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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.
1051

Dinâmica ecohidrológica de rios urbanos no contexto de gestão de riscos de desastres / Ecohydrological dynamics of urban rivers in the context of disaster risk management

Gustavo Bueno Romero 06 May 2016 (has links)
A expansão do tecido urbano e o adensamento das cidades têm um impacto negativo sobre os recursos hídricos, tanto na quantidade quanto na qualidade das águas no ambiente, pois aumenta as cargas de poluentes no meio e altera o ciclo hidrológico natural, criando riscos à população. É possível reduzir tais riscos através do diagnóstico, planejamento e gestão adequada das áreas de risco para a proteção civil e das comunidades. A abordagem ecohidrológica, que considera a relação funcional entre hidrologia, sistemas aquáticos e sua biota na escala de bacia hidrográfica, incorporando aspectos quantitativos e qualitativos da água em uma visão de interdependência entre Ecologia e Hidrologia, permite o diagnóstico, planejamento e manejo adequado dos cursos hídricos em benefício tanto dos humanos quando dos demais seres vivos. Este trabalho busca investigar a dinâmica ecohidrológica no espaço e no tempo da Bacia do Rio Monjolinho, localizada no Município de São Carlos (SP), no contexto de gestão de riscos de desastres hidrológicos. Os processos quantitativos são investigados por meio de simulações com o SWMM (Storm Water Management Model) e os dados de simulação são utilizados, por vez, na determinação do IP (Índice de Perigo) de pontos estratégicos da bacia hidrográfica e também das áreas com maior risco de inundação. Com relação à qualidade, onze variáveis clássicas de qualidade dágua são determinadas experimentalmente em 15 pontos da bacia a fim de caracterizar a dinâmica das cargas de poluentes, permitindo desta maneira a avaliação do risco biológico na bacia. Os resultados quali-quantitativos mostram que os vales dos rios oferecem riscos tanto devido às inundações quanto devido ao alto risco de contaminação. / The urban tissue expansion and the urban area densification have a negative impact on water resources, in terms of quality and quantity of available water, since it increases the polutant load at the same time it changes the natural hydrological cycle, exposing population to risk. It is possible to reduce the risks by means of assessment, planning and correct management of risk areas in order to protect the communities. The ecohydrology, which takes into account the functional relationship between hydrology, aquatic systems and biota in watershed scale, considering quali-quantitative aspects and their interdependecies, enable us to assess, plan and manage risks in an advantageous way for humans and living beings as well. This work investigates the ecohydrology dynamics in space and time of Rio Monjolinho basin, located within the municipality of São Carlos (SP), Brazil, in the context of disaster risk management. The quantitative aspects are investigated using the SWMM (Storm Water Management Model) simulation model, and the simulation data generated are used to calculate the Risk Index (RI) and to map the flooding risk areas in the basin. Eleven classic water quality variables are experimentaly determined to assess the polutant load dynamics and its distribution in the sub-basins, enabling us to assess the biologic risks. The results show that some areas in the catchment are not just flood risk areas but also areas of high biological risk of contamination.
1052

Implementação de um sistema SIP para o sistema operacional Linux

Silva, Davison Gonzaga da 03 August 2018 (has links)
Orientador: Leonardo de Souza Mendes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-03T18:53:15Z (GMT). No. of bitstreams: 1 Silva_DavisonGonzagada_M.pdf: 885396 bytes, checksum: 09530eec1ff6b03c4cb01ae4e9f06123 (MD5) Previous issue date: 2003 / Mestrado
1053

Comparison of System Performance During DDoS Attacks in Modern Operating Systems

Pettersson, Erik January 2017 (has links)
Distributed Denial of Service attacks are an ever prevalent challenge for system administra-tors today to overcome. The attack, which is all about restricting legitimate users access to a service, such as a web-page. Can cost companies and governments millions of dollars if not properly managed. This study aims to explore if there is any difference in performance between some of the most modern iterations of popular server operating systems today. Those server operating systems are: Windows Server 2016, Ubuntu 16 and FreeBSD 11. And submitting them to one of the most popular DDoS attacks at the time of writing, a so called HTTP-Get request. The webservers used are some of the most widely used today, Apache and Microsoft IIS. Each server will be submitted to attacks, and compared between one another. Different de-fence methods will also be tested and examined. Tests include shorter tests that is repeated multiple times for data validity, and one longer test for every condition in order to control if the results are similar. During these tests, the operating systems will measure CPU/RAM utilization, and a control computer will measure Round Trip Time. Windows Server 2016 using IIS and FreeBSD 11 perform similarly resource wise, but Win-dows Server 2016 with IIS had a better Round Trip Time performance. Windows Server 2016 with Apache performs worst in all measurements, while Ubuntu 16 performs in the middle, but has the most stable performance.
1054

Integration of heterogeneous wireless access networks with IP multimedia subsystem

Peyman, Talebifard 05 1900 (has links)
Next generation heterogeneous wireless networks are expected to interwork with Internet Protocol (IP)-based infrastructures. Conventional network services operate like silos in that a specific set of services are offered over a specific type of access network. As access networks evolve to provide IP-based packet access, it becomes attractive to break these “service silos” by offering a converged set of IP-based services to users who may access these services using a number of alternative access networks. This trend has started with third generation cellular mobile networks, which have standardized on the use of the IP Multimedia Subsystem (IMS) to manage user access to a wide variety of multimedia services over the mobile Internet, while facilitating interworking of heterogeneous wireless and landline access networks. The future users of communication systems will subscribe to both IP-based and Circuit Switched (CS) based services and in the foreseeable future a single database that handles user profiles across all domains will be required. Home Subscriber Server (HSS) as an evolved version of Home Location Register (HLR) is one of the key components of IMS. In deploying HSS as a central repository database, in a fully overlapped heterogeneous network setting, changes of access mode are very frequent and conveying this information to HSS imposes excessive signaling load and delay. In our proposed scheme we introduce an Interface Agent (IA) for each location area that caches the location and information about the access mode through which a user can be reached. This method results in significant amount of savings in signaling cost and better delay performance. The existing call delivery approaches in cellular networks may not be well suited for future communication systems because they suffer from unnecessary usage of network resources for call attempts that may fail which adds to excessive signaling delays and queuing costs. Reducing the number of queries and retrievals from the database will have a significant impact on the network performance. We present a new scheme based on Reverse Virtual Call setup (RVC) as a solution to the call delivery problem in heterogeneous wireless networks and evaluate the performance of this framework. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate
1055

TCP performance in an EGPRS system

Adolfsson, Klas January 2003 (has links)
The most widely used protocol for providing reliable service and congestion control in the Internet is the Transmission Control Protocol (TCP). When the Internet is moving towards more use in mobile applications it is getting more important to know how TCP works for this purpose. One of the technologies used for mobile Internet is the Enhanced General Packet Radio Service (EGPRS) extension to the popular GSM system. This thesis presents a low-level analysis of TCP performance in an EGPRS system and an overview of existing TCP, GSM and EGPRS technologies. The bottleneck in an EGPRS system is the wireless link – the connection between the mobile phone and the GSM base station. The data transfer over the wireless link is mainly managed by the complex RLC/MAC protocol. In this thesis, simulations were made to identify some problems with running TCP and RLC/MAC together. The simulations were made using existing EGPRS testing software together with a new TCP module. The simulation software is also briefly described in the thesis. Additionaly, some suggestions are given in order to enhance performance, both by changing the EGPRS system and by modifying the TCP algorithms and parameters.
1056

Analysis and implementation of a call simulator for Mobile@Home at Ericsson AB / Analys och implementering av en samtalssimulator för Mobile@Home, Ericsson AB

Larsson, Rasmus, Wikström, Edvard January 2004 (has links)
Mobile telephony technology like GSM made portable telephony a possibility. The arising and development of the Internet made a revolutionary change to communication and interchange of information. Bluetooth wireless technology revolutionizes personal connectivity by providing freedom from wired connections. Combining these technologies together brings the concept of Mobile@Home of Ericsson. Mobile@Home is a fixed-mobile convergence concept using the fixed network to carry present and future mobile services (e.g. voice, video, mail and Internet access) all the way to the home or office. By combining the high bandwidth of the fixed access network with the wireless technology of Bluetooth, Mobile@Home makes it possible to deliver high bandwidth to the mobile phone. Mobile@Home requires a Bluetooth enabled mobile phone and a Bluetooth enabled HBS (Home Base Station), placed at the home or office. By means of fast IP access (ADSL, cable modem etc.) the HBS connects into the standard mobile core network through a HBSC (Home Base Station Controller). The purpose of this thesis is the generation of simulated traffic between the HBS and HBSC and to analyze its behavior. This primary involves generation of signaling through an internal protocol, provided by Ericsson, for management and call control, and generation of GSM EFR (Enhanced Full Rate) voice streams over the RTP (Real Time Protocol) protocol. The simulation will consist of both the HBS and MS (Mobile Station). A set of HBS: s with attached MS will call one another through the HBSC. In this assignment only the GSM signaling will be considered because of time and scope limitations. The goal is to validate the RTP traffic generated towards the HBSC. Parameters like packet loss, packet delay and erroneous packets will be analyzed.
1057

Utveckling av ett öppet Home Automation-protokoll för användning över IP-nätverk / Development of an open Home Automation protocol for use over IP networks

Johnsson, Kim, Turfors, Christoffer, Ericson, Eric January 2010 (has links)
Detta arbete tar upp utvecklingen av ett nytt protokoll för användning inom Home Automation över IP-nätverk, med stor vikt på flexibilitet och enkelhet. Vi valde att utveckla ett nytt protokoll för Home Automation då en granskning av dagens protokoll visar att dessa inte är tillräckligt öppna eller flexibla för att passa alla enheter som används eller alla scenarion som kan uppstå. I våra litteraturstudier samlades information in som skapade grunderna för vårt protokoll och gav oss en större inblick i teknikerna bakom dagens tekniker inom home automation. Detta gav oss även möjlighet att senare jämföra vårt färdiga protokoll med redan existerande protokoll för att se om vi lyckats skapa något som kan användas. Metoden vi valde för att utveckla protokollet är en generell designmetod där vi efter granskningen av tidigare protokoll tar fram ett antal punkter som det nya protokollet skall uppnå. Det visade sig dock vara problematiskt att få fram svar om vissa protokoll så vi frångick metoden genom att istället utveckla protokollet utefter ett antal olika scenarion som det bör kunna hantera. Resultatet av arbetet är ett protokoll som uppfyllde nästan alla mål vi satt upp för det. I de fall vi inte lyckades med att uppfylla målen har vi möjliggjort för framtida expanderingar. / This report covers the development of a new protocol for use in Home Automation over IP networks, with focus on flexibility and simplicity. We chose to develop a new protocol for Home Automation because a review of current protocols suggests that these aren't open or flexible enough to suit every device in use or every scenario that might be applicable. In our literature studies we gathered information for use as the basis of our protocol and give us more insight into the technologies behind current home automation protocols. This also gave us the opportunity to compare our finished protocol with existing protocols. The method we chose for developing the protocol is a generic design method where after reviewing existing protocols, we establish a number of goals for the new protocol. It did however turn out to be difficult to acquire relevant information about some of the protocols. Because of this we used a slightly different approach, basing the new protocol on a number of scenarios we want it to be able to handle. The result is a protocol which satisfied almost every goal we established. For the few it didn't, we made it possible to satisfy them with future expansions.
1058

The Role of Intellectual Property in (Precompetitive) Public-Private Partnerships in the Biomedical Sector

Stevens, Hilde 15 June 2015 (has links)
info:eu-repo/semantics/nonPublished
1059

A high-level methodology for automatically generating dynamically reconfigurable systems using IP-XACT and the UML MARTE profile / Méthodologie de conception de haut niveau pour la génération automatique des systèmes dynamiquement reconfigurables en utilisant IP-XACT et le profil UML MARTE

Ochoa Ruiz, Gilberto 14 November 2013 (has links)
La principale contribution de cette thèse porte sur la proposition et le développement d'une approche d'Ingénierie Dirigée par les Modèles (IDM), liée à une méthodologie basée sur des composants, pour faciliter la conception, design et implantation des Systèmes Dynamiquement Reconfigurables sur puce (FPGA). La méthodologie proposée repose sur l'utilisation du paradigme Metadata-based Composition Framework, et fortement basée sur des standards, tels qu'UML MARTE et, en particulier, l'IEEE IP-XACT, qui est exploitée comme représentation intermédiaire pour les IPs utilisés et pour la plateforme matérielle composée aux hautes-niveaux d'abstraction. Un procès d'emballage permet la réutilisation des bloques IP, qui ont été enveloppés par des interfaces PLB (IP statiques) et propriétaires (IP dynamiques). Subséquemment, la libraire est utilisée pour la composition d'un modèle de plateforme en UML, mais qui étant générative, permet la création d'une description cible de la composante matérielle de la plateforme, dans la forme d'un modèle spécifique à Xilinx Platform Studio, obtenu par des transformations des modèles. Les chaines de transformations pour la création de la libraire et de la plateforme, respectivement, ont été développées et implantées en utilisant Sodius MDWorkbench, un outil IDM conçu pour la création et manipulation des modèles et leur méta - modèles, ainsi que la définition et exécution des transformations des modèles associées / The main contribution of this thesis consists on the proposition and development a Model-driven Engineering (MDE) framework, in tandem with a component-based approach, for facilitating the design and implementation of Dynamic Partially Reconfigurable (DPR) Systems-on-Chip. The proposed methodology has been constructed around the Metadata-based Composition Framework paradigm, and based on common standards such as UML MARTE and the IEEE IP-XACT standard, an XML representation used for storing metadata about the IPs to be reused and of the platforms to be obtained at high-levels of abstraction. In fact, a componentizing process enables us to reuse the IP blocks, in UML MARTE, by wrapping them with PLB (static IPs) and proprietary (DPR blocks) interfaces. This is attained by reflecting the associated IP metadata to IP-XACT descriptions, and then to UML MARTE templates (IP reuse). Subsequently, these IP templates are used for composing a DPR model that can be exploited to create a Xilinx Platform Studio FPGA-design, through model transformations. The IP reflection and system generation chains were developed using Sodius MDWorkbench, an MDE tool conceived for the creation and manipulation of models and their meta-models, as well as the definition and execution of the associated transformation rules.
1060

Identification Of Novel MLH 1p Interacting Proteins By Biochemical And Genetic Methods

Kumaran, M 01 1900 (has links) (PDF)
No description available.

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