bluuebunny/crossref_metadata_2025 huggingface dataset:
An Automaton Fault Diagnosis Based on Shock Response Analysis
Authors: Pan Hong Xia , Pan Ming Zhi , Zhao Run Peng , Ren Hai Feng
Published: November 2012

Shock and vibration response is a particularly important signal to characterize the system state. This paper analyzes the reason of fault generated high speed machine, vibration response mechanism and its frequency characteristic. According to the measured vibration signals, done time and frequency domain features analysis, wavelet packet analysis and frequency domain energy analysis, put forward a kind of fault comprehensive diagnosis method with accurate and rapid identification characteristics, can adapt to the complex vibration response signal with interference and low signal to noise ratio.
Fault Diagnosis of Railway Axlebox Bearing Based on Wavelet Packet and Neural Network
Authors: Li Xiao Feng , Fu Yun Xiao , Jia Li Min
Published: November 2012

A real time and effective axlebox bearing fault diagnostic method is significant in the condition-based maintenance. In the axlebox bearing fault diagnostic system, fault features extraction and fault patterns classification are two important aspects to identify whether a axlebox bearing is failure or not. This paper presents a method of axlebox bearing fault diagnosis based on wavelet packet decomposition and BP neural network. First decompose the vibration signal into a finite number of coefficients by wavelet packet decomposition. Then calculate energy moment of each coefficient and take the energy moment as an eigenvector to effectively express the failure feature. Finally BP neural network is used for fault classification. The experimental results show that combining wavelet packet decomposition with BP neural network could identify the axlebox bearing fault effectively. The average diagnosis accuracy rate is 96.67%.
Analysis and Simulation of Two Hinged Ends Micro-Beam Relaxation Process
Authors: Zhu Xiao Wei , Wang Wen Fang
Published: November 2012

In order to explore micro-beam relaxation dynamics of MEMS, the beam deflection relaxation expression considering air slide-film damping effect was educed based on Euler–Bernoulli equation with boundary conditions of two hinged ends. The beam deflection relaxation process under over damping, critical damping and under damping was calculated used Maple. The relaxation simulation data of micro-beam with two hinged ends used ANSYS demonstrate that relaxation process conform to theoretical calculation and relaxation period of under damping relaxation approximate constant when damping coefficient is small, but increase significantly when damping coefficient is large.
Optimization of Refrigerator Door Structure Based on ABAQUS
Authors: Zhu Hou Yao , Zhang Chun Liang , Wang Wu Xin
Published: November 2012

The refrigerator door cover deformation or cracking is a major flaw in the BCD268 refrigerator. In this paper we create a simplified model of the refrigerator door. Based on the standard modules of ABAQUS finite element analysis software, this paper analyzed the deformation mechanism of the refrigerator door, and determined the parts of the deformation. Aiming at the deformation and cracking, the numerical simulation of BCD 268 door cover was conducted, and two kinds of different options to strengthen the ribs were proposed, then the two programs were carried out through finite element analysis, and prototypes were fabricated high and low temperature impact test for validation. Optimal structure scheme was verified by contrast. The designed lower-door covers were produced in small scale, and it proved to be consistent with the numerical results of finite element.
Analysis of CFD for Design Method of Swirl Atomizer
Authors: Yu Liang , Yuan Shu Sheng , Pang Zhi Bing , Wang Yun Liang
Published: November 2012

The UFD method was used to analyze the flow field in the swirl atomizer whose geometric structure had been designed with ideal theory algorithm. RNG (Renormalization Group) k-turbulent model was applied to the numerical simulation of the flow field, and SIMPLE algorithm was used to solve the finite difference equations. Through the analysis of pressure and velocity fields get by the numerical simulation, we found that the use of CFD method in the swirl atomizer design is beneficial for getting more detailed and accurate flow structure and advantageous to analyze the influence of different nozzle geometry, and then given a reasonable design opinion.
Rotary Kiln Drive System of Kinematics Modeling Analysis Based on ADAMS
Authors: Jiang Zhi Hong , Cai Gai Ping
Published: November 2012

Large-scale rotary kiln drive system model is created based on virtual prototyping technology and ADAMS. After analysis of the actual working conditions, system constraints are added to the rotary kiln model, and kinematic analysis to be process. At last, kinematics curve consistent with the theoretical analysis on the model of the rotary kiln drive system, which verifies the built rotary kiln drive is correct. This kinetic analysis is ready for the follow dynamic analysis.
Numerical Simulation of Natural Cavitating Flow over Axisymmetric Bodies
Authors: Liu Qian Kun , Gao Ye
Published: November 2012

The hydrodynamic characteristics of bodies are greatly affected by cavitation. Coupling with natural cavitaion model, a multiphase CFD method is developed and is employed to simulate supercavitating and partial cavitating flows over axisymmetric bodies using FLUENT 6.2. The results of supercavitation of a disk cavitator agree well with the boundary element method (BEM), the analytical relations and available experimental results. The present computations and the BEM results are compared with experiments for partial cavitating flows over three typical axisymmetric bodies and the results are discussed. Limitations are on the pressure prediction in the cavity closure region for the BEM, although fairly good quantitative agreement is obtained for three axisymmetric bodies at most of cavitation region. The present computational model on cavitating flows are validated, offering references and bases for hydrodynamic researches.
Prediction of Nonlinear Contact Force of Piston Skirt and Cylinder Liner under the Function of Clap Force
Authors: Jin Zhou , Yu Zhi  Zhuang , Yang Lin Sheng
Published: November 2012

The piston skirt and cylinder liner is a coupled contact model, It is of great importance to analyze the contact stress and deformation. Due to the existence of the gap and the lateral clap force between piston skirt and cylinder liner, which leads to the lateral movement. According to the secondary movement and hydrodynamic lubrication theory, the maximum lateral clap force can be obtained in a working condition, before piston crosses TDC, the huge gas pressure makes the piston skirt and cylinder liner collision contact, and creates the enormous clap force, which can aggravate the noise and vibration between piston skirt and cylinder liner. We would set maximum lateral clap force as a dangerous condition, which can be loaded on the contact model. By the means of nonlinear software ABAQUS, to establish the piston skirt and cylinder liner contact model, and analyze the contact stress and deformation.
Reduced-Order Model for Unsteady Compressible Flow Based on POD-Galerkin Projection
Authors: Dou Yi Bin , Xu Min
Published: November 2012

Italic textIn this paper, the reduced-order model (ROM) of unsteady compressible flow based on POD-Galerkin projection has been investigated. The Euler equation formulated with the conservative variables for compressible flow has been reformulated using modified primitive variables. The POD modes are computed using snapshot method and then an explicit quadratic ROM is constructed by applying the Galerkin projection to the modified Euler equation. Because of lacking any dissipation in POD-Galerkin projection, the flow calibration method is introduced to account for the numerical dissipation to stabilize the ROM. At last, the NACA0012 airfoil undergoing pitch harmonic oscillating in Mach number Mach = 0.755 is calculated as a test case. For this flow configuration, the calibrated coefficients of the ROM are almost the same as the initial guess which comes from POD-Galerkin projection; the differences are mostly focused on the linear Lijcoefficients and quadratic Qijkcoefficients.
Fast Terminal Fuzzy Sliding Mode Control for a Three-Links Spatial Robot
Authors: Hu Sheng Bin , Lu Wen Hua , Cao Da Min , Xu Hai Rong
Published: November 2012

To achieve high performance tracing control of the three-links spatial robot, a fast terminal fuzzy sliding mode control method is proposed in this paper. Firstly, the control method can efficiently solve the singularity of the controller through switching between terminal sliding mode surface and linear sliding mode surface. Secondly, to diminish the chattering in the control input, a fuzzy controller is designed to adjust the generalized gain of fast terminal fuzzy sliding mode controller according to fast terminal sliding mode surface. The stability of the control algorithm is verified by using Lyapunov theory. The proposed controller is then applied to the control of a three-links spatial robot. Simulation results show the validity of the proposed control scheme.
Dynamic Property Analysis of Rubber Absorber in Rail Fastenings of Different Force Condition
Authors: Wang Shu Wei , Luo Yan Yun , Li Li , Liu Yan
Published: November 2012

This paper studies the dynamic property of rubber absorber in rail fastening by electro-hydraulic testing machine. Two different types of rail fastening are tested. In one fastening the rubber component is in compressed condition (RCRF). While in another the rubber is in sheared (RSRF). A nonlinear dynamic model of rubber absorber in rail fastening is proposed. The model parameters are obtained by the least square method. The accuracy of the obtained model is verified by measured result. The two results are in good agreement. The dynamic stiffness and damping are analyzed, and the results show that dynamic stiffness and damping are closely related to the frequency and amplitude of excitation. Nonlinear characteristic becomes greater with increasing excitation amplitude for the both rail fastenings. For different excitation frequency, the vibration reduction effect of RSRF is more stable than that of RCRF.
Rehabilitation of Strength of Steel Plate with a Corroding Hole Bonded by Composite Patches
Authors: Zhang Xiang Ming , Chen Li Wei , You Ze Long , Hu Ming Yong , Yang Shao Hong
Published: November 2012

The failure mode of steel plate with a center elliptic corroding hole double-sided adhesively bonded by carbon fiber composite patch is identified and studied, and analytical solution to load-carrying capacity of damaged steel plate bonded by composite patch is presented in this paper. Ultimate load of patched steel plate corresponding to each failure mode is derived and calculated respectively, the load carrying capacity of the patched plate is equal to the minimum value of these calculations. Yielding load when yielding occurs near the hole-edge of repaired structure from present method was compared to the results of ANSYS FEA, and the ultimate load of repaired plate from present method was compared to the test results. Results indicate: Repaired by bonded composite patch, static strength and loading carrying capacity of damaged steel plate or structures can be effectively restored. Yielding load and ultimate load of patched steel plate is visibly increased. The present analytical results have a good agreement with FEA and experimental results.
Design Guidelines on the Ultimate Strength of Retrofitted Deep Concrete Coupling Beams by Laterally Restrained Side Plates
Authors: Cheng Bei , Su Ray K.L. , Luo Jian
Published: November 2012

Existing deep reinforced concrete (RC) coupling beams with low shear span ratios and conventionally reinforced shear stirrups tend to fail in a brittle manner with limited ductility and deformability under reversed cyclic loading. Experimental and numerical studies have demonstrated the effectiveness of laterally restrained steel plate (LRSP) retrofitting method in improving the seismic performance of deep RC coupling beams. In this way, the deformability and energy dissipation of the retrofitted beams are greatly enhanced. Based on the experimental studies and numerical simulation of LRSP coupling beams, an original design procedure on the ultimate strength of LRSP coupling beams is proposed. The proposed design guidelines consist of seven parts, which are (1) estimation of shear capacity of RC component, (2) estimation of plate size, (3) design of bolt group, (4) estimation of axial force, (5) determination of buckling effect coefficient, (6) shear resistance design of the retrofitted beam, and (7) flexural resistance design of the retrofitted beam.
Blasting Demolition Technology and Vibration Testing of 210m Reinforced Concrete Chimney
Authors: Xu Shun Xiang , Chen De Zhi
Published: November 2012

This paper describes the successful experience of the directional control blasting of 210m-high reinforced concrete chimney of Nanchang Power Plant in Jiangxi Province called as “First height in Asia”. It emphatically describes the pretreatment measures, blasting cut shape and size, blasting parameters, electronic digital detonator detonating network and blasting safety technology. And the blasting vibration was tested and analyzed, and this paper presents the method for opening the arch overlarge oriented window and comprehensive protection method for anti-flyrock splash, vibration reduction and dustfall. Especially, the electronic digital detonator was first applied in the blasting demolition of 210m-high structures, it improves the delay precision and also has a good anti-stray current effect to ensure that the blasting can be safely implemented in the power plant, and it has a good application prospect in the future large-scale and high level complex engineering blasting.
Reactive Power Compensation of Distribution Network Based on Immune and Particle Swarm Optimization Algorithm
Authors: Cui Wei , Li Lin Chuan , Zhang Lei , Sun Qian
Published: November 2012

The reactive power compensation optimization in distribution network has the important meaning in maintaining system voltage stability, decreasing network loss and reducing operation costs. In order to meet factual conditions, we assume the system operates in minimum, normal and maximum three load modes and the objective function of problem includes the costs of power loss and the dynamic reactive power compensation devices allocated. In this paper we use Artificial Immune Algorithm(AIA) and Particle Swarm Optimization Algorithm(PSO) to determine compensate nodes and use the back/forward sweep algorithm calculate load flows. After applied into 28-nodes system, the result demonstrates the method is feasible and effective.
Performance Study of Brushless Doubly-Fed Machines in Variable Speed Constant Frequency Wind Power Generation
Authors: Zhang Yue , Wang Feng Xiang
Published: November 2012

The brushless doubly-fed machine (BDFM) is a new type of induction machine with good application in wind power generation. In this paper, the design method for the stator winding and rotor winding of BDFM in detail on the basis of operation principle of the machine is introduced. As an example, The performance simulation for a 480kW cage rotor BDFM with 8-pole stator power winding and 4-pole control winding can be considered under the condition of no-load, rated load and variable speed constant frequency operation based on field-circuit coupled finite element analysis. Simulation results show that the design method has good performance and is feasible in variable speed constant frequency wind generation systems.
Comparisons of the Power-Feedback MPPT Algorithms for the Photovoltaic Systems
Authors: Yu Ting Chung , Lin Yih Bin , Lin Yu Cheng
Published: November 2012

The purpose of this paper is to compare three power-feedback maximum power point tracking (MPPT) algorithms used in photovoltaic systems. The Matlab/Simulink is used in this paper to establish a model of photovoltaic system with MPPT function. This system is developed by combining the models of established PV module and DC-DC boost converter with the power-feedback MPPT algorithms of perturbation and observation, incremental conductance and hill climbing, respectively. The system will be simulated under different weather conditions and MPPT algorithms. According to the comparisons of the simulation results, it can be observed that the photovoltaic simulation system can track the maximum power accurately using the three MPPT algorithms discussed in this paper. HC algorithm possesses fast dynamic response, but P&O algorithm is well regulated PV output voltage and power than HC algorithm. The tracking time spent by INC algorithm is a little longer than the other two algorithms. The HC algorithm is suitable for the cases of battery charging which doesn't need extremely stable voltage, and the P&O algorithm is more suitable for the system with precision electric instruments. Furthermore, the INC algorithm is adaptable to the cases of fast changing weather conditions owing to its advantage of no misjudgment.
Investigation of Impact Test of Power Battery under Different Environment Temperatures
Authors: Wang Hong Wei , Liu Jun , Xiao Hai Qing , Wang Chao
Published: November 2012

The impact tests are generally performed at room temperature in actual standards, but in fact, the power battery work in variety of different environment temperatures. Therefore, the impact tests of the power battery were researched at different environment temperatures (-30°C, 20°C, 40°C and 65°C). The results showed that the impact can induce the internal short circuit, at the same time, if battery system is kept running at high environment temperature, the exothermic effect will induce the heat accumulation inside the battery, leading to thermal runaway and even the battery burning and explosion. The other result is that the higher the environment temperature is, the worse the battery thermal stability is. Temperature rise rate and maximum temperature was a linear relationship of the samples that did not burn during impact tests. And the temperature rise rate and maximum temperature was the cubic polynomial relationship of the samples that burn during impact tests. That is to say, the battery is prone to induce thermal runaway when the temperature rise rate is high.
Micro-Deposition of the Film Material Using Femtosecond Laser Pulse
Authors: Li Yang , Sun Ping Ping , Wu Ai Qing
Published: November 2012

The femtosecond laser-induced forward transfer of the aluminum film had been studied experimentally by single-shot laser pulse (pulse duration 148fs, central wavelength 775nm). With the help of the atomic force microscope and scanning electron microscope, the dependence of morphology and dimension of deposited dots on irradiated laser pulse energy were investigated. It was revealed the threshold fluence for transfer was ~6.3 J/cm2 for the aluminum thin film with a thickness of ~500 nm. It also was presented the micro patterns of the aluminum film on a quartz substrate fabricated using the femtosecond laser-induced forward transfer .
Application of Image Processing in Plasma Jet Morphological Analysis
Authors: Tian Xiao Jing , Dong Hua Jun , Yin Da Peng , Zhao Zi Yu
Published: November 2012

The morphology of plasma jet (PJ) directly demonstrates whether the procedure of spray processes is stable. The paper proposes an acquisition system of PJ images and an improved edge detection method is presented to get the morphology of PJ. Firstly, the PJ images are gray enhanced to remove the influence of noises. Then they are enhanced with edge sharpening. At last, they are edge detected through Canny, Laplacian and Sobel operator. From the results we can see that the improved method can get more clear and more complete PJ image morphology than traditional one. The processing methods provide foundation for the online detection of PJ morphology and for diagnosing the forming quality.
Implementation of Fixed Sampling Period M/T Method Based on VHDL
Authors: Xia Si Tai , Li Xiu Juan
Published: November 2012

Take insufficiency of classical velocity measurement methods into consideration, this paper introduces a method which has a good test accuracy in a wide range, fixed sampling period M/T method, to determine velocity and position information of the encoder. Firstly, its measurement principle is analyzed in detail through logic and timing relationship. Then realization of every module is achieved with VHDL. Finally, ModelSim is used to simulation and test to verify the correctness of the method. In the future, it can be widely used in practical applications.
Design of Interior Off-Line Temperature Detector for the Ultrahigh Pressure Vessel
Authors: Xin Jun , Yang Wen Tong , Zhao Bo Yang , An Guo Ping
Published: November 2012

The gas temperature in vessel will be significantly increased according to the aeration speed and pressure during the aeration or deflation for the ultrahigh pressure vessel. Due to the restriction of air tightness and structure for the ultrahigh pressure vessel, it is difficult to measure the gas temperature by adopting the traditional measurement method without change of the vessel structure. In this paper, a new type interior off-line temperature detector is designed to measure the gas temperature in vessel. The power, temperature sensors, processor, memory and human-computer communication module is linear arranged in the circuit board, which ensure that the temperature detector can be putted inside the ultrahigh pressure vessel through the vessel inlet of diameter Ø25mm. The experiment results show that the gas temperature in vessel can be effectively measured by adopting the interior off-line temperature detector without change of the vessel structure.
A Self-Integrating Rogowski Coil for Lightning Current Sensor
Authors: Wu Xu Tao , Ding Pei , Guo Fei , Liang Jian Feng , Li Jun Hao , Li Yan Ming
Published: November 2012

Lightning current is very important parameter for evaluating the overvoltage of the power system and characterizing the electromagnetic compatibility of the electronic equipments. Therefore, it is indispensable to measure lighting current by a suitable sensor. This paper presents a self-integrating rogowski coil for lightning current sensor, and introduces the operating principle and analyses characteristics of it. In addition, to improve the precision of the sensor this paper proposes design procedure of the phase compensation method and the circuit structure to implement the phase compensation method. The simulation results verify that the phase compensation method can enhance the precision of the self-integrating rogowski coil.
Decoupled Adaptive Tracking Algorithm for Multi-Sensor Measurement Fusion
Authors: Fong Li Wei
Published: November 2012

A decoupled adaptive tracking filter is developed for centralized measurement fusion to track the same maneuvering target to improve the tracking accuracy. The proposed approach consists of a dual-band Kalman filter and a two-category Bayesian classifier. Based upon data compression and decoupling techniques, two parallel decoupled filters are obtained for lessening computation. The Bayesian classification scheme is employed which involves switching between high-level-band filter and low-level-band filter to continuously resist different target maneuver turns. The simulation results are presented which demonstrate the effectiveness of the proposed method.
Development of Multivariate Measurement and Control System of Threshing Cylinder in Combine Harvester
Authors: Wang Xin , Wang Shu Mao , Miedzinski B.
Published: November 2012

Threshing cylinder is a core component of combine harvester which determines the working performance of the entire machine and also consumes a majority of the whole combine harvester’s power. In this paper, a multivariate measurement and control system was established. The control algorithms were developed by linear regression theory and abundant experimental data. The Field trials were conducted in several major grain producing areas in China for data acquisition. Practical application indicated that the developed multivariate measurement and control system could meet the demand of optimal operation of threshing cylinder. The working performance and efficiency of combine harvester was improved.
Flexible Packaging Liquid Milk Quality Testing Instrument Based on Virtual Instrument
Authors: Wang Ying , Shi Rong , Lu Wen Juan
Published: November 2012

Base on the concept of virtual instrument, an inspection system for quality of flexible packaging UHT liquid milk was developed, which do not open the package of UHT. The system has functions building a product prescription, quality inspection, forming a experiment report. A Personalized instrument can de designed according to user requirements. Experimental results show that compared with conventional method the non-destructive detector has a highly precision .The results are consistent with the test of titratable acidity, which provide new avenues for non-destructive quality inspection of soft drinks.
An Infrared Thermal Image Processing Framework for Defect Detection of a Metal Part with Rough Surface
Authors: Xie Jing , Xu Chang Hang , Chen Guo Ming
Published: November 2012

We propose an infrared thermal image processing framework based on a modified fuzzy c-means clustering algorithm with revised similarity measure in this paper. The framework can realize the defect detection of a metal part with rough surface. Firstly, a comprehensive method is used to preprocess infrared thermal image. Secondly, the preprocessed image is segmented using modified fuzzy c-means clustering algorithm with revised similarity measure. Finally, taking the average gray level of each cluster in the original gray scale image as a feature, defect cluster is recognized. Experimental result shows that the proposed framework has very promising performance and can obtain precise information of defects on a metal part with rough surface.
Study on Precision Scanning Measurement Based on Acousto-Optic Deflection Technology
Authors: Ding Xiao Hua , Ren Yong Jie , Yang Xue You
Published: November 2012

Scanning measurement is a basic means to achieve high precision geometric measurement. However, the scanning device has a congenital defect which is the presence of a mechanical scanning device, thus, it has some issues such as wear, vibration, temperature sensitive.This articlecreatively put forward a kind of control method which is using acousto-optic deflection technology to realize the laser scanningfrom the general character of scanning measurement.The method has the advantages of the principle, it eliminatestheinherent defect of rotary machine structure on the measurement accuracy, speed, controllability, and stability. The exploration and research of this method will provides a new non inertial rotation scanning means for optical scanning measurement. More important, the implementation of the method will provides a new thought and method for the kind of problem about beam scanning measurement of geometric measurement.
Performance Analysis of Ground Moving Target Detection for Airborne MIMO Radar
Authors: Li Cong Cong , Li Jun , Li Chao Hai , Huang Wen Jun
Published: November 2012

The performance of a Ground Moving Target Indication (GMTI) radar is determined by the interference level of the clutter to a large extent. With the longer illumination and the larger aperture, Multiple-Input, Multiple-Output (MIMO) radar greatly enhances the ability to detect the slow-moving target. This paper compares MIMO radar with conventional phased-array radar in terms of signal to clutter and noise ratio (SCNR) performance. Moreover, the paper proves the fact that the improvement of SCNR with MIMO techniques is not only limited in the antenna configuration of the side-looking but also non-sidelooking array-antenna. The analysis of mianlobe clutter and sidelobe clutter levels can greatly simplify the computation of the total clutter. Finally, the experimental simulation is been given.
The Embedded Design of Vibrator Sweep Signal Generator Based on ARM9
Authors: Shen Yuan Yuan , Zheng Gong Ming
Published: November 2012

This paper presents the embedded design of sweep signal generator which is based on ARM9+Linux platform. It describes DAC712 device dentally and prepared a DAC driver and upper application. Finally, the test signals generated by the system obtained the test results and the results were analyzed.
Design of Data Transfer System Based on PCI Express Interface Applied in High-Speed Railway
Authors: Zhou Xiao Bo , Xia Min , Cheng Hai Long
Published: November 2012

To improve data transmission performance of the data acquisition card, a design of high-speed data transmission system is proposed in the thesis. Using FPGA of programmable logic devices, adopting Verilog HDL of hardware description language, the design of modularization and DMA transmission method is implemented in FPGA. Eventually the design implements the data transmission with high-speed through PCI Express interface. Through simulation and verification based on hardware system, this design is proved to be feasible and can satisfy the performance requirements of data transmission in the high-speed data acquisition card applied in high-speed railway communication. The design also has some value of application and reference for a universal data acquisition card.
A High Accuracy Direction-Finding Method of 2-D Multi-Beams
Authors: Wang Zhi Gang , Wang Fang
Published: November 2012

In order to acquire a kind of high accuracy multi-beams direction-finding method, this paper proposes a sort of 2-D multi-beams direction-finding method based on surface fitting. Three main factors influencing direction-finding accuracy are summarized in this paper, and the specific influence of these three factors to direction finding accuracy are analyzed by simulation experiments. The result of simulation experiments analysis shows that this method has higher steadiness and better direction-finding accuracy.
The Research of Video Signal Capture and Processing Technology in Microteching System
Authors: Ye Xi En , Zhu Yin Feng
Published: November 2012

This paper describes a video signal processing system, based on the research of DirectShow streaming media processing platform, H.264/AVC video coding technology and multi-channel video encoding chip SC8919 which includes H.264 hardware video encoder. This system can compress four channel D1(720*576) size of the image data collected by camera at the rate of 30fps into standard H.264 stream, and upload it to the control room to store and decode broadcast through existed campus Ethernet without additional laying line.
The Prediction of Indoor Radio Waves Propagation Characteristics Based on FDTD Algorithm
Authors: Ma Li , Zou Peng , Zhou Xiao Ping
Published: November 2012

The prediction of the indoor radio waves propagation characteristic can be a difficult task because of the indoor environment complexity. Based on the finite difference time domain algorithm, when the monopole antenna is used as the excitation, the indoor radio waves propagation characteristic is researched by using measurment method and simulation method. The effectivity of prediction method is verified by comparing the prediction results with the measurment results. The quantitative research of this paper has certain guiding significance to the confirmation of the wireless digital communication reasonable coverage.
Design and Experimental Research on a Miniaturized Archimedean Spiral Antenna
Authors: Jiang Ming , Song Li Zhong
Published: November 2012

The Archimedean spiral (ARSP) antenna is widely used in many wide band electronic systems due to its good radiation performances. This paper designed and fabricated a specific planar ARSP antenna within the operating frequency range of 1 GHz to 9GHz. The meander line technique was employed to miniaturize the planar ARSP antenna. The designed ARSP antenna was fed by a wide band miniaturized bent microstrip Balun. The diameter of the fabricated ARSP antenna was 82 millimeters. A metal cavity filled with absorber materials was used to obtain the unidirectional radiation patterns and its height was 30 millimeters. The parameters of designed ARSP antenna were determined by numerical simulations. A practical designed ARSP antenna was fabricated according to designed parameters and the experimental results of the fabricated ARSP antenna are provided. The experimental research results demonstrate that the fabricated ARSP antenna has radiation performances of wide beam and approximately circular polarization. The fabricated ARSP antenna can be used in several practical electronic systems such as wide band radar systems.
Coupled Simulation Study on the Working Device of the Excavator Based on VL Motion
Authors: Jin Shao Xun , Chen Hui Peng , Chen Guo Jin
Published: November 2012

On the foundation of analyzing the excavator’s working device structure, this paper built its three-dimensional model in Catia embedded in the VL Motion, created the bodies, defined the joints and corresponding drive interface to produce the multi-body dynamic model. According to the analysis on the hydraulic system of the working device, it built the electro-hydraulic system with the interface of Motion in AMEsim and then performed the coupled simulation between the Motion and AMEsim. Aiming at the working device’s performance defects, such as the worse displacement tracking, the slow respond, it designed the PID closed loop control system to improve the system’s performance. The simulation results show that the working device’s combination performance has been improved greatly, respond speed becomes fast and the ability of displacement tracking is better.
The Scattering of Carbon Nanotubes on the Gaussian Beam
Authors: Xing Shi Tong , Yang Hui , Zheng Gang , Yang Hai Ma
Published: November 2012

The first-order approximation description of Gaussian beam in the two parallel Cartesian coordinates was introduced. On the basis of Generalized Mie theory, adopting the relation between the spherical vector wave functions belonging to a rotating Cartesian coordinate system, the electromagnetic fields of Gaussian beam with spherical vector wave functions was deduced at any right coordinates system. Then taking advantage of the cylindrical vector wave functions given by Stratton, the relationship of the spherical vector wave functions expressed in cylindrical vector wave functions was deduced. Finally the electromagnetic fields of infinitely long cylinder was expanded by the cylindrical vector, and the approximate expression of the cylinder to the far zone scattered field was solved.
Research on the Protection of Out-of-Position Child Occupants Based on the MADYMO Model
Authors: Yu Hong Tao , Cao Jian Xiao , Zhao Gui Fan , Wei Qing Fu
Published: November 2012

The model of the airbag deployment test has been established based on U.S. FMVSS 208 regulations, and the effect of the protection of PAB’s two folding patterns on out-of-position child occupants has been tested. The Experiments show that the "Z" shaped folding is better than the winding folding according to the experiment model. In addition, optimize the airbag by the method of expanding the size of pores and the horizontal size of the airbag to achieve better protection for out-of-position child occupants.
The Research and Analysis of Lexical Analyzer in Prolog Compiler
Authors: Li Dan Cheng , Cai Xiao Cen , Han Chun Yan , Liu Yi Xian
Published: November 2012

This paper analyzes structural features of the prolog compiler on the basis of its executive mechanism. The main focus of the research targets the functional characteristics and the working mechanism of the compiler through the analysis of prolog language organizing and translating procedure in conjunction with the logic-reasoning attribute of the language. The paper illustrates structure of three important modules and demonstrates their corresponding realization method. The research of lexical compiler will lay a foundation for future works of upgrading and developing Prolog compiler.
Design and Simulation of the Novel Parallel Resonant Inverter
Authors: Yang Ying Hua , Gao Hong Lin , Wang Xin Hua , Tang Jin Fei , Huang Bo
Published: November 2012

To overcome the problems of traditional PWM inverter, the paper puts forward a novel parallel resonant inverter, and expounds the inverter’s configuration and working principle. It analyses choice tenet of resonant inductance and resonant capacitance of resonant link. It confirms the parameters through calculation accordimg to the need of system. It simulates the resonant link of different parameters, comparison of the simulation results testifys validity of the resonant inverter.
The Simulation of Semi-Active Suspension System Based on RBF Neural Network Sliding Mode Control
Authors: Zhu Hua
Published: November 2012

Focusing on the nonlinear and uncertain characteristics of suspension system,a 2-DOF vehicle is regarded as the control object, sliding mode theory was used to design a sliding mode controller for the 2 DOFs vehicle semi-active suspension system,then RBF neural network was employed to optimize the sliding mode controller.The control effects of three key performance parameters of suspension, the acceleration of car body, the dynamic travel of suspension and the dynamic deflection of tire are studied under random excitation conditions.The results indicate that in comparison with the passive suspension，sliding mode semi-active control based on RBF neural network can improve suspension performance effectively.
The Simulation and Experimental Research on Reverberation Time in Car Speaker Sound Field
Authors: Wang Zhi Jian , Fan Chao Gang
Published: November 2012

As an important element of the index in room acoustics, the reverberation time has been considered as an objective parameter with clear concept and had good correlation with the subjective perceptions in the field of psycho-acoustic criteria. Through the computer acoustic simulation software EASE and the electro-acoustic test system CLIO, this paper conducts research on the reverberation time of the car speaker sound field, which in the domestic car of a certain type, studies show that EASE is accurate and reliable in the simulation of the car speaker sound field, the reverberation time is greater than 0.4s when the frequency less than 500 HZ and less than 0.1s when the frequency greater than 1000 HZ, when reaches to 500 HZ, the reverberation time reaches the maximum 1.103s.
The Research of Optimal Image Mosaic Method Based on Wavelet Transform
Authors: Bu Xian Xian , Li Hong Xia , Deng Li Miao
Published: November 2012

Image mosaic (Mosaic) for a given image sequence is the first image sequence alignment positioning, and then fusion spliced to produce a seamless, high-resolution large-scale scene images. This paper discusses the calculation model in the wavelet transform in image processing and wavelet transform image stitching. This paper presents the optimal image mosaic method based on Wavelet transform and introduces a seamless optimization algorithm based on wavelet transform and its validity through a concrete example simulation.
ABS Simulation System of Automobile Based on Virtual Technology
Authors: Yin Zhan Shun , Wang Yi Jun
Published: November 2012

The difficulty of car ABS system on the teaching analysis, design, automotive brake simulation control system based on virtual technology through Labview software and data acquisition card with the host PC, as well as control the drive circuit and the sensor circuitdesign, car braking process simulation, the composition of the ABS system, the structural and mechanical connection between the real show, but also by the ABS system failure code corresponding to the fault simulation settings for simulation training in diagnosis and exclude vehicle use and maintenance of the common failures of the ABS system. The results showed that: automotive brake hardware circuit design, simulation control system is reasonably practicable, the control strategy used by the software is correct and effective, stable and reliable system operation, automotive brake simulation system design teaching.
Design and Simulation of a Type of Four Degrees of Freedom Parallel Robot
Authors: Xu Zhen Da , You Da Zhang
Published: November 2012

A type of four degrees of freedom parallel robot is designed, which can make the workbench achieve the translational motion of three directions and one rotational motion. The constituent part of the robot is given. And we analyze the design principle and process of its work space. Though the CATIA simulation software, the whole movement of the robot is dynamically presented, showing the features of the various body parts and verifying the feasibility of its practical movement.
Technology Mapping for Heterogeneous FPGA in Different EDA Stages
Authors: Fan Quan Run , Pan Feng
Published: November 2012

In traditional EDA flow, Technology mapping is performed after logic synthesis. Besides programmable logic blocks, heterogeneous FPGAs also have some hard blocks, such as memory block and multiplier, built in it. After logic synthesis, it will be difficult for technology mapping to find sub-circuits that can be implemented in hard blocks. In this paper, a systematic technology mapping approach is proposed. In the design phase, with the support of CAD tools, a module based design approach is used to map some design block to large hard blocks. During register transfer level synthesis, some functions that are suitable to be implemented in small hard blocks are identified. Other logic functions are mapped into lookup tables with different input size.
A Novel Image Watermarking Scheme Based on MCA Neural Networks
Authors: Li Yan Mei , Luo Jian
Published: November 2012

Minor component analysis (MCA) plays an important role in signal processing and data analysis. In this paper, we propose a novel watermarking scheme using MCA neural networks. The proposed scheme can detect and localize any modification made to the image, which can be used for integrity verification and authentication. Another important property of this proposed scheme is that any gray scale watermark can be easily inserted into the image compared to some other watermarking method such as LSB (least significant bit) method. Furthermore, the proposed scheme can insert any watermark into one image without making any visible changes to the image. Since the minor component of each image is different, and it requires a user key during both the insertion and extraction procedures, it is not possible for an infringer to insert a new watermark or alter the existing one that could pass the test. Finally, various experiments also confirm such properties of the proposed scheme.
Network Formation in Various Dispersing Medium of Hydrophobic Colloidal Silicon Dioxide
Authors: Toprasri Photchanart , Phaechamud Thawatchai
Published: November 2012

Colloidal silicon dioxide is a fine amorphous powder consisting of particles about 7-40 nm in size. This study utilized hydrophobic colloidal silicon dioxide, aerosil R 972, as gelling agent in non-aqueous systems. Aerosil R 972 could convert light mineral oil and Luvitol EHO® into gel at concentrations of 7 and 10% by weight, respectively. The appearance of the systems prepared from polyethylene glycol 400, 600 and light mineral oil was clear, but the others were turbid. There was no phase separation or color changes of the systems after temperature change of 6 cycles. The obtained gel exhibited very little change of pH and viscosity after stability testing. After aerosil R 972 was incorporated into the mixed media with different dielectric constant, all systems showed the decrease of a viscosity, especially, the formulations having low dielectric constant. The addition of aerosil R 972 into dispersing medium with higher dielectric constant provided higher viscosity of the system because of the mismatch of the polarity between particles and dispersing media. In case of the incorporation of aerosil R 972 into mixed media, the rank order of viscosity was PEG 400–glycerin> PEG 400–PG > PEG 400–water. All of PEG 400–glycerin mixtures were obviously converted into gel, while only PEG was not converted with aerosil R 972 addition.
Configurable Software Development Environment Design for Measurement and Control System Based on Virtual Instruments
Authors: Wang Ling , Fu Han , Wang Shu Mao
Published: November 2012

Software development for a measurement and control system is a time consuming performance. To accelerate development process, a graphic software development environment was designed and established based on the principle of Virtual Instruments. In the developed environment, three layers including interface editing, channel configuration and database were designed for software incubation with codeless operation. The users could newly establish or re-edit a project according to designed software development flow and database would automatically generate for interface and channel management. An application for couple-tank water level control system was constructed in the developed environment to validate the system reliability and usability. Obtained results showed that software could be established in the development environment for measurement and control system with simplified operation.
Synthetic Glass Nanopore for Single Molecule Detection
Authors: Sun Xiu Hua , Gao Chang Lu , Gu Li Qun
Published: November 2012

The molecular-scale pore structure, called nanopore, interacting with target molecules in its functionalized lumen, can produce characteristic changes in the pore conductance, which allows us to identify single molecules and simultaneously quantify each target species in the mixture. Nanopore sensors have been created for tremendous biomedical detections, with targets ranging from metal ions, drug compounds and cellular second messengers, to proteins and DNAs. Here we will review our recent discoveries with a lab-in-hand glass nanopore: single-molecule discrimination of chiral enantiomers with a trapped cyclodextrin, sensing of bioterrorist agent ricin and site-directed capturing a single nanoparticle.
Different Variances Used for Analyzing the Noise Type of Atomic Clock
Authors: Zhai Jing , Dong Lian , Zhang Shu Sheng , Lu Fu Min , Hu Li Zhi
Published: November 2012

Stability is an important factor to measure the quality of an atomic clock. The random factor that affects atomic clock includes five kinds of noise. The random noise can be expressed by spectral density function. In a certain smooth time, only one or two types of noise can influence the atomic clock’s stability. Through the relationship between spectral density function and atomic clock stability analysis variance, such as Allan variance, it’s possible to distinguish the kind of noise on different smooth time. When lacking of data, there is a way that can increase the amount of data by mapping extensions, and it can also improve the degree of confidence in the larger smooth time.
Simulation Analysis of Three-Phase Inverter DC Link Current
Authors: Chen Guo Qiang , Huang Jun Jie
Published: November 2012

The DC link current spectrum has important effects on the active state and life of the battery cell and the bus capacitance in the three-phase inverter. Based on the load of PMSM (Permanent Magnet Synchronous Motor), the DC link current characteristics are presented intuitively using the computer simulation. The paper discusses the method and procedure to the simulation model that includes several key modules: PWM module, inverter module, and PMSM module. The simulating results are presented and analyzed.
DOA Estimation Based on the Multipath of the MIMO Radar Target
Authors: Ji Ai Guo , Wang Tao , Zhu Zhi Gang
Published: November 2012

The DOA Estimation of the MIMO radar is widely used to determine the position of the objects. Having been considered the multipath communication environment, this paper estimates the DOA information of low elevation targets using beam space MUSIC algorithm based on the model of uniform linear array of MIMO radar. Simulations have shown that the algorithm is effective in the multipath spread environment, and the resolution of the DOA estimation of angular is about 0.5°