With increasing demand of new wireless applications and increasing number of wireless user’s problem of spectrum scarcity arises. Cognitive Radio technology supports dynamic spectrum access to address spectrum scarcity problem. Reliability of cognitive operation entirely depends upon how effectively task of spectrum sensing has been performed. Spectrum sensing is a process of discovering voids ...

Metrics of water scarcity and stress have evolved over the last three decades from simple threshold indicators to holistic measures characterising human environments and freshwater sustainability. Metrics commonly estimate renewable freshwater resources using mean annual river runoff, which masks hydrological variability, and quantify subjectively socio-economic conditions characterising adapti...

Freshwater scarcity is a growing concern, placing considerable importance on the accuracy of indicators used to characterize and map water scarcity worldwide. We improve upon past efforts by using estimates of blue water footprints (consumptive use of ground- and surface water flows) rather than water withdrawals, accounting for the flows needed to sustain critical ecological functions and by c...

The Policy Research Working Paper Series disseminates the findings of work in progress to encourage the exchange of ideas about development issues. An objective of the series is to get the findings out quickly, even if the presentations are less than fully polished. The papers carry the names of the authors and should be cited accordingly. The findings, interpretations, and conclusions expresse...

Abstract – In online multimedia systems resources (e.g. network capacity) are to be evenly distributed among clients. These clients, however, usually have different QoS needs, and thus their actual capacity demands may vary considerably. In such context even distribution is not possible, but fair distribution, based on subjective client satisfaction must be achived instead. In this paper a new ...

1. Abstract The next generation wireless networks are envisioned to deal with the expected thousandfold increase in total mobile broadband data and the hundred-fold increase in connected devices. In order to provide higher data rates, improved endto-end performance, low latency, and low energy consumption at low cost per transmission, the fifth generation (5G) systems are required to overcome v...

Assuming the abc-conjecture we show that there are only nitely many powerful binomial coeecients ? n k with 3 k n=2; in fact, that if q 2 divides ? n k that q n 2 ? n k o(1). Unconditionally we show that there are N 1=2+o(1) powerful binomial coeecients in the top N rows of Pascal's Triangle.

This paper studies whether labor scarcity encourages technological advances, i.e., technology adoption or innovation, for example, as claimed by Habakkuk in the context of 19th-century United States. I de…ne technology as strongly labor saving if technological advances reduce the marginal product of labor and as strongly labor complementary if they increase it. I show that labor scarcity encour...

Abstract The global climate changes and their influence on agriculture in Uzbekistan were analyzed, including problems of irrigation water shortage irrigated lands the lower reaches Amu Darya with greatest due to repeated dry years. Additionally, recommendations for effective use resources conditions meadow alluvial soils salinization shallow salinized groundwater proposed subirrigation drip ir...