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341.
ARIMA (p, d, q) models were fitted to areal annual rainfall of two homogeneous regions in East Africa with rainfall records extending between the period 1922–80. The areal estimates of the regional rainfall were derived from the time series of the first eigenvector, which was significantly dominant at each of the two regions. The first eigenvector accounted for about 80% of the total rainfall variance in each region.

The class of ARIMA (p, d, q) models which best fitted the areal indices of relative wetness/dryness were the A R M A (3, 1) models. Tests of forecasting skill however indicated low skill in the forecasts given by these models. In all cases the models accounted for less than 50% of the total variance.

Spectral analysis of the indices time series indicated dominant quasi-periodic fluctuations around 2.2–2.8 years, 3–3.7 years, 5–6 years and 10–13 years. These spectral bands however accounted for very low proportion of the total rainfall variance.  相似文献   

342.
The aim of this paper is to describe several methods for quantifying the amount of uncertainty inherent in population forecasts used to assess the impact of demographic processes on social security systems. Each method is briefly outlined, and its advantages and disadvantages are discussed. The primary emphasis is on stochastic population models, and the geographic focus is on the Federal Republic of Germany.  相似文献   
343.
344.
This paper describes the major structural and historical dimensions of health ideology and praxis in the Canadian Arctic. It examines the problems that occur when primary care services exclude their clients from meaningful involvement in planning and administration. It argues that the structure of health services in northern Canada reflects an internal colonial political economy which is characteristic of most Fourth World situations.  相似文献   
345.
"This paper seeks to (1) identify socioeconomic variables that are expected to generate fertility differentials; (2) hypothesize the direction and magnitude of the effect of each variable by reference to a demand-for-children model; and (3) test empirically the model using evidence from Costa Rica. The estimates are obtained from a ten-percent systematic random sample of all Costa Rican individual-family households. There are 15,924 families in the sample...." The authors specifically seek "to capture the effects of changing relative prices and available income and time constraints on parental preferences for children. Least-squares estimates show statistically significant relationships between household fertility and opportunity cost of time, parental education, occurrence of an extended family, medical care, household sanitation, economic sector of employment, and household stock of nonhuman capital."  相似文献   
346.
Puerto Rican migration to the US has been a more or less continuous process since 1917. The perspective of viewing return migration as a circulation process suggests that there are entries, exits, and reintergration into the metropolitan labor market. This study explores the circulatory movements of Puerto Rican families, events that influence the adaptation process when returning to Puerto Rico, and cultural identity aspects. Data collected by means of 2 research instruments that were administered to the respondents simultaneously were used: 1) a life history matrix and 2) an open-ended questionnaire. These interviews outlined the principal problems of adaptation as mentioned by the circulating migrants. The most difficult problems to adjust to were economic and employment (58%), followed by social acceptance (23%), education (17%), and language (15%). Transportation, medical services, and recreational facilities were also problems mentioned as being significant. It is expected that a great majority of migrant laborers will go to live in immigrant residential locations in large US cities. It is also expected that these migrants will meet with certain value conflicts by living in urban ghettos. These families will have serious difficulties finding economic stability and will possibly consider migrating once again as an alternative to their social reality. This study illustrates that: 1) the migrants return in family groups; 2) they face discriminatory problems in employment agencies and schools; 3) they look forward to a formal education as a means of social mobility; 4) they identify themselves with values, habits, and Puerto Rican traditions; and 5) they value the quality of life in Puerto Rico.  相似文献   
347.
Introduction     
In the introduction to this special issue on temporary worker programs, the author defines the term temporary worker and reviews worldwide research, writings, and policies to date pertaining to temporary workers. Labor market and economic effects, socio-administrative conditions, and effects on the labor-sending societies are discussed. Noting that mutually exclusive arguments are presented within one issue of the journal, the author introduces the authors of the individual articles and their subjects. It is determined that the temporary worker phenomenon is now global and that having an understanding of these workers is increasingly central to understanding key socioeconomic and political processes affecting modern industrial and nonindustrial societies.  相似文献   
348.
"This article highlights important developments in the character of temporary worker flows to Canada between 1973 and 1985 through the use of unpublished data and new measures for analyzing this data. The number of employment authorizations are converted to person years to indicate the overall labor market impact of temporary worker flows and this measure is employed in an analysis of unpublished data from Employment and Immigration Canada. The analysis reveals that a significant and growing proportion of employment authorizations are exempted from governmental procedures which link the admission of temporary workers to the Canadian labor market." Reasons for these exemptions and policy implications are discussed  相似文献   
349.
The UN High Commissioner for Refugees (UNHCR) commissioned researchers from the University of Zambia to conduct a socioeconomic survey and census of "spontaneously settled" Zairean and Angolan refugees in the Northwestern Province of Zambia in 1982. The sample consisted of 188 Angolans, 201 Zaireans, and 2 South Africans. The difficulties experienced by refugees in Northwestern Province in achieving integration were related to a combination of factors including the lack of a clear national policy on refugees and refugee status, a national concern for maintaining security, the popular belief that aliens are responsible for an increasing crime rate, the desire by immigration officials for stricter laws to control alien infiltration, conflict between traditional and modern leaders, and Zambia's deteriorating economic situation. In spite of the problems described, the integration of refugees into existing communities is a desirable goal and should be encouraged. One should not assume that self-settling refugees are able to live with ethnic kin, receive assistance and hospitality, and thus are better off than those in camps. The Zambian case provides ample evidence that integration is not easy even with kin support, shared ethnicity, language, and historical connections. Moreover, given the fact that Zambia will continue to receive refugees it is vital that there is a well defined refugee policy and an administrative mechanism for implementing that policy at all levels. This will be particularly important in Zambia as it will undoubtedly continue to receive large influxes of refugees, from countries such as Namibia, Uganda, Angola, Mozambique, and South Africa.  相似文献   
350.
"I describe a course on international demography in this paper. The course enables students to use demographic concepts to understand the demographics of various countries and regions. The course involves an introduction, examination of specific geographic regions, and a concluding overview. I also describe several student projects and review available course materials."  相似文献   
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