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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.
111

Algorithmic Approaches to Pattern Mining from Structured Data / 構造データからのパターン発見におけるアルゴリズム論的アプローチ

Otaki, Keisuke 23 March 2016 (has links)
The contents of Chapter 6 are based on work published in IPSJ Transactions on Mathematical Modeling and Its Applications, vol.9(1), pp.32-42, 2016. / 京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第19846号 / 情博第597号 / 新制||情||104(附属図書館) / 32882 / 京都大学大学院情報学研究科知能情報学専攻 / (主査)教授 山本 章博, 教授 鹿島 久嗣, 教授 阿久津 達也 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM
112

On the existence and enumeration of sets of two or three mutually orthogonal Latin squares with application to sports tournament scheduling

Kidd, Martin Philip 03 1900 (has links)
Thesis (PdD)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: A Latin square of order n is an n×n array containing an arrangement of n distinct symbols with the property that every row and every column of the array contains each symbol exactly once. It is well known that Latin squares may be used for the purpose of constructing designs which require a balanced arrangement of a set of elements subject to a number of strict constraints. An important application of Latin squares arises in the scheduling of various types of balanced sports tournaments, the simplest example of which is a so-called round-robin tournament — a tournament in which each team opposes each other team exactly once. Among the various applications of Latin squares to sports tournament scheduling, the problem of scheduling special types of mixed doubles tennis and table tennis tournaments using special sets of three mutually orthogonal Latin squares is of particular interest in this dissertation. A so-called mixed doubles table tennis (MDTT) tournament comprises two teams, both consisting of men and women, competing in a mixed doubles round-robin fashion, and it is known that any set of three mutually orthogonal Latin squares may be used to obtain a schedule for such a tournament. A more interesting sports tournament design, however, and one that has been sought by sports clubs in at least two reported cases, is known as a spouse-avoiding mixed doubles round-robin (SAMDRR) tournament, and it is known that such a tournament may be scheduled using a self-orthogonal Latin square with a symmetric orthogonal mate (SOLSSOM). These applications have given rise to a number of important unsolved problems in the theory of Latin squares, the most celebrated of which is the question of whether or not a set of three mutually orthogonal Latin squares of order 10 exists. Another open question is whether or not SOLSSOMs of orders 10 and 14 exist. A further problem in the theory of Latin squares that has received considerable attention in the literature is the problem of counting the number of (essentially) different ways in which a set of elements may be arranged to form a Latin square, i.e. the problem of enumerating Latin squares and equivalence classes of Latin squares of a given order. This problem quickly becomes extremely difficult as the order of the Latin square grows, and considerable computational power is often required for this purpose. In the literature on Latin squares only a small number of equivalence classes of self-orthogonal Latin squares (SOLS) have been enumerated, namely the number of distinct SOLS, the number of idempotent SOLS and the number of isomorphism classes generated by idempotent SOLS of orders 4 n 9. Furthermore, only a small number of equivalence classes of ordered sets of k mutually orthogonal Latin squares (k-MOLS) of order n have been enumerated in the literature, namely main classes of 2-MOLS of order n for 3 n 8 and isotopy classes of 8-MOLS of order 9. No enumeration work on SOLSSOMs appears in the literature. In this dissertation a methodology is presented for enumerating equivalence classes of Latin squares using a recursive, backtracking tree-search approach which attempts to eliminate redundancy in the search by only considering structures which have the potential to be completed to well-defined class representatives. This approach ensures that the enumeration algorithm only generates one Latin square from each of the classes to be enumerated, thus also generating a repository of class representatives of these classes. These class representatives may be used in conjunction with various well-known enumeration results from the theory of groups and group actions in order to determine the number of Latin squares in each class as well as the numbers of various kinds of subclasses of each class. This methodology is applied in order to enumerate various equivalence classes of SOLS and SOLSSOMs of orders up to and including order 10 and various equivalence classes of k-MOLS of orders up to and including order 8. The known numbers of distinct SOLS, idempotent SOLS and isomorphism classes generated by idempotent SOLS are verified for orders 4 n 9, and in addition the number of isomorphism classes, transpose-isomorphism classes and RC-paratopism classes of SOLS of these orders are enumerated. The search is further extended to determine the numbers of these classes for SOLS of order 10 via a large parallelisation of the backtracking treesearch algorithm on a number of processors. The RC-paratopism class representatives of SOLS thus generated are then utilised for the purpose of enumerating SOLSSOMs, while existing repositories of symmetric Latin squares are also used for this purpose as a means of validating the enumeration results. In this way distinct SOLSSOMs, standard SOLSSOMs, transposeisomorphism classes of SOLSSOMs and RC-paratopism classes of SOLSSOMs are enumerated, and a repository of RC-paratopism class representatives of SOLSSOMs is also produced. The known number of main classes of 2-MOLS of orders 3 n 8 are verified in this dissertation, and in addition the number of main classes of k-MOLS of orders 3 n 8 are also determined for 3 k n−1. Other equivalence classes of k-MOLS of order n that are enumerated include distinct k-MOLS and reduced k-MOLS of orders 3 n 8 for 2 k n − 1. Finally, a filtering method is employed to verify whether any SOLS of order 10 satisfies two basic necessary conditions for admitting a common orthogonal mate with its transpose, and it is found via a computer search that only four of the 121 642 class representatives of RC-paratopism classes of SOLS satisfy these conditions. It is further verified that none of these four SOLS admits a common orthogonal mate with its transpose. By this method the spectrum of resolved orders in terms of the existence of SOLSSOMs is improved in that the non-existence of such designs of order 10 is established, thereby resolving a longstanding open existence question in the theory of Latin squares. Furthermore, this result establishes a new necessary condition for the existence of a set of three mutually orthogonal Latin squares of order 10, namely that such a set cannot contain a SOLS and its transpose / AFRIKAANSE OPSOMMING: ’n Latynse vierkant van orde n is ’n n × n skikking van n simbole met die eienskap dat elke ry en elke kolom van die skikking elke element presies een keer bevat. Dit is welbekend dat Latynse vierkante gebruik kan word in die konstruksie van ontwerpe wat vra na ’n gebalanseerde rangskikking van ’n versameling elemente onderhewig aan ’n aantal streng beperkings. ’n Belangrike toepassing van Latynse vierkante kom in die skedulering van verskeie spesiale tipes gebalanseerde sporttoernooie voor, waarvan die eenvoudigste voorbeeld ’n sogenaamde rondomtalietoernooi is — ’n toernooi waarin elke span elke ander span presies een keer teenstaan. Onder die verskeie toepassings van Latynse vierkante in sporttoernooi-skedulering, is die probleem van die skedulering van spesiale tipes gemengde dubbels tennis- en tafeltennistoernooie deur gebruikmaking van spesiale versamelings van drie paarsgewys-ortogonale Latynse vierkante in hierdie proefskrif van besondere belang. In sogenaamde gemengde dubbels tafeltennis (GDTT) toernooi ding twee spanne, elk bestaande uit mans en vrouens, op ’n gemengde-dubbels rondomtalie wyse mee, en dit is bekend dat enige versameling van drie paarsgewys-ortogonale Latynse vierkante gebruik kan word om ’n skedule vir s´o ’n toernooi op te stel. ’n Meer interessante sporttoernooi-ontwerp, en een wat al vantevore in minstens twee gerapporteerde gevalle deur sportklubs benodig is, is egter ’n gade-vermydende gemengde-dubbels rondomtalie (GVGDR) toernooi, en dit is bekend dat s´o ’n toernooi geskeduleer kan word deur gebruik te maak van ’n self-ortogonale Latynse vierkant met ’n simmetriese ortogonale maat (SOLVSOM). Hierdie toepassings het tot ’n aantal belangrike onopgeloste probleme in die teorie van Latynse vierkante gelei, waarvan die mees beroemde die vraag na die bestaan van ’n versameling van drie paarsgewys ortogonale Latynse vierkante van orde 10 is. Nog ’n onopgeloste probleem is die vraag na die bestaan van SOLVSOMs van ordes 10 en 14. ’n Verdere probleem in die teorie van Latynse vierkante wat aansienlik aandag in die literatuur geniet, is die bepaling van die getal (essensieel) verskillende maniere waarop ’n versameling elemente in ’n Latynse vierkant gerangskik kan word, m.a.w. die probleem van die enumerasie van Latynse vierkante en ekwivalensieklasse van Latynse vierkante van ’n gegewe orde. Hierdie probleem raak vinnig baie moeilik soos die orde van die Latynse vierkant groei, en aansienlike berekeningskrag word dikwels hiervoor benodig. Sover is slegs ’n klein aantal ekwivalensieklasse van self-ortogonale Latynse vierkante (SOLVe) in die literatuur getel, naamlik die getal verskillende SOLVe, die getal idempotente SOLVe en die getal isomorfismeklasse voortgebring deur idempotente SOLVe van ordes 4 n 9. Verder is slegs ’n klein aantal ekwivalensieklasse van geordende versamelings van k onderling ortogonale Latynse vierkante (k-OOLVs) in die literatuur getel, naamlik die getal hoofklasse voortgebring deur 2-OOLVs van orde n vir 3 n 8 en die getal isotoopklasse voortgebring deur 8-OOLVs van orde 9. Daar is geen enumerasieresultate oor SOLVSOMs in die literatuur beskikbaar nie. In hierdie proefskrif word ’n metodologie vir die enumerasie van ekwivalensieklasse van Latynse vierkante met behulp van ’n soekboomalgoritme met terugkering voorgestel. Hierdie algoritme poog om oorbodigheid in die soektog te minimeer deur net strukture te oorweeg wat die potensiaal het om tot goed-gedefinieerde klasleiers opgebou te word. Hierdie eienskap verseker dat die algoritme slegs een Latynse vierkant binne elk van die klasse wat getel word, genereer, en dus word ’n databasis van verteenwoordigers van hierdie klasse sodoende opgebou. Hierdie klasverteenwoordigers kan tesame met verskeie welbekende groepteoretiese telresultate gebruik word om die getal Latynse vierkante in elke klas te bepaal, asook die getal verskeie deelklasse van verskillende tipes binne elke klas. Die bogenoemde metodologie word toegepas om verskeie SOLV- en SOLVSOM-klasse van ordes kleiner of gelyk aan 10 te tel, asook om k-OOLV-klasse van ordes kleiner of gelyk aan 8 te tel. Die getal verskillende SOLVe, idempotente SOLVe en isomorfismeklasse voortgebring deur SOLVe word vir ordes 4 n 9 geverifieer, en daarbenewens word die getal isomorfismeklasse, transponent-isomorfismeklasse en RC-paratoopklasse voortgebring deur SOLVe van hierdie ordes ook bepaal. Die soektog word deur middel van ’n groot parallelisering van die soekboomalgoritme op ’n aantal rekenaars ook uitgebrei na die tel van hierdie klasse voortgebring deur SOLVe van orde 10. Die verteenwoordigers van RC-paratoopklasse voortgebring deur SOLVe wat deur middel van hierdie algoritme gegenereer word, word dan gebruik om SOLVSOMs te tel, terwyl bestaande databasisse van simmetriese Latynse vierkante as validasie van die resultate ook vir hierdie doel ingespan word. Op hierdie manier word die getal verskillende SOLVSOMs, standaardvorm SOLVSOMs, transponent-isomorfismeklasse voortgebring deur SOLVSOMs asook RC-paratoopklasse voortgebring deur SOLVSOMs bepaal, en word ’n databasis van verteenwoordigers van RC-paratoopklasse voortgebring deur SOLVSOMs ook opgebou. Die bekende getal hoofklasse voortgebring deur 2-OOLVs van ordes 3 n 8 word in hierdie proefskrif geverifieer, en so ook word die getal hoofklasse voortgebring deur k- OOLVs van ordes 3 n 8 bepaal, waar 3 k n−1. Ander ekwivalensieklasse voortgebring deur k-OOLVs van orde n wat ook getel word, sluit in verskillende k-OOLVs en gereduseerde k-OOLVs van ordes 3 n 8, waar 2 k n − 1. Laastens word daar van ’n filtreer-metode gebruik gemaak om te bepaal of enige SOLV van orde 10 twee basiese nodige voorwaardes om ’n ortogonale maat met sy transponent te deel kan bevredig, en daar word gevind dat slegs vier van die 121 642 klasverteenwoordigers van RC-paratoopklasse voortgebring deur SOLVe van orde 10 aan hierdie voorwaardes voldoen. Dit word verder vasgestel dat geeneen van hierdie vier SOLVe ortogonale maats in gemeen met hul transponente het nie. Die spektrum van afgehandelde ordes in terme van die bestaan van SOLVSOMs word dus vergroot deur aan te toon dat geen sulke ontwerpe van orde 10 bestaan nie, en sodoende word ’n jarelange oop bestaansvraag in die teorie van Latynse vierkante beantwoord. Verder bevestig hierdie metode ’n nuwe noodsaaklike bestaansvoorwaarde vir ’n versameling van drie paarsgewys-ortogonale Latynse vierkante van orde 10, naamlik dat s´o ’n versameling nie ’n SOLV en sy transponent kan bevat nie. / Harry Crossley Foundation / National Research Foundation
113

l'évaluation de requêtes avec un délai constant

Kazana, Wojciech 16 September 2013 (has links) (PDF)
Cette thèse se concentre autour du problème de l'évaluation des requêtes. Étant donné une requête q et une base de données D, l'objectif est de calculer l'ensemble q(D) des nuplets résultant de l'évaluation de q sur D. Toutefois, l'ensemble q(D) peut être plus grand que la base de données elle-même car elle peut avoir une taille de la forme n^l où n est la taille de la base de données et l est l'arité de la requête. Calculer entièrement q(D) peut donc nécessiter plus que les ressources disponibles. L'objectif principal de cette thèse est une solution particulière à ce problème: une énumération de q(D) avec un délai constant. Intuitivement, cela signifie qu'il existe un algorithme avec deux phases: une phase de pré-traitement qui fonctionne en temps linéaire dans la taille de la base de données, suivie d'une phase d'énumération produisant un à un tous les éléments de q(D) avec un délai constant (indépendant de la taille de la base de données) entre deux éléments consécutifs. En outre, quatre autres problèmes sont considérés: le model-checking (où la requête q est un booléen), le comptage (où on veut calculer la taille |q(D)|), les tests (où on s'intéresse à un test efficace pour savoir si un uplet donné appartient au résultat de la requête) et la j-ième solution (où on veut accéder directement au j-ième élément de q(D)). Les résultats présentés dans cette thèse portent sur les problèmes ci-dessus concernant: - les requêtes du premier ordre sur les classes de structures de degré borné, - les requêtes du second ordre monadique sur les classes de structures de largeur d'arborescente bornée, - les requêtes du premier ordre sur les classes de structures avec expansion bornée.
114

Perfil de excreção de Salmonella em suínos ao abate e presença de carcaças positivas no pré-resfriamento

Paim, Daniel Santos January 2016 (has links)
A presença de Salmonella no conteúdo intestinal do suíno ao abate é a principal fonte de contaminação da carcaça. O processo de abate embora capaz de controlar a contaminação de carcaças pode não ser capaz de garantir baixa frequência de carcaças positivas para Salmonella em lotes que apresentam elevado número de suínos excretores. O objetivo deste estudo exploratório foi acompanhar lotes suínos abatidos em um matadouro-frigorífico em relação à presença de excretores de Salmonella no conteúdo intestinal e à frequência de carcaças positivas para Salmonella no pré-resfriamento. O estudo foi conduzido em dez dias de abate; em cada dia, cinco suínos foram amostrados, totalizando 50 animais, destes foram coletados: sangue, conteúdo intestinal, suabes de superfície da carcaça nas etapas de pós-sangria e pré-resfriamento. O soro foi submetido ao teste ELISA-Typhimurium; Salmonella foi enumerada no conteúdo intestinal pela técnica do Numero Mais Provável (NMP); e nos suabes de carcaça foi realizada pesquisa de Salmonella e enumeração de Mesófilos aeróbios totais (MAT) e Enterobactérias. Todos os suínos foram positivos na pesquisa de IgG anti-Salmonella, em 64% destes Salmonella foi detectada no conteúdo intestinal em médias estimadas entre 2,7 e >1.400 NMP/g de conteúdo intestinal. A superfície das carcaças apresentou média de 3,28 log UFC/cm2 de MAT, quando amostradas na pós-sangria. As mesmas carcaças, na etapa de pré-resfriamento, apresentaram médias entre 1,43 e 2,48 log UFC/cm2, observando-se uma redução logarítmica média de 0,64 a 2,35 UFC/cm2 entre as etapas de coleta. A enumeração de Enterobactérias apresentou maior variação entre os dias e entre as etapas de abate. Na etapa de pós-sangria as médias variaram de 0,27 a 2,64 log UFC/cm2. Já no pré-resfriamento as médias variaram de -0,71 até 0,46 log UFC/cm2. Em relação ao isolamento de Salmonella, houve uma frequência de 16% (8/50) de carcaças positivas na etapa de pós-sangria e 8% (4/50) no pré-resfriamento. Os sorovares Typhimurium, Derby, Infantis e O:4,5 foram encontrados nas carcaças. As quatro carcaças positivas no pré-resfriamento foram originadas de suínos que apresentaram Salmonella no conteúdo intestinal; duas delas provenientes de um mesmo dia de abate, no qual todos os suínos apresentavam elevado número de Salmonella no conteúdo intestinal (130 até > 1.400 NMP/g-1). Os resultados obtidos indicam que lotes de abate com suínos apresentando alta contagem de Salmonella no conteúdo intestinal podem apresentar maior frequência de carcaças positivas no pré-resfriamento, mesmo em processos de abate de acordo com os padrões higiênico-sanitários. / The presence of Salmonella in the intestinal contents of slaughter pigs is considered the main source for carcass contamination. The slaughter process can control the contamination of carcasses, but may not be able to ensure a low frequency of Salmonella-positive carcasses in slaughter batches that have a high number of shedders. The objective of this exploratory study was to follow slaughter pig batches for the presence of Salmonella in intestinal content and to determine the frequency of Salmonella-positive pre-chill carcasses. The study was conducted in ten slaughter; in each day five pigs were sampled for: blood, intestinal contents; carcass surface swabs taken at the post-bleeding and pre-chill steps. The serum was subjected to the ELISA- Typhimurium test; Salmonella was enumerated in the intestinal contents by the Most Probable Number (MPN) protocol; and carcass swabs were subjected to Salmonella detection and enumeration of Total aerobic mesophilic (MAT) and Enterobacteriaceae. All pigs were positive in the anti-Salmonella IgG testing, in 64% of them Salmonella was detected in the intestinal contents. The estimated Salmonella mean ranged from 2.7 to > 1,400 MPN/g-1 of intestinal content. In the carcass surface an averaged of 3.28 log CFU/cm2 of MAT was found at the post-bleeding step. The same carcasses presented averages between 1.43 and 2.48 log CFU/cm2 in the pre-cooling stage, corresponding to a mean log reduction from 0.64 to 2.35 log CFU/cm2 between steps. Enumeration of Enterobacteriaceae showed a greater variation between days and slaughtering stages. In the post-bleeding step averages ranged from 0.27 to 2.64 log CFU/cm2. In the pre-cooling the average ranged from -0.71 to 0.46 log CFU/cm2. Regarding the isolation of Salmonella, the frequency was 16% (8/50) of positive carcasses at the post-bleeding step and 8% (4/50) at the pre-chilling. The serovar Typhimurium, Derby, Infantis and O:4,5 were found in the carcasses. The four positive carcasses in the pre-cooling step originated from pigs that had Salmonella in intestinal contents, two of them were slaughter on a same day, in which all pigs had a high number of Salmonella in intestinal contents (130 to > 1,400 MPN/g-1). The results indicate that slaughter pig batches presenting high counts of Salmonella in intestinal contents may have higher frequency of positive carcasses in the pre-chilling, even in slaughtering processes complying to hygienic-sanitary standards.
115

Reliability Based Water Distribution Network Design

Akkas, Izzet Saygin 01 November 2006 (has links) (PDF)
The need of water and the limited sources, force the researchers to find the most economical and feasible solution in the design of a water distribution network. In this study, reliability and optimization of a water distribution network are taken into account together in the design stage of the network. The relationship between reliability of a water distribution network and its cost is examined during the design of a water distribution network. A methodology for deciding the reliability level of the selected design is proposed by examining the reliability-cost relationship. The design alternatives for the case study area are obtained by the aid of a commercially available software WADISO employing partial enumeration optimization technique. The reliability value for each of the design alternative is calculated according to Misirdali (2003)&rsquo / s adaptation based on the methodology proposed by Bao and Mays (1990) by the aid of a hydraulic network solver program HapMam prepared by Nohut&ccedil / u (2002). For purposes of illustration, the skeletonized form of Ankara Water Distribution Network subpressure zone (N8-1) is taken as the case study area. The methodology in this study, covering the relation between the reliability and the cost of a water distribution network and the proposed reliability level can be used in the design of new systems.
116

Aufzählen von DNA-Codes / Enumeration of DNA codes

Bärmann, Daniel January 2006 (has links)
In dieser Arbeit wird ein Modell zum Aufzählen von DNA-Codes entwickelt. Indem eine Ordnung auf der Menge aller DNA-Codewörter eingeführt und auf die Menge aller Codes erweitert wird, erlaubt das Modell das Auffinden von DNA-Codes mit bestimmten Eigenschaften, wie Überlappungsfreiheit, Konformität, Kommafreiheit, Stickyfreiheit, Überhangfreiheit, Teilwortkonformität und anderer bezüglich einer gegebenen Involution auf der Menge der Codewörter. Ein auf Grundlage des geschaffenen Modells entstandenes Werkzeug erlaubt das Suchen von Codes mit beliebigen Kombinationen von Codeeigenschaften. Ein weiterer wesentlicher Bestandteil dieser Arbeit ist die Untersuchung der Optimalität von DNA-Codes bezüglich ihrer Informationsrate sowie das Finden solider DNA-Codes. / In this work a model for enumerating DNA codes is developed. By applying an order on the set of DNA codewords and extending this order on the set of codes, this model assists in the discovery of DNA codes with properties like non-overlappingness, compliance, comma-freeness, sticky-freeness, overhang-freeness, subword-compliance, solidness and others with respect to a given involution on the set of codewords. This tool can be used to find codes with arbitrary combinations of code properties with respect to the standard Watson-Crick-DNA involution. The work also investigates DNA codes with respect to the optimizing of the information rate, as well as finding solid DNA codes.
117

Water Distribution Network Design By Partial Enumeration

Keles, Gultekin 01 December 2005 (has links) (PDF)
Water distribution networks are being designed by traditional methods based on rules-of-thumb and personal experience of the designer. However, since there is no unique solution to any network design, namely there are various combinations of pipes, pumps, tanks all of which satisfy the same pressure and velocity restrictions, it is most probable that the design performed by traditional techniques is not the optimum one. This study deals how an optimization technique can be a useful tool for a designer during the design to find a solution. The method used within the study is the partial enumeration technique developed by Gessler. The technique is applied by a commercially available software, i.e. WADISO SA. The study is focused on discrepancies between a network designed by traditional techniques and the same network designed by partial enumeration method. Attention is given to steps of enumeration, which are basically grouping of pipes, candidate pipe size and price function assignments, to demonstrate that the designers can control all the phases of optimization process. In this respect, special attention is given to price functions to show the effect of them on the result. The study also revealed that the cost of fitting materials cannot be included in the price function although it may have significant effect in a system composed of closely located junctions. The results obtained from this study are useful to show that although optimization methods do not provide a definite solution / partial enumeration method can assist designers to select the optimum system combination.
118

Perfil de excreção de Salmonella em suínos ao abate e presença de carcaças positivas no pré-resfriamento

Paim, Daniel Santos January 2016 (has links)
A presença de Salmonella no conteúdo intestinal do suíno ao abate é a principal fonte de contaminação da carcaça. O processo de abate embora capaz de controlar a contaminação de carcaças pode não ser capaz de garantir baixa frequência de carcaças positivas para Salmonella em lotes que apresentam elevado número de suínos excretores. O objetivo deste estudo exploratório foi acompanhar lotes suínos abatidos em um matadouro-frigorífico em relação à presença de excretores de Salmonella no conteúdo intestinal e à frequência de carcaças positivas para Salmonella no pré-resfriamento. O estudo foi conduzido em dez dias de abate; em cada dia, cinco suínos foram amostrados, totalizando 50 animais, destes foram coletados: sangue, conteúdo intestinal, suabes de superfície da carcaça nas etapas de pós-sangria e pré-resfriamento. O soro foi submetido ao teste ELISA-Typhimurium; Salmonella foi enumerada no conteúdo intestinal pela técnica do Numero Mais Provável (NMP); e nos suabes de carcaça foi realizada pesquisa de Salmonella e enumeração de Mesófilos aeróbios totais (MAT) e Enterobactérias. Todos os suínos foram positivos na pesquisa de IgG anti-Salmonella, em 64% destes Salmonella foi detectada no conteúdo intestinal em médias estimadas entre 2,7 e >1.400 NMP/g de conteúdo intestinal. A superfície das carcaças apresentou média de 3,28 log UFC/cm2 de MAT, quando amostradas na pós-sangria. As mesmas carcaças, na etapa de pré-resfriamento, apresentaram médias entre 1,43 e 2,48 log UFC/cm2, observando-se uma redução logarítmica média de 0,64 a 2,35 UFC/cm2 entre as etapas de coleta. A enumeração de Enterobactérias apresentou maior variação entre os dias e entre as etapas de abate. Na etapa de pós-sangria as médias variaram de 0,27 a 2,64 log UFC/cm2. Já no pré-resfriamento as médias variaram de -0,71 até 0,46 log UFC/cm2. Em relação ao isolamento de Salmonella, houve uma frequência de 16% (8/50) de carcaças positivas na etapa de pós-sangria e 8% (4/50) no pré-resfriamento. Os sorovares Typhimurium, Derby, Infantis e O:4,5 foram encontrados nas carcaças. As quatro carcaças positivas no pré-resfriamento foram originadas de suínos que apresentaram Salmonella no conteúdo intestinal; duas delas provenientes de um mesmo dia de abate, no qual todos os suínos apresentavam elevado número de Salmonella no conteúdo intestinal (130 até > 1.400 NMP/g-1). Os resultados obtidos indicam que lotes de abate com suínos apresentando alta contagem de Salmonella no conteúdo intestinal podem apresentar maior frequência de carcaças positivas no pré-resfriamento, mesmo em processos de abate de acordo com os padrões higiênico-sanitários. / The presence of Salmonella in the intestinal contents of slaughter pigs is considered the main source for carcass contamination. The slaughter process can control the contamination of carcasses, but may not be able to ensure a low frequency of Salmonella-positive carcasses in slaughter batches that have a high number of shedders. The objective of this exploratory study was to follow slaughter pig batches for the presence of Salmonella in intestinal content and to determine the frequency of Salmonella-positive pre-chill carcasses. The study was conducted in ten slaughter; in each day five pigs were sampled for: blood, intestinal contents; carcass surface swabs taken at the post-bleeding and pre-chill steps. The serum was subjected to the ELISA- Typhimurium test; Salmonella was enumerated in the intestinal contents by the Most Probable Number (MPN) protocol; and carcass swabs were subjected to Salmonella detection and enumeration of Total aerobic mesophilic (MAT) and Enterobacteriaceae. All pigs were positive in the anti-Salmonella IgG testing, in 64% of them Salmonella was detected in the intestinal contents. The estimated Salmonella mean ranged from 2.7 to > 1,400 MPN/g-1 of intestinal content. In the carcass surface an averaged of 3.28 log CFU/cm2 of MAT was found at the post-bleeding step. The same carcasses presented averages between 1.43 and 2.48 log CFU/cm2 in the pre-cooling stage, corresponding to a mean log reduction from 0.64 to 2.35 log CFU/cm2 between steps. Enumeration of Enterobacteriaceae showed a greater variation between days and slaughtering stages. In the post-bleeding step averages ranged from 0.27 to 2.64 log CFU/cm2. In the pre-cooling the average ranged from -0.71 to 0.46 log CFU/cm2. Regarding the isolation of Salmonella, the frequency was 16% (8/50) of positive carcasses at the post-bleeding step and 8% (4/50) at the pre-chilling. The serovar Typhimurium, Derby, Infantis and O:4,5 were found in the carcasses. The four positive carcasses in the pre-cooling step originated from pigs that had Salmonella in intestinal contents, two of them were slaughter on a same day, in which all pigs had a high number of Salmonella in intestinal contents (130 to > 1,400 MPN/g-1). The results indicate that slaughter pig batches presenting high counts of Salmonella in intestinal contents may have higher frequency of positive carcasses in the pre-chilling, even in slaughtering processes complying to hygienic-sanitary standards.
119

Perfil de excreção de Salmonella em suínos ao abate e presença de carcaças positivas no pré-resfriamento

Paim, Daniel Santos January 2016 (has links)
A presença de Salmonella no conteúdo intestinal do suíno ao abate é a principal fonte de contaminação da carcaça. O processo de abate embora capaz de controlar a contaminação de carcaças pode não ser capaz de garantir baixa frequência de carcaças positivas para Salmonella em lotes que apresentam elevado número de suínos excretores. O objetivo deste estudo exploratório foi acompanhar lotes suínos abatidos em um matadouro-frigorífico em relação à presença de excretores de Salmonella no conteúdo intestinal e à frequência de carcaças positivas para Salmonella no pré-resfriamento. O estudo foi conduzido em dez dias de abate; em cada dia, cinco suínos foram amostrados, totalizando 50 animais, destes foram coletados: sangue, conteúdo intestinal, suabes de superfície da carcaça nas etapas de pós-sangria e pré-resfriamento. O soro foi submetido ao teste ELISA-Typhimurium; Salmonella foi enumerada no conteúdo intestinal pela técnica do Numero Mais Provável (NMP); e nos suabes de carcaça foi realizada pesquisa de Salmonella e enumeração de Mesófilos aeróbios totais (MAT) e Enterobactérias. Todos os suínos foram positivos na pesquisa de IgG anti-Salmonella, em 64% destes Salmonella foi detectada no conteúdo intestinal em médias estimadas entre 2,7 e >1.400 NMP/g de conteúdo intestinal. A superfície das carcaças apresentou média de 3,28 log UFC/cm2 de MAT, quando amostradas na pós-sangria. As mesmas carcaças, na etapa de pré-resfriamento, apresentaram médias entre 1,43 e 2,48 log UFC/cm2, observando-se uma redução logarítmica média de 0,64 a 2,35 UFC/cm2 entre as etapas de coleta. A enumeração de Enterobactérias apresentou maior variação entre os dias e entre as etapas de abate. Na etapa de pós-sangria as médias variaram de 0,27 a 2,64 log UFC/cm2. Já no pré-resfriamento as médias variaram de -0,71 até 0,46 log UFC/cm2. Em relação ao isolamento de Salmonella, houve uma frequência de 16% (8/50) de carcaças positivas na etapa de pós-sangria e 8% (4/50) no pré-resfriamento. Os sorovares Typhimurium, Derby, Infantis e O:4,5 foram encontrados nas carcaças. As quatro carcaças positivas no pré-resfriamento foram originadas de suínos que apresentaram Salmonella no conteúdo intestinal; duas delas provenientes de um mesmo dia de abate, no qual todos os suínos apresentavam elevado número de Salmonella no conteúdo intestinal (130 até > 1.400 NMP/g-1). Os resultados obtidos indicam que lotes de abate com suínos apresentando alta contagem de Salmonella no conteúdo intestinal podem apresentar maior frequência de carcaças positivas no pré-resfriamento, mesmo em processos de abate de acordo com os padrões higiênico-sanitários. / The presence of Salmonella in the intestinal contents of slaughter pigs is considered the main source for carcass contamination. The slaughter process can control the contamination of carcasses, but may not be able to ensure a low frequency of Salmonella-positive carcasses in slaughter batches that have a high number of shedders. The objective of this exploratory study was to follow slaughter pig batches for the presence of Salmonella in intestinal content and to determine the frequency of Salmonella-positive pre-chill carcasses. The study was conducted in ten slaughter; in each day five pigs were sampled for: blood, intestinal contents; carcass surface swabs taken at the post-bleeding and pre-chill steps. The serum was subjected to the ELISA- Typhimurium test; Salmonella was enumerated in the intestinal contents by the Most Probable Number (MPN) protocol; and carcass swabs were subjected to Salmonella detection and enumeration of Total aerobic mesophilic (MAT) and Enterobacteriaceae. All pigs were positive in the anti-Salmonella IgG testing, in 64% of them Salmonella was detected in the intestinal contents. The estimated Salmonella mean ranged from 2.7 to > 1,400 MPN/g-1 of intestinal content. In the carcass surface an averaged of 3.28 log CFU/cm2 of MAT was found at the post-bleeding step. The same carcasses presented averages between 1.43 and 2.48 log CFU/cm2 in the pre-cooling stage, corresponding to a mean log reduction from 0.64 to 2.35 log CFU/cm2 between steps. Enumeration of Enterobacteriaceae showed a greater variation between days and slaughtering stages. In the post-bleeding step averages ranged from 0.27 to 2.64 log CFU/cm2. In the pre-cooling the average ranged from -0.71 to 0.46 log CFU/cm2. Regarding the isolation of Salmonella, the frequency was 16% (8/50) of positive carcasses at the post-bleeding step and 8% (4/50) at the pre-chilling. The serovar Typhimurium, Derby, Infantis and O:4,5 were found in the carcasses. The four positive carcasses in the pre-cooling step originated from pigs that had Salmonella in intestinal contents, two of them were slaughter on a same day, in which all pigs had a high number of Salmonella in intestinal contents (130 to > 1,400 MPN/g-1). The results indicate that slaughter pig batches presenting high counts of Salmonella in intestinal contents may have higher frequency of positive carcasses in the pre-chilling, even in slaughtering processes complying to hygienic-sanitary standards.
120

Tópicos em combinatória / Topics in combinatorics

Domingues, Deborah Pereira 16 August 2018 (has links)
Orientador: José Plínio de Oliveira Santos / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matemática, Estatística e Computação Científica / Made available in DSpace on 2018-08-16T18:39:44Z (GMT). No. of bitstreams: 1 Domingues_DeborahPereira_M.pdf: 925996 bytes, checksum: 6a430acfaa4475e03a36ee7e09bbf42a (MD5) Previous issue date: 2010 / Resumo: Neste trabalho estudamos dois importantes tópicos em combinatória. O primeiro deles é o Teorema Enumerativo de Pólya. No capítulo 2 é dada uma demonstração deste teorema usando o Teorema de Burnside. Também neste capítulo, encontram-se algumas de suas diversas aplicações. O segundo tópico trata de Teoria de Partições. Esta dissertação aborda alguns objetos de estudo desta área. O primeiro objeto é o método de Partition Analisys, usado para achar funções geradoras de vários tipos de interessantes funções de partição. Ainda relacionado a funções geradoras, o capítulo 3 aborda um pouco sobre q-séries. O segundo objeto é o método gráfico, que utiliza a representação gráfica de Ferrers para uma partição. Ainda neste capítulo, são usados os conceitos de quadrado de Durfee e símbolo de Frobenius para provar algumas identidades. / Abstract: This paper presents two important topics in combinatorics. The first one is the Pólya Enumeration Theorem. In chapter 2 is given a demonstration of this theorem by Burnside's Theorem. Also in this chapter are some of their various applications. The second topic deals with the Theory of Partition. This dissertation addresses some aspects of the study on this area. The first is Partition Analysis, this method is used to find the generating functions of various kinds of interesting partition functions. In the third chapter we deal with q-series which is also related to generating functions. The second is the graphical method, which uses a Ferrers's graphical representation of a partition. In addition, we use the concepts of Durfee square and Frobenius's symbol to prove some identities. / Mestrado / Mestre em Matemática

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