JOURNAL OF BEIJING INSTITUTE OF TECHNOLOGY

Bark-Band Residual Noise Model for Parametric Audio Coding

WANG Jing, JIN Yan-wei, ZHAO Sheng-hui, KUANG Jing-ming

2004, 13(S1): 1-6.

[Abstract](201)

Abstract:
A Bark-band residual noise model integrated with the human hearing mechanism is proposed to efficiently complement sinusoidal model in parametric audio coding. The time-varying spectrum of the residual noise is retrieved by Bark-scale piecewise constant magnitude estimates along with random phases. In the proposed noise model, Bark bands information is obtained by short-time FFT method and window overlap-add technique is exploited to remove boundary discontinuities. SVQ is also incorporated into parameter quantization process for the low bit-rate coding demand. Simulation results and informal listening tests show that when the sinusoidal model is combined with the Bark-band noise model, better synthesis audio quality can be achieved compared with the original sinusoidal modeling audio codec.

Reliability Evaluation of Mobile Communication Networks

REN Xiao-tao, ZHAO Sheng-hui, KUANG Jing-ming

2004, 13(S1): 7-11.

[Abstract](155)

Abstract:
A new reliability evaluation measure, global clustering reliability (GCR), is proposed. Firstly, the common measures used in invulnerability and survivability evaluation of mobile communication networks are discussed, and the shortcomings of these measures are pointed out. Then a new reliability evaluation measure, GCR, which is applicable to mobile communication networks, is proposed. And some properties and theorem about this measure are put forward. Finally, simulation calculation of reliability evaluation that uses this measure to 12 kinds of topological networks is accomplished. And the comparison between this measure and link connected factor (LCF) measure is also given. The results proved that the design of GCR is reasonable, its computation is rapid, moreover, it can take into account of invalidation of both nodes and links, and it has good physical meanings

Improvement of Channel Estimation with 16QAM Modulation over Fading Channel for DS-CDMA

YANG Yu, KUANG Jing-ming

2004, 13(S1): 12-16.

[Abstract](175)

Abstract:
The application of low complexity and low order robust regression algorithm in channel estimation with 16QAM over fading channel for DS-CDMA is presented in this paper After initial channel estimation with classical methods, channel gains estimated are filtered by linear or conic regression algorithm within a given regression length Simulation results show that this method offers up to 0,3 dB gain in a DS-CDMA system. The length and order of regression algorithm are two key parameters, which affect the system performance significantly and the optimal values of which depend on the speed of mobile station. It is demonstrated that this improved method can track fading channel accurately and outperforms over classical methods substantially by selecting appropriate parameters of regression algorithm under a certain channel environment.

Feature Extraction of Radar Range Profiles Based on Normalized Central Moments

FU Xiong-jun, GAO Mei-guo

2004, 13(S1): 17-20.

[Abstract](181)

Abstract:
The normalized central moments are widely used in pattern recognition because of scale and translation invariance. The moduli of normalized central moments of the 1-dimensional complex range profiles are used here as feature vector for radar target recognition. The common feature extraction method for high resolution range profile obtained by using Fourier-modified direct Mellin transform is inefficient and unsatisfactory in recognition rate And. generally speaking, the automatic target recognition method based on inverse synthetic aperture radar 2-dimensional imaging is not competent for real time object identification task because it needs complicated motion compensation which is sometimes too difficult to carry out. While the method applied here is competent for real-time recognition because of its computational efficiency. The result of processing experimental data indicates that this method is good at recognition.

The Neural Network Model of Sinusoid Activation Transfer Function

LIU Yu, WANG Qing-lin

2004, 13(S1): 21-25.

[Abstract](175)

Abstract:
A new type of neural network is described, which is basing on Fourier series, and the activation transfer function in its neuron model is sinusoid, ft can approximate to any function, which is continuum in every segment, with any precision with by layers only. We also provide the computer approach emulation results of different kinds of static function.

LQ Speed Control of Pump Controlled Motor System

GUO Chu-sheng, WANG Xiang-zhou, WANG Yu

2004, 13(S1): 26-30.

[Abstract](154)

Abstract:
A linear quadric (LQ) optimal speed control algorithm is proposed for the speed control of a pump controlled motor hydraulic system. The control theme consists of optimal state feedback and disturbing compensation based on observation. The optimal state feedback bases on LQ cost function. The disturbing compensation is realized through reconstructing the state of load torque. A series of simulation are performed, and the results show that the control performance is satisfactory and can be maintained under changes of load torque.

Sensor Registration Based on Neural Network in Data Fusion

DOU Li-hua, ZHANG Miao

2004, 13(S1): 31-35.

[Abstract](151)

Abstract:
The contents of sensor registration in the multi-sensor data fusion system are introduced, and some existing methods are analyzed. Then, one approach to sensor registration based on BP neural network is proposed. Here the measurements from radar are transformed from the polar coordinate system to the Cartesian coordinate through a BP neural network. With this approach, the systematic errors are removed as well as the coordinate is transformed. The efficiency of this method is demonstrated by simulation, and the result show that this approach could remove the systematic errors effectively and the DAR are closer to real position than DBR.

Resource Schedule in Grid Based on Market Models

WANG Da-zhen, ZHU Lie-huang, SONG Han-tao

2004, 13(S1): 36-40.

[Abstract](171)

Abstract:
A new modern resource management method based on economic model is proposed. Giving mathematic description about economic model; analysis different resource scheduling methods based on deadline and budget constrained which present by Buyya, point out shortcoming of Buyya's schedule method. Considerate integrate factor of time and budget, by import a weight coefficient named a , puts forward a new resource schedule method named STPP based on economic models of Buyya. Contrast to old schedule strategy of Buyya through analysis and experiments, STPP policy is more flexible, and is easy to import other new QoS parameters.

Adiabatic Decomposition of Two Kinds of Organic Peroxides by Accelerating Rate Calorimeter

QIAN Xin-ming, LIU Ping, LIU Li

2004, 13(S1): 41-44.

[Abstract](166)

Abstract:
The accelerating rate calorimeter was applied to study the thermal hazard of two kinds of organic peroxides, i.e. methyl ethyl ketone peroxide (MEKPO) and benzoyl peroxide (BPO). And their thermal decomposition characteristics were discussed. Meanwhile, thermal decomposition characteristics of MEKPO and BPO vvere compared. The result indicated that MEKPO is more sensitive to thermal effect than BPO. While once the thermal decomposition takes place. BPO will be more hazardous than MEKPO due to its serious pressure effect. Thermal kinetic analysis of these two kinds of organic peroxides was also taken, and the kinetic parameters for them were calculated. The study of thermal decomposition of MEKPO solution with different initial concentrations indicated that, the lower concentration MEKPO solution is, the higher onset temperature will be. And with the addition of organic solvent, it becomes more difficult for MEKPO to reach a thermal decomposition. Therefore, its thermal hazard is reduced.

Interference of the Cloud to Capacitance Proximity Fuze

LI Ming, CUI Zhan-zhong, ZHANG Wan-jun

2004, 13(S1): 45-48.

[Abstract](190)

Abstract:
Based on the study of the characteristics of the cloud, firstly the interference mechanism of the capacitance proximity fuze passing through the cloud has been studied. Analysis shows that the medium property of the cloud only, has little effect on the capacitance proximity fuze. Secondly, the adherence interference of the cloud to capacitance proximity fuze has been studied for the first time in this paper. Then finite element analysis (FEA) method has been used to simulate the adherence interference of the cloud. Simulation result shows that the cloud adherence effect interferes the output of the capacitance fuze greatly. At last, experiments have been made for the study of the cloud interference.

Investigation and Application of Automatic Fingerprint Identification Based on Fuzzy Pattern Recognition

YANG Yang, KANG Jing-li, GUO Yin-jing, TANG Fu-hua

2004, 13(S1): 49-53.

[Abstract](155)

Abstract:
Fingerprint image is a typical non-restraint image that has some uncertainty, which makes it difficult to perform identification using classical approach. Therefore, fuzzy pattern recognition is applied to match individual query by searching the entire template database. The fuzzy maximum subordinate principle is used to solve shift matching. Through experimenting and analyzing, the approximate principle fuzzy method is employed by selecting fuzzy characteristics and determining the similarity function to achieve the further accuracy. Theoretical and experimental results show this approach is effective and reasonable.

Numerical Simulations of Jet Flow Inside Launching Box and Design of Pressure Opening the Covers of Missile Launching Box

LIU Qi, HAO Ji-guang, JIANG Yi, CHEN Jian-wei

2004, 13(S1): 54-57.

[Abstract](161)

Abstract:
Numerical simulations are presented for jet flow inside a launching box. The predictions are based on solutions of the unsteady three-dimensional Reynolds-averaged Navier-stokes equations. Since the pressure opening the forward cover is given, the pressure opening the backward cover is designed by analyzing the flow field inside the launching box. The κ -ε turbulent model is presented and the structured meshes are used through the whole computational field.

RCS Reduction of Airborne Dispenser

HAO Lu, WU Jia-sheng

2004, 13(S1): 58-62.

[Abstract](161)

Abstract:
The radar cross section (RCS) of dispenser and its components is computed by graphical electromagnetic computing (GRECO) method, which bases on physical optics (PO) method. A satisfied agreement is gotten between computed and measured results outdoor. The results show that the main scattering source of the dispenser is the mirror reflecting of the body; in the most crucial nose-on region, the nose mirror reflecting plays important role; the corner reflecting is important to the fins' RCS. The corresponding measures to reduce dispenser's RCS are proposed. It is indicated that to reduce RCS, shaping should be adopts first, while aerodynamic characteristics and stealth characteristics should be considered synthetically during the design of dispenser.

Design of Robust-Adaptive Controller of Extended Range Guided Munition

WANG Jin-zhu, LIU Zao-zhen

2004, 13(S1): 63-67.

[Abstract](161)

Abstract:
Extended range guided munition (ERGM) is a complicated multi-input and multi-output control system. It is very difficult for general control method to meet both the designing stability and its dynamical performance, for the parameters being uncertain in the ERGM model. Adaptive controller and robust tracking controllers are presented respectively in this paper. These two approaches are synthesized in order to design an improved and applied performance of ERGM controller. Computer simulation technology is used to validate it, and the result shows the design is reasonable and applied.

Global Control Simulation of Electric Vehicle Based on Finite State Machine Theory

ZOU Yuan, SUN Feng-chun, HE Hong-wen

2004, 13(S1): 68-72.

[Abstract](153)

Abstract:
Finite state machine theory (FSM) is introduced and applied to global control of electric vehicle. Theoretical adaptation for application of FSM in control of electric vehicle is analyzed. Global control logic for parts of electric vehicle is analyzed and built based on FSM. Using Matlab/Simulink, BJD6100-HEV global control algorithm is modeled and prove validity by simulation.

Equalization Charging and Protection System for Electric Vehicle

LI Hong-lin, SUN Feng-chun, ZHANG Cheng-ning, SHAO Gui-xin

2004, 13(S1): 73-77.

[Abstract](189)

Abstract:
A system is developed to improve the series battery packs uniformities and charging protection and the implementation of battery equalization charging and protection system is also introduced. The functions of equalization charging and overcharging protection are analyzed and the control model of series battery packs equalization charging is setup. The diverting-current and feedback bus voltage are measured during the series Li-ion battery packs equalization charging experiment. The field operation on Electric luxury transit bus BFC6100EV shows that the system betters the battery series charging uniformities and overcharging protection, improves the battery performance and extends the battery life.

Theory of Vehicle's Durability Correlation Test

WANG Guo-jun, YAN Qing-dong, GAO Feng, CHEN Xin, WANG Bao-min

2004, 13(S1): 78-81.

[Abstract](184)

Abstract:
The theory of vehicle's correlation tests was discussed and the correlation test mathematical model was created. According to the damage theory, the correlation equation was brought up. The method to solove it was given. The text gives the theory basis of vehicle's correlation tests. The results can be used to give the vehicle's test designation and to make the test to fit the actual environments. Besides that, the methods give acceleration and strengthen effects.

Simulation of Steering Performance for Electric Drive Tracked Vehicle

SUN Feng-chun, LU Lian-jun, GU Zhong-li

2004, 13(S1): 82-87.

[Abstract](161)

Abstract:
According to the analysis of the fundamental steering theories of the electric drive tracked vehicle, a new effective electric drive tracked vehicle model is built in this paper. And the simulation of the steering performance of the vehicle is made. The results show that the electric transmission has great advantage on the steering performance aspect; the small radius steering and even the pivot steering is realizable, and the agility and the rapidness is wonderful. The regenerative energy can be fully utilized by controlling.

New Approach to the Synthesis of Benzhydryl 6α-Bromopenicillanic Acid -1-Oxide

XU Wei-liang, LI Yun-zheng, ZHANG Qing-shan, ZHU He-sun

2004, 13(S1): 88-91.

[Abstract](185)

Abstract:
The synthesis of Benzhydryl 6a-Bromopenicillanic acid -1-oxide with air catalyzed by Fe(NO3)3-FeBr3 using Benzhydryl 6a-Bromopenicillanic acid as starting material was reported. The oxidation was selective and no sulfone was formed. Compared with conventional method, using the Fe(NO3)3-FeBr3 as catalyst, the reaction time was reduced from 4 h to 1 h and the yield was enhanced from 65.0% to 93.5%.

Synthesis of 2-Substituted Benzimidazol-N-biphenyl Acid and Crystal Structure of 4'-[(2-n-Propyl-1H-benzimidazol-1-yl)methyl] Biphenyl-2-carboxylate Acid

YU Wei-fa, ZHOU Zhi-ming, ZHAO Xin-qi, YU Cong-xuan

2004, 13(S1): 92-97.

[Abstract](128)

Abstract:
Nine analogues of telmisartan, 2-substituted benzimidazol-N-biphenyl acid, were designed and synthesized, from substituted benzimidazoles reacted with methyl 4'-(bromomethyl)- -biphenyl-2-carboxylate, then hydrolysis with KOH in MeOH and H2O. Their structures were confirmed by IR, 'H NMR, MS spectroscopy and elemental analysis. The crystal structure of 4'-[(2-n-propyl-1H-benzimidazol-lyl) methyl] biphenyl-2-carboxylic acid was determined by single crystal X-ray diffraction.

New Cell Viability Measurement of SH-SY5Y Cells in the PD Research-Alamarblue^TM

DENG Yu-lin, NIU Li-yuan

2004, 13(S1): 98-103.

[Abstract](187)

Abstract:
The traditional MTT assay requires destructive analyses and is not convenient in continuous monitory of cell viability. However, a new cell model was developed in this research, by using the oxidation-reduction (redox) indicator alamarblue? instead of the MTT assay. The alamarblue?does no harm to cells and provide a much more safe and convenient methods of measurement. Firstly, cell apoptosis was induced by different concentration of 6-OHDA, then the cell viability was tested by the alamarblue?at a serial of time points. Finally, the optimism cells density, 6-OHDA concentration and testing time point were gained to set a wonderful SH-SY5Y cell model in our research. And when it is applied in the study of neuroprotection effects of NAC, GSH and Catalase, the new model reveals undeniable advantages.

A Class of a Second-Order Two-Point Boundary Value Problem on a Measure Chain

DU Zeng-ji, GE Wei-gao

2004, 13(S1): 104-107.

[Abstract](172)

Abstract:
A class of second-order two-point boundary value problem on a measure chain was considered. Under some suitable conditions, by using the Leggett-Williams fixed point theorem in an appropriate cone, the existence of at least three positive solutions to this nonlinear problem was obtained.

Energies and Transition Rates for the Doubly-Excited States of Be-Like Ar¹⁴⁺Ion

GOU Bing-cong, LIU Yi-dong, WU Xiao-li

2004, 13(S1): 108-111.

[Abstract](182)

Abstract:
The energies, radiative and Auger rates of the doubly excited states of Be-like Ar14+ ion are studied using the multi-configuration-interaction method and the model potential method. The doubly excited states of Be-like Ar14+, He-like S14+ and Ar16+ ions are labeled by the quantum numbers K. T and A to show the systematic regularity. The results show that the spectroscopy of these states of Be-like ions is different from that of He-like ions because of the polarization and core penetration effects from the 1s2 core electrons.

DFT Study of Electron Affinities of o-, m-,p-Halobenzyl Radicals

GAO Ai-fang, XU Wen-guo, LI Qian-shu

2004, 13(S1): 112-116.

[Abstract](179)

Abstract:
The electron affinities of the isomer XC6H4CH2/ XC6H4CH2- (X=F, Cl, Br) species have been determined using seven density functional theory (DFT) methods. The basis set used in this work is of double-ζ plus polarization quality with additional diffuse s- and p-type functions, denoted DZP++. Three different types of the neutral-anion energy separations reported in this work are the adiabatic electron affinity (EAad), the vertical electron affinity (EAvert), and the vertical detachment energy (VDE). The most reliable adiabatic electron affinities are obtained at the DZP++ BPW91, BP86, and B3LYP level of theory. The BPW91 methods are the closest to the experiment values; The BHLYP method predicts the smallest EAad and B3P86 method predicts the largest EAad, which are the worst reliable methods. In addition, for a given halogen substituent, the meta isomer has the largest electron affinity and the para isomer has the smallest.

Fingerprints Matching Based on the Integrated Template

LU Xiang-jiang, WANG Chong-wen, LIANG Yun-rong, ZHANG Lei

2004, 13(S1): 117-120.

[Abstract](146)

Abstract:
Traditional fingerprints matching approaches are based on the minutiae and the texture characteristics. It is difficult for today's techniques to deal with the images captured by the solid-state fingerprint sensors because the sampling area of these sensors is very small and only portion of the fingerprint can be obtained. In this paper, a novel integrated template has been built using several images and combining the minutiae with the texture characteristics at the same time. By using a kind of Gabor filters (eight directions) on the region around the reliable minutiae, local texture of each minutia termed as minutiacode is extracted. Further, a real-time matching algorithm using the integrated template is presented. The output is determined by the weight factor of the compound matching. Finally, experimental results show that this system performs well in reducing false reject rate (FRR).

2004 Vol. 13, No. S1