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991.
Since the introduction and definition of relationship algebras by James (1957), rolatively little use has been made of this theory in experimental design and analysis problems This may be due to the underlying theory of relationship algebras being previously accessible only in books on mathematical structure theory, e.g. van der Waerden (1950) This paper provides a development of the theory of relationship algebras beginning at an elementray level and including only those parts of mathematical structure theory which are essential to this development. An example of its application in derving an analysis due to alling (1967) is presented. 相似文献
992.
This paper examines the problem of decisions about the disposal of sewage sludge, in the face of stakeholder groups with varying viewpoints, based on a current case from the state of Lower Saxony in Germany. Like other developed countries, Germany faces the dilemma that sludge arisings are increasing (e.g., because of better water treatment) while disposal options are becoming more scarce. Lower Saxony relies heavily on landfill and agricultural application, but landfill of untreated sludge will be banned after 2005. The state Environment Ministry sees agricultural application as having various advantages, but it faces scepticism from various stakeholders. The ministry has therefore taken steps to encourage a long-term dialogue process with the main stakeholders, including farming organizations, food processors, other landowners such as the churches, and environmental and consumer organizations. The process began with a discussion forum in 1995 that led to the proposal of specific discussions with stakeholders. This paper focuses in particular on the dialogue with environmental and consumer groups. It analyzes the initial positions of the various stakeholders, describes the concrete steps taken so far, describes the ongoing efforts, and critically evaluates the procedures used as well as their implications in terms of the ideas of deliberation and analysis. 相似文献
993.
994.
Use of a conceptual model of societal drivers of ecological change in South Florida: Implications of an ecosystem management scenario 总被引:3,自引:0,他引:3
Harwell Christine C. Deren Christopher W. Snyder George H. Solecki William D. Wilson James Harwell Mark A. 《Urban Ecosystems》1999,3(3-4):345-368
Human-dominated ecosystems such as in South Florida's Everglades region are greatly affected by societal actions and choices, and efforts to restore degraded ecosystems must take into account the societal drivers of ecosystem change. A conceptual model of societal-ecological interactions within the region illustrates connections between major societal drivers, such as water management and land use, and ecological stressors, such as loss of habitat and nutrient loading. Using the conceptual model as an initial guide for discussion, examination of a restoration scenario for the region shows that social and economic effects from activities proposed in a restoration scenario will likely affect most sectors of South Florida. Political effects from changing land and water management practices likely will be significant, as will the physical effects of changing water structures and management practices. Conceptual models such as this can aid in the initial stages of ecosystem restoration discussions and can assist in planning for subsequent social science evaluations of specific societal impacts of actual proposed governmental restoration alternatives. In crafting restoration scenarios, local, regional, and national decision makers can use conceptual models such as this to help broaden the early considerations of how possible future changes in societal drivers, including management choices, will change ecological stressors that affect ecosystem health. 相似文献
995.
This paper considers the situation where a stochastic process may display both long-range dependence (LRD) and intermittency. The existence of such a process is established in Anh et al. (1999). Existing works have commonly paid attention either to LRD or intermittency quite separately. This paper offers a convenient framework to study both effects simultaneously. A method is given to estimate and separate the two effects. The wavelet theory plays an essential role in this procedure. Numerical experiments on fractional Brownian motion and multiplicative cascade processes confirm the power of the method. 相似文献
996.
997.
Katherine C. Pears Hyoun K. Kim Philip A. Fisher 《Children and youth services review》2012,34(12):2361-2366
One hundred ninety-two children in foster care participated in a randomized efficacy trial of a school readiness intervention, the Kids In Transition to School (KITS) Program, designed to increase literacy, social, and self-regulation skills in children before kindergarten entry. One hundred two children were randomly assigned to the KITS intervention and 90 were randomly assigned to the foster care services as usual comparison group. At the end of the kindergarten year, teachers were asked to report on the children's oppositional and aggressive behaviors in the classroom. Controlling for gender, baseline levels of parent-reported oppositional and aggressive behaviors, and level of disruptiveness in the classroom, children who had received the intervention had significantly lower levels of oppositional and aggressive behaviors in the classroom. Findings suggest that an intervention designed to increase school readiness in children in foster care can have positive effects on kindergarten classroom behavior. 相似文献
998.
Clarissa C. David Jenna Mae L. Atun Antonio G. M. La Vi?a 《Population research and policy review》2012,31(2):297-319
This paper investigates the political framing of population in policy discourse through an analysis of legislative documents.
Semantic network analysis was conducted and results were interpreted through discourse analysis of the typical arguments identified.
Policy texts were classified into three sets: population management, reproductive health and family planning, and anti-abortion
and anti-FP. While the “population management” frame focuses on social and economic consequences of population growth, the
“reproductive health” frame defines the problem from a health perspective. Both policies propose aggressive FP programs but
each frame uses distinct political rhetoric and semantic approach in its arguments. The “anti-abortion and anti-FP” frame
identifies two problems: rise in incidence of abortion and existing policy that prohibit health professionals from refusing
patients information on contraception. By invoking a moral argument and anchoring on rights, these policies challenge the
problem and solutions identified by the first two frames. 相似文献
999.
1000.
An extensive amount of criminological research has focused on the relationship between the inability of adolescents to achieve financial success or middle-class status through legitimate channels and their subsequent involvement in delinquency. This genre of research is commonly recognized as structural-strain theory. As the efficacy of this theory has periodically been questioned, this study addresses some of the methodological and theoretical issues associated with structural-strain theory. Using a sample of 8,338 adolescents from a southern state, we use a structural equations model to test a hypothesized sequence ultimately leading to delinquent behavior. We believe that this method is more appropriate than more traditional methods (e.g., multiple regression) for investigating some of the linkages specified in previous strain models. Our results support structural-strain theory, though the hypothesized model has more predictive power among European American than African American youth. Explanations are given for these differential findings, and recommendations for future studies are suggested. 相似文献