• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 379
  • 143
  • 55
  • 51
  • 37
  • 35
  • 18
  • 8
  • 7
  • 6
  • 4
  • 4
  • 4
  • 4
  • 4
  • Tagged with
  • 884
  • 188
  • 121
  • 92
  • 87
  • 67
  • 63
  • 63
  • 58
  • 49
  • 47
  • 46
  • 44
  • 44
  • 43
  • 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

Radialinių bazinių funkcijų neuroninių tinklų taikymas daugiamačiams duomenims vaizduoti / Visualization of the multidimensional data by using the radial basis function neural networks

Vengrovskij, Artiom 16 August 2007 (has links)
Neuroniniai tinklai ypatingi tuo, kad juos galima apmokyti. Radialinių bazinių funkcijų neuroniniai tinklai naudojami kaip aproksimavimo funkcijos atpažįstant objektus ir apdorojant signalus. Norint gerai vizualizuoti daugiamačius duomenis radialinių bazinių funkcijų neuroniniais tinklais, daug kas priklauso nuo to, kokie metodai bus parenkami geram rezultatui gauti ir į kokius duomenis atsižvegiant bus vizualizuojami analizuojami įėjimo duomenys (pavyzdžiui, pagal svorius, ar pagal bazinių funkcijų reikšmes). Darbe yra detaliai ištirti radialinių bazinių funkcijų (RBF) neuroniniai tinklai bei šio metodo galimybės duotiems taškams vizualizuoti. Darbo uždavinys — sukurti radialinių bazinių funkcijų neuroninių tinklų algoritmą daugiamačiams duomenims vizualizuoti. Tinklo apmokymui buvo parinkti efektyvūs metodai bazinės funkcijos parametrams rasti. Kompiuteriniams eksperimentams atlikti naudotas MATLAB programinis paketas. Atlikta algoritmo lyginamoji analizė pagal šiuos aspektus:  svorius;  bazinių funkcijų gautas reikšmes;  vizualų duomenų projekcijų įvertinimą. Radialinių bazinių funkcijų neuroninių tinklų efektyvumas labai priklauso nuo bazinių funkcijų centrų parinkimo. Darbe atskleistos naujos galimybės greitam daugiamačių duomenų vizualizavimui plokštumoje ir erdvėje. Tai sudaro pagrindą tolesniems tyrimams šioje duomenų analizės srityje. / Neural networks are special, because they can “learn“. Radial Basic Function Type Neural Networks are used as functions for approximation in object recognition and signal processing. When trying to achieve good visualization of data by using RBFN, a lot depends on the methods used to achieve this result and the data, used to visualize and analyze input data (e.g. by weight or by basic function values). This thesis contains detailed analysis of Radial Basic Function (RBF) neural networks and the possibilities of this method to visualize the given points. The task of this thesis is to explore the possibility of RBF application in visualization of multidimensional data. For network "education", the effective methods for finding basic function parameters were chosen. Computer experiments where conducted with MATLAB software. A comparative analysis of the algorithm was performed according to the following aspects:  weights;  values, obtained by basic functions;  visual evaluation of data projections. Efficiency of RBFN depends greatly on selection of the centers of basic functions. The research showed, that RBNF can be successfully applied in multidimensional data visualization. Thesis gives new possibilities for displaying multidimensional data on a plane and in space. This serves as a background for future researches in this field of data analysis.
112

A radial basis memory model for human maze learning

Drewell, Lisa Y. 30 June 2008 (has links)
This research develops a memory model capable of performing in a human-like fashion on a maze traversal task. The model is based on and retains the underlying ideas of Minerva 2 but is executed with different mathematical operations and with some added parameters and procedures that enable more capabilities. When applied to the same maze traversal task as was used in a previous experiment with human subjects, the performance of a maze traversal agent with the developed model as its memory emulated the error rates of the human data remarkably well. As well, the maze traversal agent and memory model successfully emulated the human data when it was divided into two groups: fast maze learners and slow maze learners. It was able to account for individual differences in performance, specifically, individual differences in the learning rate. Because forgetting was not applied and therefore all experiences were flawlessly encoded in memory, the model additionally demonstrates that error can be due to interference between memories rather than forgetting. / Thesis (Master, Computing) -- Queen's University, 2008-06-04 13:39:38.179
113

The challenges of working and studying at a satellite campus : a case study of the Riverside Campus of the Durban University of Technology

Gumede, Dumsile Cynthia 13 June 2014 (has links)
Submitted in fulfillment for the Degree of Doctor of Technology: Business Administration, Durban University of Technology, 2014 / Universities are seen to be facing a turbulent storm of challenges, demands, environmental changes, and facilitated thrust in the midst of economic meltdown. The environments in which these institutions are operating are becoming increasingly tempestuous, and competitive which makes leadership crucial as they continuously interface with the local and wider environments. At its best leadership is proximate, contextual and distributed especially in the case of complex organisations like universities. Changes and institutional mergers that took place worldwide two decades ago diffused to the south of Africa as well. These mergers resulted in the formation of mega universities and universities with satellite or branch campuses. If the trend continues with branch campuses spreading even into foreign countries, it will lead to growth and even more leadership complexity. This study was conducted in order to establish the challenges that are faced by staff and students at satellite campuses of universities using the Riverside Campus of the Durban University of Technology as a case study. Literature on leadership and management theories, leadership in higher education and organisational structures was reviewed in order to contextualise the study. A sample of the executive leadership of the university used as a case study was interviewed in order to determine their attitudes towards the current organisational structure. Data was also gathered from the academic and administrative staff at the satellite campus used for the study as well as first and third year students at the same campus using questionnaires. This study is significant because it feeds into the year-long study that was initiated by the Leadership Foundation on Higher Education and conducted from 2010 and finished in July 2011 by the Hull University’s Scarborough Campus that was aimed at determining the most effective relationship between the centre (mother campus) and its satellite campuses, identifying tensions between the strategic and operational levels and making students’ experience consistent. The whole project was undertaken to arrive at a better understanding of the challenges of managing two or more campuses with particular emphasis on strategic matters, organisation, leadership and management structures. The study discovered that there were leadership challenges which were not unique to the university and campus used as a case study, but similar to those identified during literature review. Issues such as lack of leadership and strategic direction, diverse cultures, incomplete merger, isolation, inequitable distribution of resources and lack of development were identified as challenges that needed to be addressed. The study advances as original contribution the ‘Radial Structure’, which was greatly inspired by the natural movement, flow and distribution of energy and information in fractals. This structure ensures equity across all campuses irrespective of size and location. In the radial structure as suggested and implied by the name the corporate division is the source of energy in the form of vision, mission, goals, strategy, and resources which it disburses or radiates equitably across all the campuses. The corporate division is not attached to any campus, but it is a pole that provides an anchor for all the campuses. The energy or feedback is also radiated back to the corporate office from the campuses in the form of student fees, research output from staff and students, pass rates, information to aid decision-making and so on. The relationship that was established between the radial structure and the regression model developed from the responses of the students and theory, was that each campus should be fully-equipped with all the services that the users require for the campus to be fit for purpose. The radial structure would also allow for student services to grow and develop as the campus grows. Like any organisational structure, the radial structure could be adjusted to suit the needs of any university with satellite campuses. The organisational structure would also have to be revisited and adjusted as the needs of the university change. In essence the structure is aimed at ensuring that there is no leadership vacuum at any of the satellite campuses of a university.
114

Analytic singularities near radial points

Zheng, Jiguang 12 December 2014 (has links)
No description available.
115

Neuronal Migration and Neuronal Migration Disorder in Cerebral Cortex

SUN, Xue-Zhi, TAKAHASHI, Sentaro, GUI, Chun, ZHANG, Rui, KOGA, Kazuo, NOUYE, Minoru, MURATA, Yoshiharu 12 1900 (has links)
国立情報学研究所で電子化したコンテンツを使用している。
116

Humeral shaft fractures : epidemiology and outcome /

Ekholm, Radford, January 2007 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.
117

Desenvolvimento de método para medição da força radial em endopróteses aórticas

Nogueira, Ana Paula Gomes January 2011 (has links)
O desempenho das endopróteses vasculares está relacionado diretamente à sua força radial. Esta é uma importante propriedade mecânica destes dispositivos médicos, influenciada por características da matéria-prima, pelos parâmetros de processamento empregados e pela morfologia do produto. Em um ensaio de força radial, determina-se a força necessária para comprimir e para expandir uma endoprótese, ou seja, em função da variação do seu diâmetro é medida a força envolvida. Uma característica desejada nestes ensaios é que a endoprótese se comprima e se expanda de forma homogênea, mantendo sempre sua seção na forma circular, condição esta que a maioria dos métodos hoje utilizados não atende. O presente trabalho buscou desenvolver um método para ser utilizado na determinação da força radial de endopróteses aórticas. Para tanto, um dispositivo composto por uma cinta polimérica acoplada a uma máquina universal de ensaios foi criado. Para verificar a manutenção da forma circular da endoprótese, imagens foram obtidas no decorrer do ensaio. Os resultados mostraram que o dispositivo desenvolvido é capaz de manter a forma circular das endopróteses durante todo o ensaio. Para examinar a capacidade do dispositivo em detectar diferenças nas forças radiais apresentadas por endopróteses em diferentes condições, foram realizados dois estudos, um variando o diâmetro dos fios (0,2, 0,3 e 0,4 mm) utilizados na fabricação das endopróteses e outro variando o tempo de tratamento térmico (30, 45 e 60 min) das endopróteses. Sabendo-se também que as propriedades elásticas da matéria-prima (Nitinol) têm relação direta com a força radial que as endopróteses apresentam, os resultados dos testes de força radial das amostras foram confrontados com ensaios mecânicos de carregamento e descarregamento nos fios da matéria-prima. Os resultados indicaram que o dispositivo foi capaz de detectar diferenças entre valores de força radial com amostras em diferentes condições (tanto de diâmetro de fio como de tratamento térmico) e que os resultados obtidos foram coerentes com testes de carregamento e descarregamento realizados nas amostras de matéria-prima. / The performance of vascular endoprosthesis is directly related to their radial force that is an important mechanical property of these medical devices. It is influenced by characteristics of the raw materials, the processing parameters and the morphology of the final product. The load necessary to compress and expand an endoprostheses is determined by a radial force test, which the load involved is measured by variation of its diameter. A characteristic required during these tests is homogenous compression and expansion of the endoprostheses maintaining its diameter value, in which most methods do not attend it. The aim of this study was develop a method to determine the radial force of aortic endoprostheses. Thus, a device composed with polymer film-type connected a universal test machine was created. Results showed that device developed is able to maintain the circular section (diameter) of the endoprostheses after test. Two studies were performed in order to check the devices’s ability and detect differences in radial forces of the endoprosthesis produced by different conditions. The first condition presented the varying of the wire diameter (0.2, 0.3 and 0.4mm), that was used in the production of the endoprosthesis, and the second one showed different times of heat treatment (30, 45 and 60 min). It is also well known that the elastic properties of the raw material (Nitinol) are directly related to the radial force presented by endoprosthesis. So, samples were compared with wire loading and unloading mechanical tests. Results indicated that the device was able to detect difference among values of radial force in samples at different conditions (both wire diameter and heat treatment time) and they showed consistence of loading and unloading tests performed on samples of raw material.
118

Modelagem Direta de Integrais de Domínio Usando Funções de Base Radial no Contexto do Método dos Elementos de Contorno

CRUZ, A. L. 19 October 2012 (has links)
Made available in DSpace on 2016-08-29T15:32:58Z (GMT). No. of bitstreams: 1 tese_6025_Dissertação Átila - Versão Final.pdf: 1436289 bytes, checksum: d082be19a6c6e491c7faa660452e547b (MD5) Previous issue date: 2012-10-19 / A pesquisa envolvida na presente dissertação se baseou no uso de funções de base radial para gerar uma nova formulação integral, que interpola diretamente o termo não homogêneo da equação diferencial de governo, no contexto do Método dos Elementos de Contorno (MEC). Propos-se o uso de funções primitivas das funções de interpolação originais no núcleo da integral de domínio, permitindo a transformação desta última numa integral de contorno, evitando assim a discretização do domínio por meio de células. Para melhor avaliação das potencialidades da formulação, os testes numéricos apresentados abordaram apenas a solução de problemas governados pela Equação de Poisson. Os problemas escolhidos dentro desta categoria possuem solução analítica, o que permitiu aferir com mais rigor a precisão dos resultados. Para melhor balizamento da eficiência da formulação proposta, todos os problemas abordados também foram resolvidos pela formulação com Dupla Reciprocidade. O custo computacional dispendido para cada uma dessas formulações também foi comparado. Para ambas as formulações também foram testados esquemas de ajuste da interpolação realizada, visando avaliar seus efeitos na precisão dos resultados e também propositando obter economia computacional em futuras aplicações em simulações na área de propagações de ondas. Palavras-chave: Método dos Elementos de Contorno, Funções de Base Radial, Equação de Poisson
119

Alocação ótima de bancos de capacitores em sistemas de distribuição radiais /

Segura Salas, Cresencio Silvio January 2006 (has links)
Orientador: Rubén Augusto Romero Lázaro / Banca: José Roberto Sanches Mantovani / Banca: Geraldo Roberto Martins da Costa / Resumo completo, clicar acesso eletrônico abaixo. / Mestre
120

Origem, ramificação e distribuição fascicular do nervo radial no braço do gato doméstico (Felis catus domesticus, Linnaeus, 1758) /

Guimarães, Gregório Corrêa. January 2004 (has links)
Orientadora: Márcia Rita Fernandes Machado / Banca: André Luiz Quagliatto Santos / Banca: Marcos Lania de Araújo / Resumo: Estudou-se a origem, a distribuição e a ramificação do nervo radial de 35 gatos domésticos adultos, 17 machos e 18 fêmeas, sem raça definida, mediante dissecações macro e mesoscópicas, após a fixação dos espécimes em solução aquosa de formaldeído a 10 %, e também realizou-se o exame histológico do referido nervo. O nervo radial mostrou-se polifasciculado desde sua origem até a divisão em ramos superficial e profundo. Originou-se do C6 ao T1 em 30 % dos exemplares e do C7 ao T1 em 70 % dos exemplares. Cedeu ramos musculares em todos os animais para os músculos tensor da fáscia antebraquial, tríceps braquial (cabeças longa, acessória, medial e lateral) e ancôneo, emitindo de 14 a 25 ramos nervosos nesta região. O ramo ventral do sexto nervo espinhal cervical difere significativamente (p<0,05) quando confrontado o sexo dos animais, além dos fascículos nervosos, de acordo com a região estudada. A estrutura histológica do nervo radial exibe três tecidos conjuntivos de sustentação. O epineuro é formado por tecido conjuntivo denso modelado e não modelado, e também por conjuntivo frouxo. Do epineuro partem septos epineurais, constituídos por conjuntivo denso não modelado e frouxo, rico em células adiposas. O perineuro reveste grupo de feixes nervosos formando os fascículos, possuindo de duas a quinze células justapostas concêntricas com núcleo fusiforme, citoplasma fino e alongado, diferenciando duas camadas, uma externa e outra interna. O espaço interlaminar da camada externa é preenchido por fibrilas colágenas e o da camada interna por fibrilas colágenas e reticulares. O endoneuro é constituído por tecido conjuntivo frouxo que circunda axônios predominantemente mielinizados, apresentando fibras colágenas e reticulares. / Abstract: The origin, distribution and ramification of the radial nerve was studied in thirty-five(35) adult unknown domestic cats from both sexes(18 females and 17 males). The samples were fixed in 10 % formaldehyde solution. There were made macroscopical and mesoscopical dissections and a histological examination of the radial nerve. The radial nerve revealed itself polifasciculated from its origin until his division in superficial branch and deep branch. In 30 % of the samples the radial nerve starts from the C6 until the T1 and from the C7 until the T1 in 70 % of the samples. In all animals studied the radial nerve lends muscular branches to the m. tensor fasciae antebrachii, to the m. triceps brachii (long head, accessory head, medial head and lateral head) and the m. anconeus, emitting from 14 to 25 nervous branches in this region. Besides, according to the studied region, the nervous fascicules and the ventral branch of the sixth cervical spinal nerve differs significantly (p<0.05) between males and females. The histological structure of the radial nerve has three conjunctive tissues for sustentation. The epineurium is formed by dense modeled conjunctive tissue and by dense non-modeled conjunctive tissue and also by loose conjunctive tissue. Epineural septum break up from the epineurium. They are rich in adipose cells and are formed by dense non-modeled conjunctive tissue and by loose conjunctive tissue. The perineurium revests a group of nervous bundles. The perineurium has from two to fifteen juxtaposed cells. These cells are concentric and they have a fusiform nucleus, a thin and prolonged cytoplasm that is divided in two layers-an external and an internal. The interlaminar space is filled by collagen fibers in the external layer and by collagen and reticular fibers in the internal layer. The endoneurium is formed by loose conjunctive tissue that embraces predominantly myelinated axons...(Complete abstract, click electronic access below) / Mestre

Page generated in 0.0368 seconds