bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic Analysis of Support System of Permanent Magnet Traction Motors for High-Speed Trains
Authors: Li Ting , Zhang Jian Cheng , Fang You Tong
Published: September 2013

During the operation, the high speed train will be subject to random vibration load induced by the roughness of the rail and will cause the vibration. Traction motor is critical component of traction system for high-speed train. It is subject to not only static loads, but also random vibration load. This kind of random vibration load may easily lead to fatigue damage of the structure, which will finally cause adversely effect to the motor. Thus, in this paper, a 3-dimension model of the support system of traction motors in high-speed train applications is built, and the static and modal analyses are undertaken using finite element calculation software. The simulation results confirm that the support system is robust enough to meet the design requirements of strength and stiffness. Furthermore, it has a larger margin of safety in a typical case which meets the technical requirements for safe operation of the high-speed train.
Study on Comprehensive Measures of Long-Term Stable Dense Oil Reservoir
Authors: Wang Yong , Shao Dong Bo , Lu Hong Jun , Lu Xiao Bin
Published: September 2013

water injection development is an effective means of tight reservoir to maintain formation energy, and high formation pressure is the basis of reservoir maintain a long-term and stable, therefore, give enough water injection, so as to maintain high pressure is the key to maintain the long-term stability of the reservoir. Liu Maoyuan block Changqing Oilfield is a typical part of tight sandstone reservoir, water injection wells long is not up to the demand of injection, after fracturing, acidizing by invalid injection measures, is not conducive to long-term and stable block. Therefore, research on comprehensive countermeasures of long-term stability of dense oil reservoir. Through the research and development of new antihypertensive drag reduction agent for the overall pressure on block; select suitable for dense reservoir single well stimulation measures and local boosting measures, measures ineffective wells and local abnormal pressure injection is difficult to solve the problem of the cause, to maintain formation pressure. A good result has been obtained by field test, effectively solve the tight reservoir by high-pressure injection resulted in not long-term stability problems, and provides a new idea and reference for solving dense reservoir long-term stability problem.
Prediction Scheme of Railway Passenger Flow Based on Multiplicative Holt-Winters Model
Authors: Wei Zhuo Min , Song Hong Chao
Published: September 2013

The railway passenger volume has an obvious seasonal behavior, and has volatility and instability. The features of it brings a lot of difficulties to forecast the volume in short-term. To investigate the trends and seasonal variations of railway passenger flow, we discuss multiplicative Holt-Winters model as a method. This paper states the basic theory and algorithm of the model, and provides the experimental results by using the data of China railway passenger volume in 2006 to 2010. The result shows the feasibility and effectiveness of the proposed approaches
Earthwork Calculation Based on GPS Discrete Elevation Points
Authors: Qiao Rui Bo
Published: September 2013

In the terrain smaller land formation zone, GPS discrete elevation points can quickly calculate the digging and filling side volume. Use the commonly used geographic information system software, and then select the auxiliary calculation the earthwork volume method based on the use of scattered elevation data, after the trial of the final design to meet the requirements of the plots elevation, you can improve the accuracy of calculation of the amount of earth in the land formation, so as to provide accurate data for the project planning, design and project budget.
Study on Allocation for Transportation Mode of Urban Agglomeration Transportation Channel
Authors: Li Lian Lian
Published: September 2013

Urban agglomeration transportation Passage is the foundation to develop the assembling and expanding effect of urban agglomeration, while allocation for transportation approach plays an essential part. According to the characteristics of the urban agglomeration channel, based on the objectives and principles of configuration mode of transport channel, through technical and economic analysis of the various modes of transport, the transport configuration model.
Research on an Economic Monitor and Decision Support System Based on Data Warehouse Technology
Authors: Kuang Ye , Xie Chao
Published: September 2013

Data warehouse technology is a new international pioneering research method which is developed by the urgent demands to adequately apply IT resources including Data Warehouse (DW), Data Mining (DM) and OLAP. The architecture and realization methods of an economic monitor and decision support system (DSS) based on DW are presented in this article.
The Application of the Analytic Hierarchy Process (AHP) in Mine Geological Environment Evaluation
Authors: Shi Shao Jian , Shuo Liang Xun , Cui Xing Tao
Published: September 2013

Mine environmental geological assessment usually uses the expert subjective assignment to determine the weights of affecting factors, but the mine environmental geological problems are the result of many factors. Each factor is complex on the suitability of the influence factors, and the factors interrelate and restrict each other, so the human factor is of great impact. Take the geological quality evaluation of the mine environment of Shanxi, Shaanxi and Inner Mongolia mining area as an example, this article discusses in detail the process of determining the weights of evaluation factors by using the analytic hierarchy process (AHP), which increases the scientific nature of the assignment and reduces the subjectivity, which achieves satisfactory results.
Study on the Maintenance Decision Making of Engineering Equipments Based on Fuzzy Reasoning
Authors: Ni Jian Guo , He Xiao Hui , Sun Jia Gen
Published: September 2013

In this paper, a decision ma;king model for faulted equipment maintenance ordering is established using the theory of fuzzy mathematics, and also a new method of maintenance ordering is proposed. Example analysis proves that a good effect is achieved by this method.
Application of Jacobi - Conjugate Gradient Method in the Two-Dimensional Magnetotelluric Forward
Authors: Zhu Chong Li
Published: September 2013

Using the finite element method and all kinds of numerical simulation method, A large-scale system of linear equations is solved eventually,the solution method of the system of equations largely determines the solution efficiency and precision of numerical calculation. The Jacobi iteration preconditioning conjugate gradient method is adopted, Both overcome the coefficient matrix pathological characteristics and the characteristics of slow convergence speed ,and avoid the disadvantages such as Newton's method to store and Hessian matrix is calculated and inversed,improve forward modeling calculation speed and accuracy. Guarantee for solving numerical stability and efficiency ,of the thick grid combined with verification, the algorithm is feasible and it is verified by coarse grid combine with fine grid.
Social Work Research under Automation Control
Authors: Wang Dan Dan , Zhou Shao Bin
Published: September 2013

On the basis of this article in the use of automation and control theory of factor analysis and cluster analysis to analyze the problems of university graduates reflected, to resolve these problems, focus on one of the root causes of these problems is not college students on the course of self-management science, the author use the greedy algorithm dialysis college students how scientific management of social work, and the corresponding countermeasures.
Linear Vernier Machine with Permanent Magnets only on Armature Side
Authors: Shimomura Shoji , Takano Masahiro
Published: September 2013

The conventional linear PM machines can be classified into the type which has armature on mover or the type which has it on stator. In either type it requires to lay the armature windings or the permanent magnets over a long distance in the application for long distance movement. It leads to high cost. Therefore, we proposed a linear vernier machine with the magnets only on armature side. This paper describes the theoretical proof and introduces comparisons of computed and experimental results. The comparisons agreed well. The prototype machine for the experiment had a problem due to less accuracy in assembly but we think it is not difficult to solve the problem.
Thrust Optimization and Thermal Analysis of a Water-Cooled Double-Sided Permanent Magnet Linear Synchronous Motor
Authors: Zhang Xin Min , Lu Qin Fen , Cheng Chuan Ying , Shi Jia Meng , Ye Yun Yue , Huang Xiao Yan
Published: September 2013

A water-cooled, double-sided permanent magnet linear synchronous motor (PMLSM) is studied by electromagnetic and thermal finite-element (FE) analysis method. Based on electromagnetic analysis, the better structure of this double-sided PMLSM can be obtained after thrust optimization by adjusting motor structure parameters. In order to minimize the thrust ripple, it is further optimized by shifting permanent magnets or armature iron cores of two sides for a small distance. With thermal analysis, the temperature distribution and transient temperature variation of this optimal PMLSM are investigated under the continuous operation and the short-time operation.
Analysis and Comparison Study on the Characteristic of High Power LIM and RIM for Traction Applications
Authors: Wang Ke , Shi Li Ming , Li Yao Hua
Published: September 2013

The characteristic of linear induction motor (LIM) is rather different to that of rotary induction motor (RIM). In this paper, the mathematic model of LIM is firstly developed based on the analysis of parameter variations. Then the mechanical and traction characteristic of the LIM and RIM are calculated and compared from different perspectives. Finally, the control law of LIM is deduced for the high performance traction control of linear motor metro vehicles.
Design and Electromagnetic Analysis of a Double-Sided Permanent Magnet Linear Synchronous Motor
Authors: Zhang Xin Min , Cheng Chuan Ying , Lu Qin Fen , Ye Yun Yue , Tao Xiao Sheng
Published: September 2013

The permanent magnet linear synchronous motor (PMLSM) has a good application prospect due to many significant advantages such as high speed, high precision, high thrust force density, simple structure, energy saving and reliable operation etc., so the research and development are of great importance. This paper mainly focuses on the key design points of a double-sided water-cooled PMLSM. According to the required thrust force, the design is given out including the basic structure parameters, winding connection methods and water cooling system. Based on the erected finite-element model, the performances such as back-EMF, thrust force, normal force, power factor and efficiency are predicted. By comparing with a single-sided PMLSM with the same specifications, it is proved that this double-sided PMLSM has lower thrust force ripple and higher thrust force density. Moreover, the net normal force of its mover is almost zero. Finally, the predicted back-EMF is verified by measurement.
Cogging Torque Analysis of Novel Dual-Rotor Axial Field Flux-Switching Permanent Magnet Machine
Authors: Hao Li , Lin Ming Yao , Xu Da , Fu Xing He , Zhang Wei
Published: September 2013

The cogging torque of a novel dual-rotor axial field flux-switching permanent magnet (DRAFFSPM) machine is investigated in this paper. The analytical equation of the DRAFFSPM machine is deduced. Based on 3D finite element method, the influences of the design parameters on the cogging torque are analyzed. The H-shaped stator tooth with slot chamfer is proposed and the slot opening width and chamfer thickness are optimized to reduce the cogging torque. It shows that the cogging torque is the minimum when the stator tooth width and stator magnet width equal to 8o and 7.5o mech., respectively. The cogging torque can be reduced by ~64% when the rotor pole width is 1.6 times that of the original design. The cogging torque can be reduced by ~80% when the chamfer is added in the stator slot.
A Linear Stator Permanent Magnet Vernier Machine Using Variable Halbach Arrays
Authors: Du Yi , Chau K.T. , Cheng Ming
Published: September 2013

This paper proposes a linear stator perment magnet (PM) vernier machine using variable Halbach Arrays (LSPMV-VHA machine) which offers a number of outstanding merits, such as the high thrust force and low cogging force. The key is to newly employ variable Halbach PM array to substitute the parallel PMs in the linear stator PM vernier (LSPMV) machine. By using the finite element method, the dimensions and the magnetization directions of the PM segments are optimized for the aim of the highest power density. In order to confirm the advantages, a quantitative comparison between the proposed machine and the LSPMV machine is performed in the conditions of the same PM volume, electric loading and rated speed. The results show that the proposed machine has higher power density and lower cogging force than its counterparts.
Performance Analysis of a Linear Motor with HTS Bulk Magnets for Driving a Prototype HTS Maglev Vehicle
Authors: Guo You Guang , Jin Jian Xun , Zhu Jian Guo , Lu Hai Yan
Published: September 2013

This paper presents the performance analysis of a linear synchronous motor which employs high-temperature superconducting (HTS) bulk magnets on the mover and normal copper windings on the stator. The linear motor is designed to drive a prototype HTS maglev vehicle in which the mover is suspended by the levitation force between HTS bulks on the mover and permanent magnets on the ground. Finite element magnetic field analysis is conducted to calculate the major parameters of the linear motor and an equation is derived to calculate the electromagnetic thrust force. Theoretical calculations are verified by the measured results on the prototype.
Comparison of a High Thrust Force Density Segmental Stator Linear Switch Reluctance Machine for with Different Topologies
Authors: Wang Dao Han , Wang Xiu He
Published: September 2013

Linear switch reluctance machine (LSRM) has been an alternative to linear permanent magnet synchronous machine and linear induction machine. However, the nature of reluctance force production, together with the air gap which is always much larger than rotary SRM, result in low propulsion force density in LSRM. This is an inherent demerit of LSRM, limiting its applications where the machine size is strictly set. This paper presents a novel linear switch reluctance machine with segmental stator, which consists of series of ferrite-magnetic segments. The principle of the proposed LSRM featuring high force density has been introduced. A variety of topologies of the proposed machine have been presented including single stator, dual stator and non-stator yoke structure. This paper deals with the comparison of the proposed segmental stator linear switch reluctance machine and traditional teeth type linear reluctance machine in terms of the propulsion force, normal force and force ripple as well as the force density and active pay load ratio. Finite Element Method is implemented to obtain the correlated results. Some conclusions are drawn to verify the analysis above.
Modeling the Effects of Magnetization Variations on a Permanent Magnet Based Levitation or Vibration Isolation System
Authors: van Casteren D.T.E.H. , Pluk K.J.W. , Paulides J.J.H. , Lomonova E.A.
Published: September 2013

When designing a magnetic levitation system it is assumed that the magnets are ideally magnetized. In practice, however, this is not the case and deviations occur in the magnetization. In this paper two types of deviations are considered, namely a constant angular deviation and the magnetization error. Calculations show that a constant error has larger impact on the performance of a gravity compensator than the magnetization error.
Analysis of Vibration Caused by Electromagnetic Force on Stator End-Winding of Large Dry Submersible Motor
Authors: Shan Li , Cheng Xiao Wei , Fang Yong , Bao Xiao Hua
Published: September 2013

This paper investigates the vibration which caused by electromagnetic on the stator end-winding of the large dry submersible motor. Firstly, the electromagnetic field which included transition state and steady state is researched by 3-D FEM. Secondly, the electromagnetic force which lead to vibrations of end-winding is calculated by numerical method, it can be obtained that where endured the largest force density along the slant part of end-winding. Finally, the radial displacement and the axial displacement of the slant part which caused by vibrations is studied, the analysis results show that the axial displacement is larger than the amplitude of radial displacement. It indicates that the slant part of end-winding will be more easily damaged at axial direction than radial direction.
Analysis on Single Photovoltaic Grid-Connected Inverter Control System
Authors: Liao Hong Fei , Liang Qi Feng
Published: September 2013

nverter can operate with power grid in parallel and can return the electricity generated by photovoltaic array with high power factor to power grid. The paper analyzes and compares several grid-connected current control methods, determines that the current control mode used in the design is improved SPWM current virtual value tracking control technology. And the paper analyzes and studies the transfer functions of key links of the inverter, and gives the derivation process of transfer functions. The control system uses dual-loop structure of inner current loop and outer voltage loop, and proposes the design methods of voltage loop and current loop PI regulator.
Study on SVM-DTC and Sensorless Technique in Long Primary Segmented Permanent Magnet Linear Synchronous Motor
Authors: Li Li Yi , Zhu He , Ma Ming Na , Chan C.C.
Published: September 2013

The thesis systematically researches electromagnetism and mechanical characteristic of primary segmented permanent magnet linear synchronous motor (PS-PMLSM), and discusses the varying rules of coupling flux linkage and inductance of each stator segment. The paper propose the space vector modulation direct thrust control (SVM-DTC) algorithm that based on thrust and flux observer, but also analyzes and builds adaptive slide mode observer (SMO), which adopts multi-segment estimate back-EMF combined method and phase locked loops (PLL) to estimate the position and speed of mover. Owing to the methods above, they are able to efficiently solve application problems in PS-PMLSM, which can't be settled through the conventional SVM-DTC and sensorless controlling method. Finally, the effectiveness of the algorithms is verified by simulation test.
Iron Core Hysteresis-Based Position Sensorless Control of PM Brushless DC Motors
Authors: Sun Wei , Shen Jian Xin , Li Peng , Wang Kang
Published: September 2013

A sensorless position detection technique based on iron core B-H hysteresis for PM brushless DC motors at standstill and low-speed is presented. A signal acquisition setup and a control method are provided. Experiments show that this technique has a good starting and low-speed control performance for both non-salient and salient motors. With this technique, a closed-loop starting can be achieved and the start-up time can be shortened. This technique has a wide adaptability and has good application prospects.
Research of Sliding Mode Control with Integral Compensator for Permanent Magnet Linear Synchronous Machine
Authors: Liu Ying Quan , Sun Dong Ru , Ye Yun Yue
Published: September 2013

In order to solve the high-frequency chattering and low anti-disturbance in conventional variable structure control (VSC) method with sliding mode, a compensator scheme of introducing integral structure before control object is proposed. Firstly, the position loop VSC state equations and equivalent control model are established based on the analyses of the mathematical model of permanent magnet linear synchronous machine (PMLSM). Then it presents a more accurate and comprehensive method to determine the control parameters and the equivalent model parameters. Computer simulation with the motor parameters of a flat type PMLSM verifies the feasibility and effectiveness of the compensator structure. Compared with the conventional VSC, the proposed structure can solve the vibration caused by external disturbance and load variations, and attenuate the chattering effectively. It is concluded through further analyses that the proposed structure can overcome the system oscillations generated by mover mass and permanent magnet flux linkage, and improve the robustness and control precision of the system.
Design and Implementation of a High-Performance PMLSM Control System with Deadbeat Current Control and SMC
Authors: Li Li Yi , Guo Qing Bo , Liu Jia Xi , Wang Tie Cheng
Published: September 2013

The direct-drive PMLSM control system for high-performance positioning systems requires the performance of high dynamic response and strong robustness. The high dynamic PMLSM servo system is satisfied using a digital deadbeat current controller and proposed sliding mode control (SMC). Considering the influence of hardware sampling time delay and inverter delay, the deadbeat current controller can adjust the current loop in 2 PWM cycles and enable the high-bandwidth current control. And based on the proposed SMC, the PMLSM position servo system can provide high dynamic performance and strong robust characteristics. The proposed SMC employs a uniformly asymptotic convergence of saturation function to eliminate the steady-state error and improve the accuracy of servo system. The results of simulation show that the direct-drive PMLSM control system with deadbeat current control and SMC method can acquire fast dynamic response and great robustness.
Improved Model Based Predictive Torque Control Strategy with Fast Dynamic Response for Flux-Switching Permanent Magnet Machines
Authors: Xu Wei , Yang Wen Wu
Published: September 2013

The flux-switching permanent magnet machine (FSPMM) has got great attention by academic researchers during the past couple of years for its merits of strong mechanical robustness, high efficiency, strong thermal dissipation ability, etc. However, for its inherited double salient structure in both stator and rotor, the FSPMM suffers from severe torque and flux ripples at different rotor positions for its variable magnetic resistance, which cannot be solved completely only by electromagnetic optimal design. In order to increase the drive performance of FSPMM, such as dynamic response and stable torque smoothness, an improved model based predictive torque control (MPTC) algorithm is proposed. By using the cost function modulation strategy, the torque and flux ripples of FSPMM are reduced evidently, accompanying with the minimized converter switching frequency and power loss. Comprehensive simulation investigations are finally carried out to validate relevant theoretical analysis.
Study of Intelligent Monitoring System of Low-Voltage Power Distribution
Authors: Sun Mei
Published: September 2013

With the development of domestic low-voltage power distribution technology, people have an increasingly higher demand on the intelligence of low-voltage power distribution cabinet. Combined with the authors several years of experience of practice, this thesis first of all makes a brief analysis of the general situation of power distribution system automation, followed by a key analysis and conclusion of the characteristics of the existing low-voltage monitoring mode. Based on it, digital signal processor with strong floating point calculation ability, a new low-voltage intelligent monitoring system is designed.
Analysis on the Applicability of the Post-Stack Seismic Attribute Recognition Method in the Sand Bodies of the River-Way of Fuyang Oil Layer
Authors: Zhang Xin Rong , Fang Shi , Liu Jin Ping , Lou Yong He
Published: September 2013

The later-period structure of Fuyang oil layer is very complex, and the reservoir mainly consists of river-way sand. The form of the reservoir is narrow and distributed differently, so it is very hard to identify. To accurately predict sand bodies, the sand bodies in the river way are comparatively studied using multiple post-stack seismic attributes, and finally a conclusion is made as follows: the reservoir interpretation technology based on frequency possesses a high spatial resolution and can test the spectrum lateral variation caused by different deposits, and then the plane distributions of the river-way and other deposits are described using equifrequent slices, and the combination characteristics of different deposit rhythmic layers are quantitatively analyzed, and also the thickness change of the river-way can be quantitatively analyzed under the ideal condition. Meanwhile, spectrum imaging is implemented using the tuning frequency of the different thickness of the sand bodies, and the reservoir is identified through the spatial changes of amplitude energy, facies values, and frequency attenuation attributes under the different chosen frequency, so that the spatial discontinuity of the deposits is effectively described. Therefore, it can meet the exploration and development needs of the oil field to a certain extent.
Aeroacoustic Characteristics of Cavity and Effect Study of Mesh on Noise Suppression
Authors: Sun Jing , Yang Guang Jun , Liu Jian Jun
Published: September 2013

To explore the noise suppression effect of mesh on cavity, the wind tunnel experiment is carried out based on the analysis of clean cavity flow characteristics. The meshes are arranged both in the cavity and at the leading edge of the cavity. Through the analysis of pressure distribution on the cavity bottom and the noise spectrum monitored at front and rear walls respectively, noise suppression effects of mesh programs relative to the clean cavity and changes in the flow field are studied, the results show that the mesh inside the cavity has a better noise reduction effect. The work in this paper provides an effective way for cavity noise reduction.
Mechanical Design on Finite Element Method for Ring Laser Gyroscope
Authors: Li Ying
Published: September 2013

The gyroscopes have been used as a suitable inertial instrument for the navigation guidance and attitude controls. The accuracy as very sensitive sensor is limited by the lock-in region (dead band) due to the frequency coupling between two counter-propagating waves at low rotation rates. This frequency coupling gives no phase difference, and an angular increment is not detected. This problem can be overcome by mechanically dithering the gyroscope. This paper presents the design method of mechanical dither by the theoretical considerations and the verification of the theoretical equations through FEM applications. As a result, comparing to the past result, the maximum prediction error of resonant frequency was within 3 percent and peak dither rate was within 5 percent. It was found that the theoretical equations can be feasible for the mechanical performance of dither.
A Stable Dual-Wavelengths Fiber Laser Equipped by an In-Fiber Integrated Michelson Interferometer
Authors: Feng Zhong Yao , Li Ling , Su Dan , Wang Yu Peng
Published: September 2013

In this letter, an in-fiber integrated Michelson interformeteris proposed and experimentally demonstrated. The device consists in the combination of multi-mode fiber (MMF) and a single-mode fiber (SMF) tip which is covered by thick silver film. The MMF excites cladding modes into downstream SMF via the mismatch-core splicing interface. The core-cladding modes are reflected back by the silver and recoupled to fiber core through the MMF. By the reason of fiber-core mismatch and core-cladding modes interference, a well-defined interference pattern is obtained. A stable dual-wavelength fiber laser based on a hybrid gain medium combined with the interferometer filter is realized.
Halftoning Method and Reproduction of Color Gamut in Digital Image Output
Authors: Chen Guang Xue , Chen Qi Feng , Tai Jing Lei , Liu Jiang Wen
Published: September 2013

Image halftoning is the core technique of digital image output, which determines the quality of the color and tonal gradation reproduction. In this paper, the existing halftoning techniques were analyzed and evaluated, such as FM halftoning and AM halftoning, etc. And a new halftoning mode, frequency conversion amplitude modulation (FCAM), was proposed. This method is still based on AM halftoning, but it uses the different screen frequency for halftoning image of the different color version, so as to avoid moiré fringes on the smaller superposition angle. The use of new halftoning model can achieve halftoning image output which is more than 4 colors (such as 6 colors or 7 colors) without visual moirè pattern when overprinting. By the new technique, high-fidelity printing is achieved, and the color gamut of the output image is expanded, and we can get more vivid realistic effect of image transmission. We tested color gamut expansion of 6 colors and 7 colors high-fidelity printing, and obtained the expected conclusion by quantitative analysis.
Parameter Identification of Reaction Wheel Disturbance Model Based WLS-SVR Method
Authors: Wang Yun Feng , Cheng Wei , Xia Ming Yi , Wu Shuang
Published: September 2013

In order to predict the micro-vibration disturbance of reaction wheel, an improved experience model has been provided, which expresses the effect of the reaction wheels natural frequencies being the dominating factor in amplifying the disturbance. WLS-SVR algorithm is applied to identify the parameters of this model. The robust characteristic of this algorithm promises the global optimal estimation can be achieved. Experiment has been set up to measure the disturbance of the reaction wheel. Data achieved from the experiment are used to get the parameters of model and verify the identification results of WLS-SVR algorithm. The results show the improved model describes the properties of disturbance more precisely and the WLS-SVR algorithm can achieve accurately identification results.
Study of the Boundary Layer on a Plate Aerodynamically Induced by Multiple DBD Plasma Based on PIV
Authors: Li Feng , Gao Chao , Zheng Bo Rui , Wang Yu Shuai
Published: September 2013

The boundary layer aerodynamic flow acceleration with one atmosphere uniform induced by multiple dielectric-barrier-discharge plasma actuation were studied based on PIV. Through double actuators alternating discharge, the multiple dielectric barrier discharge mode have been proposed and tested. The efficiencies of the plasma actuators in Pulsed-pulsed, Steady-steady, Pulsed-steady and Steady-pulsed discharge modes were explored. Based on the above results, the boundary layer flow acceleration performance of multiple plasma actuators has been discussed and the more efficient discharge pattern has been proposed. The results of this study indicate that the airflow acceleration effect of multiple plasma actuators mainly occurs in paraelectric direction and the pulsed-pulsed is the more efficient multiple plasma actuation mode.
Research on the Nonlinear Finite Element Analysis of Rubber CVJ Boot
Authors: Zhao Jian Hua , Zhu De Bin , Zhang Rui Bo
Published: September 2013

Rubber CVJ boot is the important part of the car transmission system. Trough crack and surface wear of the CVJ boot are the common failure modes, so the stress distribution simulation of the boot is needed. Acoording to the Mooney-Rivlin model, the definite method of the coefficient for material model was obtained. Based on the software Abaqus, a nonlinear finite element model of CVJ boot was set up. The elements type was hybrid (mixed formulation) C3D4H. The deformation and strength of the boot under working condition were computed. The maximum stress is 11490MPa, located in the first trough and the contact surface of the 3rd and the 2nd crest have more serious wear, which correlate well with the test results. The next work is to optimize boot structure by this simulation model.
Localization Prototype Research of RCC-M Ejector in Nuclear Power Plant
Authors: Qi Yan Li , Xue Yuan , Tian Tian , Chen Xing Jiang , Fang Xi Quan
Published: September 2013

As the key equipment to ensure the stable operation of containment spray system in nuclear power plant, a RCC-M ejector with safe and credible performance is very important to make sure the containment integrality under lose of coolant accident (LOCA) or pipe broken. However, it was purchased from overseas supplier all along because of its special configuration, nonstandard design, severe safety level and small quantity demand. To implement equipment localization, and referring to practical applications of some nuclear plants, a RCC-M ejector is independently manufactured and tested, all performance could meet the requirement according to the test result. The RCC-M ejector is authenticated by experts by China Nuclear Energy Association, and the localization prototype research of this paper has great application and popularization value.
Microstructure Evolution of Ti-6Al-4V Alloy during High Speed Cutting: An Investigation Using Finite Element Simulation
Authors: Cui Tao , Zhao Hong Wei , Liu Chuang , Tian Ye
Published: September 2013

In this paper, a novel model combining the microstructure prediction model and a modified constitutive model of the Johnson-Cook (JC) model was developed and embedded into FEM software via the user subroutine. The chip formation and microstructure evolution in high speed cutting of Ti-6Al-4V alloy were simulated based on the presented model. The results indicated that dynamic recrystallization mainly happened in ASBs, where the grain size had a big decline. According to the variation of cutting temperature and grain size of microstructure, the mechanism of the adiabatic shear bands (ASBs) formation was investigated deeply and concluded that dynamic recrystallization was the root cause of the serrated chip formation.
Influence of Roll Rotational Speed on inside Bore and Lamination Defects in Rotary Piercing Large Diameter Heavy Wall P92 Steel Pipe Process
Authors: Yin Yuan De , Wang Meng Jun , Li Sheng Zhi , Wang Peng Zhan , Wang Xiang Dong , Li Guo Tao
Published: September 2013

To investigate the influence of different roll rotational speeds on tendency of inside bore and lamination defects of large diameter heavy wall seamless P92 (9Cr-0.5Mo-1.8WVNb) steel pipe pierced by two-high rotary piercing process, with the aid of commercial FE code MSC. SuperForm, 3D thermo-mechanical coupled simulations were presented. The damage field of the rolled piece during rotary piercing process, and the tendency of forming inside bore and lamination defects were analyzed using Oyane ductile fracture criterion. The results show that When roll rotational speed increases from 7rpm to 11rpm, the maximal damage characteristic value decreases from 0.4279 to 0.3340 in center area of rolled piece in front of the plug, but which increases from 0.3780 to 0.4858 in a certain depth zone (15~25mm) adjacent to the internal surface of the rolled piece contacting with the front end of the plug. With the increase of roll rotational speed, the tendency of forming inside bore defects of rolled piece reduces, but the tendency of forming lamination defects increases. Therefore, there exists a critical roll rotational speed to make the tendency of both inside bore and lamination defects reduce. This study provides scientific basis for formulating reasonable rotational speed schedule to prevent or reduce inner overlap and lamination defects.
Mirror Finishing Method of Electrochemical Polishing and Mechanical Grinding for Cold Rolling Rollers
Authors: Han Dong Gui , Li Yong Feng , Fu Jun , Liu Hong Hai , Chen Shu Jian
Published: September 2013

Electrochemical polishing (ECP) is a promising approach to finishing surface to achieve high quality of surface. However, it cannot satisfy requirements of mirror finishing yet. In this paper, a mirror finishing method for cold rolling rollers is proposed. The whole process of the surface finishing can be divided into two phases: electrochemical polishing and mechanical grinding. An anodic film is formed exception for anodic dissolution during ECP. A small amount of the anodic film and metal material are removed by abrasive paper in mechanical grinding. Activated metal surface is exposed again and dissolved in electrochemical reaction after mechanical grinding. Residual of anodic film protects rollers. It is a cyclic process of mirror finishing. Experimental results showed that a mirror finishing surface of up to Ra0.02-0.05μm can be obtained by using this method and that it is effective and efficient.
The Verification of Material Plastic Flow at Optimal Warm Forging Temperature Using Computer Simulation
Authors: Kapustova Maria
Published: September 2013

Warm forging is most commonly used for production of die forgings which are manufactured by means of precise forging. As compared to cold forging, warm forging enables to reduce forging forces size considerably. Development of warm forging technology is connected to formability and plasticity research of forged material at warm temperatures. This contribution brings a methodology for optimal forging temperature determination from recommended interval of warm temperatures used for chromium-manganic steel 16MnCr5. The given steel is appropriate for case hardening and precise die forgings production. For the purpose of verification of steel forgeability at the recommended interval of warm forging temperatures 600, 650, 700 and 750 °C technological test of upsetting according to Zidek is used. The main factor of plasticity for optimal warm temperature selection from examined temperature interval is value of reduction of area that was determined by tensile test. Numeric simulation of forging process in closed die confirmed correct plastic flow of steel 16MnCr5 at recommended forging temperature 700 degrees of Celsius.
The Material Nonlinear Analysis of Bioprosthetic Heart Valve on Suture Densities
Authors: Zhang Xia , Yuan Quan , Zhang Jun , Huang Xu , Cong Hua
Published: September 2013

In order to investigate the effect of suture density on the dynamic behavior of bioprosthetic heart valve with nonlinear material and improve long term durability of bioprosthetic heart valve, we establish the ellipsoidal leaflets and paraboloidal leaflets models via computer aided design. Based on the parametric models of the heart valve, four kinds of suture density (100,70,50 and 35 suture points on the attachment edge of the bioprosthetic heart valve) are analyzed by using finite element method. The finite element analysis results are compared with each valve model. It shows that suture density has a significant effect on the dynamic behavior of the bioprosthetic heart valve, which lead to different stress peak values, different stress distributions and deformation. The finite element analysis of the BHV could provide direct and useful information for the BHV designer.
Prediction of Surface Roughness in the End Milling Machining Using Fuzzy Rule-Based
Authors: Mohd Adnan M.R.H. , Mohd Zain Azlan , Haron Habibollah
Published: September 2013

In the experiment, 24 samples of data has been tested in real machining by using uncoated, TiAlN coated, and SNTR coated cutting tools of titanium alloy (Ti-6Al-4v). The fuzzy rule-based model is developed using MATLAB fuzzy logic toolbox. Rule-based reasoning and fuzzy logic are used to develop a model to predict the surface roughness value of end milling process. The process parameters considered in this study are cutting speed, feed rate, and radial rake angle, each has five linguistic values. Nine linguistic values and twenty four IF-THEN rules are created for model development. Predicted result of the uncoated, TiAlN coated, and SNTR coated has been compared to the experimental results, and it gave a good agreement with the correlation 0.9842, 0.9378 and 0.9845, respectively. The differences of the uncoated, TiAlN coated, and SNTR coated between experimental results and predicted results have been proven with estimation error value 0.00025, 0.0015 and 0.0008, respectively. It was found that by applying SNTR coated cutting tools with the recommended combination of linguistic values might gave best surface roughness values.
Microstructure Refinement of Pure Aluminum by Inoculation with Stainless Steel Powders
Authors: Tsukamoto H. , Komiya Yoshiki , Oshima N. , Sato Hisashi , Watanabe Yoshimi
Published: September 2013

The aim of this study is to investigate efficiency of stainless steel powder inoculation into pure aluminum for microstructure refinement. Refiners consisting of pure aluminum powder (powder size: 106~180m) and stainless steel powder (powder size: 25~53m) have been fabricated through spark plasma sintering (SPS). The stainless steels used in the study include SUS304L, SUS316L and SUS434L. SUS 304L powder has achieved a great grain refinement in cast aluminum, for which fading phenomenon has been considerably avoided. SUS316L and SUS434L powders develop fine dendrite structures, which can lead to high hardness of cast aluminum.
Numerical Simulation Study on Advanced Water Injection for Fuyang Ultra-Low Permeability Fractured Reservoir
Authors: Kou Hui Hui , Liu Xian Gui , Xiao Han Min , Sun Ling Hui , Hou Dong Dong , Zhou Li
Published: September 2013

According to the features of low porosity and low permeability fracture as well as small scale of channel development, frequent sedimentary facies changes of planar sandstone, poor connectivity, large variation of sequence thickness and great development difficulties for oil layer in Fuyang Oilfield. In this paper, on the basis of fully considered of fracture features, built a more accurate 3-D geological model. And on the basis of the history matching, determined the formation pressure maintenance level under different injection-production ratio and rational water-flooding timing by the simulation of the different programs in the process advanced water injection development. The results show that: the reasonable injection-production ratio of Fuyang oil layer is 1.4, and the rational water-flooding timing is three months after advanced water injection. This provides theoretical guidance for the large-scale development of Fuyang oil layer, and also provides the technical basis for the developing of the other low permeability fractured oil field by advanced water injection.
Studies on Tensile and Water Absorption Properties on Kenaf (Hibiscus Cannabinus) Fibre Mat/Polyester Composite Using Chemical Treatment
Authors: Mohamad Nurul Azman Mohammad Taib , Masitah Abu Kassim , Mohd Ariff Jamaludin , Tayibbah Ismail
Published: September 2013

This research investigated the tensile and water absorption properties of kenaf fibre mat/polyester composites. Treatment using acetylation method has been introduced to improve the properties of product manufactured. The effects of acetylation treatment with three variations of time that were 1, 4 and 24 hours on the kenaf fibre mats were investigated. The MOE of the tensile of treated fibre mat/polyester composite for 1 hour was the highest with value 4589.61 MPa. The tensile strength of treated fibre mat/polyester composite for 4 hours was the highest with value 0.6213 MPa. For water absorption test, the results showed that fibre mat/polyester composite with treatment duration for 1 hour had the lowest water absorption that was 1.23% compared with treatment duration for 4 hours and 24 hours. For overall it can be concluded that the treatment duration of 1 hour was recommended for acetylation method when compared with 4 hours and 24 hours duration treatments. Using acetylation treatment on the kenaf fibre mat/polyester composites was showed improvement on composite and was recommended in short duration of treatment.
Construction of Eukaryotic Expression Vector and Expression on Mycobacterium bovis ag85a and mpb70 Genes
Authors: Hou Shuang , Wang Chun Fang , Zheng Yan Ru , Guan Jia Ning , Lin Jia Ming , Gao Da Ming , Gao Yun Hang , Ma Hong Xia , Jiang Xiu Yun
Published: September 2013

Based on the polymerase chain reaction (PCR), ag85a and mpb70 Fusion gene of Mycobacterium bovis were ligated and cloned into pMD18-T, then recombinant plasmid pMD-85a-70 was constructed. pMD-85a-70 and pVAX1-BMS were digested by double enzymes HindIII and EcoRI, the purified ag85a-mpb70 was subcloned into pVAX1-BMS, then recombinant plasmid pVAX1-BMS-85a-70 was constructed and transient expressed in Marc145 cell. These results laid solid foundations for further studies on ag85a-mpb70.
Synthesis of Unique Structures of Carbon Nanotube at Anodic Aluminum Oxide Template
Authors: Kasi Jafar Khan , Kasi Ajab Khan , Bokhari Muzamil , Afzulpurkar Nitin
Published: September 2013

Carbon nanotube (CNT) is one of the most attractive nanomaterials which may be used in many potential applications of nanotechnology due to its excellent mechanical, electrical and thermal properties. We demonstrated the fabrication of carbon nanotube at the surface of anodic aluminum oxide (AAO) membrane by chemical vapor deposition (CVD) method. Acetylene was used as a hydrocarbon source and Fe as catalyst. CNT was synthesized at different temperature. The iron catalyst was confined in the holes of the AAO membrane. A variety of carbon structures such as nanotubes, helices, spiral, and hook-like curved shapes in the range of micrometer were synthesized. High graphitic multiwall carbon nanotube (MWCNT) was found at 700-750°C temperature.
Effects of Growth Time on Morphologies of ZnO Nanorod Arrays
Authors: Zhao Kang , Wu Zhi Ming , Tang Rong
Published: September 2013

well-aligned ZnO nanorod arrays (ZNRAs) grown on the ZnO seed layers coated p-silicon (p-Si) substrates in various times from 1.5 to 5 hr have been fabricated from aqueous solutions at low temperature. Morphologies, crystalline structure and optical transmission were investigated by a scanning electron microscope (SEM) and X-ray diffraction (XRD), respectively. The results showed that ZNRAs grew vertically from the substrates, having uniform thickness and length distribution, the average diameters and length of ZnO nanorods increased with increasing growth time below 3 hr. The XRD results showed that ZnO nanorods were wurtzite-structured (hexagonal) ZnO.
Effect of Drawing Tubes without Interoperation Recrystallization Annealing on the Orientation of Boundaries Grain – Longitudinal Direction
Authors: Ridzoň Martin , Závacká Anna
Published: September 2013

well-aligned ZnO nanorod arrays (ZNRAs) grown on the ZnO seed layers coated p-silicon (p-Si) substrates in various times from 1.5 to 5 hr have been fabricated from aqueous solutions at low temperature. Morphologies, crystalline structure and optical transmission were investigated by a scanning electron microscope (SEM) and X-ray diffraction (XRD), respectively. The results showed that ZNRAs grew vertically from the substrates, having uniform thickness and length distribution, the average diameters and length of ZnO nanorods increased with increasing growth time below 3 hr. The XRD results showed that ZnO nanorods were wurtzite-structured (hexagonal) ZnO.