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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.
371

Um middleware reconfigurável para redes de sensores sem fio

Souza Vieria, Mardoqueu January 2006 (has links)
Made available in DSpace on 2014-06-12T15:59:39Z (GMT). No. of bitstreams: 2 arquivo5463_1.pdf: 1462415 bytes, checksum: 975980491ca4b4412b374f07a3f2612d (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2006 / A atratividade das Redes de Sensores Sem Fio (RSSF) para o monitoramento das condições do ambiente e para servir de ponte entre o mundo físico e o virtual vem aumentando devido aos avanços da micro-eletrônica, que possibilitaram a produção de vários tipos de sensores (luz, umidade, temperatura, fumaça, radiação, acústicos, sísmicos, etc.) no mesmo chip que processa o sinal e realiza a comunicação. As RSSF podem ser consideradas ambientes de computação distribuída com severas restrições de velocidade de processamento, tamanho de memória, energia e largura de banda. Individualmente os nós das redes de sensores são tipicamente não confiáveis e a topologia da rede pode mudar dinamicamente. As redes de sensores também se diferenciam por causa da estreita interação com o ambiente físico através de sensores e atuadores. Devido à todas estas diferenças, muitas soluções desenvolvidas para plataformas de computação genéricas e para redes ad-hoc não podem ser aplicadas às RSSF. Todavia, os nós das redes de sensores também exibem características de sistema de propósito geral e de sistemas embutidos. Os sistemas de middleware para RSSF têm objetivos similares (ex., comunicação) aos dos sistemas de middleware tradicionais como CORBA, RMI, JINI, DCOM e PVM, porém têm restrições diferentes. Os sistemas de middleware tradicionais geralmente consomem demasiadamente recursos como processamento, memória e largura de banda, enquanto que nas RSSF estes recursos são escassos dificultando a tarefa de desenvolver sistemas de middleware para estas redes. O desenvolvimento de middleware para RSSF é o tema central desta dissertação. O middleware desenvolvido nesta dissertação deve possui as seguintes características: adaptação do comportamento da aplicação devido à disponibilidade de recursos e características do ambiente físico; comunicação entre nós da rede permitindo também a comunicação assíncrona, pois é mais adequada ao modelo de disseminação de informação requerido por aplicações em RSSF; combinação ou fusão de dados provenientes de fontes diferentes eliminando redundância, minimizando o número de transmissões e assim economizando energia; e gerenciamento de grupos de nós para dar suporte à aplicações de rastreamento de objetos, tolerância a falhas, segurança, sincronização de relógios e gerenciamento de energia. Para realizar as características mencionadas, apresentamos o projeto, a implementação e a validação de um middleware para RSSF. Este middleware é visto como uma coleção de serviços (de middleware) fornecidos através de uma API (Application Programming Interface) e é composto pelos serviços de: comunicação, que provê canais de comunicação broadcast e publish-subscribe; reconfiguração, responsável pela reconfiguração de componentes da aplicação e serviços do middleware; gerenciamento de grupos, que provê um modelo de gerenciamento de grupos de nós da rede; e de agregação, que realiza a combinação de dados para diminuir o envio de dados pela rede
372

Êxodo Framework: uma solução para modelagem do comportamento de ambientes para Internet das Coisas / Êxodo Framework: a solution for behavior modeling for Internet of Things Enviroment

Teles Júnior, Namedin Pereira, 92981237980 26 February 2018 (has links)
Submitted by Namedin Teles Júnior (namedinteles@gmail.com) on 2018-11-26T19:12:07Z No. of bitstreams: 1 NAMEDIN-TESE-FINALIZADA.PDF: 9240706 bytes, checksum: 78feca64ce0f19f7657801377599ff22 (MD5) / Approved for entry into archive by Secretaria PPGI (secretariappgi@icomp.ufam.edu.br) on 2018-11-26T19:20:31Z (GMT) No. of bitstreams: 1 NAMEDIN-TESE-FINALIZADA.PDF: 9240706 bytes, checksum: 78feca64ce0f19f7657801377599ff22 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-11-26T19:40:39Z (GMT) No. of bitstreams: 1 NAMEDIN-TESE-FINALIZADA.PDF: 9240706 bytes, checksum: 78feca64ce0f19f7657801377599ff22 (MD5) / Made available in DSpace on 2018-11-26T19:40:39Z (GMT). No. of bitstreams: 1 NAMEDIN-TESE-FINALIZADA.PDF: 9240706 bytes, checksum: 78feca64ce0f19f7657801377599ff22 (MD5) Previous issue date: 2018-02-26 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / The Internet of Things or IoT is a paradigm of computing in which devices and objects of the physical world (e.g. televisions, refrigerators and conditioners air) are connected through the Internet, providing services and exchanging information between in a global scale. This new paradigm has led the market to present solutions that increasingly bring IoT closer to everyday life. Manufacturers such as Samsung, Philips, GE and Belkin already have hardware solutions (e.g. smartphones, smart TV, smart plugs and sensors) that allow users to interact with the environment, and can turn on, off and even view statistical data on power consumption these devices. However, the main platforms that allow IoT to be enabled are still little used due to their complexity, being restricted only to expert users, that is, users who have technical knowledge in IoT, not allowing non- expert users to adapt these solutions and create environments for IoT according to your needs. In this context, this work presents the Exodus framework, a new approach to IoT with a focus on expert user and non-expert user. Exodus is a solution for IoT that can be extended and adapted to meet the different needs of the environment such as the inclusion of new devices and services and / or the definition of new behaviors to the environment. In order to define the different behavior that the environment can take, the Exodus has a graphical solution that makes use of a conceptual model called BDM4IoT (Behavior Definition Model for Internet of Things Ecosystems) that together allow the users to model the behavior of the environment according to With their needs, allowing them to create from simple models such as a home lighting scheme to more complex models such as the behavior of a production line in an industrial environment. The results obtained with experiments carried out with the BDM4IoT model and with the graphical tool, demonstrate the efficiency of this approach, allowing the inclusion of non-expert users in processes previously performed only by IoT specialists. / Internet das Coisas ou IoT (do Inglês, Internet of Things) é um paradigma da computação no qual dispositivos e objetos do mundo físico (e.g. televisões, geladeiras e condicionadores de ar) estão conectados por meio da Internet, provendo serviços e trocando informações entre si em uma escala global. Esse novo paradigma tem levado o mercado a apresentar soluções que cada vez mais aproxima a IoT do cotidiano das pessoas. Fabricantes como Samsung, Philips, GE e Belkin já dispõem de soluções de hardware (e.g. smartphones, smart TV, smart plugs e sensores) que permitem que os usuários interajam com ambiente, podendo ligar, desligar e até mesmo visualizar dados estatísticos do consumo de energia desses dispositivos. No entanto, as principais plataformas que permitem habilitar a IoT ainda são pouco utilizadas devido à sua complexidade, sendo restritas apenas a usuários especialistas, ou seja, a usuários que possuem conhecimento técnico em IoT. Além disso, as atuais ferramentas não permitem que usuários não especialistas possam adaptar essas soluções e criar ambientes para IoT de acordo com as suas necessidades. Nesse contexto, esse trabalho apresenta o framework Êxodo, uma nova abordagem para IoT com foco em usuário especialista e no usuário não especialista. O Êxodo é uma solução para IoT que pode ser estendida e adaptada para atender as diferentes necessidades do ambiente como a inclusão de novos dispositivo e serviços e/ou a definição de novos comportamentos ao ambiente. Para a definição dos diferentes comportamento que o ambiente poderá assumir, o Êxodo possui uma solução gráfica que faz uso de um modelo conceitual denominado BDM4IoT (Behavior Definition Model for Internet of Things Ecosystems) que possibilita que os usuários modelem o comportamento do ambiente de acordo com as suas necessidades, permitindo que esses possam criar desde modelos simples, como um esquema de iluminação de uma casa, a modelos mais complexos, como o comportamento de uma linha de produção de um ambiente industrial. Os resultados obtidos com experimentos realizados com o framework Êxodo demonstram a eficiência dessa abordagem, possibilitando a inclusão de usuários não especialistas em processos antes realizados somente por usuários especialistas em IoT.
373

Performance Evaluation of Windows Communication Foundation’s Interoperability

Hamayun, Muhammad, Ahmed, Nadeem January 2010 (has links)
Middleware eases the development of distributed applications. Expansion in the enterprise world entails integration of heterogeneous products, and there is a demand for a balance between performance, interoperability and security in the distributed applications. Windows Communication Foundation (WCF) offers a technology to build service-oriented, secure, reliable and interoperable distributed applications. The current literature contains few studies comparing the performance of WCF with other technologies, but it does not address the performance of WCF in a cross-technology communication. This master thesis experimentally evaluates the performance of WCF in unsecure and secure variants. It evaluates the performance in on-machine and cross-machine communication, and it addresses the performance of WCF’s interoperability with ASMX and Java. We have developed the service and client applications in both secure and unsecure variants. The experiments are then conducted using these applications in a laboratory setting. We have measured the performance in terms of throughput, response time, processor and memory utilization during the experiments. Our results show that in unsecure variants, the WCF service in cross-machine communication has the best response time than on-machine communication on small datasets. However, on large datasets the service in on-machine communication has the best response time. In secure variants, the service in on-machine communication has better response time than the cross-machine communication. In both secure and unsecure variants, the service has better throughput and consumed lesser resources in cross-machine communication than in on-machine communication. In case of WCF’s interoperability with ASMX and Java, both the secure as well as unsecure WCF service show more scalable performance for the WCF client than for ASMX and Java clients. The secure as well as unsecure service show better performance for the ASMX client than for the Java client. The unsecure variants of WCF service perform better than the secure variants, except in a few cases of memory utilization. Therefore, the performance of the WCF service degrades due to security.
374

Performance Analysis of Distributed Object Middleware Technologies / Prestanda Analys av Distribuerade Objektorienterade Mellanlager

Arneng, Per, Bladh, Richard January 2003 (has links)
Each day new computers around the world connects to the Internet or some network. The increasing number of people and computers on the Internet has lead to a demand for more services in different domains that can be accessed from many locations in the network. When the computers communicate they use different kinds of protocols to be able to deliver a service. One of these protocol families are remote procedure calls between computers. Remote procedure calls has been around for quite some time but it is with the Internet that its usage has increased a lot and especially in its object oriented form which comes from the fact that object oriented programming has become a popular choice amongst programmers. When a programmer has to choose a distributed object middleware there is a lot to take into consideration and one of those things is performance. This master thesis aims to give a performance comparison between different distributed object middleware technologies and give an overview of the performance difference between them and make it easier for a programmer to choose one of the technologies when performance is an important factor. In this thesis we have evaluated the performance of CORBA, DCOM, RMI, RMI-IIOP, Remoting-TCP and Remoting-HTTP. The results we have seen from this evaluation is that DCOM and RMI are the distributed object middleware technologies with the best overall performance in terms of throughput and round trip time. Remoting-TCP generally generates the least amount of network traffic, while Remoting-HTTP generates the most amount of network traffic due to it's SOAP-formated protocol. / Detta magister arbete handlar om en prestanda analys av distribuerade objectorienterande mellanlagers teknologier. Dokumentet jämför prestandan på följande teknologier: CORBA, DCOM, RMI, RMI-IIOP, Remoting-TCP and Remoting-HTTP. Jämförelsen är i både server och klient perspektiv. / The authors can probably not be reached on the e-mail addresses given here or in the thesis. A simple search on any search engine will probably lead to valid an address. The reason for this is becouse the student mail is not a longterm address.
375

A SmartWardrobe : Augmenting laundry planning

Mumala, Wenceslaus, Oke, Vincent January 2007 (has links)
Trends in technologies have mostly focused on the work environment, entertainment and communication technologies. Some developments have been made for the home such as microwave ovens, washing machines, HDTV, etc but most tasks are still manually executed. Washing machines are used in laundry but there hasn’t been a significant saving in time compared to manual laundering. The effects of misuse of the machine can be very destructive to clothes. This calls for proper sorting of clothes and adjustment of washing settings as appropriate. However, sorting has become a time consuming activity that requires a lot of attention on the part of the individual. Due to fatigue, individuals may in turn not pay much attention to washing instructions. In this thesis, we put together technologies into a system that would aid the user in planning and executing a laundry through identification of dirty clothes and sorting them in groups that can go into separate washes.
376

Distributed Electronic Health Record System based on Middleware

Xin, Zhang January 2013 (has links)
With the fast development of information technology, traditional healthcare is evolving to a more digital and electronic stage. Electronic HealthRecord (EHR) is residents’ basic information and health care relatedinformation conforming to standard. It can not only provide usefulinformation to medical workers, but also exchange resources with otherinformation systems. But with the growing complexity of electronichealth record data sources, it becomes a big challenge to set up a structurewhich allows different types of data sharing and exchanging inmulti-platform applications. It’s even more important to find out amethod to support great amount of users from different applicationplatform to sharing and exchanging data at the same time.In this paper, we proposed a distributed electronic health record systembased on middleware to address the problem. Both permanent and realtimedata should pass through the middleware provided by the system,and will be transformed into standard format for storage. Multi-threadand distributed server group design will let the system be more flexibleand scalable, and will be able to provide service to users concurrently.The system creates a standard data format for data transferring andstorage. All raw data collected from different kinds of sensor system willbe formatted with application programming interface (API) or softwaredevelopment kit (SDK) system provided before upload to the system.Encryption methods are also implemented to ensure data security andprivacy protection.
377

Middleware med Google Web Toolkit

Öberg, Viktor January 2012 (has links)
Detta examensarbete har utförts i samarbete med företaget Systemagic AB. Systemagic är ett teknikföretag vars expertis ligger inom mjukvaruutveckling inom IPTV-teknologi. Detta innefattar bland annat utveckling av middleware till digitalboxar, också kallade Set-top-boxar. Middleware är den mjuk- och hårdvaruinfrastruktur som sammankopplar de olika delarna av ett IPTV-system. Det är ett distribuerat operativt system som både finns på operatörens servrar samt i slutanvändarens digitalbox. Då det idag ställs allt högre krav på funktionalitet och dynamik från beställare blir utvecklingen av ett modernt middleware mycket resurskrävande. Systemagic anser att en stor bidragande orsak till den resurskrävande utvecklingsprocessen kan kopplas till användningen av scriptspråket JavaScript och är därför intresserade av alternativa metoder. Google Web Toolkit (GWT) är ett Java-ramverk som kan användas för att på ett snabbt och smidigt sätt utveckla interaktiva webbapplikationer. Detta möjliggörs genom att all utveckling sker i Java. Slutprodukten efter kompilering är standard-kompatibel HTML och JavaScript, helt oberoende av Java. Detta examensarbete har gått ut på att undersöka möjligheten att använda Java och GWT för att underlätta och potentiellt snabba upp utvecklingen av ett middleware. Målet var att undersöka om GWT kan användas rakt av för att ta fram den del av ett middleware som återfinns i slutanvändarens box, en så kallad portal, eller om ramverket måste anpassas för att de mest grundläggande funktionerna hos en box ska kunna implementeras. Rapporten beskriver frågeställningar, tillvägagångssätt, problem och  svårigheter som uppstod, de lösningar som använts samt en analys och diskussion av resultatet.
378

CORBA and Web Service Performance Comparison for Reliable and Confidential Message Transmission in Heterogeneous Distributed Systems

Miess, Jürgen January 2004 (has links)
The business pressures which companies and organisations encounter are steadily growing. They continuously have to improve their efficiency to keep up with these new developments. One very important aspect in doing so is the reinforced adoption of computer based information systems. This paper focuses on a computer based system which is able to automate everyday business communication between distributed team members. Reliable and confidential message delivery, event notification, the integration of different end devices (mobile phones, PCs etc.) and the message transport across different networks (wireless, wired) have been allocated as the main system requirements. Based on these requirements the performance of two middleware technologies, namely CORBA and Web services, has been compared. The result of this comparison was that both technologies are suited to use for implementing such a system but both too, have strengths and weaknesses in achieving the stated requirements. CORBA for example, due to several supporting, already included services, allows the programmer to concentrate on the application development itself and use these services to ensure reliable and confidential message transmission. Additionally, CORBA is very efficient in using the bandwidth of the underlying communication network, but makes higher demands to the memory space available on clients. This is critical, if clients are mobile devices with limited resources. Web service technology is much more modest than CORBA with respect to the client side memory space, but message transmission requires much more bandwidth. Further one there are no built-in security and reliability services available for Web services, like there are for CORBA. Hence it is up the application programmer to manually implement these features; however he has not necessarily develop everything from scratch but can resort to already existing specifications, still having the freedom of developing specially tailored features. In short could be stated that CORBA is more consequential and consistent and WS technology is more adjustable and flexible.
379

Integration of user generated content with an IPTV middleware

Leufvén, Johan January 2009 (has links)
IPTV is a growing form of distribution for TV and media. Reports show that the market will grow from the current 20-30 million subscribers to almost 100 million 2012. IPTV extends the traditional TV viewing with new services like renting movies from your TV. It could also be seen as a bridge between the traditional broadcast approach and the new on demand approach the users are used to from internet. Since there are many actors in the IPTV market that all deliver the same basic functionality, companies must deliver better products that separate them from the competitors. This can be done either through doing things better than the others and/or delivering functionality that others can’t deliver. This thesis project presents the development of a prototype system for serving user generated content in the IPTV middleware Dreamgallery. The developed prototype is a fully working system that includes (1) a fully automated system for transcoding, of video content. (2) A web portal presented with solutions for problems related to user content uploading and administration. (3) Seamless integration with the Dreamgallery middleware and end user GUI, with two different ways of viewing content. One way for easy exploration of new content and a second more structured way of browsing the content. A study of three open source encoding softwares is also presented. The three encoders were subjects to tests of: speed, agility (file format support) and how well they handle files with corrupted data.
380

Middleware Systems for Opportunistic Computing in Challenged Wireless Networks / Support des applications distribuées dans les réseaux mobiles ad hoc à continuité partielle

Benchi, Abdulkader 29 June 2015 (has links)
Les réseaux mobiles opportunistes (ou OppNets, pour Opportunistic Networks) constituent une solution séduisante pour compléter les réseaux fixes d’infrastructure, voire compenser leur absence dans des zones sinistrées ou défavorisées. Les recherches menées ces dernières années ont principalement visé à permettre les transmissions dans les OppNets, mais ceci ne peut être qu’un premier pas vers une réelle exploitation de tels environnements contraints. L’informatique opportuniste (Opportunistic Computing) dépasse le cadre des seules transmissions, et introduit un nouveau paradigme d’exécution de tâches collaboratives dans de tels environnements. Dans ce domaine qu’est l’informatique opportuniste, la conception, la mise en œuvre et le déploiement d’applications distribuées sont des objectifs majeurs. Une application pour OppNet doit pouvoir fonctionner et assurer un niveau de service satisfaisant, tout en supportant les diverses contraintes propres aux OppNets, telles qu’une connectivité fluctuante, un partitionnement chronique du réseau, de longs délais de transmissions, de fréquents échecs de transmission, et des équipements hétérogènes offrant des ressources limitées. La complexité et le coût du développement d’applications pour OppNets peuvent être réduits de manière significative en utilisant des modèles de programmation appropriés. De tels modèles peuvent être fournis par des systèmes intergiciels capables de supporter de manière transparente les contraintes évoquées plus haut. Le travail rapporté dans ce mémoire a porté sur l’étude des contraintes inhérentes aux OppNets, et sur la proposition de solutions appropriées. Parmi les modèles de programmation usuels, certains ont été identifiés comme pouvant être utilisés dans le cadre des OppNets. Sur la base de ces divers modèles de programmation, des systèmes intergiciels opportunistes ont été mis en oeuvre. Ces systèmes supportent respectivement le modèle de messagerie distribuée (sur la base de files d’attentes et de "topics"), le modèle du tuple-space, et la résolution de consensus. Des implémentations complètes ont été réalisées, et le code source est distribué sous licence GPL (GNU General Public License). Ces systèmes ont été évalués par le biais d’expérimentations menées en conditions réelles et par simulation. / Opportunistic networks (OppNets) constitute an appealing solution to complement fixed network infrastructures –or make up for the lack thereof– in challenged areas. Researches in the last few years have mostly addressed the problem of supporting networking in OppNets, yet this can only be a first step towards getting real benefit from these networks. Opportunistic computing goes beyond the concept of opportunistic networking, and provides a new paradigm to enable collaborative computing tasks in such environments. In the realm of opportunistic computing, properly designing, implementing and deploying distributed applications are important tasks. An OppNet-dedicated application must be able to operate and maintain an acceptable level of service while addressing the many problems that can occur in these networks, such as disconnections, partitioning, long transmission delays, transmission failures, resource constraints, frequent changes in topology, and heterogeneous devices. Much of the complexity and cost of building OppNet-dedicated applications can be alleviated by the use of high-level programming models. Such models can be supported by middleware systems capable of transparently addressing all the above-mentioned problems. The work reported in this dissertation focused on providing insight into the fundamental problems posed by OppNets, so as to analyze and solve the problems faced by application developers while dealing with these environments. The research focused on identifying well-known high-level programming models that can be satisfactorily implemented for OppNets, and that can prove useful for application developers. In order to demonstrate the feasibility of application development for OppNets, while assessing the benefits brought about by carefully designed middleware systems, a couple of such systems have been designed, implemented, and evaluated as part of this work. These middleware systems respectively support distributed messaging (through message queues and topics), the tuple-space model, and consensus solving in OppNets. They are supplemented with fully-functional implementations, that can be used in real settings, and that are all distributed under the terms of the GNU General Public License (GPL). Real-life experiments and simulations have been realized so as to evaluate the effectiveness and efficiency of these systems in real conditions.

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