Abstract: A typical reliability engineering problem regarding communication satellites has been considered to determine redundancy allocation scheme of power amplifiers within payload transponder module, whose dominant function is to amplify power levels of the received signals from the Earth, through maximizing reliability against mass, power, and other technical limitations. Adding each redundant power amplifier component increases not only reliability but also hardware, testing, and launch cost of a satellite. This study investigates a multi-objective approach used in order to solve Redundancy Allocation Problem (RAP) for a communication satellite payload transponder, focusing on design cost due to redundancy and reliability factors. The main purpose is to find the optimum power amplifier redundancy configuration satisfying reliability and capacity thresholds simultaneously instead of analyzing respectively or independently. A mathematical model and calculation approach are instituted including objective function definitions, and then, the problem is solved analytically with different input parameters in MATLAB environment. Example results showed that payload capacity and failure rate of power amplifiers have remarkable effects on the solution and also processing time.
Abstract: In recent decade's tourism industry is one of main
reasons of the social and economical development for many
countries; so these countries try to gain more portion of it for
themselves. The excessive natural and cultural touristy potentialities
in Iran made this country to be one of the most attractive sightseeing
areas, although; Iran has got the lowest rate of tourists. Khark Island
is about 32 km. It is a beautiful coral reef coast; about 98% of oil
export has been done through this place. The ecotourism
potentialities of Khark and Kharko Islands (about 3.7km far from
Khark) are the reason to consider ecotourism and the main activity in
these islands which is exporting oil at the same time. This article
refers to way of measuring the geographical coordination of the
place, and the potentialities, ecotourism attraction of the islands and
introduces some ideas in order to expand tourism in the islands.