首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   5214篇
  免费   131篇
  国内免费   1篇
财政金融   903篇
工业经济   360篇
计划管理   808篇
经济学   1121篇
综合类   67篇
运输经济   30篇
旅游经济   64篇
贸易经济   797篇
农业经济   238篇
经济概况   955篇
邮电经济   3篇
  2023年   32篇
  2020年   68篇
  2019年   107篇
  2018年   128篇
  2017年   132篇
  2016年   126篇
  2015年   69篇
  2014年   128篇
  2013年   506篇
  2012年   157篇
  2011年   194篇
  2010年   160篇
  2009年   151篇
  2008年   148篇
  2007年   138篇
  2006年   117篇
  2005年   92篇
  2004年   96篇
  2003年   92篇
  2002年   87篇
  2001年   117篇
  2000年   108篇
  1999年   85篇
  1998年   102篇
  1997年   77篇
  1996年   73篇
  1995年   92篇
  1994年   57篇
  1993年   84篇
  1992年   76篇
  1991年   80篇
  1990年   74篇
  1989年   78篇
  1988年   66篇
  1987年   73篇
  1986年   77篇
  1985年   83篇
  1984年   90篇
  1983年   64篇
  1982年   73篇
  1981年   66篇
  1980年   78篇
  1979年   66篇
  1978年   47篇
  1977年   50篇
  1976年   39篇
  1975年   49篇
  1974年   34篇
  1973年   39篇
  1972年   33篇
排序方式: 共有5346条查询结果,搜索用时 62 毫秒
991.
浅谈物流管理专业的实践教学   总被引:1,自引:0,他引:1  
1 引言 物流管理是一门实践性很强的学科.物流管理专业为适应社会主义市场经济的需要,培养掌握扎实的现代物流管理基本理论和专门知识,能在生产、流通和服务领域中面向生产一线的操作层、管理层的高素质技能型人才.国家教育行政主管部门把物流专业人才列为全国十二类技能型紧缺人才之一.我国的物流教育也随着物流产业的蓬勃发展在不断的改革和创新,物流管理专业的实践教学已成为我国物流教育新的起跑点.  相似文献   
992.
We offer empirical information on the correlates of commercialization activity for research projects funded through the US National Institutes of Health's (NIH's) Small Business Innovation Research (SBIR) award program. Based on this analysis we suggest possible recommendations for improving this aspect of the performance of NIH's SBIR program. Specifically, we estimate a model of the probability of commercialization as a function of the project's ability to attract additional developmental funding, along with other control variables. We find that additional developmental funding from non-SBIR federal sources and from own internal sources are important predictors of commercialization success, relatively more so than additional developmental funding from venture capitalists. We also find, among other things, that university involvement in the underlying research increases the probability of commercialization. Thus, these factors should be considered by NIH when making awards, if increased commercialization is an objective.  相似文献   
993.
Abstract

Background: Private health insurance (PHI) represents the largest source of insurance for Americans. Hispanic Americans have one of the lowest rates of PHI coverage. The largest group in the US Hispanic population are Mexican Americans; they account for about two in every three Hispanics. One in every three Mexican Americans aged 64 years and under did not have health insurance coverage. Mexican Americans have the most unfavorable health insurance coverage of any population group in the nation.

Objectives: The objective is to determine the factors associated with the gap in PHI coverage between Mexican American and non-Hispanic American men.

Methods: This study used the National Health Interview Surveys (2010–2013) as the sample. A non-linear Oaxaca-Blinder decomposition was run, estimating the explained and unexplained gap in PHI coverage between the groups. Several robustness tests of the model were also included.

Results: This study estimates that 44.4% of employed Mexican American men are covered by PHI compared to 79.5% of non-Hispanic American men. Nearly 60% of employed Mexican American men were found to be foreign born, 35% have an educational attainment less than a high school degree, and 40% are likely to have language barriers. Decomposition results show that income, low educational attainment, being foreign-born, and language barriers diminished the probability of private health insurance coverage for Mexican Americans, and that 10% of the gap is unexplained.

Conclusions: Most of the difference in the PHI rate between Mexican American men and non-Hispanic men is explained by observable differences in group characteristics: education, language, and immigration status. About 10% of the difference can be attributed to discrimination under the traditional interpretation of an Oaxaca-Blinder decomposition. The PHI rate gap is large and persistent for Mexican American men.  相似文献   
994.
The existence of long-run relationships among the ASEAN-5 equity markets is empirically investigated. This study utilized weekly data spanning January 1988 to August 1999. The results of Granger noncausality test due to Toda and Yamamoto (Journal of Econometrics,66, 225–50, 1995) reveal that the Singapore equity market was not affected by other markets except by the Philippines in the long run. This result shows that there exist opportunities for beneficial international portfolio diversification within the context of the Asean-5 equity markets.  相似文献   
995.
As cultural, social, political and economic changes take place, the secondary or high school curriculum should reflect and respond to changing needs and aspirations of students. Technology Education has been proactive in this arena as it has transformed over the decades to meet ever-changing societal needs. The most recent change to the discipline has been to add engineering and, as a result, adopting a new name and curriculum-Engineering and Technology Education. The added component and name change in Technology Education is causing discussions about what the new direction means, what professional preparation changes will be incurred, and what work graduating students will be prepared to do. In light of these changes, this study investigated perceptions of high school students in the United States of America about engineering and technology courses they take. To investigate whether students’ perceptions are in accord with current changes in Engineering and Technology Education, 316 students enrolled in engineering and technology courses in Georgia schools that have an affiliation with the Georgia Engineering and Technology Education Association (GETEA) were surveyed. According to data analyses, students’ perceptions can be divided into two factors. Educational Value of Course (factor 1) was extracted from statements measuring the degree to which the courses prepare students for employment and provide them with information regarding future employment. Personal Relevance of Course (factor 2) was derived from statements measuring students’ perceptions about links between engineering and technology education and their personal lives. Such findings suggest these students valued their engineering and technology courses, planned to continue their education, made good grades, and had varied types of career expectations for jobs such as design engineers and architects.  相似文献   
996.
The Carpathian Basin is one of the most vulnerable European regions in terms of potential climate change impacts on biodiversity. Its wide range of tourism activities make it uniquely suitable for assessing the effects of climate change on tourism. This research sought to create a Tourism Adaptation Portfolio (TAP) for the Szentendre micro-region in Hungary and to assemble an adaptation toolbox for current and future use by tourism organizations. The TAP contains practical, easy to implement solutions for key stakeholders in the sector by adaptation type (technology, management, behavior, education, policy). Surveys of local tourism suppliers showed that 70% said they were well informed, largely by the Internet, but 55% admitted to not knowing enough. The methodology outlined here is transferable and the process can be replicated elsewhere, supporting other regions in becoming climate-friendly tourism destinations, creating opportunities for uniquely positioning a region for consumers. The article provides a concise overview of tourism provider attitudes assessed through a questionnaire, shedding light on points of intervention, willingness to pay, main barriers and suitable adaptation instruments. The adaptive capacity of stakeholders is also discussed, which is indispensable for implementing successful practices in adaptation and maintaining the current level of environmental services.  相似文献   
997.
Flood risk insurance can be an effective tool in assisting the restoration of damaged property after a flood event and sustaining communities through difficult times. It can also form part of a wider flood risk management strategy. In the light of recent flood events in the UK and in the context of changing property insurance markets, the universal cover previously enjoyed by floodplain residents has been called into question. Conflicting media and industry views leave the floodplain resident and the wider community in confusion. A survey of floodplain residents in England regarding their experience with flooding and flood insurance in England has been undertaken. The results reveal that some floodplain residents do indeed encounter difficulties when seeking insurance for their homes. However, despite the risk‐averse policies of some insurers, availability of insurance is still strong in both at‐risk and previously flooded locations. Success in gaining insurance may lead to complacency among residents who see no advantage in pursuing other, more costly, damage mitigation actions. As a tool in risk management, therefore, the market is prevented from realising its potential by competition, which results in a lack of a consistent approach, rewards homeowners' search strategies and reduces information flow.  相似文献   
998.
This study demonstrates the effects of framing safety precautions on the presentation of a controversial product (recycled water [RW]) to the inhabitants of two Greek towns by asking them whether they would visit various configurations of a public park irrigated with RW. The same questions are posed in an additional version augmented with a safety alert. Among many others, results mainly show that willingness to visit (WTV) a park irrigated with RW or willingness to pay for RW decrease when respondents are confronted with the safety statement that ‘the irrigated parts are isolated and have been properly marked for the visitor so that he/she does not come into touch with RW’. Moreover, WTV does not decrease when there is previous experience with the park. The upgrade of RW from secondary to tertiary treatment is valuated only when safety alerts are present. The paper yields promotion insights useful for relevant utilities, organizations, and governments which are interested in forming a social marketing mix for this product while contributing to the theoretical and empirical understanding of framing effects with their experimental demonstration in the two case studies.  相似文献   
999.
Allocating resources to competing large‐scale infrastructure projects involves multiple objectives. Traditional decision‐aiding methodologies focus on the trade‐offs among performance and resource objectives. Existing methodologies may fail to account for unknown and emergent risks that are typical of large‐scale infrastructure investment allocation problems. In modern portfolio theory, it is well known that a diversified portfolio can be very effective to reduce non‐systematic risks. The approach of diversification is equally important in choosing robust portfolios of infrastructure projects that may be subject to emergent and unknown risks. In this paper, we demonstrate a methodology to analyze and compare the diversification of portfolios of large‐scale infrastructure projects. We classify and explore several metrics of diversification and integrate them with risk and other performance objectives in a multiobjective approach. We test the new metrics and the methodology in a case study of hundreds of millions of dollars of infrastructure investments. The results suggest that the solutions that consider diversification are more robust to emergent risks, thus, identifying an opportunity to incorporate diversification‐based optimization methodologies to support a variety of problems involving large‐scale infrastructure investments.  相似文献   
1000.
In this work we propose Monte Carlo simulation models for dynamically computing MaxVaR for a financial return series. This dynamic MaxVaR takes into account the time-varying volatility as well as non-normality of returns or innovations. We apply this methodology to five stock market indices. To validate the proposed methods we compute the number of MaxVaR violations and compare them with the expected number. We also compute the MaxVaR-to-VaR ratio and find that, on average, dynamic MaxVaR exceeds dynamic VaR by 5–7% at the 1% significance level, and by 12–14% at the 5% significance level for the selected indices.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号