JOURNAL OF BEIJING INSTITUTE OF TECHNOLOGY

Multi-Channel Force Control System for Static Loading

CHEN Cai-ke, WANG Jun-zheng, MA Li-ling, LI Jin-cang

2003, 12(S1): 1-6.

[Abstract](139)

Abstract:
An eight-channel force loading system is presented, which adopts position control system and force control system switching model, small flow servo valve controlled capacious cylinder system scheme, intelligent PID algorithm and distributed load approach. Through the analyses of the equivalent model of valve controlled cylinder force subsystem, a controller based on intelligent PID algorithm is designed, which is not sensitive to the variation of parameters such as environmental stiffness. According to the coupling of multiple load channels, a distributed load approach is employed in the superior monitor computer. Experimental results show that the system designed has high precision and robustness.

The μ Method to Robust Stability Analysis

LIU Juan, WU Qing-he

2003, 12(S1): 7-11.

[Abstract](206)

Abstract:
The robust stability of systems under both plant and controller perturbations is analyzed, with an emphasis on additivenorm-bounded perturbation. Choosing the interconnection matrix M makes Δ(s) block diagonal matrices and absorbing any matrix makes ‖Δ(s)‖∞<1, the problem can be recast into a small structured singular value (μ) problem. If 2S + F ≤ 3, μ(M) = infσ(DMD-1). In this paper, the main result is supωμ(M)=‖M‖∞, thus the structured singular value(μ) problem for robust stability of SISO systems subject to additive norm-bounded perturbation, can be recast into H∞ control problem. Moreover, robust stability of MIMO systems can be unified in the same framework.

ATMS Based Information Fusion Target Recognition Method

CHEN Wen-jie, DOU Li-hua, ZHANG Yu-he

2003, 12(S1): 12-15.

[Abstract](173)

Abstract:
The non-monotonic problem exited in information fusion systems is solved. Through the introducing of non-monotonic reasoning method, which was realized with ATMS, into the information fusion system, it gains the ability to process insufficient information with flexibility and non-monotonic behavior. In the simulation test of our system, our system manifests its ability of dealing the insufficient and contradictory information, which partly solves the decision dilemma brought out by the insufficient information in battle situations. The information fusion target recognition system can process the information in battle situation fast and with flexibility.

Intelligent PID Control of Pneumatic Rotary Actuator Angle Servo-System

Wang Peng Peng, Guang-zheng, Wu Qing-he

2003, 12(S1): 16-19.

[Abstract](130)

Abstract:
In order to solve the problems that make the orientation of pneumatic rotary actuator inaccurate, a newly intelligent PID control algorithm is proposed. Pneumatic rotary actuator angle servo-system uses electropneumatic proportional valve as control device, which changes the pressure of cavity and then pushes the actuator to revolve to the expected position. Using intelligent PID control algorithm, several special methods were put forward to overcome the connatural shortcomings of pneumatic system and make the rotary actuator track the expected value timely and accurately. Experimental results have shown that by using this intelligent algorithm, the performance index of system was improved greatly.

Design of Fuzzy Controller for Central Air Conditioner

XIE Juan, GENG Qing-bo

2003, 12(S1): 20-24.

[Abstract](156)

Abstract:
A structure of central air conditioning system in building and its running pattern are proposed in order to perform optimum energy saving strategy. The design of room temperature controller is taken as an example to discuss the design of fuzzy controller using common microprogrammed control unit (MCU) in detail. Based on fuzzy theory the query control tables fixed in read only memory (ROM) of MCU are established to realize the energy saving in the room temperature controller and the reasoning procedure is analyzed. The diagram of hardware design and the flow chart of software of room temperature controller are presented. The results show that the proposed method is practical and effective to achieve the energy saving goal.

Application of CAN Bus in Hotel Guest Room Service and Management System

XIONG Yun-fan, GENG Qing-bo

2003, 12(S1): 25-28.

[Abstract](165)

Abstract:
Technical features about CAN bus are described. One kind of scheme in Hotel Guest Room Service and Management System based on CAN bus is presented. The system's structure and main function are expounded. The work principle and design of the system's hardware and software are explained. The realization of the system's hardware and software is detailed from aspects of improving system's anti-jamming and fault self-examined capability, and the block diagram of each part's circuit is given. Finally, features of the system are summarized, and a comparison with the system based on RS485 was made to prove the advantages of the system. By practice, CAN bus in the system can transmit data steadily and reliably.

Intelligent Optimizing Control Used in Combustion of Boiler Boiler

GAO Yan, XIE Jian-Hua

2003, 12(S1): 29-32.

[Abstract](172)

Abstract:
In order to improve the efficiency of the combustion of boilers, an approach named self-optimizing which takes the temperature of furnace as the major signal to control the ratio between the wind and coal input is used. Our goal is to save energy. This method can be used to replace the one which uses zirconia as the monitor, so as to avoid its shortcomings, like expensive, ephemeral, and hysteresis. Equal step by step self-optimizing algorithm and variant step algorithm is also introduced. And the intelligent self-optimizing control algorithm is discussed. This intelligent algorithm is realized by utilizing fuzzy logic estimation method.

Wavelet Transform Approach to Segment Thermal Image

FU Meng-yin, ZHANG Chang-jiang, LI Jie, JIN Mei

2003, 12(S1): 33-38.

[Abstract](172)

Abstract:
An efficient multi-threshold approach to segment thermal image is given based on wavelet transform. The gray-level histogram of original image is obtained. In order to reduce the effect of noise, the gray-level histogram is smoothed by Bezier curve and Bezier histogram is obtained. One dimension stationary wavelet transform is done to the curvature curve of Bezier histogram. Positions of peak values of curvature curve in wavelet domain are adjusted from "fine-to-coarse" at all scales. The gray level values, which are located in adjusted peak values at all scales, are considered as segmentation thresholds. The gray level values of valley between peaks are considered as quantity gray levels. Optimal segmentation scale is obtained by a cost criterion. The results of experiment show that a target can be segmented effectively from complex background in thermal image by new approach.

Simulation System of Antiaircraft Gun to Intercept Cruising Missile

MOU Da-wei, CAI Tao, DOU Li-hua

2003, 12(S1): 39-43.

[Abstract](174)

Abstract:
The tactical assumption of antiaircraft gun system to intercept cruising missile is researched with method of digital simulation. At first the problem of target creation is discussed, Then the modeling of each part of antiaircraft gun system including fire control system, tracking system, shootable zone and calculation of external trajectory is dissertated detailedly. After establishment of simulation database, the forward relevant software design project is presented. The simulation system can be used to evaluate the effect of intercept missile by single gun, and integrate with other simulation system.

Simulation Platform for Greenhouse Environment Control System

CAI Zhen-jiang, ZHANG Juan, WANG Yu, SUN Chang-sheng

2003, 12(S1): 44-48.

[Abstract](165)

Abstract:
The simulation system is designed to imitate a greenhouse environment with the software on computer. The relation ships between greenhouse indoor environment, outdoor environment and environment conditioner are presented The energy balance equation and humidity balance equation of the greenhouse are givea In this system, the weather data is generated by computer according to the real weather data and rules in Beijing. The state of the devices can be dynamically decided based on the given intelligent control algorithm Then the parameters of the greenhouse environment are decided based on the greenhouse model that presented All the results are showed on the screen with kindly interface and stored to disk automatically.

Integrated Control System of Vehicle ABS/ASR/ACC Based onMC9S12DP256

ZHANG Jing-bo, LIU Zhao-du, SHI Kai-bin, ZHONG Qiu-hai

2003, 12(S1): 49-53.

[Abstract](178)

Abstract:
The integrated control system of vehicle ABS/ASR/ACC has been developed using the MC9S12DP256 single chip, which is the new Motorola 16-bit product in HSC12 family. The system including the main control module, the data collection module and the drive and fault diagnosis module is demonstrated and its data collection function is presented in detail. The system designed by the modularization can supervise the data, drive the valves and pump. The program can be debugged on line, which is steady and reliable validated by the large numbers of vehicle road tests.

Artificial Neural Network Performing the Forward Operation of Color Appearance Model

CHAI Bing-hua, LIAO Ning-fang, YANG Wei-ping

2003, 12(S1): 54-57.

[Abstract](171)

Abstract:
A method of the forward operation of color appearance (from colorimetric attributes to color appearance attributes) using an artificial neural network (ANN) is presented The neural network model developed is a multilayer feedforward neural network model for predicting color appearance model (CAM). This method greatly decreased the mathematical computation in color appearance prediction. The error backed-propagation (BP) algorithm was applied in the training of the neural networks, and it was trained and tested by the LUTCHI color appearance datasets which are the most comprehensive one in testing color appearance model. CRT was selected as a typical example in experiment because it is usually used as self-luminous object in fact, and several ways for choosing training samples were included and compared each other. The testing results show that the color appearance prediction using artificial neural network is well consistent with visual evaluation.

Novel Optical Analog-To-Digital Converter Based on Optical Time Division Multiplexing

WANG Xiao-dong, SUN Yu-nan, WU Jian, CUI Fang

2003, 12(S1): 58-61.

[Abstract](146)

Abstract:
A novel optical analog-to-digital converter based on optical time division multiplexing(OTDM) is described which uses electrooptic sampling and time-demultiplexing together with multiple electronic analog-to-digital converter(ADC). Compared with the previous scheme, the time-division multiplexer and the time-division demultiplexer are applied in the optical analog-to-digital converter(OADC) at the same time, the design of the OADC is simplified and the performance of the OADC based on time-division demultiplexer is improved. A core optical part of the system is demonstrated with a sample rate of 10 Gs/s. The signals in three channels are demultiplexed from the optical pulses.The result proves our scheme is feasible.

Real-Time Digital Image Stabilization Based on Contour

ZHOU Yu-bin, ZHAO Yue-jin

2003, 12(S1): 62-65.

[Abstract](153)

Abstract:
A new digital image stabilization method is proposed for real-time application based on image contour. The image intensities are projected to several gray levels by thresholding before extracting contour points. Matching position could be found using these contour points. All pixels are still used for refined matching near the matching position. This algorithm is more robust against changes in illumination and noise affection. The adaptive global motion judgement can remove the affection of intruding object. All those are realized on normally available PC.

ASIC Design of High-Speed Low-Power HDLC Controller

CHEN He, HAN Yue-qiu

2003, 12(S1): 66-69.

[Abstract](162)

Abstract:
Combined with the engineering requirement, a high-speed low-power ASIC design of HDLC controller based on RS-485 bus is given in this paper. On principle of Top-Down design, this ASIC design uses multi-techniques to reduce its die area and dynamic power, and overcomes some problems appeared frequently in application systems of the RS-485 circuits formed by the Standard Interface Chips. This design also improves the system reliability and reduces the system area.

Lifting Scheme Based SPIHT Still Image Coding

SHEN Li-jun, ZHAO Bao-jun, HE Pei-kun

2003, 12(S1): 70-74.

[Abstract](169)

Abstract:
In order to eliminate float-point operations for fast wavelet transform, an integer D9/7 biorthogonal reversible wavelet transform was accomplished by lifting scheme. The lifting scheme based wavelet transform can be finished by addition and shift simply. It improved the quality of reconstructive image and greatly reduced the computational complexity due to integer operation. It is suitable for real-time image coding on hardware such as DSP. The simulation results show that the lifting scheme based SPIHT is prior to traditional wavelet based SPHIT in quality and complexity.

Performance Analysis and Simulation of Higher Order Modulations for Ka-Band Fixed Satellite Communication

WANG Ai-hua, WANG Chun-ting

2003, 12(S1): 75-80.

[Abstract](168)

Abstract:
The performance analysis and simulation of spectrally efficient modulation schemes , MPSK and MQAM, for Ka-band fixed satellite communication system are provided. The effects of bandwidth limitation, nonlinearityity distortion and adjacent channel interference (ACI) in Ka-band satellite channel corrupted by additive white Gaussian noise (AWGN) are taken into account. The analytical expressions of the HER of coherent MPSK and MQAM signal are obtained and shown to be in good agreement with the simulation results.

New Solution on Distributed Hardware-in-the-Loop Radar System Simulation on HLA

LIU Wei, ZENG Tao, LI Hai

2003, 12(S1): 81-85.

[Abstract](137)

Abstract:
In the large-scale distributed hardware-in-the-loop radar simulation system based on HLA, a new solution of processing after acquisition is proposed, which separates the software subsystem from the hardware jammer subsystem by a response database, so as to settle the problem, that the software subsystem can not meet the real-time need of the hardware, with very little increment of code. And the data completeness and feasibility of this solution are discussed.

Solution for Hardware-in-the-Loop Radar Netting Simulation Problem by Utilizing Time Reversal Method

LIU Feng, ZENG Tao, Long Teng, LIU Wei

2003, 12(S1): 86-90.

[Abstract](169)

Abstract:
A new method of radar netting simulation with hardware-in-the-loop (HWIL) is introduced based on the idea of time reversal. It is the high authenticity, low cost and great simplification in design that the method does provide. Along with several paragraphs about the vital features, the model of probability is explained in an analytical way to find out the feasibility of this method.

Modified Approach to PGA Phase Averaging for ISAR Autofocus

HE Yuan, GAO Mei-guo, FU Tuo

2003, 12(S1): 91-95.

[Abstract](181)

Abstract:
A new approach to phase averaging in phase gradient algorithm (PGA) is proposed, which is based on the fundamental fact that the information of translational phase error is widely contained in every defocused scatterer in ISAR image. The new approach aims to choose strong scatterers for error phase averaging with a threshold rather than just simply to pick out the strongest point in each range cell, which is not necessarily real strong scatterers if in some range cells consists more than one strong scatterer and whereas in other range cells no scatterer at all. The results of processing real data are presented to confirm the validity of the proposed approach.

Building Intelligent DSS Based on Multi-Agent Cooperation

LIU Qiong-xin, LIU Yu-shu, GAO Chun-xiao

2003, 12(S1): 96-99.

[Abstract](130)

Abstract:
A general multi-agent architecture is proposed for intelligent decision support system (MAIDSS). The agent in MAIDSS is built based on an extension of BDI framework. Several agents form a team working together on a decision problem; several agent teams are defined to stand for the benefits of different people in the real world. The decision making process is based on multi-agent cooperation, and a logical framework for a team of agents cooperating to create the solution for the decision problem is discussed in detail.

Double Learning Algorithm in Bilateral Multi-Issue Negotiation under Incomplete Information

CAO Yuan-da, LI Jian

2003, 12(S1): 100-103.

[Abstract](172)

Abstract:
In order to enhance the efficiency in bilateral multi-issue negotiation under incomplete information, double learning algorithm that includes Q-learning algorithm and Bayesian learning algorithm is presented. The Q-learning algorithm is used to learn the weights of issues, and the Bayesian learning algorithm is used to learn the reservation price of issues. Experiments show that the algorithm can help agents to negotiate more efficiently.

Research of Extracting Data from HTML Web Pages Automatically

WANG Ru, SONG Han-tao, LU Yu-chang

2003, 12(S1): 104-108.

[Abstract](183)

Abstract:
In order to use data information in the Internet, it is necessary to extract data from web pages. An HTT tree model representing HTML pages is presented. Based on the HTT model, a wrapper generation algorithm AGW is proposed. The AGW algorithm utilizes comparing and correcting technique to generate the wrapper with the native characteristic of the HTT tree structure. The AGW algorithm can not only generate the wrapper automatically, but also rebuild the data schema easily and reduce the complexity of the computing.

Decrease of RMI Application Coupling Degree Based on Dynamic Proxy and Interceptor

YAN Bo, ZHAN Shou-yi, ZHANG Yan

2003, 12(S1): 109-113.

[Abstract](160)

Abstract:
Based on Java RMI framework, a new design is introduced to plug common services into RMI application without modifying the remote interface. This design improves the mechanism of RMI, which is based on dynamic proxy and interceptor technology. The implementation of class loader and stub is custom. The design ensures both the integrity of RMI mechanism and the plug-ins of some common services that are based on component. The design improves the modularization of application and decreases the coupling degree among different modules; by this means these middle-ware's modules gain more scalability and flexibility.

Adaptive DirectShow Framework for Layered MPEG-4 Video Multicast

GAO Yu-jin, SHI Feng, ZHANG Yan-su

2003, 12(S1): 114-119.

[Abstract](81)

Abstract:
An extensible framework was proposed to implement the hierarchical and adaptive control and feedback mechanism of layered MPEG-4 video multicast transmission in DirectShow architecture. In our framework, layers of MPEG-4 video and FEC data are wrapped dynamically in RTP packets to pass through the heterogeneous network effectively. An adaptive control center is designed to control the actions of the related components dynamically according to varying resources availability on local host and network. This effective and adaptive framework can be used to instruct the implementation of applications based on layered MPEG-4 video multicast transmission and other designs of multimedia application frameworks.

Hybrid Chinese Information Retrieval Model Based on the Combination of Keyword and Concept

FAN Xiao-zhong, LI Hong-qiao, LI Liang-fu

2003, 12(S1): 120-123.

[Abstract](167)

Abstract:
A hybrid model that is based on the Combination of keywords and concept was put forward. The hybrid model is built on vector space model and probabilistic reasoning network. It not only can exert the advantages of keywords retrieval and concept retrieval but also can compensate for their shortcomings. Their parameters can be adjusted according to different usage in order to accept the best information retrieval result, and it has been proved by our experiments.

Verilog-VHDL Simulation Interoperability

HU Yan-xiang, LIU Ming-ye

2003, 12(S1): 124-128.

[Abstract](138)

Abstract:
A Verilog-VHDL translating method directed by simulation semantics is presented. Based on the analysis and comparison, three steps are taken to implement the translation. Through semantic analyzing and syntax tree reconstructing before translation, the main part of Verilog is supported. According to the level in the design hierarchy, the modules are translated in down-top order, and that results in a correct VHDL declaration-reference order. The translation rules of assignment statements and delay/timing constructs are also explained in detail. This method has been successfully implemented in the translator developed by the authors. The correctness has been validated by many examples.

Scalable Compression Algorithm for Video Monitoring System

WANG Yi-zhuo, SHI Feng

2003, 12(S1): 129-133.

[Abstract](147)

Abstract:
A layered compression algorithm is presented which delivers spatial scalable encoded bit streams for remote video monitoring system. The complexity of the algorithm is modest and is well suited to real time implementation. Based on the layered compression algorithm, a codec system model is established. High-speed video compression can be realized with parallel data compression in this codec system. For image reconstruction, a prediction method using two nearest pix points is presented.

Automatic Video Segmentation Algorithm by Background Model and Color Clustering

SHA Yun, WANG Jun, LIU Yu-shu

2003, 12(S1): 134-138.

[Abstract](168)

Abstract:
In order to detect the object in video efficiently, an automatic and real time video segmentation algorithm based on background model and color clustering is proposed. This algorithm consists of four phases: background restoration, moving objects extract, moving objects region clustering and post processing. The threshold of the background restoration is not given in advanced. It can be gotten automatically. And a new object region cluster algorithm based on background model and color clustering to remove significance noise is proposed. An efficient method of eliminating shadow is also used. This approach was compared with other methods on pixel error ratio. The experiment result indicates the algorithm is correct and efficient.

Ontology Learning for Chinese Documents Based on SVD and Conceptual Clustering

LI Shou-Li, LIAO Le-Jian, CAO Yuan-Da, CAO Shu-Gui

2003, 12(S1): 139-144.

[Abstract](236)

Abstract:
In order to construct Chinese ontology easily, an automated ontology learning technology for Chinese documents based on singular value decomposition (SVD) and conceptual clustering is proposed . First the system extracts concepts from a set of domain-specific documents by using SVD technology, and then acquires subsumption relationships between the concepts by means of hierarchical conceptual clustering method. The system thus yields domain-related concept hierarchy.

2003 Vol. 12, No. S1