全文获取类型
收费全文 | 7438篇 |
免费 | 125篇 |
国内免费 | 1篇 |
专业分类
管理学 | 990篇 |
民族学 | 33篇 |
人口学 | 762篇 |
丛书文集 | 34篇 |
理论方法论 | 664篇 |
综合类 | 91篇 |
社会学 | 3578篇 |
统计学 | 1412篇 |
出版年
2023年 | 40篇 |
2020年 | 97篇 |
2019年 | 142篇 |
2018年 | 168篇 |
2017年 | 253篇 |
2016年 | 179篇 |
2015年 | 124篇 |
2014年 | 160篇 |
2013年 | 1301篇 |
2012年 | 228篇 |
2011年 | 206篇 |
2010年 | 148篇 |
2009年 | 134篇 |
2008年 | 147篇 |
2007年 | 141篇 |
2006年 | 171篇 |
2005年 | 152篇 |
2004年 | 148篇 |
2003年 | 136篇 |
2002年 | 153篇 |
2001年 | 164篇 |
2000年 | 169篇 |
1999年 | 173篇 |
1998年 | 137篇 |
1997年 | 133篇 |
1996年 | 126篇 |
1995年 | 110篇 |
1994年 | 108篇 |
1993年 | 111篇 |
1992年 | 117篇 |
1991年 | 128篇 |
1990年 | 125篇 |
1989年 | 144篇 |
1988年 | 85篇 |
1987年 | 109篇 |
1986年 | 93篇 |
1985年 | 116篇 |
1984年 | 96篇 |
1983年 | 103篇 |
1982年 | 80篇 |
1981年 | 81篇 |
1980年 | 76篇 |
1979年 | 81篇 |
1978年 | 83篇 |
1977年 | 60篇 |
1976年 | 66篇 |
1975年 | 61篇 |
1974年 | 59篇 |
1973年 | 48篇 |
1971年 | 41篇 |
排序方式: 共有7564条查询结果,搜索用时 15 毫秒
891.
Polychlorinated dibenzo-p-dioxin's (PCDD) behavior in the agricultural food chain was modeled in this study. The source of PCDD was a municipal solid waste (MSW) incinerator. Of the farm livestock investigated only the beef cow and the milk cow were shown to contribute significant amounts of PCDD to humans. Milk was the single highest dietary source of PCDD. Comparison of the calculated human dose of PCDD from the agricultural food chain with an estimate human PCDD dose from inhalation of contaminated air revealed that the agricultural food chain could be responsible for a vast majority of the dose to an individual impacted by these facilities. Thus, these data suggest that operating MSW facilities in agricultural areas may result in enhanced PCDD exposure to individuals via the agricultural food chain. The data also suggest that milk and beef may be good sentinels to evaluate environmental impacts of these facilities. 相似文献
892.
893.
Traditional (non-stochastic) iterative methods for optimizing functions with multiple optima require a good procedure for selecting starting points. This paper illustrates how the selection of starting points can be made automatically by using a method based upon simulated annealing. We present a hybrid algorithm, possessing the accuracy of traditional routines, whilst incorporating the reliability of annealing methods, and illustrate its performance for a particularly complex practical problem.Now at the Statistical Laboratory, University of Cambridge, 16 Mill Lane, Cambridge, CB2 1SB, UK. 相似文献
894.
895.
Majority-in-unit (MIU) and method of majority decision (MMD) voting rules are investigated to determine their impact on the
outcome of union elections. A theoretical foundation is established to explain why voters may rationally choose not to vote
in these settings. Numerical simulations are employed to compute the probability that the population majority wins the election.
The results for these two methods are compared to see which one is most likely to award the election to the true population
majority. 相似文献
896.
Lifetime cancer potency of alfatoxin was assessed based on the Yeh et al. study from China in which both aflatoxin exposure and hepatitis B prevalence were measured. This study provides the best available information for estimating the carcinogenic risk posed by aflatoxin to the U.S. population. Cancer potency of aflatoxin was estimated using a biologically motivated risk assessment model. The best estimate of aflatoxin potency was 9 (mg/kg/day)−1 for individuals negative for hepatitis B and 230 (mg/kg/day)−1 for individuals positive for hepatitis B. 相似文献
897.
Selon les auteurs de cette communication, les données tirées d'entrevues avec les décideurs et de l'observation participante au processus d'élaboration des politiques militent en faveur d'une interprétation de la politique canadienne de l'immigration qui s'articule autour du rǒle de l'État. Pour eux, l'État est une entitéà double visage, à la fois puissante et vulnérable, et c'est ce caractère double qui conditionne les tendances actuelles en matière de politique de l'immigration. En élaborant sa politique, l'État cherche activement à accroǐtre sa propre légitimité en adoptant des mesures susceptibles de protéger une économie en difficulté, d'éviter les critiques sur la place publique et d'atténuer les conflits sociaux. L'état vise à assurer son hégémonie, en partie grǎce à un dialogue proactif destiné d'une part à recueillir de l'information et à mesurer les appuis et les oppositions, et d'autre part à contrǒler les divers groupes d'intérět. Ainsi, l'État est maǐtre du champ de l'élaboration des politiques, mais c'est un maǐtre qui se méfie des forces politiques qui pourraient miner sa légitimité. D'après les recherches des auteurs, les nouveaux intervenants, dont les groupes ethniques, les organisations humanitaires et les provinces, jouent un rǒle de plus en plus important dans un domaine dominé par 1'État fédéral. Deux intervenants traditionnels, le mouvement ouvrier et le patronat, en sont Venus à des positions considérablement moins polarisées. Le terrain politique est donc mouvant et plutǒt instable en cette époque où les principaux intervenants, y compris l'État, tentent de se réorienter dans un contexte international en pleine mutation. Data from interviews with policy actors and from participant observation of recent policy process support a particular state-centred interpretation of Canadian immigration policy. The state has a Janus-faced character - both powerful and vulnerable - and it is this ‘both-and’ feature which underlies current trends in immigration policy. Findings in this paper indicate that, in developing immigration policy, the state actively seeks to garner support for its own legitimacy by pursuing measures which will shore up the economy, avoid public criticism and mediate social conflict. The state is engaged in a hegemonic project involving a pro-active dialogue to gather information, to monitor support and opposition, and to attempt to control diverse interest groups. In sum, the state is both in control of the policy field and yet wary of political forces which potentially threaten its legitimacy. Our research shows that new social actors -ethnic groups, humanitarian organizations, the provinces - have come to play a more prominent role, within a field dominated by the federal state. Two traditional actors, labour and capital, have moved to less polarized views. The policy arena is shifting and prone to be unstable, as the key actors involved, including the state, struggle to come to terms with a changing global context. 相似文献
898.
Pauline B. Bart 《Qualitative sociology》1987,10(4):339-357
This paper describes an illegal feminist abortion collective [the Service] through whose efforts 11,000 abortions were performed between 1969 and 1973 when abortion was legalized. An analysis of interviews from 32 members of this lay group indicates how and why the collective was so effective in providing what is usually a physician-controlled medical procedure. After describing the structure of the organization and the process by which women obtained the abortion, including pre-abortion counseling and post-abortion follow-up, two sets of reasons for the collective's effectiveness are presented. The first five reasons derive from the interview themselves; they deal with the organization's social and historical context, its illegality, its charismatic leaders, its member satisfaction and its financial self-sufficiency. The next nine reasons deal with factors that make The Service a relatively typical democratic collective organization. The most important of these factors is its lack of concern for organizational survival per se. This account supports the Rothschild-Whitt model for collective democratic organizations. It also suggests that counseling is important both for the providers and for the receivers of abortions. 相似文献
899.
900.
Chien‐Ming Chen Yeming Gong Ren B.M. De Koster Jo A.E.E. Van Nunen 《Production and Operations Management》2010,19(1):70-82
This paper develops a novel framework to evaluate the integral performance of order picking systems with different combinations of storage and order picking policies. The warehousing literature on order picking mostly considers minimizing either elapsed time or distance as the sole objective, whereas warehouse managers in a supply chain have to look beyond single‐dimensional performance and consider trade‐offs among different criteria. Thus managers still need a unified and efficient framework to select a portfolio of appropriate order picking policies from a multi‐criteria and contextual perspective. Our framework—combining data envelopment analysis, ranking and selection, and multiple comparisons—provides an efficient methodology to simultaneously analyze several interrelated problems in order picking systems with multiple performance attributes, such as service levels and operational costs. We demonstrate our approach through comprehensive evaluations of order picking policies in three low‐level, picker‐to‐parts rectangular warehouses facing demand variations. 相似文献