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51.
Previous studies suggest significant differences between navigating virtual environments in a life-like walking manner (i.e., using treadmills or walk-in-place techniques) and virtual navigation (i.e., flying while really standing). The latter option, which usually involves hand-centric devices (e.g., joysticks), is the most common in Virtual Reality-based studies, mostly due to low costs, less space and technology demands. However, recently, new interaction devices, originally conceived for videogames have become available offering interesting potentialities for research. This study aimed to explore the potentialities of the Nintendo Wii Balance Board as a navigation interface in a Virtual Environment presented in an immersive Virtual Reality system. Comparing participants' performance while engaged in a simulated emergency egress allows determining the adequacy of such alternative navigation interface on the basis of empirical results. Forty university students participated in this study. Results show that participants were more efficient when performing navigation tasks using the Joystick than with the Balance Board. However there were no significantly differences in the behavioral compliance with exit signs. Therefore, this study suggests that, at least for tasks similar to the studied, the Balance Board have good potentiality to be used as a navigation interface for Virtual Reality systems.  相似文献   
52.
This paper introduces the Ergonomic Work Analysis as a relevant instrument to identify the risks in occupational environments through the investigation of factors that influence the relationship between the worker and the productive process. It draws a parallel between the several aspects of risk identification in traditional tools of Health and Safety Management and the factors embraced by the Ergonomic Work Analysis, showing that the ergonomic methodology is able to go deeper in the scenarios of possible incident causes. This deepening enables the establishment of a relationship between the work context and the upcoming damage to the physical integrity of the worker. It acts as a complementary instrument in the traditional approach to the risk management. In order to explain the application of this methodology in a preventive way, it is presented a case study of a coal mill inspector in a siderurgic company.  相似文献   
53.
54.
This project is about the usability of Learning Management Systems (LMS), focusing on the specific case of the open source system Moodle. Specifically, this project is about communication and collaboration tools that are used by teachers on the system. This study investigates whether usability problems hamper the use teachers make of these tools. Focused interviews were conducted with professionals working in distance education and the answers of the respondents were subjected to techniques of content analysis in order to obtain data for developing the tools needed to prove the hypothesis.  相似文献   
55.
This experiment investigated the effect of peer discouragement on adolescent risk taking. Overall, 269 Dutch adolescents aged 11–15 years completed a risk taking computer task in the presence of an e‐confederate who demonstrated very little risk taking (passive peer discouragement) and/or sent risk‐discouraging messages to participants (active peer discouragement). The results showed that, compared to a situation with no peer discouragement, adolescents took significantly less risk only when they encountered a combination of active and passive peer discouragement; hence, when peers practiced what they preached. No gender differences were found in the effect of passive and active peer discouragement on risk taking. The results showed that digital peer messages play a promising role in diminishing adolescent risk taking.  相似文献   
56.
The customization of a secretary workstation at a drama school was the objective of this case study. The investigation involved a 25-year-old illiterate woman with intellectual disabilities and low vision that had been been attending, for over 12 years, a state school for people with disabilities. The customization process, operationalized after a diagnosis was made, focused on environmental rearrangements, with the purpose of meeting the physical and social demands of the workstation. The results of this research are configured in an ergonomic analysis of work associated with an inventory of social skills, applied to people living directly with the participant. Preliminary evaluations indicated the degree of adjustment of labor demands to the personal characteristics of the participant in the customized job.  相似文献   
57.
In this paper, we study the impact of macro- and micro-economic uncertainty on family formation between 1970 and 2000 in The Netherlands. Using data of the Family Survey Dutch Population, we analysed the monthly hazard rates of experiencing the transition into first union, first marriage and parenthood after the start of the relationship of 365 male and 364 female partners by applying piecewise-constant exponential models. The results show that macro-economic uncertainties, i.e. high unemployment rates, lead to postponement of the first union and marriage, but not of the first child. In addition, we found that this relationship is not interpreted by individual-level employment insecurity, i.e. temporary employment or unemployment, which does not seem to prevent people from making long-term family commitments. Although hypothesized, we did not find that the negative effects of macro- and micro-level insecurities on family formation reinforce each other or that they vary between individuals with different educational qualifications.  相似文献   
58.

Background

Ice-pack is widely used for alleviating postpartum perineal pain sustained after birth related perineal trauma. However, it lacks robust evidence on timing and frequency of applications, to ensure the effective and safe use of this therapy.

Aims

To evaluate if a 10 min ice-pack application relieved postpartum perineal pain and if the analgesic effect was maintained for up to 2 h.

Methods

A randomised controlled trial conducted from December 2012 to February 2013 with 69 primiparous women ≥18 years old, 6–24 h postpartum, with perineal pain ≥3, who had not received anti-inflammatory medication or analgesics after childbirth, who were randomised to a single ice-pack application on the perineum for 10 min or standard care. The primary and secondary outcomes were a reduction ≥30% in perineal pain intensity, immediately after the application and the maintenance of the analgesic effect for up to 2 h, respectively.

Findings

Immediately post-intervention, the proportion of women whose perineal pain decreased ≥30% was significantly higher in the experimental group. Within 2 h, there was no significant difference in the pain levels in both groups. Within 2 h, for 61.9% and 89.3% of women in the experimental and control group, respectively, the perineal pain levels remained unchanged. For the remaining participants, perineal pain was increasing after an average time of 1 h 45 min and 1 h 56 min for the experimental and control groups, respectively.

Conclusion

By applying an ice-pack for 10 min to the perineum, effective pain relief is achieved, that is maintained for between 1 h 45 min and 2 h.  相似文献   
59.
In the economic and social aftermath of the 2008 crisis there has been an important and growing new wave of highly qualified Portuguese emigration comprising scientists. No or very few public policies have been designed to reverse this phenomenon, risking the consequences of brain drain. International literature argues that professional reasons are central to scientists’ decision to migrate, even after the 2008 crisis. Spending some time in a foreign country to study, research, or teach, is perceived as a common step in an individual academic trajectory and an advantage for a successful professional career in academia. It is also encouraged by European Union policies. Twelve individual portraits of Portuguese scientists living in central Europe reveal how important other factors are to the migration decision‐making process. These factors include the economic crisis, student mobility programmes, and the current Portuguese scientific system revision.  相似文献   
60.
High-content automated imaging platforms allow the multiplexing of several targets simultaneously to generate multi-parametric single-cell data sets over extended periods of time. Typically, standard simple measures such as mean value of all cells at every time point are calculated to summarize the temporal process, resulting in loss of time dynamics of the single cells. Multiple experiments are performed but observation time points are not necessarily identical, leading to difficulties when integrating summary measures from different experiments. We used functional data analysis to analyze continuous curve data, where the temporal process of a response variable for each single cell can be described using a smooth curve. This allows analyses to be performed on continuous functions, rather than on original discrete data points. Functional regression models were applied to determine common temporal characteristics of a set of single cell curves and random effects were employed in the models to explain variation between experiments. The aim of the multiplexing approach is to simultaneously analyze the effect of a large number of compounds in comparison to control to discriminate between their mode of action. Functional principal component analysis based on T-statistic curves for pairwise comparison to control was used to study time-dependent compound effects.  相似文献   
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