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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.
191

Užití počítačů ve výuce na střední škole / Use computers by teaching at the middle school

BASAŘOVÁ, Martina January 2009 (has links)
This work was made like a complex of solved examples from the textbook RNDr. Pomykalová Eva: Matematika pro gymnázia {--} Stereometrie. This complex will serve students and teachers of mathematics at the middle school as an aid by teaching stereometry {--} cut the solid with a plane. Examples are solved with the software of dynamic geometry Cabri II Plus. The solids in the elemental form were created in the same software like a macro construction. I obtained these solids from my teacher on the practise. These macro constructions were created by students of mathematics in their diploma theses at the Department of Mathematic of the Pedagogical faculty in České Budějovice. All figures in the work are also enclosed on the CD ROM. In the program Cabri we can study mutual situations of figures in a space and work with them. All cuts are available too. After their opening in Cabri the teacher can view all the construction of a cut step by step with help of the respective button in menu of the program.
192

Subleading corrections to hadronic cross-sections at high energies

Cockburn, James David January 2017 (has links)
The Large Hadron Collider (LHC) has provided, and will continue to provide, data for collisions at the highest energies ever seen in a particle accelerator. A strong knowledge of the properties of amplitudes for Quantum Chromodynamics in the High Energy Limit is therefore important to interpret this data. We study this limit in the context of the High Energy Jets (HEJ) formalism. This formalism resums terms in the perturbative expansion of the cross-section that behave like αn/s log (s/-t)ⁿ¯¹, which are enhanced in this limit. Understanding this region is particularly important in certain key analyses at the LHC: for example, Higgs-boson- plus-dijet analyses where cuts are applied to pick out events with a large mjj and in many searches for new physics. In this thesis, we discuss two directions in which HEJ's accuracy has been improved. Firstly, we look at adding descriptions of partonic subprocesses which are formally sub-leading in the jet cross-section but Leading Logarithmic (LL) in the particular subprocess itself. This required the derivation of new effective vertices that describe the emission of a quark/anti-quark pair in a way that is consistent with the resummation procedure. The inclusion of such processes reduces HEJ's dependence on fixed-order calculations and marks an important step towards full Next-to-Leading Logarithmic (NLL) accuracy in the inclusive dijet cross-section. The second extension was to improve our description of events involving the emission of a Higgs boson along with jets. Specifically, we derive new effective vertices which keep the full dependence on the quark mass that appears in the loops that naturally arise in such amplitudes. The formalism is also simple enough to allow for any number of extra nal state jets in the process. Therefore, HEJ is unique in its ability to provide predictions for high-multiplicity Higgs-plus-jets processes with full nite quark mass e ects. Such a calculation is far beyond the reach of any xed order approach.
193

Tale of two loops : simplifying all-plus Yang-Mills amplitudes

Mogull, David Gustav January 2017 (has links)
Pure Yang-Mills amplitudes with all external gluons carrying positive helicity, known as all-plus amplitudes, have an especially simple structure. The tree amplitudes vanish and, up to at least two loops, the loop-level amplitudes are related to those of N = 4 super-Yang-Mills (SYM) theory. This makes all-plus amplitudes a useful testing ground for new methods of simplifing more general classes of amplitudes. In this thesis we consider three new approaches, focusing on the structure before integration. We begin with the planar (leading-colour) sector. A D-dimensional local-integrand presentation, based on four-dimensional local integrands developed for N = 4 SYM, is developed. This allows us to compute the planar six-gluon, two-loop all-plus amplitude. Its soft structure is understood before integration, and we also perform checks on collinear limits. We then proceed to consider subleading-colour structures. A multi-peripheral colour decomposition is used to find colour factors based on underlying tree-level amplitudes via generalised unitarity cuts. This allows us to find the integrand of the full-colour, two-loop, five-gluon all-plus amplitude. Tree-level BCJ relations, satisfied by amplitudes appearing in the cuts, allow us to deduce all the necessary non-planar information for the full-colour amplitude from known planar data. Finally, we consider representations satisfying colour-kinematics duality. We discuss obstacles to finding such numerators in the context of the same five-gluon amplitude at two loops. The obstacles are overcome by adding loop momentum to our numerators to accommodate tension between the values of certain cuts and the symmetries of certain diagrams. Control over the size of our ansatz is maintained by identifying a highly constraining, but desirable, symmetry property of our master numerator.
194

Short-Term Reduction of Peak Loads in Commercial Buildings in a Hot and Dry Climate

January 2012 (has links)
abstract: A major problem faced by electric utilities is the need to meet electric loads during certain times of peak demand. One of the widely adopted and promising programs is demand response (DR) where building owners are encouraged, by way of financial incentives, to reduce their electric loads during a few hours of the day when the electric utility is likely to encounter peak loads. In this thesis, we investigate the effect of various DR measures and their resulting indoor occupant comfort implications, on two prototype commercial buildings in the hot and dry climate of Phoenix, AZ. The focus of this study is commercial buildings during peak hours and peak days. Two types of office buildings are modeled using a detailed building energy simulation program (EnergyPlus V6.0.0): medium size office building (53,600 sq. ft.) and large size office building (498,600 sq. ft.). The two prototype buildings selected are those advocated by the Department of Energy and adopted by ASHRAE in the framework of ongoing work on ASHRAE standard 90.1 which reflect 80% of the commercial buildings in the US. After due diligence, the peak time window is selected to be 12:00-18:00 PM (6 hour window). The days when utility companies require demand reduction mostly fall during hot summer days. Therefore, two days, the summer high-peak (15th July) and the mid-peak (29th June) days are selected to perform our investigations. The impact of building thermal mass as well as several other measures such as reducing lighting levels, increasing thermostat set points, adjusting supply air temperature, resetting chilled water temperature are studied using the EnergyPlus building energy simulation program. Subsequently the simulation results are summarized in tabular form so as to provide practical guidance and recommendations of which DR measures are appropriate for different levels of DR reductions and the associated percentage values of people dissatisfied (PPD). This type of tabular recommendations is of direct usefulness to the building owners and operators contemplating DR response. The methodology can be extended to other building types and climates as needed. / Dissertation/Thesis / M.S. Architecture 2012
195

Presença plus : modelo de identificação de presença social em ambientes virtuais de ensino e aprendizagem

Bastos, Helvia Pereira Pinto January 2012 (has links)
Este trabalho de tese apresenta o Modelo Presença Plus (PPlus) para identificação de pistas textuais denotadoras de presença social em interações discursivas feitas por alunos em fóruns e chats educacionais. O grau de presença social (PS) é um indicativo de como os sujeitos interagem entre si e com o ambiente de aprendizagem; sendo considerado, na literatura, significativo para o desenvolvimento de relacionamentos e fortalecimento de sentimento de pertencimento no grupo. O trabalho se baseia na vertente Pragmática da Linguística, campo que enfatiza a importância de se considerar o contexto de produção dos eventos comunicativos e a dinâmica dialógica entre os interlocutores. Considerando que o mapeamento das interações dos discentes para detectar e avaliar seu grau de presença pode se constituir uma tarefa complexa e morosa para tutores de cursos a distância, desenvolveu-se um software para realizar o processamento automático das mensagens eletrônicas visando torná-lo uma funcionalidade a ser adicionada a ambientes virtuais de ensino e aprendizagem (AVEAs). Apesar de alguns impasses referentes, particularmente, aos aspectos sintáticos dos textos, os resultados obtidos no processamento, por lexicometria, das postagens foram satisfatoriamente semelhantes aos levantados na análise manual. O modelo PPlus e a escala de graus de PS foram também testados em um segundo ambiente disponibilizado na plataforma Moodle, tendo apresentado resultados equivalentes. A sondagem com professores e tutores de cursos a distância forneceu dados que corroboram a proposta de uma ferramenta a ser inserida em AVEAs de modo a facilitar o acompanhamento de estados afetivos, grau de envolvimento e interação entre os participantes no e com o ambiente. / This thesis presents Presence Plus (PPLus), a model for identifying indicators of social presence in text-based interactions made by students in educational forums and chats. The degree of social presence (SP) can be an indicator of how individuals interact among themselves and with the learning environment, and is considered by the literature to be relevant for the development of relationships and the strengthening of the sense of belonging in the group. This study is based on Pragmatics, an area of Linguistics that emphasizes the importance of the context in communicative events and the dialogic dynamics among speakers. Considering that mapping students’ interactions, as well as detecting and evaluating their degree of SP, may be a complex and time-consuming task in distance learning tutoring, a software was developed to do the automatic processing of posts, aiming at making it a possible functionality in virtual learning environments (VLEs). Despite the few conflicting results, mostly related to textual syntactic relations, data from processing tests using lexicometrics were satisfactorily similar to those obtained by manual analysis. The PPlus model and the SP scale were also tested in a different course in the Moodle platform. Results from this experiment presented equally positive data. Feedback from the questionnaire answered by teachers and tutors working in distance learning courses support the proposal of a tool that may facilitate their assessment of affective states, involvement and text-based interaction dents within the environment.
196

Análise comparativa da resposta do tecido ósseo de ratos frente ao implante de um novo cimento que contém silicato tricálcico

Quintana, Ramiro Martins January 2016 (has links)
Introdução: Materiais com modificações na formulação original do MTA, incluindo o NeoMTA Plus, têm sido desenvolvidos buscando melhorar suas propriedades físicoquímicas. O objetivo do presente estudo foi analisar a resposta do tecido ósseo de ratos Wistar frente ao implante de NeoMTA Plus em comparação com o MTA Angelus. Metodologia: 24 ratos foram anestesiados e uma broca de baixa rotação foi empregada para confeccionar três cavidades cirúrgicas no fêmur direito. As cavidades cirúrgicas foram preenchidas aleatoriamente com os materiais teste NeoMTA Plus e MTA Angelus ou deixada vazia (controle negativo). Após 7, 30 e 90 dias as características do reparo ósseo foram classificadas em escores com o auxilio de microscópio óptico. As comparações entre os grupos foram realizadas pelo teste de Friedman e as comparações entre os três períodos experimentais em cada grupo foram realizadas pelo teste de Kruskal-wallis, seguido pelo teste de Dunn. O nível de significância foi estabelecido em P<.05. Resultados: Não foram observadas diferenças estatísticas entre os materiais e o grupo controle nos 3 tempos experimentais. Em todos os grupos houve diferença estatisticamente significante entre os tempos de 7 e 30 dias e nenhuma diferença foi observada entre os tempos de 30 e 90 dias. Além disso, o reparo em 90 dias foi significativamente melhor do que em 7 dias nos grupos NeoMTA Plus e controle. Conclusões: O NeoMTA Plus demonstrou comportamento biológico satisfatório em contato direto com o tecido ósseo de ratos Wistar, apresentando resultados semelhantes aos grupos MTA Angelus e controle. / Introduction: Materials that alter the original formulation of MTA have been developed to improve physical-chemical properties, including NeoMTA Plus (NMTAP). The aim of the present study was to analyze bone tissue reactions to NMTAP compared to MTA Angelus (MTA-A). Methods: 24 animals were anesthetized and a slow-rotation bur was used to create three surgical cavities in their right femur. Surgical cavities were randomly designated to NMTAP, MTA-A and negative control (empty cavity) groups. After 7, 30, and 90 days histological analysis of the characteristics of bone repair were classified in scores. Friedman’s test performed intergroup comparisons and Kruskal-Wallis test, followed by the Dunn’s post hoc test, compared the three experimental periods in each group. The significance level was set at P<.05. Results: No differences were found between the materials and control group in each experimental period. In all groups, the bone tissue repair improved from 7 to 30 days and there was no difference from 30 to 90 days. Moreover, the repair at 90 days was significantly better than at 7 in NMTAP and control groups. Conclusions: NeoMTA Plus showed satisfactory biological behavior when in direct contact with rat bone tissue, presenting repair characteristics similar to those produced by MTA Angelus and by the control group.
197

Citlivost tetry jeskynní (Astyanax mexicanus) k magnetickému poli / Sensitivity to magnetic field in Mexican Cavefish

JANDA, Patrik January 2018 (has links)
This thesis deals with the detection of magnetic field perception of cavefishes the Mexican tetra (Astyanax mexicanus). The experiments were carried out in a plus-shaped maze where the direction preference in the individual arms of this maze was studied both in the natural Earth´s magnetic field and in the modified one by using magnets and turning the north-south axis by 90°. The reactions of the specimen on placing a strong magnet close behind the end of the western and later also the eastern arm of the plus-shaped maze were also monitored. It was conclusively found that the Mexican tetra prefer north-south axis. However, after turning the magnetic field by 90° there was no preference of the specimen for the new north-south axis as we expected. Although some of the tests performed here show the perceptiveness of magnetic field of the Mexican tetra and their preference for the noth-south axis, other tests disprove the formulated hypothesis. That is why other new hypotheses about the perceptiveness of the magnetic field should be created so that they could not be disproved in either case. This thesis has served as a stepping stone for further research in the field of magnetoreception of cavefishes.
198

Calcul d'itinéraire multicritère en transport multimodal / Multicriteria trip planning in multimodal transportation networks

Iglesias, Alexandre 12 October 2017 (has links)
Les travaux effectués dans cette thèse industrielle concernent l'amélioration du calculateur d'itinéraire de Cityway, société spécialisée dans les technologies de l’information appliquées à la mobilité.Nous avons d'abord établi un état de l'art exhaustif, accompagné d'une mise en perspective de l'existant Cityway avec celui-ci. Cela nous a permis d'aider l'entreprise à prendre du recul sur son produit et de justifier les axes de recherche choisis pour nos travaux.Nous nous sommes ensuite intéressés à l'aspect multicritère du problème. En effet, le calculateur, basé sur l'algorithme de Dijkstra, permet de trouver des trajets minimisant une somme pondérée de critères. Nous avons développé un algorithme multilabel permettant de conserver et étendre plusieurs labels au même nœud. Malgré une légère augmentation des temps de calculs, des résultats satisfaisants ont été obtenus dans une application bicritère de ce nouvel algorithme.Nous avons également travaillé sur la génération et la sélection de trajets alternatifs. La génération s'appuie sur les algorithmes monolabel ou multilabel. La sélection s'appuie quant à elle sur la définition d'une distance entre les solutions et des méthodes de regroupement.Enfin, nous nous sommes intéressés à l'optimisation du calcul du critère lexicographique de durée minimale dans le cas bicritère. Pour qu'un trajet soit intéressant, il faut qu'il soit optimal sur les critères usuels, mais aussi qu'il dure le moins longtemps possible. L'utilisation de certaines propriétés sur ce critère permet de réduire des temps de calcul initialement trop longs. / The work carried out in this industrial PhD aims at improving the route planner of Cityway, a company specialized in information technologies applied to mobility. We first established an exhaustive state of the art, and compared it to the existing Cityway product. This allowed us to help the company take a step back from its urgent needs, and justify the research guidelines chosen for our work.We then looked at the multi-criteria aspect of the problem. Indeed, the trip planner, based on the Dijkstra algorithm, makes it possible to find paths minimizing a weighted sum of criteria. We have developed a multilabel algorithm to maintain and extend multiple labels at the same node. Despite a slight increase in computation time, satisfactory results were obtained in a bicriteria application of this new algorithm.We also worked on the generation and selection of alternative routes. The generation algorithm relies on the existing monolabel or newly developed multilabel algorithms. The selection algorithm is based on the definition of a distance between trips and adaptations of existing clustering algorithms to this specific case.Finally, we were interested in what we called the lexicographic criterion. For a trip to be interesting, it must be optimal on the usual criterion of earliest arrival, and, for trips arriving at the same time, on the latest departure criterion. The use of certain properties on this criterion makes it possible to reduce computation times on the bicriteria case.
199

Art and Effective Altruism: Case Studies in Sustainable Practice

January 2017 (has links)
abstract: Effective Altruism (EA), a moral philosophy concerned with accomplishing the greatest possible good in one’s lifetime, sees little utilitarian and/or humanitarian value in the arts. EA suggests that amidst so much global strife, the time, energy, and finances expended to create fleeting art would be put to better, more practical use in the fight against poverty. However, EA has yet to sufficiently account for sustainable art practice — an art form deeply rooted in utilitarianism and humanitarianism — and the possibility of its accompanying aesthetics as a constituent of utilitarian/humanitarian theories. The first chapter of this thesis illustrates an intersection of EA, sustainability, and aesthetics, detailing ways in which sustainable art and EA philosophy overlap, as well as problematizing EA’s dismissal of contemporary art practice. This chapter also points to sustainable art as one possible alternative art route for practicing artists with EA interests. Chapters two and three present case studies of Danish art collective SUPERFLEX and an American non-profit called the Land Art Generator Initiative (LAGI) and how their sustainable goals fit the utilitarian and humanitarian scope through which EA functions. / Dissertation/Thesis / Masters Thesis Art History 2017
200

Modulação dos receptores 5-HT1A e 5-HT2C DO complexo amigdalóide sobre os efeitos da fluoxetina na antinocicepção induzida pelo confinamento de camundongos aos braços do labirinto em cruz elevado

Tavares, Ligia Renata Rodrigues 23 March 2016 (has links)
Submitted by Daniele Amaral (daniee_ni@hotmail.com) on 2016-10-18T17:34:40Z No. of bitstreams: 1 DissLRRT.pdf: 1317373 bytes, checksum: 51206e583775263173013e3c30ea57eb (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-21T14:03:14Z (GMT) No. of bitstreams: 1 DissLRRT.pdf: 1317373 bytes, checksum: 51206e583775263173013e3c30ea57eb (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-21T14:03:21Z (GMT) No. of bitstreams: 1 DissLRRT.pdf: 1317373 bytes, checksum: 51206e583775263173013e3c30ea57eb (MD5) / Made available in DSpace on 2016-10-21T14:03:27Z (GMT). No. of bitstreams: 1 DissLRRT.pdf: 1317373 bytes, checksum: 51206e583775263173013e3c30ea57eb (MD5) Previous issue date: 2016-03-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Previous studies have implicated the 5HT1A and 5HT2C serotonin receptors subtypes located within the amygdala in the modulation of defensive behaviors in rodents exposed to the elevated plus-maze (EPM). Further studies have shown that exposure to a threatening stimulus can result in pain inhibition. This study evaluated the effects of intra-amygdala injections of 5HT1A and 5HT2C receptor agonists on open arms antinociception (OAA) in the EPM, and possible alterations of this response with concomitant fluoxetine treatment. Male Swiss mice received 0.1 μl intra-amygdala injections of either 5.6 or 10 nmol of 8-OHDPAT, a 5-HT1A receptor agonist, and an i.p. injection of 0.6% acetic acid, a nociceptive stimulus. After confirming the start of writhing, half of the animals in each group were confined to the OA and half to the EA of the EPM, to record the number of writhes during a five-minute period (Experiment 1) A similar experimental protocol was repeated in the experiments described below. Subsequently, the animals received combined injections of fluoxetine (2.5mg/kg) and 10 nmol of 8-OHDPAT (Experiment 2). In Experiment 3, the animals received injections of either 0.21 or 0.63 nmol of MK-212, a 5-HT2C receptor agonist, and combined injections of fluoxetine (2.5mg/kg) and 0.63 nmol of MK-212 (Experiment 4). Our results showed that intra-amygdala infusions of 8-OH-DPAT enhanced nociception in both arms. Combined administration of fluoxetine and 8-OH-DPAT did not alter the observed effects. Injection of MK-212 increased the OAA, while combined administration of fluoxetine and MK-212 reversed the increase in OAA observed with MK-212 injection. These findings suggest that OAA is mediated by 5-HT2C and 5-HT1A receptors located in the amygdala. Fluoxetine interacted with 5-HT2C receptors, blocking the increase of OAA induced by activation of this serotonin receptor subtype. / Estudos têm demonstrado que os subtipos de receptores serotonérgicos 5HT1A e 5HT2C localizados na amígdala estão envolvidos na modulação de comportamentos defensivos avaliados em camundongos expostos ao labirinto em cruz elevado (LCE). Além disso, evidências demonstram que a exposição a situações ameaçadoras podem resultar em inibição da dor. Este estudo avaliou os efeitos da fluoxetina sobre a modulação da nocicepção pelos receptores 5-HT1A e 5-HT2C da amígdala em camundongos confinados nos braços abertos (BA) e fechados (BF) do LCE. Camundongos machos da linhagem suíço-albino receberam 0,1ul de injeções intra-amígdala de 8-OH-DPAT (agonista do receptor 5HT1A) nas doses de 5,6 ou 10 nmol e em seguida, uma injeção de ácido acético (estímulo nociceptivo), 0,6% (0,1ml/10g por peso corpóreo, i.p.). Após a confirmação do início das contorções, os camundongos foram confinados no BA ou BF do LCE durante 5 minutos para o registro do número de contorções abdominais (Experimento 1). Este protocolo sucedeu-se para os demais experimentos. Subsequentemente, os animais receberam injeções combinadas de fluoxetina (2,5 mg/kg, s.c.) e 10 nmol de 8-OH-DPAT intra-amígdala (Experimento 2). No experimento 3, os animais receberam injeções intra-amígdala de 0,21 ou 0,63mol de MK-212 (agonista do receptor 5-HT2C) e injeções combinadas de fluoxetina (2,5 mg/kg, s.c.) e 0,63nmol de MK-212 intra-amígdala (Experimento 4). Os nossos resultados mostraram que as injeções intraamígdalade 8-OH-DPAT acentuaram a nocicepção nos animais confinados em ambos os braços do LCE. A administração combinada de fluoxetina, e 8-OH-DPAT intra-amígdala não alterou os efeitos observados deste agonista do receptor 5HT1A. A microinjeção de MK-212 aumentou a antinocicepção induzida pelo BA, enquanto a administração combinada de fluoxetina e MK-212 intra-amígdala reverteu o aumento da antinocicepção induzida pelo BA observado com a microinjeção de MK-212 intra-amígdala. Estes resultados mostram que a antinocicepção induzida pelo BA do LCE pode ser mediada tanto pelos receptores 5-HT1A como por receptores 5-HT2C localizados na amígdala de camundongos. Entretanto, o bloqueio do aumento da antinocicepção induzida por situações aversivas promovido pela fluoxetina ocorreu apenas na interação com os receptores 5-HT2C.

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