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151.
Africa has always been potentially one of the richest continents in the world, but, due to a series of causes (colonization
and decolonization process, wars, dictatorships etc.) it has never reached its full potential. The fight against poverty has
been carried out by different institutions at the multilateral and bilateral level during the last 30 years, but the route
toward economic development seems to be still long for African countries. This paper will focus on the analysis of the new
approach to international cooperation introduced by the People’s Republic of China in order to exchange rights of exploitation
of Africa’s mining and natural resources with large amounts of capital without any conditionality. The case-study which will
be considered is the agreement concluded between the People’s Republic of China and the Democratic Republic of Congo. 相似文献
152.
Stockholder and stakeholder perspectives have been positioned in the literature as being in tension, and thus a potential source of innovation and change. However, researchers have overlooked a systematic examination of this presumption in theory and in practice. This study explores the ways that stockholder and stakeholder assumptions are presented by theorists and compares these with expressions of stockholder and stakeholder perspectives used by firms in practice. We argue that theoretical entrenchment dichotomizing these perspectives has disrupted the ability of researchers to leverage this tension. While scholarship remains trapped in a vicious cycle, we also argue that firms in practice express only the acceptance dimension of a virtuous cycle. Our empirical research demonstrates that firms accept and accommodate the paradoxical tension between managing for stockholders versus balancing the interests of stakeholders. This is evidenced by strategies we identify as book‐ending, cadence, continuous and simultaneous co‐mingling, and hybridization. We find that in practice these tensions are more integrated whereas in theory they are treated as more distinct and, often, in conflict. We suggest ways in which both scholarship and practice can better leverage tension as paradoxical opportunity. 相似文献
153.
The amount of radon in natural gas varies with its source. Little has been published about the radon from shale gas to date, making estimates of its impact on radon‐induced lung cancer speculative. We measured radon in natural gas pipelines carrying gas from the Marcellus Shale in Pennsylvania and West Virginia. Radon concentrations ranged from 1,520 to 2,750 Bq/m3 (41–74 pCi/L), and the throughput‐weighted average was 1,983 Bq/m3 (54 pCi/L). Potential radon exposure due to the use of Marcellus Shale gas for cooking and space heating using vent‐free heaters or gas ranges in northeastern U.S. homes and apartments was assessed. Though the measured radon concentrations are higher than what has been previously reported, it is unlikely that exposure from natural gas cooking would exceed 1.2 Bq/m3 (<1% of the U.S. Environmental Protection Agency's action level). Using worst‐case assumptions, we estimate the excess lifetime (70 years) lung cancer risk associated with cooking to be 1.8×10?4 (interval spanning 95% of simulation results: 8.5×10?5, 3.4×10?4). The risk profile for supplemental heating with unvented gas appliances is similar. Individuals using unvented gas appliances to provide primary heating may face lifetime risks as high as 3.9×10?3. Under current housing stock and gas consumption assumptions, expected levels of residential radon exposure due to unvented combustion of Marcellus Shale natural gas in the Northeast United States do not result in a detectable change in the lung cancer death rates. 相似文献
154.
Doubly truncated survival data arise when event times are observed only if they occur within subject specific intervals of times. Existing iterative estimation procedures for doubly truncated data are computationally intensive (Turnbull 38:290–295, 1976; Efron and Petrosian 94:824–825, 1999; Shen 62:835–853, 2010a). These procedures assume that the event time is independent of the truncation times, in the sample space that conforms to their requisite ordering. This type of independence is referred to as quasi-independence. In this paper we identify and consider two special cases of quasi-independence: complete quasi-independence and complete truncation dependence. For the case of complete quasi-independence, we derive the nonparametric maximum likelihood estimator in closed-form. For the case of complete truncation dependence, we derive a closed-form nonparametric estimator that requires some external information, and a semi-parametric maximum likelihood estimator that achieves improved efficiency relative to the standard nonparametric maximum likelihood estimator, in the absence of external information. We demonstrate the consistency and potentially improved efficiency of the estimators in simulation studies, and illustrate their use in application to studies of AIDS incubation and Parkinson’s disease age of onset. 相似文献
155.
中国农村地区的家庭禀赋与外出务工劳动力回流 总被引:5,自引:0,他引:5
中国农村地区家庭禀赋对个人的行为决策有着重要的影响,需要学术界予以更多的关注。为了考察外生性的家庭禀赋对劳动力就业流动的影响,文章通过构建新生代外出务工劳动力和户主子女的回流决策两个计量模型来进行经验论证。分析结果表明,农村劳动力的迁移选择是综合考虑家庭禀赋状况的理性决策,尤其是对于年轻一代的外出劳动力。家庭经济资本的增加会阻碍家庭外出务工成员的回流。外出劳动力回流的概率起初随着家庭人力资本和家庭自然资本的增长而上升,达到一定程度后开始下降。家庭成员只有拥有较为丰富的人力资本,外出务工劳动力才能对家庭社会资本加以充分利用。另外,分析显示年轻一代劳动力和第一代劳动力对家庭社会资本和自然资本的利用是有差异的。 相似文献
156.
The different in the fertility of the rural and urban and future changing trend are very important questions to understand China’s population problem. This paper calculates the fertility of the urban and the rural since 2000 based on the statistical data and compares the fertility rate in the urban and the rural population since 2000. The finding shows that the TFR in the rural is less than 1.8 while the TFR in the urban is less than 1.3 and the difference is narrowing year by year. The fertility difference is mainly caused by the second child, generally speaking the second child fertility tend to increasing slightly while the first child fertility shows dramatic fluctuations because of the Chinese folk culture, the fertility fluctuation in the rural is much dramatic than that in the urban. The mean age at childbearing (MAC) has been delaying in both the rural and the urban areas in the decade. 相似文献
157.
Foster care placement breakdown in the Netherlands and Flanders: Prevalence,precursors, and associated factors 下载免费PDF全文
Johan Vanderfaeillie Anouk Goemans PhD Harm Damen Frank Van Holen Huub Pijnenburg 《Child & Family Social Work》2018,23(3):337-345
Family foster care is the option of choice for children in need of out‐of‐home care in Flanders and the Netherlands. Foster care is however a vulnerable intervention, and questions can be raised as to its efficacy. Although the literature on placement breakdown has made significant progress during the last years, empirical knowledge regarding breakdown in Flanders and the Netherlands remains scant. Consequently, this study aimed at investigating prevalence and precursors of breakdowns in long‐term foster care, the duration of placement before breakdown, and the association of child and placement characteristics with breakdown. Case files of 271 Dutch and 309 Flemish foster children were analysed with a coding scheme designed for this study. After 6 years, 398 placements had terminated: 169 placements broke down and 229 placements ended positively. Placements broke down mainly because of behavioural problems of the foster child, foster parents' parenting problems, and conflicts between birth and foster parents. Foster children with behavioural problems, older foster children, foster children denied treatment, and foster children in care because of sexual abuse were more at risk of breakdown. Assessing these factors is important when evaluating the appropriateness of a family foster care placement. 相似文献
158.
159.
Latent factor models are a useful and intuitive class of models; one limitation is their inability to predict links in a dynamic network. We propose a latent space random effects model with a covariate-defined social space, where the social space is a linear combination of the covariates as estimated by an MCMC algorithm. The model allows for the prediction of links in a network; it also provides an interpretable framework to explain why people connect. We fit the model using the Adolescent Health Network dataset and three simulated networks to illustrate its effectiveness in recognizing patterns in the data. 相似文献
160.
Ken C. Winters PhD Traci Toomey PhD Toben F. Nelson PhD Darin Erickson PhD Kathleen Lenk MPH Mark Miazga JD 《Journal of American college health : J of ACH》2013,61(5):350-357
Abstract Objective: To assess the use of alcohol screening tools across US colleges. Participants: Directors of health services at 333 four-year colleges. Methods: An online survey was conducted regarding the use of alcohol screening tools. Schools reporting use of formal tools were further described in terms of 4 tools (AUDIT, CUGE, CAPS, and RAPS) that the authors judged to be the most favorable based on prior empirical comparative studies. Results: Forty-four percent of colleges reported use of at least 1 formal alcohol screening tool and nearly all of these used a tool appropriate for college students. However, less than half of the 44% of colleges that used a screening tool used 1 of the 4 most favorable tools. Conclusions: Continued efforts are needed to encourage colleges to use the most effective available screening tools to identify alcohol-related problems that require intervention among students. 相似文献