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Skills are core elements of the socio-economic prospects of individuals, while they also improve national productivity, growth and social cohesion. Understanding how skills evolve over time and what drives their evolution has become a policy priority of many European countries. Using the 1994–1998 International Adult Literacy Survey (IALS) and the 2012 Survey on Adult Skills (PIAAC) we build synthetic cohorts and examine how the population gains, loses or preserves cognitive skills (literacy) over time. While, as expected, deterioration in the level of skills due to ageing is common to almost all the European countries studied, for some of them concerns arise for the occurrence of skill deterioration across generations, especially among less well-educated and medium-educated individuals. Certain countries appear to be doing a poorer job in providing the necessary literacy skills over successive generations.  相似文献   
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This paper gives an overview of a participatory ergonomic intervention aimed at reducing low back pain cases in the dispatch department of a catalogue and e-commerce retail company. Based on the findings of the ergonomic analysis and design committee, the company's own employees redesigned the assembly line's layout. As a result of these changes two job tasks that involved manual material handling of boxes, identified by the revised NIOSH equation as posing an increased risk for lifting-related low back pain, were totally eliminated, and the employees responsible for moving boxes from the end of the assembly line to pallets on the ground were given more control over their jobs, and these jobs were also enriched with a new, less heavy task. These results demonstrate that participatory ergonomic interventions are a viable and effective strategy to reduce the exposure to work-related physical and psychosocial risk factors for low back pain.  相似文献   
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Based on semi-structured interviews answered by professionals in Architecture and Interior Design areas, this research aimed to investigate, how these professionals develop their projects. Considering a real situation, the research tried to find out how these professionals consider users necessities and opinions. It was also verified which attributes are considered most relevant and how these professionals correlate them to uses demands about ergonomic aspects and intrinsic characteristics of each project. The paper is concluded presenting a list of attributes that were identified as the most important when developing a design for a home kitchen (as example), and some considerations about this topic are also presented.  相似文献   
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Summary.  Posterior distributions for the joint projections of future temperature and precipitation trends and changes are derived by applying a Bayesian hierachical model to a rich data set of simulated climate from general circulation models. The simulations that are analysed here constitute the future projections on which the Intergovernmental Panel on Climate Change based its recent summary report on the future of our planet's climate, albeit without any sophisticated statistical handling of the data. Here we quantify the uncertainty that is represented by the variable results of the various models and their limited ability to represent the observed climate both at global and at regional scales. We do so in a Bayesian framework, by estimating posterior distributions of the climate change signals in terms of trends or differences between future and current periods, and we fully characterize the uncertain nature of a suite of other parameters, like biases, correlation terms and model-specific precisions. Besides presenting our results in terms of posterior distributions of the climate signals, we offer as an alternative representation of the uncertainties in climate change projections the use of the posterior predictive distribution of a new model's projections. The results from our analysis can find straightforward applications in impact studies, which necessitate not only best guesses but also a full representation of the uncertainty in climate change projections. For water resource and crop models, for example, it is vital to use joint projections of temperature and precipitation to represent the characteristics of future climate best, and our statistical analysis delivers just that.  相似文献   
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A significant decline in biodiversity is associated with the current and upcoming degree of urbanization. A challenging strategy to address this conflict is to make urban growth compatible with biodiversity protection and in this context urban parks can play a crucial role. Urban systems are highly dynamic and complex human-shaped ecosystems, where the relationship between species and environment may be altered and make the preservation of biodiversity within them a challenging goal. In this study, we analysed how different environmental features affect bird biodiversity in one of the most urbanized areas of Italy (the metropolitan area of Milan) at different spatial scales. Bird surveys were conducted in fifteen urban and peri-urban parks and environmental variables at landscape and local scale recorded. Results showed that a mixture of land covers and the presence of water bodies inside urban parks favoured species occurrence and abundance at landscape scale, but a surrounding dense urban matrix deflated biodiversity. At local scale, woodland cover and presence of water bodies were key determinants in ensuring overall high biodiversity but local-specific vegetation management produced an unusual pattern for forests species. In particular, the maintenance of large trees may not result in biodiversity support for forest bird species if large trees are not located in woodland areas with a significant tree density. To understand biodiversity patterns and provide useful information for urban planning and design, we need to provide insights into species/environment relationships at multiple scales in the urban environment.  相似文献   
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Fertility, or childbearing, expectations have been increasingly identified as an important area of research, at least in part because expectations may help us to understand family issues of concern across the globe such as unintended pregnancies, low fertility, and delayed childbearing. While much research has focused on the link between expectations and behavior, this study extends the literature by asking how those expectations were shaped initially. Specifically, we explore how one’s economic context is related to expectations. This paper further extends the literature by focusing on two dimensions of the parenthood expectations of young people (men and women aged 18–27). Using the 2005, 2007, 2009, and 2011 waves of the Panel Studies of Income Dynamics (PSID) Transition to Adulthood (TA) sample, we considered whether young people expected to have children in the future and, for those who did, when they expected to do so. The results support financial-strain theories of the relationship between (subjective and objective) economic circumstances and childbearing expectations. Women and men with lower earnings, less education, and more worries about their future job prospects are more uncertain whether they will have children. Of those who expect to have children, those with more education and more worries expect to do so later in life. Further analyses reveal that race and gender condition these relationships.  相似文献   
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Vine copulas are a highly flexible class of dependence models, which are based on the decomposition of the density into bivariate building blocks. For applications one usually makes the simplifying assumption that copulas of conditional distributions are independent of the variables on which they are conditioned. However this assumption has been criticised for being too restrictive. We examine both simplified and non‐simplified vine copulas in three dimensions and investigate conceptual differences. We show and compare contour surfaces of three‐dimensional vine copula models, which prove to be much more informative than the contour lines of the bivariate marginals. Our investigation shows that non‐simplified vine copulas can exhibit arbitrarily irregular shapes, whereas simplified vine copulas appear to be smooth extrapolations of their bivariate margins to three dimensions. In addition to a variety of constructed examples, we also investigate a three‐dimensional subset of the well‐known uranium data set and visually detect the fact that a non‐simplified vine copula is necessary to capture its complex dependence structure.  相似文献   
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