bluuebunny/crossref_metadata_2025 huggingface dataset:
A Novel Technique for PAR Reduction in DRM
Authors: Xu Wei Zhang , Yang Zhan Xin , Yu Xin Le
Published: July 2012

PAR (Peak-to-Average Power Ratio) is one of significant issues in a DRM transmitter. To reduce the PAR of DRM signals, an iterative pre-distortion technique is proposed in this paper. This technique improves the RMS (Root Mean Square) power of transmitter while the effect on DRM signal quality is negligible. Research has been done on the impact that the processing parameters caused to DRM signal quality. Simulation and test indicate that in the case that the quality requirements for the RF signal in the DRM specification is satisfied, DRM output power is increased to 9kw from 5kw (RMS power) based on a 10kw (carrier power) DX transmitter, thereby improving the capability of the transmitter greatly.
Cellular Automata-Based WSN Energy Saving Technology
Authors: Li Wei Qiao , Yu Qin , Ma Li Xiang
Published: July 2012

Wireless sensor network is a new type of wireless network. IEEE 802.15.4 / Zigbee standards with low energy consumption, low speed characteristics has been widely used in wireless sensor network. As the wireless sensor nodes are often set in complex geographical environment and had not continuous power supply, thus saving energy has been one of the main directions of research at home and abroad. Cellular automata are a mimic biological cell reproduction form of dynamical system, with a simple rule to reveal the complex global characteristics. This paper presents a kind of cellular automata and Zigbee based wireless sensor network binding mechanism, so that the wireless node according to the communication state during hibernation and job switching between states in order to achieve the purpose of energy saving. Simulations show that the mechanism can reduce the network energy consumption, improve energy utilization rate, and prolong the survival time of the node.
Remote Intelligent Fault Diagnosis System Modeling Based on Multi-Agent
Authors: Zhang Ji Jun , Ma Deng Wu , Fan Geng , Deng Li
Published: July 2012

With the development of intelligent fault diagnosis technology, research on the application of multi-Agent theory in the remote fault diagnosis system is increasing. With avionic devices as the application background, the modeling of the remote intelligent fault diagnosis system (RIFDS) based on multi-Agent theory is researched, including the frame model, logical model and soft architecture. The key problems that need to be resolved for the realization of the system are also discussed.
Study on ZUPT Technology Applied in SINS
Authors: Dai Xing Xing , Xie Ling , Mao Yu Liang , Song Chun Lei
Published: July 2012

Zero Velocity Update (ZUPT) is an essential method of error control in Stapdown Inertial Navigation System (SINS), which is extensively used because of its cheapness and efficiency. ZUPT uses the output of velocity error of SINS when the carrier is parking, to update the errors of other items in SINS. This method can improve the position and direction precisions of SINS. Kalman filter is chosen as the method of ZUPT to correct the velocity and position errors in SINS in this article. The method of ZUPT based on Kalman filter is applied to the vehicle experiment. The results of the vehicle experiment indicate that the ZUPT based on Kalman filter is efficient and powerful in error control, and the Kalman filter designed based on SINS is proper.
The Study on Bridge Coupled Vibration System Analysis Model
Authors: Xia Xiao Hui , Xia Chun Yan
Published: July 2012

On the base of modal synthesis theory, the self-compiling vehicle-bridge coupling vibration analysis program was used to analyze the vehicle dynamic response and passing vehicle riding comfort of cable-stayed bridge. Compared with the impact of different factors on vehicle riding comfort, this method provides a useful theoretical reference to correlated evaluation research and management maintenance. The influence of driving speed on comfort is not obvious. The research makes reference to correlated project evaluation in procedure and method.
DDoS Attacks for Ad Hoc Network Based on Attack Cluster
Authors: Yan Yao , Xu Rui
Published: July 2012

Show the definition of Ad Hoc network attack cluster, and propose a new method of DDoS attacks for Ad Hoc Networks, which can accurately attack the target node, demonstrate no redundant aggressive behavior compared with the traditional attack and reduce the detection rate of aggressive behavior. Use NS2 simulation platform to build Ad Hoc network simulation scenarios with dynamic topology, and simulate DDoS attacks in this environment; The simulation results show that the new DDoS attack method can effectively reduce the communication ability of the Ad Hoc network, and increasing the attack node density will strengthen the attack effect.
Research on Hyperspectral Data Classification Based on Quantum Counter Propagation Neural Network
Authors: Hou Xuan
Published: July 2012

It proposes the model and learning algorithm of Quantum Counter Propagation Neural Network and applies which in hyperspectral data classification as well. On one hand, introducing quantum theory into the structure or training process of Counter Propagation Neural Network with regard to improving structure and capacity of Classical Neural Network, enhancing learning and generalization ability of it. On the other hand, establishing a new topological structure and training algorithm of Quantum Counter Propagation Neural Network by the means of quoting the thought, concept and principles of quantum theory directly. To complete the experiment of hyperspectral data classification with three ways and the result shows that effects of Quantum Counter Propagation Neural Network is superior to the traditional classification.
Application of Machine Vision System in the Precision Inspection
Authors: Liu Yin Xia , Zhou Ping
Published: July 2012

In order to promote the application and development of machine vision, The paper introduces the components of a machine vision system、common lighting technique and machine vision process. And the key technical problems are also briefly discussed in the application. A reference idea for application program of testing the quality of the machine parts is offered.
The Decision Support System of College Training
Authors: Zhou Chun Hua , Chen Chu Xiang , Wang Yun Cheng , Yao Shi Jun
Published: July 2012

According to the characteristics of college training and requirements of the society for talents, the decision support system of college training is designed in this paper. Targeted at graduates’ employment, a data warehouse for college students is set up and online analytical processing and data mining are conducted so as to find out the key factors that affect graduates to find a job. The experimental results are in line with the reality, which shows that decision support system of college training is a powerful auxiliary decision-making tool.
Design and Implement of Data Acquisition System Based on Reconfigurable Computing
Authors: Xiong Zhi Wen , Xu Chen Guang , Zeng Hong
Published: July 2012

Data acquisition begins with the physical phenomenon or physical property to be measured. Examples of this include temperature, gas pressure, and light intensity, and force, fluid flow, regardless of the type of physical property to be measured. Physical property converted into digital, and then by the computer for storage, processing, display or printing process, the corresponding system is called data acquisition system. With the rapid development of computer technology, data acquisition systems quickly gained popularity. A variety of products based on digital technology have been created. Digital System spread quickly; it’s mainly the following two advantages: the first is the digital processing flexible and convenient; the second is a digital system is very reliable. The main idea of Reconfigurable computing technology [1] is using the FPGA [2][3] allows the system has a dynamically configurable capacity, suitable for harsh environment applications, improve the speed of data processing. By the use of dynamic reconfigurable FPGA devices can be realized on the hardware logic function modification, application of reconfigurable computing technology can improve the speed of data processing. Data acquisition system is widely applied in many fields, and often used the abominable working environment place. The reconfigurable computing technology, can greatly improve the data acquisition system reliability and safety. The paper introduces a kind of multi-channel data acquisition system based on USB bus and FPGA, the factors affecting the performance of system are discussed, and describes how to use reconfigurable computing technology to improve the efficiency of data acquisition system while reduce energy consumption. The system in this paper uses AD's AD9220, ALTERA's EP1C6-8 and IDT's IDT70V24, Cypress’s CY7C68013.
Facial Feature Location Based on Improved ASM
Authors: Qin Xi Wen , Zhang Hong Yu , Dong Xiao Gang
Published: July 2012

It makes a series of improvements of the traditional oriented way of human face, which is based on ASM. First, we orientate some outstanding feature points on the basis of the results of face test, then make use of these feature points to initialize model. Second, we get some statistics information of the edge in the training process and take a vertical range of the edge in a feature point. According to the scope of positioning, we looked at the local search results on its position before reconstruction the local adjust, thus preventing the search results from departing from the feature pointed have orientated.
Signature-Encryption Scheme: A Novel Solution to Mobile Computation
Authors: Bao Hai Yong , Xie Man De , Cao Zhen Fu , Hong Shan Shan
Published: July 2012

Mobile communication technologies have been widely utilized in daily lives, many low-computing-power and weakly-structured-storage devices have emerged, such as PDA, cell phones and smart cards, etc. How to solve the security problems in such devices has become a key problem in secure mobile communication. In this paper, we would like to propose an efficient signature-encryption scheme. The security of the signature part is not loosely related to Discrete Logarithm Problem (DLP) assumption as most of the traditional schemes but tightly related to the Decisional Diffie-Hellman Problem (DDHP) assumption in the Random Oracle Models. Different from the existing solutions, our scheme introduces a trusted agent of the receiver who can filter the “rubbish” messages beforehand. Thus, with high efficiency in computation and storage, it is particularly suitable for the above mobile devices with severely constrained resources and can satisfy the security requirements of mobile computations.
Analysis and Study of Multi-Address-Transport (MAT) Based on IPv6
Authors: Zhang Zhong Hao
Published: July 2012

This paper proposes the concept of Multi-address-transport (MAT) communication model in IPv6 which allows one server to transport a packet to several nodes at the same time without increasing the router’s burden. This model can achieve dynamic join and leave of this group without restrictions of physical location and all happened on servers and clients．In addition this model can overcomes multicast’s shortcoming and retains its advantage. This model need not any new hardware, just need modify software a little, and it have good Compatibility, it can run well even if some machine don’t modify its software, because it works on router that has been modified and passes through router not modified like the original. And, it is particularly suited to the increasingly popular BT transmission.
Characteristics Modeling and Simulation of Ship-Radiated Noise
Authors: Xu Hui , Xu Hai Qiao , Zhang Bi Yin
Published: July 2012

Since the importance of ship-radiated noise simulation in onshore simulation training and digital sonar development, we establish a mathematical model of ship-radiated noise on the basis of analyzing the causes and characteristics for each of its components, and then apply the model on simulating each signal component in turn. Additionally, for improving the versatility of the model while reducing the complexity of the simulation, a design method for specific frequency response filter based on window function is used to realize the simulation. The simulation results demonstrate the effectiveness of the approach.
Design and Implement of Auto-Scaling System Based on Eucalyptus Cloud-Computing Platform
Authors: Wang Wei Wei , Li Jing , Guo Yuan Yuan , Song Hu , Liu Xin Chun
Published: July 2012

On-demand service is one of the most important characteristics of cloud computing. Cloud-computing services should dynamically and timely deliver computing resources, storage resources and network resources etc. to consumers according to user needs, and service level should be able to meet quality of service. Users only need to pay on demand; otherwise they have to maintain sufficient resources just in order to meet peak requirements, which can be costly. In this paper, we present the design and implementation of Auto-Scaling system and illustrate its system architecture, components and scaling algorithm. Finally, we test the system and the results show that it can be capable of handling sudden load surges, delivering resources to users on demand, saving cost for users and improving resource utilization.
A Model of E-Commerce Credit Evaluation Based on Cloud Theory
Authors: Liu Yu , Wang Chang Jin , Wang Feng Qin
Published: July 2012

Traditional evaluation methods do not consider that e-commerce credit evaluation is inherently uncertain and ambiguity .This kind of method makes the evaluation results unnatural. In this paper, a model of e-commerce credit evaluation based on cloud theory is presented. It can transfer quantitative data to qualitative data by cloud transform and cloud maker and matches the index for rules by cloud reasoning engine. If this model is used to explain the result of evaluation, the result could be easier to understand.
Design and Implementation of Interactive TV Portal Based on Ajax and Jquery
Authors: Zhao Xua Nang , Deng Hao Jiang , Liu Xue
Published: July 2012

To solve the problems of long-time response and data redundancy in EPG obtaining of current interactive TV Portal, a new Portal system towards interactive TV terminals is designed and accomplished based on Ajax technology and jQuery frame. This system realizes asynchronous and cross-domain transfer of page information in batches, which also lays the foundation of real-time refresh of the page. Project results suggest that response time is shortened and resources are efficiently utilized while displaying and playing functions are ensured.
The Implementation of the Internal Control Management Information System
Authors: Song Xiao Hua , Wang Li Xiao , Ye Cai Qin
Published: July 2012

As the competition increases sharply in the market economy, enterprises are facing increasing business risks and uncertainties which needs to improve the internal control. Currently information technology is developing rapidly. The implementation of internal control by the information system will become a trend. This article analyzes the problems which the internal control management information system in the enterprises may encounter in the implementation; the potential risks from the business process and develop the appropriate measures.
An Algorithm to Packing Unequal Spheres in a Larger Sphere
Authors: Zeng Zhi Zhong , Huang Wen Qi , Xu Ru Chu , Fu Zhang Hua
Published: July 2012

We consider the problem of packing unequal spheres into a larger sphere as dense as possible. This problem is seldom researched so far as we know, but its importance and real world applications have been widely revealed. In this paper, we present a method using the techniques of Tabu search, Quasi-human basin-hopping strategy, and BFGS method as its components to resolve this problem, and get some solutions for a serial of thoroughly selected instances.
Dynamic Resource Allocation Algorithm in Parlay Multi-Service Environment
Authors: Wang Qin , Wang Jun Ping , Zhu Qi Liang
Published: July 2012

In the next generation network, there are more and more types of service. And the resource allocation control is more and more difficult. So it is very useful to do some research in this field. An algorithm which is flexible and adaptive can make the parlay gateway works better. In this paper a proved adaptive and sensitive resource allocation algorithm has been presented in the environment of Parlay multi-service. The simulation results indicate that this algorithm can satisfy the requirements of different kinds of service. The Parlay gateway can make full use of resource using this algorithm.
Research on Grid Scheduling and Resources Selection Algorithm
Authors: Bai Qing Hai
Published: July 2012

Grid, as a new tool for solving problems, is applied to science, engineering, industries and commerce. More and more application programs are making use of grid infrastructure to meet their needs of computing, storage and other aspects. The effectiveness of a grid environment depends on the effectiveness and efficiency of its scheduler. Grid scheduling is the process that maps grid jobs to the resource in multiple administrative domains. The article does research on the principles and methods of grid scheduling and gives a description about grid resource section by way of quantitative evaluation.
The Hardware Implementation of a Lightweight Block Cipher Algorithm and a Message Authentication Algorithm
Authors: Hu Yi Kun , Qin Zun Yang
Published: July 2012

Among the block cipher algorithms, AES or DES is an excellent and preferred choice for most block cipher applications. But AES and DES are not very suitable for hardware implementation because of the high cost that they require large areas of routing and the processing efficiency is low, relatively. So lightweight cipher algorithms come into beings, among which PRESENT is very competitive. Along with the structure of a message authentication algorithm ALRED, a new family of Tunable Lightweight MAC based on PRESENT is proposed, that is TuLP. However, PRESENT is not able to resist side channel attack, so is TuLP, of course. For the above reason, in this paper, we provide an improvement of PRESENT by inserting random dummy cycles as well as shuffling to strengthen the security of PRESENT against side channel attacks. We will implement PRESENT and TuLP in Verilog and do simulation on Xilinx ISim platform. At last, we would like to provide the power analyzing of Xilinx XPower.
Lightweight Design and Analysis of Support Structure of Certain UAV Engine
Authors: Xing Xiang Liang , Liu Bo , Han Xue Feng , Jia Hong Guang
Published: July 2012

Support structure of UAV (Unmanned Aerial Vehicle) engine is the important support for UAV engine, playing a support role and bearing extremely complex load, so its lightweight, strength and dynamic characteristics have a great influence on high performance of UAV. This paper focuses on UAV having the requirement of high performance and stability to the support structure of engine, and uses the software of MSC.Patran and MSC.Nastran and topology optimization criterion to lightweight design and analysis the support structure of UAV engine under the premise condition of existing constraints. Then the static strength and modal are analyzed for the result of lightweight design, and the strength of the model and dynamic characteristics are verified.
A Synthetically Improved Method Based on Apriori Algorithm
Authors: Zhang Min , Hou Yu , Yao Liang Wei
Published: July 2012

There are some disadvantages of the Apriori algorithm，such as too many scan of the database and many redundant middle itemsets to be generated. In this paper, we propose an improved algorithm, OApriori, with a synthetical method: (1) pruning strategy, (2) connection strategy, (3) reducing the scanning scale of database. We have performed extensive experiments and compared the performance of two algorithms. It was found that the improved algorithm reduces the counts of unnecessary candidate itemsets, accelerates the speed of the algorithm.
An Algorithm Design and Implementation of Connect6
Authors: Shi Wei Yi , Shen Yun Fu
Published: July 2012

The new Connect6 game was launched and received the widespread attention in recent years. For the problems existing in pattern judgment way and in 6-8 windows in some literatures, the algorithm of Connect6 is studied by considering the attack and defensive characteristics of the Connect6. By the new 6-8 window approach proposed here, the evaluation function which determines the evaluation value is designed and implemented by calculating the changing quantity of the assessed values of the chessboard before and after the falling a stone. Based on this, an optimal Connect6 program is designed and implemented based on the PVS algorithm and the transposition table optimization, history heuristic optimization, null-move pruning optimization as well as iterative deepening optimization. The pruning rate of nodes in game tree comes to more than 98%. The actual playing of the chess indicates that the program has the strong chess strength.
Air Purifier Based on Sensorless DC Motor and Composite Photocatalyst Technique
Authors: Song Wei , Li Ming , Xie Ning
Published: July 2012

This project is purposed to design an air purifier based on composite photocatalyst technique. Photocatalyst could work normally only in limited condition with ultraviolet light and light intensity strong enough. In order to overcome the deficiencies above, this project uses composite photocatalyst technique to improve purification efficiency of the air purifier. The composite photocatalyst technique comprehensively combines photocatalyst technique and traditional air purification technology. Moreover, the utilization of multi-thread algorithm has decreased the response time of this design to great extent. The brushless direct current motor without hall sensor charged by direct current frequency conversion technique decreases the noise of the air purifier, prolongs its life, and protects environment by saving energy.
Research of Random Drift for MEMS Gyroscope Based on Gray System and ARMA Model
Authors: Liu Zhao Hua , Chen Jia Bin , Mao Yu Liang , Song Chun Lei
Published: July 2012

Due to the precision of MEMS gyroscope is currently low level, even in low precision dynamic attitude measurement system, its error is also need to be estimated and compensated. Random drift is the one of the most important factor affects MEMS Gyro’s precision. At the same time, it is a non-stationary, weak non-linear and time-variant random signal. For improving precision of gyro and reducing effects of random drift, this paper used gray GM(1, 1) model to extract established tendency signal, and used power spectral density (PSD) to identify and extract the hidden periodic weak signal, then used ARMA method to model gyro’s random drift. As the example of LCG50 MEMS gyro, the simulation experimental results show that using this method can reduce the random drift and enhance precision of gyro.
Study on a Method by Using VB for Failure Diagnosis of Mechatronical Equipments
Authors: Zhen Jiu Jun , Yang Hong Ke
Published: July 2012

In general, the failure diagnosis and maintenance work of mechatronical equipments have greater difficulty, especially for less experienced technician. However, with the rapid development of science and technology, the mathematical analysis and computer can help us. So, According to the principle, structures and fault characteristics of mechatronical equipments, a method based on combination of the mathematical logic analysis theory and VB software is proposed. The principle of fault diagnosis methods, procedures and examples are included in this article. The results show that the method can effectively improve the efficiency and reduce errors caused by the additional diagnosis of faults.
Feature Selection Method Based on Parallel Binary Immune Quantum-Behaved Particle Swarm Optimization
Authors: Chen Chao , Zhu Hao Dong
Published: July 2012

In order to enhance the operating speed and reduce the occupied memory space and filter out irrelevant or lower degree of features, feature selection algorithms must be used. However, most of existing feature selection methods are serial and are inefficient timely to be applied to massive text data sets, so it is a hotspot how to improve efficiency of feature selection by means of parallel thinking. This paper presented a feature selection method based on Parallel Binary Immune Quantum-Behaved Particle Swarm Optimization (PBIQPSO). The presented method uses the Binary Immune Quantum-Behaved Particle Swarm Optimization to select feature subset, takes advantage of multiple computing nodes to enhance time efficiency, so can acquire quickly the feature subsets which are more representative. Experimental results show that the method is effective.
Study of Heat Transfer Parameters in the Laminar Cooling Process for Hot-Rolled Strips
Authors: Pian Jin Xiang , Hou Jing , Li Jie Jia , Ma Bin
Published: July 2012

The laminar cooling process for the hot-rolled strip is very complex, and the identification of k related to the heat transfer is critical to improve the mathematic precision. So a study of heat transfer parameters is carried in the paper, and the proposed approach is based on the hybrid multi-intelligence technology, where the RBF neural networks, CBR have been used to obtain the parameter estimates. A number of tests using industrial data have been conducted where desired numerical results have been obtained.
Research of GDA Based on IEC 61970 and CORBA
Authors: Wang Ting , Zhang Dong Liang , Tao Zhi Jian , Wang Ping
Published: July 2012

On the basis of in-depth study of the power system enterprise applications with distributed and heterogeneous characteristics, a solution to cope with an integrated data conversation platform is proposed against the background of power dispatching automation system which the data modeling and software component interface is not mature enough. This article also gives software design methods based on the CORBA specification and IEC 61970 standards for power system automation and elaborated the task execution flow of generic data access (GDA); at last corresponding test is also given. At the same time the development process for CORBA object services, resources sequence caching, distributed object calls and other important issues are given a detailed solution.
Research of Object-Oriented Design Process Based on UML
Authors: Dong Ai Mei
Published: July 2012

System analysis is the most important Part of the software life cycle. A successful software system is always based on good analysis. Modeling with UML has become a trend in object-oriented analysis and design. This paper firstly discusses object-oriented software development process based on UML (Unified Modeling Language), then describes in details object-oriented software design process, and lastly applies the design process into business personnel management system.
Study on the Measurement Method and Safety Design of Ultrasonic Cleaning Equipment
Authors: Wang Cai Yuan , Zhou Ai Hui , Xia Zhen Sheng
Published: July 2012

To the question that it was hard to measure and verify the safety design rationality of the performance parameters for the ultrasonic cleaning machine, the destructive effect mechanism of the ultrasonic cleaning was analyzed. It was indicated that the cleaning power and time were the two main factors for damaging the insulating layer of the cleaning objects. The measuring technology was presented by aluminum foil, and it analyzed feasibility and an area assessment method for the measurement method by aluminum foil. The practical long time test of the motor demonstrated that the measurement method by aluminum foil can provide safety design data support and experimental verification to the performance parameters design of the ultrasonic cleaning machine.
Design of FPGA-Based Fault-Tolerant Embedded System
Authors: Xiong Zhi Wen , Wang Wen Feng , Zeng Hong
Published: July 2012

Fault tolerant is one of major requirements for embedded systems. As the embedded systems become more and more complex, more chances for various fault. When design embedded system developer has to handle these faults. Before handling faults designer has to identify and understand the types and nature of faults.Faults is the sources for low dependability, faults can be hardware and software. Hardware faults can be distinguished from systematic faults like software or design errors. The Fault can be deleted, such as extensive testing or formal verification and tolerated by fault tolerance techniques. We restrict ourselves to the problem of fault tolerance and refer to other methods for troubleshooting.This paper discusses a new design method about the fault tolerant system of embedded system. We designed a fault tolerant system of data acquisition system in dynamically re-configurable FPGA. The experiment results show that the system not only be able to higher self-adaptive ability and reliability, but also can Through the FGPA to complete a specific algorithm.
Position Sensorless Detection of SRM Based on BP Neural Network
Authors: Zhou Yong Qin , Wu Xiao Gang , Yu Teng Wei , Bai Chao , Li Wen Juan
Published: July 2012

Theory of SRM position detection based on exciting pulse voltage to no conduction phase is analysised, and a combination with BP (back propagation) neural network model to predict SRM rotor position without sensorless is proposed. Training sample and test sample can be obtained by SRM detection system with position sensor, with response current as input, and the rotor position as output, a single input and a single output of BP neural network model is built. Mapping between response current and rotor position are obtained by training BP neural network, and the rotor position prediction is realized, test sample is used to verify the BP neural network model. Simulation results show that this approach improves the detection accuracy compared with the method by injecting exciting pulse voltage.
Design and Realization of Embedded High-Speed Image Stabilization Device Base on FPGA+DSP
Authors: Diao Jie Tao , Xing Jin Ling , Yu Hong Qi , Wang Yi Nan , Yang Yang
Published: July 2012

A design and realization of embedded High-speed image stabilization device is present to remove unwanted shaking phenomena in the image sequences captured by the high-speed industrial camera with 256x256 pixel @1000 frames per second, 8bit, Gray scale. Each module design of the mentioned device is introduced in detail. The interested image sequences are transferred through camera link interface to the device, buffered, preprocessed by an FPGA, and processed by DSP to achieve two-dimensional motion vector which is exported by a digital-to-analog chip. The test result shows that the image stabilization device works stable, real-time, high-accuracy.
Enhancement of Acoustic Field Aberration for Underwater Forward Detection with Experimental Verification
Authors: Lei Bo , Yang Kun De , Wang Yong
Published: July 2012

When an object crosses the source-receiver line, a weak acoustic field aberration is produced. However, it is often overwhelmed by the fluctuation of direct blast. A principal component analysis of stable portion of beam output on vertical receiver array is proposed to enhance the field aberration for forward detection. A lake experiment utilized a vertical receiver array spanning the water column was conducted. A 10 kHz pulse was transmitted successively, and the field aberration caused by the forward scattering of the crossing object was observed. The beam output waveform at the horizontal direction is processed with the proposed method, and the field aberration about 10dB above the background acoustic field is achieved, while the maximum aberration is only about 2dB above the background field before processing.
Finite Element Method Used in the Calculation of Earth-Rock Dam Seepage Reflections
Authors: Hua Jing , Yang Hua Shu
Published: July 2012

This paper analyzes the problems which exist in finite element calculations of the earth dam seepage which is free surface solution, cell subdivision improper, the transformation of the free surface boundary conditions and the permeability coefficient values at the interface of different materials, boundary conditions and other issues. Put forward the corresponding solution. Applies common general finite element software to calculate the seepage. Works in conjunction with a stable levee seepage analysis and get better results.
Multi-Function Manipulator
Authors: Wang Zu Lin , Ouyang Jian Fei , Fang Qiang , Liu Yuan
Published: July 2012

This paper is for ordinary lathe supporting and design the capture of manipulator. Practice has proved, industrial robots can replace the hands of heavy labor, significantly reduce the labor intensity, improve working conditions, and improve labor productivity and automation level. In addition, it can be in high temperature, low temperature, deep water,cosmos, radioactive and other toxic, pollution environment conditions operation, more shows its superiority, with broad prospects. In the paper, the structure of the manipulator model design and Cortex-M0 micro controller (hereinafter referred to as M0) as the main controller in this paper. With multiple steering gear as the basis, make manipulator model, through the realization to the output M0 PWM control more than the steering gear, and finally achieve the acquirement manipulator workpiece, and the workpiece in designated spot.
Study of NC Frequency Source Based on the GPS Atomic Clock System
Authors: Xu Tian Qi , Lei Hai Dong
Published: July 2012

This paper presents a new VCXO frequency source based on the GPS module, atomic clock in system and loop compensation circuit, the accuracy of the system, long-term stability, and short-term stability can be improved because of its new structure. Specific description of the closed-loop lock works, including the compensation circuit of the machine.
Study on Aerospace Layering Time Synchronization Architecture and Time Synchronization Algorithm
Authors: Huang Fei Jiang , Lu Xiao Chun , Yang Jun , Shan Qing Xiao , Zhou Yong Bin
Published: July 2012

The rapid development of various kinds of aerospace application systems requires the appropriate high-accuracy time and frequency standard. This problem can be effectively solved by establishing suitable time and frequency standard in aerospace. Based on the establishment of aerospace satellite visual model, the simulation of satellite visual time on 3-layer constellation structure, including GEO satellite, IGSO satellites and MEO satellites, has been conducted. The visual features of this constellation have been gained. Combining with the major influencing factors of satellite clock correction error, aerospace time synchronization architecture on the basis of layering has been proposed. The time synchronization algorithm in line with this architecture has been researched. The results show that aerospace time frequency standard established based on this layering time synchronization architecture can meet the demand on high-accuracy time frequency of future aerospace application systems.
Wet Modal Analysis of a Deep-Sea Autonomous Underwater Vehicle
Authors: Xiang Ye , Zhang Lian Hong , Wang Yan Hui , Zhang Hong Wei
Published: July 2012

When cruising underwater, the Autonomous Underwater Vehicle (AUV) oscillation will affect some sensors’ measuring precision. In this paper, the method of equivalent entities is used to build the AUV’s solid model, and the AUV’s fluid-solid coupling system together with its wet modal is analyzed using ANASYS software. In addition, the AUV’s bending mode and breathing mode under different depths are discussed, which will reflect the changing trends of AUV vibration frequencies during operation. The conclusion can provide the theoretical basis for the AUV structure design when certain measuring task is performed using sensors.
Analysis of Hydrodynamic Noise around Acoustic Modem on the AUV Using Hybrid LES-Lighthill Method
Authors: Liu Tong Hui , Wang Yan Hui , Guang Zhu
Published: July 2012

Acoustic modem is one of the most important sensors on the deep sea AUV. A good performance of the acoustic modem has great effect on the safety and operation of deep sea AUV. According to the construction of deep sea AUV, acoustic modem is installed in the cavity behind the GPS antenna, it would cause flow noise around the acoustic modem and thus interference will occur when the communication is established between deep sea AUV and surface. Flow-induced noise around the acoustic modem is studied in this paper. Firstly the unsteady flow around the acoustic modem is studied by large eddy simulation (LES) method. Secondly based on the resolved information of flow field, acoustic noise distribution is studied using equivalent acoustic sources method. Compared with different positions of GPS antenna, flow noise distribution around the acoustic modem and the effect on communication is investigated. Then acoustic modem layout on the AUV is optimized.
Vibration Signal Extraction of Rotating Machines Based on the Analysis of Degree of Cylcostationary
Authors: Wang Yu Rong , Wu Tian Xing
Published: July 2012

When early faults occur in rotating machine, the vibration signal being extraction the often contain heavy background noise .In this paper the analysis of degree of cyclostationarity (DCS) was proposed to vibration signal extraction of rotating machine. This method can overcome the shortcoming of Hilbert transformation that will be influenced by many factors, such as end effect, sampling frequency and the added noise in signal. The research results show that the DCS can not only extract vibration signal but also suppress the added noise in the signal. Therefore more accurate fault signal will be extracted and detected through this new method.
New Electromagnetic Imaging Tool Introduced for Corrosion Detection
Authors: Zhong Xing Fu , Wu Ying Xing , Chen Jian Qiao , Abakumov Alex
Published: July 2012

The new Electromagnetic Imaging Tool (EMIT) is introduced in this study. It is also described that the basic inspection theory, system structure and applications. The EMIT can determine whether metal loss or casing damage has occurred internally or externally. A 3D casing image can be supplied, including horizontal, vertical profile. The experimental results show that the EMIT has a “high-resolution” for MFL method in the casing well because of the steel brush structure. The minimal diameter of the inspection hole is 4 mm, and the thickness determination error of casing wall is 0.4 mm. A number of examples from oilfield are presented.
Research on the Electric Enclosed Loading Tester of Gearbox
Authors: Zhang Zhen Li , Zhou Fa Zhu , Chen Jian
Published: July 2012

A project about electric enclosed loading test system of gearbox is put forward by comparison. The structure and working principle of the system is introduced during the Control loop and the microcomputer monitoring software architecture figure of the system is given out. The test results show that the loading system runs steadily, loads conveniently, saves energy obviously, and satisfies the requirement of design.
Numerical Simulation on Aerodynamic of the Wing in Ground Effect
Authors: Wu Rong , Liang Feng
Published: July 2012

Aerodynamic characteristics of the wing NACA5312 in ground effect are investigated with the numerical simulation method. The N-S equations and the k-ε turbulence model are solved by the finite volume method in CFD software. This paper computes the flying states under different clearances, steam velocities and angles of attack. Compared with results under the unbounded flow, it studies the relations between the aerodynamic performances and the angles of attack, the steam velocity, and the relative heights. The aerodynamic performances include the lift coefficient, drag coefficient, and lift-drag ratio.
Numerical Simulation of Low Engine Order Excitation in a Transonic Compressor
Authors: Zhang Bo , Liu Yang Wei , Liu Bao Jie
Published: July 2012

A full-annulus unsteady quasi-3D simulation for a transonic compressor was conducted to investigate the low engine order excitation sources. A special inlet total pressure distortion was used in the simulation to account for the effect of non-axisymmetric tip clearance. The unsteady aerodynamic forces were obtained by integrating the static pressure along the blade surface. Furthermore, the effect of downstream rotor detached shock on upstream stator was analyzed. It was shown that the unsteady aerodynamic excitation of the rotor was subjected to the first two harmonic frequencies of the inlet distortion, and the adjacent stators’ basic frequency and lower harmonics. It was found that the detached shock had a significant impact on the surface static pressure distribution of the upstream stators.
Research on Torque Distribution Strategy for ISG Hybrid Electric Cars
Authors: Wang Xu Dong , Zhang Hai Xing , Yang Shu Cai , Zhou Yong Qin , Liu Jin Fa
Published: July 2012

Based on the configuration and working state analysis of the ISG hybrid electric cars, the torque distribution strategy of a hybrid system is designed to delineate the maximum and minimum work torque curves of the engine, achieve optimization of engine’s range so as to make sure the target torque of the engine and ISG motor, and finally through the calibrated driving characteristics MAP and battery SOC state to achieve the calculation of total vehicle torque demand. Taking the Hafei Saibao ISG hybrid car as a test model, the test of fuel economy and emissions carried out under specific conditions showed that using the torque distribution strategy has increased by 12.8 % of the ISG hybrid car fuel economy and improved emissions performance to some extent compared to the traditional Hafei Saibao cars.
The Analyze and Design of Focusing System for Space Camera
Authors: Yu Tao , Song Kei Fei
Published: July 2012

In order to control the focal plane and guarantee the imaging quality of space camera, the focusing system was proposed. Firstly, the reasons of defocusing were analyzed and a solution method was given. Secondly, the system structure and operating principle were introduced. Thirdly, the system design was presented in detail. Finally, the system was experimented. Experimental results indicate that the defocusing amount of camera can be controlled below 10 um and the focusing system satisfies the requirement of system design.
Application for High-Definition Intelligent Video Surveillance Based on WPON and SIP
Authors: Wang Shi Wen , Xie Bo
Published: July 2012

High-definition intelligent video surveillance system of Henan Power is constructed in 220KV&500KV substation with uniform marginal pattern, multi-level management and image resources sharing. The video sever control and communicate with the monitoring equipment at the substation with WDM-PON channel based on SIP protocol, and can achieve a truly high-quality picture format up to D4(1280*720). Gateway Protocol is researched and developed to convert SD (Standard Definition) video image with different formats to unified H.264 format. The SD and HD video image access to video surveillance platform based on SIP protocol, then give solutions to the existing substation video surveillance platform with low transmission rate, incompatible interface protocol and low quality video image. Furthermore, intelligent analytical processing for data traffic carrying feeder in substation, icing equipment, transmission line galloping and meteorological monitoring, together with the HD video image transmitted on WPON. Aid decision is made for power network production operation and emergency support.
Design of Position Control for Linear Switched Reluctance Motor
Authors: Yang Song , Ma Hang , Yang Jun You , Shen Huai Yang , Chang Sheng Quan
Published: July 2012

This paper presents a high-precision position control system for a linear switched reluctance motor (LSRM) based on dSPACE real-time control platform. The LSRM has a very simple structure and it can be manufactured easily, and there is no need for magnets. The system utilizes dSPACE platform as the controller and generates the real-time code for the control algorithm, tuning the control parameters on line and PD algorithm is implemented. The results show that control algorithm can substantially reduce position error. The DSP-based position control scheme is implemented and experimental results prove the effectiveness of control design method.
A Position Control Scheme Using High-Order Iterative Learning Control for Permanent Magnet Linear Motor
Authors: Yang Song , Ma Hang , Yang Jun You , Shen Huai Yang , Chang Sheng Quan
Published: July 2012

A high-order Iterative Learning Control (ILC) strategy is designed for Permanent Magnet Linear Motor (PMLSM). This iterative learning controller is designed to high-order open and closed loop PID-type. This paper gives the convergence conditions of the proposed controller and proves that the tracking bound is determined by the bounds of state uncertainty and output disturbance to the system. The proposed ILC strategy result shows that position precision of PMLSM in point-to-point motion can be effectively improved with this scheme. The experiments demonstrate that the presented ILC strategy is effective and robust.
Simulation and Design of Double Close-Loop DC Motor Control System Based on Matlab
Authors: Xiong Jing Jing , Feng Zhen , Liu Jiao Yu
Published: July 2012

In this paper, based on the principle of the speed and current double closed loop DC regulating system and the requirement of the static and dynamic performance, we calculate time constant of the regulator, select the structure of the regulator to calculate related parameter and then correct its parameters, and model system and simulation by using Simulink, analysis waveform and debug to find out the optimal parameters of the system regulator to guide the actual system design.
Simulation Study on Harmonic Current Based on Matlab
Authors: Cao Neng , Lai Jin Gang , Liu Jiao Yu
Published: July 2012

This article use emulation software MATLAB to design the Fast Fourier transform (FFT) algorithm. And utilize the algorithm to analyze the current frequency of power grid. This paper draws the block diagrams of the algorithm realization, and explains part of the thought of the procedures of the software realization under MATLAB environment, and also establishes the complete concept from algorithm theories to program realization. Then, analyses the harmonic component based on the procedures. Finally, comes to a conclusion that we can reduce the amplitude errors by adding the window function.
An Improved FFT Algorithm and its Application in the Measurement of Grounding Resistance
Authors: Chen Wen Yan , Tuo Hang
Published: July 2012

For the problems of noise and clutter interference in the measurement of grounding resistance, the article designs a grounding resistance measurement method based on an improved FFT algorithm. We deduce the harmonic amplitude correction formula which can more accurately measure the frequency of the interference signals and the amplitude of the effective signals, and thus improve the measurement accuracy of grounding resistance. This paper also devises a grounding resistance measurement scheme combining the algorithm and the variation-frequency method. The simulation results and the validation of experimental data show that, the algorithm evidently reduces the noise and improves the measurement precision. The algorithm is of high practical value to the grounding resistance measurement.