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11.
苏南乡村地区一直是中国乡村建设的先行区域,特殊的纵横交错的水网结构构成了一个错综复杂的系统,呈现出其他地区不具有的复杂性和生态特殊性。随着城镇的扩张,乡村的发展建设使其水网空间的平衡发展面临极大的挑战。传统单一静态的规划方法逐渐显示出无法适应经济、社会等发展要求的缺陷。苏南乡村地区以水为核心,从水生态系统服务供需关系的视角下探究水网乡村的适应性规划策略更加适应当前的乡村现状和需求。以传统水网乡村空间形态转译为基础,建立水生态系统供需服务评估体系,在评估水生态系统服务供需能力的基础上,分析供需分异模式及供需矛盾。从构建乡村水域空间生态格局、乡村水域空间功能分区规划,以及乡村水域空间多情景预判3个方面,提出苏南水网乡村的适应性规划策略,并为水网乡村的生态实践提出新思路。  相似文献   
12.
文章运用Logistic回归模型,基于武汉市调研数据,从实践角度透视和思考公民参与网络反腐的意愿及影响因素。研究发现,大部分接受调研公民参与网络反腐的意愿较高;政府信任对公民参与网络反腐意愿的负向影响非常显著;年龄的负向影响比较显著;月收入的正向影响一般显著;性别、受教育程度和单位类别对其参与意愿的影响不显著。  相似文献   
13.
The increase in interconnectivity and developments in technology have caused cyber security to become a universal concern. This paper highlights the dangers of the evolution of cyber risk, the challenges of quantifying the impact of cyber-attacks and the feasibility of the traditional actuarial methodologies for quantifying cyber losses. In this paper, we present a practical roadmap for assessing cyber risk, a roadmap that emphasizes the importance of developing a company and culture-specific risk and resilience model. We develop a structure for a Bayesian network to model the financial loss as a function of the key drivers of risk and resilience. We use qualitative scorecard assessment to determine the level of cyber risk exposure and evaluate the effectiveness of resilience efforts in the organization. We highlight the importance of capitalizing on the knowledge of experts within the organization and discuss methods for aggregating multiple assessments. From an enterprise risk management perspective, impact on value should be the primary concern of managers. This paper uses a value-centric/reputational approach to risk management rather than a regulatory/capital-centric approach to risk.  相似文献   
14.
This paper employs network analysis to study world trade from 1995 to 2014. We focus on the main connective features of the world trade network (WTN) and their dynamics. Results suggest that countries’ efforts to attain the benefits of trade have resulted in an intertwined network that is increasingly dense, reciprocal, and clustered. However, these features do not correspond to a linear aggregation of the characteristics of its constituents (trade sectors). Trade linkages are distributed homogeneously among countries, but their intensity (i.e. their value) is highly concentrated in a small set of countries. The main connective features of the WTN were not affected by the 2007–2008 international financial crisis. However, we find that the crisis marks a turning point in the evolution of the WTN from a two-group (led by the US and Germany) to a three-group (led by the US, Germany, and China) hierarchical structure.  相似文献   
15.
Cancellations are a key aspect of hotel revenue management because of their impact on room reservation systems. In fact, very little is known about the reasons that lead customers to cancel, or how it can be avoided. The aim of this paper is to propose a means of enabling the forecasting of hotel booking cancellations using only 13 independent variables, a reduced number in comparison with related research in the area, which in addition coincide with those that are most often requested by customers when they place a reservation. For this matter, machine-learning techniques, among other artificial neural networks optimised with genetic algorithms were applied achieving a cancellation rate of up to 98%. The proposed methodology allows us not only to know about cancellation rates, but also to identify which customer is likely to cancel. This approach would mean organisations could strengthen their action protocols regarding tourist arrivals.  相似文献   
16.
This paper employs a Russell multi-activity network DEA model and divides the overall innovation process into the upstream Research and Development (R&D) process and the downstream commercialization process to appraise the innovation performance of China's high-tech industries from 2009 to 2013. This model can deal with the problems of intermediates, shared inputs and slack-based measure in a unified framework, and the result can provide policy makers with process-specific information on how to improve the innovation performance of China's high-tech industries. The main findings are presented as follows. First, the overall efficiency of China's high-tech industries still remains at a low level, which has its roots mainly in commercialization inefficiencies other than R&D inefficiencies. Second, for most provinces, their R&D efficiencies do not match up with their commercialization efficiencies. Finally, the innovative activities of China's high-tech industries should be driven by the market demand -oriented for the improvement of innovation efficiency.  相似文献   
17.
This paper endogenizes the number of firms in an industry with positive network effects, complete incompatibility, and firms that compete in quantity. To this end, we compare two possibilities: free entry and second‐best number of firms (the one that maximizes social welfare). We show that with business‐stealing competition, free entry yields, in general, more firms than the socially optimal solution. In addition, we find that by the nature of the industry with firm‐specific networks, total production may be greater or lower under free entry than with a regulator; moreover, some industries attain their maximum social welfare with a monopoly.  相似文献   
18.
区别于现有研究通常将跨国并购视为一个“事件”研究其对并购企业技术创新的影响,基于创新网络视角,文章采用中国上市公司数据,通过关系嵌入和结构嵌入两个维度探讨基于跨国并购的国外创新网络对创新质量的影响机制。研究发现,通过跨国并购嵌入创新网络的直接联系促进了创新质量提升,间接联系和结构洞对创新质量产生了显著的抑制效应。网络异质性对基于跨国并购的创新网络嵌入与创新质量具有倒U型调节作用,在网络异质适度阶段,网络异质性正向调节基于跨国并购的创新网络嵌入的创新质量效应,在网络异质过度阶段,网络异质性具有负向调节效应。研究发现为新兴经济体企业实施跨国并购,有效嵌入国外创新网络,配置创新资源,提升创新质量,提供了有价值的参考。  相似文献   
19.
UxDMA算法是一种高效的集中式算法,是用于时分多址、频分多址和码分多址信道分配的统一算法。在UxDMA的基础上,利用多波束天线的多波束形成能力,针对低时延定向ad hoc网络提出了一种集中式调度算法——CLSM(Centralized Low-delay Scheduling Algorithm Based on Multi-beam Antennas)。CLSM通过不同时延等级限制的报文来比较着色后发送链路的优先级,优先选择高优先级链路传输。通过仿真验证了CLSM的性能:与UxDMA相比,该算法在多时延限制的发送端调度中表现出了更好的吞吐量和时延性能。  相似文献   
20.
基于2013年和2020年29个省的数据,用因子模型测算各省数字经济发展水平,在此基础上使用修正引力模型构建数字经济空间关联网络,并深入分析此网络特征。结果表明:中国数字经济发展水平存在差异,东部地区高于中西部地区;中国数字经济空间关联网络密度不断增大;北京、山东、江苏一直是网络的重要输出省份,近年来西部地区在网络中的作用越来越明显;地理位置相邻、贸易开放度和产业结构对网络的形成有显著影响。  相似文献   
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