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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

Prikry-Forcing und einige Verallgemeinerungen

Löffelmann, Jochen. January 1900 (has links)
Thesis (doctoral)--Rheinische Friedrich-Wilhelms-Universität Bonn, 2001. / Includes bibliographical references (p. 107-109).
332

Topics in the model theory of set theory

Enayat, Ali. January 1983 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1984. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 91-94).
333

Model theory of probability logic

Hoover, Douglas Neil. January 1978 (has links)
Thesis--Wisconsin. / Vita. Includes bibliographical references (leaves 98-99).
334

Dynamics of Heisenberg spin chains

Hagemans, Robert Lambertus. January 1900 (has links)
Proefschrift Universiteit van Amsterdam. / Met lit.opg. en samenvatting in het Nederlands.
335

A Single-Product Inventory Model for Multiple Demand Classes

Arslan, Hasan, Graves, Stephen C., Roemer, Thomas 27 May 2005 (has links)
We consider a single-product inventory system that serves multiple demand classes, which differ in their shortage costs or service level requirements. We assume a critical-level control policy, and show the equivalence between this inventory system and a serial inventory system. Based on this equivalence, we develop a model for cost evaluation and optimization, under the assumptions of Poisson demand, deterministic replenishment lead-time, and a continuous-review (Q, R) policy with rationing. We propose a computationally-efficient heuristic and develop a bound on its performance. We provide a numerical experiment to show the effectiveness of the heuristic and the value from a rationing policy. Finally, we describe how to extend the model to permit service times, and to embed within a multi-echelon setting.
336

Estudo de um modelo dinâmico para avaliação física do corpo humano

Russi, Pedro Carlos [UNESP] 12 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-12Bitstream added on 2014-06-13T19:37:21Z : No. of bitstreams: 1 russi_pc_me_guara.pdf: 338766 bytes, checksum: 6a00ac32d9ca90d3359a4343b50c03b0 (MD5) / O problema da modelagem da locomoção humana tem atraído a atenção de pesquisadores por muitos anos. A compreensão, análise e avaliação da marcha humana oferecem dados importantes para o uso de próteses dos membros inferiores. O objetivo deste trabalho é apresentar um modelo matemático da marcha humana, através de um modelo simplificado do corpo humano para que sirva de referência no trabalho de adaptação ao uso de próteses. O desenvolvimento da modelagem, parte da geometria dos membros inferiores num sistema de referência bidimensional e utiliza o princípio da diferença entre as energias cinética e potencial do sistema, ou seja, o método de Lagrange, introduzido na forma matricial. O modelo é representado na fase de oscilação, por dois segmentos interconectados com massas concentradas que oscila como um pêndulo duplo. Na fase de apoio é representado por três segmentos interconectados com massas concentradas que se movimenta como um pêndulo triplo invertido. Obtidas as equações que representam o modelo, os torques nas articulações do tornozelo, joelho e quadril são obtidos e a simulação numérica é realizada no programa MATLAB. Os resultados dos torques calculados apresentaram coerências com os da literatura, porém, na fase de apoio diferenças significativas foram registradas. / The problem of human locomotion modeling has been attracting the researcher attention for many years. The understanding, analysis and evaluation of the human locomotion provide important data for the use of prostheses in the inferior parts of the body. The aim of this issue is to present a mathematical model of the human locomotion through a simplified model of the human body so that it serves as reference in the adaptation for prostheses usage. The modeling was developed using the geometry of the inferior parts of the body in a system of bidimensional references and applies the principle of difference between kinetic energies and potential of the system, in other words, the method of Lagrange, introduced in the form matrix. The model is represented in the oscillation phase, for two segments interconnected with concentrated masses which oscillates as a double pendulum. In the support phase it is represented in three segments interconnected with concentrated masses which move as an inverted triple pendulum. Since the equations representing the model are provided, the torque in the articulations of the ankle, knee and hip are obtained and the numeric simulation is accomplished in the program MATLAB. The results of the calculated torque showed coherence with the one of the literature, however, in the support phase the significant differences were registered.
337

Normalisation techniques in proof theory and category theory

Hamza, Taher Tawfik Ahmed January 1986 (has links)
The word problem for the free categories with some structure generated by a category X can be solved using proof-theoretical means. These free categories give a semantics in which derivations of GENTZEN's propositional sequent calculus can be interpreted by means of arrows of those categories. In this thesis we describe, implement and document the cut-elimination and the normalization techniques in proof theory as outlined in SZABO [1978]: we show how these are used in order to solve, mechanically, the word problem for the free categories with structure of : cartesian, bicartesian, distributive bicartesian, cartesian closed, and bicartesian closed. This implementation is extended by a procedure to interpret intuitionistic propositional sequent derivations as arrows of the above categories. Implementation of those techniques has forced us to modify the techniques in various inessential ways. The description and the representation in the syntax of our implementation of the above categories is contained in chapters 1 - 5, where each chapter describes one theory and concludes with examples of the system In use to represent concepts and solve simple word problems from category theory ( of various typos ). Appendix 1 contains some apparent printing errors we have observed in the work done by SZABO. The algorithms used in the proof of the cut-elimination theorems and normalization through chapters 1 - 5 are collected in appendices 2 - 4. Appendices 5 - 8 concern the implementation and its user manual.
338

The hospitalist model: remedy or new problem for a rapidly changing system?

Sanders, Jennifer January 2006 (has links)
Boston University. University Professors Program Senior theses. / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / 2031-01-02
339

Simplifying Process Model Abstraction: Techniques for Generating Model Names

Leopold, Henrik, Mendling, Jan, Reijers, Hajo A., La Rosa, Marcello 01 1900 (has links) (PDF)
The increased adoption of business process management approaches, tools, and practices has led organizations to accumulate large collections of business process models. These collections can easily include from a hundred to a thousand models, especially in the context of multinational corporations or as a result of organizational mergers and acquisitions. A concrete problem is thus how to maintain these large repositories in such a way that their complexity does not hamper their practical usefulness as a means to describe and communicate business operations. This paper proposes a technique to automatically infer suitable names for business process models and fragments thereof. This technique is useful for model abstraction scenarios, as for instance when user-specific views of a repository are required, or as part of a refactoring initiative aimed to simplify the repository's complexity. The technique is grounded in an adaptation of the theory of meaning to the realm of business process models. We implemented the technique in a prototype tool and conducted an extensive evaluation using three process model collections from practice and a case study involving process modelers with different experience.
340

Towards a spatial energy model : a theoretical comparison of accessibility and energy-use in regional settlement patterns

Rickaby, P. January 1985 (has links)
The research reported is a theoretical investigation of the interaction of land-use and transport in relation to the use of energy. Of particular interest is the relationship between the spatial arrangement of settlements and the use of energy within them for both transport and building services. The literature of scenarios of energy futures is reviewed, and three scenarios of future constraints on regional planning are adopted. The adopted scenarios emphasise constraints imposed by energy policy and the availability of fuels; they form the background to the comparison of a number of theoretical regional settlement patterns, in terms of their implications for land-use and their potential for fuel-conservation. A study of an existing regional settlement pattern is used in combination with published land-use data as the basis of a configurational model. This model is intended to characterise the real pattern spatially, quantitatively and in a manner suitable for experimental manipulation. The model encompasses the pattern of developed land (disaggregated by uses), the shape of the transport network, and the intensity of development (in terms of population and floorspace). A review is then made of published proposals for energy-efficient settlements, which are found to include concentrated, dispersed, nucleated and linear patterns. Five modified versions of the regional configurational model are then constructed in order to characterise the range of realistic possibilities for future regional form which might result from the fuel-conservation policies inherent in the proposals reviewed. The five regional configurations and the original pattern are then compared by means of a specially-developed land-use transport and energy-evaluation model. The comparison is made in terms of the accessibility of the population in each pattern to employment and services (measured 'biy the model as "benefits"), and. in terms of the use of fuel in both transport and domestic space heating. Fuel use in transport is related to modal split and vehicle speed; fuel use in homes is related to dwelling size and location. Parametric calibration of the land-use and transport models allows the comparison of the patterns to be repeated in the context of each of the three adopted energy scenarios, taking into account changes in travelling behaviour, vehicle efficiencies, and building services technologies. The results of the comparison are discussed and assessed in terms of their implications for long-term strategic planning policy.

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