The problem of segmenting aerial photographs can generally not be solved in a reasonable manner by use of the information in the image alone. In this paper we present a structured approach to the problem, which in add...
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The problem of choosing tickmarks for nonlinear scales is of interest for some kindsof diagrams, e.g., nomograms and contour plots. A method for getting “nice”values at the tickmarks is discussed based on a database...
Die Lösungen des Coulombschen Reibungsproblems für starre Körper in zwei Dimensionen werden analysiert. Das bestimmende System von gewöhnlichen Differentialgleichungen und Ungleichungen wird aufges...
Die Lösungen des Coulombschen Reibungsproblems für starre Körper in zwei Dimensionen werden analysiert. Das bestimmende System von gewöhnlichen Differentialgleichungen und Ungleichungen wird aufgestellt. Beispiele werden vorgelegt, die einige ungewünschte Eigenschaften dieses speziellen Reibungsgesetzes nachweisen. Hinreichende Bedingungen für Existenz und Eindeutigkeit werden mit Hilfe der Theorie der linearen Komplementarität hergeleitet. The solutions to the Coulomb friction problem for rigid bodies in two dimensions are analyzed. The governing system of ordinary differential equations and inequalities is derived. Examples are presented demonstrating undesirable properties of this particular law of friction. Sufficient conditions for existence and uniqueness are given using the theory of linear complementarity.
A design process for a query language based on set algebra is described. Key principles used in the design are: make explicit assumptions about the end users background, delimit the scope of the language, and make it ...
A design process for a query language based on set algebra is described. Key principles used in the design are: make explicit assumptions about the end users background, delimit the scope of the language, and make it simple by omitting all features that have not been found necessary. The language closely mirrors concepts well known from algebra and set theory: it contains no join or relational division, and it has a high expressive power.
Computer Vision has now reached a level of maturity that allows us not only to perform research on individual methods but also to build fully integrated computer vision systems of a signi cant complexity. This opens u...
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ISBN:
(数字)9783540492566
ISBN:
(纸本)9783540654599
Computer Vision has now reached a level of maturity that allows us not only to perform research on individual methods but also to build fully integrated computer vision systems of a signi cant complexity. This opens up a number of new problems related to architectures, systems integration, validation of - stems using benchmarking techniques, and so on. So far, the majority of vision conferences have focused on component technologies, which has motivated the organization of the First International Conference on Computer Vision Systems (ICVS). It is our hope that the conference will allow us not only to see a number of interesting new vision techniques and systems but hopefully also to de ne the research issues that need to be addressed to pave the way for more wide-scale use of computer vision in a diverse set of real-world applications. ICVS is organized as a single-track conference consisting of high-quality, p- viously unpublished, contributed papers on new and original research on c- puter vision systems. All contributions will be presented orally. A total of 65 papers were submitted for consideration by the conference. All papers were - viewed by three reviewers from the program committee. Thirty-two of the papers were selected for presentation. ICVS’99 is being held at the Alfredo Kraus Auditorium and Convention Centre, in Las Palmas, on the lovely Canary Islands, Spain. The setting is spri- like, which seems only appropriate as the basis for a new conference.
A linear optimization problem is the task of minimizing a linear real-valued function of finitely many variables subject to linear con straints; in general there may be infinitely many constraints. This book is ...
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ISBN:
(数字)9781461211426
ISBN:
(纸本)9780387908571
A linear optimization problem is the task of minimizing a linear real-valued function of finitely many variables subject to linear con straints; in general there may be infinitely many constraints. This book is devoted to such problems. Their mathematical properties are investi gated and algorithms for their computational solution are presented. Applications are discussed in detail. Linear optimization problems are encountered in many areas of appli cations. They have therefore been subject to mathematical analysis for a long time. We mention here only two classical topics from this area: the so-called uniform approximation of functions which was used as a mathematical tool by Chebyshev in 1853 when he set out to design a crane, and the theory of systems of linear inequalities which has already been studied by Fourier in 1823. We will not treat the historical development of the theory of linear optimization in detail. However, we point out that the decisive break through occurred in the middle of this century. It was urged on by the need to solve complicated decision problems where the optimal deployment of military and civilian resources had to be determined. The availability of electronic computers also played an important role. The principal computational scheme for the solution of linear optimization problems, the simplex algorithm, was established by Dantzig about 1950. In addi tion, the fundamental theorems on such problems were rapidly developed, based on earlier published results on the properties of systems of linear inequalities.
N COMPUTER applications we are used to live with approximation. Var I ious notions of approximation appear, in fact, in many circumstances. One notable example is the type of approximation that arises in numer&#...
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ISBN:
(数字)9783642584121
ISBN:
(纸本)9783540654315;9783642635816
N COMPUTER applications we are used to live with approximation. Var I ious notions of approximation appear, in fact, in many circumstances. One notable example is the type of approximation that arises in numer ical analysis or in computational geometry from the fact that we cannot perform computations with arbitrary precision and we have to truncate the representation of real numbers. In other cases, we use to approximate com plex mathematical objects by simpler ones: for example, we sometimes represent non-linear functions by means of piecewise linear ones. The need to solve difficult optimization problems is another reason that forces us to deal with approximation. In particular, when a problem is computationally hard (i. e. , the only way we know to solve it is by making use of an algorithm that runs in exponential time), it may be practically unfeasible to try to compute the exact solution, because it might require months or years of machine time, even with the help of powerful parallel computers. In such cases, we may decide to restrict ourselves to compute a solution that, though not being an optimal one, nevertheless is close to the optimum and may be determined in polynomial time. We call this type of solution an approximate solution and the corresponding algorithm a polynomial-time approximation algorithm. Most combinatorial optimization problems of great practical relevance are, indeed, computationally intractable in the above sense. In formal terms, they are classified as Np-hard optimization problems.
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