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121.
Background Few investigations have characterized groups of older adults with gambling problems, and published reports are currently limited by small samples of older adult problem gamblers. Gambling helplines represent a widespread mechanism for assisting problem gamblers to move into treatment settings. Given data from older adult problem gamblers in treatment, we hypothesized that older as compared with younger adult problem gamblers calling a gambling helpline would be less likely to report gambling-related problems.Design and methods Logistic regression analyses were performed on data obtained from January 1, 2000 to December 31, 2001, inclusive, from callers with gambling problems (N = 1,084) contacting the Connecticut Council on Problem Gambling Helpline.Results Of the 1,018 phone calls used in the logistic regression analyses, 168 (16.5%) were from older adults and 850 (83.5%) from younger adults. Age-related differences were observed in demographic features, types and patterns of gambling reported as problematic, gambling-related problems and psychiatric symptoms, substance use problems, patterns of indebtedness, and family histories of addictive disorders. Older as compared with younger adult problem gamblers were more likely to report having lower incomes, longer durations of gambling, fewer types of problematic gambling, and problems with casino slot machine gambling and less likely to report gambling-related anxiety, family problems, illegal behaviors and arrests, drug problems, indebtedness to bookies or acquaintances, family histories of drug abuse, and problems with casino table gambling.Conclusions Older as compared with younger adult problem gamblers calling a gambling helpline differ on many clinically relevant features. The findings suggest the need for improved and unique prevention and treatment strategies for older adults with gambling problems.  相似文献   
122.
汽车信息交换平台与行业集成供应链管理模式   总被引:3,自引:0,他引:3  
本文简要介绍了基于中国汽车信息交换平台的汽车行业集成供应链管理模型,对其结构模型进行了分析,指出该管理模型对中国汽车工业发展将发挥重要作用.  相似文献   
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动量效应和反转效应是资本市场的热点话题,学术界给出了诸多解释,但鲜有文献从风险时变性视角关注到波动持续性的影响。基于2005—2021年我国A股市场个股数据,利用GARCH族模型度量股价波动持续性,分别通过投资组合分析与混同横截面分析,实证检验了个股股价波动持续性与股票预期收益之间的关系。研究发现:股价波动持续性与预期收益之间存在显著的负相关关系;通过构建多空组合,在买入波动持续性小的股票的同时卖出波动持续性大的股票,能够获得显著的超额收益。同时,针对我国A股市场存在“反转效应”的特征事实,进一步检验了股价波动持续性对反转收益的影响。经验证据表明,股价波动持续性放大了反转收益。因此,投资者可以通过纳入刻画股价波动持续性与反转效应的因子改善投资组合的业绩;监管部门应加强对股价波动持续性的实时关注,并将其作为系统性风险预警的重点指标。   相似文献   
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新环保法视角下环保NGO公益诉讼分析   总被引:1,自引:0,他引:1  
2014年新修订的环保法赋予了环保NGO公益诉讼的主体资格,可以说是环境公益诉讼史上的一座里程碑。本文通过对近年来环保NGO参与环境公益诉讼面临问题及原因的分析,提出:由于新环保法相关条款的限制性规定、公益诉讼原告诉求保障不足、我国环保NGO自身能力较弱等原因,环保NGO在新环保法颁布后参与环境公益诉讼仍可能面临一定的阻力。应该完善新环保法相关公益诉讼条款、出台激励环保NGO参与环境公益诉讼的具体措施、加强环保NGO的能力建设,以促进新环保法的有效施行。  相似文献   
127.
This article evaluates the association between remittance outflow (RMO) and economic growth in the Gulf Cooperation Council (GCC) countries. The results of this evaluation indicate that RMO Granger creates gross domestic product (GDP) per capita in three countries, namely, Bahrain, Oman and Saudi Arabia. Similarly, the results for causality from GDP per capita to RMO are significant for four countries, namely, Bahrain, Kuwait, Qatar, and Saudi Arabia. The findings differ from those of the household consumption model, stating that higher RMO will decrease economic activity. GDP per capita is the main determinant of RMO, suggesting that economic growth promises and encourages continuous RMO and vice versa. The adverse impact of RMO can be minimized by encouraging the local population to be productive in the private sector, as local productivity will reduce the huge influx of foreign workers and provide valuable local investment opportunities to lessen the amount being remitted.  相似文献   
128.
ABSTRACT

The optimal learner for prediction modeling varies depending on the underlying data-generating distribution. Super Learner (SL) is a generic ensemble learning algorithm that uses cross-validation to select among a ‘library’ of candidate prediction models. While SL has been widely studied in a number of settings, it has not been thoroughly evaluated in large electronic healthcare databases that are common in pharmacoepidemiology and comparative effectiveness research. In this study, we applied and evaluated the performance of SL in its ability to predict the propensity score (PS), the conditional probability of treatment assignment given baseline covariates, using three electronic healthcare databases. We considered a library of algorithms that consisted of both nonparametric and parametric models. We also proposed a novel strategy for prediction modeling that combines SL with the high-dimensional propensity score (hdPS) variable selection algorithm. Predictive performance was assessed using three metrics: the negative log-likelihood, area under the curve (AUC), and time complexity. Results showed that the best individual algorithm, in terms of predictive performance, varied across datasets. The SL was able to adapt to the given dataset and optimize predictive performance relative to any individual learner. Combining the SL with the hdPS was the most consistent prediction method and may be promising for PS estimation and prediction modeling in electronic healthcare databases.  相似文献   
129.
道教音乐中的步虚韵与汉魏清商乐尤其是南方祀神歌有密切渊源,与佛教梵呗也存在同源互通的关系。唐宋时期步虚韵渗入燕乐并迅速流衍盛行,步虚词的齐言、杂言变化对考察声诗、曲子词的转变有重要的参照意义,不少词调如《捣练子》《步虚子令》《忆江南》及《西江月》等都与步虚韵、步虚词相关。  相似文献   
130.
This paper studies approximation algorithm for the maximum weight budgeted connected set cover (MWBCSC) problem. Given an element set \(X\), a collection of sets \({\mathcal {S}}\subseteq 2^X\), a weight function \(w\) on \(X\), a cost function \(c\) on \({\mathcal {S}}\), a connected graph \(G_{\mathcal {S}}\) (called communication graph) on vertex set \({\mathcal {S}}\), and a budget \(L\), the MWBCSC problem is to select a subcollection \({\mathcal {S'}}\subseteq {\mathcal {S}}\) such that the cost \(c({\mathcal {S'}})=\sum _{S\in {\mathcal {S'}}}c(S)\le L\), the subgraph of \(G_{\mathcal {S}}\) induced by \({\mathcal {S'}}\) is connected, and the total weight of elements covered by \({\mathcal {S'}}\) (that is \(\sum _{x\in \bigcup _{S\in {\mathcal {S'}}}S}w(x)\)) is maximized. We present a polynomial time algorithm for this problem with a natural communication graph that has performance ratio \(O((\delta +1)\log n)\), where \(\delta \) is the maximum degree of graph \(G_{\mathcal {S}}\) and \(n\) is the number of sets in \({\mathcal {S}}\). In particular, if every set has cost at most \(L/2\), the performance ratio can be improved to \(O(\log n)\).  相似文献   
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