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In this paper we consider the location of stops along the edges of an already existing public transportation network, as introduced in [SHLW02]. This can be the introduction of bus stops along some given bus routes, or of railway stations along the tracks in a railway network. The goal is to achieve a maximal covering of given demand points with a minimal number of stops. This bicriterial problem is in general NP-hard. We present a nite dominating set yielding an IP-formulation as a bicriterial set covering problem. We use this formulation to observe that along one single straight line the bicriterial stop location problem can be solved in polynomial time and present an e cient solution approach for this case. It can be used as the basis of an algorithm tackling real-world instances.
Asymptotic homogenisation technique and two-scale convergence is used for analysis of macro-strength and fatigue durability of composites with a periodic structure under cyclic loading. The linear damage accumulation rule is employed in the phenomenological micro-durability conditions (for each component of the composite) under varying cyclic loading. Both local and non-local strength and durability conditions are analysed. The strong convergence of the strength and fatigue damage measure as the structure period tends to zero is proved and their limiting values are estimated.
In this paper we focus on the strategic design of supply chain networks. We propose a mathematical modeling framework that captures many practical aspects of network design problems simultaneously but which have not received adequate attention in the literature. The aspects considered include: dynamic planning horizon, generic supply chain network structure, external supply of materials, inventory opportunities for goods, distribution of commodities, facility configuration, availability of capital for investments, and storage limitations. Moreover, network configuration decisions concerning the gradual relocation of facilities over the planning horizon are considered. To cope with fluctuating demands, capacity expansion and reduction scenarios are also analyzed as well as modular capacity shifts. The relation of the proposed modeling framework with existing models is discussed. For problems of reasonable size we report on our computational experience with standard mathematical programming software. In particular, useful insights on the impact of various factors on network design decisions are provided.
Dieses Szenario ist eine Erweiterung eines Teilszenarios von Human Centered Manufacturing. Dabei geht es um die Montage der Energieelektrik für industrielle Anlagen. Im Jahr 2015 enthält die Ausrüstung eines Elektromonteurs bei der Verdrahtung von Schaltschränken u.a. einen Schutzhelm mit integrierter Farbkamera, integriertem Mikrofon und einem Lautsprecher im Ohrbereich sowie einen automatisch gesteuerten Laserpointer. Auf der Baustelle sind keine Pläne mehr erforderlich. Der Monteur benötigt keinen Plan während der Montage.
One of the main goals of an organization developing software is to increase the quality of the software while at the same time to decrease the costs and the duration of the development process. To achieve this, various decisions e.ecting this goal before and during the development process have to be made by the managers. One appropriate tool for decision support are simulation models of the software life cycle, which also help to understand the dynamics of the software development process. Building up a simulation model requires a mathematical description of the interactions between di.erent objects involved in the development process. Based on experimental data, techniques from the .eld of knowledge discovery can be used to quantify these interactions and to generate new process knowledge based on the analysis of the determined relationships. In this paper blocked neuronal networks and related relevance measures will be presented as an appropriate tool for quanti.cation and validation of qualitatively known dependencies in the software development process.
We consider the problem of pricing European forward starting options in the presence of stochastic volatility. By performing a change of measure using the asset price at the time of strike determination as a numeraire, we derive a closed-form solution based on Heston’s model of stochastic volatility.
We propose several algorithms for efficient Testing of logical Implication in the case of ground objects. Because the problem of Testing a set of propositional formulas for (un)satisfiability is \(NP\)-complete there's strong evidence that there exist examples for which every algorithm which solves the problem of testing for (un)satisfiability has a runtime that is exponential in the length of the input. So will have our algorithms. We will therefore point out classes of logic programs for which our algorithms have a lower runtime. At the end of this paper we will give an outline of an algorithm for theory refinement which is based on the algorithms described above.
The objective of the present article is to give an overview of an application of Fuzzy Logic in Regulation Thermography, a method of medical diagnosis support. An introduction to this method of the complementary medical science based on temperature measurements – so-called thermograms – is provided. The process of modelling the physician’s thermogram evaluation rules using the calculus of Fuzzy Logic is explained.
A non-linear multigrid solver for incompressible Navier-Stokes equations, exploiting finite volume discretization of the equations, is extended by adaptive local refinement. The multigrid is the outer iterative cycle, while the SIMPLE algorithm is used as a smoothing procedure. Error indicators are used to define the refinement subdomain. A special implementation approach is used, which allows to perform unstructured local refinement in conjunction with the finite volume discretization. The multigrid - adaptive local refinement algorithm is tested on 2D Poisson equation and further is applied to a lid-driven flows in a cavity (2D and 3D case), comparing the results with bench-mark data. The software design principles of the solver are also discussed.
This paper concerns numerical simulation of flow through oil filters. Oil filters consist of filter housing (filter box), and a porous filtering medium, which completely separates the inlet from the outlet. We discuss mathematical models, describing coupled flows in the pure liquid subregions and in the porous filter media, as well as interface conditions between them. Further, we reformulate the problem in fictitious regions method manner, and discuss peculiarities of the numerical algorithm in solving the coupled system. Next, we show numerical results, validating the model and the algorithm. Finally, we present results from simulation of 3-D oil flow through a real car filter.
In this article, we consider the problem of planning inspections and other tasks within a software development (SD) project with respect to the objectives quality (no. of defects), project duration, and costs. Based on a discrete-event simulation model of SD processes comprising the phases coding, inspection, test, and rework, we present a simplified formulation of the problem as a multiobjective optimization problem. For solving the problem (i.e. finding an approximation of the efficient set) we develop a multiobjective evolutionary algorithm. Details of the algorithm are discussed as well as results of its application to sample problems.
In this paper, we present a novel multicriteria decision support system (MCDSS), called knowCube, consisting of components for knowledge organization, generation, and navigation. Knowledge organization rests upon a database for managing qualitative and quantitative criteria, together with add-on information. Knowledge generation serves filling the database via e.g. identification, optimization, classification or simulation. For “finding needles in haycocks”, the knowledge navigation component supports graphical database retrieval and interactive, goal-oriented problem solving. Navigation “helpers” are, for instance, cascading criteria aggregations, modifiable metrics, ergonomic interfaces, and customizable visualizations. Examples from real-life projects, e.g. in industrial engineering and in the life sciences, illustrate the application of our MCDSS.
Las matemáticas son atribuidas en general a algo no claro y sólo para matemáticos. La imagen de las matemáticas para los escolares, es la de una ciencia, la cual se sirve sólo de si misma. Es importante hacer frente al prejuicio de que las matemáticas distan lejos de toda utilidad práctica. La matemática es una ciencia al servicio de todas las dem´as ciencias, de cuya ayuda se necesita en casi todos los campos de la vida. La matemática de la escuela debería despertar en cualquier ámbito de la vida de los escolares el interés sobre ...
Linear Optimization is an important area from applied mathematics. A lot of practical problems can be modelled and solved with this technique. This publication shall help to introduce this topic to pupils. The process of modelling, the reduction of problems to their significant attributes shall be described. The linear programms will be solved by using the simplex method. Many examples illustrate the topic.
Industrial analog circuits are usually designed using numerical simulation tools. To obtain a deeper circuit understanding, symbolic analysis techniques can additionally be applied. Approximation methods which reduce the complexity of symbolic expressions are needed in order to handle industrial-sized problems. This paper will give an overview to the field of symbolic analog circuit analysis. Starting with a motivation, the state-of-the-art simplification algorithms for linear as well as for nonlinear circuits are presented. The basic ideas behind the different techniques are described, whereas the technical details can be found in the cited references. Finally, the application of linear and nonlinear symbolic analysis will be shown on two example circuits.
Unter Ambient Intelligence (AmI) wird die Integration verschiedener Technologien zu einer den Menschen umgebenden, (nahezu) unsichtbaren Gesamtheit verstanden. Diese Intelligente Umgebung wird möglich durch die Miniaturisierung hochintegrierter Bauteile (Sensoren, Aktuatoren und Rechnern), deren zunehmende Intelligenz und vor allem deren lokale und globale zunehmend drahtlose Vernetzung. Unter dem Titel Man-u-Faktur 2012 (man and factoring in 2012) wurde an der Technischen Universität Kaiserslautern im Rahmen des Forschungsschwerpunkts Ambient Intelligence ein Szenario entwickelt, das ein beeindruckendes Gesamtbild einer Technik, die den Menschen in den Mittelpunkt rückt, beschreibt. Man-u-Faktur 2012 steht dabei für ein Weiterdrehen des Rads der Industrialisierung von der heute üblichen variantenreichen, technologiezentrierten Massenfertigung hin zu einer kundenindividuellen, mitarbeiterzentrierten Maßfertigung. Im Speziellen wird hierunter der Aufbau massiv verteiler kunden- aber auch mitarbeiterfreundlicher Produktionsanlagen verstanden, die sich im hochdynamischen Umfeld entsprechend der jeweiligen Gegebenheiten anzupassen wissen. Der Mensch ist überall dort präsent, wo flexibles Arbeiten oder flexible Entscheidungen im Vordergrund stehen. In diesem Bericht wird der Einfluss von Ambient Intelligence beispielhaft auf die Vision einer Fahrradproduktion in der Man-u-Faktur 2012 angewandt. Aus diesem Szenario werden anschließend sowohl die zu entwickelnden Schlüsseltechnologien als auch die Einflüsse auf Wirtschaft und Gesellschaft abgeleitet.
UML and SDL are languages for the development of software systems that have different origins, and have evolved separately for many years. Recently, it can be observed that OMG and ITU, the standardisation bodies responsible for UML and SDL, respectively, are making efforts to harmonise these languages. So far, harmonisation takes place mainly on a conceptual level, by extending and aligning the set of language concepts. In this paper, we argue that harmonisation of languages can be approached both from a syntactic and semantic perspective. We show how a common syntactical basis can be derived from the analysis of the UML meta-model
and the SDL abstract grammar. For this purpose, conceptually sound and well-founded mappings from meta-models to abstract grammars and vice versa are defined and applied. On the semantic level, a comparison between corresponding language constructs is performed.