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A purchase constraint matrix is constructed to outline the constraints and is followed by the implications to marketing managers and researcher.


By employing the QR decomposition of the constraint matrix and the eigensystem decomposition of reduced projective Hessian matrix in the subproblem, the authors form affine scaling modified gradient curvilinear path very easily.


Namely, if the parametric problem is specified on the entire axis, then the constraint matrix elements are regular at degeneration points of two levels.


This new formulation is almost minimal in terms of the number of variables and constraints and of the density of the constraint matrix.


We show that, for problems in which the constraint matrix is carelessly constructed with random entries, with probability one only one between primal degeneracy and dual degeneracy appears.

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 Implicit function representing the relationship among linear network variables, can be used to describe various linear elements and linear multiport networks. For the description of multiport network variables, it is not necessary to d istinquish excitations and responses, or to choose voltage ports and current ports, l mplicit function representations for oneport, twoport and multiport networks are discussed, Hence, the following can be derived: singular oneport elements ( nuIlator and norator ) , and singular... Implicit function representing the relationship among linear network variables, can be used to describe various linear elements and linear multiport networks. For the description of multiport network variables, it is not necessary to d istinquish excitations and responses, or to choose voltage ports and current ports, l mplicit function representations for oneport, twoport and multiport networks are discussed, Hence, the following can be derived: singular oneport elements ( nuIlator and norator ) , and singular twoport element (nullor) , as well as constraint matrix analysis for linear multiport network.  用隐函数表示线性网络的变化关系,可以描述各种类型的线性元件和各种特性的线性多口网络,而且在描述多口网络的端口网络变量时,既不要区分激励量和响应量,也无需选定电压口和电流口。文章讨论了隐函数表示法对单口、双口及多口网络的描述,并由此引出奇异单口元件维零器、维非器、奇异双口元件零非器及线性多口网络的约束矩阵分析法。  In this paper an approach of AGC and EDC with security constraints is proposed. The integration of ACE is considered an incremental cost of delivered power in economic dispatch computation by coordination equation method. Transmission losses are considered BCoefficient method. In order to check possible overload in the network, a security constraint matrix is constructed using DC load flow method. In this method conditions for security constraints are calculated offline and overload limits are... In this paper an approach of AGC and EDC with security constraints is proposed. The integration of ACE is considered an incremental cost of delivered power in economic dispatch computation by coordination equation method. Transmission losses are considered BCoefficient method. In order to check possible overload in the network, a security constraint matrix is constructed using DC load flow method. In this method conditions for security constraints are calculated offline and overload limits are checked online. In case if violation of security constraints is detected, a new optimized coordination equation satisfying security constraints can be determined by modifying Lagrangian equation. The computation time for rescheduling only 0.10.2 sec. which is suitable for online implementation.When this is no violation of security constraints, the desired generation of unit PDI is given by eq. (i)(4)(see Chinese paper). The block diagrams of automatic control system and PDI computation in Fig(1) and(2).The conditions for security constraints are calculated offline. According to DC loadflow method the line security constraints can be expressed by eg. (7) and (8), whereS(or B) is sensitivity matrix. The dimension of B matrix can be reduced by columns in two steps: First, check BKi in Kth column satisfies eq.(9) and (10),then B matrix will be reduced to D matrix. Second, compare each column of D matrix with other columns. If Rth column of D satisfies eq.(11), then the security constraints can be express by eq. (12). If the dimension of matrix SPN was 135×1 originally, after the two steps computation, dimension of matrix GPN(in eq. (12)) became 23 ×1. Consequently only 23 critical lines are necessary to be verified for security constraints.Even by using eq. (12) to check security limit is still rather timeconsuming. It can be further simplified by. using method of reference generator. Let us choose a generator H which is within security limit as the reference generator, Assuming bH = f (PH) and b = f (P1),we can determine P1 = f (PH) by relation of coordination equation b1/(1  σ1) = bH/(1σH). Then the security constraints can be express by eq.(15), computating each column in MPH + N, we have PHA and PHB, Then the necessary and sufficient condition for online checking security limit, expessed by eq.(16).When an overload is detected, it is only necessary to use the modified coordination equation (21), where σKi is the remedial coefficient of Kth overload line, which is computed by eqs. (17)(20). When the solution is found, we should .check the security constraints again and repeat the above computation process until all the security constraints are satisfied..  本文介绍考虑了线路安全约束条件的自动发电控制和经济调度控制,全系统的供电微增成本“λ”用区域控制误差(ACE)的积分值来表示。经济负荷分配用传统的协调方程式法,其中线损修正采用了B系数。安全约束条件先由离线计算好,经过缩减 后用于在线校核。当检出有违反安全约束条件时,求出越限修正系数σ_(Ki),加入新的协调方程式进行再调度,其计算时间为0.1～0.2秒,满足在线应用的要求。  This is an attempt to give a method of railway profile automation design by means of digital terrain model. A mathematical model for railway profile optimization design is given. And the paper explains how to calculate the negative gradient of the objective function, to form the constraint matrix, to obtain the terrain information by using digital terrain model and to construct an initial feasible profile automatically by computer. According to the procedure of railway profile design a system of computer... This is an attempt to give a method of railway profile automation design by means of digital terrain model. A mathematical model for railway profile optimization design is given. And the paper explains how to calculate the negative gradient of the objective function, to form the constraint matrix, to obtain the terrain information by using digital terrain model and to construct an initial feasible profile automatically by computer. According to the procedure of railway profile design a system of computer program was completed. By using the program system railway profiles of two sections were desiged. The results appear satisfactory.  本文给出了一种用数字地面模型进行铁路纵断面自动设计的方法。文中叙述了铁路线路纵断面优化设计的数学模型;阐述了目标函数负梯度的计算方法、约束矩阵的结构、利用数模获取地形资料的方法以及由电子计算机生成初始纵断面的方法。作者根据纵断面设计的步骤,编制了相应的程序系统,并用所编程序对实际线路纵断面进行了自动设计,结果令人满意。文末示出算例。   << 更多相关文摘 
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