A is a network of handheld (cell phones) in which each phone communicates with the by through a local antenna at a cellular base station (cell site). The coverage area in which service is provided is divided into a mosaic of small geographical areas called "cells", each served by a separate low power multichannel and antenna at a base station. All the cell phones within a cell communicate with the system thr.
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Electricity can be stored directly for a short time in capacitors, somewhat longer electrochemically in , and much longer chemically (e.g. hydrogen), mechanically (e.g. pumped hydropower) or as heat. The first pumped hydroelectricity was constructed at the end of the 19th century around in Italy, Austria, and Switzerland. The technique rapidly expanded during the 196.
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Central Asia has faced major energy and water security challenges. Technically, water from the Pamir and Tian Shan Mountain ranges could be sufficient to meet the needs of the countries in the region, if there.
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