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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.
91

Modeling Concurrency with Interval Traces

Yin, Xiang 11 1900 (has links)
When system runs are modeled with interval orders, interval order structures are useful tools to model abstract concurrent histories, i.e. sets of equivalent system runs. For the general cases, Mazurkiewicz traces allow a representation of the entire partial order by a single sequence with independency relations, and Comtraces allow a representation of stratified order structures by single step sequences with appropriate simultaneity and serializability relations. Unfortunately, both of them are unable to clearly describe the abstract interval order semantics of inhibitor nets. The goal of the thesis is to provide a monoid based model called Interval Traces that would allow a single sequence of beginnings and endings to represent the entire stratified order structures as well as all equivalent interval order observations. And the thesis will also show how interval order structures can be modelled by interval traces and how interval traces can be used to describe interval order semantics. / Thesis / Doctor of Philosophy (PhD)
92

UNCERTAINTIES IN THE SOLUTIONS TO BOUNDARY ELEMENT METHOD: AN INTERVAL APPROACH

Zalewski, Bartlomiej Franciszek 04 June 2008 (has links)
No description available.
93

Molecular Signalling Responses to High-Intensity Interval Exercise: Effects of Carbohydrate Availability / Molecular Signalling Responses to High-Intensity Interval Exercise

Cochran, Andrew 09 1900 (has links)
This thesis is missing page 63 from all copies. -Digitization Centre / Manipulating carbohydrate (CHO) availability has been shown to alter acute exercise-induced changes in metabolic gene transcription and training-induced changes in oxidative capacity. The present study examined the effect of CHO availability on signalling pathways linked to mitochondrial biogenesis in response to high-intensity interval exercise (HIE). We hypothesized that reduced CHO availability would augment phosphorylation of AMP-activated protein kinase (AMPK), calcium/calmodulin-dependent kinase II (CaMKII), and p38 mitogen-activated protein kinase (p38) in response to HIE. Ten active men performed two experimental trials in random order, separated by 2:1 wk. During each trial, subjects performed two HIE sessions separated by 3 h (AM and PM sessions). Exercise sessions consisted of 5 x 4 min cycling bouts at a workload that elicited approximately 90% V02peak, with 2 min rest periods. Between sessions, subjects ingested -1.2 g CHO/kg b.w./h (HI-HI) or a taste-matched, non-energetic placebo (HI-LO). Muscle biopsies and blood samples were obtained before (Pre) and after (Post) the AM and PM HIE sessions. AMPK, CaMKII, and p38 MAPK phosphorylation increased from AM Pre to AM Post (p<0.01). During the PM exercise session, p38 phosphorylation increased in the HI-LO condition (-4.5-fold, p<0.001), whereas the HI-HI condition remained unchanged. PM HIE significantly increased CaMKII phosphorylation independent of condition, while no exercise or condition-mediated AMPK effects were observed. In summary, restricting CHO availability following an acute session of HIE augmented the exercise-induced increase in p38 phosphorylation during a subsequent HIE session. It remains to be determined whether chronic changes in p38 MAPK signalling are mechanistically linked to altered skeletal muscle remodelling observed after CHO-restricted exercise training. / Thesis / Master of Science (MS)
94

Intervalové lineární a nelineární systémy / Interval linear and nonlinear systems

Horáček, Jaroslav January 2019 (has links)
First, basic aspects of interval analysis, roles of intervals and their applications are addressed. Then, various classes of interval matrices are described and their relations are depicted. This material forms a prelude to the unifying theme of the rest of the work - solving interval linear systems. Several methods for enclosing the solution set of square and overdetermined interval linear systems are covered and compared. For square systems the new shaving method is introduced, for overdetermined systems the new subsquares approach is introduced. Detecting unsolvability and solvability of such systems is discussed and several polynomial conditions are compared. Two strongest condi- tions are proved to be equivalent under certain assumption. Solving of interval linear systems is used to approach other problems in the rest of the work. Computing enclosures of determinants of interval matrices is addressed. NP- hardness of both relative and absolute approximation is proved. New method based on solving square interval linear systems and Cramer's rule is designed. Various classes of matrices with polynomially computable bounds on determinant are characterized. Solving of interval linear systems is also used to compute the least squares linear and nonlinear interval regression. It is then applied to real...
95

Uma fundamenta??o para sinais e sistemas intervalares

Santana, Fabiana Trist?o de 02 December 2011 (has links)
Made available in DSpace on 2014-12-17T14:54:59Z (GMT). No. of bitstreams: 1 FabianaTS_TESE.pdf: 1364206 bytes, checksum: 5e147adc9ca5829c7a40ed214ab434d2 (MD5) Previous issue date: 2011-12-02 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In this work we use Interval Mathematics to establish interval counterparts for the main tools used in digital signal processing. More specifically, the approach developed here is oriented to signals, systems, sampling, quantization, coding and Fourier transforms. A detailed study for some interval arithmetics which handle with complex numbers is provided; they are: complex interval arithmetic (or rectangular), circular complex arithmetic, and interval arithmetic for polar sectors. This lead us to investigate some properties that are relevant for the development of a theory of interval digital signal processing. It is shown that the sets IR and R(C) endowed with any correct arithmetic is not an algebraic field, meaning that those sets do not behave like real and complex numbers. An alternative to the notion of interval complex width is also provided and the Kulisch- Miranker order is used in order to write complex numbers in the interval form enabling operations on endpoints. The use of interval signals and systems is possible thanks to the representation of complex values into floating point systems. That is, if a number x 2 R is not representable in a floating point system F then it is mapped to an interval [x;x], such that x is the largest number in F which is smaller than x and x is the smallest one in F which is greater than x. This interval representation is the starting point for definitions like interval signals and systems which take real or complex values. It provides the extension for notions like: causality, stability, time invariance, homogeneity, additivity and linearity to interval systems. The process of quantization is extended to its interval counterpart. Thereafter the interval versions for: quantization levels, quantization error and encoded signal are provided. It is shown that the interval levels of quantization represent complex quantization levels and the classical quantization error ranges over the interval quantization error. An estimation for the interval quantization error and an interval version for Z-transform (and hence Fourier transform) is provided. Finally, the results of an Matlab implementation is given / Neste trabalho utiliza-se a matem?tica intervalar para estabelecer os conceitos intervalares das principais ferramentas utilizadas em processamento digital de sinais. Mais especificamente, foram desenvolvidos aqui as abordagens intervalares para sinais, sistemas, amostragem, quantiza??o, codifica??o, transformada Z e transformada de Fourier. ? feito um estudo de algumas aritm?ticas que lidam com n?meros complexos sujeitos ? imprecis?es, tais como: aritm?tica complexa intervalar (ou retangular), aritm?tica complexa circular, aritm?tica setorial e aritm?tica intervalar polar. A partir da?, investiga-se algumas propriedades que ser?o relevantes para o desenvolvimento e aplica??o no processamento de sinais discretos intervalares. Mostra-se que nos conjuntos IR e R(C), seja qual for a aritm?tica correta adotada, n?o se tem um corpo, isto ?, os elementos desses conjuntos n?o se comportam como os n?meros reais ou complexos com suas aritm?ticas cl?ssicas e que isso ir? requerer uma avalia??o matem?tica dos conceitos necess?rios ? teoria de sinais e a rela??o desses com as aritm?ticas intervalares. Tamb?m tanto ? introduzido o conceito de amplitude intervalar complexa, como alternativa ? defini??o cl?ssica quanto utiliza-se a ordem de Kulisch-Miranker para n?meros complexos afim de que se escreva n?meros complexos intervalares na forma de intervalos, o que torna poss?vel as opera??es atrav?s dos extremos. Essa rela??o ? utilizada em propriedades de somas de intervalos de n?meros complexos. O uso de sinais e sistemas intervalares foi motivado pela representa??o intervalar num sistema de ponto flutuante abstrato. Isto ?, se um n?mero x 2 R n?o ? represent?vel em um sistema de ponto flutuante F, ele ? mapeado para um intervalo [x;x], tal que x ? o maior dos n?meros menores que x represent?vel em F e x ? o menor dos n?meros maiores que x represent?vel em F. A representa??o intervalar ? importante em processamento digital de sinais, pois a imprecis?o em dados ocorre tanto no momento da medi??o de determinado sinal, quanto no momento de process?-los computacionalmente. A partir da?, define-se sinais e sistemas intervalares que assumem tanto valores reais quanto complexos. Para isso, utiliza-se o estudo feito a respeito das aritm?ticas complexas intervalares e mostram-se algumas propriedades dos sistemas intervalares, tais como: causalidade, estabilidade, invari?ncia no tempo, homogeneidade, aditividade e linearidade. Al?m disso, foi definida a representa??o intervalar de fun??es complexas. Tal fun??o estende sistemas cl?ssicos a sistemas intervalares preservando as principais propriedades. Um conceito muito importante no processamento digital de sinais ? a quantiza??o, uma vez que a maioria dos sinais ? de natureza cont?nua e para process?-los ? necess?rio convert?-los em sinais discretos. Aqui, este processo ? descrito detalhadamente com o uso da matem?tica intervalar, onde se prop?em, inicialmente, uma amostragem intervalar utilizando as id?ias de representa??o no sistema de ponto flutuante. Posteriormente, s?o definidos n?veis de quantiza??o intervalares e, a partir da?, ? descrito o processo para se obter o sinal quantizado intervalar e s?o definidos o erro de quantiza??o intervalar e o sinal codificado intervalar. ? mostrado que os n?veis de quantiza??o intervalares representam os n?veis de quantiza??o cl?ssicos e o erro de quantiza??o intervalar representa o e erro de quantiza??o cl?ssico. Uma estimativa para o erro de quantiza??o intervalar ? apresentada. Utilizando a aritm?tica retangular e as defini??es e propriedades de sinais e sistemas intervalares, ? introduzida a transformada Z intervalar e s?o analisadas as condi??es de converg?ncia e as principais propriedades. Em particular, quando a vari?vel complexa z ? unit?ria, define-se a transformada de Fourier intervalar para sinais discretos no tempo, al?m de suas propriedades. Por fim, foram apresentadas as implementa??es dos resultados que foram feitas no software Matlab
96

Interval methods for global optimization

Moa, Belaid 22 August 2007 (has links)
We propose interval arithmetic and interval constraint algorithms for global optimization. Both of these compute lower and upper bounds of a function over a box, and return a lower and an upper bound for the global minimum. In interval arithmetic methods, the bounds are computed using interval arithmetic evaluations. Interval constraint methods instead use domain reduction operators and consistency algorithms. The usual interval arithmetic algorithms for global optimization suffer from at least one of the following drawbacks: - Mixing the fathoming problem, in which we ask for the global minimum only, with the localization problem, in which we ask for the set of points at which the global minimum occurs. - Not handling the inner and outer approximations for epsilon-minimizer, which is the set of points at which the objective function is within epsilon of the global minimum. - Nothing is said about the quality for their results in actual computation. The properties of the algorithms are stated only in the limit for infinite running time, infinite memory, and infinite precision of the floating-point number system. To handle these drawbacks, we propose interval arithmetic algorithms for fathoming problems and for localization problems. For these algorithms we state properties that can be verified in actual executions of the algorithms. Moreover, the algorithms proposed return the best results that can be computed with given expressions for the objective function and the conditions, and a given hardware. Interval constraint methods combine interval arithmetic and constraint processing techniques, namely consistency algorithms, to obtain tighter bounds for the objective function over a box. The basic building block of interval constraint methods is the generic propagation algorithm. This explains our efforts to improve the generic propagation algorithm as much as possible. All our algorithms, namely dual, clustered, deterministic, and selective propagation algorithms, are developed as an attempt to improve the efficiency of the generic propagation algorithm. The relational box-consistency algorithm is another key algorithm in interval constraints. This algorithm keeps squashing the left and right bounds of the intervals of the variables until no further narrowing is possible. A drawback of this way of squashing is that as we proceed further, the process of squashing becomes slow. Another drawback is that, for some cases, the actual narrowing occurs late. To address these problems, we propose the following algorithms: - Dynamic Box-Consistency algorithm: instead of pruning the left and then the right bound of each domain, we alternate the pruning between all the domains. - Adaptive Box-Consistency algorithm: the idea behind this algorithm is to get rid of the boxes as soon as possible: start with small boxes and extend them or shrink them depending on the pruning outcome. This adaptive behavior makes this algorithm very suitable for quick squashing. Since the efficiency of interval constraint optimization methods depends heavily on the sharpness of the upper bound for the global minimum, we must make some effort to find the appropriate point or box to use for computing the upper bound, and not to randomly pick one as is commonly done. So, we introduce interval constraints with exploration. These methods use non-interval methods as an exploratory step in solving a global optimization problem. The results of the exploration are then used to guide interval constraint algorithms, and thus improve their efficiency.
97

Analýza plodnosti prasnic ve vybraném chovu

KUBALOVÁ, Markéta January 2017 (has links)
The goal of the thesis was to analyze reproductive performance of sows in a selected breeding facility during a three-year period. 602 litters of the breed Czech Large White pig (CLW), 7 632 litters of the Czech Large White the Czech Landrace pig (CL) and 397 litters of the Czech Landrace Czech Large White were included in my observation. The average number of born piglets 15.43 was reached in the basic set of sows, out of which there were 14.25 live-born piglets. The highest number of all born piglets was found in CL CLW (16.25 pcs), followed by CLW (16.03 pcs) and CLW CL (15.34 pcs). The highest number of live-born piglets was found in CLW (14.51 pcs), then with a slight gap followed CL CLW (14.36 pcs) and the lowest number was found in CLW CL (14.22 pcs). The average age at first conception of sows was 235.7 days. Sows, younger than 229 days at first conception gave birth to 0.39 piglets more than sows of the age 230-250 days at first conception (13.42 or 13.03 piglets). The average gestation length was 115.7 days. More piglets were born to sows with gestation length shorter than 115 days, than to sows with gestation length 115 days and more (14.55 or 14.18). The difference of 0.37 piglets was statistically confirmed as highly relevant. The average length of weaning-to-conception interval was 5 days (4.97). More piglets (by 0.44) were born to sows that were serviced within 4 days after weaning, than to sows serviced within 5 and more days (15.03 or 14.58). The difference was confirmed as statistically highly relevant. The average length of farrowing interval was found 152.9 days. Sows were categorized into three groups based on this interval, 132145 days, 146-160 days and 161200 days. Most piglets were born to sows with farrowing interval 146160 days (14.58) and least to sows with farrowing interval 161200 days (14.51).
98

Hodnocení parametrů plodnosti prasnic ve vybraném chovu

MICHŇOVÁ, Iveta January 2017 (has links)
The aim of the thesis was to analyse the reproduction performance of sows achieved in selected breed. In the reporting period were on average born 12.6 total-born piglets, of which 11.7 live-born piglets. The highest number of live-born piglets was born of hybrid combination sows (CLWCL)CLW, 12.0?3.1; compared with sows CLWCL (11.8 ? 3.0) and CLW (11.6 ? 3.2). The most of live-born piglets were demonstrated from 3rd and 4th parity (12.6 ? 3.1 and 12.5 ? 3.1). Gilts at the age of first mating at 230 to 250 days, reached a higher number of live-born piglets (9.9 ? 2.8) compared to gilts with the age of first mating to 229 days (9.5 ? 2.5). Difference of 0.4 piglet was statistically highly significant. Sows with gestation length to 114 days had 1.3 piglets more (12.0 ? 3.1) than sows with gestation length 115 days or more (10.7 ? 3.1). Difference of 1.3 piglets was statistically highly significant. Sows weaning-to-conception interval within 4 days showed a higher number of live-born piglets (12.3 ? 3.0) than sows with 5 days or longer (11.4 ? 2.9). Difference of 0.9 piglet was statistically highly significant. Effect of farrowing interval (132145, 146160 and 161200 days) on the number of live-born piglets (12.1 ? 3.1; 12.2 ? 3.1 and 12.2 ? 3.2) was not statistically significant.
99

Determina??o dos intervalos de refer?ncia para lip?dios, lipoprote?nas e apolipoprote?nas no estado do Rio Grande do Norte

Fernandes, Luzia Leiros de Sena 30 August 2009 (has links)
Made available in DSpace on 2014-12-17T14:16:25Z (GMT). No. of bitstreams: 1 LuziaLSF_Dissert.pdf: 2090486 bytes, checksum: d33aa3d21b6e7f08dba8853438e95a45 (MD5) Previous issue date: 2009-08-30 / The lipid profile is a group of lab tests that include triglycerides, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C). However, serum non-HDL-C, Apo A-I and Apo B levels, as well as the lipids ratios (TC/HDL-C, LDL-C/HDL-C and Apo B/Apo A-I), have been described as better predictors of cardiovascular diseases. Reference intervals are tools often used to help the evaluation of the people s health state. These days, Brazilian studies still use the reference intervals of lipids and lipoproteins from other countries, ignoring differences between the populations. Therefore, this study aimed to establish reference intervals for lipids, lipoproteins and apolipoproteins in adults of Rio Grande do Norte/Brazil. Healthy individuals (96 men and 283 women) between 18 and 59years old formed the reference sample group. The samples were collected after fasting 12 to 14 hours. Information on lifestyle and dietary habits of the participants were obtained through questionnaire. The serum glucose level and renal and liver activity were evaluated by laboratory testing. The results of lipid profile were analyzed according to sex, age and mesoregion of Rio Grande do Norte, with significance level of 5% (p < 0,05). The lower and upper reference limits were identified by the 2.5 percentile and 97.5 percentile, respectively, and assurance intervals of 90% was calculated for each of these limits. Among the determinants of lipid profile analyzed, only a few significant differences were observed according to sex, but in terms of age, the groups of smaller and older ages were most likely different. When evaluated by region, the means of West region shown the most significant variations. Not many studies were useful to compare the reference intervals determined in this study. Thus, it becomes necessary to carry out similar studies in other regions of Brazil and of the world given the clinical importance of reference intervals / O perfil lip?dico ? definido pelas determina??es laboratoriais dos triglicer?deos, do colesterol total (CT) e das fra??es do colesterol (HDL-C e LDL-C). Por?m, as concentra??es s?ricas do n?o-HDL-C e das apolipoprote?nas A-I e B, assim como as raz?es CT/HDL-C, LDL-C/HDL-C e Apo B/Apo A-I, t?m sido descritos como melhores preditores de doen?as cardiovasculares. Os intervalos de refer?ncia s?o ferramentas frequentemente utilizadas no aux?lio da avalia??o do estado de sa?de das pessoas. Hoje, estudos nacionais ainda utilizam intervalos de refer?ncia do perfil lip?dico procedentes de outros pa?ses, desconsiderando diferen?as entre as popula??es. Assim, este trabalho objetivou estabelecer intervalos de refer?ncia para lip?dios, lipoprote?nas e apolipoprote?nas em adultos no estado do Rio Grande do Norte (RN). Ap?s uma criteriosa sele??o para compor o grupo de refer?ncia de indiv?duos sadios, foram utilizadas 379 amostras de sangue coletadas por venopun??o ap?s jejum de 12 a 14 horas, sendo 96 de homens e 283 de mulheres, ambos com idade entre 18 a 59 anos. Informa??es sobre o estilo de vida e os h?bitos alimentares dos participantes foram obtidas atrav?s de um question?rio e a avalia??o da glicemia e das fun??es renal e hep?tica foi realizada por testes laboratoriais. Os resultados do perfil lip?dico foram analisados em fun??o do sexo, da idade e da mesorregi?o do RN, sempre adotando um n?vel de signific?ncia de 5% (p < 0,05). Os limites de refer?ncia inferior e superior foram identificados atrav?s do percentil 2,5 e do percentil 97,5, respectivamente, e intervalos de confian?a de 90% foram calculados para cada um desses limites. Dentre os determinantes do perfil lip?dico estudados, poucos apresentaram diferen?a significativa quanto ao sexo mas, quanto ? idade, os grupos de menor e maior faixa et?ria foram os que mais diferiram. Quando avaliados por regi?o, os valores m?dios da mesorregi?o Oeste foram os mais diferentes significativamente. Poucos trabalhos foram ?teis para comparar os intervalos de refer?ncia determinados neste estudo. Assim, se faz necess?ria a realiza??o de estudos semelhantes a este em outras regi?es do pa?s e do mundo, visto a grande import?ncia cl?nica dos intervalos de refer?ncia
100

Agrupamento e regressão linear de dados simbólicos intervalares baseados em novas representações

SOUZA, Leandro Carlos de 28 March 2016 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-08-08T12:52:58Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) teseCinLeandro.pdf: 1316077 bytes, checksum: 61e762c7526a38a80ecab8f5c7769a47 (MD5) / Made available in DSpace on 2016-08-08T12:52:58Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) teseCinLeandro.pdf: 1316077 bytes, checksum: 61e762c7526a38a80ecab8f5c7769a47 (MD5) Previous issue date: 2016-01-18 / Um intervalo é um tipo de dado complexo usado na agregação de informações ou na representação de dados imprecisos. Este trabalho apresenta duas novas representações para intervalos com o objetivo de se construir novos métodos de agrupamento e regressão linear para este tipo de dado. O agrupamento por nuvens dinâmicas define partições nos dados e associa protótipos a cada uma destas partições. Os protótipos resumem a informação das partições e são usados na minimização de um critério que depende de uma distância, responsável por quantificar a proximidade entre instâncias e protótipos. Neste sentido, propõe-se a formulação de uma nova distância híbrida entre intervalos baseando-se em distâncias para pontos. Os pontos utilizados são obtidos dos intervalos através de um mapeamento. Também são propostas duas versões com pesos para a distância criada: uma com pesos no hibridismo e outra com pesos adaptativos. Na regressão linear, propõe-se a representação dos intervalos através da equação paramétrica da reta. Esta parametrização permite o ajuste dos pontos nas variáveis regressoras que dão as melhores estimativas para os limites da variável resposta. Antes da realização da regressão, um critério é calculado para a verificação da coerência matemática da predição, na qual o limite superior deve ser maior ou igual ao inferior. Se o critério mostra que a coerência não é garantida, propõe-se a aplicação de uma transformação sobre a variável resposta. Assim, este trabalho também propõe algumas transformações que podem ser aplicadas a dados intervalares, no contexto de regressão. Dados sintéticos e reais são utilizados para comparar os métodos provenientes das representações propostas e aqueles presentes na literatura. / An interval is a complex data type used in the information aggregation or in the representation of imprecise data. This work presents two new representations of intervals in order to construct a new cluster method and a new linear regression method for this kind of data. Dynamic clustering defines partitions into the data and it defines prototypes associated with each one of these partitions. The prototypes summarize the information about the partitions and they are used in a minimization criterion which depends on a distance, which is responsible for quantifying the proximity between instances and prototypes. In this way, it is proposed a new hybrid distance between intervals based on a family of distances between points. Points are obtained from the interval through a mapping. Also, it is proposed two versions of the hybrid distance, both with weights: one with weights in hybridism and other with adaptive weights. In linear regression, it is proposed to represent the intervals through the parametric equation of the line. This parametrization allows to find the set of points in the regression variables corresponding to the best estimates for the response variable limits. Before the regression construction, a criterion is computed to verify the mathematical consistency of prediction, where the upper limit must be greater than or equal to the lower. If the test shows that consistency is not guaranteed, then the application proposes a transformation of the response variable. Therefore, this work also proposes some transformations that can be applied to interval data in the regression context. Synthetic and real data are used to compare the proposed methods and those one proposed on literature.

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