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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.
71

Adição de celulase e período de fermentação na composição bromatológica e digestibilidade de silagens de capim mombaça / Cellulase addition and fermentation period in the bromatological composition and digestibility of plum mombaça silagens

Helrigel, Panmera Almeida 21 July 2017 (has links)
Submitted by JÚLIO HEBER SILVA (julioheber@yahoo.com.br) on 2017-10-27T18:06:41Z No. of bitstreams: 2 Dissertação - Panmera Almeida Helrigel - 2017.pdf: 1036367 bytes, checksum: f89e2ff07a0f9cf65acb53458a14fe2d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Rejected by Luciana Ferreira (lucgeral@gmail.com), reason: Observe como fica o nome do mestrado, na citação, nos que já estão na BDTD on 2017-10-30T11:01:19Z (GMT) / Submitted by JÚLIO HEBER SILVA (julioheber@yahoo.com.br) on 2017-10-30T15:47:57Z No. of bitstreams: 2 Dissertação - Panmera Almeida Helrigel - 2017.pdf: 1036367 bytes, checksum: f89e2ff07a0f9cf65acb53458a14fe2d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-10-31T09:47:42Z (GMT) No. of bitstreams: 2 Dissertação - Panmera Almeida Helrigel - 2017.pdf: 1036367 bytes, checksum: f89e2ff07a0f9cf65acb53458a14fe2d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-10-31T09:47:42Z (GMT). No. of bitstreams: 2 Dissertação - Panmera Almeida Helrigel - 2017.pdf: 1036367 bytes, checksum: f89e2ff07a0f9cf65acb53458a14fe2d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-07-21 / The present study was carried out to determine the effect of cellulase added to the silage process of the Mombaça grass, on the bromatological composition, cell wall digestibility and the minimum fermentation period to open the silo. The experimental design was completely randomized, with four replicates, in a 3 x 3 factorial scheme, three cellulase weight / weight (0, 3 and 6%) and three fermentation periods (30, 60 and 120 days), totaling 36 experimental silos. For silage, the mombaça grass was cut at an approximate height of 80 cm, at 20 cm from the ground level. The addition of the enzyme was efficient in improving the fermentative and bromatological parameters of the silages of the cultivar in question. The addition of cellulase promoted a reduction of 5.7% in the NDF contents in relation to the control, but there was also a reduction in the fiber digestibility of 6.6% in relation to the control. However, the digestibility reduction was lower in proportion to the reduction of NDF, which allowed to increase net lactation energy by 15% and NDT by 11%. The enzyme use also resulted in lower pH (4.74 vs 3.73 control and with cellulase) and higher titratable acidity (5.86 and 12.77 control and with cellulase), indicating that the cellulase allowed a fermentative process within the recommended standards. After 30 days of silage, the silages had already completed the anaerobic fermentation cycle and would be fit for consumption. After the 60 day period, the silage had a reduction of the quality parameters indicating that tropical grass silages should be used with up to 60 days of fermentation. / O presente estudo foi desenvolvido com objetivo de determinar a o efeito de celulase adicionada ao processo de ensilagem do capim Mombaça, na composição bromatológica, digestibilidade da parede celular e o período mínimo de fermentação para abertura do silo. O delineamento experimental utilizado foi inteiramente casualizado, com quatro repetições, em esquema fatorial 3 x 3, sendo três doses de celulase peso/peso (0, 3 e 6%) e três períodos de fermentação (30, 60 e 120 dias), totalizando 36 silos experimentais. Para a ensilagem, o capim mombaça foi cortado em altura aproximada de 80 cm, a 20 cm do nível do solo. A adição da enzima foi eficiente em melhorar os parâmetros fermentativos e bromatológicos das silagens do cultivar em questão. A adição de celulase promoveu redução de 5,7% nos teores de FDN, em relação ao controle, mas também houve redução na digestibilidade da fibra de 6,6% em relação ao controle. No entanto, a redução de digestibilidade foi inferior proporcionalmente à redução de FDN, o que permitiu aumentar a energia líquida de lactaçãoe em 15% e o NDT em 11%. O uso de enzima resultou também em menor pH (4,74 vs 3,73 controle e com celulase) e maior acidez titulável (5,86 e 12,77 controle e com celulase), indicando que a celulase permitiu um processo fermentativo dentro dos padrões recomendados. Após 30 dias de ensiladas, as silagens já tinham completado o ciclo de fermentação anaeróbico e estariam aptas para o consumo. Após o período de 60 dias, a silagem teve redução dos parâmetros de qualidade indicando que silagens de capins tropicais deveriam ser utilizadas com até 60 dias de fermentação.
72

Cinética da degradabilidade “in situ” da silagem do capim-mombaça com inclusão de farelo de algodão / Degradability kinetic in situ of grass mombasa silage with cottonseed meal inclusion

Merma, Gustavo Chunca 18 August 2016 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2016-09-08T12:47:37Z No. of bitstreams: 2 Dissertação - Gustavo Chunca Merma - 2016.pdf: 1384828 bytes, checksum: afbfe1a386ecbe619a04c3b198cfeb90 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-09-09T14:29:27Z (GMT) No. of bitstreams: 2 Dissertação - Gustavo Chunca Merma - 2016.pdf: 1384828 bytes, checksum: afbfe1a386ecbe619a04c3b198cfeb90 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-09-09T14:29:27Z (GMT). No. of bitstreams: 2 Dissertação - Gustavo Chunca Merma - 2016.pdf: 1384828 bytes, checksum: afbfe1a386ecbe619a04c3b198cfeb90 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-08-18 / Evaluated degradability kinetic of grass mombasa silage with inclusion levels of cottonseed meal. The treatments were constituted by four CM inclusion levels (0%, 10%, 15%, 20%). The average levels of dry matter in grass mombasa silages differed depending on cottonseed meal levels, ranging from 22.69 to 31.93. The levels of crude protein ranged from 12.51 to 22.45, and significant differences were observed at the same time promoting a reduction in the levels of insoluble fiber and neutral detergent fiber and acid detergent insoluble, thus keeping within the recommended standards, especially the 20% of CM with the highest level and lower losses by gases and effluents. The levels of hydrogenic potential (pH) ranged from 4.88 to 5.17. The nitrogen ammonia content (N-NH3), were within acceptable parameters with 1.30% to 2.59%. The average levels of soluble carbohydrates ranged from 4.60% to 8.90%, with no significant difference between the 10% and 15% levels of CM (P>0.05). The levels of lactic acid, acetic, propionic and butyric ranged from 0.2682 to 1.482; from 0.1759 to 0.3216; 0.011 to 0.0241 and from 0.0012 to 0.00162 respectively, and showed statistical difference (P>0.05) between the levels of cottonseed meal. The “in situ” dry matter degradability (DM) and crude protein (CP), neutral detergent insoluble fiber (NDIF), insoluble acid detergent fiber (IADF), were significantly influenced by the levels of inclusion of cottonseed meal (P<0.05), and highlighted the inclusion level of 20% of cottonseed meal that showed significant levels of disappearance in DM, CP, NDIF And IADF, showing that the acceptable level of cottonseed meal as addition to grass mombasa. / Avaliou-se a cinética da degradabilidade “in situ” da silagem de capim-mombaça com níveis de inclusão de farelo de algodão. Os tratamentos utilizados foram constituídos por quatro níveis de inclusão de FA (0%, 10%, 15%, 20%). Os teores médios da matéria seca nas silagens de capim-mombaça diferiram em função dos níveis do farelo de algodão, com variação de 22,69 a 31,93. Os teores da proteína bruta variaram de 12,51 a 22,45, e foram observadas diferenças significativas, ao mesmo tempo em que promoveu redução nos teores de fibras insolúveis em detergente neutro e fibras insolúveis em detergente ácido, mantendo assim dentro dos padrões recomendados, com destaque para o 20% de FA que apresentou maior nível e menores perdas por gases e efluentes. Os teores do potencial hidrogeniônico (pH) variaram de 4,88 a 5,17. Os teores de nitrogênio amoniacal (N-NH3), ficaram dentro dos parâmetros aceitáveis com 1,30% a 2,59%. Os teores médios de carboidratos solúveis variaram entre 4,60% a 8,90%, não havendo diferença significativa entre os níveis 10% e 15% de FA (P>0,05). Os teores de ácido lático, acético, propiônico e butírico variaram de 0,2682 a 1,5482; de 0,1759 a 0,3216; de 0,0114 a 0,0241 e de 0,0012 a 0,00162 respectivamente, e apresentou diferença estatística (P>0,05) entre os níveis de farelo de algodão. A degradabilidade “in situ” da matéria seca (MS) proteína bruta (PB) fibra insolúvel em detergente neutro (FDN) e fibra insolúvel em detergente ácido (FDA), foram significativamente influenciados pelos níveis de inclusão do farelo de algodão (P<0,05), tendo em destaque a inclusão do nível 20% do farelo de algodão que apresentou teores significativos de desaparecimento na MS, PB, FDN e FDA, mostrando ser o nível aceitável de farelo de algodão como adição para o capim-mombaça.
73

Momento de aplicação do nitrogênio e algumas variáveis produtivas e bromatológicas de capim-massai / Time of nitrogen application and some productive and bromatologic variables of massaigrass

Mariana Florencio Marques 09 November 2012 (has links)
O trabalho foi realizado com o objetivo de avaliar algumas variáveis estruturais e bromatológicas de Panicum maximum Jacq cv. Massai submetido a quatro doses de nitrogênio (0, 40, 80 e120 mg/dm3) e três momentos de aplicação após o corte (um, três, e sete dias), divididos em três cortes, em um esquema fatorial 4 x 3, em um delineamento inteiramente casualizado, com quatro repetições. O incremento nas taxas de aparecimento foliar (TApF), alongamento foliar (TAIF) e aparecimento de perfilhos (TApP), no número de folhas vivas (NFV), no comprimento final da folha (CFF), na densidade populacional de perfilhos (DPP), na produção de matéria seca de folha total (MSFT) e nos teores de proteína bruta (PB), foi de 79%, 115%, 42%, 23%, 48%, 65%, 770% e 35%, respectivamente para a dose de 120 mg/dm3 em relação à ausência de adubação nitrogenada. O filocrono (fil), a duração de vida da folha (DVF), a fibra em detergente neutro (FDN) e a fibra em detergente acido (FDA), apresentaram decréscimo de 58%, 47%, 6% e 9%, respectivamente, com a adição de N. A taxa de alongamento de colmo (TAlC) não respondeu a adubação nitrogenada. Apenas o CFF, a TAlC e a MSFT responderam às épocas de aplicação de N após o corte, com valores pouco expressivos. A adubação nitrogenada exerce efeito positivo sobre as variáveis estudadas, porém novos estudos devem ser conduzidos para a definição da época de adubação de N após o corte, em que o nutriente seja melhor aproveitado pelas plantas. / This work was carried out to evaluate same morphogenic, structural, bromatologic and productive variables of the Panicum maximum Jacq cv. Massai in response to four nitrogen doses (0, 40, 80 and 120 mg/dm3) and with three application times after cutting (one, three and seven days) in a 4 x 3 factorial treatment combination, in a completely randomized design, with four replications. The increase in therates of leaf appearance (LAR), leaf elongation (LER) and tillering (TR), number of live leaves (NLL), final leaf length (FLL), tiller population density (TPD), dry matter total leaf production (DMTLP) and crude protein (CP) levels was 79%, 115%, 42%, 23%, 48%, 65%, 770% and 35%, respectively for the dose of 120 mg/dm3 regarding the absence of fertilization. The phyllochron (phy) showed a decrease of 58%, the leaf life span (LLS) of 47%, the neutral detergent fiber (NDF) of 6% and acid detergent fiber (ADF) of 9%, with N addition. The stem elongation rate (SER) didnot respond to nitrogen fertilization. Only the FLL, the SER and DMTLP responded times of N application after cutting, with little significant values. Nitrogen fertilization has a positive effect on the variables studied, but news studies should be conducted to better define the time of N application after cutting, for better utilization of this nutrient by plants.
74

Haplotype Inference as a caseof Maximum Satisfiability : A strategy for identifying multi-individualinversion points in computational phasing

Bergman, Ebba January 2017 (has links)
Phasing genotypes from sequence data is an important step betweendata gathering and downstream analysis in population genetics,disease studies, and multiple other fields. This determination ofthe sequences of markers corresponding to the individualchromosomes can be done on data where the markers are in lowdensity across the chromosome, such as from single nucleotidepolymorphism (SNP) microarrays, or on data with a higher localdensity of markers like in next generation sequencing (NGS). Thesorted markers may then be used for many different analyses anddata processing such as linkage analysis, or inference of missinggenotypes in the process of imputation cnF2freq is a haplotype phasing program that uses an uncommonapproach allowing it to divide big groups of related individualsinto smaller ones. It sets an initial haplotype phase and theniteratively changes it using estimations from Hidden MarkovModels. If a marker is judged to have been placed in the wronghaplotype, a switch needs to be made so that it belongs to thecorrect phase. The objective of this project was to go fromallowing only one individual within a group to be switched in aniteration to allowing multiple switches that are dependent on eachother. The result of this project is a theoretical solution for allowingmultiple dependent switches in cnF2freq, and an implementedsolution using the max-SAT solver toulbar2.
75

Advanced methods to solve the maximum parsimony problem / Méthodes avancées pour la résolution du problème de maximum parcimonie

Vazquez ortiz, Karla Esmeralda 14 June 2016 (has links)
La reconstruction phylogénétique est considérée comme un élément central de divers domaines comme l’écologie, la biologie et la physiologie moléculaire pour lesquels les relations généalogiques entre séquences d’espèces ou de gènes, représentées sous forme d’arbres, peuvent apporter des éclairages significatifs à la compréhension de phénomènes biologiques. Le problème de Maximum de Parcimonie est une approche importante pour résoudre la reconstruction phylogénétique en se basant sur un critère d’optimalité pour lequel l’arbre comprenant le moins de mutations est préféré. Dans cette thèse nous proposons différentes méthodes pour s’attaquer à la nature combinatoire de ce problème NP-complet. Premièrement, nous présentons un algorithme de Recuit Simulé compétitif qui nous a permis de trouver des solutions de meilleure qualité pour un ensemble de problèmes. Deuxièmement, nous proposons une nouvelle technique de Path-Relinking qui semble intéressante pour comparer des arbres mais pas pour trouver des solutions de meilleure qualité. Troisièmement, nous donnons le code d’une implantation sur GPU de la fonction objectif dont l’intérêt est de réduire le temps d’exécution de la recherche pour des instances dont la longueur des séquences est importante. Finalement, nous introduisons un prédicteur capable d’estimer le score optimum pour un vaste ensemble d’instances avec une très grande précision. / Phylogenetic reconstruction is considered a central underpinning of diverse fields like ecology, molecular biology and physiology where genealogical relationships of species or gene sequences represented as trees can provide the most meaningful insights into biology. Maximum Parsimony (MP) is an important approach to solve the phylogenetic reconstruction based on an optimality criterion under which the tree that minimizes the total number of genetic transformations is preferred. In this thesis we propose different methods to cope with the combinatorial nature of this NP-complete problem. First we present a competitive Simulated Annealing algorithm which helped us find trees of better parsimony score than the ones that were known for a set of instances. Second, we propose a Path-Relinking technique that appears to be suitable for tree comparison but not for finding trees of better quality. Third, we give a GPU implementation of the objective function of the problem that can reduce the runtime for instances that have an important number of residues per taxon. Finally, we introduce a predictor that is able to estimate the best parsimony score of a huge set of instances with a high accuracy.
76

Produtividade e qualidade de 4 forrageiras em função de doses de nitrogênio / Forage productivity and quality forage as function of nitrogen fertilization

Vanalli, Luis Guilherme Galindo 04 March 2010 (has links)
Made available in DSpace on 2016-01-26T18:56:21Z (GMT). No. of bitstreams: 1 Dissertacao.pdf: 192792 bytes, checksum: 027d15a650e1c0ccad9ea4be985c1ed5 (MD5) Previous issue date: 2010-03-04 / Currently, most brazilian pastures have some degradation degree, and conservation practices are needed to improve their conditions, such as adoption of new species and fertilization, especially nitrogen. The aim of this experiment was to evaluate the quantitative and qualitative performance of four forages (Brachiaria brizantha cv. Marandú, Brachiaria decumbens, Brachiaria brizantha cv. Xaraés and Panicum maximum cv. Mombaça) after N doses application (0, 100, 200, 400 kg ha-1). The experiment was carried out at Santo Domingo Farm, located in Taciba county, in which soil type is Typic Dark. The experimental design used was a randomized block, in a 4 x 4 factorial scheme, with four replications. At early 2008 august, forages were sown manually in five rows, spaced m between rows, being conducted from 2009 September to January 2009. On 2008 October, sidedressing nitrogen fertilization was applied (60 days after emergence). The first cut was held on November 23 and the second in January 2009 (42 days after the first cut), being determined shoot dry matter yield (kg ha-1), neutral detergent fiber content and crude protein (CP). Nitrogen fertilization increases shoot dry matter yield, with emphasis on Brachiaria brizantha cv. Xaraés and Panicum maximum cv. Mombaça; Panicum maximum displays, irrespective of sidedressing nitrogen application, higher crude protein values. Brachiaria brizantha cv. Xaraés and Panicum maximum cv. Mombaça had the lowest crude fiber levels. / Atualmente, a maioria das pastagens brasileiras apresentam algum grau de degradação, sendo necessárias práticas conservacionistas para melhorar suas condições, tais como adoção de novas espécies e adubação, em especial o nitrogênio. O objetivo deste experimento foi avaliar o desempenho quantitativo e qualitativo de quatro forrageiras (Brachiaria brizantha cv. Marandú, Brachiaria decumbens, Brachiaria brizantha cv. Xaraés e Panicum maximum cv. Mombaça) após a aplicação de doses de nitrogênio (0, 100, 200, 400 kg ha-1). Assim, o experimento foi realizado na Fazenda São Domingos, localizada no município de Taciba, no qual o solo é do tipo Latossolo Vermelho Escuro. O delineamento experimental utilizado foi em blocos casualizados, em esquema fatorial 4 x 4, com quatro repetições. No início de agosto de 2008, as forrageiras foram semeadas manualmente em cinco linhas, com espaçamento de 0,30 m entrelinhas, sendo conduzidas no período entre setembro de 2008 a janeiro de 2009. No dia 15 de outubro de 2008, a adubação nitrogenada foi realizada (60 dias após a emergência). O primeiro corte foi realizado no dia 23 de novembro e o segundo no dia 4 de janeiro de 2009 (42 dias após o primeiro), sendo determinados a produtividade de matéria seca (kg ha-1), teor de fibra detergente neutro e proteína bruta (PB). A adubação nitrogenada aumenta a produtividade de matéria seca, com destaque para a Brachiaria brizantha cv. Xaraés e Panicum maximum cv. Mombaça; O Panicum maximum apresenta, independentemente da adubação nitrogenada em cobertura, maiores valores de proteína bruta. A Brachiaria brizantha cv. Xaraés e Panicum maximum cv. Mombaça apresentam os menores teores de fibra bruta.
77

Produtividade e qualidade de 4 forrageiras em função de doses de nitrogênio / Forage productivity and quality forage as function of nitrogen fertilization

Vanalli, Luis Guilherme Galindo 04 March 2010 (has links)
Made available in DSpace on 2016-07-18T17:51:06Z (GMT). No. of bitstreams: 1 Dissertacao.pdf: 192792 bytes, checksum: 027d15a650e1c0ccad9ea4be985c1ed5 (MD5) Previous issue date: 2010-03-04 / Currently, most brazilian pastures have some degradation degree, and conservation practices are needed to improve their conditions, such as adoption of new species and fertilization, especially nitrogen. The aim of this experiment was to evaluate the quantitative and qualitative performance of four forages (Brachiaria brizantha cv. Marandú, Brachiaria decumbens, Brachiaria brizantha cv. Xaraés and Panicum maximum cv. Mombaça) after N doses application (0, 100, 200, 400 kg ha-1). The experiment was carried out at Santo Domingo Farm, located in Taciba county, in which soil type is Typic Dark. The experimental design used was a randomized block, in a 4 x 4 factorial scheme, with four replications. At early 2008 august, forages were sown manually in five rows, spaced m between rows, being conducted from 2009 September to January 2009. On 2008 October, sidedressing nitrogen fertilization was applied (60 days after emergence). The first cut was held on November 23 and the second in January 2009 (42 days after the first cut), being determined shoot dry matter yield (kg ha-1), neutral detergent fiber content and crude protein (CP). Nitrogen fertilization increases shoot dry matter yield, with emphasis on Brachiaria brizantha cv. Xaraés and Panicum maximum cv. Mombaça; Panicum maximum displays, irrespective of sidedressing nitrogen application, higher crude protein values. Brachiaria brizantha cv. Xaraés and Panicum maximum cv. Mombaça had the lowest crude fiber levels. / Atualmente, a maioria das pastagens brasileiras apresentam algum grau de degradação, sendo necessárias práticas conservacionistas para melhorar suas condições, tais como adoção de novas espécies e adubação, em especial o nitrogênio. O objetivo deste experimento foi avaliar o desempenho quantitativo e qualitativo de quatro forrageiras (Brachiaria brizantha cv. Marandú, Brachiaria decumbens, Brachiaria brizantha cv. Xaraés e Panicum maximum cv. Mombaça) após a aplicação de doses de nitrogênio (0, 100, 200, 400 kg ha-1). Assim, o experimento foi realizado na Fazenda São Domingos, localizada no município de Taciba, no qual o solo é do tipo Latossolo Vermelho Escuro. O delineamento experimental utilizado foi em blocos casualizados, em esquema fatorial 4 x 4, com quatro repetições. No início de agosto de 2008, as forrageiras foram semeadas manualmente em cinco linhas, com espaçamento de 0,30 m entrelinhas, sendo conduzidas no período entre setembro de 2008 a janeiro de 2009. No dia 15 de outubro de 2008, a adubação nitrogenada foi realizada (60 dias após a emergência). O primeiro corte foi realizado no dia 23 de novembro e o segundo no dia 4 de janeiro de 2009 (42 dias após o primeiro), sendo determinados a produtividade de matéria seca (kg ha-1), teor de fibra detergente neutro e proteína bruta (PB). A adubação nitrogenada aumenta a produtividade de matéria seca, com destaque para a Brachiaria brizantha cv. Xaraés e Panicum maximum cv. Mombaça; O Panicum maximum apresenta, independentemente da adubação nitrogenada em cobertura, maiores valores de proteína bruta. A Brachiaria brizantha cv. Xaraés e Panicum maximum cv. Mombaça apresentam os menores teores de fibra bruta.
78

Cut Problems on Graphs

Nover, Alexander 18 July 2022 (has links)
Cut problems on graphs are a well-known and intensively studied class of optimization problems. In this thesis, we study the maximum cut problem, the maximum bond problem, and the minimum multicut problem through their associated polyhedra, i.e., the cut polytope, the bond polytope, and the multicut dominant, respectively. Continuing the research on the maximum cut problem and the cut polytope, we present a linear description for cut polytopes of K_{3,3}-minor-free graphs as well as an algorithm solving the maximum cut problem on these graphs in the same running time as planar maximum cut. Moreover, we give a complete characterization of simple and simplicial cut polytopes. Considering the maximum cut problem from an algorithmic point of view, we propose an FPT-algorithm for the maximum cut problem parameterized by the crossing number. We start the structural study of the bond polytope by investigating its basic properties and the effect of graph operations on the bond polytope and its facet-defining inequalities. After presenting a linear-time reduction of the maximum bond problem to the maximum bond problem on 3-connected graphs, we discuss valid and facet defining inequalities arising from edges and cycles. These inequalities yield a complete linear description for bond polytopes of 3-connected planar (K_5-e)-minor-free graphs. This polytopal result is mirrored algorithmically by proposing a linear-time algorithm for the maximum bond problem on (K_5-e)-minor-free graphs. Finally, we start the structural study of the multicut dominant. We investigate basic properties, which gives rise to lifting and projection results for the multicut dominant. Then, we study the effect of graph operations on the multicut dominant and its facet-defining inequalities. Moreover, we present facet-defining inequalities supported on stars, trees, and cycles as well as separation algorithms for the former two classes of inequalities.
79

Les justes bornes de la richesse : fondements normatifs et mise en oeuvre d'une richesse maximale / Just limits of wealth : normative foundations and implementation of the idea of maximal wealth

Jobin, Christian 02 February 2018 (has links)
Dans cette thèse, je tente d’établir les fondements normatifs d’une richesse maximale qui comprend deux mesures complémentaires : un revenu maximal qui peut être mis en œuvre au moyen d’un impôt sur le revenu et un capital maximal, au moyen d’un impôt sur les successions, dont le taux marginal est de 100 % dans les deux cas. Je soutiens en effet qu’une telle mesure est juste, puisqu’elle respecte les principes développés au sein de trois théories principales : le libertarisme, le suffisantisme et le prioritarisme. Puis, je soutiens aussi qu’une telle mesure est efficace d’un point de vue économique, puisqu’elle permet de mieux diffuser les incitations financières, ce qui peut avoir des effets positifs sur la production et la répartition de la richesse. D’abord, je soutiens qu’une richesse maximale respecte le principe fondamental défendu par les libertariens, c’est-à-dire la propriété de soi. Pour ce faire, je m’appuie surtout sur deux arguments : le proviso et la théorie des marchés où le gagnant rafle la mise. D’abord, je montre que si l’on associe les ressources naturelles au capital, l’application d’un proviso au principe d’acquisition interdit l’appropriation illimitée des ressources naturelles, ce qui permet de justifier un capital maximal. Ensuite, je montre que si l’on associe les fruits du travail au revenu, les marchés où le gagnant rafle la mise permettent à certains individus de recevoir des revenus qui sont supérieurs aux fruits de leur travail, ce qui viole par excès le principe de la propriété de soi et permet de justifier un revenu maximal. Ensuite, je soutiens qu’une richesse maximale respecte les principes développés au sein de deux théories faisant partie de la tradition égalitariste : le suffisantisme et le prioritarisme. Pour ce faire, je montre que ces deux théories ne sont acceptables que si elles intègrent une autre théorie que l’on appelle le limitarianisme. Selon cette théorie, toute richesse supérieure à celle dont un individu a besoin pour s’épanouir pleinement dans la vie peut être qualifiée d’immorale. Par conséquent, une telle théorie permet de justifier une richesse maximale, puisqu’elle ajoute un seuil de richesse au seuil de pauvreté que défendent déjà les suffisantistes et les prioritaristes.Enfin, je réponds à l’une des principales objections qui peuvent être soulevées contre une richesse maximale et qui porte sur l’efficacité économique du plafonnement des incitations financières. Je montre en effet qu’une richesse maximale, contrairement à ce que l’on pourrait croire, pourrait avoir des effets positifs sur la production et la distribution de la richesse. Pour ce faire, je m’appuie surtout sur trois arguments. D’abord, les incitations ont une importance surestimée en sciences économiques. Ensuite, il existe plusieurs formes d’incitations qui ne se réduisent nullement aux seules incitations financières. Enfin, il est préférable de diffuser largement les incitations financières plutôt que de les concentrer exagérément auprès d’une minorité d’individus. / In this thesis, I try to establish the normative foundations for a maximum limit on wealth that includes two complementary measures: a maximum on income that can be implemented by means of an income tax, and a maximum on capital, which can be attained through a tax on inheritance; the marginal rate being 100% in both cases. Indeed, I argue that such a measure is fair, since it respects the principles developed in three main theories : libertarianism, sufficientarianism, and prioritarianism. Next, I argue that such a measure is economically efficient, since it allows to better spread financial incentives, which can have positive effects on the production and distribution of wealth. First, I maintain that a maximum limit on wealth respects the fundamental principle defended by libertarians, that is, self-ownership. To do this, I rely mainly on two arguments: the proviso and the theory of winner-takes-all markets. First, I show that if we associate natural resources with capital, the application of a proviso to the principle of acquisition prohibits the unlimited appropriation of natural resources, which justifies a maximum on capital. Then, I show that if the fruits of labor are associated with income, winner-takes-all markets allow certain individuals to receive incomes that are superior to the fruits of their labor, which violates the principle of self-ownership, and thus justifies a maximum on income. Secondly, I maintain that a maximum wealth respects the principles developed within two theories within the egalitarian tradition: those of sufficientarianism and prioritarianism. To do this, I show that these two theories are acceptable only if they integrate another theory named limitarianism. According to this theory, any wealth superior to that which an individual needs to live a flourishing life can be qualified as immoral. Consequently, such a theory makes it possible to justify a maximum wealth, since it adds a wealth threshold to the poverty threshold already defended by sufficientarians, and prioritarians. Finally, I respond to one of the main objections that can be raised against maximum wealth and which deals with the economic efficiency of the capping of financial incentives. In fact, I show that maximum wealth, contrary to what one might believe, could have positive effects on the production and distribution of wealth. To do this, I rely mainly on three arguments. First, incentives are overestimated in economics. Second, there are several forms of incentives that are not limited to financial incentives alone. Finally, it is preferable to disseminate financial incentives widely rather than to exaggeratedly concentrate them on a minority of individuals.
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Peak Sidelobe Level Distribution Computation for Ad Hoc Arrays using Extreme Value Theory

Krishnamurthy, Siddhartha 25 February 2014 (has links)
Extreme Value Theory (EVT) is used to analyze the peak sidelobe level distribution for array element positions with arbitrary probability distributions. Computations are discussed in the context of linear antenna arrays using electromagnetic energy. The results also apply to planar arrays of random elements that can be transformed into linear arrays. / Engineering and Applied Sciences

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