bluuebunny/crossref_metadata_2025 huggingface dataset:
High Efficiency 500W RF Generator
Authors: Qin Wei , Li Yong Tao , Li Ying Jie , Xu Xiao Ping
Published: November 2011

In the previous literature about RF generator, Efficiency of output of RF generator can reach 60-70 percent. In this paper, a new 500W RF generator with high efficiency and high stability is designed and fabricated for plasma applications. The efficiency of a power amplifier in the RF generator is improved by using Class-E amplifier. The Class-E power amplifiers described here is based on a load network synthesized to have a transient response which maximizes power efficiency even if the active device switching times are substantial fractions of the AC cycle. For that circuit, the author measures 73 percent efficiency of output of RF generator at 13.56MHZ and 478W output from DE375 MOSFET. The main reasons of power dissipation mainly are analyzed, and some measures are taken to improve them by the optimization principles and experimental results and the efficiency of the power output can reach above 70 percent.
Design of Remote Transmission System for Wireless Heat Metering
Authors: Wang Xiao , Ma Ru Jian , Zhang En Ping
Published: November 2011

A design scheme is proposed in this paper for heat metering remote transmission system based on the Xbee Pro module. Wireless network technology is used in the scheme. A dynamic monitoring, control and transmission network is composed by the wireless network system and the computer in the monitoring and control center. The real-time data detected from heat metering system can be transmitted and monitored. Xbee Pro module and MSP430FW427 single-chip micro-computer are used in the nodes or terminals of the system. The self-provided functions and modules of the components are taken into sufficient consideration in the design to make the system performance as superior as possible and the system structure as simple as possible. In this way, the transmission system with low power consumption and simple structure is achieved.
The Optimal Controller Design of Zero Steady-State Error for Nonlinear Systems with Composite Disturbances
Authors: Gao De Xin , Wei Rui
Published: November 2011

This paper considers the optimal rejection with Zero Steady-State Error for nonlinear systems with step and ramp composite disturbances. Firstly, the nonlinear system model with composite disturbances is transformed into linear system with disturbances, then we construct an augmented linear system without disturbances. With respect to the quadratic performance indexes of infinite horizon, consequently, the problem of disturbance rejection with zero steady-state error is transformed into the problem of designing an optimal controller for the augmented plant without disturbances, which can eliminate static error. Thus the disturbances can unfold of the signal through the Taylor series for the form of polynomial function of time, and obtain optimal controller design approach to eliminate the general disturbance. Finally, a practical example is given to illustrate the effectiveness of the theory.
Active Power Smoothing of Wind Generator Based on Wind Speed Prediction and Inverse-System
Authors: Wang Xiao Lan , Wu Jiao
Published: November 2011

Active power smoothing of wind generator is very important to the utilization of wind energy. One-step ahead prediction of wind speed with the inverse-system is proposed in this paper. Wind generator is simplified as first order dynamic model. An inverse-system is designed to cascade with the model. Kalman filter and ARIMA models are used to predict the wind speed one-step ahead. The predicted wind speed is the input to the cascade system. The simulation shows that the fluctuations of the torque, the active power and the pitch angle are decreased effectively.
Determination of Key Technical Parameters of Special Hydraulic Turbine for Cooling Tower
Authors: Li Yan Pin , Nan Hai Peng , Duan Kai Chuang
Published: November 2011

The author analyzed the working environment of special hydraulic turbine for cooling tower basing on the difference between the special turbine for cooling tower and the conventional power turbine. The former works in series pressure system and the water head determined by the pipeline resistance and the property of circulating water pump of cooling tower. It is the key to transform the cooling tower system successfully and save energy to build up a series special theories which include the specific speed of turbine for cooling tower, the type of turbine, the parameters selection, the design of the flow passage and runner of turbine by effectively transforming the conventional power turbine theory to the special turbine of cooling tower.
Research on the Pumping Unit Model Driven by Linear Motor
Authors: Ma Wen Zhong , Sun Jin Yan , Zhang Hong Mei , Tian De Bao , Pang Hong Fei
Published: November 2011

With superior performances, Linear motor driven pumping unit becomes the electrical control of the focus and emphasis of the recent oil field equipment. Against the beam pumping unit motor efficiency, low power factor and stoke that difficult to regulate, this paper proposes new research programs about energy-saving line pumping systems by linear motor driven source. Paper Studys the mechanical model of linear motor in detail, using MATLAB / SIMULINK, a simulation model is analyzed. At the base of vector control of revolving induction motor, we established the linear motor control system. Theoretical analysis and computer simulation results show that the speed control system has good performance, response characteristics of the electromagnetic force, and demonstrate the proposed mathematical model and control method.
Research on Knowledge-Based Injection Mould Project Design System
Authors: Han Li Fen , Zhong Shou Yan , Ding Wei Feng , Liu Tan Xiang
Published: November 2011

The intelligent design technology based on the Expert System (ES) was applied into injection mould design. The experts’ knowledge and experience related to the injection mould project design (IMPD) was expressed in the form of production rule. The knowledge base of intelligent project design of injection mould was constructed. The knowledge automatic reasoning via CLIPS (C Language Integrated Production System) knowledge deducing machine was realized. The achievement of the injection mould project’s intelligent design was reached. The research on the injection mould intelligent design based on CLIPS was made. The intelligent design system for injection mould project (IDSIMP) was developed. The injection mould design project could be provided to the injection mould design engineers via the system. The system is of better application value on engineering.
The Optimization of ITD in Direct Air-Cooled System
Authors: Chen Li Jun , Xu Chao , Wang Ying , Mi Li Jun , Shi Xing Cai
Published: November 2011

In order to improve the technical economy of direct air-cooled system, based on the thermodynamic model of the air-cooled system, taking the annual total cost as the objective function, the face velocity of air and the ITD (initial temperature difference) value as parameters, this article has researched the optimal ITD of direct air-cooled system in theory, and given the uncertainty analysis in the end to reflect the influence of economic parameters. The results shows that the technical economy of direct air-cooled system can achieve optimal under the condition of economic parameters change. Thus, the results of studying will provide helpful guidance for the optimization of direct air-cooled system.
Research on the Multi-Parameters Matching Control of the Cooling System for the Diesel Engine on the Numerical Simulation Technology
Authors: Sun Zuo Yu , Li Xiang Rong , Guo Liang Ping , Zhang Xue Yan
Published: November 2011

For the growing importance of future emission restrictions and the expanding requirement for a better fuel economy, the internal combustion engines are forced to be improved for the high strengthening direction. However, the heat loads of the engine is increasing according to the increasing of engine speed and power density, hence, the cooling system is faced to more challenge. For the cooling system is one of the key system which has more effect on the engine efficiency, fuel economy, and exhaust heats; optimize the matching control cooling system becomes one of the key technology to improve the engine performance. In this paper, several overall schemes of the cooling system are analyzed and discussed, and then one design scheme is determined to the optimal for the current diesel engine. A whole engine system is established by the software GT-Power, and the cooling system in the engine system is established by GT-Cool based on the above optimal scheme. During the simulation, the influence on the heat dissipating capability brought by the control parameters, injection advance angle, power, and torque are investigated. At last, the requirement of the heat released under full conditions is analyzed, and the relationship of the fuel consumption and the control parameters is investigated.
Research on Parametric Design Method of Combustion Chamber on Diesel Engine
Authors: Shang Yong , Liu Fu Shui , Li Xiang Rong , Wu Jing
Published: November 2011

One method of parametric design on combustion chamber is used in this paper. Several independent geometrical parameters of ω type and double swirl combustion chamber are brought forward. Different series of ω type and double swirl combustion chambers have been designed by using this method. The effect of the independent geometrical parameters on the performance of diesel engine has been studied by using CFD code AVL FIRE. According to this method of parametric design and calculation result, two pistons with ω type and double swirl combustion chamber has been designed with the target of the highest indicated heat efficiency. The test result shows that, contrasting with ω type chamber, BSFC and main combustion duration of double swirl combustion chamber is lower by 7.5 and 6.9 percent respectively, while indicated heat efficiency is 7.1 percent higher. And the calculation result has coherence with the experiment. It is proved that the method of parametric design on combustion chamber can satisfy the requirement of designing. At the same time, this method can be extended to design other combustion chambers.
Design and Application of Long Distance Oil & Gas Pipeline Stress & Strain Monitoring Sensor
Authors: Ma Yun Bin , Cai Yong Jun , Tan Dong Jie , Hu Zhi Xin
Published: November 2011

As Oil & Gas Pipeline of Long Distance has potential mechanical risks caused by geologic hazards, based on sensing technique, Fiber Bragg Grating (FBG) strain sensor, for which unstressed grating temperature compensation method is adopted, is designed to solve problems of FBG temperature and strain cross sensitivity. According to experimental tests, strain sensitive coefficients of the sensor before and after sticking on pipeline sample are 1.20 pm/με and 1.09 pm/με in separate. Finally, applied to a landslide area for monitoring pipeline stress, the sensor got the impact of Wenchuan Earthquake on May 12, 2008 on the pipeline.
Application of FSK Technology in Welding Machine
Authors: Qian Li , Zhang Shan Shu , Hao Feng Xiao
Published: November 2011

The remoter of welding machine transfers control signals by technology: FSK in electric power and MCU, it overcomes the shortcomings of wire controller. It indicates that the remoter can be used more conveniently, the control signals transfer more accurately, and has better anti-jamming by the application of FSK technology.
Application of RBF Neural Network in Dynamic Weighing
Authors: Jiang Qing , Shen Xiao Qian , Cai Jin Hui , Yao Yan
Published: November 2011

In order to improve the dynamical respond of the weighing system and to meet the demand of rapid weighing, a new method based on radial basis function neural network (RBFNN) is introduced in this paper. The dynamic system is described as a network and the output values of steady state are predicted by an on-line modeling before the platform has settled to the steady state. The sample weight is calculated according to weighted moving average. The experimental results proved that the neural network method in this paper can be used to effectively reduce the weighing time and to increase the accuracy simultaneously.
A New Method of Rolling Prediction for Gas Emission Based on Wavelet Neural Network
Authors: Pan Yu Min , Zhang Xiao Yu , Xue Peng Qian
Published: November 2011

A new method of rolling prediction for gas emission based on wavelet neural network is proposed in this paper. In the method, part of the sample data is selected, which length is constant, and the data is reselected as the next prediction step. Then a wavelet neutral network is adopted to prediction which input data is rolling, the sequence model of rolling prediction is thus constructed. Simulation results have proved that the method is valid and feasible.
Model and Auto Take-Off Control Law Design of Unmanned Aerial Vehicle
Authors: Song Hui , Chen Xin
Published: November 2011

The Unmanned Aerial Vehicle (UAV) has special dynamical characteristics in ground motion different from that of flight in the airborne. The forces and moments on the ground to the UAV differ during taxiing, according to the different mechanical and aerodynamic characteristics. An all-states nonlinear model is established by studying on a sample UAV. Rotation speed and lift off speed is determined, finally a control law including longitudinal and lateral control for automatic take-off is designed. Results of simulation show that the model and control scheme can not only join the ground taxiing and flight in the airborne smoothly, but also has a high value in realizing engineering project.
Study and Implementation of Fault Diagnostic Algorithms on Hydraulic Power Cart for Aircraft
Authors: Zhang Huai Bin , Yang Hua
Published: November 2011

According to the lack of simple, backward and low precision in fault diagnosis on hydraulic power cart for aircraft, an efficient vehicle fault diagnosis system on hydraulic power cart for aircraft is developed based on embedded technology. This system can identify the cause of the faults quickly and accurately according to the data collected in the spot and real-time analysis using expert system, the results show it greatly improves the efficiency and accuracy of fault diagnosis on hydraulic power cart for aircraft.
Modeling of Multi-Agent System for Drilling Simulation
Authors: Wang Wu Li , Wang Yan Jiang
Published: November 2011

In view of the characteristics of the oil drilling process and the existing problems of traditional simulation system, a new distributed drilling simulation model was established based on Multi-Agent system (MAS) technology. By means of autonomous, cooperative and reactive characteristic of Agent, the drilling laws and phenomenon can be reflected promptly and accurately under any circumstances. The MAS modeling for oil drilling simulation, the structure and knowledge representation of each Agent and the communication among Agents are described in detail. Finally, an Agent-based normal drilling well control simulation training example was given. The simulation results show that the simulator based on Multi-Agent system has better performances than traditional drilling simulators, and enhances the integrated training function of the drilling simulation system.
Development and Design of Dance Robot Based on Single-Chip Microcomputer AT90S8535
Authors: Han Yue Mei
Published: November 2011

With the development of robot technology some robots have been seen in the field of entertainment. Dance robot’s mechanical structure is the motion mode with several free degrees drove by electric motor. The blocking idea was impenetrate in hardware design and the CPU was high-quality single-chip AT90S8535.The technology PWM with width modulation combined with three subprograms and main program were adopted in the software so that the dance robot can complete all the action arranged in advance.
The Software Design and Implementation of a Real-Time Automatic-Tracking System
Authors: Liu Xin Yu , Gu Bo
Published: November 2011

Aiming at the low degree and the poor real-time quality of the old monitoring system at present, this paper develops direction discrimination and velocity prediction algorithm in order to detect the parameters of moving object and then to control camera to track the abnormal moving target. Field test and operation prove that the system has a good tracking performance and stability.
Infineon Microcontroller Based Frequency Converter Design
Authors: Lv Xue Cong , Li Wen Feng
Published: November 2011

In this paper, we implement a real-time detection and automatic control design for AC-DC-AC converter based on XC878M microcontroller unit (MCU). By generating the sinusoidal pulse width modulation (SPWM) signal directly using the microcontroller, the hardware circuit is simplified and the power factor and efficiency of the system is greatly improved. Further, frequency conversion techniques are applied into our design. After the high frequency modulation and compressed the high frequency harmonics, the proposed design can produce high-quality voltage waveform, thereby decreasing the loss of the converter.
Intelligent Autonomous Navigation System for the Wheeled Mobile Robot
Authors: Dat Truong Minh , Neil Nieh Yu Feng , Ricky Lee Min Fan , Khotimah Wijayanti Nurul , Dat Luu Quoc
Published: November 2011

An intelligent behavior control system for an autonomous mobile robot operating in an unstructured environment with sensor uncertainties is proposed. This study focuses on implementing and improving the methodology from Motlagh et al. [7] on a two-wheeled P3DX mobile robot. Motlagh et al. verified their design with computer simulation. When applying it on a real robot platform, we noticed some problems and improved the design using sensor selection strategy, safe rule and target switching strategy. The proposed sensor fusion architecture introduces two additional sensors, a laser range finder on the robot and an omnidirectional CCD camera on the ceiling, to improve the reliability of the sensing capability of P3DX mobile robot. The target switching strategy is used to guide the robot out of a dead zone and reach the target by creating a virtual target. Results of the experiments with the U-shaped and subspace dead zones are presented. These results proved that the target switching strategy successfully dealt with the loop path problem in the dead zone.
Trajectory Control Using Linear Control System on Mobile Robot
Authors: Chang Kuei Ying , Hsu Huai Jen , Alexandra Pendry , Ricky Lee Min Fan
Published: November 2011

A lot of studies have been conducted and published on how to control the wheeled mobile robot to reach the desired target smoothly and many simulation results have been presented. However, very few of the control theorems have been applied on a real mobile robot platform to test the feasibility. This paper focuses on the experimental validation by applying the kinematic model and the control law suggested by Siegwart et al [6] on a nonholonomic wheeled mobile robot. The omni-directional camera mounted on ceiling is used to capture the initial position of robot and monitor the trajectory. Our experiment results proved with the proposed control law, the mobile robot can reach the final goal and stop.
Research on Management Information Platform of Dynamic Water Rights Based on Grid Technology
Authors: Feng Chen , Zhang Chen , Xie Jian Cang , Wang Ni
Published: November 2011

For achieving the management and monitoring platform of dynamic water rights based on grid technology, According to the theories of water rights, water market and the basic principles of software technology. Through the framework and structural analysis, hierarchical analysis and task analysis combining the rich program language, Constructing the thinking of system's portal and dispatch center. Achieve the platform's main functions of information management and user management. Solve effectively water rights information sharing and idle resources allocation and utilization of real-time problems. Increased information sharing and scientific configuration in the transfer of dynamic water rights. Provided a base platform for realizing information management of water rights and water markets.
Study and Application of the Variable Torque Slipping Clutch with Skewed Rollers
Authors: Feng Ming , Xing Wei , Lian Jun Wei , Yan Guang Rong
Published: November 2011

The Variable Torque Slipping Clutch with Skewed Rollers is a new type of power transmission component, which combines both clutch and bearing functions, and has broad application prospects in industrial products. This paper describes its configuration, operating principle and characteristics. The present situation of its study and application at home and abroad and key issues needed to be further studied are also introduced.
Research on FFU Power Supply Based on Variable Universe Adaptive Fuzzy Control
Authors: Wang Yi Wang
Published: November 2011

There are serious nonlinear, variable strongly coupling characteristic in traditional fan filter units (FFU) motor, and its electromagnetic relationship is hard to analyze. In order to solve these problems, and because the FFU motor has serious nonlinear, variable strongly coupling characteristic, a control system for FFU motor speed regulation is carried out based on the variable universe fuzzy theory, which can modify universe according to the change of inputs. The simulation analysin and experimental results are prposed and verified the power supply can more effectively achieve the FFU fan motor variable frequency speed regulation control than traditional methods and the performance of the proposed control strategy.
The Analytical Solution of Single Pipe Piles under Axially and Laterally Free Loads
Authors: Wang Zhe , Xu Si Fa , Wang Guo Cai , Zhang Yong
Published: November 2011

The analytical solution of a single pipe piles under axially and laterally loads is presented, when the laterally loads is optional free load. As piles foundations are becoming a preferred foundation type, piles usually work under simultaneous axial and lateral loads in engineering. To analyze the function of free loads to pipe piles under inclined loads conditions, in the basis of ‘m’ method, deformation differential equation of elastic piles under inclined loads is established first in the paper with analytical method. Differential equation has two parts in according to the piles in the earth or in the air, and lateral deformation, obliquity, moment; shearing force of the piles can be gotten respectively by soluting equations. In the end of the paper, influences of several parameters is analyzed of the top axial loads, the top lateral loads and the free loads, and their influence curves are given.
Analysis of Piles Subject to Axial Load and Lateral Soil Movement
Authors: Zhang Zeng Feng , Li Jing Pei
Published: November 2011

A three-dimensional nonlinear elastic-plastic finite element method had been developed to study the bending behavior of piles subjected to axial load and lateral soil displacement. The influence of the lateral soil displacement, axial load level and the cap of piles were studied and variety law of the bending behavior was presented. The study showed that the bending moment increased with the lateral soil displacement. The displacement at the soil surface and the maximum bending moment of pile also increase with the axial load. The cap of piles has a great influence on bending moment and displacement of pile group.
Improvement of Local Decrease in Material Thickness on Fuel Filler Tube
Authors: Kamei Nobuyuki , Watari Hisaki
Published: November 2011

A growing demand for lightweight products has been brought about by the rapid development of new automobiles in order to reduce fuel consumption, since the global environment conservation meeting at Kyoto. One of the keys to reduced fuel consumption is to utilize high-strength, light materials like stainless-steel, high-tensile strength steels and magnesium alloys, which are difficult to form due to their material characteristics compared to normal steel tubes. The purpose of this paper discuses the development of our new pressing technology that forms a relatively high-strength and light weight stainless-steel tube which is SUS436 with surface screw threads. Our new press-forming process was tested in order to obtain accurate screw threads on stainless-steel tubes. Finite element simulation and a 3-D digitizer were used to measure the accuracy of tubes manufactured by the proposed pressing method. It was proved from FEM simulation and a 3-D digitizer measurement that the proposed press-forming method decrease tube thickness more effectively than conventional roll-forming technology. As a result, the maximum decrease in material thickness produced by conventional roll-forming process was 40%, but the maximum decrease in material thickness produced by our press-forming process was 20%. Especially the processing by four outer dies and two inner dies is better as for material thickness than the processing by six outer dies and three inner dies.
Powder Mixed Micro Electro Discharge Milling of Titanium Alloy: Investigation of Material Removal Rate
Authors: Mohammad Yeakub Ali , Rahman Nur Atiqah Binti Abdul , Aris Erniyati Binti Mohamad
Published: November 2011

This paper presents effects of silicon carbide (SiC) powder in dielectric fluid of micro EDM on material removal rate (MRR). The aim is to identify the optimum level of SiC powder concentration and other micro EDM parameter for higher MRR. The work material was titanium alloy (Ti-6Al-4V) machined with tungsten carbide (WC) electrode by varying two machining parameters SiC powder concentrations and discharge energy. By using two factor four level factorial design of experiment, sixteen experiments were conducted. Data were analyzed by Design Expert® software. In this experimental investigation, maximum MRR of 7.3 µg/min was obtained for 24.75 g/l SiC powder concentration and 56.77 µJ discharge energy. The analysis of variance revealed that the SiC powder concentration in dielectric fluid on micro EDM has significant influence on MRR Ti-6Al-4V titanium alloy.
Investigation of Static Failure for Cemented Carbide Cylindrical End Mill
Authors: Khine Ei Ei , Zhang Yi Du , Wu Qiong
Published: November 2011

Investigation of the cutting tool failure is one of the important factors in order to optimize the cutting parameters. This paper studies the cutting tool stresses (maximum principal, maximum shear and von Mises) at the shank and at the tip using three failure theories. These stresses are analyzed by means of the finite element method using MSC patran/nastran software and the experimental method using electrical-resistance strain gages. The comparison of the stresses obtained from these two methods for different feed rates and different rotation speeds are depicted in figures.
The Using of Anti-Sulfur Drill Pipe in High Sulfur Oil-Gas Field
Authors: Li Fei , Feng Ding , Wang Jia Wei , Gao De Li
Published: November 2011

H2S existed in some oil-gas field, resulting in many drill pipe hydrogen embrittlement and stress corrosion cracking accident during the drilling, causing huge losses, particularly during blowout and pipe fall into the bottom caused by hydrogen embrittlement, would lead to serious accident .There were a lot examples in history, in view of the situation, this paper analyzed of the mechanism of the hazards of H2S to the drill pipe, proposed the technical conditions and using requirements to select anti-sulfur drill pipe. After field using, selecting the proper types of anti-sulfur drill can improve the safety of drilling. According to field application summed some attention in the process of using the anti-s drill issue to be aware of.
Backstepping Adaptive Control of NC Tool Crossbeam Magnetic Levitation System
Authors: Liu Chun Fang , Chi Qing Guang , Wang Li Mei , Guo Qing Ding
Published: November 2011

At the moving crossbeam levitation system of the gantry NC machine tool, backstepping adaptive mode control was proposed to achieve the high precision and steady levitation of the gap due to the effect of the cutting force on magnetic levitation system. Considering that the speed state variable is nonmeasurable, a state filter K was designed to estimate the parameter on line. And then the adaptive backstepping controller is designed for the nonlinear magnetic levitation system. The system can achieve the global trajectory tracking of the output because of its unique structure and the capacity to the system disturbance, while all the signals of this closed-loop system can remain bounded via the Lyapunouv theory. The simulation results show this method can keep the stability of levitation system. Meantime, this controller has powerful ability of suppressing disturbance and high rigidity.
Design about Monitoring and Diagnosis System Structure of Rotating Machinery Based on LabVIEW
Authors: Lu Yan Jun , Liu Ying
Published: November 2011

Rotating machinery becomes more and more large and complex, increasingly high degree of automation. Rotating machinery fault could easily lead to heavy losses. Therefore, the requirements of monitoring and diagnosis systems are increasing high. In this paper, the superiority of the application of virtual instrument on condition monitoring and diagnosis system building in the industrial production is described. And then, the rotor system as the main research object, a rotating machinery condition monitoring and diagnosis system is built by using Virtual Instrument technology. At the same time, the structure of the condition monitoring and diagnosis system is discussed. Besides, data acquisition process and fault features recognition method are discussed as well. Finally, the correctness and accuracy of fault detection are verified by means of experiments.
Analysis for Obstacle Negotiation Capability of Wheel-Legged Robot
Authors: Tian Hai Bo , Fang Zong De , Meng Fan Jun , Yang Xiao Fang
Published: November 2011

Obstacle negotiation capability is important to a mobile robot. A wheel-legged robot with symmetrical structure was presented It has four independent wheel-legged articulations which can generate a series of conFigureurations to improve its trafficability. The obstacle negotiation capability of the robot was studied. Its step-climbing process was described, and the geometrical and dynamic model for the process was built. Based on comprehensively considering geometrical and dynamic constraints, the method to work out the maximal step height that the robot can get across was brought forward. Then the method to work out the maximal slope angle was also provided. Finally the experiment to verify the above methods was done. The research mentioned above would provide a theoretical foundation to improve the robot’s adaptability in complicated environments.
Analysis on Variability of Mechanical Parameters in the Process of Rock Damage
Authors: Tan Wen Hui , Zhang Lei , Gao Dan Qing , Li Ya Liang
Published: November 2011

How the mechanical parameters of rock change with the development of joints and fractures is still a puzzle. It is hard to measure rock joints accurately at present. Resistivity is an important parameter of rock and its value can reflect the degree of fragmentation of rock. A new method combining measurement method of Young’s modulus with resistivity survey method is proposed in this paper. To determine the variation of mechanical parameters in the process of rock damage, the uniaxial, tri-axial compression tests and resistivity survey on rock specimens are done. The results showed that the values of resistivity were continuously increasing, but Young’s modulus and mechanical parameters were decreasing in the process of rock damage. The relationships between resistivity and mechanical parameters are established based on the experiments in the process of rock damage. Therefore, the damage state of rock and the change of mechanical parameters of rock can be determined according to the variance of resistivity. The study is helpful for design and real- time stability evaluation on rock engineering.
Oscillation Characteristic of Single Free Piston Engine Generator
Authors: Tian Chun Lai , Feng Hui Hua , Zuo Zheng Xing
Published: November 2011

An oscillation model of a single free piston engine generator which is coupled with a linear generator is presented in this paper. Based on the dynamics and energy equilibrium, the oscillation model is described by the mass spring damping system. It demonstrates that the generator could be regarded as a single freedom self-exited vibration system. The excitation is the periodical combustion in the cylinder. And the system reaches a limit loop after several cycles. The frequency and amplitude characteristics with the effects of key variables are shown. It provides a power map as function of the stiffness and mass, which will be applied into the match design and optimization.
Research on the Singularity and Stationarity of 3-TPT Parallel Machine Tool
Authors: Zhao Heng Hua , Wang Chuan Qiang
Published: November 2011

This paper takes a new-type 3-TPT 3-DOF parallel machine tool as the object of study, established the positive and negative solution of kinematic equations of the machine, and derived the Jacobian matrix and Jacobian inverse matrix of the machine tool. On this basis, the singularity and stationarity of the machine tool were researched by using Matlab and got the expression of the absolute value of Jacobian matrix determinant of the machine tool. The velocity distribution curves of telescopic driving rods of the machine tool were simulated, too. The results show that the machine tool has advantages such as good stationarity and no singularity and so on. The study provides certain theoretical basis for the structural optimum design and performance analysis of parallel machine tool.
Experiment Study of Chip Formation and Cutting Force of Hardened AISI 1045 Steel in High Speed Machining
Authors: Li Guo He , Yan Bing , Cai Yu Jun
Published: November 2011

Orthogonal cutting experiments of hardness AISI1045 steel( HRC45) are performed. The change of chip formation and cutting force with cutting conditions are investigated through metallurgical observation, and the critical cutting speed of adiabatic shear of AISI1045 steel at different cutting depths and rake angles are given. In addition, the saw-frequency and space length of serrated chip and the influence of serrated chip on cutting force are also studied. The critical cutting speed decreases with the increase of cutting depth, but increases with the increase of rake angle. The saw-frequency of serrated chip is found to be independent of the cutting depth, and increases with the increase of cutting speed and rake angle. The cutting force decreases with the increase of cutting speed and rake angle, but increases with the increase of cutting depth, and there isn’t a sudden change of cutting force at the onset of adiabatic shear.
Analysis of Main Dimensions Effects on Performance of Transverse Flux Switched Reluctance Motors
Authors: Wang Zhi Gang , Tan Ping , Qu Sui Chun
Published: November 2011

The transverse flux switched reluctance motor (TFSRM) has the advantage of switched reluctance motors and transverse flux motor. This paper examines the effects of the main dimensions such as the polar distance, the stator core, the length of air gap ,etc, on the performance.
Characteristic Analysis of the Coupled Harmonic Model and its Application in Harmonic Power Flow
Authors: Sun Yuan Yuan , Wang Chao
Published: November 2011

This paper first gives out the harmonic coupled equivalent model for the Thyristor Controlled Reactors (TCRs) and the converter. Then, the harmonic generating characteristics of the TCRs and the converter are investigated based on the proposed model. With the help of the equivalent model, the impact of each harmonic contribution component is quantified. Moreover, based on the characteristics analysis of the model, two simplified model are proposed which are useful for simplifying the harmonic analysis of systems with TCRs and converters.
An Algorithm of Converting UG Model to MCNP Geometry Model
Authors: Zhang Jian Sheng , Zhan Xi
Published: November 2011

MCNP input file has the characteristics of complicated form and is error-prone in describing geometry model. An algorithm of converting UG model to MCNP geometry model was researched and implemented through UG OPEN API and C++ programming language. The algorithm improves the efficiency of describing MCNP geometry model, and provides a valuable reference to MCNP users.
Modeling and Design of Hydraulic Driving Hobbyhorse Clamp Holder
Authors: Li Bo , Zhu Wen Lin , Gao Hou Xiu , Zhang Qi
Published: November 2011

There are many kind of clamps used in geological exploration, and the hobbyhorse clamp obtains the widespread application because of its simple structure and reliable clasp. But theoretical analysis shows problem of the hobbyhorse clamp that clamping force is too small to overcome the resultant force of dead weight of drill pipe and tangential force from unscrewing torsional moment when drill rods in underground hole are tailed off gradually. This paper bring forward a new project on the basis of hobbyhorse clamp holder, established its static mechanics model based on the structural and mechanical analysis. Practice application has proved that the design is successful.
Fuzzy Control of Vehicle Suspension System
Authors: Yang Guo Quan , Zhao You Qun
Published: November 2011

In this paper, a semi-active suspension system has been proposed to improve the ride comfort, and a 2 DOF vehicle system is designed to simulate the actions of vehicle suspension system. The purpose of a suspension system is to support the vehicle body and increase ride comfort. The aim of the work described in the paper was to illustrate the application of fuzzy logic technique to the control of a continuously damping automotive suspension system. The ride comfort is improved by means of the reduction of the body acceleration caused by the car body when road disturbances from smooth road and real road roughness. Based on MATLAB fuzzy control toolbox, fuzzy controller is designed. Simulation analysis of suspension system is preceded by using MATLAB/Simulink7.0. The result shows that this control can improve the body acceleration, suspension distortion etc.
Research on a New Automatic Instrument Transformer Calibrator
Authors: Xu Chun Yan , Ye Li
Published: November 2011

This paper gives the structure and principle, design method, function characteristics and transformer test platform of a new automatic instrument transformer calibrator based on the conception of virtual instrument. The design project of the errors testing and the optimizing automatic voltage regulation controlling are proposed in details, introducing several applications of anti-jamming technology as well. This optimized design makes the transformer testing and measuring resolution fast, steady and accurate.
Numerical Simulation of the 1.2MW Wind Turbine Flow-Field
Authors: Li Shao Hua , Kuang Qing Feng , Yue Wei Peng , Guo Ting Ting
Published: November 2011

Based on SIMPLE algorithm, with the control equation in finite volume method and the SST K- φturbulence model, 3D models of the 1.2MW wind turbine are built to analyze the relationship between the output power and the pressure, velocity and turbulent kinetic energy of its different sections. The results show that: The change of aerodynamic performance which is caused by the interaction of blades and tower , reduces the available torque of the wind turbine that caused the decreases of the output power. The flow field region affected by central swirl and adhesive vortex is very small. The region of velocity field was affected by the wheel and wind turbine, even a few hundred meters away, but the region affected by wind turbine was smaller than by the wheel.
Design and Application of the Multifunctional Digital Automobile Instrument
Authors: Yu Chun Xuan , Zhao Wei
Published: November 2011

According to the developmental trend of modern automobile instrument, this paper puts forward a multifunctional digital instrument based on the embedded Linux system. The digital instrument panel consists of embedded microprocessor and contact screen, and it could not only receive and process all kinds of driving information from peripheral interface and display the results on the LCD, but also has the function of aided parking. This paper proposes an integrated design solution for the digital instrument. The design selects the TI’s TMS320DM355, which includes LCD and contact screen module, CAN bus module, LIN bus module, video-in and audio-out. The digital instrument can receive real-time data, and also process the data and store it in the RAM and display all vehicle operating parameters in the LCD and realizes real time monitoring in backing up. Based on the experiment, it is proved that the designed system reaches the primary design specifications.
Weak Coding Signal Detection under the Background of Sea Clutter
Authors: Liu Shi Hua , Sun Zhi Jian , Sheng Wen , Hu Zhong Ming
Published: November 2011

A new method of detection of coding signals under the background of sea clutter is presented. The process of signal detection consists of three stages: modeling sea clutter signals based on chaos, one-step ahead prediction of chaotic signals and detection decision making. In this method, models of chaotic signals were created in the form of multi-layer perceptron neural networks, coded signals take on 13-element Barker code. The experiment results show detection of coding signal by using this method has higher detection probability and lower false alarm probability and good performance of the whole detection although with a low SNR. This method turned out to be very robust to different chaotic signals.
An Optimized Angle Control Strategy for Doubly Salient Electro-Magnetic Motor Based on the Half-Bridge Converter
Authors: Li Guo Sheng , Wei Jia Dan , Chen Chang Chun , Zhou Bo , Han Chu
Published: November 2011

The doubly salient electro-magnetic motor (DSEM) suffers from significant torque ripples when operating in the conventional angle control method. To weaken the effects of the torque ripples, the ripple generation mechanism is first analyzed in this paper. Then, the operation principle and steady state of the split-capacitor in DC-link of the half-bridge converter are discussed in detail, thus an optimized control strategy of the half-bridge converter is proposed for the DSEM drives. The simulation and experimental results verify that the optimized angle control strategy can alleviate the torque ripples effectively and improve the motor performance.
Simulation and Research on Double Cylinder Hydraulic System Synchronized Control for Segment Erector of TBM
Authors: Qiu Wen Ning , Zhou Ti
Published: November 2011

This paper analyzes reasons for non-synchronization of double cylinders of segment erector of TBM and puts forward feasible synchronized control proposal. Meanwhile, mathematical modeling is built and AMEsim software is used for simulation of synchronized and coordinated control of lifting system of segment erector. The simulation results show that synchronized control accuracy meeting the design requirements.TBM (tunnel boring machine) is a large-sized hydromechatronics engineering device in modern tunnel works, and segment erector is its key component. Research on double cylinders of hydraulic system of segment erector of TBM is carried out in this paper, and AMEsim software is used to simulate the synchronized and coordinated control of lifting system of segment erector.
Real-Time Optimization of Transportation System for Earth-Rock Filled Dam Construction with GPS-Based Monitoring System
Authors: Liu Dong Hai , Jiao Kai , Sun Jing
Published: November 2011

Although large effort has been done during earth-rock filled dam construction, the artificial-based management is hard to fulfill the need of large-scale mechanized construction. With transportation monitoring system, earth move vehicles can be overall monitored. Through analytical calculation, state parameter of each controlling unit of transportation system can be obtained. On the other side, simulating model is built and calculating program is written based on the specific analysis to transportation system. When the site condition changes during construction, simulating parameters are seated and simulating calculation is done. According to the results, sensitivity analysis is done to different machinery allocation schemes. Then, combined with the site condition, best scheme can be chosen and real-time scheduling of machineries can be realized. The result is applied in the construction of Nuozhadu hydropower station project, providing scientific basis for the optimal scheduling of field machinery allocation.
Design of Coarse-Fine Combined Synchronization Control System for Lithography Based on Cross-Coupled Sliding Mode Control
Authors: Wu Zhi Pen , Chen Xing Lin
Published: November 2011

In order to achieve high position precision and synchronization between the wafer stage and the reticle stage, a cross-coupled sliding mode control scheme for a coarse-fine combined synchronization servo system of lithography is proposed. To accomplish high bandwidth and high tracking precision, a conventional linear motor is combined with a voice coil motor as a coarse-fine dual-stage control system. A cross-coupled structure is presented to decrease the synchronization error during scanning operation. Sliding mode control law is designed based on the control error and the synchronization error. Simulation results show that the synchronization error and the control error have the same order of magnitude, and the dynamic performance of the control system satisfies the design requirement.
An Improved Z-Source Boost-Buck Rectifier Topology with Lower DC Output Voltage
Authors: Shang Jian , Liu Zhi Zhen , Zhang Yan , Duan Si Hao
Published: November 2011

A Z-source boost-buck rectifier topology has been proposed to overcome the limitation of the conventional voltage source rectifier which is a boost rectifier. Conventional Z-source rectifier topology’s lowest dc output voltage is limited because increasing the shoot-through duty ratio and the modulation index simultaneously to obtain low dc output voltage is contradictory with the principle that the sum of M and D must be lower than 1. To overcome this contradiction, this paper proposes a novel topology for Z-source rectifier which can obtain lower dc output voltage with power factor correction and less input harmonic current. This paper firstly analyzes the proposed topology and makes a comparison with the conventional one. At last, the simulation results will be presented and verify its outstanding buck capability.
A Simplified Model of Write Amplification for Solid State Drives Adopting Page-Level Address Translation Mechanism
Authors: Wang Wei Neng , Wang Zong Chao , Ni Kai , Zhao Yi , Ma Jian She , Pan Long Fa
Published: November 2011

Due to its advantages, such as shock resistance, low power consumption, and so on, solid state drives are considered as a next generation storage device. And write amplification is a very import system parameter for evaluating performance. To simplify the analytical model of write amplification for solid state drives adopting page-level address translation mechanism, this paper proposes a probability model. Furthermore, numerical results based on our proposed probability model are also obtained. This paper can pose as a guideline for a first-order estimation of the write amplification for parameter ranges in solid state drives taking page mapping scheme.
Optimization Design on the Iron Beam Sectional of the Electricity Transformer
Authors: Dong Chao , Yue Xiao Wei
Published: November 2011

In order to optimize design on the iron beam sectional of the electricity transformer, a non-linear mathematical model is built to improve areas of every scale and the optimization scale is 14. Based on the principle of “equal precision designing” and GB/T 4249, the tolerance zone of the iron beam is set as the geometry tolerance of the diameter of the iron beam Ø650o+0.51+ and the inner tube Ø652+0.028with the interval of 1mm.