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451.
某超限高层建筑结构分析与优化   总被引:1,自引:0,他引:1  
为有效控制平、立面超限高层结构的扭转效应,利用结构概念设计和程序计算分析,较为详细地介绍了一栋因建筑平面为蝶型而平面规则性超限的高层建筑进行结构分析和结构优化的全过程。通过调整结构平面布置、计算分析和设置适当的构造措施,使结构整体设计既满足了建筑功能的需要,又符合现行规范的要求,计算结果也证实了这一结论。该设计可供类似工程参考。  相似文献   
452.
Emerging sharing modes, like the consumer-to-consumer (C2C) sharing of Uber and the business-to-consumer (B2C) sharing of GoFun, have considerably affected the retailing markets of traditional manufacturers, who are motivated to consider product sharing when making pricing and capacity decisions, particularly electric car manufacturers with limited capacity. In this paper, we examine the equilibrium pricing for a capacity-constrained manufacturer under various sharing modes and further analyze the impact of capacity constraint on the manufacturer's sharing mode selection as well as equilibrium outcomes. We find that manufacturers with low-cost products prefer B2C sharing while those with high-cost products prefer C2C sharing except when the sharing price is moderate. However, limited capacity motivates manufacturers to enter into the B2C sharing under a relatively low sharing price, and raise the total usage level by sharing high-cost products. We also show that the equilibrium capacity allocated to the sharing market with low-cost products first increases and then decreases. Finally, we find that sharing low-cost products with a high limited capacity leads to a lower retail price under B2C sharing, which creates a win-win situation for both the manufacturer and consumers. However, sharing high-cost products with a low limited capacity creates a win-lose situation for them.  相似文献   
453.
Capacity providers such as airlines often sell the same capacity to different market segments at different prices to improve their expected revenues. The absence of a secondary market, due to the nontransferability of airline tickets, gives rise to an opportunity for airlines to broker capacity between consumers with different willingness to pay. One way to broker capacity is by the introduction of callable products. The idea is similar to callable bonds where the issuer has the right, but not the obligation, to buy back the bonds at a certain price by a certain date. The idea of callable products was introduced before under the assumption that the fare-class demands are all independent. The independent assumption becomes untenable when there is significant demand recovery (respectively, demand cannibalization) when lower fares are closed (respectively, opened). In this case, consumer choice behavior should be modeled explicitly to make meaningful decisions. In this paper, we consider a general consumer choice model and develop the optimal strategy for callable products. Our numerical study illustrates how callable products are win-win-win, for the capacity provider and for both high and low fare consumers. Our studies also identify conditions for callable products to result in significant improvements in expected revenues.  相似文献   
454.
我国民用运力资源丰富.自2020年7月1日零时起,预备役部队全面纳入军队领导体制,改由党中央、中央军委集中统一领导.在此背景下,本文对民用运力动员的含义进行了深入剖析,分析了民用运力动员的主要任务和战区陆军部队对民用运力动员的要求,指出了预备役部队民用运力动员所面临的矛盾和困难,提出了推进民用运力动员的几点对策,如健全...  相似文献   
455.
结合自己的工作实践 ,分析建筑消防设计审核工作的重要性 ,并对如何加强建筑消防设计审核工作提出了看法。  相似文献   
456.
The search continues for methods to improve security for development in Sub-Saharan Africa. One of the important actors in this security arena is Sub-Saharan African governments’ armies. Much of their capability to meet security challenge depends on how militarily professional they are. The wave of democratic evolution in Africa since 1990 also affected military professionalism. This article reviews three models for assessing how democratisation might affect military professionalism in Sub-Saharan Africa, with special attention to post-conflict states. This should make it possible to decide which analytical methods are most appropriate to measure military professionalism in the particular circumstances of Sub-Saharan African post-conflict democratisation. Depending upon the particular nation-state in question, this decision on analytical methods may be useful for other Sub-Saharan states as well.  相似文献   
457.
This article studies flexible capacity strategy (FCS) under oligopoly competition with uncertain demand. Each firm utilizes either the FCS or inflexible capacity strategy (IFCS). Flexible firms can postpone their productions until observing the actual demand, whereas inflexible firms cannot. We formulate a new asymmetrical oligopoly model for the problem, and obtain capacity and production decisions of the firms at Nash equilibrium. It is interesting to verify that cross‐group competition determines the capacity allocation between the two groups of firms, while intergroup competition determines the market share within each group. Moreover, we show that the two strategies coexist among firms only when cost differentiation is medium. Counterintuitively, flexible firms benefit from increasing production cost when the inflexible competition intensity is sufficiently high. This is because of retreat of inflexible firms, flexibility effect, and the corresponding high price. We identify conditions under which FCS is superior than IFCS. We also demonstrate that flexible firms benefit from increasing demand uncertainty. However, when demand variance is not very large, flexible firms may be disadvantaged. We further investigate the effects of cross‐group and intergroup competition on individual performance of the firms. We show that as flexible competition intensity increases, inflexible firms are mainly affected by the cross‐group competition first and then by the intergroup competition, whereas flexible firms are mainly affected by the intergroup competition. Finally, we examine endogenous flexibility and identify its three drivers: cost parameters, cross‐group competition, and intergroup competition. © 2017 Wiley Periodicals, Inc. Naval Research Logistics 64: 117–138, 2017  相似文献   
458.
Whether military spending is capable of promoting social welfare is currently a controversial issue. The aim of this paper is to investigate how military spending affects the input and output of social welfare (i.e. social welfare expenditures and social welfare index). A panel cointegration analysis and an impulse response function are conducted with multi-country panel data, over two time periods, 1998–2011 and 1993–2007. In addition, to extend a comparative analysis over different economies, BRICS (i.e. Brazil, Russia, India, China, South Africa) and G7 (i.e. the US, Japan, Germany, the UK, France, Italy, Canada) countries are selected as representatives of emerging economies and developed countries, respectively. The empirical results show that military spending enhances social welfare expenditures in developed countries, while the effect is ambiguous in emerging economies. Also, military spending is capable of promoting the social welfare index based on the FMOLS estimation. The comparative analyses indicate that unlike in the G7, the effect of the growth of military spending on the growth of social welfare expenditures is negative and shorter in the BRICS.  相似文献   
459.
The study examines the effect of noncognitive skills on early career choices among young job seekers. Specifically, we analyze the influence of personality traits on the decision by military applicants either to choose the military or a civilian career option. We use a unique micro-level data-set of applicants to the US Navy and exploit the fact that many individuals who initially apply for military jobs eventually choose civilian careers instead. In this institutional setting, job candidates use new information to update their beliefs about the military job match. Personality traits are viewed as productive abilities that influence applicants’ expectations about the economic return to the job and occupational training offered by the Navy. The study finds that many of the 15 lower order personality facets associated with the Big Five traits are predictive of applicants’ job choices and provides suggestive evidence of a link between personality traits, job match expectations, and career choice.  相似文献   
460.
China’s rapid economic growth is facilitating massive increases in its military spending and causing increased security concerns in Asia and the Western Pacific. But there is uncertainty over how large China’s military spending is relative to other countries, or how fast it is growing in real terms. We address this issue by deriving a relative military cost price index based on the relative unit costs of inputs. We find that China’s real military spending is much larger than suggested by exchange rate comparisons, and even larger than standard purchasing power parity comparisons. We also find, however, that the real growth of China’s military spending has been smaller than conventionally thought. This is due to rapidly growing wages in China and the large share of personnel in China’s military budget.  相似文献   
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