首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   13013篇
  免费   155篇
  国内免费   50篇
管理学   1620篇
劳动科学   4篇
民族学   154篇
人口学   2456篇
丛书文集   383篇
理论方法论   605篇
综合类   2147篇
社会学   4546篇
统计学   1303篇
  2024年   3篇
  2023年   21篇
  2022年   69篇
  2021年   99篇
  2020年   45篇
  2019年   40篇
  2018年   1695篇
  2017年   1709篇
  2016年   1129篇
  2015年   128篇
  2014年   169篇
  2013年   195篇
  2012年   489篇
  2011年   1369篇
  2010年   1242篇
  2009年   962篇
  2008年   988篇
  2007年   1187篇
  2006年   175篇
  2005年   400篇
  2004年   359篇
  2003年   296篇
  2002年   165篇
  2001年   81篇
  2000年   39篇
  1999年   32篇
  1998年   14篇
  1997年   14篇
  1996年   36篇
  1995年   14篇
  1994年   6篇
  1993年   12篇
  1992年   2篇
  1991年   4篇
  1990年   3篇
  1989年   3篇
  1988年   12篇
  1987年   1篇
  1986年   3篇
  1985年   1篇
  1984年   2篇
  1983年   4篇
  1980年   1篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
The thickness of a graph is the minimum number of planar spanning subgraphs into which the graph can be decomposed. It is known for relatively few classes of graphs, compared to other topological invariants, e.g., genus and crossing number. For the complete bipartite graphs, Beineke et al. (Proc Camb Philos Soc 60:1–5, 1964) gave the answer for most graphs in this family in 1964. In this paper, we derive formulas and bounds for the thickness of some complete k-partite graphs. And some properties for the thickness for the join of two graphs are also obtained.  相似文献   
992.
For a given graph and an integer t, the MinMax 2-Clustering problem asks if there exists a modification of a given graph into two maximal disjoint cliques by inserting or deleting edges such that the number of the editing edges incident to each vertex is at most t. It has been shown that the problem can be solved in polynomial time for \(t<n/4\), where n is the number of vertices. In this paper, we design parameterized algorithms for different ranges of t. Let \(k=t-n/4\). We show that the problem is polynomial-time solvable when roughly \(k<\sqrt{n/32}\). When \(k\in o(n)\), we design a randomized and a deterministic algorithm with sub-exponential time parameterized complexity, i.e., the problem is in SUBEPT. We also show that the problem can be solved in \(O({2}^{n/r}\cdot n^2)\) time for \(k<n/12\) and in \(O(n^2\cdot 2^{3n/4+k})\) time for \(n/12\le k< n/4\), where \(r=2+\lfloor (n/4-3k-2)/(2k+1) \rfloor \ge 2\).  相似文献   
993.
The cutwidth problem for a graph G is to embed G into a path such that the maximum number of overlap edges (i.e., the congestion) is minimized. The investigations of critical graphs and their structures are meaningful in the study of a graph-theoretic parameters. We study the structures of k-cutwidth \((k>1)\) critical trees, and use them to characterize the set of all 4-cutwidth critical trees.  相似文献   
994.
In this paper we analyze the relationship between conformity to executive remuneration standards, corporate ownership, and the level and structure of CEO compensation for large European listed companies in the years 2007 and 2010. We show that controlled corporations conform to executive remuneration standards less than widely held firms. We also show that weaker compliance is associated with lower CEO pay and more cash-based incentive structures. We interpret this “conformity gap” from the perspective of individual firms and from a societal perspective, with the aim to contribute to frame the policy questions concerning executive pay at controlled corporations. Different policy implications depend on whether the conformity gap reflects a lower need for managerial incentives, given the monitoring by controlling shareholders, or the latter’s willingness to extract private benefits of control. We argue in this paper that the former hypothesis prevails, so that regulators should abstain from increasing the level of enforcement of executive remuneration standards.  相似文献   
995.
This article reviews the burdensome problem posed by the arrival in the European countries of large number of refugees and migrants from countries at war or with little economic opportunities. It differentiates the issues of migrants (for economic reasons) and refugees (humanitarian grounds). This wave of refugees currently poses huge challenges to European policy makers. The article suggests some policy initiatives that could solve or at least control the present chaos, disorder, and uncertainty created by the arrival of this unprecedented number of refugees.  相似文献   
996.
From research on Western new product development (NPD) practices a rich body of literature has emerged. However, the impact of country specific and cultural influences has not been examined in this context yet. This study is a first attempt to identify differences in NPD practices between Research and Development (R&D) subsidiaries in Germany, China and India within multinational companies. Data has been generated by qualitative interviews with R&D executives in those countries across multiple cases. The study samples strategic, organizational and operational aspects indicates definite differences in process coordination, rewarding systems, market orientation and the average age of NPD teams. Other aspects like strategic targets, the management involvement, etc. show rather slight differences across the countries. Hence, findings suggest that while some aspects are universally applicable across cultural frontiers, Western companies have to understand different expectations regarding NPD in India and China by adjusting practices accordingly.  相似文献   
997.
Despite the growing trend of logistics outsourcing, there are very limited sources of literature on logistics outsourcing, especially in determining the relationship between factors influencing outsourcing and the extent of logistics outsourcing practices. In this study, we tap into the field of strategic management to help clarify the mechanisms underlying the links between factors influencing, logistics outsourcing practices and outsourcing performance. A model based on the resource based view illustrates the hypothetical connections among these variables. The data gathered from the survey were analysed using SmartPLS software. A response rate of 21 % out of the 486 firms selected was achieved and fixed as the empirical data for this study. The results of this study provide support that superior performance is correlated to the resources of the firm. The analysis shows that lack of human and physical asset capabilities, as well as transaction uncertainty influence the extent of different logistics outsourcing practices. The four logistics outsourcing practices under study were found to have a positive relationship with logistics outsourcing performance, particularly strategic focus. This study shows that although theoretically firms aim at cost reduction by employing a logistics outsourcing strategy but not proven in this study because the financial benefit was only positively contributed by one of the four logistics outsourcing practices under study. Besides that, the results from this study also support that most firms outsource their non-core activities of the logistics practices to respond to the transaction uncertainty that their business experiences.  相似文献   
998.
Cognitive bias is prevalent among gamblers, especially those with gambling problems. Grounded in the heuristics theories, this study contributes to the literature by examining a cognitive bias triggered by the break streak pattern in the casino setting. We postulate that gamblers tend to bet on the latest outcome when there is a break-streak pattern. Moreover, three determinants of the betting decision under break-streak pattern, including the streak length of the alternative outcome, the frequency of the latest outcome, and gender, were identified and examined in this study. A non-participatory observational study was conducted among the Cussec gamblers in a casino in Macao. An analysis of 1229 bets confirms our postulation, particularly when the streak of the alternative outcome is long, the latest outcome is frequent, and the gamblers are females. The findings provide meaningful implications for casino management and public policymakers regarding the minimization of gambling harm.  相似文献   
999.
In 2010 France enacted a law to regulate supply and consumption of online gambling. Its primary aim was to protect citizens from gambling-related harm. This study aims to assess differences in gambling patterns and related harm between online gamblers who use licensed versus unlicensed sites. Participants (N = 3860) completed a self-administered online survey on gambling practices. Pairwise logistic regressions examined the association between the legal statuses of gambling sites people patronized and demographic variables and gambling types. Multivariate logistic regression models explored associations between gambling patterns and related problems according to the legal status of sites people have gambled on. Overall, 53.7 % of online gamblers report gambling exclusively on licensed sites. Those who bet on regulated activities on unlicensed sites, versus licensed sites, are more likely to be female, younger, less educated, inactive in the labor market and are more likely to perceive their financial situation to be difficult. Gambling on unlicensed sites is associated with more intense gambling patterns and more gambling-related problems compared to licensed sites. Findings demonstrate that gambling activities carried out on state licensed sites are associated with less overall harm to gamblers. Implications of these findings on future policy are discussed and prospective research directions are outlined.  相似文献   
1000.
It is generally difficult to separate the effects of divorce from selection when analyzing the effects of parental divorce on children’s risk behaviors. We used propensity score matching and longitudinal data methods to estimate the effects of parents’ divorce on their children’s binge drinking, alcohol consumption, tobacco use, marijuana use, and hard drug use. The children were between 12 and 18 years old in the first survey and between 18 and 24 years old in the second survey. Our results suggest that parental divorce significantly increased the probability of risk behaviors in their children. Moreover, many of these adverse impacts persisted over time, especially among teenage girls.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号