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81.
Political targets for implementing the German “energy turnaround” aiming at the ambitious extension of renewable energies to generate electricity. However, a majority of the renewable supply is provided by intermittent sources, e.g. wind and solar power. For balancing the increasing supply fluctuations additional storage options are claimed beside of an enforced grid infrastructure and a more flexible demand side. Despite of the political guidelines the economics of additional flexibility measures has to be considered. For this paper we analyse the costs of large scale stationary battery storages to be operated in wholesale markets and transmission grid level. By deriving a key figure based on a life-cycle cost approach, we are able to evaluate the additional costs of electricity of selected battery technologies (lead-acid, lithium ion, sodium sulphur, redox-flow). Moreover, current and valid parameters of the cost analysis are received by scientific and industrial stakeholders of battery systems via online survey and face-to-face interviews. According to the stakeholder estimation a nationwide operation of stationary battery storages will be established at wholesale and transmission grid level until the year 2030. The life-cycle cost analysis, which also includes estimated future cost reductions, shows that lead-acid batteries remain the cost-efficient technology, assuming about 100 storage cycles p.a. In addition, a sensitivity analysis reveals the impact of increasing annual storage cycles as well as the achievable cost reduction by economies-of-scales of the power unit of the storage system.  相似文献   
82.
Managing new product development (NPD) with a global point of view is argued to be essential in current business more than ever. Accordingly, many firms are trying to revitalize their NPD processes to make them more global. Therefore, examining global NPD management is one of the top priorities for research. While scholars have examined global launch management, there has been scant attention on the direct effect of global discovery management on NPD success. Therefore, this study investigates how a globally managed discovery phase enhances a firm's overall NPD success. Drawing upon the resource‐based view (RBV) and using Kotabe's ( 1990 ) generic model for market success in global competition as the overarching framework, this study examines four drivers of NPD success: global discovery management, the firm's “global footprint,” its inbound knowledge sourcing practices (i.e., “open innovation proclivity”), and nationality of the teams (i.e., “cross‐national global NPD team use”). The hypotheses are tested using a sample of 255 business units from multiple industries, headquartered worldwide, and surveyed during the 2012 PDMA Comparative Performance Assessment Study (CPAS). The PLM‐SEM analyses show that, of the four drivers examined, only global discovery management strongly influences a firm's NPD program success. The findings enhance our understanding of the particularities in global NPD. Based on the study's results, suggestions are provided as to how multinationals can leverage their international operations in the course of their front‐end activities.  相似文献   
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This paper explores the economic implications of different contract durations in markets for on-line (primary and secondary) reserve capacity in Germany with the crucial feature of separate markets for spot energy and reserve capacity provision. The analysis is based on an equilibrium model developed by Just and Weber (Energy Econo 30:3198–3221, 2008) for reserve markets. It reveals the implicit trade-off for the bidders and implicit interdependencies between the reserve and the spot markets. Even if the markets are not explicitly coordinated, they are interrelated through the dispatch decisions of the power plant owners. The paper concludes that the current German reserve market design is inefficient and should be improved. The results clearly show that shorter periods (with resulting lower variations in overall electricity demand) lead to more efficient dispatch and market results. Not only prices in the reserve capacity markets are expected to be lower, but also spot market prices. As these benefits can be partially reaped by owners of large generation portfolios also under longer contract durations, it discriminates against smaller generation companies and can potentially deter market participation. Further, the paper takes a broader perspective and discusses security concerns against shorter contract durations. It is shown that the opportunity costs character of the reserve market implies sufficient incentives for supplying online reserve capacity. The concerns do not appear to be predominant and it should be possible to manage them appropriately.  相似文献   
85.
The demographic change and its consequences forces citizens of Germany to realign towards private insurance products. This decision should be based on structured analyses. Most recent studies were inconclusive regarding this decision.As investments are commonly compared using average developments of the underlying, the possibility to switch the underlying during the duration of the investment, they are not represented accordingly and therefore bias the results of the calculation. We perform a thorough simulation analysis to compare two competing investments for retirement provisions while respecting additional costs and tax implications of switching.Without any switching the evaluation of other studies is generally verified (pure investment beats insurance product). But as soon as switching is implemented the tax advantage of insurance products is overcompensating the cost advantage of a pure investment solution. Further research should aim in this direction.  相似文献   
86.
Using a large international sample of 35 developed and emerging markets, we analyze whether Islamic indices exhibit a different performance to conventional benchmarks. While there is no compelling evidence of performance differences in robust Sharpe ratio tests and after controlling for market risk, we find a significantly positive four-factor alpha for the aggregate developed markets region. This outperformance stems, however, mainly from the U.S. and is largely attributable to the exclusion of financial stocks in Sharia-screened portfolios. As the extensive downturn of financials is related to the recent financial crisis, we do not argue that this outperformance will continue over time. The style analysis reveals that Islamic indices invest mainly in growth stocks and positive momentum stocks. This, for a passive portfolio intriguing result can, however, be explained by the strong sector allocation towards energy firms and their strong momentum characteristic during the sample period.  相似文献   
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In this article, we hypothesize that leaders who display group-oriented values (i.e., values that focus on the welfare of the group rather than on the self-interest of the leader) will be evaluated more positively by their followers than leaders who do not display group-oriented values. Importantly, we expected these effects to be more pronounced for leaders who are ingroup members (i.e., stemming from the same social group as their followers) than for leaders who are outgroup members (i.e., leaders stemming from a different social group than their followers). We tested our hypotheses in two studies. Results of a field study (N = 95) showed the expected relationship between leaders’ group-oriented values and followers’ identification with their leaders. A scenario study (N = 137) replicated the results and extended it to followers’ endorsement of their leaders. Overall, these findings suggest that displaying group-oriented values pays off more for ingroup than for outgroup leaders.  相似文献   
90.
This article investigates the relationship between a debtor country's external financial indicators and the costs associated with the insurance of export credits to that country. For this purpose a stylized model of export credit insurance (ECI) is developed, the central idea being that ECI is similar to a contingent claim such as a European put option. Thus, tools from option pricing theory were used to calculate the price of ECI, implying that not only the current financial position but also the volatility of the changes in that position determine such costs. The empirical results of a statistical analysis of the premium rates for ECI, applied by a private export credit insurer to seventy-seven developing countries during 1993, provide some support for these hypotheses. In particular, the reserves-over-imports ratio of a debtor country and the volatility of the rates of change of this ratio appear to contribute significantly to the premium rates that apply to that country. Thus, the article provides evidence that option pricing parameters do play role in practical insurance pricing, even if this pricing is not explicitly based on these parameters. Premium rates are set as if an underlying option market operated. Thus, the trade of countries with volatile external financial positions is saddled with higher costs than that of countries with more stable positions.  相似文献   
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