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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.
141

Miglotosios logikos grandžių ir struktūrų modelių sudarymas / The Formation of Fuzzy Logic Links and Structural Models

Strelčiūnienė, Rima 10 September 2004 (has links)
The topic of the work for Master’s degree is: “The formation of fuzzy logic links and structural models”. The purpose of this work is to design a calculator, which would make arithmetic operations with the elements of fuzzy logic. This programme would allow to make such operations with fussy logic elements: addition (+), substraction (–), multiplication (×), division ( : ). Five main parts are presented in the work: analytical one, designed one, the documentation of the consumer, the evaluation of fuzzy logic calculator, the conclusions. In the first part the analysis of fussy arithmetic operation is made, the operations which can be applied in designing are given. In the second part the requirements of the consumer are analyzed and functional requirements are given. The specification of the system is made. The schedule of the project performance is set. The measures of project hazard and prevention are set. The testing, which has been made is described. The plan of system developing is presented. In the third part the documentation of consumer is written. In the fourth part a thorough analysis of calculator working is made, its advantages and disadvantages, fields of application are singled out. The fifth part is the conclusions. Fussy logic makes it possible to achieve much better management characteristics than by traditional methods. One may use the designed calculator by teaching the course of “Calculating methods with indefinite sets” and will help students to master... [to full text]
142

Širdies susitraukimų dažnio ir žingsnių parametrų sąsajos atliekant Conconi testą / The links of heart rate and step parameters in the Conconi test

Šliževičiūtė, Nora 20 June 2012 (has links)
Tyrimo hipotezė: atliekant laiptiškai sunkėjantį krūvį, pasiekus LKS, turėtų atsirasti pokyčiai žingsnio parametruose. Tyrimo tikslas: nustatyti širdies susitraukimų dažnio ir žingsnių parametrų sąsajas atliekant Conconi testą. Siekiant šio tikslo buvo užsibrėžti šie uždaviniai: 1. Nustatyti ir įvertinti ŠSD pokyčius Conconi testo metu ir nustatyti La kaupimosi slenksčius. 2. Nustatyti ir įvertinti žingsnio parametrų (žingsnio dažnio, žingsnio ilgio, atramos trukmės ir polėkio trukmės) pokyčius Conconi testo metu. 3. Nustatyti sąsajas tarp ŠSD ir žingsnio parametrų Conconi testo metu. Tiriamąją imtį sudarė 8 vyrai – ištvermės atstovai bėgikai, kurie atliko Conconi testą. Tiriant buvo naudojamas ActiGraph ActiTrain prietaisas, kuriuo registravome ŠSD ir žingsnių dažnį. Kinematiniams parametrams išmatuoti naudojome dvi, 100 Hz dažnio sinchronines kameras, kuriomis fiksavome žingsnio parametrus. Šiuos parametrus, specializuotą judesių analizės programą SIMI MOTION 2D, apskaičiavome atramos, polėkio ir žingsnio trukmes (s), žingsnio ilgį (m), žingsnio dažnį (k/s) ir bėgimo greitį (m/s). La slenksčio nustatymui naudojome Orgin 6.0 programą. Rodiklių sąsajos kaitai vertinti pasinaudojome Kauno mokslininkų (Vainoras ir kt. 2008) sukurta matricinės analizės metodika. Tyrimo rezultatai parodė, kad nuosekliai didėjant bėgimo greičiui ir pasiekus 14.57±1.47 km/h bėgimo greitį, pradeda kauptis laktatas, tuo pat metu ŠSD būna 171.91±7.66 t/min. Maksimalus ŠSD - 195.14±6.32 t/min... [toliau žr. visą tekstą] / The hypothesis of the work: there should be an appearance of changes in step parameters when reaching VMS while performing activities with gradual increase of workload. The aim of the work is to determine the links of heart rate and step parameters in the Conconi test. To achieve this aim we have been established the following objectives: 1. Identify and evaluate changes in heart rate and the La accumulation thresholds during the Conconi test. 2. Identify and evaluate the parameters of step (step frequency, stride length, head length and flight time) changes during the Conconi test. 3. Identify the relationship between heart rate and steps parameters. The sample consisted of 8 men - representatives of endurance runners who have completed the Conconi test. During the test was used an ActiGraph ActiTrain device, which registered the heart rate and steps rates. To measure the kinematic parameters, we used two synchronous cameras of 100 Hz, which recorded the steps parameters. These parameters with an specialized motion analysis program SIMI MOTION 2D we calculated the support, enthusiasm and step time (s), stride length (m), step frequency (t/s) and running speed (m/s). To determinate the La threshold we uses a 6.0 Orgin program. To evaluate the indicators of the interface changes we took advantage the analysis of a matrix methodology scientist of Kaunas (Vainoras et al. 2008). The results have shown that lactate begins to accumulate at a consistent increase in running speed... [to full text]
143

FAULT LINKS: IDENTIFYING MODULE AND FAULT TYPES AND THEIR RELATIONSHIP

Michael, Inies Raphael Chemmannoor 01 January 2004 (has links)
The presented research resulted in a generic component taxonomy, a generic code-faulttaxonomy, and an approach to tailoring the generic taxonomies into domain-specific aswell as project-specific taxonomies. Also, a means to identify fault links was developed.Fault links represent relationships between the types of code-faults and the types ofcomponents being developed or modified. For example, a fault link has been found toexist between Controller modules (that forms a backbone for any software via. itsdecision making characteristics) and Control/Logic faults (such as unreachable code).The existence of such fault links can be used to guide code reviews, walkthroughs, testingof new code development, as well as code maintenance. It can also be used to direct faultseeding. The results of these methods have been validated. Finally, we also verified theusefulness of the obtained fault links through an experiment conducted using graduatestudents. The results were encouraging.
144

Achieving near-optimal MIMO capacity in a rank-deficient LOS environment

Walkenhorst, Brett T. 29 June 2009 (has links)
In the field of wireless multiple-input multiple-output (MIMO) communications, remarkable capacity enhancements may be achieved in certain environments relative to single-antenna systems. In a non-line of sight (NLOS) environment with rich multipath, the capacity potential is typically very good, but in a line of sight (LOS) environment with a high Rician K-factor, the capacity improvement may be severely limited or almost disappear. The objective of the research described in this dissertation has been to develop a more thorough understanding of the capacity limitations of MIMO in a LOS environment and explore methods to improve that capacity. It is known that for a LOS link with a given range, an optimal antenna configuration, which usually involves large antenna spacings, can be computed to maximize the capacity. A method is here proposed for achieving near-maximum MIMO capacity in LOS environments with suboptimal array configurations. Suboptimal arrays may include small antenna spacings and/or arrays rotated off normal. The method employs single-antenna full-duplex, amplify-and-forward relays, otherwise known as "wireless repeaters." We have designated this concept repeater-assisted capacity enhancement (RACE) for MIMO. Potential applications include tower-mounted or building-top cellular backhaul and high-speed wireless bridge links (explored in Chapter 5) and ground-to-air sensor network backhaul links and base-to-mobile links in a cellular configuration (explored in Chapter 7). We have analyzed this concept in simulation for point-to-point and point-to-multipoint links and have found the following critical parameters for system design and deployment: orientation, antenna spacing, and antenna patterns of the transmit (TX)/receive (RX) MIMO arrays; and position, noise figure, TX/RX isolation, and antenna patterns associated with the repeater(s). Simulation results for an n[subscript R] xn[subscript T] MIMO link demonstrate nearly a factor of n=min{n[subscript R], n[subscript T] } improvement in capacity relative to a single-input single-output (SISO) link using n-1 optimally placed wireless repeaters supporting the link. Other portions of analysis presented include the development of a determinant-based metric for capacity (D) and an exploration of upper and lower bounds of capacity as a function of D. The position of repeaters is analyzed theoretically and a metric introduced based on D intended to quickly and intuitively determine optimal positions for repeaters assisting a given MIMO link based on TX/RX node steering vectors.
145

A geometric investigation of reach

Korein, James Urey. January 1900 (has links)
Thesis (Ph. D.)--University of Pennsylvania, 1984. / Includes bibliographical references (p. [196]-206) and index.
146

A geometric investigation of reach

Korein, James Urey. January 1900 (has links)
Thesis (Ph. D.)--University of Pennsylvania, 1984. / Includes bibliographical references (p. [196]-206) and index.
147

Interação universidade-empresa: o caso da Universidade Federal de Santa Maria / University-industry links: Universidade Federal de Santa Maria case

Lopes, João Alfredo Carvalho 28 February 2013 (has links)
The university-industry interaction increasingly becomes a major mechanism to change knowledge into innovation. This study evaluate whether this interaction contributes to development of companies and research groups in Federal University of Santa Maria context. Was considered the academic and business perspective. The academic side was carried out among research groups that maintains interaction with productive sector among their activities. On the business side were investigated companies that maintain collaboration with the university. The study used a qualitative and exploratory approach. We interviewed directors of four companies and four directors of leading research groups, representing three companies and three research groups. The evaluation of interactions used four dimensions: profile, process, structural factors and outcomes. These dimensions were used for both academic and business side. The results showed that the main contribution of business side was related to innovation in products and processes. Regarding competitiveness, the cooperation influence was less observable and indirect. Regarding sustainability, academic contribution was virtually nonexistent. From university side, interaction showed benefits in all parts of fundamental academic mission - teaching, research and extension - plus benefits in infrastructure. However, from the standpoint of innovation only one of research groups showed technological results. In general it was found that interaction of university researchers with productive sector contributes to development of university and business. / A interação entre o setor acadêmico e empresarial torna-se cada vez mais um dos principais mecanismos para transformar conhecimento em inovação. Este estudo buscou avaliar o processo de interação universidade-empresa na Universidade Federal de Santa Maria e sua contribuição para o desenvolvimento das empresas e grupos de pesquisa envolvidos. Buscouse avaliar esta contribuição por meio da perspectiva acadêmica e empresarial. Na perspectiva acadêmica, o estudo foi realizado junto a grupos de pesquisa que mantêm interação com o setor produtivo entre as suas atividades. No âmbito empresarial, foram investigadas empresas que mantêm colaboração com a universidade. O procedimento metodológico utilizado compreendeu uma pesquisa qualitativa, de caráter exploratório. Foram entrevistados quatro diretores de empresas e quatro líderes de grupos de pesquisa, representando três empresas e três grupos de pesquisa. A avaliação das interações utilizou quatro dimensões: perfil, processo, fatores estruturais e resultados. Estas dimensões foram utilizadas tanto no âmbito acadêmico quanto no empresarial. Os resultados evidenciaram que a principal contribuição na perspectiva empresarial foi a inovação em produtos e processos. Em relação à competitividade, a cooperação teve influência menos perceptível e indireta. Com relação à sustentabilidade, a contribuição acadêmica foi praticamente inexistente. Na perspectiva da universidade, a interação mostrou benefícios em todas as partes do tripé acadêmico fundamental - ensino, pesquisa e extensão - além de benefícios em infraestrutura. Porém, do ponto de vista da inovação, apenas um dos grupos de pesquisa evidenciou resultados de cunho tecnológico. De forma geral, verificou-se que a interação de pesquisadores da universidade com o setor produtivo contribui para o desenvolvimento da universidade e das empresas.
148

TCP sur lien asymétrique : analyse des phénomènes et étude de solutions de faible empreinte mémoire ou de bout-en-bout / Asymmetric link and TCP : analysis and end-to-end or low footprint solutions

Braud, Tristan 11 July 2016 (has links)
L'utilisation de TCP sur des liens asymétriques entraîne fréquemment des débits plus faibles qu'attendus au point de nuire sensiblement à la qualité de service ressentie par l'utilisateur. Ces baisses de performances peuvent prendre diverses formes parmi lesquelles une forte latence en début de connexion, une sous utilisation de la capacité du lien ou encore des latences excessivement hautes pour l'ensemble de la connexion. Afin de contrer ces effets, plusieurs approches sont possibles, que ce soit de bout-en-bout par des modifications de la pile TCP/IP ou en cœur de réseau avec divers mécanismes d'ordonnancement. L'objectif de cette thèse est d'explorer comment un résultat similaire à celui obtenu par des méthodes d'ordonnancement au goulot d'étranglement peut être obtenu en travaillant de bout-en-bout, c'est à dire là où les ressources de calcul et de mémoire sont les plus abondantes. Ce questionnement est accompagné par une analyse en profondeur des phénomènes causant une dégradation des performances, ainsi que l'évaluation des solutions existantes. Finalement, des solutions nouvelles, en cœur de réseau ainsi que de bout en bout, ont été apportées et testées sur banc d'essai. / Using TCP on asymmetric links may lead to unexpected and significant performance drops, severely degrading user experience. Those performance drops can come in various forms, among which a huge latency at the beginning of a connection, under-utilization of link capacities, or even excessive delays for the whole connection.In order to prevent those effects to happen, various approaches exist, either end-to-end through changes in the TCP/IP stack, or in the network core with a collection of scheduling algorithms.The first goal of this thesis is to explore if and how an end-to-end policy (i.e where CPU and memory resources are the most abundant) can achieve similar results as buffering policies in the core of the network. Secondly, we provide an in-depth analysis of the root cause of the performance drops, and evaluate existing algorithms. Finally, new solutions, both end-to-end and in the core of the network, are brought and tested in real life networks.
149

Encodage de données programmable et à faible surcoût, limité en disparité et en nombre de bits identiques consécutifs / Programmable Low Overhead, Run Length Limited and DC-Balanced Line Coding for High-Speed Serial Data Transmission

Saade, Julien 03 June 2015 (has links)
Grace à leur simplicité de routage, la réduction du bruit, de la consommation d'energie, d'espace de routage et d'interférences électromagnétiques en comparaison avec les liaisons parallèles, les Liaisons Série Haut Débit (High-Speed Serial Links) se trouvent aujourd'hui dans la grande majorité des systèmes sur puce (SoC) connectant les différents composants : la puce principale avec ses entrées/sorties, la puce principale avec une autre puce, la communication inter-processeurs etc…Par contre, changer des liaisons parallèles pour utiliser des liaisons séries haut débit présente plusieurs défi : les liaisons série haut débit doivent tourner à des fréquences plus élevées que celle des liaisons parallèles pour atteindre plusieurs Gigabits par seconde (Gbps) pour garder le même débit que celui des liaisons parallèles, tout en répondant à l'augmentation exponentielle de la demande de débit. L'atténuation du signal sur le cuivre augmente avec la fréquence, nécessitant de plus en plus d'égaliseurs et de techniques de filtrage, et donc augmentant la complexité du design et la consommation d'énergie.L'une des façons pour optimiser le design avec des hautes fréquences c'est d'intégrer l'horloge dans la ligne de données, car une ligne d'horloge implique plus de surface de routage et elle pourra bien devenir une source d'interférences électromagnétiques (EMI). Une autre bonne raison pour utiliser une horloge intégrée c'est que la déviation du signal d'horloge par rapport au signal de data (skew en anglais) devient difficile à contrôler sur des fréquences élevées. Des transitions doivent donc être assurées dans les données transmises, pour que le récepteur soit capable de se synchroniser et de récupérer les données correctement. En d'autres termes, le nombre de bits consécutifs, aussi appelé la Run Length (RL) en anglais doit être réduit ou borné à une certaine limite.Un autre défi ou caractéristique à réduire ou borner dans les données à transmettre est la différence entre le nombre de bits à 1 et le nombre de bits à 0 transmis. On l'appelle la disparité RD (de l'anglais Running Disparity). Les grands écarts entre le nombre de bits à 1 et les bits à 0 transférés peuvent provoquer un décalage du signal par rapport à la ligne de base. On appelle ça le Baseline Wander en anglais (BLW). Le BLW pourra augmenter le taux de bits erronés (Bit Error Rate – BER) ou exiger des techniques de filtrage et d'égalisations au récepteur pour être corrigé. Cela va donc augmenter la complexité du design et la consommation d'énergie.Pour assurer une RL et une RD bornées, les données à transmettre sont généralement encodés. A travers le temps, plusieurs méthodes d'encodages ont été présentées et utilisées dans les standards ; certaines présentent de très bonnes caractéristiques mais au cout d'un grand nombre supplémentaire de bits, en anglais appelé Overhead, affectant donc le débit. D'autres encodages ont un overhead moins important mais n'assurent pas les mêmes limites de RL et de RD, et par conséquence ils nécessitent plus de complexité analogique pour corriger les conséquences et donc augmentant ainsi la consommation d'énergie.Dans cette thèse, on propose un nouvel encodage de données qui peut borner la RD et la RL pour les bornes souhaités, et avec un très faible cout sur la bande passante (l'overhead). Ce codage permet de borner la RL et la RD aux mêmes limites que les autres codages et avec un overhead 10 fois moins important.Dans un premier temps on montre comment on peut borner la RL à la valeur souhaitée avec un codage à très faible overhead. Dans un second temps on propose un encodage très faible cout pour borner la RD à la valeur souhaitée aussi. Ensuite on montrera comment on pourra fusionner ces deux encodages en un seul, pour construire un encodage de données programmable et à faible cout de bande passante, limité en disparité et en nombre de bits identiques consécutifs. / Thanks to their routing simplicity, noise, EMI (Electro-Magnetic Interferences), area and power consumption reduction advantages over parallel links, High Speed Serial Links (HSSLs) are found in almost all today's System-on-Chip (SoC) connecting different components: the main chip to its Inputs/Outputs (I/Os), the main chip to a companion chip, Inter-Processor Communication (IPC) and etc… Serial memory might even be the successor of current DDR memories.However, going from parallel links to high-speed serial links presents many challenges; HSSLs must run at higher speeds reaching many gigabits per second to maintain the same end-to-end throughput as parallel links as well as satisfying the exponential increase in the demand for throughput. The signal's attenuation over copper increases with the frequency, requiring more equalizers and filtering techniques, thereby increasing the design complexity and the power consumption.One way to optimize the design at high speeds is to embed the clock within the data, because a clock line means more routing surface, and it also can be source to high EMI. Another good reason to use an embedded clock is that the skew (time mismatch between the clock and the data lanes) becomes hard to control at high frequencies. Transitions must then be ensured inside the data that is sent on the line, for the receiver to be able to synchronize and recover the data correctly. In other words, the number of Consecutive Identical Bits (CIBs) also called the Run Length (RL) must be reduced or bounded to a certain limit.Another challenge and characteristic that must be bounded or reduced in the data to send on a HSSL is the difference between the number of ‘0' bits and ‘1' bits. It is called the Running Disparity (RD). Big differences between 1's and 0's could shift the signal from the reference line. This phenomenon is known as Base-Line Wander (BLW) that could increase the BER (Bit Error Rate) and require filtering or equalizing techniques to be corrected at the receiver, increasing its complexity and power consumption.In order to ensure a bounded Run Length and Running Disparity, the data to be transmitted is generally encoded. The encoding procedure is also called line coding. Over time, many encoding methods were presented and used in the standards; some present very good characteristics but at the cost of high additional bits, also called bandwidth overhead, others have low or no overhead but do not ensure the same RL and RD bounds, thus requiring more analog design complexity and increasing the power consumption.In this thesis, we propose a novel programmable line coding that can perform to the desired RL and RD bounds with a very low overhead, down to 10 times lower that the existing used encodings and for the same bounds. First, we show how we can obtain a very low overhead RL limited line coding, and second we propose a very low overhead method which bounds the RD, and then we show how we can combine both techniques in order to build a low overhead, Run Length Limited, and Running Disparity bounded Line Coding
150

Trilhas de comunicação científica : links de postagens de pesquisadores brasileiros nos blogs de ciência / Trails of scientific communication: links of posts of Brazilian researchers in science blogs

Sousa, Rodrigo Silva Caxias de January 2011 (has links)
O objetivo deste estudo consiste em interpretar o uso dos links nas postagens dos blogs de pesquisadores brasileiros. A investigação tem início através da análise dos links dos blogs inclusos no Anel de Blogs Científicos. Sua efetivação ocorre a partir da composição dos aglomerados das redes de links oriundas dos blogrolls, dos blogs de ciência circunscritos ao Anel de Blogs Científicos. Em momento posterior, foram categorizados os 640 links inclusos no conteúdo das postagens de acordo com as categorias de funções e motivações obtidas de estudos precedentes, e de categorias que emergiram do fenômeno estudado. Por fim, a compreensão das motivações para a inserção de links na composição das postagens dos blogs e as funções que esses links cumprem foi inferida através da Análise de Conteúdo dos contextos aos quais os links estavam inseridos, considerando os espaços aos quais o leitor é remetido a partir de sua ativação. Resultados indicam que o conceito de diários pessoais, em que as mensagens têm um número reduzido de caracteres e são apresentadas em ordem cronológica inversa, só se confirmam em relação a essa última característica, decorrente dos softwares de composição que assim a condicionam. A pouca incidência de links em relação aos blogs de pesquisadores permite afirmar que há uma baixa conectividade por parte dos blogs compostos por diferentes atores que compõem a amostra relativa ao Anel e às áreas as quais pertencem, reforçada pela baixa existência de links entre as postagens e os comentários. Reforça essa questão a ausência de links trackbaks entre os comentários das postagens selecionadas. A primeira das hipóteses que guia o estudo foi refutada, na medida em que as postagens não indicam rearticulações através de seus links de interlocuções entre pesquisadores, leigos e jornalistas científicos, não permitindo reordenações e maior amplitude dessas interlocuções junto à sociedade. A segunda das hipóteses foi confirmada por se basear no fato de que os links colocam em evidência que os documentos e fontes de informação relacionados a partir desses dispositivos (links) são um híbrido de uso e socialização de informações, estas tanto circunscritas às fontes e documentos científicos quanto a fontes e documentos que não se caracterizem tradicionalmente como parte do ciclo de produção científica. A terceira hipótese que guia este estudo foi refutada, pois os dados analisados indicam que o uso dos links por pesquisadores brasileiros não se baseia em funções e motivações que objetivam agilizar processos de produção e comunicação dos resultados de pesquisa através de blogs. / The aim of this study is to interpret the use of links on the blog postings by Brazilian researchers. The investigation begins by examining the links of blogs included in the Anel de Blogs Científicos (Ring of Science Blogs). Its effectiveness is based on the combination of clusters of link networks coming from the blogrolls restricted to the Anel de Blogs Científicos. Afterwards the 640 links included in the content of the posts were classified according to categories of functions and motivations obtained from previous studies and from categories that emerged from the phenomenon studied. Finally, understanding of motivations for the insertion of links on the composition of the blog posts and the functions that such links fulfill were inferred by Content Analysis of the contexts to which the links were inserted, considering the locations to which the reader is referred from its activation. Results indicate that the concept of personal journals, in which the messages have a limited number of characters and are presented in reverse chronological order, is only confirmed through this latter feature, as a result of the software used for composing the posts. The low incidence of links in relation to blogs of researchers allows us to state that there is low connectivity by blogs composed by different authors who form the sample relative to the Anel and the areas which they belong to, reinforced by the low availability of links between posts and comments. What reinforces this point is the absence of trackbak links among comments of the selected posts. The first hypothesis guiding the study was refuted, in that the posts do not indicate rearticulations through its links of dialogues among researchers, lay people and science journalists, not allowing rearrangements and higher amplitude of these dialogues with society. The second hypothesis was confirmed by relying on the fact that the links give evidence that the documents and related sources of information from those devices (links) are a hybrid of using and sharing of information – this information being limited to the sources and scientific documents as much as to sources and documents that are not traditionally characterized as part of the cycle of scientific production. The third hypothesis that guides this study was refuted because the data analyzed indicate that the use of links by Brazilian researchers is not based on functions and motivations that aim at streamlining production processes and communication of research results through blogs.

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