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Objective assessment of the neonatal outcome of labour is important, but it is a difficult and challenging problem. It is an invaluable source of information which can be used to provide feedback to clinicians, to audit a unit's overall performance, and can guide subsequent neonatal care. Current methods are inadequate as they fail to distinguish damage that occurred during labour from damage that occurred before or after labour. Analysis of the chemical acid-base status of blood taken from the umbilical cord of an infant immediately after delivery provides information on any damage suffered by the infant due to lack of oxygen during labour. However, this process is complex and error prone, and requires expertise which is not always available on labour wards. A model of clinical expertise required for the accurate interpretation of umbilical acid-base status was developed, and encapsulated in a rule-based expert system. This expert system checks results to ensure their consistency, identifies whether the results come from arterial or venous vessels, and then produces an interpretation of their meaning. This 'crisp' expert system was validated, verified and commercially released, and has since been installed at twenty two hospitals all around the United Kingdom. The assessment of umbilical acid-base status is characterised by uncertainty in both the basic data and the knowledge required for its interpretation. Fuzzy logic provides a technique for representing both these forms of uncertainty in a single framework. A 'preliminary' fuzzy-logic based expert system to interpret error-free results was developed, based on the knowledge embedded in the crisp expert system. Its performance was compared against clinicians in a validation test, but initially its performance was found to be poor in comparison with the clinicians and inferior to the crisp expert system. An automatic tuning algorithm was developed to modify the behaviour of the fuzzy model utilised in the expert system. Sub-normal membership functions were used to weight terms in the fuzzy expert system in a novel manner. This resulted in an improvement in the performance of the fuzzy expert system to a level comparable to the clinicians, and superior to the crisp expert system. Experimental work was carried out to evaluate the imprecision in umbilical cord acid-base parameters. This information, in conjunction with fresh knowledge elicitation sessions, allowed the creation of a more comprehensive fuzzy expert system, to validate and interpret all acid-base data. This 'integrated' fuzzy expert system was tuned using the comparison data obtained previously, and incorporated vessel identification rules and interpretation rules, with numeric and linguistic outputs for each. The performance of each of the outputs was evaluated in a rigorous validation study. This demonstrated excellent agreement with the experts for the numeric outputs, and agreement on a par with the experts for the linguistic outputs. The numeric interpretation produced by the fuzzy expert system is a novel single dimensional measure that accurately represents the severity of acid-base results. The development of the crisp and fuzzy expert systems represents a major achievement and constitutes a significant contribution to the assessment of neonatal outcome.

The GUHA method is one of the oldest methods of exploratory data analysis, which is regarded as part of the data mining or knowledge discovery in databases (KDD) scienti_c area. Unlike many other methods of data mining, the GUHA method has firm theoretical foundations in logic and statistics. In scope of the method, finding interesting knowledge corresponds to finding special formulas in satisfactory rich logical calculus, which is called observational calculus. The main topic of the thesis is application of the "fuzzy paradigm" to the GUHA method By the term "fuzzy paradigm" we mean approaches that use many-valued membership degrees or truth values, namely fuzzy set theory and fuzzy logic. The thesis does not aim to cover all the aspects of this application, it emphasises mainly on: - Association rules as the most prevalent type of formulas mined by the GUHA method - Usage of fuzzy data - Logical aspects of fuzzy association rules mining - Comparison of the GUHA theory to the mainstream fuzzy association rules - Implementation of the theory using the bit string approach The thesis throughoutly elaborates the theory of fuzzy association rules, both using the theoretical apparatus of fuzzy set theory and fuzzy logic. Fuzzy set theory is used mainly to compare the GUHA method to existing mainstream approaches to formalize fuzzy association rules, which were studied in detail. Fuzzy logic is used to define novel class of logical calculi called logical calculi of fuzzy association rules (LCFAR) for logical representation of fuzzy association rules. The problem of existence of deduction rules in LCFAR is dealt in depth. Suitable part of the proposed theory is implemented in the Ferda system using the bit string approach. In the approach, characteristics of examined objects are represented as strings of bits, which in the crisp case enables efficient computation. In order to maintain this feature also in the fuzzy case, a profound low level testing of data structures and algoritms for fuzzy bit strings have been carried out as a part of the thesis.

A thesis submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements of the degree of Doctor of Philosophy. Johannesburg, February 2017 / Rainwater harvesting is used as a way of improving crop yields in rain fed agriculture by capturing excess rainfall and storing it in-situ or in reservoirs for use during dry spells. Contour ridges are one of the many rainwater harvesting technologies that are used although little is known about their effectiveness. Contour ridges harvest runoff generated in the cropped field upstream of the ridges. The traditional contour ridge type in Zimbabwe was introduced by the government in the 1950s to control soil erosion through safely draining away runoff from cropped fields and is commonly referred to as graded contour (GC) ridges. In the 1990s the country experienced severe and more frequent droughts leading stakeholders to experiment on contour ridges that retain the runoff instead of draining it away which are known as dead level contour (DLC) ridges. There was therefore the need to find out if there are benefits derived from this change and assess conditions under which benefits would be experienced. Previous studies have shown that rainwater harvested by contour ridges can improve water availability in downstream fields. However these studies did not investigate the conditions under which such benefits are realised. In addition no attempt to model water harvesting by contour ridges have been made in Zimbabwe while the contour ridges are widely being used for soil and water conservation. This research investigated the effect of contour ridges by comparing soil moisture between plots with DLC and GC ridges using plots with no contours as a control. Experimental work was carried out in Zhulube, in Matebeleland South Province of Zimbabwe. Matebeleland South Province falls within the semi-arid area in which rainfall is characterised by mid-season dry spells leading to frequent crop failure. In addition, the area often receives high rainfall intensities leading to soil erosion and sedimentation of rivers. DLC and GC ridges were constructed in farmers’ fields where maize crops were planted. Soil moisture measurements were done using a micro gopher soil moisture profiler while runoff plots were used to measure runoff generation. A fuzzy model was developed using data from this experiment and a previous study in Masvingo Province of Zimbabwe to simulate runoff generation at field scale while a process based water balance model was also developed to simulate soil moisture changes within the root zone of the cropped area. The results from this study indicate that DLC are effective in clay and loamy soils where runoff generation is significant and not in sandy soils due to insignificant generation of runoff under the rainfall regimes of semi-arid areas. Fuzzy logic was found to be a useful method of incorporating uncertainty in modelling runoff at field scale. A mass water balance model developed on process based principles was able to model soil moisture in the root zone reasonably well (NSE =0.55 to 0.66 and PBIAS=-1.3% to 6.1%) and could help to predict the water dynamics in contour ridged areas as would be required in determining the suitable dimensions and spacing of contour ridges. Further research is required to improve the fuzzy component of the model for estimation of runoff when more data becomes available. In addition experiments to validate methods of estimating macro pore fluxes and lateral transfer of water from the contour ridge channel to the downslope field are also recommended. The model structure can be improved by adopting the representative elementary watershed approaches to include momentum and energy balances in addition to mass balance that was used in this study. / MT2017

Submitted by Aline Batista (alinehb.ufpel@gmail.com) on 2018-04-18T14:21:35Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Rosana_Medina_Zanotelli.pdf: 897398 bytes, checksum: 53b6f15a010386648223058dfc32101b (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-04-19T14:42:08Z (GMT) No. of bitstreams: 2 Dissertacao_Rosana_Medina_Zanotelli.pdf: 897398 bytes, checksum: 53b6f15a010386648223058dfc32101b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-04-19T14:42:21Z (GMT). No. of bitstreams: 2 Dissertacao_Rosana_Medina_Zanotelli.pdf: 897398 bytes, checksum: 53b6f15a010386648223058dfc32101b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-04-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Esta dissertação contribui com a análise da robustez na Lógica Fuzzy, como uma importante fundamentação para modelagem e desenvolvimento de sistemas robustos, estendendo esta abordagem para a lógica intuicionista de Atanassov. Primeiramente, apresenta-se uma introdução à lógica fuzzy, discutindo as negações, funções de agregações, implicações e coimplicações fuzzy, incluindo também os conectivos Xor e derivações. O trabalho também considera a análise da -sensibilidade destes conectivos fuzzy e suas construções duais, essencialmente focados em propriedades algébricas e projeções. Começando com a avaliação da sensibilidade de conectivos fuzzy, a proposta estende os resultados para classes de conectivos fuzzy intuicionistas. Como principal contribuição, formalmente estabelece-se que a robustez preserva as construções duais e as funções de projeção relacionadas a conectivos fuzzy intuicionistas representáveis. Mostra-se que a extensão, do trabalho científico proposto por Y. Li e colaboradores, 2005 em "An Approach to Measure the Robustness of Fuzzy Reasoning", para a classe de conectivos fuzzy intuicionistas é preservada pelas construções duais. A presente pesquisa mostra que a análise de robustez pode ser diretamente verificada a partir de operadores fuzzy usando duas estratégias: (i) a -sensibilidade de operadores fuzzy baseada na análise da monotonicidade de seus argumentos (negações, agregações, implicações e coimplicações); e ainda (ii) a avaliação do comportamento dos operadores fuzzy nos pontos terminais do intervalo unitário, onde a monotonicidade não pode ser aplicada (conectivos Xor, XNor, bi-implicações e bi-coimplicações). / This dissertation contributes to the robustness analysis in fuzzy logic as an important founding for modeling and developing robust systems, extending such approach to the Atanassov’s intuitionistic fuzzy sets. It begins with the introduction of fuzzy logic, discussing negations, aggregation functions, fuzzy implications and bi-implications, also including Xor connectives and derivations. It also considers the -sensitivity analysis of these fuzzy connectives and their dual constructions from a few essentials such as properties and projections. Starting with an evaluation of the sensitivity in representable fuzzy connectives, the results are applied in the intuitionistic connective classes. The main result formally states that the robustness preserves the projection functions of representable intuitionistic fuzzy connectives. It shows an extension of the work in Y. Li et al, 2005 "An Approach to Measure the Robustness of Fuzzy Reasoning" for the class of intuitionistic fuzzy connectives, showing that the robustness of intuitionistic fuzzy sensitivity is preserved by dual constructions. The present research states that robustness analysis of intuitionistic fuzzy operators can be directly verified from fuzzy operators using two strategies: (i) the -sensitivity analysis of fuzzy connectives based on monotonicity of their arguments (negations, aggregations, implications and coimplications); and, otherwise (ii) the evaluation of the behaviour related to fuzzy connectives in endpoints of the unit interval, when the monotonicity property is not applied (Xor, XNor, bi-implications e bi-coimplications fuzzy operators).

Submitted by Aline Batista (alinehb.ufpel@gmail.com) on 2018-04-18T14:30:20Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Alex_Bertei.pdf: 2631033 bytes, checksum: 64d9253595f75230a7d83432fb89d6e9 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-04-19T14:42:33Z (GMT) No. of bitstreams: 2 Dissertacao_Alex_Bertei.pdf: 2631033 bytes, checksum: 64d9253595f75230a7d83432fb89d6e9 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-04-19T14:42:41Z (GMT). No. of bitstreams: 2 Dissertacao_Alex_Bertei.pdf: 2631033 bytes, checksum: 64d9253595f75230a7d83432fb89d6e9 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Com o passar dos dias os sistemas de software e hardware evoluem e ficam cada vez mais complexos e sofisticados. Como consequência especificar esses sistemas se torna uma tarefa difícil e trabalhosa. No sentido de assegurar certas propriedades de um sistema, este deve ser especificado por intermédio de uma linguagem que ofereça métodos de análise. Para realizar essas especificações temos diversas técnicas e metodologias, onde algumas técnicas que são disponíveis no mercado podem gerar resultados diferentes do que o especificado e esperado. Para realizar a correção deste problema, tem-se a necessidade de se utilizar métodos formais para gerar a especificação e verificação de sistemas. Sistemas que utilizam métodos formais são especificados formalmente através de um modelo matemático. Gramática de Grafos é uma linguagem formal bastante propícia para especificar sistemas complexos, é interessante o uso delas, pelo fato de possuírem inúmeras técnicas para a verificação e especificação de sistemas que são representadas nesta linguagem, além do que, elas possuem um layout gráfico, que as torna bastante intuitivas, por isso elas são uma linguagem de fácil entendimento. Gramática de Grafos Fuzzy são obtidas através da generalização das gramáticas de grafos, elas são constituídas por vértices e arestas com valores de pertinência associados, dentro do intervalo 0 e 1. Devido a inexistência de técnicas e ferramentas de análise para gramática de grafos fuzzy, o seu uso ainda é bastante restrito. Uma maneira de permitir a análise de sistemas especificados em gramática de grafos fuzzy é através da extensão das abordagens existentes para gramática de grafos, adicionando os conceitos de pertinência aos componentes dos grafos e para isso foi necessário definir gramáticas de grafos fuzzy tipados. Já existe uma abordagem relacional para gramática de grafos que permite o uso dos provadores de teoremas da ferramenta Rodin, utilizando a linguagem Event-B. Desta forma, a proposta deste trabalho é estender essa abordagem de gramática de grafos adicionando os conceitos fuzzy para permitir utilizar a mesma abordagem para analisar gramática de grafos fuzzy, surgindo assim um método de análise para esse tipo de gramática. / With the passing of days software and hardware systems evolve and become increasingly sophisticated and complex. As a consequence, specifying these systems becomes a difficult and laborious task. In order to ensure certain properties of a system, it must be specified through a language that offers methods of analysis. To realize these specifications we have several techniques and methodologies, where some techniques that are available in the market can generate different results than the specified and expected. To perform the correction of this problem, there is the need of using formal methods for generate the specification and verification systems. Systems that use formal methods are formally specified through a mathematical model. Grammar Graphs is a very suitable to specify complex systems formal language, is interesting to use them because they have innumerable techniques for the verification and specification of systems that are represented in this language, besides that, they have a graphical layout, which makes them very intuitive, so they are an easy-to-understand language. Fuzzy graph grammars are obtained through the generalization of graph grammars, they are constituted by vertices and edges with associated membership values within the interval 0 and 1. Due to the inexistence of techniques and analysis tools for fuzzy graph grammars, its use is still quite restricted. One way to allow the analysis of systems specified in fuzzy graphs grammars is the extension of existing approaches for graphs grammars, adding the concepts of pertinence to the components of graphs and for this it was necessary to define fuzzy graph grammars typed. There is already a relational approach to graph grammar that allows the use of the theorems of the Rodin tool using the language Event-B. In this way, the purpose of this work is to extend this approach of grammars of graphs by adding the fuzzy concepts to allow to use the same approach to analyze fuzzy graphs grammars, thus appearing a method of analysis for this type of grammar.