全文获取类型
收费全文 | 3249篇 |
免费 | 102篇 |
国内免费 | 1篇 |
专业分类
管理学 | 463篇 |
民族学 | 11篇 |
人才学 | 1篇 |
人口学 | 276篇 |
丛书文集 | 22篇 |
理论方法论 | 358篇 |
综合类 | 42篇 |
社会学 | 1353篇 |
统计学 | 826篇 |
出版年
2023年 | 17篇 |
2021年 | 20篇 |
2020年 | 62篇 |
2019年 | 77篇 |
2018年 | 108篇 |
2017年 | 116篇 |
2016年 | 77篇 |
2015年 | 76篇 |
2014年 | 93篇 |
2013年 | 663篇 |
2012年 | 124篇 |
2011年 | 102篇 |
2010年 | 84篇 |
2009年 | 68篇 |
2008年 | 88篇 |
2007年 | 82篇 |
2006年 | 78篇 |
2005年 | 71篇 |
2004年 | 49篇 |
2003年 | 36篇 |
2002年 | 56篇 |
2001年 | 63篇 |
2000年 | 69篇 |
1999年 | 53篇 |
1998年 | 45篇 |
1997年 | 42篇 |
1996年 | 40篇 |
1995年 | 36篇 |
1994年 | 47篇 |
1993年 | 42篇 |
1992年 | 49篇 |
1991年 | 55篇 |
1990年 | 38篇 |
1989年 | 35篇 |
1988年 | 46篇 |
1987年 | 22篇 |
1986年 | 30篇 |
1985年 | 48篇 |
1984年 | 37篇 |
1983年 | 46篇 |
1982年 | 33篇 |
1981年 | 25篇 |
1980年 | 26篇 |
1979年 | 25篇 |
1978年 | 45篇 |
1977年 | 21篇 |
1976年 | 31篇 |
1975年 | 25篇 |
1974年 | 16篇 |
1972年 | 15篇 |
排序方式: 共有3352条查询结果,搜索用时 890 毫秒
121.
In quantitative trait linkage studies using experimental crosses, the conventional normal location-shift model or other parameterizations may be unnecessarily restrictive. We generalize the mapping problem to a genuine nonparametric setup and provide a robust estimation procedure for the situation where the underlying phenotype distributions are completely unspecified. Classical Wilcoxon–Mann–Whitney statistics are employed for point and interval estimation of QTL positions and effects. 相似文献
122.
In this article, we introduce three new distribution-free Shewhart-type control charts that exploit run and Wilcoxon-type rank-sum statistics to detect possible shifts of a monitored process. Exact formulae for the alarm rate, the run length distribution, and the average run length (ARL) are all derived. A key advantage of these charts is that, due to their nonparametric nature, the false alarm rate (FAR) and in-control run length distribution is the same for all continuous process distributions. Tables are provided for the implementation of the charts for some typical FAR values. Furthermore, a numerical study carried out reveals that the new charts are quite flexible and efficient in detecting shifts to Lehmann-type out-of-control situations. 相似文献
123.
124.
Certain motor vehicle safety standards stipulate a collision test speed and a set of performance criteria that vehicles must satisfy during or after the collision test. For example, Federal Motor Vehicle Safety Standard 301 requires a 30 mile per hour (mph) barrier collision and specifies a certain maximum allowable limit on the total spillage of fuel. Vehicle designs are required to meet this standard; however, when collision tests are conducted at speeds higher than the standard, vehicles do not always satisfy the performance criteria. This paper develops a mathematical model for estimating the probability of meeting the standard by using a Bayesian framework to incorporate engineering judgment with collision test results. The model is based on the idea that there are random features to a vehicle's ability to meet performance standards in a collision, especially at such elevated speeds. Example calculations are included to illustrate the estimation of the probability of meeting the standard and to compare it with a maximum likelihood approach. 相似文献
125.
Evgeny D. Maslennikov Alexey V. Sulimov Igor A. Savkin Marina A. Evdokimova Dmitry A. Zateyshchikov Valery V. Nosikov 《Journal of applied statistics》2015,42(1):71-87
The article focuses on the application of the Bayesian networks (BN) technique to problems of personalized medicine. The simple (intuitive) algorithm of BN optimization with respect to the number of nodes using naive network topology is developed. This algorithm allows to increase the BN prediction quality and to identify the most important variables of the network. The parallel program implementing the algorithm has demonstrated good scalability with an increase in the computational cores number, and it can be applied to the large patients database containing thousands of variables. This program is applied for the prediction for the unfavorable outcome of coronary artery disease (CAD) for patients who survived the acute coronary syndrome (ACS). As a result, the quality of the predictions of the investigated networks was significantly improved and the most important risk factors were detected. The significance of the tumor necrosis factor-alpha gene polymorphism for the prediction of the unfavorable outcome of CAD for patients survived after ACS was revealed for the first time. 相似文献
126.
Sabine S. Nooten Patrick Schultheiss Jules Wright Catriona Macdonald Brajesh K. Singh James M. Cook Sally A. Power 《Urban Ecosystems》2018,21(3):565-576
Recent concern over increasing loss of biodiversity has prompted considerable interest in the role of urban green spaces as reservoirs of local biodiversity. This study assessed the diversity of three indicator taxa - plants, ants and birds - on golf courses spanning a wide range of environmental variation in terms of climate, elevation, course age, size and connectivity to native woodland. Species richness and community composition was further compared between contrasting on-course habitat types that reflect different management intensities. We identified a set of taxon-specific environmental correlates indicating an intricate interplay of landscape- and local-scale variables that affect local species diversity. Our results show that floristic diversity is positively associated with the amount of rainfall, whereas ant and bird diversity are related to local-scale factors, particularly the number of trees and the size of water features on a site. The amount of on-course native habitat was a strong predictor of plant and ant diversity and was also associated with the number of unique species at the site level; this reinforces the value of remnant habitat patches as local biodiversity reservoirs that represent mini hot-spots in an otherwise species-poor urban landscape. Community composition for all three taxa differed markedly between non-playing and playing areas, with boundary and remnant habitats generally having more diverse, species-rich communities. Our results suggest that local floral and faunal biodiversity on urban golf courses can be enhanced by creating woody non-playing areas and, especially, by preserving, restoring or expanding remnant habitats. 相似文献
127.
S. N. Rodda V. Manning N. A. Dowling S. J. Lee D. I. Lubman 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2018,34(1):307-320
Despite high rates of comorbidity between problem gambling and mental health disorders, few studies have examined barriers or facilitators to the implementation of screening for problem gambling in mental health services. This exploratory qualitative study identified key themes associated with screening in mental health services. Semi-structured interviews were undertaken with 30 clinicians and managers from 11 mental health services in Victoria, Australia. Major themes and subthemes were identified using qualitative content analysis. Six themes emerged including competing priorities, importance of routine screening, access to appropriate screening tools, resources, patient responsiveness and workforce development. Barriers to screening included a focus on immediate risk as well as gambling being often considered as a longer-term concern. Clinicians perceived problem gambling as a relatively rare condition, but did acknowledge the need for brief screening. Facilitators to screening were changes to system processes, such as identification of an appropriate brief screening instrument, mandating its use as part of routine screening, as well as funded workforce development activities in the identification and management of problem gambling. 相似文献
128.
129.
Semi-structured interviews were used to explore identity development for nine adoptees (aged 9–23 years) who were adopted by their foster carers in New South Wales, Australia. Adoptions were open, with court-ordered face-to-face contact with birth families. Findings suggest that participants had healthy adoptive identities, with coherent and meaningful narratives about their life histories. Adoption provided a sense of security and belonging. Openness provided information to build a self-narrative and encouraged discussion of adoption issues within adoptive families. Adoptive parents were critical in helping children understand their adoption and facilitating direct contact with birth families, thus laying foundations for positive identity development. 相似文献
130.
Claire Ferguson Sarah Wright Jodi Death Kylie Burgess John Malouff 《Journal of Child Custody》2018,15(2):93-115
This study examined Family Court of Australia (FCA) judicial determinations in parenting disputes when allegations of child sexual abuse (CSA) are made by an interested party, usually the mother. For the study, 156 published judgments from 2013–2015 were examined to measure how often allegations of CSA are substantiated, suspected to be true, and disbelieved. The characteristics most common in substantiated versus unsubstantiated cases, evidence of abuse presented, and resulting parenting orders were assessed. Findings indicate that, against international comparisons, FCA judges substantiate cases very conservatively, with rates of substantiation much lower than in other studies. Allegations made by mothers against fathers were disproportionately unsubstantiated, as were those which did not fall under the Magellan case management system. Cases where the only evidence of CSA was a child’s disclosure and parent’s allegation were common in both substantiated and unsubstantiated cases, meaning that a lack of other evidence does not preclude a positive finding of risk of CSA by the FCA. Those cases also involving a protection order against the accused were more likely to be substantiated. Confirmation biases and a judicial tendency to err on the side of false negatives are discussed. 相似文献