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Popular commentaries lament that reforms to the financing of Higher Education (HE) in the UK will operate as a significant deterrent to HE participation amongst students from less advantaged backgrounds. This view of debt as a deterrent is powerful and exists not only at a societal level, but also, as we show, is present in schools. Our data reveal, however, that these ‘debt commentaries’ play out very differently across schools according to the nature of their catchment and the sorts of views staff hold about pupils in relation to their fear of debt. Furthermore, students’ views on debt largely contradict these popular ‘debt-as-deterrent’ narratives and instead are often characterised by acceptance, ambivalence and at times positive orientations towards the prospect of debt. These findings vividly illuminate both the regional and institutional specificity of staff and student decision making in relation to ‘debt’, hence they have substantial implications for HE funding policy specifically and debates about widening participation in HE more generally, where ensuring greater equity in the scope of choices young people have when it comes to choosing a university is a pressing concern.  相似文献   
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In emergent photovoltaics, nanoscale materials hold promise for optimizing device characteristics; however, the related impacts remain uncertain, resulting in challenges to decisions on strategic investment in technology innovation. We integrate multi‐criteria decision analysis (MCDA) and life‐cycle assessment (LCA) results (LCA‐MCDA) as a method of incorporating values of a hypothetical federal acquisition manager into the assessment of risks and benefits of emerging photovoltaic materials. Specifically, we compare adoption of copper zinc tin sulfide (CZTS) devices with molybdenum back contacts to alternative devices employing graphite or graphene instead of molybdenum. LCA impact results are interpreted alongside benefits of substitution including cost reductions and performance improvements through application of multi‐attribute utility theory. To assess the role of uncertainty we apply Monte Carlo simulation and sensitivity analysis. We find that graphene or graphite back contacts outperform molybdenum under most scenarios and assumptions. The use of decision analysis clarifies potential advantages of adopting graphite as a back contact while emphasizing the importance of mitigating conventional impacts of graphene production processes if graphene is used in emerging CZTS devices. Our research further demonstrates that a combination of LCA and MCDA increases the usability of LCA in assessing product sustainability. In particular, this approach identifies the most influential assumptions and data gaps in the analysis and the areas in which either engineering controls or further data collection may be necessary.  相似文献   
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Given a noisy time series (or signal), one may wish to remove the noise from the observed series. Assuming that the noise-free series lies in some low-dimensional subspace of rank r, a common approach is to embed the noisy time series into a Hankel trajectory matrix. The singular value decomposition is then used to deconstruct the Hankel matrix into a sum of rank-one components. We wish to demonstrate that there may be some potential in using difference-based methods of the observed series in order to provide guidance regarding the separation of the noise from the signal, and to estimate the rank of the low-dimensional subspace in which the true signal is assumed to lie.  相似文献   
36.
Due to economic decline and the recent rise in home foreclosure, many U.S. cities are faced with managing large acreages of vacant land. Interest in local food production on this land has the potential to dramatically reshape the composition of greenspace found within urban landscapes. This study examined how the conversion of vacant land to urban gardens and farms influenced arthropod generalist predator populations and their ability to support biocontrol services. We found that the abundance of Coccinellidae and Syrphidae, and the activity density of Carabidae, Formicidae, and Lycosidae were equivalent among vacant lot and urban garden sites. Dolichopodidae abundance and the activity density of Linyphiidae and Opiliones were reduced in urban gardens whereas Anthocoridae abundance and the activity density of Staphylinidae were greater within urban gardens relative to vacant lots. The biocontrol service supplied by generalist predators was measured using sentinel eggs (Helicoverpa zea (Noctuiidae)) and pupae (Sarcophaga bullata (Sarcophagidae) and Musca domestica (Muscidae)). We found no difference in the biocontrol of H. zea eggs or M. domestica pupae among the focal greenspaces. We found no difference in the removal of S. bullata pupae by predators in June 2010, whereas in August 2010 a greater proportion of pupae were removed in urban garden sites relative to vacant lots. Based on these findings, we discuss the potential of the urban landscape to support generalist predators and sustainable urban gardening and farming.  相似文献   
37.
Color-blind racism has transformed how race scholars understand race relations in contemporary society. Previous researchers mainly utilized this theory to identify frames of color-blind racism in various social settings and interactions. What has received less attention, however, is how frames of color-blind racism are produced within material conditions in which social interactions and relations occur. In this study we use film reviews to exemplify how color-blind racism is produced in a specific materialist context—film reviews. Film reviews garner discussion among scholars for their impact on the box office revenues of films. Less attention is given to the content of these reviews and, particularly, how their writers address issues of race. This study provides a qualitative content analysis of film reviewer’s discussions of race in their reviews of twenty-first-century films featuring black protagonists to illuminate some ways in which mainstream and niche media outlets discuss race. Results suggest that the source of the reviews influences how race is considered and communicated among film reviewers. Mainstream reviewers differ widely from niche reviewers in both content and delivery in their discussions of race.  相似文献   
38.
The goal of this study was to examine how aspects of self‐regulation and negative emotionality predicted children's co‐operative and prosocial behavior concurrently and longitudinally using the National Institute of Child Health and Human Development (NICHD) Study of Early Child Care and Youth Development. Mothers completed measures of children's temperamental proneness to negative emotionality and self‐regulation at 54 months. Teachers and parents completed measures of children's co‐operative and prosocial behavior at 54 months, first grade, and third grade. A latent profile analysis of the temperamental variables revealed four profiles of children: those high in regulation and low in negative emotionality, those moderate in regulation and moderate in negative emotionality, those low in regulation and high in negative emotionality, and finally those who were very low in regulation but high in anger emotionality. Generally, children with profiles that were high or moderate in terms of regulation and low or moderate in terms of negative emotionality were rated as the most prosocial and co‐operative. Children with profiles that were less well regulated and who were high in negative emotionality (particularly anger proneness) were rated as less co‐operative and prosocial by parents and teachers.  相似文献   
39.
Robust tests for comparing scale parameters, based on deviances—absolute deviations from the median—are examined. Higgins (2004) proposed a permutation test for comparing two treatments based on the ratio of deviances, but the performance of this procedure has not been investigated. A simulation study examines the performance of Higgins’ test relative to other tests of scale utilizing deviances that have been shown in the literature to have good properties. An extension of Higgins’ procedure to three or more treatments is proposed, and a second simulation study compares its performance to other omnibus tests for comparing scale. While no procedure emerged as a preferred choice in every scenario, Higgins’ tests are found to perform well overall with respect to Type I error rate and power.  相似文献   
40.
The current study examined associations between mothers’ behavioral profiles during mother‐child conflict interactions and their children's social skills. This person‐centered approach classified 181 mothers according to their levels of emotional responsiveness, intrusiveness, negativity, and engagement facilitation behaviors during an eight‐minute conflict discussion task with their child. Three distinct classes of mothers were identified using latent profile analysis: sensitive/engaged, moderately sensitive/engaged, and insensitive/disengaged. An analysis of covariance indicated that children of mothers in the sensitive/engaged group had significantly higher social skills than children of mothers in the moderately sensitive/engaged and insensitive/disengaged groups. Results suggest that mother‐child conflict interactions may benefit children's social development when mothers facilitate their children's participation in a highly sensitive manner.  相似文献   
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