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1.
The AI methodology of qualitative reasoning furnishes useful tools to scientists and engineers who need to deal with incomplete system knowledge during design, analysis, or diagnosis tasks. Qualitative simulators have a theoretical soundness guarantee; they cannot overlook any concrete equation implied by their input. On the other hand, the basic qualitative simulation algorithms have been shown to suffer from the incompleteness problem; they may allow non-solutions of the input equation to appear in their output. The question of whether a simulator with purely qualitative input which never predicts spurious behaviors can ever be achieved by adding new filters to the existing algorithm has remained unanswered. In this paper, we show that, if such a sound and complete simulator exists, it will have to be able to handle numerical distinctions with such a high precision that it must contain a component that would better be called a quantitative, rather than qualitative reasoner. This is due to the ability of the pure qualitative format to allow the exact representation of the members of a rich set of numbers.  相似文献   

2.
Companies that provide crane-lorry services are faced with the daily need to perform vehicle and driver allocation and scheduling. Many companies still do this manually due to the lack of suitable technologies. This manual approach is both time consuming and inaccurate and most probably will not lead to an optimized plan that can reduce operational costs. In this paper, we describe the design of a system called Crane Lorry Scheduling System (CLSS) that we have developed for the largest crane lorry company in Hong Kong. A crane lorry company is a company that provides lorries with different types of mounted crane equipment and drivers to service different types of moving and lifting jobs. CLSS is a Web-based application that streamlines communication with customers, subcontractors and employees/lorry drivers. We modeled the lorry-assignment problem as a constraint-satisfaction problem (CSP) algorithm, which we call the Crane Lorry Optimizing Engine (CLOE). CLOE was designed to be easily customizable to match the needs and requirements of different crane lorry companies. We experimented with two versions of CLOE, regular CLOE that finds best solutions and X-CLOE that finds optimal solutions. Results from our tests show that CLOE is faster and generates better quality plans than the manual approach.  相似文献   

3.
Let (X, #) be an orthogonality space such that the lattice C(X, #) of closed subsets of (X, #) is orthomodular and let (, ) denote the free orthogonality monoid over (X, #). Let C0(, ) be the subset of C(, ), consisting of all closures of bounded orthogonal sets. We show that C0(, ) is a suborthomodular lattice of C(, ) and we provide a necessary and sufficient condition for C0(, ) to carry a full set of dispersion free states.The work of the second author on this paper was supported by National Science Foundation Grant GP-9005.  相似文献   

4.
Summary A. N. Habermann recently published some Critical comments on the programming language Pascal. His reproaches are principally that numerous constructs are ill-defined, that there is confusion amongst ranges, types and structures, and that the goto statement should have been abolished. The present reply successively deals with points that are clearly refutable, those which are debatable and those which constitute valid criticism. Its principal aim is to encourage the reader to form his own opinion.  相似文献   

5.
The tensor language of system engineering is applied for formalized structural synthesis of a pipeline processor for measurement data. The formalized synthesis procedure has produced efficient data processing block pipeline and data processing block pipeline assembly structures.Translated from Kibernetika i Sistemnyi Analiz, No. 6, pp. 29–45, November–December, 1991.  相似文献   

6.
This paper presents algorithms for multiterminal net channel routing where multiple interconnect layers are available. Major improvements are possible if wires are able to overlap, and our generalized main algorithm allows overlap, but only on everyKth (K 2) layer. Our algorithm will, for a problem with densityd onL layers,L K + 3,provably use at most three tracks more than optimal: (d + 1)/L/K + 2 tracks, compared with the lower bound of d/L/K. Our algorithm is simple, has few vias, tends to minimize wire length, and could be used if different layers have different grid sizes. Finally, we extend our algorithm in order to obtain improved results for adjacent (K = 1) overlap: (d + 2)/2L/3 + 5 forL 7.This work was supported by the Semiconductor Research Corporation under Contract 83-01-035, by a grant from the General Electric Corporation, and by a grant at the University of the Saarland.  相似文献   

7.
Many real-time embedded systems process event streams that are composed of a finite number of different event types. Each different event type on the stream would typically impose a different workload to the system, and thus the knowledge of possible correlations and dependencies between the different event types could be exploited to get tighter analytic performance bounds of the complete system. We propose an abstract stream model to characterize such an event stream. The model captures the needed information of all possible traces of a class of event streams. Hence, it can be used to obtain hard bounded worst-case and best-case analysis results of a system. We show how the proposed abstract stream model can be obtained from a concrete stream specification, and how it can be used for performance analysis. The applicability of our approach and its advantages over traditional worst-case performance analysis are shown in a case study of a multimedia application.Ernesto Wandeler is a Ph.D. student at the Computer Engineering and Networks Laboratory of the Swiss Federal Institute of Technology, Zurich. His research interests include models, methods and tools for system-level performance analysis of real-time embedded systems. He holds a Dipl. El.-Ing. degree from ETH Zurich. In 2003, he received the Willi Studer Price and the ETH Medal, both from the Swiss Federal Institute of Technology, Zurich. He is a student member of the IEEE and the ACM.Alexander Maxiaguine is a Ph.D. student at the Computer Engineering and Networks Laboratory of the Swiss Federal Institute of Technology, Zurich. His research interests include models and methods for system-level performance analysis and scheduling of embedded multiprocessor architectures, especially for real-time multimedia applications. Maxiaguine has an M.S. in electrical engineering from the Moscow Technical University of Communications and Informatics. He is a member of the IEEE and the ACM.Lothar Thiele is a full professor of computer engineering at the Swiss Federal Institute of Technology, Zurich. His research interests include models, methods and software tools for the design of embedded systems, embedded software and bioinspired optimization techniques. In 1986 he received the Dissertation Award of the Technical University of Munich, in 1987, the Outstanding Young Author Award of the IEEE Circuits and Systems Society, in 1988, the Browder J. Thompson Memorial Award of the IEEE, and in 2000–2001, the IBM Faculty Partnership Award. In 2004, he joined the German Academy of Natural Scientists Leopoldina.  相似文献   

8.
A first-order system F has theKreisel length-of-proof property if the following statement is true for all formulas(x): If there is ak1 such that for alln0 there is a proof of(¯n) in F with at mostk lines, then there is a proof of x(x) in F. We consider this property for Parikh systems, which are first-order axiomatic systems that contain a finite number of axiom schemata (including individual axioms) and a finite number of rules of inference. We prove that any usual Parikh system formulation of Peano arithmetic has the Kreisel length-of-proof property if the underlying logic of the system is formulated without a schema for universal instantiation in either one of two ways. (In one way, the formula to be instantiated is built up in steps, and in the other way, the term to be substituted is built up in steps.) Our method of proof uses techniques and ideas from unification theory.  相似文献   

9.
Data structures are interpreted as sets which may contain repeating elements. An algebraic system close to the integer ring is constructed on these sets.Translated from Kibernetika, No. 4, pp. 82–88, July–August, 1990.  相似文献   

10.
This paper is an informal introduction to the theory of types which use a connective for the intersection of two types and a constant for a universal type, besides the usual connective for function-types. This theory was first devised in about 1977 by Coppo, Dezani and Sallé in the context of-calculus and its main development has been by Coppo and Dezani and their collaborators in Turin. With suitable axioms and rules to assign types to-calculus terms, they obtained a system in which (i) the set of types given to a term does not change under-conversion, (ii) some interesting sets of terms, for example the solvable terms and the terms with normal form, can be characterised exactly by the types of their members, and (iii) the type-apparatus is not so complex as polymorphic systems with quantifier-containing types and therefore probably not so expensive to implement mechanically as these systems.There are in fact several variant systems with different detailed properties. This paper defines and motivates the simplest one from which the others are derived, and describes its most basic properties. No proofs are given but the motivation is shown by examples. A comprehensive bibliography is included.  相似文献   

11.
The number of virtual connections in the nodal space of an ATM network of arbitrary structure and topology is computed by a method based on a new concept—a covering domain having a concrete physical meaning. The method is based on a network information sources—boundary switches model developed for an ATM transfer network by the entropy approach. Computations involve the solution of systems of linear equations. The optimization model used to compute the number of virtual connections in a many-category traffic in an ATM network component is useful in estimating the resource of nodal equipment and communication channels. The variable parameters of the model are the transmission bands for different traffic categories.  相似文献   

12.
Zusammenfassung In der folgenden Arbeit werden zunächst die Begriffe Gesamtschrittverfahren, Einzelschrittverfahren und Relaxationsverfahren allgemein formuliert und dann auf allgemeine lineare Gleichungssysteme angewandt. Im Spezialfall einer Matrix mit verschwindender Hauptdiagonale erhält man so die bekanntenJacobi-, Gauss-Seidel- und Relaxationsverfahren. Satz 1 macht eine Aussage über die Konvergenz des Einzelschrittverfahrens bei allgemeinen, nicht-negativen Matrizen. Der Beweis verläuft ähnlich wie in einem bereits 1948 vonStein undRosenberg [2] behandelten Spezialfall. Als Korollar ergibt sich eine Aussage über die Konvergenz des Relaxationsverfahrens bei nicht-negativen Matrizen. Es wird ferner der Satz 2 über die Konvergenz des Relaxationsverfahrens bei diagonaldominanten Matrizen beweisen.
Summary In this paper we give a general definition what is meant by total-step-, single-step- and successive relaxation iterative method and we apply these concepts on systems of linear equations. In the special case of a matrix with zero diagonal entries we obtain the well knownJacobi-, Gauss-Seidel- and Relaxation iterative method. Theorem 1 gives conditions for the convergence of the singlestep-iterative method for general, non-negative matrices. The proof is similar to that given byStein andRosenberg in [2] (1948) for a special case. A corollary gives conditions for the convergence of the relaxation-iterative method for non-negative matrices. Further on we prove theorem 2 about the convergence of the relaxation-iterative method with diagonally dominant matrices.
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13.
Software engineering programmes are not computer science programmes   总被引:1,自引:1,他引:0  
Programmes in Software Engineering have become a source of contention in many universities. Some Computer Science departments, many of which have used that phrase to describe individual courses for decades, claim software engineering as part of their discipline. However, Engineering faculties claim Software Engineering as a new speciality in the family of engineering disciplines. This paper discusses the differences between traditional computer science programmes and most engineering programmes and argues that we need programmes that follow the traditional engineering approach to professional education and educate engineers whose speciality within engineering is software construction. One such programme is described.  相似文献   

14.
In this paper the problem of routing messages along shortest paths in a distributed network without using complete routing tables is considered. In particular, the complexity of deriving minimum (in terms of number of intervals) interval routing schemes is analyzed under different requirements. For all the cases considered NP-hardness proofs are given, while some approximability results are provided. Moreover, relations among the different cases considered are studied.This work was supported by the EEC ESPRIT II Basic Research Action Program under Contract No. 7141 Algorithms and Complexity II, by the EEC Human Capital and Mobility MAP project, and by the Italian MURST 40% project Algoritmi, Modelli di Calcolo e Strutture Informative.  相似文献   

15.
In this paper, we consider the class of Boolean -functions, which are the Boolean functions definable by -expressions (Boolean expressions in which no variable occurs more than once). We present an algorithm which transforms a Boolean formulaE into an equivalent -expression-if possible-in time linear in E times , where E is the size ofE andn m is the number of variables that occur more than once inE. As an application, we obtain a polynomial time algorithm for Mundici's problem of recognizing -functions fromk-formulas [17]. Furthermore, we show that recognizing Boolean -functions is co-NP-complete for functions essentially dependent on all variables and we give a bound close to co-NP for the general case.  相似文献   

16.
ART: A Hybrid Classification Model   总被引:1,自引:0,他引:1  
This paper presents a new family of decision list induction algorithms based on ideas from the association rule mining context. ART, which stands for Association Rule Tree, builds decision lists that can be viewed as degenerate, polythetic decision trees. Our method is a generalized Separate and Conquer algorithm suitable for Data Mining applications because it makes use of efficient and scalable association rule mining techniques.  相似文献   

17.
The specification of a function is often given by a logical formula, called a -formula, of the following form: xy(x,y). More precisely, a specification is given in the context of a certain theory E and is stated by the judgment E xy (x,y).In this paper, we consider the case in which E is an equational theory. It is divided into two parts. In the first part, we develop a theory for the automated proof of such judgments in the initial model ofE . The validity in the initial model means that we consider not only equational theorems but also inductive ones. From our theory we deduce an automated method for the proof of a class of such judgments. In the second part, we present an automatedmethod for program synthesis. We show how the previous proof method can be used to generate a recursive program for a function f that satisfies a judgment E x (x, f(x)).We illustrate our method with the automated synthesis of some recursive programs on domains such as integers and lists. Finally, we describe our system LEMMA, which is an implementation in Common Lisp of these new methods.  相似文献   

18.
Deployment of quality-of-service (QoS) based value-added services in IP networks necessitates the use of traffic engineering. Traffic engineering allows service providers to use the network resources efficiently, according to the different quality levels associated with the range of services they offer. Traffic engineering relies typically on monitoring data for both offline proactive and dynamic reactive approaches. Monitoring data may be used for network provisioning, dynamic resource allocation, route management, and in-service performance verification for value-added IP services. A monitoring system should scale with the network size, the network speed, and the number of customers subscribed to use value-added IP services. This paper investigates the requirements of scalable monitoring system architectures, proposes principles for designing such systems and validates these principles through the design and implementation of a scalable monitoring system for traffic engineering and QoS delivery in IP Differentiated Services networks. Methods for assessing the relative merits of such monitoring systems are proposed. Experimental assessment results prove the scalability, accuracy, and also demonstrate the benefits of the proposed monitoring system.  相似文献   

19.
When interpolating incomplete data, one can choose a parametric model, or opt for a more general approach and use a non-parametric model which allows a very large class of interpolants. A popular non-parametric model for interpolating various types of data is based on regularization, which looks for an interpolant that is both close to the data and also smooth in some sense. Formally, this interpolant is obtained by minimizing an error functional which is the weighted sum of a fidelity term and a smoothness term.The classical approach to regularization is: select optimal weights (also called hyperparameters) that should be assigned to these two terms, and minimize the resulting error functional.However, using only the optimal weights does not guarantee that the chosen function will be optimal in some sense, such as the maximum likelihood criterion, or the minimal square error criterion. For that, we have to consider all possible weights.The approach suggested here is to use the full probability distribution on the space of admissible functions, as opposed to the probability induced by using a single combination of weights. The reason is as follows: the weight actually determines the probability space in which we are working. For a given weight , the probability of a function f is proportional to exp(– f2 uu du) (for the case of a function with one variable). For each different , there is a different solution to the restoration problem; denote it by f. Now, if we had known , it would not be necessary to use all the weights; however, all we are given are some noisy measurements of f, and we do not know the correct . Therefore, the mathematically correct solution is to calculate, for every , the probability that f was sampled from a space whose probability is determined by , and average the different f's weighted by these probabilities. The same argument holds for the noise variance, which is also unknown.Three basic problems are addressed is this work: Computing the MAP estimate, that is, the function f maximizing Pr(f/D) when the data D is given. This problem is reduced to a one-dimensional optimization problem. Computing the MSE estimate. This function is defined at each point x as f(x)Pr(f/D) f. This problem is reduced to computing a one-dimensional integral.In the general setting, the MAP estimate is not equal to the MSE estimate. Computing the pointwise uncertainty associated with the MSE solution. This problem is reduced to computing three one-dimensional integrals.  相似文献   

20.
The adaptiveness of agents is one of the basic conditions for the autonomy. This paper describes an approach of adaptiveness forMonitoring Cognitive Agents based on the notion of generic spaces. This notion allows the definition of virtual generic processes so that any particular actual process is then a simple configuration of the generic process, that is to say a set of values of parameters. Consequently, generic domain ontology containing the generic knowledge for solving problems concerning the generic process can be developed. This lead to the design of Generic Monitoring Cognitive Agent, a class of agent in which the whole knowledge corpus is generic. In other words, modeling a process within a generic space becomes configuring a generic process and adaptiveness becomes genericity, that is to say independence regarding technology. In this paper, we present an application of this approach on Sachem, a Generic Monitoring Cognitive Agent designed in order to help the operators in operating a blast furnace. Specifically, the NeuroGaz module of Sachem will be used to present the notion of a generic blast furnace. The adaptiveness of Sachem can then be noted through the low cost of the deployment of a Sachem instance on different blast furnaces and the ability of NeuroGaz in solving problem and learning from various top gas instrumentation.  相似文献   

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