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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.
291

Obchodování s emisními povolenkami: analýza dosavadních efektů / Emissions Trading - Analysis Of Achievements

Perglerová, Eva January 2010 (has links)
This Master thesis analyses the European Union Emissions Trading Scheme (EU ETS). The aim is to analyse this instrument and its achievements. Emission allowances represent a new market instrument of the European Union's policy to reduce greenhouse gas emissions in order to combat the climate change. The first part of the thesis focuses on international climate negotiations, in particular on the Kyoto Protocol, which triggered the establishment of the EU ETS. The second part focuses on the system functioning and its achievements. The third part deals with the functioning of the EU ETS in the Czech Republic.
292

Meeting the minimum standards of the Palermo Protocol: The case of South Africa

Shepherd, Robyn January 2019 (has links)
Magister Legum - LLM / This research is aimed at evaluating the adequacy and effectiveness of the legal framework dealing with human trafficking in South Africa. To achieve this purpose, a comprehensive overview of the punishment, prevention of human trafficking in South Africa was looked into as well as victim protection. An overview of the history of slavery and an analysis of the modern conceptualisation of human trafficking indicate that human trafficking is a highly complex concept, and that there are various approaches to the understanding of the concept of human trafficking. There are various definitions of trafficking found in international instruments of which the most important has been identified as that contained in the Palermo Protocol. The definitions vary also because trafficking is closely related to the phenomena of migration, slavery and smuggling of humans. The study further identifies some significant root causes of trafficking The research concedes that although common-law crimes, statutes and transitional legislation can be utilized to challenge some trafficking elements, these offences are not comprehensive enough to amply deal with the crime’s complexities and provide only a fragmented approach to combating the crime. The study shows that South Africa has adopted specific legislation, namely the Trafficking Act. The research further establishes also that international, regional and sub-regional instruments on trafficking and related aspects of trafficking provide guidelines for developing effective strategies to deal with trafficking within the region. The counter-trafficking strategies as found in treaties, protocols, declarations and resolutions, which focus specifically on combating trafficking and those with a human-rights focus, obliges States to prosecute traffickers, protect those who are vulnerable to trafficking as well as those already trafficked and establish measures for prevention. This research further highlighted the importance of preventing human trafficking which starts with government but non- governmental organisations play a vital role in this element as well.
293

The development of palliative care protocols for the emergency and oncology nurses in the government hospitals of the Western Cape

February, Christine January 2019 (has links)
Philosophiae Doctor - PhD / Background: Palliative care is specialised health care to support people living with a terminal illness, and their families. Palliative care aims to prevent and relieve suffering, to help people to live as well as possible until they die, and to support the processes of dying and bereavement. Palliative care is holistic care provided by Emergency and Oncology Nurses caring for cancer patients. Palliative care protocols for Professional Nurses working in Emergency Units and Oncology Departments are not always posted or in full view in the government hospitals of the Western Cape. The researcher had noted that the development of a palliative care protocol would be unique in its use at the three targeted government hospitals. Aims and Objectives: This study focused on the development and implementation of palliative care protocols for Emergency and Oncology Nurses in the targeted government hospitals of the Western Cape, i.e., protocols could be beneficial for cancer patients and their families. The overall aim of the research was to develop applied palliative care protocols for Emergency and Oncology Nurses to provide best practice palliative care nursing for Oncology Patients who may present at any one of three Western Cape Provincial Hospitals.
294

Predicting Global Internet Instability Caused by Worms using Neural Networks

Marais, Elbert 16 November 2006 (has links)
Student Number : 9607275H - MSc dissertation - School of Electrical and Information Engineering - Faculty of Engineering and the Built Environment / Internet worms are capable of quickly propagating by exploiting vulnerabilities of hosts that have access to the Internet. Once a computer has been infected, the worms have access to sensitive information on the computer, and are able to corrupt or retransmit this information. This dissertation describes a method of predicting Internet instability due to the presence of a worm on the Internet, using data currently available from global Internet routers. The work is based on previous research which has indicated a link between the increase in the number of Border Gateway Protocol (BGP) routing messages and global Internet instability. The type of system used to provide the prediction is known as an autoencoder. This is a specialised type of neural network, which is able to provide a degree of novelty for inputs. The autoencoder is trained to recognise “normal” data, and therefore provides a high novelty output for inputs dissimilar to the normal data. The BGP Update routing messages sent between routers were used as the only inputs to the autoencoder. These intra-router messages provide route availability information, and inform neighbouring routers of any route changes. The outputs from the network were shown to help provide an early warning mechanism for the presence of a worm. An alternative method for detecting instability is a rule-based system, which generates alarms if the number of certain BGP routing messages exceeds a prespecified threshold. This project compared the autoencoder to a simple rule-based system. The results showed that the autoencoder provided a better prediction and was less complex for a network administrator to configure. Although the correlation between the number of BGP Updates and global Internet instability has been shown previously, this work presents the first known application of a neural network to predict the instability using this correlation. A system based on this strategy has the potential to reduce the damage done by a worm’s propagation and payload, by providing an automated means of detection that is faster than that of a human.
295

Methodological assessment of the Critical Thermal Maximum (CTmax) of anuran larvae: interaction among the experimental heating rates, ontogeny and body mass / Estudo metodológico da Temperatura Crítica Máxima (CTmax) de larvas de anfíbios anuros: interação entre as taxas de aquecimento experimental, ontogenia e massa corpórea

Cantero, Gustavo Adolfo Agudelo 31 October 2016 (has links)
Thermal limits for ectothermic animals displays a picture of the range of body temperatures that is tolerable by individuals before their locomotory capacity is impaired. However, thermal limits are not fixed and specific traits, but labile ones subjected to plastic adjustments and evolutionary change, and also are influenced by intrinsic and extrinsic factors of organisms, as well as by methodological factors inherent to experimental protocols. Even more, the influences of these factors on thermal limits have been commonly addressed independently in different taxa, and the extent by which multiple factors interact and affect thermal limits within taxa is poorly understood. Thus, the main aim of this work was to conduct a methodological assessment of the Critical Thermal Maximum (CTmax) by studying the influences of different experimental heating rates (ΔT’s), ontogeny, body mass, and the interaction among these factors on this trait. This matter was addressed on larvae of Physalaemus nattereri and Hypsiboas pardalis, two anuran species from the São Paulo State, southeastern Brazil, that differ in their phylogenetic background, ecological and life-history characteristics and inhabit environments with different thermal regimes. First, ΔT’s did affect averages and variances of CTmax in a species-specific manner. In addition, it was found a ΔT-dependent decreasing in CTmax at the end of metamorphosis in tadpoles of P. nattereri, because only the metamorphosing tadpoles exposed to the acute ΔT were more sensitive to high temperature than premetamorphic tadpoles. Finally, body mass and ΔT’s interacted on the CTmax of both species along our experimental design. In P. nattereri, body mass affected CTmax through physiology at the slow ΔT’s, whereas in H. pardalis body mass affected CTmax at the acute ΔT through a methodological artifact driven by higher thermal inertia in the group of large tadpoles. This study revealed that ΔT’s, ontogeny and body mass interact on the CTmax of our studied species, and these interactive effects could not have been elucidated by the independent study of each factor. It also highlights the importance of integrating the factors that influence thermal limits of ectothermic animals, especially in the context of climate change / Os limites térmicos para animais ectotérmicos mostram uma imagem do intervalo de temperaturas corporais que é tolerável pelos indivíduos antes de sua capacidade locomotora ser prejudicada. Porém, os limites térmicos não são características fixas e específicas, mas traços lábeis sujeitos tanto a ajustes plásticos quanto a mudanças evolutivas, e são influenciados por fatores intrínsecos e extrínsecos dos organismos, e também por fatores metodológicos associados aos protocolos experimentais. Ainda mais, as influências desses fatores sobre os limites térmicos têm sido comumente abordadas de forma independente em diferentes espécies, e o grau pelo qual múltiplos fatores interagem e afetam os limites térmicos dentro das espécies é pouco compreendido. Assim, o principal objetivo deste trabalho foi conduzir uma avaliação metodológica da Temperatura Crítica Máxima (CTmax) estudando as influências de diferentes taxas de aquecimento experimental (ΔT’s), ontogenia, massa corpórea e a interação entre esses fatores sobre esta característica fisiológica. Este assunto foi abordado em larvas de Physalaemus nattereri e Hypsiboas pardalis, dois espécies de anfíbios anuros encontrados no Estado de São Paulo, sudeste do Brasil, que diferem em sua origem filogenética, características ecológicas e de história de vida, e também habitam ambientes com diferentes regimes térmicos. Primeiro, foi encontrado que as ΔT’s afetaram tanto os valores médios quanto as variâncias da CTmax em ambas as espécies de maneira específica. Além disso, achou-se uma diminuição em CTmax no final da metamorfose que foi dependente da ΔT em larvas de P. nattereri, dado que nessa espécie só os girinos em metamorfose que foram expostos à ΔT aguda foram mais sensíveis às altas temperaturas do que os girinos premetamórficos. Finalmente, a massa corpórea e as ΔT’s interagiram sobre a CTmax em ambas as espécies ao longo do desenho experimental. Em P. nattereri, o efeito da massa corpórea sobre a CTmax foi fisiológico nas ΔT’s lentas, enquanto que em H. pardalis o efeito da massa corpórea na ΔT aguda foi devido a um artefato metodológico causado por maior inércia térmica no grupo de girinos maiores. Este estudo revelou que as ΔT’s, a ontogenia e a massa corpórea interagem sobre a CTmax das espécies estudadas, e estes efeitos interativos não poderiam ter sido elucidados pelo estudo independente de cada fator. Também é salientada a importância de integrar os fatores que influenciam os limites térmicos dos animais ectotérmicos, especialmente no contexto das mudanças climáticas
296

Cifra multicanal para maior segurança em redes TCP /IP / Multichannel cipher for higher TCP/IP security

Azevedo Neto, Sylvio Ximenez de 30 October 2013 (has links)
Neste documento apresentamos uma cifra multicanal inspirada nas técnicas de telecomunicações de espalhamento espectral (Spread Spectrum), ou como também conhecido, difusão espectral, para prevenir escuta em uma rede de computadores TCP/IP. Mostramos que dividindo um texto-ilegível ciphertext em blocos de tamanho fixo e transmitindo-os aleatoriamente através de diversos canais estabelecidos entre os agentes (transmissor - receptor) é possível aumentar a complexidade da criptanálise por um suposto adversário não autorizado que esteja escutando a comunicação, dessa forma aumentando relativamente a segurança. Mostramos teoricamente que o tempo de quebra da cifra multicanal cresce em ordem fatorial ou exponencial em função do número de canais utilizados na comunicação. Além disso, adaptado a um esquema de difusão binária herdado do AES (Advanced Encryption Standard) é possível incrementar a segurança da cifra multicanal para maior resiliência contra a criptanálise diferencial. / In this work we present a multichannel cipher inspired on telecommunications Spread Spectrum techniques to prevent eavesdropping in a TCP/IP network. We show that splitting any ciphertext into fixed size blocks and sending them randomly through multiple channels established between the agents (transmitter and receiver) it is possible to increase the complexity of cryptanalysis by a supposed not authorized adversary that might be eavesdropping the communication, in this way, relatively increasing the security. We show theoretically that the brake time of multichannel cipher grows in factorial or exponential order, in function of the number of channel used in the communication. Moreover adapted to binary spread scheme inherited from AES (Advanced Encryption Standard) it is possible to increase the cipher security for more resilience against differential cryptanalysis.
297

Procedimento para uniformização de espectros de solos (VIS-NIR-SWIR) / Proceeding for standardization of soils spectra (VIS-NIR-SWIR)

Romero, Danilo Jefferson 04 December 2015 (has links)
As técnicas de sensoriamento remoto têm evoluído dentro da ciência do solo visando superar as limitações de tempo e custo das análises químicas tradicionalmente utilizadas para quantificação de atributos do solo. As análises espectrais há muito tempo têm provado serem alternativas para complementar às análises tradicionais, sendo consideradas atualmente uma técnica consolidada e de ampla utilização. Os estudos em pedologia espectral têm utilizado os comprimentos de onda entre 350 a 25000 nm, porém, têm se detido com mais frequência na região de 350 a 2500 nm, a qual é dividida em Visível (VIS - 350 a 700 nm), infravermelho próximo (NIR - 700 a 1000 nm), e infravermelho de ondas curtas (SWIR - 1000 até 2500 nm). A exemplo das técnicas laboratoriais tradicionalmente utilizadas em análises de solos, faz-se necessário estabelecer padrões visando a comunicação científica a nível mundial em espectroscopia de solos. Com vista ao futuro da espectroscopia de solos, desenvolveu-se este estudo afim de se avaliar o efeito do uso de amostras padrões na aquisição de dados espectrais de amostras de solos tropicais em três diferentes geometrias de aquisição em três espectrorradiômetros (350 - 2.500 nm). 97 amostras de solos registrados na Biblioteca Espectral de Solos do Brasil (BESB) provenientes do Estado do Mato Grosso do Sul, cedidas pelo projeto AGSPEC foram utilizadas no estudo e duas amostras mestre brancas utilizadas como padrões de referência, sendo estas oriundas das dunas das praias de Wylie Bay (WB - 99 % quartzo) e Lucky Bay (LB - 90 % quartzo e 10 % aragonita), no sudoeste da Austrália. Para avaliar a padronização, as morfologias das curvas espectrais foram observadas quanto curvatura, feições, albedo; complementando as observações descritivas, as diferenças de reflectância entre os tratamentos utilizados (Sensor x Geometria x Correção) foram estudadas pela análise de variância e pelo teste de Tukey a 5 % de significância em três bandas espectrais médias (VIS-NIR-SWIR); e a modelagem para quantificação de teores de argila por meio da regressão por mínimos quadrados parciais (\"partial least squares regression\", PLSR), com validação cruzada (Cross Validation) para cada configuração e outra simulando uma biblioteca espectral mista, composta por combinações entre as configurações. O método de padronização proposto reduz as diferenças entre espectros obtidos em diferentes sensores e geometrias. A predição de argila por uma biblioteca espectral utilizando dados com diferentes configurações é favorecida pela padronização, passando de um de 0,83 para um de 0,85 após a correção, indicando a validade da unificação dos espectros pela técnica proposta. / Remote sensing techniques have evolved within the soil science aiming to overcome time and cost limitations of chemical analysis traditionally used for quantification of soil properties. Spectral analysis have long proven to be alternatives to supplement traditional analysis, currently being considered a mature technique and widely applied. Studies on spectral pedology have used the wavelength between 350 to 25000 nm, however, have held more often in the region of 350 to 2500 nm, which is divided into visible (VIS - 350 to 700 nm), near infrared ( NIR - 700 to 1000 nm) and short wave infrared (SWIR - 1000 to 2500 nm). As traditional laboratory techniques used in soil analysis, it is necessary to establish standards aimed at worldwide scientific communication in soils spectroscopy. Going forward soil spectroscopy, this study was developed in order to evaluate the effect of using standard samples in the acquisition of spectral data of tropical soil in three different geometries acquisition in three spectroradiometers (350-2500 nm). 97 soil samples documented in Brazilian Soils Spectral Library (BESB) from Mato Grosso do Sul State, provided by the AGSPEC project were used in the study and two white master samples used as reference standards, which are from the beaches dunes of Wylie Bay (WB - 99% quartz) and Lucky Bay (LB - 90% quartz and 10% aragonite) in southwestern Australia. To judge the standardization, the morphologies of the spectral curves were observed for curvature, absorption features, albedo; complementing the descriptive observations, the reflectance differences between the configurations (Sensor x Geometry x Correction) were studied by analysis of variance and Tukey test at 5% significance in three average spectral bands (VIS-NIR-SWIR); and modelling for quantification of clay through regression by partial least squares (PLSR) with cross-validation for each configuration and another simulating a mixed spectral library, consisting of combinations of situations. The method proposed standardization reduces differences between spectra obtained from different sensors and geometries. The prediction of clay by a spectral library using data with different settings is favoured to standardize, from R² of 0.83 to 0.85 after correction, indicating the validity of the unification of the spectra by the proposed technique.
298

Reflorestamento no Brasil e o Protocolo de Quioto / Reforestation in Brazil and the Kioto Protocol

Scarpinella, Gustavo D'Almeida 24 June 2002 (has links)
A questão das mudanças climáticas vem ganhando destaque e sendo mais discutida à medida que se caminha para a ratificação do Protocolo de Quioto. No presente trabalho é analisada a viabilidade de um projeto de reflorestamento candidato ao Mecanismo de Desenvolvimento Limpo, mecanismo de flexibilização proposto pelo Protocolo que permite a participação brasileira. São discutidos aspectos favoráveis e desfavoráveis à implementação de um projeto florestal, nas condições atuais. Para tal discussão propõe-se uma atividade de reflorestamento com espécies do gênero Eucalyptus, administrada por uma cooperativa florestal dentro da regional agrícola de Botucatu (SP). Os objetivos principais desta atividade são a obtenção de madeira para fins de serraria e a comercialização de créditos de carbono referentes ao volume de madeira serrada. Foram feitos cálculos de viabilidade econômica pela Taxa Interna de Retorno (TIR) e pelo Valor Presente Líquido (VPL) do projeto, com e sem o emprego do MDL. Verificou-se a viabilidade econômica nos dois casos, embora a diferença na receita não tenha sido considerável. Em projetos em que não há a participação do MDL, a TIR média foi de 7% para todas as áreas. Com a participação do MDL, houve uma variação da TIR de 6,2% a 7,3%, conforme as extensões das áreas adotadas e os preços pagos pela tonelada do carbono. Para pequenas áreas, o emprego do MDL pode inviabilizar o projeto. As atividades florestais para fins de serraria mostraram um rendimento muito baixo para o MDL, pelo fato de apenas um décimo da produção total ser aceito para comercialização dos créditos de carbono. / The issue of climate change wins relevance and brings controversy as the ratification of Kyoto Protocol approaches for most countries. Present work analyses feasibility for a reforesting project candidate for the Clean Development Mechanism (CDM). CDM is a flexibilization mechanism proposed in the Protocol wich allows Brazilian participation. Both favorable and unfavorable aspects are discussed for the implementation of a forest project under present conditions. For the purpose of this discussion, an activity of reforestation based on trees of the Eucalyptus species, managed by a forest cooperative society, in the agricultural region of Botucatu (SP). Main goal for such cooperative are obtained of lumber and commercialization of carbon credits relative to the quantity of lumber produced. Calculations for economic feasibility were carried out, producing the Internal Rate of Revenue (IRR) and the Present Net Worth (PNW), both under and out of the CDM. Economical feasibility were confirmed for both cases, although difference between revenues was not considerable. For projects with no CDM participation, average IRR was 7,0 per cent for all area extents. With CDM participation, the was a rate range between 6,2 and 7,3 per cent, according to the extent of submitted areas, and prices paid for ton of carbon. For small areas, CDM adoption can turn the project unfeasible. Forest activities for producing lumber showed low profitability for CDM, due to the fact that only one tenth of total production is accepted for commercialization of carbon credits.
299

SACK TCPVENO: an enhanced version of SACK TCP. / SACK TCP VENO

January 2001 (has links)
by Chung Ling Chi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 74-76). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Overview --- p.1 / Chapter 1.2 --- Motivation and Proposed Solution --- p.2 / Chapter 1.3 --- Organization of the Thesis --- p.4 / Chapter Chapter 2 --- Background --- p.5 / Chapter 2.1 --- Basics of Transmission Control Protocol --- p.5 / Chapter 2.1.1 --- Slow Start and Congestion Avoidance --- p.5 / Chapter 2.1.2 --- Fast Retransmit and Fast Recovery --- p.7 / Chapter 2.2 --- SACK TCP Mechanism --- p.8 / Chapter 2.2.1 --- SACK-permitted Option during Three-way Handshake --- p.8 / Chapter 2.2.2 --- SACK blocks in SACK Option --- p.9 / Chapter 2.2.3 --- Interpreting the SACK Option using Scoreboard --- p.10 / Chapter 2.2.4 --- Retransmission Strategy --- p.11 / Chapter 2.3 --- TCP Veno Mechanism --- p.13 / Chapter 2.3.1 --- Refined Additive Increase --- p.13 / Chapter 2.3.2 --- Refined Multiplicative Decrease --- p.14 / Chapter Chapter 3 --- SACK TCPVeno --- p.16 / Chapter 3.1 --- Distinguishing between Types of Packet Loss --- p.17 / Chapter 3.2 --- Refined Multiplicative Decrease --- p.21 / Chapter 3.2.1 --- Algorithm --- p.21 / Chapter 3.2.2 --- Recovery in Consecutive packet Losses --- p.22 / Chapter 3.2.3 --- Recovering Multiple Packet Losses within a Single Window --- p.26 / Chapter 3.3 --- Refined Additive Increase --- p.37 / Chapter 3.3.1 --- Algorithm --- p.37 / Chapter 3.3.2 --- Advantages --- p.40 / Chapter 3.4 --- Other Issues --- p.43 / Chapter 3.4.1 --- Two Side Modifications --- p.43 / Chapter Chapter 4 --- Experiments --- p.44 / Chapter 4.1 --- The Network Scenario --- p.44 / Chapter 4.1.1 --- Dummynet --- p.45 / Chapter 4.2 --- Experiment Results --- p.47 / Chapter 4.2.1 --- Single Connection --- p.47 / Chapter 4.2.1.1 --- Congestion Window Evolution --- p.47 / Chapter 4.2.1.2 --- Sending Rate and Throughput Evolution --- p.49 / Chapter 4.2.1.2.1 --- Impact of Packet Loss Rate Due to Lossy Link --- p.49 / Chapter 4.2.1.2.2 --- Impact of Buffering --- p.52 / Chapter 4.2.1.2.3 --- Impact of Propagation Delay --- p.57 / Chapter 4.2.2 --- Multiple Connections --- p.62 / Chapter 4.2.2.1 --- Fairness --- p.62 / Chapter 4.2.2.2 --- Compatibility --- p.67 / Chapter Chapter 5 --- Conclusion --- p.72 / Bibliography --- p.74
300

On secure messaging

Cohn-Gordon, Katriel January 2018 (has links)
What formal guarantees should a secure messaging application provide? Do the most widely-used protocols provide them? Can we do better? In this thesis we answer these questions and with them give a formal study of modern secure messaging protocols, which encrypt the personal messages of billions of users. We give definitions and analyses of two protocols: one existing (Signal) and one new (ART). For Signal, we begin by extending and generalising classic computational models, in order to apply them to its complex ratcheting key derivations. With a threat model in mind we also define a security property, capturing strong secrecy and authentication guarantees including a new one which we call "post-compromise security". We instantiate Signal as a protocol in our model, stating its security theorem and sketching a computational reduction. Signal only supports encrypting messages between two devices, and so most implementers have built custom protocols on top of it to support group conversations. These protocols usually provide weaker security guarantees, and in particular usually do not have post-compromise security. We propose a new protocol called ART, whose goal is to bring Signal's strong security properties to conversations with multiple users and devices. We give a design rationale and a precise definition of ART, and again generalise existing computational models in order to formally specify its security properties and sketch a security reduction. ART has enjoyed widespread interest from industry, and we aim to turn it into an open standard for secure messaging. To that end, we have brought it to the IETF and formed a working group called Messaging Layer Security, with representatives from academia as well as Facebook, Google, Twitter, Wire, Cisco and more. Through MLS, we hope to bring ART's strong guarantees to practical implementations across industry. After concluding our analyses we pause for a moment, and start looking towards the future. We argue that for complex protocols like Signal and ART we are reaching the limits of computational methods, and that the future for their analysis lies with symbolic verification tools. To that end we return to the symbolic model and give a number of case studies, in each one showing how a traditional limitation of symbolic models can in fact be seen as a modelling artefact.

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