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201.
Abuse of authority is an unsolved problem in the new institutional theory of the firm. This paper attempts a double attack to this problem by developing a contractarian view of corporate codes of ethics. From the ex-ante standpoint the paper elaborates on the idea of a Social Contract based on Co-operative Bargaining Games and deduces from it the fair/efficient 'Constitution' of the firm endorsed by means of a well-devised corporate code of ethics. From the ex-post standpoint, codes of ethics are proved to be self-enforcing norms, by showing how they put at work the mechanism of a Repeated Game of Reputation within hierarchical transactions (firms) characterised by incomplete contracts and unforeseen events. To accomplish this task a theory of rationality in the face of unforeseen contingencies is sketched by working out the idea that the domain of a principle of ethics defines a fuzzy event, i.e. an event to which also the ex-ante unforeseen, unimaginable states of the world belong to a certain degree.  相似文献   
202.
In our research we propose a market formalization of secondary trading of airport slots. This proposed market is managed through an individual rational and budget balanced combinatorial slot exchange. The suggested market mechanism allows consideration of en-route sector capacities during the slot allocation process. We quantify the potential advantage of the market by comparing it with current practice. The results show that solutions that appear optimal when neglecting en-route sector capacities can be infeasible when taking capacities into account. Finally, in the proposed market the existence of grandfather rights does not seem to affect airline costs in a significant way.  相似文献   
203.
Abstract

Aims: Prophylaxis with standard-acting recombinant factor IX (rFIX) in hemophilia B patients requires frequent injections. Extended half-life (EHL) products allow for prolonged dosing intervals, and so reduce this treatment burden. Three technologies are employed to extend the half-life of FIX; glycopegylation, Fc-fusion, and albumin fusion. rIX-FP is a novel albumin fusion protein, which allows for a prolonged dosing interval of up to 14?days. A systematic review and indirect statistical comparison was performed to evaluate the efficacy of both EHL and standard-acting rFIX products compared with rIX-FP in Phase III trials for prophylaxis in adult hemophilia B patients.

Materials and methods: A systematic search was conducted in both EMBASE and PubMed to identify Phase III trials of prophylactic rFIX treatment in previously treated hemophilia B patients aged ≥12?years (FIX ≤2%). Annualized bleeding rate (ABR), spontaneous ABR (AsBR), and joint ABR (AjBR) data were extracted from each study. A z-test was performed using the mean of each parameter, and the mean difference in outcome between studies was calculated.

Results: Seven articles investigating six rFIX products were identified. Median ABR, AsBR, and AjBR ranged from 0–3.0, 0–1.0, and 0–1.1 (means = 0.8–4.26, 0.13–2.6, and 0.34–2.85), respectively. rIX-FP achieved the lowest median and mean values in all three parameters. Z-tests showed that mean ABR was significantly lower for rIX-FP 7-day prophylaxis compared with the majority of standard-acting and other EHL rFIX products.

Limitations: The low number of appropriate trials available for comparison limits the quantity of data available for comparison, and restricts the use of methods of adjustment for variance in study design or patient characteristics. However, these limitations are shared with similar analyses published in this field.

Conclusion: This indirect comparison of Phase III trials indicates that rIX-FP efficacy compares favorably vs other rFIX products for prophylaxis in hemophilia B.  相似文献   
204.
The main operational concept of Single European Sky ATM Research Programme is the notion of business trajectory. One possible implementation is based on the notion of a contract of objectives; an agreement among the main air traffic management actors on spatial and temporal intervals called target windows. These 4D windows are defined prior to flight departure by the airlines, airports and air navigation service providers to increase punctuality. We use an analytic hierarchy process to assess the opportunity of implementing this concept by considering the views of experts. The findings indicate that there are net benefits for airlines and air navigation service providers but not for airports  相似文献   
205.
The authors present tests of excess volatility of exchange rates which impose minimal structure on the data and do not commit to a choice of exchange rate "fundamentals." The method builds on existing volatility tests of asset prices, combining them with a procedure that extracts unobservable fundamentals from survey-based exchange rate expectations. The method is applied to data for the three major exchange rates since 1984, and broad evidence is given of excess volatility with respect to the predictions of the canonical asset-pricing model of the exchange rate with rational expectations.  相似文献   
206.
Solving transshipment problems to optimality is difficult, unless several simplifying hypotheses are assumed (such as unit-sized customer demands and replenishments, negligible replenishment lead time, etc.). For this reason, some heuristics have been recently proposed in order to provide rules, which incorporate relevant factors of the problem, to find conditions under which it makes sense to transship a certain number of units from one retailer to another. Most of these studies concern emergency transshipment, which means that shipments between locations can occur only when a shortage happens, and shipments are assumed to be fast enough to satisfy the location in shortage. When this assumption is not feasible, as in many real cases, transshipments between locations have to be performed before a shortage happens. The paper addresses this case, which can be named ‘preventive’ transshipment, where the inventory level of different locations at the same echelon is balanced through lateral shipments, before a shortage happens. A heuristic for deciding on transshipment policy (when to transship and how much), trying to minimise overall expected costs, is presented. A simulation study considering different scenarios is performed and results confirm the effectiveness of the heuristic.  相似文献   
207.
This paper analyzes the effects of the enlargements of the European Union on inequality using an approach based on individuals' lifecycle incomes. This allows one to consider the effect of different rates of growth and survival rates. Inequality in terms of permanent income was substantially less than in current per capita income at the time of all the enlargements except those of the last 10 years. The results point to the key role of policies that stimulate growth in the less developed countries. With an annual β‐convergence of 2% in current income, inequality in permanent income would be less than one third of what it is now.  相似文献   
208.
Over the past 20?years labour has become increasingly mobile and whilst employment and earnings effects in host countries have been extensively analysed, the implications for firm and industry performance have received far less attention. This paper explores the direct economic consequences of immigration on host nations?? productivity performance at a sectoral level in two very different European countries, Spain and the UK. Whilst the UK has traditionally seen substantial immigration, for Spain the phenomenon is much more recent. Our findings from a growth accounting analysis show that migration has made a negative contribution to labour productivity growth in Spain and a negative but negligible contribution in the UK. This difference is driven by a positive impact from migrant labour quality in the UK. This finding broadly holds across all sectors, but we note considerable variation in magnitudes. Labour productivity growth has a neutral contribution from migrant labour in construction and personal services in the UK, whilst in every case in Spain the effect is negative, most strongly in agriculture. Using an econometric approach to production function estimation we observe a positive long term effect on total factor productivity from migrant workers in the UK and a negative effect in Spain. Our findings suggest that either the UK is better at assimilating migrants or is more selective in terms of who is permitted to migrate.  相似文献   
209.
210.
Despite the growing interest in social entrepreneurship, there exist gaps in research that compares traditional business-oriented entrepreneurship with the social kind. This study attempts to fill the gap by answering the following questions: Are there significant differences between the survival chances of business and social ventures? and Do the traits of the entrepreneur and the firm play the same role as success factors for both types of venture? Hypotheses are tested using data collected from 2,179 firms. The results show that significant differences exist between social and business-oriented entrepreneurship in the form and intensity of the independent variables related to survival.  相似文献   
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