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971.
Using a spatially extensive urban database constructed from the Maryland Biological Stream Survey (MBSS), we describe the relationships of nutrients in small-order streams to eight defined categories of percent catchment urbanization, correlations between chloride and conductivity in urban streams, and relationships between nutrients and chloride with two Maryland-specific indices of biotic integrity for benthic macroinvertebrates and fish assemblages. Stream nutrients become elevated with increasing percent catchment urbanization, followed by increases in all four measured nitrogen species and total phosphorus at catchment urbanization levels greater than 10%. There was a strong collinear relationship (r 2 = 0.90) between chloride and conductivity (trimeans) across all eight urbanization classes, where Cl (mg/L) = −0.397 + 0.188*conductivity (μS/cm). Critical values for all water quality parameters with the two Maryland biological indices were derived using quantile regression, with significant regressions developed for 11 of 16 water quality parameters and the two biotic indices. For nitrate (NO3-N), the critical thresholds between fair and poor stream quality for the two Maryland biological indices were 0.83 mg/L (benthic macroinvertebrate assemblages) and 0.86 mg/L (fish assemblages). Increasing stream nutrient and chloride levels, associated with widespread catchment urbanization intensity, now affect many small streams in Maryland, with implications for decreasing water quality in major tributaries and the Chesapeake Bay.  相似文献   
972.
This study examined the microinteractions of pedestrians in Japan and in the United States as they walked past a confederate. Specifically, the effects of culture, condition (avoid, look-only, and look plus smile) and sex of confederate on glances, smiles, nods, and greetings by passing pedestrians were examined in a field study on over 1000 participants. The hypotheses of (1) lower responsiveness in Japanese pedestrians than in American pedestrians and (2) increased responsiveness as a function of condition were supported in a series of log-linear analyses of pedestrian glances, smiles, nods, and greetings. Both of these main effects were, however, qualified by Culture X Condition interactions on smiles, nods, and greetings, with the large condition effects present in the American pedestrians, but absent in the Japanese pedestrians. The results are discussed in terms of the functions of glances, smiles, nods, and greetings in these brief encounters and how differing cultural norms affect Japanese and American responsiveness. Finally, the limitations of this study and the broader utility of this research paradigm are discussed.
Miles L. PattersonEmail:
  相似文献   
973.
Drawing on interviews with twenty-five mostly white, educated, work-force experienced and class-privileged mothers, this paper explores how these women construct the lactating body as a carefully managed site and breast-feeding as a project—a task to be researched, planned, implemented, and assessed, with reliance on expert knowledge, professional advice, and consumption. The framing of breast-feeding as a project contrasts with the emphases on pleasure, embodied subjectivity, relationality, and empowerment that characterizes much of the recent breast-feeding literature across the humanities and social sciences. I argue that the project frame sheds light on the amount of work and self-discipline involved in compliance with broader middle-class mothering standards set in the consumerist, technological, medicalized, and professionalized contexts that shape parenting in late capitalist America.
Orit AvishaiEmail:
  相似文献   
974.
This article explores the implications of the Federal Reserve’s shift to transparency for recent debates about neoliberalism and neoliberal policymaking. I argue that the evolution of US monetary policy represents a specific instance of what I term the “neoliberal dilemma.” In the context of generally deteriorating economic conditions, policymakers are anxious to escape responsibility for economic outcomes, and yet markets require regulation to function in capitalist economies (Polanyi 2001). How policymakers negotiate these contradictory imperatives involves a continual process of institutional innovation in which functions are transferred to markets, but under the close control of the state. Thus, under transparency, Federal Reserve officials discovered innovations in the policy process that enabled “markets to do the Fed’s work for it.” These innovations enlisted market mechanisms, but did not represent a retreat from the state’s active role in managing the economy.
Greta R. KrippnerEmail:

Greta Krippner   is Assistant Professor of Sociology at the University of Michigan. She is currently completing a book on the financialization of the American economy in the post-1970s period entitled The Fictitious Economy: The State, Financialization, and the Remaking of American Capitalism. New research examines the relationship between financialization and changing patterns of social conflict in US society from the late nineteenth century to the present.  相似文献   
975.
I investigate the earnings differentials among union and nonunion seafarers, across seafarer occupations, and with respective to other transport operatives. The empirical results suggest that the union and nonunion weekly earnings of captains/mates are comparable, and the union earnings gap for sailors/deckhands is positive. The union (nonunion) weekly earnings of captains/mates are 14.7 (30.5) percent greater than those of sailors/deckhands; the union weekly earnings of captains/mates (sailors/deckhands) are 12.6% greater (9.5% less) than those of truck drivers; and the nonunion weekly earnings of captains/mates (sailors/deckhands) are 33.0% greater (6.2% less) than those of truck drivers. The sailor/deckhand and truck driver earnings differentials are contrary to the general belief that the earnings of truck drivers are less than those of other operative occupations involved in transporting intermodal cargo.
Wayne K. TalleyEmail:
  相似文献   
976.
A comprehensive framework for guiding analyses of internal migration is lacking. This study contributes to the family migration literature in three important ways. We develop a multilevel theoretical framework emphasizing an integration of individual-, family-, and neighborhood-level effects; introduce multilevel statistical modeling; and explicitly assess how effects of economic-based explanatory variables vary by gender. Our data are from the Panel Study of Income Dynamics (PSID). We find that the likelihood of a family migrating is affected by economic and non-economic factors, some of which vary by gender. We add to the dual-earner migration literature by finding that wives are not likely to be tied-movers, but husbands are likely to be tied-stayers. Neighborhood factors also are important to the decision to migrate.
Steven Garasky (Corresponding author)Email:
  相似文献   
977.
This research study explores the strategies adopted by 60 parents of children between 3 and 9 years of age considered to have engaged in violent behaviour, within the meaning of the Safe Schools Act (Ontario Ministry of Education, Canada, 2000). This legal framework requires parents to be involved in the decisions concerning their children. Parents’ perceptions of their involvement lead them to develop coping strategies enabling them to play a more active role in such decision making. This article analyzes their perceptions according to a strengths-based approach and seeks to provide a mediation perspective to social work practice with families.
Marie DroletEmail:
  相似文献   
978.
Virtual Interpersonal Touch and Digital Chameleons   总被引:1,自引:0,他引:1  
We studied the characteristics of hand touch with a mechanical device that approximated a handshake, and we then examined the effect of handshake mimicry on assessment of a partner. Two participants interacted with a force-feedback joystick that recorded each of their hand movements individually. The two participants then greeted one another by feeling the recording of the other person’s movements via the force-feedback device. For each dyad, one of the participants actually received his or her own virtual handshake back under the guise that it was the other person’s virtual handshake. Results demonstrated three significant findings. First, for any given participant, a metric that took into account position, angle, speed, and acceleration of the hand movements correlated highly within individuals across two handshakes. Second, across participants, these metrics demonstrated specific differences by gender. Finally, there was an interaction between gender and mimicry, such that male participants liked people who mimicked their handshakes more than female participants did. We discuss the implications of these findings and relate them to theories of social interaction.
Jeremy N. BailensonEmail:
  相似文献   
979.
Direct applications of remote sensing thermal infrared (TIR) data in landscape ecological research are rare due to limitations in the sensors, calibration, and difficulty in interpretation. Currently there is a general lack of methodology for examining the relationship between land surface temperatures (LST) derived from TIR data and landscape patterns extracted from optical sensors. A separation of landscapes into values directly related to their scale and signature is a key step. In this study, a Landsat ETM+ image of Indianapolis, Unites States, acquired on June 22, 2000, was spectrally unmixed (using spectral mixture analysis, SMA) into fraction endmembers of green vegetation, soil, high albedo, and low albedo. Impervious surface was then computed from the high and low albedo images. A hybrid classification procedure was developed to classify the fraction images into seven land use and land cover (LULC) classes. Using the fractional images, the landscape composition and pattern were examined. Next, pixel-based LST measurements were correlated with the landscape fractional components to investigate LULC based relationships between LST and impervious surface and green vegetation fractions. An examination of the relationship between the LULC and LST maps with landscape metrics was finally conducted to deepen understanding of their interactions. Results indicate that SMA-derived fraction images were effective for quantifying the urban morphology and for providing reliable measurements of biophysical variables. LST was found to be positively correlated with impervious surface fraction but negatively correlated with green vegetation fraction. Each temperature zone was associated with a dominant LULC category. Further research should be directed to the theoretical and applied implications of describing such relationships between LULC patterns and urban thermal conditions.
Dengsheng LuEmail:
  相似文献   
980.
We test the human capital interpretation of the experience-earnings profile. Does the upward sloping portion of the experience-earnings profile reflect on-the-job training which in turn causes the experience-productivity profile to slope upwards, or do purely contractual factors determine the nature of life-cycle earnings. Herein, we provide additional evidence on the relationship between productivity and earnings by examining earnings differentials in the UK academic labor market for economists. Using a test first suggested by Mincer, we find that the empirical results are consistent with human capital theory. We find that, although the positive relationship between earnings and experience persists when individual productivity measures are included in the salary equations for lecturers and senior lecturers, the positive relationship becomes statistically insignificant when the same productivity measures are included in the salary equations for professors. For lecturers and senior lecturers, the experience-salary profile properly reflects the structure of the national pay scale rather than variations in individual research productivity. At the professor level, where individual salaries are not determined by a pay scale, the data support the human capital explanation of the positive experience-earnings profile.
Robert J. NewmanEmail:
  相似文献   
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