introduction: agriculture as one of old sectors of economy has been important role in the supply food for peoples and raw materials. globalization causes rapid growth of world trade and reduces information and communications costs. globalization and rapid growth of trade increases the potential benefits of trade for agriculture from various aspects. the potential benefits of trade for agricultu...

Macroeconomics was born as a distinct field in the 1940s, as a part of the intellectual response to the Great Depression. The term then referred to the body of knowledge and expertise that we hoped would prevent the recurrence of that economic disaster. My thesis in this lecture is that macroeconomics in this original sense has succeeded: Its central problem of depression-prevention has been so...

Using data from a two-year randomized pricing experiment in China, we study the impact and design of subsidy policies for weather insurance. Results show that subsidies are effective in boosting demand in the short-run but not in the longer term. Exploring the channels, we show that while subsidies increase the direct and social effects of payout experiences by enlarging coverage, they also dam...

as an industrial crop, sugar beet plays an important role in meeting domestic demand for sugar. given the higher level of imported sugar iniran, the application of protectionist policies is an approach for supplying required sugar. one of these policies is technological improvement. in order to study the effect of this policy, sugar beet supply and demand equations in 1971-2008 were fitted by t...

A central question in designing server farms today is how to efficiently provision the number of serversto handle unpredictable demand patterns, so as to extract the best performance while not wastingenergy. While one would like to turn servers off when they become idle to save energy, the largesetup cost (both, in terms of setup time and energy penalty) needed to switch the server ...

A central question in designing server farms today is how to efficiently provision the number of serversto handle unpredictable demand patterns, so as to extract the best performance while not wastingenergy. While one would like to turn servers off when they become idle to save energy, the largesetup cost (both, in terms of setup time and energy penalty) needed to switch the server ...

In this paper we describe an XML-based platform for dynamic active node policy updates. XML supports the definition of specific policy languages, their extension to satisfy new needs and the management of deployed policies on different active nodes. We show an example of the management of router packet forwarding policies where the XML policies that drive the packet routing are updated at run-t...