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141.
On July 1, 1982 China's 3rd national population census reported the population of the 29 provinces, municipalities, and autonomous regions on the mainland at 1,008,175,288, showing a net increase of 460,000,000 or 84% over the 548,000,000 recorded at the end of 1949. At this time China's population is about 1/4 of the world. Its population policy must conform to her national conditions and will be successful only to the extent that it does so. Discussion focuses on the main features of China's population policy. In 1953 the State Council instructed the Ministry of Health to support birth control by providing contraceptives. It also ratified provisions concerning contraception and induced abortions. In 1962 the State Council issued "Instructions on Conscientious Advocacy of Family Planning." China not only advocates and publicized family planning but also takes specific measures. Special administrative organizations were established in 1964 to oversee scientific research, production, and supply of contraceptives and to provide couples of childbearing age with free contraceptives. An all round attack on family planning work in 1966 led to unchecked childbirth resulting in rapid population growth. In 1971 Premier Zhou Enlai reiterated the importance of population control in 1971 and asked that it be incorporated into the 4th Five Year Plan for the development of the national economy. Family planning was incorporated into the Constitution in 1978. China's 20 years of experiences with family planning suggest that a country's population policy becomes effective only with repeated efforts. The 10-year period of turmoil undermined the enforcement of the population policy. Recently the State Family Planning Commission organized a nationwide fertility survey which indicated tremendous successes for China's population control drive. The total fertility rate dropped from 5.29 in the 1950s to 2.63 in the 1980s. The population census shows that the momentum of China's population growth cannot be checked without strict measures because the population is characterized by a huge base figure, a young age composition, and a fertility rate much higher than a population replacement level. China's population policy is formulated in line with her national conditions. Specific provisions for family planning reflect different ways to deal with different people.  相似文献   
142.
The author examines the motivating factors involved in the migration from Israel of kibbutz and non-kibbutz populations. "The burden of the research done until now suggests that an individual's level of commitment is a major predictor of the predisposition to emigrate. This research will be surveyed, reanalyzed in part, with new emphasis on ethnicity and class, and compared with new research on emigration from the kibbutzim which should provide unique insights into the connection between commitment and departure." Data are from two surveys, a 1986 survey of the general population and one of four kibbutzim in 1985.  相似文献   
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This study presents a tree‐based logistic regression approach to assessing work zone casualty risk, which is defined as the probability of a vehicle occupant being killed or injured in a work zone crash. First, a decision tree approach is employed to determine the tree structure and interacting factors. Based on the Michigan M‐94I‐94I‐94BLI‐94BR highway work zone crash data, an optimal tree comprising four leaf nodes is first determined and the interacting factors are found to be airbag, occupant identity (i.e., driver, passenger), and gender. The data are then split into four groups according to the tree structure. Finally, the logistic regression analysis is separately conducted for each group. The results show that the proposed approach outperforms the pure decision tree model because the former has the capability of examining the marginal effects of risk factors. Compared with the pure logistic regression method, the proposed approach avoids the variable interaction effects so that it significantly improves the prediction accuracy.  相似文献   
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Summary.  The process of quality control of micrometeorological and carbon dioxide (CO2) flux data can be subjective and may lack repeatability, which would undermine the results of many studies. Multivariate statistical methods and time series analysis were used together and independently to detect and replace outliers in CO2 flux data derived from a Bowen ratio energy balance system. The results were compared with those produced by five experts who applied the current and potentially subjective protocol. All protocols were tested on the same set of three 5-day periods, when measurements were conducted in an abandoned agricultural field. The concordance of the protocols was evaluated by using the experts' opinion (mean ± 1.96 standard deviations) as a reference interval (the Bland–Altman method). Analysing the 15 days together, the statistical protocol that combined multivariate distance, multiple linear regression and time series analysis showed a concordance of 93% on a 20-min flux basis and 87% on a daily basis (only 2 days fell outside the reference interval), and the overall flux differed only by 1.7% (3.2 g CO2 m−2). An automated version of this or a similar statistical protocol could be used as a standard way of filling gaps and processing data from Bowen ratio energy balance and other techniques (e.g. eddy covariance). This would enforce objectivity in comparisons of CO2 flux data that are generated by different research groups and streamline the protocols for quality control.  相似文献   
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Research suggests that hurricane‐related risk perception is a critical predictor of behavioral response, such as evacuation. Less is known, however, about the precursors of these subjective risk judgments, especially when time has elapsed from a focal event. Drawing broadly from the risk communication, social psychology, and natural hazards literature, and specifically from concepts adapted from the risk information seeking and processing model and the protective action decision model, we examine how individuals’ distant recollections, including attribution of responsibility for the effects of a storm, attitude toward relevant information, and past hurricane experience, relate to risk judgment for a future, similar event. The present study reports on a survey involving U.S. residents in Connecticut, New Jersey, and New York (n = 619) impacted by Hurricane Sandy. While some results confirm past findings, such as that hurricane experience increases risk judgment, others suggest additional complexity, such as how various types of experience (e.g., having evacuated vs. having experienced losses) may heighten or attenuate individual‐level judgments of responsibility. We suggest avenues for future research, as well as implications for federal agencies involved in severe weather/natural hazard forecasting and communication with public audiences.  相似文献   
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