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221.
Because work time and its control are unevenly distributed, it shapes opportunities across different groups in society, both reflecting and reinforcing existing forms of inequality. Work time flexibility is seen by many as a way to promote gender equality by increasing the ability of women to exercise some control over their work time, thus facilitating their ability to participate in paid work while maintaining families. Yet, flexibility may take on very different meanings in different contexts, particularly with respect to the degree of control workers have over important aspects of their working time. This paper examines the meaning and distribution of work time flexibility for women in the United States. The paper begins with a brief discussion of the social construction and gendered nature of work time, and the complex and evolving distribution of work time in the United States. Measures of flexibility that seek to capture different aspects of workers' control over work time are then defined and examined through recent data for male and female workers from the General Social Survey (GSS).  相似文献   
222.
America has often been labeled a "throw-away" society due to the large amount of products that could have been reused but are discarded from a typical household on a daily basis. This paper attempts to answer the question of why, when given two consumers with the same income level and socio-economic background, does one consumer choose to replace an older, malfunctioning household product while the other chooses to have the product repaired for further reuse. To help address this question an enhanced replacement model is presented and empirically tested. The replacement model has been around for some time, helping consumers and firms make capital budgeting decisions. This analysis can be extrapolated to the macro level where one economy with a higher societal discount rate might be more strongly characterized as a "throw-away society" than a similar economy with lower societal consumption discount rates.  相似文献   
223.
基于响应时间的供应链协调策略研究   总被引:1,自引:0,他引:1  
高波  石书生 《技术经济》2010,29(6):119-123
在市场需求价格和响应时间敏感下,本文以一个供应商和一个制造商构成的两级MTO供应链为背景,通过建立供应链收益函数模型,分析响应时间对供应链企业决策的影响。给出了供应商和制造商在分散决策下的最优响应策略,得出了供应链双方在分散决策下无法实现供应链完美协调的结论。而后,对供应链协调问题进行了探讨,发现两部收费制契约在满足一定条件下能够实现供应链完美协调,并通过数值实例对上面的结论进行了释义和说明。  相似文献   
224.
国内生产总值(GDP)是制定经济发展战略、规划、年度计划以及各种宏观经济政策的重要依据,研究GDP预测方法具有重要的现实意义。在对鄂尔多斯市GDP数据序列分析的基础上,考虑到BP神经网络可以通过简单非线性函数的复合能够实现对于复杂函数的映射,本文采用BP神经网络方法来预测鄂尔多斯市的GDP,取得了较好的预测效果。  相似文献   
225.
Abstract

Background:

To evaluate the cost burden of patients with advanced Parkinson’s disease (PD) according to the waking hours per day spent in OFF state. An analysis of resource use comprising medical services, professional care and informal care data from an observational, cross-sectional study was conducted.

Methods:

A total of 60 physicians comprising 40 neurologists and 20 geriatricians across the UK participating in the Adelphi PD Disease Specific Programme took part. There were 302 PD patients at H&Y stages 3–5. Patients were characterised according to the percentage of time per day spent in OFF state (<25%, 26–50%, 51–75%, >75%).

Results:

Average 12-monthly total costs increased according to the time spent in OFF state from £25,630 in patients spending less than 25% of their waking hours in OFF to £62,147 for patients spending more than 75% of their time in OFF. Overall, 7% of costs were attributed to direct medical care, while 93% were split between direct non-medical professional care (50%) and indirect informal care (43%).

Limitations:

Low patient numbers in the more advanced disease stages of PD led to very little or no data to directly inform some of the severe health states of the analysis. Data gaps were filled in with data derived from a regression analysis which may affect the robustness of the analysis.

Conclusion:

This study illustrates the increasing costs of advancing PD, in particular related to the time spent in OFF state, and identifies that the foremost cost burden is associated with the care needs of the patient rather than medical services.  相似文献   
226.
This study uses GARCH-EVT-copula and ARMA-GARCH-EVT-copula models to perform out-of-sample forecasts and simulate one-day-ahead returns for ten stock indexes. We construct optimal portfolios based on the global minimum variance (GMV), minimum conditional value-at-risk (Min-CVaR) and certainty equivalence tangency (CET) criteria, and model the dependence structure between stock market returns by employing elliptical (Student-t and Gaussian) and Archimedean (Clayton, Frank and Gumbel) copulas. We analyze the performances of 288 risk modeling portfolio strategies using out-of-sample back-testing. Our main finding is that the CET portfolio, based on ARMA-GARCH-EVT-copula forecasts, outperforms the benchmark portfolio based on historical returns. The regression analyses show that GARCH-EVT forecasting models, which use Gaussian or Student-t copulas, are best at reducing the portfolio risk.  相似文献   
227.
This study conducted a large-scale survey in Dhaka, Bangladesh; the survey involved 95 major hospitals, more than 3000 emergency room patients, and 2 of the largest ambulance operators. Currently, most ambulances are parked within the vicinity of hospitals and are either dispatched or fetched by the acquaintances of the patient on demand, resulting in lengthy round trips. Reducing the response time of ambulances would certainly improve the emergency service, and pre-positioning of the ambulances could be a solution to reducing the response time. This study used two approaches to address the problem. First, the location-allocation problem was solved to find the optimal number of ambulance locations by maximising the demand coverage. Second, separate location-allocation for the peak and off-peaks, using K-means clustering, was applied to systematically optimise the ambulance positioning in small clusters near demand points. These approaches could substantially improve the existing emergency response time. Distributing ambulances near demand points yielded greater improvements in response time than when the ambulances are stationed near hospitals.  相似文献   
228.
229.
今道有信在《关于爱》中探讨了技术关联时代爱的危机和继续存在的可能性;在《关于美》中,就爱与美的关系提出了美是存在的恩惠和爱的命题,将爱置放在了现代性语境中,并赋予它以存在论的意义,但全部讨论没有脱离精神现象学的视野,没有摆脱意识——理念——艺术的范围。美存在于人类生命的根底部,是人类的生存方式和表征;现代社会爱的危机首先是美,即生存本身的危机,因此,对爱的命运的探讨和爱的形而上学的建构只能立足于存在论。  相似文献   
230.
教学环境的优劣对于学生的身心发展有着极为重要的影响。要在正确认识教学环境重要作用的基础上,构建全面优化教学环境的运行机制,关键就是要构建政策支持的领导管理机制,建立传统教学与现代化教学的协调和共享机制,建立全面覆盖的教师培训交流机制,构建多元化的绩效评价机制。  相似文献   
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