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971.
在认知无线电网络中,图论与量子遗传算法相结合的频谱分配策略能够提高频谱利用率,但存在早熟和收敛精度不够等缺点。为了解决该问题而实现算法的优化,对图着色理论的频谱分配模型进行数学建模,并针对该模型提出了改进的量子遗传算法。首先,通过使用小生境技术初始化种群,使种群分布更加广泛、算法的收敛度更高;其次,根据进化代数对量子旋转角进行实时动态调整,对染色体进行阈值变异,防止个体陷入早熟,跳出局部解;然后,对干扰约束条件进行重新设计,有效地避免盲目性,提高了网络的公平性和网络效益。仿真结果表明,所提算法有效地提高了频谱利用率,极大地增强了网络系统的性能。  相似文献   
972.
受海况、浸水、结冰、对星等因素影响,飞行员海上遇险后报位可靠性较低,工作时长较短。为此,提出一种自适应功率退避方法,在对报位影响因素分析基础上,利用深度神经网络,通过对经纬度、高度、俯仰角、方向、加速度、速度、浸水、信号、电量等多维度数据进行学习,拟合出覆冰、浪涌、液面等信号特征与环境特征联想模型,自适应控制信号发射时机,实现功耗的有效控制。试验表明,该方法将通信成功率及工作时长分别由36.3%、6.0 h提升至73.3%、8.6 h。  相似文献   
973.
ABSTRACT

The food and beverage sector of the hospitality industry is known for being an emotionally labor-intensive environment. The events that transpire over the course of a shift lead to various emotions, which ultimately dictate the behaviors of the employees working in this industry. Of particular interest to this study was the interplay between environmental antecedents (power and distributive justice) and their influence on a negative emotion (anger) and a positive emotion (affective organizational commitment). Additionally, this study sought to understand how anger and affective organizational commitment influenced positive (organizational citizenship behavior) and negative (counterproductive work behavior) workplace behaviors using the lens of the affective events theory. The results of this study revealed that anger had the strongest effect on counterproductive work behavior and that all of the relationships were significant except from anger to affective organizational commitment and affective organizational commitment to counterproductive work behavior.  相似文献   
974.
Korea’s financial system used to be bank-based, with banks playing the leading role in financing corporations. As highlighted by Park et al. (2019), however, bond markets have developed rapidly in Korea and other Asian countries. The corporate bond market competes with banks as a source of finance for large borrowers. As such, bond markets may affect banking sector operation, a process known as disintermediation. In this paper, we examine whether bond market development improves the efficiency of resource allocation in Korean bank lending. We propose two channels through which bond market development affects the efficiency of bank lending. Since the two channels have opposing effects on the efficiency of banking, the issue must be settled by empirical analysis. We find that bank loans are much less efficient than bond financing in allocating resources across industries. Furthermore, banks are particularly inefficient in resource allocation in industries that rely more on bond financing. This suggests that competition from bond financing does not improve allocative efficiency of bank loans.  相似文献   
975.
Wind turbine construction, governed by complex multi-scale governance systems, can cause conflict between actors interested in forest management. We examined wind turbine conflicts in forests in two case studies, the state of Maine, USA and the state of Rhineland-Palatinate, Germany. Specifically, we examined based on triangulation of documents, participant observation, and qualitative interviews with 46 actors how actors argued in favor of certain scales within the wind turbine multi-scale governance systems and how they applied scalar strategies within them. In this paper, we propose a typology that describes actor behavior within multi-scale governance systems. Seven different actor types within multi-scale governance were identified: the Knowledge Exchanger, the Linker, the Creator, the Maintainer, the Power Shifter, the Mobile Learner, and the Overwhelmed & Passive. Actors involved in wind turbine conflicts within forests re-shaped and re-defined the governance system by their actions in the conflict process. However, not all actors could equally participate in scalar strategies. Therefore, only some actors had advantages in re-shaping the governance system according to their interests.  相似文献   
976.
This paper models a resource allocation problem in the political context. Voters and political candidates of two parties are positioned in each of n given electoral districts. We assume that each voter will vote for the candidate he is more attracted to. This attraction is modeled by an attraction function. Each of the parties now attempts to allocate a finite budget to maximize their objective, which is either the popular vote or the number of districts, in which the party has a majority. Individual scenarios are examined with respect to leader-follower solutions and Nash equilibria. The paper then describes a dynamic model that successively allocates existing funds plus additional donations to candidates in different electoral districts.  相似文献   
977.
微时代是以微博、微信等社交平台为代表的新时代。高职院校教育主体与受教育主体面对社交平台的新型话语体系,展现出不同的话语特征。教育主体只有进行话语权的体系建构,才能帮助学生形成正确认知、树立正确的价值观念,真正培养具有坚定信念和国际视野的高端技术技能人才。  相似文献   
978.
Although the literature underlines the importance of finance in international trade, no prior study has examined the causal links between market power in banking and export performance. Using a world sample over the 1997-2010 period, and accounting for both observed and unobserved country heterogeneity, we find a positive effect of bank market power on exports, especially in high-income countries. We also document that this export-enhancing effect is more potent in informationally opaque markets. Our findings accord with information hypothesis which suggests that market power in banking induces stronger bank-firm relationships which can generate benefits for both borrowers and lenders. Policy interventions should, therefore, promote the supply of relationship lending as a means to mitigate informational asymmetries in the export market.  相似文献   
979.
杜朝运  汪丽瑾 《征信》2020,38(2):69-76
运用中国家庭金融调查(CHFS)数据,研究社会互动与家庭金融资产配置之间的关系。研究发现,适当增强社会互动会促进家庭更多地参与风险金融市场,增加投资风险资产的比例,提高金融资产的分散化程度,优化资产的配置效率。但当社会互动达到一定程度后,过度的社会互动则会抑制家庭参与风险市场,减少风险资产的投资比重,降低金融资产的分散化程度以及资产配置的有效性。因此,家庭需要建立适度而高质量的社会互动,这有助于家庭获得更多的外部资源,缓解信息不对称,降低交易成本,从而优化家庭金融资产配置。  相似文献   
980.
Our inquiry advances a comparison of the anthropological content of Thorstein Veblen’s evolutionary perspective with the foundations of the political anthropology drawn from selected works of Pierre Clastres. We seek to establish that what can be referred to as a clastrean reference can simultaneously offer new perspectives on institutionalism, while maintaining a radical and emancipatory understanding of Veblen’s writings. In this sense, we seek to reconsider and reevaluate the role of economic surplus drawn from Veblen’s anthropology, while also offering a general and critical perspective for understanding the emergence of coercive power within societies.  相似文献   
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