based alloy coatings were prepared on copper substrate by a pulsed Nd:YAG laser. Scanning electron microscopy, X-ray diffraction, microhardness and wear resistance testing were employed to study the microstructure and properties of the cladding coatings. The results show that the friction coefficient and wear mass loss of the cladded coating with the volumn ratio of Stellite X-40：TiC：CaF2=60：10：30 are both the smallest; the average microhardness of the cladded coating is 496.2HV0.2 which is about five times higher than that of the substrate.
Strength Analysis of Damaged and Local Reinforced Cylinder Ocean Structure
Authors: Zhao Cun Sheng , Zhu Shi Jian , Wang Lu
Published: March 2011

Three models were established in this paper to analyses the strength of intact, damaged and reinforced pressure hull of ocean structure. Linear elasticity and elastoplasticity FEA method were adopted. The results showed that replacing rib and local reinforcing damaged pressure hull could not restore the performance of pressure structure. Other methods must be considered.