全文获取类型
收费全文 | 19342篇 |
免费 | 377篇 |
国内免费 | 1篇 |
专业分类
管理学 | 2810篇 |
民族学 | 70篇 |
人才学 | 1篇 |
人口学 | 1872篇 |
丛书文集 | 76篇 |
教育普及 | 2篇 |
理论方法论 | 1726篇 |
现状及发展 | 1篇 |
综合类 | 260篇 |
社会学 | 9335篇 |
统计学 | 3567篇 |
出版年
2023年 | 106篇 |
2021年 | 124篇 |
2020年 | 291篇 |
2019年 | 381篇 |
2018年 | 445篇 |
2017年 | 604篇 |
2016年 | 476篇 |
2015年 | 349篇 |
2014年 | 462篇 |
2013年 | 2990篇 |
2012年 | 636篇 |
2011年 | 610篇 |
2010年 | 449篇 |
2009年 | 371篇 |
2008年 | 443篇 |
2007年 | 460篇 |
2006年 | 455篇 |
2005年 | 438篇 |
2004年 | 403篇 |
2003年 | 376篇 |
2002年 | 417篇 |
2001年 | 520篇 |
2000年 | 530篇 |
1999年 | 461篇 |
1998年 | 341篇 |
1997年 | 309篇 |
1996年 | 321篇 |
1995年 | 302篇 |
1994年 | 283篇 |
1993年 | 288篇 |
1992年 | 343篇 |
1991年 | 316篇 |
1990年 | 285篇 |
1989年 | 290篇 |
1988年 | 289篇 |
1987年 | 250篇 |
1986年 | 242篇 |
1985年 | 277篇 |
1984年 | 267篇 |
1983年 | 250篇 |
1982年 | 215篇 |
1981年 | 180篇 |
1980年 | 164篇 |
1979年 | 194篇 |
1978年 | 176篇 |
1977年 | 159篇 |
1976年 | 134篇 |
1975年 | 157篇 |
1974年 | 118篇 |
1973年 | 115篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
Cory J. Lindgren 《Risk analysis》2012,32(1):9-15
International and national biosecurity policies consider risk assessment a critical component of overall plant health risk analysis. The Agreement on the Application of Sanitary and Phytosanitary Measures, the International Plant Protection Convention, and the Convention on Biological Diversity all provide guidelines and recommendations on how to use risk assessment. This article discusses how these instruments address risk assessment, and makes recommendations on how the risk assessment process needs to incorporate current geospatial predictive science and geographic information systems into the plant health biosecurity risk analysis toolbox. 相似文献
122.
Chris M. R. Smerecnik Ilse Mesters Math J. J. M. Candel Hein De Vries Nanne K. De Vries 《Risk analysis》2012,32(1):54-66
The role of information processing in understanding people's responses to risk information has recently received substantial attention. One limitation of this research concerns the unavailability of a validated questionnaire of information processing. This article presents two studies in which we describe the development and validation of the Information‐Processing Questionnaire to meet that need. Study 1 describes the development and initial validation of the questionnaire. Participants were randomized to either a systematic processing or a heuristic processing condition after which they completed a manipulation check and the initial 15‐item questionnaire and again two weeks later. The questionnaire was subjected to factor reliability and validity analyses on both measurement times for purposes of cross‐validation of the results. A two‐factor solution was observed representing a systematic processing and a heuristic processing subscale. The resulting scale showed good reliability and validity, with the systematic condition scoring significantly higher on the systematic subscale and the heuristic processing condition significantly higher on the heuristic subscale. Study 2 sought to further validate the questionnaire in a field study. Results of the second study corresponded with those of Study 1 and provided further evidence of the validity of the Information‐Processing Questionnaire. The availability of this information‐processing scale will be a valuable asset for future research and may provide researchers with new research opportunities. 相似文献
123.
A Review of Risk Perceptions and Other Factors that Influence Flood Mitigation Behavior 总被引:1,自引:0,他引:1
In flood risk management, a shift can be observed toward more integrated approaches that increasingly address the role of private households in implementing flood damage mitigation measures. This has resulted in a growing number of studies into the supposed positive relationship between individual flood risk perceptions and mitigation behavior. Our literature review shows, however, that, actually, this relationship is hardly observed in empirical studies. Two arguments are provided as an explanation. First, on the basis of protection motivation theory, a theoretical framework is discussed suggesting that individuals’ high‐risk perceptions need to be accompanied by coping appraisal to result in a protective response. Second, it is pointed out that possible feedback from already‐adopted mitigation measures on risk perceptions has hardly been considered by current studies. In addition, we also provide a review of factors that drive precautionary behavior other than risk perceptions. It is found that factors such as coping appraisal are consistently related to mitigation behavior. We conclude, therefore, that the current focus on risk perceptions as a means to explain and promote private flood mitigation behavior is not supported on either theoretical or empirical grounds. 相似文献
124.
Sankalp Chaturvedi Michael J. Zyphur Richard D. Arvey Bruce J. Avolio Gerry Larsson 《The Leadership Quarterly》2012,23(2):219-232
In this study, we examined the moderating influences of gender and age with respect to testing the heritability of leadership emergence. A large data base of 12,112 twins from Sweden was used in the current study to decompose the variance of emergent leadership into an unobservable genetic component and environmental components that are either common or unshared among twin pairs. Consistent with prior leadership research on genetics, we found that a genetic factor is able to explain a significant proportion of the variation across individuals in predicting how twins perceive their emergent leadership behavior (about 44% for women and 37% for men). Furthermore, we also found that the magnitude of genetic influence on emergent leadership varied with age, but only for women with the heritability estimate being highest for the mid-age women versus lowest for the older women. Implications for advancing research on the genetic and environmental influences on leadership emergence are discussed. 相似文献
125.
K. Michele Kacmar Daniel G. Bachrach Kenneth J. Harris David Noble 《The Leadership Quarterly》2012,23(1):43-54
We develop and test a model that builds directly on social exchange theory to predict different roles for supervisor trust in the relationships between organizational citizenship behavior and relationship conflict occurring between supervisors and subordinates and between peers. Specifically, we posit that the association between citizenship behavior and relationship conflict between employees and supervisors is mediated by supervisor trust, while the association between citizenship behaviors and relationship conflict occurring between peers is moderated by supervisor trust. We test our dual role for supervisor trust in a field study of 160 supervisor–employee dyads. Results support the different roles played by supervisor trust. We close by discussing the implications of our results for theory and practice in the relationship conflict and citizenship domains. 相似文献
126.
We examined the validity of three leadership approaches in an organization in India. We used a multi-theory and multi-method design to competitively test transformational leadership theory, the nurturant–task leadership model, and a local organization-specific leadership model. Transformation leadership theory is one of the most widely studied and accepted theories in Western countries and is viewed as a universalistic leadership approach. The nurturant–task leadership model was developed in India and viewed as a culture-specific leadership approach. We also developed a local leadership model, called RDO, a pseudonym for the organization, and viewed it as an organization-specific leadership approach, using a qualitative analysis of interview data. The overall results of our qualitative–quantitative work provide strong support for the RDO leadership model, some support for a nurturant–task leadership model, and minimal support for transformational leadership theory. These results suggest that research designs that include a multi-theory, multi-methods approach in a single culture have the potential to increase our understanding of leadership processes. 相似文献
127.
In a service environment a service provider needs to determine the amount and kinds of capacity to meet customers’ needs over many periods. To make good decisions, she needs to know the probability distribution of her customers’ demand in each period. We study a situation in which customers’ demand for a given service is random in each period, but inelastic, or modeled well by this assumption, and cannot be delayed to the next period. This article presents a mechanism that allows a service provider to learn the distribution of a customer's demand by offering him a set of contracts through which he can partially prepay for future service for a reduced cost for units of service based on anticipated needs. We describe the form of a set of contracts that will cause the customer to reveal his demand distribution as he minimizes his expected costs. To justify the effort of organizing and offering contracts, we present an application that demonstrates the cost savings to the service provider with better capacity planning using the truthfully elicited distribution. 相似文献
128.
We compare earnings inequality and mobility across the United States, Canada, France, Germany and the United Kingdom during the late 1990s. A flexible model of earnings dynamics that isolates positional mobility within a stable earnings distribution is estimated. Earnings trajectories are then simulated, and lifetime annuity value distributions are constructed. Earnings mobility and employment risk are found to be positively correlated with base‐year inequality. Taken together they produce more equalization in countries with high cross‐section inequality such that the countries in our sample have more similar lifetime inequality levels than cross‐section measures suggest. 相似文献
129.
Vivek Ramamurthy J. George Shanthikumar Zuo‐Jun Max Shen 《Production and Operations Management》2012,21(2):291-308
In this paper, we consider data‐driven approaches to the problem of inventory control. We first consider the approach of operational statistics and review related results which enable us to maximize a priori expected profit uniformly over all parameter values, when the demand distribution is known up to the location and scale parameters. For the case of the unknown shape parameter, we first suggest a heuristic approach based on operational statistics to obtain improved ordering policies and illustrate the same for the case of a Pareto demand distribution. In more general cases where the heuristic is not applicable, we suggest linear correction and support vector regression approaches to better estimate ordering policies, and illustrate these using a Gamma demand distribution. In certain cases, our proposed approaches are found to yield significant improvements. 相似文献
130.
Sascha Kraus J. P. Coen Rigtering Mathew Hughes Vincent Hosman 《Review of Managerial Science》2012,6(2):161-182
Entrepreneurial Orientation (EO) is often mentioned as an antecedent of growth, competitive advantage and superior performance,
and prior empirical research has often shown a positive relationship between EO and performance appears to exist. However,
an important question that remains unanswered is what effect EO might have on firm performance during periods of economic
crisis, and the severe environmental turbulence that accompany such crises. This research is a first investigation towards
the effects of EO on the performance of small and medium sized firms during the current global economic crisis. In this study
we use the multidimensional model of EO and test a series of hypotheses pertaining to its performance effects using survey
data gathered from 164 Dutch SMEs. The present research shows that proactive firm behavior positively contributes to SME performance
during the economic crisis. We further show that innovative SMEs do perform better in turbulent environments, but those innovative
SMEs should minimize the level of risk and should take action to avoid projects that are too risky. 相似文献