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991.
侯旎 《湖南科技大学学报(社会科学版)》2015,18(5):33-39
在科学发现逻辑受制于描述性的传统研究路径,经历衰落和缓慢复苏的大背景之下,计算知识论为科学发现逻辑提供了一个全新的规范性研究框架。该框架不仅为科学发现逻辑做了系统性辩护,而且围绕发现问题的可解性做了许多规范性讨论。虽然其有关具体规范性的研究距离现实的科学发现仍然较远,但这一路径对未来发现逻辑研究走向的启发意义毋庸置疑。 相似文献
992.
郎慧慧 《重庆邮电大学学报(社会科学版)》2018,30(6):16-22
理顺习近平关于“中国特色社会主义进入新时代”的逻辑理路,有助于系统论证“新时代”的科学性和理论性。从方法论上看,习近平新时代观是应用马克思主义立场观点和方法得出的正确结论。从理论归因看,中国社会主要矛盾的转化作为习近平新时代观生成的主要标志,源于马克思主义关于矛盾运动的基本理论。从理论定位看,习近平新时代观展现的是中国发展的特殊阶段,内含着中国对自身发展的时代定位与目标趋向,渗透着中国与世界在共同发展中的新阶段、新高度、新未来,是对中国发展方向的顶层设计。 相似文献
993.
国际投资体系正在遭遇危机,越来越多的国家开始质疑双边投资协定提供的投资者保护制度是否确实有益于增加投资的流动,全球多个国家正在审慎地进行外国投资法的改革。基于此,文章以南非的实践为现实起点,通过概述南非投资保护制度变革的缘由以及深入剖析《投资保护法案》的立法意图,阐明其以国内立法维护公共利益监管权力的法律选择,旨在“一带一路”背景下,为远赴南非的中国投资者提供法律风险的预判,揭示外资法变革对于中国投资者可能产生的影响。对于南非建立新的投资保护制度,其将面临的挑战是如何维持稳定、可预测的投资环境与实现投资保护改革的若干目标之间的平衡。 相似文献
994.
Maria Giulia Olivari Gaia Cuccì Andrea Bonanomi Semira Tagliabue Emanuela Confalonieri 《Marriage & Family Review》2018,54(3):282-295
This study aims to calculate a scaled risk-taking behavior index and to test a model in which maternal and paternal parenting styles affect risk-taking behavior with a mediation of adolescents’ regulatory self-efficacy. Participants were 816 adolescents (44% males) responding to a self-report questionnaire about their risk-taking behavior, regulatory self-efficacy, and retrospective memories of paternal and maternal parenting styles. Results suggested an item rating in the index showing that behaviors considered less risky referred to alcohol use and the unplanned first sexual intercourse, whereas behaviors considered more risky referred to the lack of use of contraceptives and the age of the first sexual intercourse. Results revealed a significant indirect effect of authoritative and authoritarian styles on risk-taking behavior. These styles shaped the adolescents’ regulatory self-efficacy, which in turn predicted adolescent risk-taking behavior. Results underline the complex interplay of relationships between parents and their children. 相似文献
995.
We consider importance sampling (IS) type weighted estimators based on Markov chain Monte Carlo (MCMC) targeting an approximate marginal of the target distribution. In the context of Bayesian latent variable models, the MCMC typically operates on the hyperparameters, and the subsequent weighting may be based on IS or sequential Monte Carlo (SMC), but allows for multilevel techniques as well. The IS approach provides a natural alternative to delayed acceptance (DA) pseudo-marginal/particle MCMC, and has many advantages over DA, including a straightforward parallelization and additional flexibility in MCMC implementation. We detail minimal conditions which ensure strong consistency of the suggested estimators, and provide central limit theorems with expressions for asymptotic variances. We demonstrate how our method can make use of SMC in the state space models context, using Laplace approximations and time-discretized diffusions. Our experimental results are promising and show that the IS-type approach can provide substantial gains relative to an analogous DA scheme, and is often competitive even without parallelization. 相似文献
996.
AbstractWe investigate an optimal investment problem of participating insurance contracts with mortality risk under minimum guarantee. The insurer aims to maximize the expected utility of the terminal payoff. Due to its piecewise payoff structure, this optimization problem is a non-concave utility maximization problem. We adopt a concavification technique and a Lagrange dual method to solve the problem and derive the representations of the optimal wealth process and trading strategies. We also carry out some numerical analysis to show how the portfolio insurance constraint impacts the optimal terminal wealth. 相似文献
997.
Jorge Quiroz Richard Montes Heliang Shi Satrajit Roychoudhury 《Pharmaceutical statistics》2019,18(3):316-328
Assessment of analytical similarity of tier 1 quality attributes is based on a set of hypotheses that tests the mean difference of reference and test products against a margin adjusted for standard deviation of the reference product. Thus, proper assessment of the biosimilarity hypothesis requires statistical tests that account for the uncertainty associated with the estimations of the mean differences and the standard deviation of the reference product. Recently, a linear reformulation of the biosimilarity hypothesis has been proposed, which facilitates development and implementation of statistical tests. These statistical tests account for the uncertainty in the estimation process of all the unknown parameters. In this paper, we survey methods for constructing confidence intervals for testing the linearized reformulation of the biosimilarity hypothesis and also compare the performance of the methods. We discuss test procedures using confidence intervals to make possible comparison among recently developed methods as well as other previously developed methods that have not been applied for demonstrating analytical similarity. A computer simulation study was conducted to compare the performance of the methods based on the ability to maintain the test size and power, as well as computational complexity. We demonstrate the methods using two example applications. At the end, we make recommendations concerning the use of the methods. 相似文献
998.
999.
Andrea Garcia Tapia Mildred Suarez Jose E. Ramirez‐Marquez Kash Barker 《Risk analysis》2019,39(9):2032-2053
Critical infrastructure networks enable social behavior, economic productivity, and the way of life of communities. Disruptions to these cyber–physical–social networks highlight their importance. Recent disruptions caused by natural phenomena, including Hurricanes Harvey and Irma in 2017, have particularly demonstrated the importance of functioning electric power networks. Assessing the economic impact (EI) of electricity outages after a service disruption is a challenging task, particularly when interruption costs vary by the type of electric power use (e.g., residential, commercial, industrial). In contrast with most of the literature, this work proposes an approach to spatially evaluate EIs of disruptions to particular components of the electric power network, thus enabling resilience‐based preparedness planning from economic and community perspectives. Our contribution is a mix‐method approach that combines EI evaluation, component importance analysis, and GIS visualization for decision making. We integrate geographic information systems and an economic evaluation of sporadic electric power outages to provide a tool to assist with prioritizing restoration of power in commercial areas that have the largest impact. By making use of public data describing commercial market value, gross domestic product, and electric area distribution, this article proposes a method to evaluate the EI experienced by commercial districts. A geospatial visualization is presented to observe and compare the areas that are more vulnerable in terms of EI based on the areas covered by each distribution substation. Additionally, a heat map is developed to observe the behavior of disrupted substations to determine the important component exhibiting the highest EI. The proposed resilience analytics approach is applied to analyze outages of substations in the boroughs of New York City. 相似文献
1000.
Jale Tosun Oliver Treib Fabrizio De Francesco 《International Journal of Social Welfare》2019,28(4):358-368
The European Union’s (EU) Youth Guarantee aims to improve the labour market situation of young people. Rather than prescribing a uniform policy model, it acknowledges that supportive measures need to align with national, regional and local circumstances. It thus seeks to promote mutual policy learning through the open method of coordination. As an innovative measure, the EU has deployed funding programmes to support the domestic measures related to the Youth Guarantee. We therefore examined in this study whether this mix of recommendations and financial incentives has entailed a convergence of member state policies. Our analysis of policy outputs for the period 2007?2014 yields a mixed empirical picture. There is catching‐up convergence regarding policies’ sectoral coverage but increasing divergence concerning the number of adopted policy instruments. The first two years of financial incentives did not produce any effect on enhancing policy experimentation among less active member states. We offer an optimistic and a pessimistic interpretation of these findings. 相似文献