DOI: 10.3897/jucs.146407

Authors: Zhichao Chen, Zixi Han, Bingqing Shen, Yuxin Zeng, Min Wang, Hongming Cai, Minqi Wang

Abstract: Abstract: The Integrated Process Planning and Scheduling (IPPS) problem has long been a practical concern in industry, with numerous problem modelling and solving methods to optimize multiple objectives, such as makespan and cost. As yet, existing modelling methods have difficulties in satisfying new modelling requirements for adequately representing real complex manufacturing jobs. This paper proposes a novel computing framework for modelling and solving complex IPPS problems based on a Supplier-Input-Process-yield-Output-Customer-Resource-Control (called SIPyOC-RC) model. This framework includes a SIPyOC-RC modelling method to address the modelling adequacy problem. With the proposed method, complex IPPS problems in real manufacturing scenarios, such as commercial airplane component production and assembly, can be modeled with the key demanding features. Next, the SIPyOC-RC model can be transformed into a Constraint Programming (CP) model, which can then be solved with any CP-solver. Based on an implemented testbed, the modelling adequacy and computation performance of the proposed approach has been evaluated. The experiment results show that it can successfully solve complex IPPS problems without significant computation cost. Moreover, its compatibility with conventional IPPS problems is also discussed. Overall, the outcome of this study contributes both theoretical methodology and practical experience to industrial computing.

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DOI: 10.3217/jucs-022-11-1437

Authors: Vladimir Ciric, Aleksandar Cvetkovic, Ivan Milentijevic, Oliver Vojinovic

Abstract: Motivated by the large number of vertices that future technologies will put in the front of path-search algorithms, and inspired by highly regular 2D mesh structures that exist in the domain applications, in this paper we propose a new allpairs shortest paths algorithm, for any given regular 2D mesh topology, with complexity Ο(|V|2), where |V| is the number of vertices in the graph. The proposed algorithm can achieve better runtime than other known algorithms at the cost of narrowing the scope of the graphs that it can process to the graphs with regular 2D topology. The algorithm is developed into formalism by algebraic transformations in tropical algebra of the well-known Floyd-Warshall's algorithm. First we prove the equivalency of the Floyd-Warshall's algorithm and its tropical algebraic representation, and put the transformations of the algorithm into the algebraic domain. Secondly, having in mind the structure of the target class of graphs, we transform the original algorithm in the algebraic domain and develop a simple, low-complexity iterative algorithm for all-pairs shortest paths calculation. Decreasing of computational complexity can contribute to better exploitation of the algorithm in the wide range of applications from hardware design in new emerging technologies to big data problems in information technologies.

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DOI: 10.3217/jucs-014-20-3282

Authors: Irène Durand, Sylviane Schwer

Abstract: Reasoning about incomplete qualitative temporal information is an essential topic inmany artificial intelligence and natural language processing applications. In the domain of natural language processing for instance, the temporal analysis of a text yields a set of temporal relationsbetween events in a given linguistic theory. The problem is first to express events and any possible temporal relations between them, then to express the qualitative temporal constraints (as subsetsof the set of all possible temporal relations) and compute (or count) all possible temporal relations that can be deduced. For this purpose, we propose to use the formalism of S-languages, based onthe mathematical notion of S-arrangements with repetitions [Schwer, 2002]. In this paper, we present this formalism in detail and our implementation of it. We explain why Lisp is adequateto implement this theory. Next we describe a Common Lisp system SLS (for S-LanguageS)which implements part of this formalism. A graphical interface written using McCLIM, the free implementation of the CLIM specification, frees the potential user of any Lisp knowledge. Fullydeveloped examples illustrate both the theory and the implementation.

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DOI: 10.3217/jucs-008-08-0793

Authors: Sylviane Schwer

Abstract: The formalizations of periods of time inside a linear model of Time are usually based on the notion of intervals, that may contain or may not their endpoints. This is not enough when the periods are written in terms of coarse granularities with respect to the event taken into account. For instance, how to express the inter-war period in terms of a years interval? This paper presents a new type of intervals, neither open, nor closed or open-closed and the extension of operations on intervals of this new type, in order to reduce the gap between the discourse related to temporal relationship and its translation into a discretized model of Time.

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DOI: 10.3217/jucs-007-02-0124

Authors: Alessandro Armando, Silvio Ranise

Abstract: In this paper, we propose a generic mechanism for extending decision procedures by means of a lemma speculation mechanism. This problem is important in order to widen the scope of decision procedures incorporated in state-of-the-art verification systems. Soundness and termination of the extension schema are formally stated and proved. As a case study, we consider extensions of a decision procedure for the quantifier-free fragment of Presburger Arithmetic to significant fragments of non-linear arithmetic.

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DOI: 10.3217/jucs-004-01-0048

Authors: Evgenija Popova

Abstract: The arithmetic on the extended set of proper and improper intervals is an algebraic completion of the conventional interval arithmetic and thus facilitates the explicit solution of certain interval algebraic problems. Due to the existence of inverse elements with respect to addition and multiplication operations certain interval algebraic equations can be solved by elementary algebraic transformations. The conditionally distributive relations between extended intervals allow that complicated interval algebraic equations, multi-incident on the unknown variable, be reduced to simpler ones. In this paper we give the general type of "pseudo-linear" interval equations in the extended interval arithmetic. The algebraic solutions to a pseudo-linear interval equation in one variable are studied. All numeric and parametric algebraic solutions, as well as the conditions for nonexistence of the algebraic solution to some basic types pseudo-linear interval equations in one variable are found. Some examples leading to algebraic solution of the equations under consideration and the extra func- tionalities for performing true symbolic-algebraic manipulations on interval formulae in a Mathematica package are discussed.

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DOI: 10.3217/jucs-002-02-0058

Authors: Svetoslav Markov, Y. Akyildiz

Abstract: This paper is devoted to the software implementation of two mathematical methods which are often used in biological applications: interpolation and curve fitting in the presence of uncertainties in the input data given in the form of intervals. The methods involve model functions linear in their parameters and are formulated by means of simple expressions in terms of interval arithmetic allowing the computation of verified bounds for the interpolating/approximating functions. The methods are demonstrated for certain classes of nonlinear modelling functions finding applications in biology. A case study involving enzyme-catalysed reaction is considered. The numerical results are performed in the computer algebra system Mathematica, which supports interval-arithmetic computations.

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DOI: 10.3217/jucs-001-07-0514

Authors: Svetoslav Markov

Abstract: We discuss two closely related interval arithmetic systems: i) the of directed (generalized) intervals studied by E. Kaucher, and ii) the syste intervals together with the outer and inner interval operations. A relation two systems becomes feasible due to introduction of special notations and a normal form of directed intervals. As an application, it has been shown that interval systems can be used for the computation of tight inner and outer in of ranges of functions and consequently for the development of software for computation of ranges of functions.

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