全文获取类型
收费全文 | 19314篇 |
免费 | 509篇 |
国内免费 | 1篇 |
专业分类
管理学 | 2704篇 |
民族学 | 92篇 |
人才学 | 1篇 |
人口学 | 2005篇 |
丛书文集 | 99篇 |
教育普及 | 1篇 |
理论方法论 | 1731篇 |
现状及发展 | 1篇 |
综合类 | 225篇 |
社会学 | 9391篇 |
统计学 | 3574篇 |
出版年
2023年 | 117篇 |
2021年 | 98篇 |
2020年 | 268篇 |
2019年 | 384篇 |
2018年 | 459篇 |
2017年 | 644篇 |
2016年 | 500篇 |
2015年 | 328篇 |
2014年 | 423篇 |
2013年 | 3376篇 |
2012年 | 638篇 |
2011年 | 559篇 |
2010年 | 423篇 |
2009年 | 412篇 |
2008年 | 454篇 |
2007年 | 439篇 |
2006年 | 453篇 |
2005年 | 429篇 |
2004年 | 417篇 |
2003年 | 377篇 |
2002年 | 433篇 |
2001年 | 464篇 |
2000年 | 459篇 |
1999年 | 449篇 |
1998年 | 336篇 |
1997年 | 314篇 |
1996年 | 304篇 |
1995年 | 284篇 |
1994年 | 254篇 |
1993年 | 268篇 |
1992年 | 292篇 |
1991年 | 285篇 |
1990年 | 291篇 |
1989年 | 317篇 |
1988年 | 243篇 |
1987年 | 245篇 |
1986年 | 235篇 |
1985年 | 289篇 |
1984年 | 264篇 |
1983年 | 256篇 |
1982年 | 207篇 |
1981年 | 184篇 |
1980年 | 182篇 |
1979年 | 221篇 |
1978年 | 172篇 |
1977年 | 153篇 |
1976年 | 154篇 |
1975年 | 140篇 |
1974年 | 139篇 |
1973年 | 117篇 |
排序方式: 共有10000条查询结果,搜索用时 578 毫秒
1.
Dennis Wagenaar Tiaravanni Hermawan Marc J. C. van den Homberg Jeroen C. J. H. Aerts Heidi Kreibich Hans de Moel Laurens M. Bouwer 《Risk analysis》2021,41(1):37-55
Damage models for natural hazards are used for decision making on reducing and transferring risk. The damage estimates from these models depend on many variables and their complex sometimes nonlinear relationships with the damage. In recent years, data‐driven modeling techniques have been used to capture those relationships. The available data to build such models are often limited. Therefore, in practice it is usually necessary to transfer models to a different context. In this article, we show that this implies the samples used to build the model are often not fully representative for the situation where they need to be applied on, which leads to a “sample selection bias.” In this article, we enhance data‐driven damage models by applying methods, not previously applied to damage modeling, to correct for this bias before the machine learning (ML) models are trained. We demonstrate this with case studies on flooding in Europe, and typhoon wind damage in the Philippines. Two sample selection bias correction methods from the ML literature are applied and one of these methods is also adjusted to our problem. These three methods are combined with stochastic generation of synthetic damage data. We demonstrate that for both case studies, the sample selection bias correction techniques reduce model errors, especially for the mean bias error this reduction can be larger than 30%. The novel combination with stochastic data generation seems to enhance these techniques. This shows that sample selection bias correction methods are beneficial for damage model transfer. 相似文献
2.
Allan B. I. Bernardo Mary Angeline A. Daganzo Anna Carmella G. Ocampo 《Social indicators research》2018,139(1):277-292
Abusive supervision in the workplace has been shown to have important direct consequence in work and work relationship, and also indirect consequences to workers’ well-being and relationships outside work. Consequences of abusive supervision have not been studied among migrant workers whose status in the host country of work is dependent on maintaining the work contract. This study investigates abusive supervision in 247 Filipino migrant workers in Macau, who hold temporary work contracts and work visas to engage in various low-skilled work (e.g., domestic helper, security guard, etc.). The study tests a model representing the indirect consequences of abusive supervision on the self-esteem and acculturation orientation of migrant workers, in particular, on the tendency to reject their heritage culture in their attempt to acculturate in the host country. Mediation analysis indicated that abusive supervisory perceptions led to lower self-esteem (b = ?.19), which in turn relates to tendency to reject their heritage culture as part of acculturation (b = ?.45) [indirect effect = .08, 90 % CI .04, .15]. The rejection of heritage culture is interpreted as a coping response to the negative indirect consequences of abusive supervision perceptions that may be partly attributed to being a migrant Filipino worker. The results are discussed in terms of how the acculturation of migrant workers reflects aspects of their well-being that may be adversely affected by vocational-related stress in the host country. 相似文献
3.
4.
Has Opposition to Immigration Increased in the United States after the Economic Crisis? An Experimental Approach 下载免费PDF全文
Mathew J. Creighton Amaney Jamal Natalia C. Malancu 《The International migration review》2015,49(3):727-756
We employ two population‐level experiments to accurately measure opposition to immigration before and after the economic crisis of 2008. Our design explicitly addresses social desirability bias, which is the tendency to give responses that are seen favorably by others and can lead to substantial underreporting of opposition to immigration. We find that overt opposition to immigration, expressed as support for a closed border, increases slightly after the crisis. However, once we account for social desirability bias, no significant increase remains. We conclude that the observed increase in anti‐immigration sentiment in the post‐crisis United States is attributable to greater expression of opposition rather than any underlying change in attitudes. 相似文献
5.
Cancho Vicente G. Macera Márcia A. C. Suzuki Adriano K. Louzada Francisco Zavaleta Katherine E. C. 《Lifetime data analysis》2020,26(2):221-244
Lifetime Data Analysis - Frailty models are generally used to model heterogeneity between the individuals. The distribution of the frailty variable is often assumed to be continuous. However, there... 相似文献
6.
Alex B. Anderson 《Journal of sex research》2015,52(3):317-326
Distraction from erotic cues during sexual encounters is a major contributor to sexual difficulties in men and women. Being able to assess distraction in studies of sexual arousal will help clarify underlying contributions to sexual problems. The current study aimed to identify the most accurate assessment of distraction from erotic cues in healthy men (n = 29) and women (n = 38). Participants were assigned to a no distraction, low distraction, or high distraction condition. Distraction was induced using an auditory distraction task presented during the viewing of an erotic video. Attention to erotic cues was assessed using three methods: a written quiz, a visual quiz, and a self-reported distraction measure. Genital and psychological sexual responses were also measured. Self-reported distraction and written quiz scores most accurately represented the level of distraction present, while self-reported distraction also corresponded with a decrease in genital arousal. Findings support the usefulness of self-report measures in conjunction with a brief quiz on the erotic material as the most accurate and sensitive ways to simply measure experimentally-induced distraction. Insight into distraction assessment techniques will enable evaluation of naturally occurring distraction in patients suffering from sexual problems. 相似文献
7.
8.
9.
Robert C. Cope Joshua V. Ross Talia A. Wittmann Michael J. Watts Phillip Cassey 《Risk analysis》2019,39(1):35-53
Understanding the risk of biological invasions associated with particular transport pathways and source regions is critical for implementing effective biosecurity management. This may require both a model for physical connectedness between regions, and a measure of environmental similarity, so as to quantify the potential for a species to be transported from a given region and to survive at a destination region. We present an analysis of integrated biosecurity risk into Australia, based on flights and shipping data from each global geopolitical region, and an adaptation of the “range bagging” method to determine environmental matching between regions. Here, we describe global patterns of environmental matching and highlight those regions with many physical connections. We classify patterns of global invasion risk (high to low) into Australian states and territories. We validate our analysis by comparison with global presence data for 844 phytophagous insect pest species, and produce a list of high‐risk species not previously known to be present in Australia. We determined that, of the insect pest species used for validation, the species most likely to be present in Australia were those also present in geopolitical regions with high transport connectivity to Australia, and those regions that were geographically close, and had similar environments. 相似文献
10.
Ce Shen Jessica Johnson Zhenhe Chi John B. Williamson 《International social security review》2020,73(2):3-26
China’s pension reform during the past three decades has allowed a majority of China’s population to be covered by a pension scheme. Of particular note has been the New Rural Pension Scheme (NRPS), a voluntary programme introduced starting in 2009. One goal of our analysis is to assess that pension scheme, using a variety of sources of information including data drawn from recent (2013 and 2015) nationwide China Health and Retirement Longitudinal Surveys (CHARLS). Our analysis involves an exploration of differences between the generosity and structure of the NRPS and other pension schemes currently in place. We also explore the feasibility of reforming the current “quasi-social pension” component of the NRPS by substituting a universal non-contributory social pension pillar. In connection with our assessment of the NRPS, we note the unusually low benefit levels for rural China. 相似文献