Spelling suggestions: "subject:"8ecision algorithm"" "subject:"becision algorithm""
1 |
SCALABLE AND EFFICIENT VERTICAL HANDOVER DECISION ALGORITHMS IN VEHICULAR NETWORK CONTEXTSMárquez Barja, Johann Marcelo 23 November 2012 (has links)
A finales de los años noventa, y al comienzo del nuevo milenio, las redes inalámbricas han evolucionado bastante, pasando de ser sólo una tecnología prometedora para convertirse en un requisito para las actividades cotidianas en las sociedades desarrolladas. La infraestructura de transporte también ha evolucionado, ofreciendo comunicación a bordo para mejorar la seguridad vial y el acceso a contenidos de información y entretenimiento.
Los requisitos de los usuarios finales se han hecho dependientes de la tecnología, lo que significa que sus necesidades de conectividad han aumentado debido a los diversos requisitos de las aplicaciones que se ejecutan en sus dispositivos móviles, tales como tabletas, teléfonos inteligentes, ordenadores portátiles o incluso ordenadores de abordo (On-Board Units (OBUs)) dentro de los vehículos. Para cumplir con dichos requisitos de conectividad, y teniendo en cuenta las diferentes redes inalámbricas disponibles, es necesario adoptar técnicas de Vertical Handover (VHO) para cambiar de red de forma transparente y sin necesidad de intervención del usuario.
El objetivo de esta tesis es desarrollar algoritmos de decisión (Vertical Handover Decision Algorithms (VHDAs)) eficientes y escalables, optimizados para el contexto de las redes vehiculares. En ese sentido se ha propuesto, desarrollado y probado diferentes algoritmos de decisión basados en la infraestructura disponible en las actuales, y probablemente en las futuras, redes inalámbricas y redes vehiculares. Para ello se han combinado diferentes técnicas, métodos computacionales y modelos matemáticos, con el fin de garantizar una conectividad apropiada, y realizando el handover hacia las redes más adecuadas de manera a cumplir tanto con los requisitos de los usuarios como los requisitos de las aplicaciones.
Con el fin de evaluar el contexto, se han utilizado diferentes herramientas para obtener información variada, como la disponibilidad de la red, el estado de la red, la geolocalización / Márquez Barja, JM. (2012). SCALABLE AND EFFICIENT VERTICAL HANDOVER DECISION ALGORITHMS IN VEHICULAR NETWORK CONTEXTS [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/17869 / Palancia
|
2 |
Um algoritmo de decisão de Handover baseado em QoS e autonomia energéticaSilva, Sávio Roberto Amorim Aragão 27 May 2015 (has links)
A key step in the handover process corresponds to the decision phase in which the mobile device selects the candidate network that it will be attached to. The criterion generally used
in the decision step is the signal strength of the available network. In addition to the signal power, other criteria also need to be explored in heterogeneous environments for taking
handover decision, since the network technologies differ in the types of services, protocols, quality standards, frequency bands and monetary costs. This paper proposes a handover
decision algorithm based on cost function that takes into account both the received signal power, some quality of service criteria such as packet loss rate, delay and jitter, as well as
the energy consumption of network interface of the mobile station. In order to evaluate the performance of the algorithm were considered two scenarios, one in which the battery of
device mobile is sufficiently charged and another where it meets the low load. Simulations in NS-2 were performed in an environment compound by the Wi-Fi and WiMAX networks.
The results showed that the proposed algorithm helped to reduce the number of wrong handovers decisions, so that there was no deterioration in the quality of service that would affect
the performance of the network in which the mobile device is currently connected. / Uma etapa fundamental no processo de handover corresponde à fase de decisão, na qual é selecionada a rede candidata para a qual o dispositivo móvel irá se transferir. O critério
normalmente utilizado na etapa de decisão é a potência de sinal da rede que se encontra disponível. Além da potência de sinal, outros critérios também necessitam ser explorados em
ambientes heterogêneos para a tomada de decisão de handover, uma vez que as tecnologias de rede divergem quanto aos tipos de serviços, protocolos, níveis de qualidade, faixas de
frequência e custos monetários. Este trabalho propõe um algoritmo de decisão de handover baseado em função de custo que leva em consideração, além da potência de sinal recebida,
alguns critérios de Qualidade de Serviço, tais como taxa de perda de pacotes, atraso e jitter, bem como o consumo de energia da interface de rede da estação móvel. A fim de avaliar o
desempenho do algoritmo foram considerados dois cenários, um no qual a bateria do terminal móvel está com carga suficiente e outro onde a mesma se encontra com a carga baixa, sendo
realizadas simulações no NS-2 em um ambiente composto pelas redes Wi-Fi e WiMAX. Os resultados obtidos mostraram que o algoritmo proposto contribuiu para reduzir o número de
decisões erradas de handovers, de modo que não houvesse uma degradação da Qualidade de Serviço que viesse a afetar o desempenho da rede na qual o terminal móvel se encontra
conectado.
|
3 |
An intelligent vertical handoff decision algorithm in next generation wireless networksNkansah-Gyekye, Yaw January 2010 (has links)
<p>The objective of the thesis research is to design such vertical handoff decision algorithms in order for mobile field workers and other mobile users equipped with contemporary multimode mobile devices to communicate seamlessly in the NGWN. In order to tackle this research objective, we used fuzzy logic and fuzzy inference systems to design a suitable handoff initiation algorithm that can handle imprecision and uncertainties in data and process multiple vertical handoff initiation parameters (criteria) / used the fuzzy multiple attributes decision making method and context awareness to design a suitable access network selection function that can handle a tradeoff among many handoff metrics including quality of service requirements (such as network conditions and system performance), mobile terminal conditions, power requirements, application types, user preferences, and a price model / used genetic algorithms and simulated annealing to optimise the access network selection function in order to dynamically select the optimal available access network for handoff / and we focused in particular on an interesting use case: vertical handoff decision between mobile WiMAX and UMTS access networks. The implementation of our handoff decision algorithm will provide a network selection mechanism to help mobile users select the best wireless access network among all available wireless access networks, that is, one that provides always best connected services to users.</p>
|
4 |
An intelligent vertical handoff decision algorithm in next generation wireless networksNkansah-Gyekye, Yaw January 2010 (has links)
<p>The objective of the thesis research is to design such vertical handoff decision algorithms in order for mobile field workers and other mobile users equipped with contemporary multimode mobile devices to communicate seamlessly in the NGWN. In order to tackle this research objective, we used fuzzy logic and fuzzy inference systems to design a suitable handoff initiation algorithm that can handle imprecision and uncertainties in data and process multiple vertical handoff initiation parameters (criteria) / used the fuzzy multiple attributes decision making method and context awareness to design a suitable access network selection function that can handle a tradeoff among many handoff metrics including quality of service requirements (such as network conditions and system performance), mobile terminal conditions, power requirements, application types, user preferences, and a price model / used genetic algorithms and simulated annealing to optimise the access network selection function in order to dynamically select the optimal available access network for handoff / and we focused in particular on an interesting use case: vertical handoff decision between mobile WiMAX and UMTS access networks. The implementation of our handoff decision algorithm will provide a network selection mechanism to help mobile users select the best wireless access network among all available wireless access networks, that is, one that provides always best connected services to users.</p>
|
5 |
An intelligent vertical handoff decision algorithm in next generation wireless networksNkansah-Gyekye, Yaw January 2010 (has links)
Philosophiae Doctor - PhD / The objective of the thesis research is to design such vertical handoff decision algorithms in order for mobile field workers and other mobile users equipped with contemporary multimode mobile devices to communicate seamlessly in the NGWN. In order to tackle this research objective, we used fuzzy logic and fuzzy inference systems to design a suitable handoff initiation algorithm that can handle imprecision and uncertainties in data and process multiple vertical handoff initiation parameters (criteria); used the fuzzy multiple attributes decision making method and context awareness to design a suitable access network selection function that can handle a tradeoff among many handoff metrics including quality of service requirements (such as network conditions and system performance), mobile terminal conditions, power requirements, application types, user preferences, and a price model; used genetic algorithms and simulated annealing to optimise the access network selection function in order to dynamically select the optimal available access network for handoff; and we focused in particular on an interesting use case: vertical handoff decision between mobile WiMAX and UMTS access networks. The implementation of our handoff decision algorithm will provide a network selection mechanism to help mobile users select the best wireless access network among all available wireless access networks, that is, one that provides always best connected services to users. / South Africa
|
6 |
An intelligent vertical handoff decision algorithm in next generation wireless networksGyekye, Yaw Nkansah January 2010 (has links)
Philosophiae Doctor - PhD / Seamless mobility is the missing ingredient needed to address the inefficient
communication problems faced by the field workforces of service companies that are using field workforce automation solutions to streamline and optimise the operations of their field workforces in an increasingly competitive market place. The key enabling function for achieving seamless mobility and seamless service continuity is seamless handoffs across heterogeneous wireless access networks. A challenging issue in the multi-service next generation wireless network (NGWN) is to design intelligent and optimal vertical handoff decision algorithms, beyond traditional ones that are based on only signal strength, to determine when to perform a handoff and to provide optimal choice of access network technology among all available access networks for users equipped with multimode mobile terminals. The objective of the thesis research is to design such vertical handoff decision algorithms in order for mobile field workers and other mobile users equipped with contemporary multimode mobile devices to communicate seamlessly in the NGWN. In order to tackle this research objective, we used fuzzy logic and fuzzy inference systems to design a suitable handoff initiation algorithm that can handle imprecision and uncertainties in data and process multiple vertical handoff initiation parameters (criteria); used the fuzzy multiple attributes decision making method and context awareness to design a suitable access network selection function that can handle a tradeoff among many handoff metrics including quality of service requirements (such as network conditions and system performance),
mobile terminal conditions, power requirements, application types, user preferences, and a price model; used genetic algorithms and simulated annealing to optimise the access network selection function in order to dynamically select the optimal available access network for handoff; and we focused in particular on an interesting use case: vertical handoff decision between mobile WiMAX and UMTS access networks. The implementation of our handoff decision algorithm will provide a network selection mechanism to help mobile users select the best wireless access network among all available wireless access networks, that is, one that provides always best connected services to users
|
Page generated in 0.0478 seconds