Decomposition theorem andk-hyper connection expressions for generalk-order cofactors

Twok-hyperconnection expressions of a generalk-order cofactorY(_i,j) are presented for the indefinite parameter matrixY of a linear system by applying directed hypergraph theory, and based on it a decomposition theorem ofY(_i,j) is derived. By this theorem, the multi-level tearing and analysis can be carried out easily for any linear large system. This is a new multilevel topological analysis method. Using proposed method the scale of systems which can be topologically analysed by a computer will be enlarged.     

一般k阶余因式的k超连接表达式和分解定理

本文应用有向超图理论提出了线性系统不定参数矩阵Y的一般k阶余因式Y(ii)的两个k超连接表达式,并根据它导出了Y(ii)的一个分解定理。应用该定理容易对任意线性大系统进行多层撕裂和分析。这是一种新的多层拓扑分析方法,它可以扩大一台计算机所能拓扑分析的系统规模。     

含有受控源的线性电路的叠加原理研究

用叠加原理分析计算含有受控源的线性电路时,独立源可以单独作用,受控源是不能单独作用的。因为受控源单独作用只能求出与控制量有关的未知量,不能计算出具体值,具体值需要通过应用叠加原理才能计算出来,这是不符合叠加原理概念的。但是受控源单独作用作为一种计算方法还是可以的。     

激光微区发射光谱分析法测定硫氧化钇钐中的钐

本文以激光微区发射光谱分析仪和CCD光学多道分析仪组成分析系统,通过对样品多次采集和用数理统计法对数据进行处理,以SmII443.434nm为分析线,测定了Y2O2S:Sm3+长余辉材料中Sm的含量。分析结果表明:分析谱线相对强度RSD为5.01%,定量分析相对标准偏差RSD为8.96%,分析结果的平均值为2.018%;与制备前材料的百分含量比较,采用共沉淀法制备Y2O2S:Sm3+长余辉材料中Sm百分含量明显增大。     

论电路齐次定理和叠加定理的关系

齐次定理和叠加定理是由线性线性电路两个重要的定理。通过分析,指出对单一激励的电路,如果该电路满足齐次定理或者叠加定理,那么,该电路一定是线性电路。对单一激励的电路,齐次定理已经充分表达了线性电路的线性性质。对多个激励的电路,如果该电路满足可加性,那么,该电路一定是线性电路。反之,如果电路仅满足齐次定理,则该电路不一定是线性电路。尽管叠加定理是线性系统可加性在电路中的应用,但叠加定理和可加性的内涵是有所区别的,不能通过电路是否满足叠加定理来判定电路的齐次性或电路是否满足齐次定理。本文的讨论可供讲授电路理论课程的教师参考。     

A Cut Set Method for Reliability Evaluation of Systems Having s-Dependent Components

The cut set method presently assumes components to be s-independent. This paper presents a method called MCS approach for extending the cut set approach to systems involving s-dependencies. The method is based on MCS theorem and consists in decomposing the system by cut sets and using the Markov processes for calculating terms in the cut set equations. The Markov process associated with only the members of one cut set need be considered at a time and the transition rate matrix of the entire system need not be generated. The MCS approach is feasible when Pr{C?i} and F(S) can be calculated from the transition rate matrix of the members of Ci. This is possible when the MCS theorem applies and the MP of the entire system can be merged to obtain the MP of Ci. However, in many situations where the MCS theorem does not rigorously apply, approximate results may still be possible by the MCS method. The judgment in such cases is based on how approximately does the MCS theorem apply.     

THE ANALYSIS METHOD OF THE SETS OF BRANCHES BASED ON INDEPENDENT LOOPS IN THE ELECTRIC NETWORK

The matrix D describing relations of the loops to the nodes in the graph and also the setsof branches based on the independent loops and their matrix Q are defined.The theorem in whichthe product of the loop-node matrix D multiplied by the incidence matrix A_a is equal to matrix Qis put forward and proved.The admittance matrix Y_(lc) of the sets of the branches is defined and it isassumed that the vector V_(lc) of voltage of the sets of branches to be a calculative quantity.The equa-tion of the sets of branches is derived and the analysis method of the sets of branches based on theindependent loops in the electric network is presented.     

Successive encoding of correlated sources

The encoding of a discrete memoryless multiple source{( X_{i}, Y_{i})}_{i=1}^{infty}for reconstruction of a sequence{Z_{i}}_{i=1}^{infty}}, withZ_{i} = F( X_{i}, Y_{i}); i = 1,2, cdotsis considered. We require that the encoding should be such that{X_{i}}_{i=1}^{infty}is encoded first without any consideration of{Y_{i}}_{i=1}^{infty}, while in a second part of the encoding, this latter sequence is encoded based on knowledge of the outcome of the first encoding. The resulting scheme is called successive encoding. We find general outer and inner bounds for the corresponding set of achievable rates along with a complete single letter characterization for the special caseH( X_{i}|Z_{i}, Y_{i}) = 0. Comparisons with the Slepian-Wolf problem and the Ahlswede-Korner-Wyner side information problem are carried out.     

基于Shilnikov定理构造分段线性混沌系统

该文基于异宿轨道Shilnikov定理,构造了一类分段线性混沌系统。这类混沌系统具有至少两个平衡点,且在各个平衡点处具有相同的雅戈比矩阵。通过改变系统的平衡点及相应转换平面,可以得到这类混沌系统的其他形式。理论研究和实验证明了该方法的有效性。     

Noiseless coding of error detection information (Corresp.)

Correlated information sequences{X_{i}}and{Y_{i}}are generated by a source and receiver, respectively. The least number of bits per source character that must be given to the receiver to allow perfect detection of errors in the sequence{Y_{i}}is found. The performance of error detecting codes used over noisy channels is characterized by this result.     

Faster image template matching in the sum of the absolute value ofdifferences measure

Given an mxm image I and a smaller nxn image P, the computation of an (m-n+1)x(m-n+1) matrix C where C(i, j) is of the form C(i,j)=Sigma(k=0)(n-1)Sigma(k'=0) (n-1)f(I(i+k,j+k'), P(k,k')), 0=/相似文献   

模拟电路故障诊断的结点电压灵敏度比值法

在证明线性电路中结点电压变化量比值等于结点电压灵敏度比值的基础上,提出了结点电压灵敏度比值法,通过结点电压变化量比值和结点电压灵敏度比值的比对确定电路的故障元件。理论分析和实验结果表明,该方法算法简单、诊断速度快,在可测点受限条件下具有较高的诊断精度,特别适合大规模线性模拟电路的故障诊断和测试。     

受控源当作独立源处理的叠加定理分析方法

就应用叠加定理求解含线性受控源电路响应的有关问题进行探讨,特别提出了将线性受控源视为独立源来求解电路响应的新方法。这种方法虽不意味着是解决含线性受控源电路问题的最好的方法,但它却是应用叠加定理的一种行之有效的分析方法。     

Optimal-arrangement and importance of the components in aconsecutive-k-out-of-r-from-n:F system

The authors examine: the determination of an optimal consecutive k-out-of-r-from-n:F system, under permutations of the components, and the Birnbaum-importance of components in the i.i.d. case. The authors first study (theorem 1) the optimality of a general system, with not necessarily s-identical components, under permutation of the components. Then they study (theorem 2) the importance of components in the i.i.d. case. Theorem 2 is readily derived from theorem 1. The main results are given in theorems 1 and 2, and proofs are given. The assumptions are: the system and each component are either good or failed: all binary component states are mutually statistically independent, and all n can be arranged in any linear order; and the system fails if and only if within r consecutive components, there are at least k failed ones     

A dichotomy of functionsF(X, Y)of correlated sources(X, Y)

Consider separate encoding of correlated sourcesX^{n}=(X_{l}, cdots ,X_{n}), Y^{n} = (Y_{l}, cdots ,Y_{n})for the decoder to reliably reproduce a function{F(X_{i}, Y_{i})}^{n}_{i=1}. We establish the necessary and sufficient condition for the set of all achievable rates to coincide with the Slepian-Wolf region whenever the probability densityp(x,y)is positive for all(x,y).     

Frequency-scanned reflection gratings with integrated polarizer

A frequency-scanned reflection grating (blazed grating) with polarizer properties is investigated. The grating structure considered consists of a periodic array of double-dipole elements etched on a dielectric substrate and placed over a ground plane. The two dipoles within a periodic cell are displaced and tilted from each other. Numerical results are presented showing that this grating structure can be designed to have the property of efficiently converting the power of an incident linear polarized wave into a circular polarized diffracted wave. A design is also outlined where the grating acts as a twist reflector, converting an incident linear polarized transverse electric wave into a first-order diffracted transverse magnetic wave. The theoretical analysis is based on Floquet's theorem and the method of moments. Experimental results verifying the numerical results are also presented     

Some results on robust stability of general input-output systems

We consider general input-output systems governed by nonlinear operator equations that relate the system's input, state, and output. The systems under consideration need not be of a feedback type. Assuming that the governing equations depend on a parameterA in a linear space that is allowed to vary in a vicinity N_r(A₀) of a nominal valueA ₀, we study conditions under which the system is stable for each AN_r (A₀), i.e., when the system is robust. By stability we essentially mean that the input-output map is continuous. Depending on the type of continuity used, two concepts of robustness are introduced. The main theorem shows that a certain generalized monotonicity condition imposed on the nominal system combined with a Lipschitz-like condition imposed on the perturbed system guarantees robustness. Moreover, several particular cases of the governing equations are investigated. As examples, we consider (1) a singular system of nonlinear ordinary differential equations (a semistate equation), (2) a feedback system, and (3) a feedback, feedforward system. At the end of this paper some extensions and modifications of the presented theory are discussed.     

Sufficient conditions for the existence of optimum beam patterns for unequally spaced linear arrays with an example

Dolph's method for determining the optimum element currents for half-wavelength equispaced discrete linear arrays is generalized to symmetric discrete linear arrays. The theorem proved gives sufficient conditions for the existence of optimum beam patterns for arrays with elements symmetrically positioned about the array center, but with fixed unequal spacings between the elements. The conditions are such that the Remes exchange algorithm for minimax approximation of functions can be employed to compute the optimum element currents corresponding to an optimum beam pattern directly from the given spacings of the elements. Half-wavelength spaced linear arrays satisfy the conditions of the theorem; therefore, it provides a new method of calculating the well-known Dolph-Chebyshev element currents. An example with unequal spacings is included to show the utility of the method even when the hypotheses of the theorem may not be met.     

Multidimensional velocity filters for visual scene analysis in automotive driver assistance systems

Automotive scenery often contains objects that can be classified by object speed and movement direction. These features can be extracted from video data by linear n-D filters, which have already been analyzed in the past. While soundness of results was convincing, interest in those systems declined due to the reduced computational abilities of contemporary computers. Modern hardware allows realization of velocity filters, if the n-D system is carefully adapted to the analysis problem. The present paper analyzes the premises for application of velocity filters in the domain of automotive driver assistance systems, i.e. with respect to detectability of objects and implementability in a cost effective way. Especially the influence of the frame rate and the temporal violation of the sampling theorem are analyzed. Transfer functions for n-D filters working in a vision-based blind spot collision avoidance system are presented and discussed, and promising approaches for future application fields are proposed.     

Coding the vertexes of a graph

Given a graphGofnnodes. We wish to assign to each nodei(i = 1, 2, cdots n)a unique binary codec_{i}of lengthmsuch that, if we denote the Hannuing distance betweenc_{i}andc_{j}asH(c_{i}, c_{j}), thenH(c_{i}, c_{j})leq Tif nodesiandjare adjacent (i.e., connected by a single branch), andH(c_{i}, c_{j}) geq T+1otherwise. If such a code exists, then we say thatGis doable for the value ofTand tn associated with this code. In this paper we prove various properties relevent to these codes. In particular we prove 1) that for every graphGthere exists anmandTsuch thatGis doable, 2) for every value ofTthere exists a graphG̃which is notTdoable, 3) ifGisT'doable, then it isT'+ 2pdoable forp = 0, 1, 2, cdots, and is doable for allT geq 2T'ifT'is odd, and is doable for allT geq 2T' + 1ifT'is even. In theory, the code can be synthesized by employing integer linear programming where eitherTand/ormcan be minimized; however, this procedure is computationally infeasible for values ofnandmin the range of about10or greater.