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81.
This paper presents the data of tensile strength of water in depression tank whichwere measured by small venturi during cavitation investigation of a series of real project models.These measurements show that in depression tank water has slight tensile strength in case of highvacuum.But it influences the incipient cavitation number.In tests we also studied the influenceof tensile strength on scale effect of cavitation models. 相似文献
82.
G. P. Zanias 《Journal of Agricultural Economics》1993,44(3):418-427
The degree of spatial market integration in European Community agricultural product markets is investigated. The methodology is based on co-integration analysis. A two-step testing procedure is applied to test the existence of the ‘Law of One Price’ which should be in force if these markets are truly integrated. The results show that market integration has not been achieved in a number of cases even when MCAs are subtracted from the price series used. 相似文献
83.
D. P. Kennedy 《Mathematical Finance》1993,3(1):55-63
For a compound Poisson process with negative drift and jump distribution consisting of a mixture of exponentials on [0) and on (-, 0), an exact expression is derived for the probability of hitting the level c, c > 0. the problem is motivated by modeling the returns from trading on financial markets. 相似文献
84.
A model describing the dynamics of faecal coliforms (FC) in the Seine estuary has been developed and coupled with a three-dimensional hydrodynamic model. As input to this model three types of FC sources were considered: (1) FC transported by the Seine river flow at the estuary entrance at Poses dam; (2) FC brought in through the tributaries of the Seine estuary; and (3) the outfalls of the treated effluents of the WWTPs located along the estuary. As previous studies in the Seine estuary showed that a large proportion of FC was attached to SM, two pools of FC were considered separately in the model: free FC and FC attached to SM. Two main processes controlling the fate of FC in the estuary were considered: mortality and settling. The model calculates for a given discharge of the Seine river at Poses the longitudinal distribution of FC along the estuary. The model was validated by comparison of model calculations with experimental data in various hydrological conditions. The model also correctly reproduced the impact of the main river flow rate on the level of estuarine water's contamination. Finally, the model was used to test different scenarios of sanitation, suggesting priorities for sanitation efforts. 相似文献
85.
Previous empirical research indicates that corporate insiders tend to increase (decrease) their shareholdings before events that increase (decrease) firm value. More recent evidence suggests, however, that passage of the Insider Trading Sanctions Act of 1984 (ITSA) may have deterred this behavior. Our results indicate that before passage of the ITSA, insiders exploited their access to nonpublic information by selling shares before the announcement of equity issues. However, after passage of the ITSA insiders no longer displayed this behavior. We conclude the ITSA has a deterrent effect, which is more heavily concentrated on insiders at the highest level of the firm who are most visible to regulators and other market participants. 相似文献
86.
87.
The Determinants of Enterprise Risk Management: Evidence From the Appointment of Chief Risk Officers
Enterprise risk management (ERM) has captured the attention of risk management professionals and academics worldwide. Unlike the traditional "silo-based" approach to corporate risk management, ERM enables firms to benefit from an integrated approach to managing risk that shifts the focus of the risk management function from primarily defensive to increasingly offensive and strategic. Despite the heightened interest in ERM, little empirical research has been conducted on the topic. This study provides an initial attempt at identifying the determinants of ERM adoption. We construct a sample of firms that have signaled their use of ERM by appointing a Chief Risk Officer (CRO) who is charged with the responsibility of implementing and managing the ERM program. We use a logistic regression framework to compare these firms to a size- and industry-matched control sample. While our results suggest a general absence of differences in the financial and ownership characteristics of sample and control firms, we find that firms with greater financial leverage are more likely to appoint a CRO. This finding is consistent with the hypothesis that firms appoint CROs to reduce information asymmetry regarding the firm's current and expected risk profile. 相似文献
88.
Swamy P.A.V.B. Tavlas George S. Lutton Thomas J. 《Journal of Productivity Analysis》2003,20(1):97-114
This paper introduces a simple, yet rich, measure of efficiency changes based on the revenue-generating-ability (RGA) principle. Using this principle, we explain the connections between efficiency changes and the variables, such as pretax profits, interest expense, non-interest expense, profit margins, loan loss provision, and asset quality. These connections are used to explain earnings differences between small and large commercial banks. 相似文献
89.
A tariff system has been set up for the largest wastewater treatment plant in South-East Asia, the Samut Prakarn Wastewater Treatment Plant south of Bangkok, which is currently under completion. Fully functional the plant will have a design capacity for 500,000 m3 per day and will service a combined residential and industrial area with approximately 600,000 residents and 2,300 factories. The tariff system, which includes a tariff model, is based on water consumption and BOD load. As background for setting the tariffs a comprehensive monitoring system including an industrial permitting system has been developed. The paper presents the background and rationale for setting up the system as well as the objective, scope and content of the tariff system and the industrial permit system. Further, the feasibility of introducing cost recovery systems, which is widely accepted in developing economies on the conceptual level and to some extent implemented at the legal and regulatory level, but has yet to be implemented at large, is discussed. 相似文献
90.