Light attenuation in marine ecosystems can limit primary production and determine the species composition and abundance of primary producers. In Florida Bay, the importance of understanding the present light environment has heightened as major upstream water management restoration projects have been proposed and some are already being implemented. We analyzed a 2-yr (2001–2003) data set of the ...

drought monitoring is a fundamental component of drought risk management. it is normally performed using various drought indices that are effectively continuous functions of rainfall and other hydrometeorological variables. in many instances, drought indices are used for monitoring purposes. geostatistical methods allow the interpolation of spatially referenced data and the prediction of values...

the variability of temperature and precipitation is regarded as one of the main characteristics of the climate.precipitation and its results, especially results such as droughts, vary on different temporal and spatial scales. thepurpose of this paper is to determine the frequency of the inter-annual variability of the driest month in north-westiran. in order to obtain the best results, we used ...

a hybrid hydro/wind/photovoltaic base on hydrogen storage system is designed to supply power demand of pump stations. the aim of this design is minimization of net present cost of the hybrid system. optimization problem is subject to reliable supply of the demand. the system is investigated in the north west of iran (meshkinshahr) and the local data is applied. about 12 pump stations are found ...

Information systems consist of multiple mobile stations and xed stations communicating with each other. Mission critical applications are required to be executed fault-tolerantly in these systems. However, mobile stations support neither enough volume of storage and processing power nor enough capacity of battery to do reliable communication for a long period. Moreover, wireless communication c...

In order to extract any ULF signature associated with earthquakes, the principal component analysis (PCA) and singular spectral analysis (SSA) have been performed to investigate the possibility of discrimination of signals from different sources (geomagnetic variation, artificial noise, and the other sources (earthquake-related ULF emissions)). We adopt PCA to the time series data observed at c...

One of the main features of IEEE 802.16m is the relay transmission which could not only extend the service coverage, but also improve the quality-of-service (QoS) to the mobile stations. In this paper, we consider the cooperation among relay stations and mobile stations to improve the performance of relay transmission in IEEE 802.16m network. In this case, the relay stations and mobile stations...

The function of a power station is to deliver power to a large number of consum ers. However, the power demands of different consumers vary in accordance with their activities. The result of this variation in demand is that load on a power station is never constant, rather it varies from time to time. Most of the complexities of modern power plant operation arise from the inherent variability o...

In ad hoc wireless LANs populated by mutually impenetrable groups of anonymous stations, honest stations are prone to "bandwidth stealing" by selfish stations. The problem is addressed at the MAC level by postulating that (i) honest stations use a carefully designed contention strategy teaching selfish stations that the best reply is to stick to the same strategy, and (ii) a verifiable winner p...