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1.
�ҹ���Ȼ���۸����״���ĸ﷽���̽ 总被引:9,自引:6,他引:3
当今世界各国执行的商品天然气定价原则主要包括完全成本原则、平均利润原则、长期边际成本定价原则、比价合理原则和供求平衡原则等。文章分析了我国天然气价格的演变历史及现状,说明了现行价格形成的制度原因。研究了天然气商品从生产到运输再到销售各环节的价格确定方法,以此为基础给出了一个即考虑天然气商品价值又考虑竞争和政府管制因素的天然气商品的定价公式。文章最后指出,在真正的、完全竞争的天然气市场建立之前,商品天然气的价格主要应按完全成本原则进行确定。 相似文献
2.
今年上半年我国石油工业基本保持平稳、健康的发展格局:油气产量和消费需求均持续增长,油气开采业大幅盈利,原油加工业仍然亏损,投资大幅度增长,原油进口依存度加大。下半年需要采取的应对措施是:进一步完善成品油价格形成机制;规范和引导上海石油交易所健康运行;加强天然气管理,作好需求预测;实施石油替代激励政策。预计下半年国际油价继续走高的可能性较大;我国全年石油表观消费可能会突破3亿吨,进口依存度继续在40%以上。 相似文献
3.
Indian electric tariffs are characterized by very high rates for industrial and commercial classes to permit subsidized electric consumption by residential and agricultural customers. We investigate the viability of this policy using monthly data for 1997–2003 on electric consumption by a few large industrial customers under the aegis of a small distribution company in the state of Uttar Pradesh. For a given price/cost ratio, it can be shown that if the cross-subsidizing class’ electricity demand is sufficiently elastic, increasing the class’ rates fail to recover incremental cross-subsidy necessary to support additional revenues for subsidized classes. This suboptimality is tested by individually estimating time-variant price-elasticities of demand for these industrial customers using Box-Cox and linear regressions. We find that at least for some of these customers, cross-subsidy was suboptimal prior to as late as October 2001, when rates were changed following reforms. 相似文献
4.
本文分别对进口和国产品牌不同种类的水质分析仪表的市场应用、市场份额、价格、技术指标等进行详细调研和比较,旨在为电站运行选用经济适用的水质分析仪表提供选择指导。 相似文献
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介绍了油田经济开发期的概念,给出了原油价格与经济开发期之间的定量关系,在不同的原油价格下计算了某油田经济开发期,说明原油价格直接影响油田的经济开发期。 相似文献
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A natural generalization of the selfish routing setting arises when some of the users obey a central coordinating authority,
while the rest act selfishly. Such behavior can be modeled by dividing the users into an α fraction that are routed according to the central coordinator’s routing strategy (Stackelberg strategy), and the remaining 1−α that determine their strategy selfishly, given the routing of the coordinated users. One seeks to quantify the resulting
price of anarchy, i.e., the ratio of the cost of the worst traffic equilibrium to the system optimum, as a function of α. It is well-known that for α=0 and linear latency functions the price of anarchy is at most 4/3 (J. ACM 49, 236–259, 2002). If α tends to 1, the price of anarchy should also tend to 1 for any reasonable algorithm used by the coordinator.
We analyze two such algorithms for Stackelberg routing, LLF and SCALE. For general topology networks, multicommodity users,
and linear latency functions, we show a price of anarchy bound for SCALE which decreases from 4/3 to 1 as α increases from 0 to 1, and depends only on
α. Up to this work, such a tradeoff was known only for the case of two nodes connected with parallel links (SIAM J. Comput.
33, 332–350, 2004), while for general networks it was not clear whether such a result could be achieved, even in the single-commodity case.
We show a weaker bound for LLF and also some extensions to general latency functions.
The existence of a central coordinator is a rather strong requirement for a network. We show that we can do away with such
a coordinator, as long as we are allowed to impose taxes (tolls) on the edges in order to steer the selfish users towards
an improved system cost. As long as there is at least a fraction α of users that pay their taxes, we show the existence of taxes that lead to the simulation of SCALE by the tax-payers. The
extension of the results mentioned above quantifies the improvement on the system cost as the number of tax-evaders decreases.
Research of G. Karakostas supported by an NSERC Discovery Grant and MITACS.
Research of S. Kolliopoulos partially supported by the University of Athens under the project Kapodistrias. 相似文献
10.
Martin Hoefer 《Algorithmica》2009,53(1):104-131
In this paper we consider the connection game, a simple network design game with independent selfish agents that was introduced by Anshelevich et al. (Proc. 35th Ann.
ACM Symp. Theo. Comp. (STOC), pp. 511–520, 2003). Our study concerns an important subclass of tree games, in which every feasible network is guaranteed to be connected. It generalizes the class of single-source games considered
by Anshelevich et al. We focus on the existence, quality, and computability of pure-strategy exact and approximate Nash equilibria.
For tree connection games, in which every player holds two terminals, we show that there is a Nash equilibrium as cheap as
the optimum network. In contrast, for single-source games, in which every player has at most three terminals, the price of
stability is at least k−2, and it is
-complete to decide the existence of a Nash equilibrium. Hence, we propose polynomial time algorithms for computing approximate
Nash equilibria, which provide relaxed stability and cost efficiency guarantees. For the case of two terminals per player,
there is an algorithm to find a (2+ε,1.55)-approximate Nash equilibrium. It can be generalized to an algorithm to find a (3.1+ε,1.55)-approximate Nash equilibrium for general tree connection games. This improves the guarantee of the only previous algorithm
for the problem, which returns a (4.65+ε,1.55)-approximate Nash equilibrium. Tightness results for the analysis of all algorithms are derived. Our algorithms use
a novel iteration technique for trees that might be of independent interest.
This work has appeared in part as an extended abstract at the 31st Symposium on Mathematical Foundations of Computer Science
(MFCS 2006) and the 17th International Symposium on Algorithms and Computation (ISAAC 2006).
Supported by DFG Research Training Group 1042 “Explorative Analysis and Visualization of Large Information Spaces”. 相似文献