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   11467篇
  免费   300篇
  国内免费   1篇
管理学   1601篇
民族学   61篇
人才学   1篇
人口学   1027篇
丛书文集   61篇
理论方法论   1029篇
综合类   152篇
社会学   5435篇
统计学   2401篇
  2023年   66篇
  2020年   165篇
  2019年   244篇
  2018年   239篇
  2017年   352篇
  2016年   264篇
  2015年   233篇
  2014年   257篇
  2013年   2149篇
  2012年   331篇
  2011年   305篇
  2010年   270篇
  2009年   229篇
  2008年   328篇
  2007年   333篇
  2006年   256篇
  2005年   245篇
  2004年   219篇
  2003年   216篇
  2002年   252篇
  2001年   266篇
  2000年   237篇
  1999年   206篇
  1998年   179篇
  1997年   181篇
  1996年   166篇
  1995年   164篇
  1994年   132篇
  1993年   171篇
  1992年   177篇
  1991年   168篇
  1990年   165篇
  1989年   145篇
  1988年   159篇
  1987年   164篇
  1986年   121篇
  1985年   121篇
  1984年   157篇
  1983年   148篇
  1982年   125篇
  1981年   95篇
  1980年   120篇
  1979年   136篇
  1978年   107篇
  1977年   111篇
  1976年   103篇
  1975年   111篇
  1974年   85篇
  1973年   70篇
  1972年   75篇
排序方式: 共有10000条查询结果,搜索用时 343 毫秒
881.
This article describes the development of a generic loss assessment methodology, which is applicable to earthquake and windstorm perils worldwide. The latest information regarding hazard estimation is first integrated with the parameters that best describe the intensity of the action of both windstorms and earthquakes on building structures, for events with defined average return periods or recurrence intervals. The subsequent evaluation of building vulnerability (damageability) under the action of both earthquake and windstorm loadings utilizes information on damage and loss from past events, along with an assessment of the key building properties (including age and quality of design and construction), to assess information about the ability of buildings to withstand such loadings and hence to assign a building type to the particular risk or portfolio of risks. This predicted damage information is then translated into risk-specific mathematical vulnerability functions, which enable numerical evaluation of the probability of building damage arising at various defined levels. By assigning cost factors to the defined damage levels, the associated computation of total loss at a given level of hazard may be achieved. This developed methodology is universal in the sense that it may be applied successfully to buildings situated in a variety of earthquake and windstorm environments, ranging from very low to extreme levels of hazard. As a loss prediction tool, it enables accurate estimation of losses from potential scenario events linked to defined return periods and, hence, can greatly assist risk assessment and planning.  相似文献   
882.
This paper presents the current Dutchsociotechnical design approach to integralorganizational renewal in a contextual way. Both itsdesign theory and intervention processes are reviewedand some aggregated empirical evidence is presented. Next, thepaper compares the ideas developed in the Dutch approachto those presented in its American, Scandinavian, andAustralian counterparts. It is concluded that, at a meta-level, they all share the ideal ofparticipative democracy, while at the conceptual level,these distinctive approaches appear quite incompatible.Notwithstanding substantial diversity, it is presumed these approaches can be seen as localmanifestations of a single sociotechnicalparadigm.  相似文献   
883.
The p-value-based adjustment of individual endpoints and the global test for an overall inference are the two general approaches for the analysis of multiple endpoints. Statistical procedures developed for testing multivariate outcomes often assume that the multivariate endpoints are either independent or normally distributed. This paper presents a general approach for the analysis of multivariate binary data under the framework of generalized linear models. The generalized estimating equations (GEE) approach is applied to estimate the correlation matrix of the test statistics using the identity and exchangeable working correlation matrices with the model-based as well as robust estimators. The objectives of the approaches are the adjustment of p-values of individual endpoints to identify the affected endpoints as well as the global test of an overall effect. A Monte Carlo simulation was conducted to evaluate the overall family wise error (FWE) rates of the single-step down p-value adjustment approach from two adjustment methods to three global test statistics. The p-value adjustment approach seems to control the FWE better than the global approach Applications of the proposed methods are illustrated by analyzing a carcinogenicity experiment designed to study the dose response trend for 10 tumor sites, and a developmental toxicity experiment with three malformation types: external, visceral, and skeletal.  相似文献   
884.
A class of Kolmogorov-Smirnov and Cramér-von Mises type statistics for testing symmetry about an unknown value is described. These statistics are not distribution-free, however, and, indeed, are not readily amenable to calculation. A linear rank statistic analog of the first component of the Cramér-von Mises type statistic is investigated. Asymptotic non-null properties of these procedures in the normal case are studied, and an efficiency comparison of the Cramér-vonMises statistic, the linear rank statistic analog, the modified Wil-coxon statistic, and the likelihood ratio test is reported.  相似文献   
885.
Cinquante‐six garçons du secondaire ont expliqué pourquoi ils avaient perpétré ou non certains actes de délinquance (combat, vandalisme, vol à l'étalage, usage de drogues). Ils ont aussi ciblé des théories sociologiques de la délinquance qui s'appliquent à leur comportement. Leurs réponses montrent que les deux types de données se recoupent beaucoup. L'effort, la théorie gánérate, les pairs, le contrôle social, les techniques de neutralisation et la prévention sont importants, mais non l'étiquetage ni l'imitation des médias. Une théorie de contingence de la délinquance est proposée. Fifty‐six high school boys were asked to explain in their own words why they had engaged in or refrained from certain delinquencies: fighting, vandalism, petty theft, truancy and drug use. They were also given the opportunity, via a checklist, to tell whether selected sociological theories applied to their behaviour. Their responses revealed considerable overlap in the two forms of data. Strain, general theory, peers, social control, techniques of neutralization and deterrence are important in varying combinations. Labelling and media imitation are not. A contingency theory of delinquency is proposed.  相似文献   
886.
Earlier work with decision trees identified nonseparability as an obstacle to minimizing the conditional expected value, a measure of the risk of extreme events, by the well-known method of averaging out and folding back. This first of two companion papers addresses the conditional expected value that is defined as the expected outcome assuming the exceedance of a threshold β, where β is preselected by the decision maker. An approach is proposed to overcome the need to evaluate all policies in order to identify the optimal policy. The approach is based on the insight that the conditional expected value is separable into two constituent elements of risk and can thus be optimized along with other objectives, including the unconditional expected value of the outcome, by using a multiobjective decision tree. An example of sequential decision making for improving highway capacity is given.  相似文献   
887.
Today's manufacturing enterprises face tremendous competitive pressures. Global competition, together with market demands for customized products delivered just in time, place tremendous pressures on manufacturers. The emerging global economy is rapidly replacing local markets. The emergence of open markets, reductions in trade barriers, and improvements in transportation and communications links have led to a situation where local competition and markets operate in the context of global standards. This open infrastructure allows manufacturers to respond to these challenges by working more closely with their suppliers and customers, and by building extended enterprises across the whole value chain. Such extended enterprises present great challenges in terms of redesigning business processes to create a competitive advantage from the linkages they include. This paper describes the manufacturing philosophies currently in vogue. Any manufacturing or related business will need to use them, albeit tailored to its own circumstances, in one form or the other, to ensure its prosperity.  相似文献   
888.
The two-parent disease-genotype association problem is studied from the point of view of a coefficient of association between the disease phenotype of the child and the disease phenotypes of the parents, in the presence of some genotypic information about the parents. This coefficient of partial association is derived, and certain tests of hypotheses are constructed. The results are shown to be useful in estimation of recurrence risks, and in understanding the nature of the association between child and parental disease phenotypes.  相似文献   
889.
It is recognized in the field of social work that institutionalization of any people produces certain negative and detrimental patterns of behaviour. In geriatrics present practice is away from institutionalization. The aged are encouraged to find employment or interests and to move out of institutions. Emphasis is placed upon individual flats and self-care with any supportive services that are necessary. More and more the emphasis in child care is upon foster care in ordinary homes scattered through the general community and culture to which the children belong.  相似文献   
890.
The author presents a robust F-test for comparing nested linear models. It is suggested that the approach will be attractive to practitioners because it is based on the familiar F-statistic and corresponds to the common practice of reporting F-statistics after removing obvious outliers. It is calibrated in terms of a real parameter that can be directly interpreted as the willingness of the data analyst to remove observations, and the sensitivity of the F-statistic to this parameter is easily examined. The procedure is evaluated with a simulation study where a scale mixture distribution is used to generate outliers. The procedure is also applied to some data where the occurrence of an outlier is confounded with the significance of a regression term. This provides a comparison of two competing models for the data: one removing an outlier and the other including an additional regression term instead.  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