843 resultados para Predictable routing


Relevância:

20.00% 20.00%

Publicador:

Resumo:

A mobile Ad Hoc network (MANET) is a collection of wireless mobile nodes that can dynamically configure a network without a fixed infrastructure or central administration. This makes it ideal for emergency and rescue scenarios, where sharing information is essential and should occur as soon as possible. This article discusses which of the routing strategies for mobile MANETs: proactive, reactive or hierarchical, has a better performance in such scenarios. By selecting a real urban area for the emergency and rescue scenario, we calculated the density of nodes and the mobility model needed for the validation study of AODV, DSDV and CBRP in the routing model. The NS2 simulator has been used for our study. We also show that the hierarchical routing strategies are better suited for this type of scenarios.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A multivariate analysis on flood variables is needed to design some hydraulic structures like dams, as the complexity of the routing process in a reservoir requires a representation of the full hydrograph. In this work, a bivariate copula model was used to obtain the bivariate joint distribution of flood peak and volume, in order to know the probability of occurrence of a given inflow hydrograph. However, the risk of dam overtopping is given by the maximum water elevation reached during the routing process, which depends on the hydrograph variables, the reservoir volume and the spillway crest length. Consequently, an additional bivariate return period, the so-called routed return period, was defined in terms of risk of dam overtopping based on this maximum water elevation obtained after routing the inflow hydrographs. The theoretical return periods, which give the probability of occurrence of a hydrograph prior to accounting for the reservoir routing, were compared with the routed return period, as in both cases hydrographs with the same probability will draw a curve in the peak-volume space. The procedure was applied to the case study of the Santillana reservoir in Spain. Different reservoir volumes and spillway lengths were considered to investigate the influence of the dam and reservoir characteristics on the results. The methodology improves the estimation of the Design Flood Hydrograph and can be applied to assess the risk of dam overtopping

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Conventional dual-rail precharge logic suffers from difficult implementations of dual-rail structure for obtaining strict compensation between the counterpart rails. As a light-weight and high-speed dual-rail style, balanced cell-based dual-rail logic (BCDL) uses synchronised compound gates with global precharge signal to provide high resistance against differential power or electromagnetic analyses. BCDL can be realised from generic field programmable gate array (FPGA) design flows with constraints. However, routings still exist as concerns because of the deficient flexibility on routing control, which unfavourably results in bias between complementary nets in security-sensitive parts. In this article, based on a routing repair technique, novel verifications towards routing effect are presented. An 8 bit simplified advanced encryption processing (AES)-co-processor is executed that is constructed on block random access memory (RAM)-based BCDL in Xilinx Virtex-5 FPGAs. Since imbalanced routing are major defects in BCDL, the authors can rule out other influences and fairly quantify the security variants. A series of asymptotic correlation electromagnetic (EM) analyses are launched towards a group of circuits with consecutive routing schemes to be able to verify routing impact on side channel analyses. After repairing the non-identical routings, Mutual information analyses are executed to further validate the concrete security increase obtained from identical routing pairs in BCDL.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Hoy en día, los sistemas middleware de publicar-suscribir con la filtración de mensajes basado en contenido tiende a ser popularizado, y un sistema como este requiere codificar su mensaje a la combinación de varios elementos que se encuentran en los conjuntos no-interseccionados. Varios predicados posibles en los dominios de esos conjuntos forman un filtro, y el núcleo de algoritmo filtrado es seleccionar filtros adaptados tan pronto como sea posible. Sin embargo, el conjunto, que está formado por los filtros, contiene la extremadamente fuerte indeterminación y distensibilidad, lo que restringe el algoritmo filtrado. Por la resolución de la distensibilidad, se estudió la característica del conjunto de filtros en álgebra, y sabía que es un retículo específico. Por lo tanto, se intenta usar el carácter, el cual los retículos forman un conjunto parcialmente ordenado (o poset, del inglés partially ordered set) con límites, para reducir el tamaño de conjunto de filtros (compresión equivalente). Por estas razones, es necesario implementar un contenedor abstracto de retículo, y evaluar su desempeño tanto en la teoría, como en la práctica, para la solución de la distensibilidad del conjunto de filtros. Retículo (Lattice) es una estructura importante de Álgebra Abstracta, comúnmente se utiliza para resolver el problema teórico, y apenas de ser un contenedor abstracto en la ciencia de software, como resultado de su implementación compleja que proviene de su trivialidad en álgebra. Y por eso se hace difícil mi trabajo. Con el fin de evitar la teoría compleja del sistema práctico, simplemente introduce su núcleo algoritmo, el algoritmo de conteo, y esto llevó a cabo con el problema - la distensibilidad del conjunto de filtros. A continuación, se investigó la solución posible con retículos en la teoría, y se obtuvo el diseño de la implementación, normas para las pruebas xUnit y par´ametros para la evaluación. Por último, señalamos el entorno, el resultado, el análisis y la conclusión de la prueba de rendimiento.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

New telecom wavelength sources of polarization entangled photon pairs allow the distribution of entanglement through metro-access networks using standard equipment. This is essential to ease the deployment of future applications that can profit from quantum entanglement, such as quantum cryptography.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The inbound logistic for feeding the workstation inside the factory represents a critical issue in the car manufacturing industry. Nowadays, this issue is even more critical than in the past since more types of car are being produced in the assembly lines. Consequently, as workstations have to install many types of components, they also need to have an inventory of different types of the component in a compact space. The replenishment is a critical issue since a lack of inventory could cause line stoppage or reworking. On the other hand, an excess of inventory could increase the holding cost or even block the replenishment paths. The decision of the replenishment routes cannot be made without taking into consideration the inventory needed by each station during the production time which will depend on the production sequence. This problem deals with medium-sized instances and it is solved using online solvers. The contribution of this paper is a MILP for the replenishment and inventory of the components in a car assembly line.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Recently, the cross-layer design for the wireless sensor network communication protocol has become more and more important and popular. Considering the disadvantages of the traditional cross-layer routing algorithms, in this paper we propose a new fuzzy logic-based routing algorithm, named the Balanced Cross-layer Fuzzy Logic (BCFL) routing algorithm. In BCFL, we use the cross-layer parameters’ dispersion as the fuzzy logic inference system inputs. Moreover, we give each cross-layer parameter a dynamic weight according the value of the dispersion. For getting a balanced solution, the parameter whose dispersion is large will have small weight, and vice versa. In order to compare it with the traditional cross-layer routing algorithms, BCFL is evaluated through extensive simulations. The simulation results show that the new routing algorithm can handle the multiple constraints without increasing the complexity of the algorithm and can achieve the most balanced performance on selecting the next hop relay node. Moreover, the Balanced Cross-layer Fuzzy Logic routing algorithm can adapt to the dynamic changing of the network conditions and topology effectively.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Underwater acoustic sensor networks (UASNs) have become more and more important in ocean exploration applications, such as ocean monitoring, pollution detection, ocean resource management, underwater device maintenance, etc. In underwater acoustic sensor networks, since the routing protocol guarantees reliable and effective data transmission from the source node to the destination node, routing protocol design is an attractive topic for researchers. There are many routing algorithms have been proposed in recent years. To present the current state of development of UASN routing protocols, we review herein the UASN routing protocol designs reported in recent years. In this paper, all the routing protocols have been classified into different groups according to their characteristics and routing algorithms, such as the non-cross-layer design routing protocol, the traditional cross-layer design routing protocol, and the intelligent algorithm based routing protocol. This is also the first paper that introduces intelligent algorithm-based UASN routing protocols. In addition, in this paper, we investigate the development trends of UASN routing protocols, which can provide researchers with clear and direct insights for further research.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In maritime transportation, decisions are made in a dynamic setting where many aspects of the future are uncertain. However, most academic literature on maritime transportation considers static and deterministic routing and scheduling problems. This work addresses a gap in the literature on dynamic and stochastic maritime routing and scheduling problems, by focusing on the scheduling of departure times. Five simple strategies for setting departure times are considered, as well as a more advanced strategy which involves solving a mixed integer mathematical programming problem. The latter strategy is significantly better than the other methods, while adding only a small computational effort.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A study of archival RXTE, Swift, and Suzaku pointed observations of the transient high-mass X-ray binary GRO J1008−57 is presented. A new orbital ephemeris based on pulse arrival-timing shows the times of maximum luminosities during outbursts of GRO J1008−57 to be close to periastron at orbital phase − 0.03. This makes the source one of a few for which outburst dates can be predicted with very high precision. Spectra of the source in 2005, 2007, and 2011 can be well described by a simple power law with high-energy cutoff and an additional black body at lower energies. The photon index of the power law and the black-body flux only depend on the 15–50 keV source flux. No apparent hysteresis effects are seen. These correlations allow us to predict the evolution of the pulsar’s X-ray spectral shape over all outbursts as a function of just one parameter, the source’s flux. If modified by an additional soft component, this prediction even holds during GRO J1008−57’s 2012 type II outburst.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

"Grant no. US NSF MCS75-21758."

Relevância:

20.00% 20.00%

Publicador:

Resumo:

"An environmental protection publication (SW-113) in the solid waste management series."

Relevância:

20.00% 20.00%

Publicador:

Resumo:

"Prepared by Surface Water Branch, Water Resources Division, Geological Survey, for Engineering Division, Soil Conservation Service, U.S. Department of Agriculture, as Project no. 4."

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Mode of access: Internet.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

At head of cover title: Generalized computer program.