Abstract:This paper presents the result of an experimental study on the flowrate characteristics of coaxial swirling injector and coaxial unswirling injector. Effects of the interaction between gas and liquid flows in injector and the change of environmental pressure on the flowrate characteristics of injectors are investigated. The results show that the effect of the interaction between gas and liquid flows is much more significant for coaxial swirling injector than that for coaxial unswirling injector, and that increasing environmental pressure results in the same effects on the gas flowrate characteristics, but effects on the liquid flowrate characteristics for these two type injectors are different.

Abstract:Based on the theory of strip distributed transfer function method (SDTFM), a new element, called generalized super-element (GSE) is given for 2-D problems and its stiffness matrix and nodal force vector are derived. With the use of generalized super-element, the application of SDTFM is extended to the 2-D problems of arbitary geometrical boundary.

Abstract:Attacking the mobile missile base is considered and an aiming-point-choosing model for striking its sector mobile region is presented. The model is realized and the result is analyzed. The model has generality for attacking mobile target and is also useful for making an operational decision.

Abstract:SPP algorithm is developed for the solution of tridiagonal and block tridiagonal equations. In the solution of the tridiagonal system, file I/O and result transfers are time consuming. SPP algorithm has taken the characteristic into account. The overlapping of computation, file I/O and communication is fully exploited. The computation count and communication count are analysed. The algorithm is tested on NOWs. It shows that SPP algorithm is suitable for distributed computing.

Abstract:The number of operations of the algorithm for measurement element selection is very large. The paper deals with this question. And its parallel algorithm is presented, with regard to the fusion method in reference [1]. The scalability for the algorithm is analyzed. The predicted speed-ups are given.

Abstract:This paper presents an approximate method of flexible multibody system lumped parameter model combined finite element with numerical integration. Based on Lagrange's method, the flexible multibody dynamics model of rooted topological tree is built.

Abstract:End-point acceleration feedback is a kind of simple and efficient method for vibration suppression of flexible manipulator, but until now the mechanism of vibration suppression and stability is not very clear. The paper has made a thorough and systematic analysis of the built-in mechanism and proved its feedback stability. Some correct and guiding conclusions have been drawn, and also verified experimentally.

Abstract:This paper studies the problem of H_∞filtering for discrete-time systems with time delay. The sufficient conditions for the existence of H_∞ filter are derived in terms of a Modified Discrete Algebraic Riccati Inequality(MDARI ). Moreover the design method of H_∞ filter is obtained based on a MDARI, which may be solved by a recursive algorithm.

Abstract:In the paper we present the initiative radar guilder modeling which adopts the proportion guiding method using the “control-oriented”model's linear frequency algorithm. The algorithm can identify the plant's model and the hard bound of model's error. Since the guilder's working environment is bad and its relationship with the target and environment is very complicated, we make use of the tuned linear frequency algorithm. The simulating result shows that this method has a good robust and reliability.

Abstract:The interactive system is one of the most important parts in the integrated environment of modeling and simulation. It mainly resolves the relationship between the human and the computer of simulation (CS), and it makes it convenient for the users to communicate with the CS at high speed. It can supervise the running of simulation in real-time. We briefly introduce the system environment at first; several aspects, for instance, designing the system as a whole, analyzing and processing the interactive commands, realizing the functions, are discussed in this paper. Moreover, we introduce something about the user interface.

Abstract:Phased missions system involves several mission phases (or stages). The stage-modulars will be relative to each other, and can not be treated independently as usual. This paper studied this problem, proposed some typical time-varing structures for phased missions system with relative stage-modulars. Using these basic structures, we can model phased missions system and compute its mission reliability exactly. The results have been used successfully.

Abstract:The general expression for the lateral vibration frequency equations of compressed straight bars with constant cross section on elastic foundations is deduced in this paper. Each particular case under the conditions at the end of the bar is analysed and discussed.

Abstract:The concept of mass center coordinate system is introduced. The definition of missile coordinate system is modified. The general trajectory simulation model with mass center's flow and bias under consideration is presented and the respective formulas for moment of inertia and product of inertia are given.

Abstract:In this paper, a systematic error observation model for multiple radars is established, on the basis of which the system observability is analyzed and a conclusion is drawn that measurement accumulation does not always lead to higher observability. According to the conclusion a measurement subset can be produced by means of data selection, which causes higher system observability, to estimate the systematic error . Simulation result shows that the method proposed in this paper can ensure the validity of estimation algorithm.

Abstract:In this paper, it is discussed how to detect the low SNR small moving target in the condition of complicated background. A space high pass filtering method is presented to improve the image quality for restraining the background noise and enhancing the small target, then the likelihood ratio detection theory is used to pick out a small number of possible moving targets and the neighborhood judging method is presented to pick out the smaller number of possible moving targets. Finally, the true target motion trajectory is detected in multi-frame successive image by use of image flow analysis method. The experiment result indicates that this algorithm can reliably detect small target's motion, even the point target's.

Abstract:The motion compensated discrete cosine transform coding is an efficient video coding technique. In resent years, it has been adopted for many standards of video coding, such as the very low video coding-H.263. considering the sensitivity of image edge information, we classified the coding blocks based on the features of edge, made the quantization noise near an edge appear edgelike itself, then reserved the sensitive DCT coefficients optimaly, and improved the image quality at high coding efficiency.

Abstract:Dihedral corner reflector is an important geometry because it is a basic canonical shape that exhibits a double-bounce phenomenon. The Inverse Fourier transform is used in conjunction with the frequency-domain description to obtain a high-frequency analytical approximation to the impulse response of the dihedral reflector. An amplitude modulated(AM) pulse is convolved with the impulse response of the target to yield the range profile signature.

Abstract:A new method for speech denoising is presented which uses a new threshold different from DJ's thresholds. Preliminary computer simulations were performed on speech signals and resulted in better performance than that by using DJ's thresholds.

Abstract:The fundamentals and structure of an electromagnetic probe for measurement of HPM is described in this paper. The design's theoretical data and calibration procedure and the results of this kind of probe are given. It is characterized by its capability of carrying much higher power of microwave, good airtightness, simple structure and easy operation. It is an effective and practical way to measure the peak power of HPM.

Abstract:By means of the C++Builder powerful component technology and multithread technology, a 32-bit serial communication component instead of the traditional DLL can be applied to the serial communication device in ATVM and reduce the burden in developing the application software.

Abstract:In this paper, according to the features of parallel object-oriented database and asynchronous parallel query execution strategy, a class-based hybrid data placement strategy is proposed, which consists of two parts: the hybrid data partition strategy and the class-based data allocation strategy.

Abstract:Boundary-Scan Technique(BST) is a new and effective way of test and design-for-testability for VLSI circuits. In order to use BST more efficiently, it is necessary to study the basic theory of boundary-scan test thoroughly and precisely. In this paper, A mathematical model of boundary-scan test process is set up based on Boolean Matrix theory. Then, by applying the model established, two boundary-scan test generation principles are presented. The first one gives the sufficient condition for fault detection in boundary-scan test. The second gives the sufficient condition for fault isolation and diagnosis in boundary scan test. The mathematical model and its deduction constitute the theoretical basis of boundary scan test, which can be used in developing test generation algorithms with better property.

Abstract:The spherical gear formed by attributing ring teeth on a spherical face is a new type of gear. The spherical gear device can be used to deliver spherical motion. In order to popularize its application, it is necessary to study its manufacture. Base on the study of configuration characteristic of the spherical gear, extending the generating method principle of general gear's manufacture to the spherical gear's manufacture, we ratiocinate out the generating method principle of spherical gear's manufacture. On precondition of applying generating method, we design the scheme of turning and milling of the spherical gear, and we work out a suit of device accessioned on the lathe for manufacturing spherical gears. It provides a basic means for studying the manufacture of spherical gears.

Abstract:This paper presents an ultraprecision air bearing capacitive sensor with high resolution. It combines the air bearing gauge head with a square guideway with the microminiature capacitive sensor, ensuring high accuracy and high frequence response It's suitable for ultraprecision contact measurement.

Abstract:Now the radio system is developing towards software radio.So how to realize the conversion of high speed RF sampling data down to low speed base band data becomes a key problem. On the basis of the introduction of software radio, this paper puts forward design schemes to use multirate signal processing and efficient digital decimate filter to downconvert, then analyzes and compares them.

Abstract:The theory of American option pricing has finally come to a problem about optimal stopping. In the paper We discuss opitimal stopping of diffusion processes, because we deal with diffusion processes in the American option pricing. Especially, a payment function with discount are discussed.

Abstract:In this paper, we construct the network model of the minimum cost tree in the network with node weight function θand edge weight ω .We also discuss the complexity of the problem and give algorithms to solve the problem.

Abstract:We have obtained two criteria of three classes of local rings in commutative algebra with homological methods.

Abstract:In this paper, we study the equation of the title with D general. The equation has nontrivial integer solutions, only when D=7, 26, 31, 38 or 61, for 0

Abstract:The Copolymerization of 1, 4-Bis(chloromethyl)-2-methoxy-5-octyloxy benzene and 1, 4-Bis(ch1oromethyl)-2, 5-dimethyl benzene produces soluble copolymer, The structure of polymer is determined by IR and ¹HNMR.

Abstract:Trialkylborane is synthesized by modified organometalic route in the presence of ultrasound, as a result, the yield is higher and the reaction time is reduced.