2000 Vol. 26, No. 5

Display Method:
Surface Modification of Metals Irradiated by Intense Nanosecond Pulsed Electron Beam
HAN Li-jun, A She-er, JIANG Xing-liu, KANG Wen
2000, 26(5): 497-500.
Abstract:
Under irradiation of intense-nanosecond-electron beam with power density of 109 W/cm2,tensnanosecond duration,the metal surfaces with enhancement of hardness, corrosion resistance and other physico chemical behavior improvement have been obtained due to the microstructure changing. Thermal transfer ...
Microstructures of Multi-phase Materials In-situ Formed in γ-TiAl Based Alloys
LI Jian-guo, ZHANG Fu-xiang, WANG Li-jun, ZHANG Yong-gang
2000, 26(5): 501-504.
Abstract:
The phases and microstructures in-situ formed by solid-state reaction were studied after the elements of B, C and Si were single and mixed doped to the TiAl-based alloys. The results showed that, in the Ti-Al-B alloys, the phases of TiAl, Ti3Al, and TiB2 were formed; in the Ti-Al-Si alloys, the ph...
Numerical Analysis of Circular Aperture Antennas on Finite Planes
GAO Wen-jun, Lü Shan-wei
2000, 26(5): 505-508.
Abstract:
The circular aperture antenna which is an open-ended circular waveguide stimulated by TE11 mode is analyzed. The method of moments is employed in conjunction with the equivalent-source technique and the modal expansion theory to analyze the open-ended circular waveguide. No restriction is imposed on...
Decoupling Sliding Mode Control in A Nonlinear Spacecraft System
ZHU Min-xiong, SONG Yi, SONG Chao-qing
2000, 26(5): 509-512.
Abstract:
A control method with sliding mode of nonlinear spacecraft system is provided in this paper, in which the interactive influences among channels of strong nonlinear spacecraft system are decoupled. The decoupled spacecraft with large parameter variations and external disturbances is of good robustnes...
Design Method of Fuzzy System to Control Large Maneuver Flight of Aircraft
WANG Pi-hong, GAO Jin-yuan, YANG Ke-ming
2000, 26(5): 513-515.
Abstract:
There is strong nonlinear in the model of an aircraft because flight parameters may change violently in the case of large maneuver flight within the full flight envelope. The traditional PI controller can not guarantee the good control performance within the full flight envelope. A new kind of fuzzy...
Application of  H Filtering to Fast Ground Alignment of Inertial Navigation Systems
WANG Yan-dong, FAN Yue-zu
2000, 26(5): 516-518.
Abstract:
The approach of H filtering is presented, which is applied to alignment of inertial navigation systems. The error model of INS(Inertial Navigation System) is introduced,and the observability of the INS error model is analyzed. H filter is designed to an observable subsystem. The simulation results...
New Method of Small Sample Experiment for the Simulation System with Hardware in the Loop for Homing Missile
WANG Xiao-hu, ZHANG Ming-lian, DU Yi-min, YANG Xin
2000, 26(5): 519-522.
Abstract:
The small sample experiment method of a simulation system with hardware-in-the-loop(HWIL) for radar homing missile is studied due to radar guider's high expenses, and a new method of small sample experiment is proposed based on the sensitivity of the target maneuver to the undershoot errors and mane...
Improvement on the Theoretical Model for Dissipation-rate Budgets in Near-wall Region of a Turbulent Boundary Layer
LU Li-peng, MIAO Ze-chun, CHEN Mao-zhang
2000, 26(5): 523-526.
Abstract:
A symmetric resonant-triad theoretical model is proposed for the turbulent coherent structures in near-wall region of a turbulent boundary layer,sothe terms of triple-correlation can be analyzed theoretically. In accordance with the new theoretical model, budgets of the dissipation-rate of turbulent...
Experimental Study of the Dynamic Responses of the ECS-s Bleed System
ZHAO Jing-quan, LIN Gui-ping, YUAN Xiu-gan
2000, 26(5): 527-529.
Abstract:
The experimental results are reported about the pressure transient responses and temperature transient responses of the bleed system of an aircraft environmental control system when the bleed air flows, pressure and temperature are varied. Results show that the pressure response of the bleed system ...
Analysis of the Accuracy of the Spatial Discretization Schemes for Surface Integrals in Finite Volume Method
MA Liang, LI Ting-he
2000, 26(5): 530-534.
Abstract:
The order of accuracy of Vertex-Centered finite volume scheme for the unsteady Euler equations is investigated and compared with that of cell-centered and cell-vertex schemes. An error analysis using Taylor series expansion is applied. It shows that the accuracy of the vertex-centered scheme, simila...
Tracing Post-buckling Path of Structures by Interval Newton Method
TONG Zong-kai, WANG Shou-mei, QIU Zhi-ping
2000, 26(5): 535-538.
Abstract:
Post-buckling analysis was traditionally conducted by arc length method. In view of the feature of global convergence of the interval iteration method in solving nonlinear equation sets, an approach is proposed to apply this method in tracing post-buckling path of structures. An incremental solution...
Unit Cell Geometric Model of 4-Step 3-D Braided Composites
CHEN Zuo-rong, ZHU De-chao, LU Meng
2000, 26(5): 539-542.
Abstract:
After briefly reviewing the proceeding of geometric model of 4-step 3-D (1×1) rectangular braided composites, yarn path in 4-step rectangular braiding process is analyzed. On this basis, a 3-D solid unit cell geometric model is proposed, the characteristics of geometry of 3-D braided composites are ...
Perfect Interface Based Method for Homogenization
CHEN Zuo-rong, ZHU De-chao, LU Meng
2000, 26(5): 543-546.
Abstract:
Several representative micro-mechanical models for the analysis of the effective elastic properties of unidirectional fiber-reinforced composites and textile composites are briefly reviewed, and their characteristics are pointed out. In view of the limitations of the classical mechanical models for ...
Changing Tendency of Dimensions of Mixed Type Plane Pilots and Its Human Engineering Significance
WANG Xing-wei, YUAN Xiu-gan, SUN Ming-zhao, WANG Rong-di, PENG Fu-min
2000, 26(5): 547-551.
Abstract:
In order to study the changing extent and tendency of the pilot dimensions of different times/districts/plane-types,5~13 dimension values were obtained by measuring 656 pilots, and those of the 70s' were as controls, difference between the data of different districts/plane-types was analyzed. It was...
Experimental Investigation on Porous Plate Water Sublimator under Constant Heat Flux
WU Zhi-qiang, YUAN Xiu-gan, SHEN Li-ping, HAN Li-jun, LI Tan-qiu
2000, 26(5): 552-555.
Abstract:
Water sublimator is main heat sink of portable life support system of extravehicular activity (EVA) space suit. Manufacture techniques of porous plates are developed. Breadboard and tester of water sublimator are designed. An experimental study under constant heat flux is carried out on water sublim...
Stochastic Crack Growth Approach under Corrosive Environment for Durability Analysis
ZHANG Jian-yu, LIU Ai-min, FEI Bin-jun
2000, 26(5): 556-560.
Abstract:
In order to analyze the aircraft structural reliability under corrosive environment, stochastic crack growth approach (Cor-SCGA) for durability analysis is established. Assuming the influence of the pre-corrosion in parkand the influence of corrosion in flight are independent, the fatigue quality of...
Optimization of Aircraft Structural Economic Maintenance Programme
LIU Xiao-dong, LIU Wen
2000, 26(5): 561-564.
Abstract:
The aircraft structural economic maintenance is one of the important aspects in the durability design of advanced aircraft.To assure economic life and reliability of aircraft structure,an economic maintenance program is essentially needed.In this paper,the effect of various factors on the determinat...
Study of the Heat Transfer Characteristics of PhaseofChange Thermal Storage/Radiation Heat Sink
ZHAO Chao-yi, YUAN Xiu-gan, SUN Jin-biao, LI Tan-qiu
2000, 26(5): 565-568.
Abstract:
Performance studies of a phase change thermal storage/radiation heat sink for extravehicular activity have been undertaken by experimental investigation and numerical simulation. The test specimens of phase change thermal storage were designed and the cooling tests of phase change thermal storage we...
Stability and Precision Analysis for Precise Integration Method
ZHAO Li-bin, ZHANG Jian-yu, WANG Shou-mei
2000, 26(5): 569-572.
Abstract:
The precise integration method, one of the direct integration methods for problems in structural dynamics, was analyzed. Several comments were made regarding to its formulation, numerical stability, computational accuracy and cost. The method is conditionally stable and belongs to the category of ex...
Study on Electromagnetic Scattering Characteristics for Complex Target Using Shooting and Bouncing Rays
LI Jun, MA Dong-li, WU Zhe
2000, 26(5): 573-576.
Abstract:
The accurate mathematical externality of the target was established with surface generation method in computer graphics, which was dispersed into triangular facets. Relationships between the geometrical elements were described with topological structure. The method of shooting and bouncing rays was ...
Exact Solution of Eigenvalue and Eigenvector Derivatives and Its Application in Structural Dynamics
LI Shu, ANG Xiao-gu
2000, 26(5): 577-580.
Abstract:
To compute eigenvector derivatives with repeated eigenvalues, several extended Nelson's methods have been developed. Some of these methods have been pointed out that they may fail in some cases. To deal with those difficulties under repeated eigenvalues circumstances, we develop formulas to calculat...
Study of Active Nucleation Site Density in Subcooled Nucleate Pool Boiling
WU Yu-ting, YUAN Xiu-gang, YANG Chun-xin, MA Chong-fan
2000, 26(5): 581-583.
Abstract:
The active nucleation site density is an important parameter of nucleate boiling heat transfer model, but none of those theoretical models made by far has successfully predicted the active site density. A fractal model has recently been proposed by authors to describe the active site density in nucl...
Mechanical Performances of Piezoelectric Element and Optimal Control
REN Xiu-hua, DING Hua, MAI Han-chao, LU Meng
2000, 26(5): 584-587.
Abstract:
On the basis of performances of the piezoelectric actuators and sensors,the characteristics of beam with highly distributed piezoelectric sensors and actuators and a feedback conditioning system are analyzed,and the dynamic differential equation is also derived.A finite element model of the intellig...
Upwind Scheme Used on Two Dimensional Unstructured Adaptive Meshes
WANG Ping, ZHU Zi-qiang, Lü Xiao-bin
2000, 26(5): 588-591.
Abstract:
The AUSM+ (Advection Upstream Splitting Method) finite-volume scheme, which was developed in structured grids, has been extended to be used on unstructured meshes. The linear reconstruction approach using Green-Gauss gradient estimation is applied in order to obtain second order spatial accuracy. A ...
Flow Characteristics and Its Melioration of Swept Wing/Body Interference
ZHANG Hua, Lü Zhi-yong
2000, 26(5): 592-595.
Abstract:
A flow visualization and pressure distribution measurement test have been performed to understand the flow characteristics of swept wing/body junctions better. Different small strakes have been used to ameliorate the characteristics. The results show that with the increase of the angle of attack and...
Simple Conjugation-Gradient BP Algorithm for Feedforward Neural Networks
LIANG Jiu-zhen, HE Xin-gui, HUANG De-shuang
2000, 26(5): 596-599.
Abstract:
The high dimension of the learning error function for BP networks and the difficult computation complexity are incestigated. A simple modified conjugation-gradient decent algorithm (MPARTAN) is proposed based on improving the gradient BP algorithm. That the computation complexity of this algorithm i...
Certificate System in Secure Distributed Application Frame
LU Yu, JIN Hui-hua
2000, 26(5): 600-603.
Abstract:
According to the characteristics of distributed certification system, a secure distributed application framework based on client/server computation model is put forward, Which exposes how to combine the distributed certification system into it and to afford security mechanism such as authentication ...
Process Modeling of Design of Mechanical Product
HAN Xiao-jian, DENG Jia
2000, 26(5): 604-607.
Abstract:
Product design is a complicated thinking activity of creation of human.Based on analyzing product design and its process,using a theory and method of aggregating and mapping,models of product design,process of product design ,process of conceptual design of product were constructed,a frame of networ...
Existence of Duck Solutions of A Kind of Differential Equations with Small Parameter
LI Cui-ping
2000, 26(5): 608-611.
Abstract:
A kind of one parameter planar singular perturbation equation is studied by the qualitative theory of ordinary differential equations,asymptotic analysis methods,implicit function theorem and fixed point methods.Some sufficient conditions are given to support the existence of duck solutions and duck...
Matrix Coding in GA and Its Application to Fuzzy Modelling
DAI Ji-yang, MAO Jian-qin, ZHANG Jian-gang
2000, 26(5): 612-615.
Abstract:
In the practical applications of genetic algorithm(GA), a lot of problems can be described as tree structures. In fuzzy modelling, the structure identification of a fuzzy model is to partition the input domain, which is in essence a process of complicated nonlinear optimization. The partition of the...
Study on Flight Management and Control System for Uninhabited Combat Aerial Vehicles
QIU Xiao, LIAO Fang
2000, 26(5): 616-620.
Abstract:
The development status of uninhabited combat aerial vehicles(UCAVs) in the world is introduced and evaluated. The requirements and characteristics of the flight management and control system (FMCS) for UCAVs are discussed. The layer constructures of the UCAV FMCS are analyzed with the layer theory o...