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Showing papers on "Topology (electrical circuits) published in 1981"


Journal ArticleDOI
TL;DR: In this article, a new model for the study of power system stability via Lyapunov functions is proposed, which is an assumption of frequency-dependent load power, rather than the usual impedance loads which are subsequently absorbed into a reduced network.
Abstract: A new model for the study of power system stability via Lyapunov functions is proposed. The key feature of the model is an assumption of frequency-dependent load power, rather than the usual impedance loads which are subsequently absorbed into a reduced network. The original network topology is explicitly represented. This approach has the important advantage of rigorously accounting for real power loads in the Lyapunov functions. This compares favorably with existing methods involving approximations to allow for the significant transfer conductances in reduced network models. The preservation of network topology can be exploited in stability analysis, with the concepts of critical and vulnerable cutsets playing central roles in dynamic and transient stability evaluation respectively. Of fundamental importance is the feature that the Lyapunov functions give a true representation of the spatial distribution of stored energy in the system

641 citations


Journal ArticleDOI
TL;DR: In this paper, the authors developed the theoretical basis for determining the bad measurement detectability properties of the state estimator from the topology of the 1-line diagram and the locations of the measurements.
Abstract: A power system static-state estimator has the ability to detect and purge some measurement errors. This paper develops the theoretical basis for determining the bad measurement detectability properties of the state estimator from the topology of the 1-line diagram and the locations of the measurements. Based on this theory, an algorithm is described that: 1) identifies those measurements that have detectable error residuals; and 2) determines the regions of measurement error residual spread.

159 citations


Journal ArticleDOI
TL;DR: A new interconnection topology for incrementally expansible multicomputer systems is described, which combines the easy expansibility of tree structures with the compactness of the n-dimensional hypercube.
Abstract: A new interconnection topology for incrementally expansible multicomputer systems is described, which combines the easy expansibility of tree structures with the compactness of the n-dimensional hypercube. The addition of n-cube links to the binary tree structure provides direct paths between nodes which have frequent data exchange in algorithms such as sorting and fast Fourier transforms (FFT's). The derivation of a family of such Hypertree structures is outlined, and the basic properties such as average path length, uniformity of the distribution of message traffic, and routing algorithms are analyzed.

154 citations


Journal ArticleDOI
J. Hayes1

30 citations



Journal ArticleDOI
TL;DR: In this paper, a technique for the detection of topology errors within an "unobservable" portion of a system is given, based on the Jacobian equivalent concept.
Abstract: A technique for the detection of topology errors within an "unobservable" portion of a system is given. The method is based on the Jacobian equivalent concept. If good information about the observable system state is available from a state estimator, it is possible to detect many external single line outages. An index intended to indicate the "discrimination ability" of specific configurations is defined. A small detailed example is presented.

22 citations


Journal ArticleDOI
TL;DR: In this article, the authors consider the problem of designing a failure threshold for a semiconductor device that will survive an electrical overstress environment, considering the fact that there is a distribution in the failure levels for devices having the same part number.
Abstract: Design of electronic circuits which will survive an electrical overstress environment usually requires information on the failure threshold of semiconductor devices. The specification of that failure threshold must consider the fact that there is a distribution in the failure levels for devices having the same part number. This distribution arises from at least two sources. First, manufacturers of devices with the same part number only guarantee that their parts meet the required electrical specifications. Since electrical specifications are usually broad, there are a number of topological designs and processing techniques which will yield devices with those specifications. Thus, a sample of devices with the same part number from different manufacturers is likely to yield devices with significant physical differences. The engineer should suspect that these physical differences will be reflected in a distribution of failure threshold levels.

13 citations


Journal ArticleDOI
TL;DR: The branch and bound technique is used to obtain an optimal relationship diagram for the departments of the layout, and the planar graph's dual graph is found which gives the topology of the proposed final layout.

13 citations



Journal ArticleDOI
01 Dec 1981
TL;DR: Lumped/distributed networks are analysed using state-space techniques and the time response, for any set of inputs, is obtained without the need of either the explicit form of the transfer function or the use of convolution.
Abstract: Lumped/distributed networks are analysed using state-space techniques. The state and output equations are derived using topological methods with no restrictions on the topology. The method is applied to noncommensurate circuits and to coupled transmission-line circuits in inhomogeneous media. Computer programs have been developed for the analysis of these circuits in both the frequency and time domains. The time response, for any set of inputs, is obtained without the need of either the explicit form of the transfer function or the use of convolution.

10 citations


Journal ArticleDOI
TL;DR: In this article, a two-phase sequence of weight minimization is proposed as an approximate method for optimizing truss geometry and topology in preliminary design, where the initial geometry is held fixed while member sizes are optimized.
Abstract: A two-phase sequence of weight minimization is proposed as an approximate method for optimizing truss geometry and topology in preliminary design. In the first phase, the initial geometry is held fixed while member sizes are optimized. In the second phase, the nodal coordinates are optimized. The advantages of the heuristic method lie in reducing the number of structural analyses and in the control it offers the designer. Through the proposed technique, a reasonable initial geometry may be obtained which allows optimization of the topology of the structure.


Journal ArticleDOI
TL;DR: The main result indicates that permuting, coupling, and partitioning capabilities can be obtained by using 2, 3, and 4-state cells, respectively, in a large class of network topologies.
Abstract: Investigates generalizations of triangular permuting networks in two directions: the connecting power of cells and the network topology. The main result indicates that permuting, coupling, and partitioning capabilities can be obtained by using 2-, 3-, and 4-state cells, respectively, in a large class of network topologies.

Journal ArticleDOI
TL;DR: The definitions and properties of well-known network topology for the three-dimensional case are extended and its network dual and retrieval dual, as defined later, are interesting and useful.

Journal ArticleDOI
TL;DR: A method for generating equivalent networks with minimum sensitivities is presented, applicable to both passive and active linear time invariant networks, and demonstrated on active networks.
Abstract: A method for generating equivalent networks with minimum sensitivities is presented, applicable to both passive and active linear time invariant networks. Special transformation matrices can modify the element values and topology, and can grow elements into the network. First-order sensitivities of the transformed networks are obtained and subjected to minimization. As a result, networks with a larger number of components but smaller individual sensitivities can be obtained. The method is demonstrated on active networks.

Journal ArticleDOI
TL;DR: In this article, it was shown that 2 2 c non-isomorphic group topologies on the real line are non-locally compact, connected, locally compact and compactly generated.


Patent
27 Oct 1981
TL;DR: In this paper, a process automatically generates topology data for fabricating large scale integrated circuits is described, where technology data, a logic function description and logic circuit components are generated and input to a data processing system together with geometric dimension data descriptive of the basic elements of the logic circuits components.
Abstract: A process automatically generating topology data for fabricating large scale integrated circuits. Technology data (110), a logic function description and logic circuit components (120) are generated and input to a data processing system together with geometric dimension data descriptive of the basic elements of the logic circuit components (170). The geometric dimension data is assembled into a plurality of intermediate level geometric topology patterns under control of the logic function description and the intermediate level geometric topology patterns are assembled into a prime level geometric topology representative of the logic function description (200). The logic circuit components are merged with the prime level geometric topology (500) to produce a grid array to be fabricated into a large scale integrated circuit.


Journal ArticleDOI
TL;DR: A model for optimization of the bandwidth assignment plan, as well as a solution method based on decomposition into more tractable separate topology and capacity assignment subproblems for DCCS economics.

Journal ArticleDOI
TL;DR: In this paper, an efficient algorithm for the predistortion of networks with arbitrary topology is presented based on a modification of the Levenberg-Marquardt algorithm using small-change transmission sensitivities.
Abstract: This letter presents an efficient algorithm for the predistortion of networks with arbitrary topology. The method is based on a modification of the Levenberg-Marquardt algorithm using small-change transmission sensitivities. A weighted least square error function is formulated and used subsequently in an iterative optimization scheme. The algorithm determines the errors of the transfer function coefficients due to parasitics of the physical network very accurately. Root-finder methods are used to obtain frequency and Q-deviations of poles and zeros. The predistortion of the network is carried out by perturbing the nominal transfer function poles and zeros correspondingly.