In this paper we propose a new routing protocol called virtual sink rotation (VSR) routing for large-scale sensor networks. VSR can efficiently handle a large number of sources as well as a large number of sinks with potential mobility. Each sensor node is not required to know the global network topology nor the location awareness. The main ideas underlying the VSR are two folds. First, to alle...

We investigate the effect of a directional antenna in wireless sensor networks from the perspective of network lifetime extension. Previous studies on wireless sensor networks have assumed only an omni-directional antenna model, since a directional antenna has been considered inappropriate for sensors due to size and cost constraints. In this sense, we propose to mount the directional antenna o...

We investigate out-of-equilibrium stationary processes emerging in a Discrete Nonlinear Schrödinger chain in contact with a heat reservoir (a bath) at temperature TL and a pure dissipator (a sink) acting on opposite edges. We observe two different regimes. For small heat-bath temperatures TL and chemical-potentials, temperature profiles across the chain display a non-monotonous shape, remain re...

In this, the second of a two-part paper, the analysis of the apparent frequency of a seven-story reinforced-concrete hotel building in Van Nuys, Calif., is extended to consider its time-dependent changes, both short and long term. The instantaneous apparent frequency is measured by two methods: windowed Fourier analysis and zero-crossings analysis. The results show that it changes from earthqua...

In Wireless sensor networks the major concern is how to conserve the nodes' energy so that network lifetime can be extended significantly. Employing one static sink can rapidly exhaust the energy of sink neighbors. Furthermore, using a non-optimal single path together with a maximum transmission power level may quickly deplete the energy of individual nodes on the route. This all results in unb...

Establishing an energy efficient wireless sensor network is a challenging task. A significant amount of research work has already been carried out in this direction to study energy optimization in WSN by taking the advantage of mobile sink or mobile agents. Many approaches using mobile sink have demonstrated that energy usage can be optimized significantly in the phenomenon area from where the ...

Improving the efficiency of data dissemination algorithms and protocols to mobile sink remains as an interesting research and engineering issue, especial for large-scale wireless sensor network. As the node energy and resources are limited, theses protocols should meet energyefficiency, low delay and high delivery ratio requirements. Although an energy-efficient dissemination tree (d-tree) can ...

The thermodynamical property of a small cluster including M Hubbard dimers, each of which is described by the two-site Hubbard model, has been discussed within the nonex-tensive statistics (NES). We have calculated temperature and magnetic-field dependences of the specific heat and susceptibility for M = 1, 2, 3 and ∞, assuming the relation between M and the entropic index q given by q = 1 + 1/...

Due to the battery resource constraint, it is a critical issue to save energy in wireless sensor networks, particularly in large sensor networks. One possible solution is to deploy multiple sink nodes simultaneously. In this paper, we propose a protocol called MRMS (Multipath Routing in large scale sensor networks with Multiple Sink nodes) which incorporates multiple sink nodes, a new path cost...