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11.
    
Solar energy is considered as a potential alternative energy source. The solar cell is classified into three main types: i) solar cells based on bulk silicon materials (monocrystalline, polycrystalline), ii) thin‐film solar cells (CIGS, CdTe, DSSC, etc.), and iii) solar cells based on nanostructures and nanomaterials. Nowadays, commercial solar cells are usually made by bulk silicon material, which requires not only high fabrication costs but also limited performance. In this study, the fabrication of high‐performance solar cells based on hybrid structure of silicon nanowires/poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate)/graphene (SiNW/PEDOT:PSS/Gr) is focused upon. SiNWs with different lengths of 125, 400, 800 nm, and 2 µm are fabricated by a metal‐assisted chemical etching method, and their influence on the performance of the hybrid solar cells is studied and investigated. The experimental results indicate that the suitable SiNW length for the fabrication of the hybrid solar cells is about 400 nm and the best power conversion efficiency obtained is about 9.05%, which is about 2.1 times higher than that of the planar Si solar cell.  相似文献   
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One particular recurrent events data scenario involves patients experiencing events according to a common intensity rate, and then a treatment may be applied. The treatment might be effective for a limited amount of time, so that the intensity rate would be expected to change abruptly when the effect of the treatment wears out. In particular, we allow models for the intensity rate, post-treatment, to be at first decreasing and then change to increasing (and vice versa). Two estimators of the location of this change are proposed.  相似文献   
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Single cohort stage‐frequency data are considered when assessing the stage reached by individuals through destructive sampling. For this type of data, when all hazard rates are assumed constant and equal, Laplace transform methods have been applied in the past to estimate the parameters in each stage‐duration distribution and the overall hazard rates. If hazard rates are not all equal, estimating stage‐duration parameters using Laplace transform methods becomes complex. In this paper, two new models are proposed to estimate stage‐dependent maturation parameters using Laplace transform methods where non‐trivial hazard rates apply. The first model encompasses hazard rates that are constant within each stage but vary between stages. The second model encompasses time‐dependent hazard rates within stages. Moreover, this paper introduces a method for estimating the hazard rate in each stage for the stage‐wise constant hazard rates model. This work presents methods that could be used in specific types of laboratory studies, but the main motivation is to explore the relationships between stage maturation parameters that, in future work, could be exploited in applying Bayesian approaches. The application of the methodology in each model is evaluated using simulated data in order to illustrate the structure of these models.  相似文献   
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How off‐farm employment can enhance welfare in terms of food consumption and poverty alleviation is a critical question facing many developing countries. This study addressed that question by pursuing two objectives: (i) to quantify the impact of off‐farm employment on rural households’ welfare, food security and poverty; and (ii) to examine the factors that affect their decision to work off‐farm. Using panel data, we estimated a difference‐in‐difference combined with a propensity score matching model. The findings show that off‐farm employment improves income, ensures food security and contributes to poverty alleviation. The results also show that age, marital status, education, labour, financial capital, land, location, market access and losses from natural disasters are significant contributing factors to the decision to participate in off‐farm employment. The findings suggest that to improve the welfare of rural households, the Vietnamese government should proceed with policies that enhance their opportunities for participation in off‐farm employment.  相似文献   
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In health technology assessment (HTA), population-adjusted indirect comparisons (PAICs) are increasingly considered to adjust for the difference in the target population between studies. We aim to assess the conduct and reporting of PAICs in recent HTA practice, by performing, a methodological systematic review of studies implementing PAICs from PubMed, EMBASE Classic, Embase/Ovid Medline All, and Cochrane databases from January 1, 2010 to Feb 13, 2023. Four independent researchers screened the titles, abstracts, and full-texts of the identified records, then extracted data on methodological and reporting characteristics of 106 eligible articles. Most PAIC analyses (96.9%, n = 157) were conducted by (or received funding from) pharmaceutical companies. Prior to adjustment, 44.5% of analyses (n = 72) (partially) aligned the eligibility criteria of different studies to enhance the similarity of their target populations. In 37.0% of analyses (n = 60), the clinical and methodological heterogeneity across studies were extensively assessed. In 9.3% of analyses (n = 15), the quality (or bias) of individual studies was evaluated. Among 18 analyses using methods that required an outcome model specification, results of the model fitting procedure were adequately reported in three analyses (16.7%). These findings suggest that the conduct and reporting of PAICs are remarkably heterogeneous and suboptimal in current practice. More recommendations and guidelines on PAICs are thus warranted to enhance the quality of these analyses in the future.  相似文献   
16.
As a newly recognized profession in Vietnam over the last two decades social work has undergone significant development, both in training and practice. However, there are many challenges in its professionalization, in which ethics plays a key role. This article presents the key findings of a study about students‘ perceptions of ethics and developing competence-based ethical standards in social work programs. It first analyses the students‘ attitudes and understanding of professional ethics. Second, it clarifies the situation of ethics education in training institutions. Finally, it provides suggestions for the implementation of social work competence-based ethical standards for Vietnam and beyond.  相似文献   
17.
Pham MH 《Signs》2011,36(2):385-410
As part of a feminist commitment to collaboration, this article appears as a companion essay to Mimi Thi Nguyen's "The Biopower of Beauty: Humanitarian Imperialisms and Global Feminisms" and offers a point of departure for thinking about fashion and beauty as processes that produce subjects recruited to, and aligned with, the national interests of the United States in the war on terror. The Muslim woman in the veil and her imagined opposite in the fashionably modern - and implicitly Western - woman become convenient metaphors for articulating geopolitical contests of power as a human rights concern, as a rescue mission, as a beautifying mandate. This article examines newer iterations of this opposition, in the wake of September 11, 2001, in order to demonstrate the critical resonance of a biopolitics on fashion and beauty. In "The Right to Fashion in the Age of Terrorism," the author examines the relationship between the U.S. war on terror, targeting persons whose sartorial choices are described as terrorist-looking and oppressive, and the right-to-fashion discourse, which promotes fashion's mass-market diffusion as a civil liberty. Looking at these multiple invocations of the democratization of fashion, this article argues that the right-to-fashion discourse colludes with the war on terror by fabricating a neoliberal consumer-citizen who is also a couture-citizen and whose right to fashion reasserts U.S.exceptionalism, which is secured by private property, social mobility, and individualism.  相似文献   
18.
This essay takes as its point of critical departure the digital stardom of Susanna Lau, aka Susie Bubble, the most recognizable and respected fashion blogger in the world, in order to consider the historical formation of success in the postmillennial digital economy. By examining Lau as an embodied sign rather than an exceptional figure of success, I am concerned with the technical, cultural, and economic forces that give shape to hegemonic notions of success and the ideal subject it produces. More specifically, I hope to demonstrate the cultural frames that structure our ways of seeing and recognizing successful individuals in the post millennium by highlighting the gendered and racial construction of the ideal Web 2.0 subject. The aim of my discussion is to show that the discursive construction of Lau's success is reflective of emerging global patterns born out of the rising significance of Asians and young women (especially young Asian women) as consumers and producers in the digital economy.  相似文献   
19.
    
While the collegiate hookup literature identifies the prevalence and conditions under which women engage in same-sex sexual behaviors, less is understood about the macro- and mesolevel features of universities predictive of women’s engagement in these behaviors. How do predictors of same-sex contact differ for women who report engagement in nongenital versus genital sexual acts? Using the Online College Social Life Survey (OCSLS), this study examined 5,069 women from 21 U.S. colleges and universities who reported at least one same-sex encounter in their lifetime to empirically evaluate how same-sex sexual histories are predicted by university structure and membership in student subcultures. Results find subcultural participation to have a regulative effect on what types of sexual behaviors women engaged in with other women. While Greek-affiliated women were significantly more likely to have engaged in solely nongenital sexual behavior, women in team-based athletics were more likely to report a genital sexual history with women. This study’s focus on women’s sexual behaviors as opposed to sexual identity affirms the influence of institutional contexts, subcultural dynamics, and their variability across U.S. campuses in producing the conditions and opportunities for varied forms of sexual interactions among college women.  相似文献   
20.
A central concern over global value chains (GVCs) is whether the integration of national firms into GVCs exacerbates income inequality within countries. However, despite decades of research, the distributional consequences of GVCs remain unclear in the empirical literature. Drawing on panel data from 96 countries between 1980 and 2013, we examine the effects of GVC integration on market income inequality and whether national labour regulations moderate these effects. We find integration increases inequality in the global North and South. More importantly, we find labour regulations amplify the inequality effects of integration in Southern countries by expanding the size of the informal sector while suppressing these effects in Northern countries by promoting unionization. This suggests institutional power from national labour regulations may enhance the bargaining power of labour in the North through increasing collective resources while disempowering labour in the South through reinforcing labour market segmentation between formal and informal sectors.  相似文献   
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