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   2897篇
  免费   98篇
  国内免费   11篇
管理学   163篇
民族学   13篇
人才学   2篇
人口学   21篇
丛书文集   488篇
理论方法论   74篇
综合类   1870篇
社会学   50篇
统计学   325篇
  2023年   10篇
  2022年   10篇
  2021年   13篇
  2020年   57篇
  2019年   37篇
  2018年   32篇
  2017年   44篇
  2016年   39篇
  2015年   54篇
  2014年   253篇
  2013年   288篇
  2012年   152篇
  2011年   189篇
  2010年   131篇
  2009年   142篇
  2008年   183篇
  2007年   202篇
  2006年   193篇
  2005年   189篇
  2004年   145篇
  2003年   199篇
  2002年   155篇
  2001年   106篇
  2000年   77篇
  1999年   31篇
  1998年   9篇
  1997年   4篇
  1996年   7篇
  1995年   6篇
  1994年   12篇
  1993年   5篇
  1992年   11篇
  1991年   3篇
  1990年   3篇
  1989年   4篇
  1988年   2篇
  1987年   3篇
  1985年   3篇
  1984年   1篇
  1980年   1篇
  1976年   1篇
排序方式: 共有3006条查询结果,搜索用时 62 毫秒
11.
文章简要阐述了反馈信息,论述了作文工作研究的意义及在作文写作中有效的信息反馈形式,提出了增强写作能力的可行措施。  相似文献   
12.
读者接受理论为文学翻译提供了一个更为开放的视角,值得重视和借鉴。然而,如果全盘接受读者接受理论的观点,把文学翻译仅仅看作一种译者主体行为,势必会导致不准确的翻译。读者对于文化空缺词的接受能力是一个历史的动态变化过程。  相似文献   
13.
Quantifying uncertainty in the biospheric carbon flux for England and Wales   总被引:1,自引:0,他引:1  
Summary.  A crucial issue in the current global warming debate is the effect of vegetation and soils on carbon dioxide (CO2) concentrations in the atmosphere. Vegetation can extract CO2 through photosynthesis, but respiration, decay of soil organic matter and disturbance effects such as fire return it to the atmosphere. The balance of these processes is the net carbon flux. To estimate the biospheric carbon flux for England and Wales, we address the statistical problem of inference for the sum of multiple outputs from a complex deterministic computer code whose input parameters are uncertain. The code is a process model which simulates the carbon dynamics of vegetation and soils, including the amount of carbon that is stored as a result of photosynthesis and the amount that is returned to the atmosphere through respiration. The aggregation of outputs corresponding to multiple sites and types of vegetation in a region gives an estimate of the total carbon flux for that region over a period of time. Expert prior opinions are elicited for marginal uncertainty about the relevant input parameters and for correlations of inputs between sites. A Gaussian process model is used to build emulators of the multiple code outputs and Bayesian uncertainty analysis is then used to propagate uncertainty in the input parameters through to uncertainty on the aggregated output. Numerical results are presented for England and Wales in the year 2000. It is estimated that vegetation and soils in England and Wales constituted a net sink of 7.55 Mt C (1 Mt C = 1012 g of carbon) in 2000, with standard deviation 0.56 Mt C resulting from the sources of uncertainty that are considered.  相似文献   
14.
Approximation formulae are developed for the bias of ordinary and generalized Least Squares Dummy Variable (LSDV) estimators in dynamic panel data models. Results from Kiviet [Kiviet, J. F. (1995), on bias, inconsistency, and efficiency of various estimators in dynamic panel data models, J. Econometrics68:53-78; Kiviet, J. F. (1999), Expectations of expansions for estimators in a dynamic panel data model: some results for weakly exogenous regressors, In: Hsiao, C., Lahiri, K., Lee, L-F., Pesaran, M. H., eds., Analysis of Panels and Limited Dependent Variables, Cambridge: Cambridge University Press, pp. 199-225] are extended to higher-order dynamic panel data models with general covariance structure. The focus is on estimation of both short- and long-run coefficients. The results show that proper modelling of the disturbance covariance structure is indispensable. The bias approximations are used to construct bias corrected estimators which are then applied to quarterly data from 14 European Union countries. Money demand functions for M1, M2 and M3 are estimated for the EU area as a whole for the period 1991: I-1995: IV. Significant spillovers between countries are found reflecting the dependence of domestic money demand on foreign developments. The empirical results show that in general plausible long-run effects are obtained by the bias corrected estimators. Moreover, finite sample bias, although of moderate magnitude, is present underlining the importance of more refined estimation techniques. Also the efficiency gains by exploiting the heteroscedasticity and cross-correlation patterns between countries are sometimes considerable.  相似文献   
15.
<中国语言生活状况报告(2005)>对现代汉字和汉语词汇使用现状的反映,是迄今为止语料量最大,词种数最多,发布单位最为权威的调查数据.这是一份反映了新闻语言真实面貌的言语词性质的词表.语文词是社会流通词语总汇中的主体,它有着高频性、高分布率、短小化的特点;从高频词身上可以清晰地观察到社会发展与社会文化.  相似文献   
16.
MODEL-ASSISTED HIGHER-ORDER CALIBRATION OF ESTIMATORS OF VARIANCE   总被引:1,自引:0,他引:1  
In survey sampling, interest often centres on inference for the population total using information about an auxiliary variable. The variance of the estimator used plays a key role in such inference. This study develops a new set of higher‐order constraints for the calibration of estimators of variance for various estimators of the population total. The proposed strategy requires an appropriate model for describing the relationship between the response and auxiliary variable, and the variance of the auxiliary variable. It is therefore referred to as a model‐assisted approach. Several new estimators of variance, including the higher‐order calibration estimators of the variance of the ratio and regression estimators suggested by Singh, Horn & Yu and Sitter & Wu are special cases of the proposed technique. The paper presents and discusses the results of an empirical study to compare the performance of the proposed estimators and existing counterparts.  相似文献   
17.
在<骆驼祥子>中,虎妞是作为一个相貌丑陋、品行不端、对祥子悲剧负有不可推卸责任的人物出现的.本文从人性和伦理的角度分析,认为虎妞在祥子的悲剧中不应负有过多的责任,事实上她也是一个受害者.而且她还有一些属于她自己的品质精明强干,谙于算计,泼辣直率.  相似文献   
18.
科技英语词汇的特色   总被引:3,自引:0,他引:3  
论述了科技英语词汇的三大组成部分——普通词汇、次技术词汇及技术词汇以及三大组成部分词汇的构成与使用特色,从而为理解科技英语词汇及破译新词汇提供了有效的解决方法。  相似文献   
19.
本文解释了五个汉译佛经《大藏经》中的词语:消息、宁可、巨细、障石疑、缭戾,并一一加以溯源。  相似文献   
20.
Summary.  We consider a Bayesian forecasting system to predict the dispersal of contamination on a large scale grid in the event of an accidental release of radioactivity. The statistical model is built on a physical model for atmospheric dispersion and transport called MATCH. Our spatiotemporal model is a dynamic linear model where the state parameters are the (essentially, deterministic) predictions of MATCH; the distributions of these are updated sequentially in the light of monitoring data. One of the distinguishing features of the model is that the number of these parameters is very large (typically several hundreds of thousands) and we discuss practical issues arising in its implementation as a realtime model. Our procedures have been checked against a variational approach which is used widely in the atmospheric sciences. The results of the model are applied to test data from a tracer experiment.  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