Showing papers on "Computation published in 1976"
TL;DR: It is shown that this algorithm successfully extracts information from random-dot stereograms, and its implications for the psychophysics and neurophysiology of the visual system are briefly discussed.
Abstract: The extraction of stereo-disparity information from two images depends upon establishing a correspondence between them. In this article we analyze the nature of the correspondence computation and derive a cooperative algorithm that implements it. We show that this algorithm successfully extracts information from random-dot stereograms, and its implications for the psychophysics and neurophysiology of the visual system are briefly discussed.
1,392 citations
01 May 1976
TL;DR: The CNS needs to be understood at four nearly independent levels of description: that at which the nature of a computation is expressed; that atWhich the algorithms that implement a computation are characterized; thatat which an algorithm is committed to particular mechanisms; and that atwhich the mechanisms are realized in hardware.
Abstract: : The CNS needs to be understood at four nearly independent levels of description: (1) that at which the nature of a computation is expressed; (2) that at which the algorithms that implement a computation are characterized; (3) that at which an algorithm is committed to particular mechanisms; and (4) that at which the mechanisms are realized in hardware. In general, the nature of a computation is determined by the problem to be solved, the mechanisms that are used depend upon the available hardware, and the particular algorithms chosen depend on the problem and on the available mechanisms. Examples are given of theories at each level. (Author)
642 citations
TL;DR: In this paper, a path independent contour integral formula for the distinct calculation of combined mode stress intensity factors in linear plane elasticity problems is presented, based on a Somigliana type singular integral representation and is easily appended to existing finite element computer codes.
Abstract: A path independent contour integral formula for the distinct calculation of combined mode stress intensity factors in linear plane elasticity problems is presented. The method is based on a Somigliana type singular integral representation and is easily appended to existing finite element computer codes. Numerical results to three problems with known perturbation solutions are given and demonstrate the accuracy and stability of the method.
352 citations
01 Jul 1976
TL;DR: In this article, an algorithm and data structure are presented for searching a file containing N records, each described by k real valued keys, for the m closest matches or nearest neighbors to a given query record.
Abstract: An algorithm and data structure are presented for searching a file containing N records, each described by k real valued keys, for the m closest matches or nearest neighbors to a given query record. The computation required to organize the file is proportional to kNlogN. The expected number of records examined in each search is independent of the file size. The expected computation to perform each search is proportional to logN. Empirical evidence suggests that except for very small files, this algorithm is considerably faster than other methods.
134 citations
01 Jan 1976
95 citations
01 Jul 1976
TL;DR: In this article, a new numerical method used to drastically reduce the computation time required to solve the Navier-Stokes equations at flight Reynolds numbers is described, which makes it possible and practical to calculate many important three-dimensional, high Reynolds number flow fields on computers.
Abstract: A new numerical method used to drastically reduce the computation time required to solve the Navier-Stokes equations at flight Reynolds numbers is described. The new method makes it possible and practical to calculate many important three-dimensional, high Reynolds number flow fields on computers.
93 citations
01 Apr 1976
TL;DR: The method of solution described here avoids exhaustive search procedures by employing an approach utilizing a constrained dynamic programming algorithm to lay out groups of rectangles called strips.
Abstract: A method of solving a version of the two-dimensional cutting-stock problem is presented. In this version of the problem one is given a number of rectangular sheets and an order for a specified number of each of certain types of rectangular shapes. The goal is to cut the shapes out of the sheets in such a way as to minimize the waste. However, in many practical applications computation time is also an important economic consideration. For such applications the goal may be to obtain the best solution possible without using excessive amounts of computation time. The method of solution described here avoids exhaustive search procedures by employing an approach utilizing a constrained dynamic programming algorithm to lay out groups of rectangles called strips. This paper also describes the results obtained when the algorithm was tested with some typical rectangular layout problems.
91 citations
TL;DR: An algorithm for optimum allocation of redundancies in a general system is presented and a heuristic criterion is introduced which takes into account the relative increment in reliability versus increments in constraints.
Abstract: An algorithm for optimum allocation of redundancies in a general system is presented. The method is applicable to problems having any number of constraints which need not be linear. For selecting the subsystem where redundancy is to be added, a heuristic criterion is introduced which takes into account the relative increment in reliability versus increments in constraints. The method is applicable for any system configuration where subsystems are composed of identical parallel elements. The algorithm is simple, requires little computation effort, and is easily programmed for a computer. An example of a nonseries system illustrates the procedure.
70 citations
TL;DR: In this paper, a path independent integral formula is developed for the computation of the intensity of the stress singularity at a right corner where one edge is rigidly fixed and the other is free of traction.
60 citations
TL;DR: This paper presents a method for evaluating the often neglected component, the expected incompletion cost, of the operating cost of a paced line with stochastic task times through a three stage process.
Abstract: This paper presents a method for evaluating the often neglected component, the expected incompletion cost, of the operating cost of a paced line with stochastic task times. This incompletion cost is developed through a three stage process. First presented is a procedure for generating all possible combinations of incompleted tasks. Next is an evaluation of the probabilities and costs of their occurrence. Included are not only a mechanism for generating only those incompletion combinations with a significant probability of occurring, but also various techniques for reducing computer storage requirements and computation time. Finally, these make possible an evaluation of the operating cost of paced lines.
TL;DR: A new two level method is developed for the optimization of non-linear dynamical systems with a quadratic cost function that takes less than half the computation time of the global solution.
TL;DR: An efficient algorithm requiring only the updating of a small portion of the Jacobian matrix when individual solution vectors do not converge is presented, and the storage requirements and computation efforts to obtain a complete solution are estimated.
Abstract: Two major topics are discussed: macromodularity and latency. The macromodular approach uses the tearing procedure, modified nodal analysis, symbolic LU factorization techniques, and separate updating and convergence tests, to take full advantage of large sparse networks with highly repetitive subnetworks. An efficient algorithm requiring only the updating of a small portion of the Jacobian matrix when individual solution vectors do not converge is presented, and the storage requirements and computation efforts to obtain a complete solution are estimated. The latent approach takes advantage of the temporary cessation of network activity between stimulation and response through knowledge of actual stimulation and the history of the internal node voltages. This approach is fully utilized by defining latent directed paths. A "latent graph" theory is proposed, and some results are presented.
TL;DR: Three residue arithmetic algorithms are described for exact computation of the Moore–Penrose inverse of a rectangular matrix with rational elements using a partitioning procedure and an orthgonalization procedure.
Abstract: Residue arithmetic algorithms are described for exact computation of the Moore–Penrose inverse of a rectangular matrix with rational elements.The first algorithm is based on reducing the matrix to Hermite canonical form; the second algorithm uses a partitioning procedure, while the third uses the orthgonalization procedure. A comparison of the estimates for the choice of prime moduli in different algorithms is given.
TL;DR: It is shown that the calculations of spreading resistance correction factors for graded structures can be readily carried out by using a simple recurrence formula for the integration factor that occurs in Schumann and Gardner's multilayer theory.
Abstract: It is shown that the calculations of spreading resistance correction factors for graded structures can be readily carried out by using a simple recurrence formula for the integration factor that occurs in Schumann and Gardner's multilayer theory. The number of layers that can be used in the practical application of this theory has hitherto been limited by the computer core size requirement, because the earlier method of calculating the integration factor requires the inversion of a 2N × 2N matrix for an N-layer approximation. The use of the recurrence formula effectively removes this constraint. In terms of computation time, the recurrence-formula method is also very efficient. The economy thus achieved both in computation time and in core size requirement makes it possible now to make spreading resistance correction a routine matter, without having to resort to such measures as Hu's interpolation and space partitioning scheme.
06 Sep 1976
TL;DR: This paper is concerned with the class of sequentially computable finite type functionals and its enrichments by adding some parallel functionals of various power.
Abstract: This paper is concerned with the class of sequentially computable finite type functionals and its enrichments by adding some parallel functionals of various power.
TL;DR: In this paper, the relative importance of secondary nonlinear effects in soil-structure interaction is investigated by means of the iterative linear method, and an improved algorithm is presented for the computation of the characteristic strain used in the Iterative approach.
Abstract: The relative importance of secondary nonlinear effects in soil-structure interaction are investigated by means of the iterative linear method. It is found that the refinement in the analyses, while increasing the cost of computation several times, does not change the dynamic response in the structure to a significant degree. At the same time, an improved algorithm is presented for the computation of the characteristic strain used in the iterative approach.
TL;DR: A mechanism for the implementation of recursive programs, called production mechanism by opposition to the usual recursion mechanism, which computes bottom-up, starting from the basic values given by halting conditions, and intermediate values leading to the resuit.
Abstract: — In this paper, we de fine and study a mechanism for the implementation of recursive programs: we call it production mechanism by opposition to the usual recursion mechanism. It computes bottom-up, starting from the basic values given by halting conditions, and générâtes intermediate values leading to the resuit. We use for this purpose a translation of a recursive program into a system o f équations in a space ofsets. We introducé determinism conditions providing the uniqueness of the set of intermediate values; we study the structure of this set. As an application, we show the opiimality of an implementation of Ackermann program (Rice's algorithm).
TL;DR: In this article, a numerical scheme for the computation of axisymmetric equilibria in the presence of external conductors, without a conducting shell, is presented, where the plasma boundary is always required to pass through a given point in the equatorial plane of the plasma column.
Abstract: A numerical scheme for the computation of axisymmetric equilibria in the presence of external conductors, without a conducting shell, is presented. The plasma boundary is always required to pass through a given point in the equatorial plane of the plasma column. The relationship between the convergence of the iterative scheme and the position of this point is discussed. The numerical scheme is applied to two relevant problems.
TL;DR: Two algorithms are proposed; one is a straightforward application of the parametric programming technique of quadratic programming, and the other is a modification of the Dinkelbach's method, and it is proved that both are finite algorithms.
Abstract: Consider the nonlinear fractional programming problem max{f(x)lg(x)lxES}, where g(x»O for all XES. Jagannathan and Dinkelbach have shown that the maximum of this problem is equal to ~O if and only if max{f(x)-~g(x) IXES} is 0 for ~=~O. 1 t t Based on this result, we treat here a special case: f(x)=Zx Cx+r x+s, g(X)=~ xtDX+ptX+q and S is a polyhedron, where C is negative definite and D is positive semidefinite. Two algorithms are proposed; one is a straightforward application of the parametric programming technique of quadratic programming, and the other is a modification of the Dinkelbach's method. It is proved that both are finite algorithms. In the computational experiment performed for the case of D=O, the followings are observed: (i) The parametric programming ap proach is slightly faster than the Dinkelbach's, but there is no significant difference, and (ii) the quadratic fractional programming problems as above can usually be solved in computation time only slightly greater (about 10-20%) than that required by the ordinary (concave) quadratic programming problems.
TL;DR: In this paper, a technique based on the perpendicular-plane angular coordinate system and a two-variable finite Fourier-Hermite series is presented for calculating VCP at a large number of observer positions in a room.
Abstract: A computational technique has been developed and applied to the problem of computation of ESI at a large number of observer positions in a room. The technique is based on the perpendicular-plane angular coordinate system and a two-variable finite Fourier-Hermite series for interpolating discrete two-variable data. A simple extension of this technique is presented for calculating VCP at a large number of observer positions in a room.
TL;DR: Two algorithms are presented for the rapid and exact computation of the area within a closed polygonal boundary, and for determining the coordinates of the center of mass of that area by a Stokes' Theorem transformation.
Book•
01 Jan 1976
TL;DR: Experimental results are presented for the computation of linear equations and matrix inversion using digital-stochastic-computing structures that provide very economical and fast online computations.
Abstract: The problem of online computation of linear equations and matrix inversion using digital-stochastic-computing structures is considered. Such techniques are shown to provide very economical and fast online computations. The simple logic circuits used for the realisation of the stochastic operators are ideally suited for large-scale integrated-circuit fabricatioo. Experimental results are presented for the computation nf linear equations and matrix inversion.