全文获取类型
收费全文 | 28875篇 |
免费 | 830篇 |
国内免费 | 1篇 |
专业分类
管理学 | 3975篇 |
民族学 | 151篇 |
人才学 | 1篇 |
人口学 | 2710篇 |
丛书文集 | 128篇 |
教育普及 | 2篇 |
理论方法论 | 2573篇 |
现状及发展 | 1篇 |
综合类 | 296篇 |
社会学 | 14314篇 |
统计学 | 5555篇 |
出版年
2023年 | 192篇 |
2021年 | 175篇 |
2020年 | 475篇 |
2019年 | 685篇 |
2018年 | 821篇 |
2017年 | 1086篇 |
2016年 | 840篇 |
2015年 | 566篇 |
2014年 | 770篇 |
2013年 | 5124篇 |
2012年 | 1024篇 |
2011年 | 941篇 |
2010年 | 708篇 |
2009年 | 607篇 |
2008年 | 751篇 |
2007年 | 709篇 |
2006年 | 717篇 |
2005年 | 618篇 |
2004年 | 620篇 |
2003年 | 534篇 |
2002年 | 580篇 |
2001年 | 709篇 |
2000年 | 651篇 |
1999年 | 618篇 |
1998年 | 464篇 |
1997年 | 408篇 |
1996年 | 419篇 |
1995年 | 430篇 |
1994年 | 354篇 |
1993年 | 386篇 |
1992年 | 429篇 |
1991年 | 417篇 |
1990年 | 424篇 |
1989年 | 400篇 |
1988年 | 378篇 |
1987年 | 320篇 |
1986年 | 358篇 |
1985年 | 392篇 |
1984年 | 356篇 |
1983年 | 332篇 |
1982年 | 264篇 |
1981年 | 221篇 |
1980年 | 242篇 |
1979年 | 293篇 |
1978年 | 207篇 |
1977年 | 194篇 |
1976年 | 168篇 |
1975年 | 163篇 |
1974年 | 162篇 |
1973年 | 134篇 |
排序方式: 共有10000条查询结果,搜索用时 187 毫秒
11.
M. Rae Moors 《Information, Communication & Society》2019,22(6):808-822
ABSTRACTThe Flint Water Crisis became a national news story in January of 2016, when major publishers such as The New York Times began covering the story. In the same month, an influx of social media activism occurred in response to the crisis, with citizens developing hashtag campaigns such as #FlintFwd in order to disseminate news and stories from a citizen’s perspective; these campaigns often positioned Flint positively ? as a recovering community ? rather than a city in the middle of a public health crisis, and often addressed not a national public but a local audience. This paper considers Flint-based social media activity to investigate the emergence of place-based activism within the ostensibly global network of social media. In doing so, it identifies three key themes; 1) leveraging social media to forward a critique of deficient journalistic storytelling; 2) using the affective process of storytelling via social media to claim authority over their own material offline existence, and 3) using place-based storytelling to implicate others as witnesses via the global network of social media. These themes coalesce around a distinctly critical logic of connectivity. This logic extends the notion of connectivity articulated by Van Dijck and Poell [2013. Understanding social media logic. Media and Communication, 1(1), 2–14.] and the strategies of platform activism explored by Tufekci [2017. Twitter and tear gas: The power and fragility of networked protest. New Haven: Yale University Press.] to explain how social media works to expose discrepancies between the public story of the water crisis and material, lived conditions of Flint, rendering visible a discursive identity of Flint thus far unrecognized. 相似文献
12.
Researchers have been developing various extensions and modified forms of the Weibull distribution to enhance its capability for modeling and fitting different data sets. In this note, we investigate the potential usefulness of the new modification to the standard Weibull distribution called odd Weibull distribution in income economic inequality studies. Some mathematical and statistical properties of this model are proposed. We obtain explicit expressions for the first incomplete moment, quantile function, Lorenz and Zenga curves and related inequality indices. In addition to the well-known stochastic order based on Lorenz curve, the stochastic order based on Zenga curve is considered. Since the new generalized Weibull distribution seems to be suitable to model wealth, financial, actuarial and especially income distributions, these findings are fundamental in the understanding of how parameter values are related to inequality. Also, the estimation of parameters by maximum likelihood and moment methods is discussed. Finally, this distribution has been fitted to United States and Austrian income data sets and has been found to fit remarkably well in compare with the other widely used income models. 相似文献
13.
14.
15.
Robert C. Cope Joshua V. Ross Talia A. Wittmann Michael J. Watts Phillip Cassey 《Risk analysis》2019,39(1):35-53
Understanding the risk of biological invasions associated with particular transport pathways and source regions is critical for implementing effective biosecurity management. This may require both a model for physical connectedness between regions, and a measure of environmental similarity, so as to quantify the potential for a species to be transported from a given region and to survive at a destination region. We present an analysis of integrated biosecurity risk into Australia, based on flights and shipping data from each global geopolitical region, and an adaptation of the “range bagging” method to determine environmental matching between regions. Here, we describe global patterns of environmental matching and highlight those regions with many physical connections. We classify patterns of global invasion risk (high to low) into Australian states and territories. We validate our analysis by comparison with global presence data for 844 phytophagous insect pest species, and produce a list of high‐risk species not previously known to be present in Australia. We determined that, of the insect pest species used for validation, the species most likely to be present in Australia were those also present in geopolitical regions with high transport connectivity to Australia, and those regions that were geographically close, and had similar environments. 相似文献
16.
Open innovation and absorptive capacity are two concepts based on the idea that companies can leverage the knowledge generated externally to improve their innovation performance. The aim of this paper is to analyse the joint effect of open innovation and absorptive capacity on a firm's radical innovation. Open innovation is expressed in terms of external search breadth and depth strategies and absorptive capacity is described by distinguishing between potential and realized absorptive capacity. In order to test our hypotheses, we carried out empirical research in firms operating in high-technology industries. The results indicate that internal routines and processes for absorbing external knowledge help explain radical innovation as they show a significant effect of potential and realized absorptive capacity. Also, there is a moderating effect of absorptive capacity on open innovation. Specifically, potential absorptive capacity exerts a positive effect on the relationship between external search breadth and depth and radical innovation. Realized absorptive capacity moderates the influence of external search breadth. These findings confirm the complementary nature of absorptive capacity and open innovation search strategies on radical innovation. 相似文献
17.
A. M. Abd El-Raheem 《Journal of Statistical Computation and Simulation》2019,89(16):3075-3104
The generalized half-normal (GHN) distribution and progressive type-II censoring are considered in this article for studying some statistical inferences of constant-stress accelerated life testing. The EM algorithm is considered to calculate the maximum likelihood estimates. Fisher information matrix is formed depending on the missing information law and it is utilized for structuring the asymptomatic confidence intervals. Further, interval estimation is discussed through bootstrap intervals. The Tierney and Kadane method, importance sampling procedure and Metropolis-Hastings algorithm are utilized to compute Bayesian estimates. Furthermore, predictive estimates for censored data and the related prediction intervals are obtained. We consider three optimality criteria to find out the optimal stress level. A real data set is used to illustrate the importance of GHN distribution as an alternative lifetime model for well-known distributions. Finally, a simulation study is provided with discussion. 相似文献
18.
This article proposes several estimators for estimating the ridge parameter k based on Poisson ridge regression (RR) model. These estimators have been evaluated by means of Monte Carlo simulations. As performance criteria, we have calculated the mean squared error (MSE), the mean value, and the standard deviation of k. The first criterion is commonly used, while the other two have never been used when analyzing Poisson RR. However, these performance criteria are very informative because, if several estimators have an equal estimated MSE, then those with low average value and standard deviation of k should be preferred. Based on the simulated results, we may recommend some biasing parameters that may be useful for the practitioners in the field of health, social, and physical sciences. 相似文献
19.
Fran M. Collyer 《Journal of historical sociology》2021,34(1):41-54
Australia was settled as a colony of Britain from the 17th century, and its early history of violent occupation has gradually given way to a relatively peaceful, wealthy, multicultural society. As a post-colonial country, its people share characteristics with those of Britain, but, as a multicultural society, national identity is increasingly influenced by the cultures of many countries, from both the global North and South. In this paper, the question of Australia's placement as a country of the global North or South is explored. Considerations of geography, the economy, political regimes and national identity are the backdrop to an investigation of Australian scholarship and the attitudes of scholars to the inclusion of Australia as a country of the global South. 相似文献
20.
As important members of research teams, statisticians bear an ethical responsibility to analyze, interpret, and report data honestly and objectively. One way of reinforcing ethical responsibilities is through required courses covering a variety of ethics-related topics at the graduate level. We assessed ethics requirements for graduate-level statistics training programs in the United States for the 2013–2014 academic year using the websites of 88 universities, examining 103 biostatistics programs, and 136 statistics degree programs. We categorized programs’ ethics training requirements as required or not required. Thirty-one (35.1%) universities required an ethics course for at least some degree students. Sixty-two (25.5%) degree programs required an ethics course for at least some students. The majority (77.4%) of required courses were worth 0 or 1 credit. Of the 177 programs without an ethics requirement, 19 (10.7%) listed an ethics elective. Although a single ethics course is insufficient for instilling an ethical approach to science, degree programs that model expectations through coursework point to the value of ethics in science. More training programs should prepare statisticians to consider the ethical dimensions of their work through required coursework. Supplementary materials for this article are available online. 相似文献