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91.
92.
本文通过对2F4.8制冷压缩机热力过程的计算机模拟,获得气阀参数对压缩机热力性能影响的数据资料,以改进气阀结构。经过试验证明,可提高压缩机制冷量和性能系数10%以上。 相似文献
93.
94.
语篇连贯是语篇与非语篇的最大区别 ,韩礼德和哈桑把语篇的显性衔接看作是连贯的必要前提条件 ,本文对此作了批评 ,并以斯佩尔和威尔逊的关联理论为基点 ,集中讨论用关联认知方法构建连贯的语篇。 相似文献
95.
Russia’s role in ‘animation’ of the Kyoto Protocol was crucial. Its initial vacillation on ratification was predominantly
due to political bargaining with the EU. Domestic economic rationales [i.e. impacts of emission trading and Joint Implementation
(JI) projects] were important to a much lesser extent and environmental motives did not seem to play any role in the decision.
Since the Protocol entered into force, there have been significant delays in complete establishment of policy implementation
frameworks, which are necessary for Russia to start benefiting from JI and emission trading. Only recently, in 2007, have
GHG inventories and a national registry been established and the responsibilities for implementation of the Protocol and JI
among the government departments have been distributed only to a certain extent. Some constraints hindering JI projects, such
as vague legislation, an unfavourable economic climate, lack of commitment to JI projects, corruption, xenophobia, state and
agency ‘capture’ still remain.
相似文献
96.
Laura Bernardi Andreas Klärner Holger von der Lippe 《Revue europeenne de demographie》2008,24(3):287-313
This article contributes to the ongoing debate on the economic determinants of fertility behavior by addressing the role of
job insecurity in couples’ intentions concerning parenthood and its timing. It starts from the hypothesis that cultural values
moderate individuals’ reactions to job insecurity and the way it is related to family formation. With a systematic thematic
content analysis of a set of semi-structured interviews with childless men and women around the age of 30 in eastern and western
Germany, we are able to show that there are substantial differences in the consequences of job insecurity on intentions to
have a first child. In western Germany, a relatively secure job career is expected to precede family formation, and this sequence
of transitions is rather rigid, whereas in eastern Germany job security and family formation are thought of and practiced
as parallel investments. We suggest that the lack of convergence in family formation patterns between eastern and western
Germany after the unification of the country in 1990 is partially related to different attitudes toward job insecurity in
the two contexts. 相似文献
97.
98.
Michael Kohler 《AStA Advances in Statistical Analysis》2008,92(2):153-178
American options in discrete time can be priced by solving optimal stopping problems. This can be done by computing so-called
continuation values, which we represent as regression functions defined recursively by using the continuation values of the
next time step. We use Monte Carlo to generate data, and then we apply smoothing spline regression estimates to estimate the
continuation values from these data. All parameters of the estimate are chosen data dependent. We present results concerning
consistency and the estimates’ rate of convergence. 相似文献
99.
This paper proposes an experimental test to evaluate the performance of the serial cost sharing rule, originally proposed
by Shenker [Sigmetrics, 241–242 (1990)] and then analyzed by Moulin and Shenker [Econometrica 60, 1009–1037 (1992)]. We report
measures of the performance and efficiency of the serial mechanism by comparing the choices and payoffs attained by the subjects
to the expected equilibrium allocations. Experimental evidence shows that learning is needed for the subjects to converge
to the equilibrium strategy. However, in terms of efficiency, the serial mechanism leads to almost efficient allocations. 相似文献
100.