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Data envelopment analysis (DEA) is a relative technical efficiency measurement tool, which uses operations research techniques to automatically calculate the weights assigned to the inputs and outputs of the production units being assessed. The actual input/output data values are then multiplied with the calculated weights to determine the efficiency scores. Recent variants of the DEA model impose upper and lower bounds on the weights to eliminate certain drawbacks associated with unrestricted weights. These variants are called weight restriction DEA models. Most weight restriction DEA models suffer from a drawback that the weight bound values are uncertain because they are determined based on either incomplete information or the subjective opinion of the decision-makers. Since the efficiency scores calculated by the DEA model are sensitive to the values of the bounds, the uncertainty of the bounds gets passed onto the efficiency scores. The uncertainty in the efficiency scores becomes unacceptable when we consider the fact that the DEA results are used for making important decisions like allocating funds and taking action against inefficient units. In order to minimize the effect of the uncertainty in bound values on the decision-making process, we propose to explicitly incorporate the uncertainty in the modeling process using the concepts of fuzzy set theory. Modeling the imprecision involves replacing the bound values by fuzzy numbers because fuzzy numbers can capture the intuitive conception of approximate numbers very well. Amongst the numerous types of weight restriction DEA models developed in the research, two are more commonly used in real-life applications compared to the others. Therefore, in this research, we focus on these two types of models for modeling the uncertainty in bound values. These are the absolute weight restriction DEA models and the Assurance Region (AR) DEA models. After developing the fuzzy models, we provide implementation roadmaps for illustrating the development and solution methodology of those models. We apply the fuzzy weight restriction models to the same data sets as those used by the corresponding crisp weight restriction models in the literature and compare the results using the two-sample paired t-test for means. We also use the fuzzy AR model developed in the research to measure the performance of a newspaper preprint insertion line. / Master of Science

Explains properties of mathematical sets, algebra of sets, and set order types.

This thesis is concerned with the debate between absolutists and relativists about generality. Absolutists about quantification contend that we can quantify over absolutely everything; relativists deny this. The introduction motivates and elucidates the dispute. More familiar, restrictionist versions of relativism, according to which the range of quantifiers is always subject to restriction, are distinguished from the view defended in this thesis, an expansionist version of relativism, according to which the range of quantifiers is always open to expansion. The remainder of the thesis is split into three parts. Part I focuses on generality. Chapter 2 is concerned with the semantics of quantifiers. Unlike the restrictionist, the expansionist need not disagree with the absolutist about the semantics of quantifier domain restriction. It is argued that the threat of a certain form of semantic pessimism, used as an objection against restrictionism, also arises, in some cases, for absolutism, but is avoided by expansionism. Chapter 3 is primarily engaged in a defensive project, responding to a number of objections in the literature: the objection that the relativist is unable to coherently state her view, the objection that absolute generality is needed in logic and philosophy, and the objection that relativism is unable to accommodate ‘kind generalisations’. To meet these objections, suitable schematic and modal resources are introduced and relativism is given a precise formulation. Part II concerns issues in the philosophy of mathematics pertinent to the absolutism/relativism debate. Chapter 4 draws on the modal and schematic resources introduced in the previous chapter to regiment and generalise the key argument for relativism based on the set-theoretic paradoxes. Chapter 5 argues that relativism permits a natural motivation for Zermelo-Fraenkel set theory. A new, bi-modal axiomatisation of the iterative conception of set is presented. It is argued that such a theory improves on both its non-modal and modal rivals. Part III aims to meet a thus far unfulfilled explanatory burden facing expansionist relativism. The final chapter draws on principles from metasemantics to offer a positive account of how universes of discourse may be expanded, and assesses the prospects for a novel argument for relativism on this basis.

[Truncated abstract] Fuzzy inference systems (FIS) are information processing systems using fuzzy logic mechanism to represent the human reasoning process and to make decisions based on uncertain, imprecise environments in our daily lives. Since the introduction of fuzzy set theory, fuzzy inference systems have been widely used mainly for system modeling, industrial plant control for a variety of practical applications, and also other decisionmaking purposes; advanced data analysis in medical research, risk management in business, stock market prediction in finance, data analysis in bioinformatics, and so on. Many approaches have been proposed to address the issue of automatic generation of membership functions and rules with the corresponding subsequent adjustment of them towards more satisfactory system performance. Because one of the most important factors for building high quality of FIS is the generation of the knowledge base of it, which consists of membership functions, fuzzy rules, fuzzy logic operators and other components for fuzzy calculations. The design of FIS comes from either the experience of human experts in the corresponding field of research or input and output data observations collected from operations of systems. Therefore, it is crucial to generate high quality FIS from a highly reliable design scheme to model the desired system process best. Furthermore, due to a lack of a learning property of fuzzy systems themselves most of the suggested schemes incorporate hybridization techniques towards better performance within a fuzzy system framework. ... This systematic enhancement is required to update the FIS in order to produce flexible and robust fuzzy systems for unexpected unknown inputs from real-world environments. This thesis proposes a general framework of Adaptive T-S (Takagi-Sugeno) type Rough-Fuzzy Inference Systems (ARFIS) for a variety of practical applications in order to resolve the problems mentioned above in the context of a Rough-Fuzzy hybridization scheme. Rough set theory is employed to effectively reduce the number of attributes that pertain to input variables and obtain a minimal set of decision rules based on input and output data sets. The generated rules are examined by checking their validity to use them as T-S type fuzzy rules. Using its excellent advantages in modeling non-linear systems, the T-S type fuzzy model is chosen to perform the fuzzy inference process. A T-S type fuzzy inference system is constructed by an automatic generation of membership functions and rules by the Fuzzy C-Means (FCM) clustering algorithm and the rough set approach, respectively. The generated T-S type rough-fuzzy inference system is then adjusted by the least-squares method and a conjugate gradient descent algorithm towards better performance within a fuzzy system framework. To show the viability of the proposed framework of ARFIS, the performance of ARFIS is compared with other existing approaches in a variety of practical applications; pattern classification, face recognition, and mobile robot navigation. The results are very satisfactory and competitive, and suggest the ARFIS is a suitable new framework for fuzzy inference systems by showing a better system performance with less number of attributes and rules in each application.

Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mathematics, 1979 / Vita. / Bibliography: leaves 96-98. / Ph. D. / Ph. D. Massachusetts Institute of Technology, Department of Mathematics

The specification of enterprise information systems using formal specification languages enables the formal verification of these systems. Reasoning about the properties of a formal specification is a tedious task that can be facilitated much through the use of an automated reasoner. However, set theory is a corner stone of many formal specification languages and poses demanding challenges to automated reasoners. To this end a number of heuristics has been developed to aid the Otter theorem prover in finding short proofs for set-theoretic problems. This dissertation investigates the applicability of these heuristics to next generation theorem provers. / Computing / M.Sc. (Computer Science)

Esta tese de doutorado divide-se em duas partes: a primeira trata de uma Teoria dos Conjuntos Rítmicos, e a segunda traz o Portfolio de Composições desenvolvidas no período do doutorado. A Teoria dos Conjuntos Ritmicos apresenta um sistema de organização rítmica paralelo ao sistema de organização de alturas, tendo como ponto de partida a Teoria dos Conjuntos Musicais (TCM), tal como organizada por FORTE (1973), além de uma adaptação do time-point-system (BABBITT, 1962). A partir da sistematização da TCM, e também de noções da Teoria dos Conjuntos Diatônicos (TCD), essa abordagem sintética permite estabelecer uma conexão entre aspectos básicos da harmonia e da cifragem de acordes com a organização rítmica. A um só tempo, em um catálogo completo, são relacionadas as famílias de conjuntos de alturas e cifras cordais, com suas respectivas contrapartes rítmicas. A motivação musical para esta investigação acerca dos ritmos surgiu pelo interesse nos ritmos dançantes e repetitivos, denominados timelines (TOUSSAINT, 2013), comumente utilizados na chamada música popular As timelines dançantes refletem propriedades similares às dos conjuntos diatônicos e, por essa razão, esta tese apresenta algumas propriedades dos conjuntos diatônicos de alturas, traçando um paralelo com suas contrapartes rítmicas. Essas relações também aparecem no portfolio de composições, caracterizando alguns procedimentos utilizados. O portfolio de composições, que inclui uma composição para orquestra sinfônica, é tematizado a partir da dualidade transparência/opacidade, abordando algumas diferenças essenciais, do ponto de vista da audibilidade, entre os resultados oriundos de técnicas variadas de composição. Este estudo sobre Teoria dos Conjuntos Rítmicos ajudará na abordagem analítica da minha produção composicional na música popular, trazendo uma maneira sistemática de entender e extrapolar alguns aspectos já utilizados na minha prática como compositor e improvisador. / This doctoral dissertation is divided into two parts: the first deals a rhythmic set theory, and the second contains the portfolio of compositions developed during this period of studies. This dissertation presents a system of rhythmic organization parallel to the musical set theory pitch class organization FORTE (1973), as well as an adaptation of the time-point-system (BABBITT, 1962). From the standpoint of the traditional set theory, and also from the diatonic set theory, this unified approach allows to estabilish a connecting tissue of basic aspects: from the harmony and chords symbols to the rhythmic organization. At one time, in a complete catalog, the families of pitch class sets and chord symbols are related to their respective rhythmic counterparts. The musical motivation for this research came from my interest in the swinging and groovy repetitive rhythms called timelines (TOUSSAINT, 2013), commonly used in popular music. These dancing timelines have properties similar to those of the diatonic sets, and for this reason, this dissertation presents some properties of the diatonic pitch class sets, drawing a parallel with their rhythmic counterparts. These relationships also appear in the portfolio of compositions, characterizing some procedures used. The portfolio of compositions, which includes a composition for symphony orchestra, is presented form the standpoint of a duality between transparency and opacity. This duality address the essential differences in the audibility of the results from various composition techniques. This study of Rhythmic Set Theory will serve as an analytical approach of my compositional output in popular music, with a systematic way to understant and to extrapolate some aspects already used in my practice as composer and improviser.