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   550篇
  免费   10篇
  国内免费   5篇
管理学   100篇
民族学   1篇
人口学   2篇
丛书文集   23篇
理论方法论   8篇
综合类   343篇
社会学   8篇
统计学   80篇
  2024年   1篇
  2023年   2篇
  2022年   2篇
  2021年   1篇
  2020年   4篇
  2019年   3篇
  2018年   12篇
  2017年   18篇
  2016年   17篇
  2015年   11篇
  2014年   16篇
  2013年   36篇
  2012年   20篇
  2011年   25篇
  2010年   32篇
  2009年   29篇
  2008年   26篇
  2007年   23篇
  2006年   30篇
  2005年   29篇
  2004年   26篇
  2003年   14篇
  2002年   14篇
  2001年   19篇
  2000年   10篇
  1999年   9篇
  1998年   5篇
  1997年   8篇
  1996年   15篇
  1995年   17篇
  1994年   6篇
  1993年   12篇
  1992年   12篇
  1991年   12篇
  1990年   9篇
  1989年   6篇
  1988年   8篇
  1987年   4篇
  1986年   4篇
  1985年   2篇
  1984年   3篇
  1983年   8篇
  1982年   3篇
  1981年   1篇
  1980年   1篇
排序方式: 共有565条查询结果,搜索用时 15 毫秒
31.
《关于正确处理人民内部矛盾的问题》是毛泽东在社会主义建设时期最重要的理论著作之一.中共十一届三中全会以来对《关于正确处理人民内部矛盾的问题》的研究一直是学术界关注的热点问题,取得了丰硕成果.在其发表50周年之际,文章着重从近年来学术界对该文献研究的成果、研究的新视野、研究中带有争议的热点问题及研究中的不足等方面作一述评,以为纪念.  相似文献   
32.
The objective of this paper is to study the Phase I monitoring and change point estimation of autocorrelated Poisson profiles where the response values within each profile are autocorrelated. Two charts, the SLRT and the Hotelling's T2, are proposed along with an algorithm for parameter estimation. The detecting power of the proposed charts is compared using simulations in terms of the signal probability criterion. The performance of the SLRT method in estimating the change point in the regression parameters is also evaluated. Moreover, a real data example is presented to illustrate the application of the methods.  相似文献   
33.
We propose the use of signal detection theory (SDT) to evaluate the performance of both probabilistic forecasting systems and individual forecasters. The main advantage of SDT is that it provides a principled way to distinguish the response from system diagnosticity, which is defined as the ability to distinguish events that occur from those that do not. There are two challenges in applying SDT to probabilistic forecasts. First, the SDT model must handle judged probabilities rather than the conventional binary decisions. Second, the model must be able to operate in the presence of sparse data generated within the context of human forecasting systems. Our approach is to specify a model of how individual forecasts are generated from underlying representations and use Bayesian inference to estimate the underlying latent parameters. Given our estimate of the underlying representations, features of the classic SDT model, such as the receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC), follow immediately. We show how our approach allows ROC curves and AUCs to be applied to individuals within a group of forecasters, estimated as a function of time, and extended to measure differences in forecastability across different domains. Among the advantages of this method is that it depends only on the ordinal properties of the probabilistic forecasts. We conclude with a brief discussion of how this approach might facilitate decision making.  相似文献   
34.
The problem of whether seasonal decomposition should be used prior to or after aggregation of time series is quite old. We tackle the problem by using a state-space representation and the variance/covariance structure of a simplified one-component model. The variances of the estimated components in a two-series system are compared for direct and indirect approaches and also to a multivariate method. The covariance structure between the two time series is important for the relative efficiency. Indirect estimation is always best when the series are independent, but when the series or the measurement errors are negatively correlated, direct estimation may be much better in the above sense. Some covariance structures indicate that direct estimation should be used while others indicate that an indirect approach is more efficient. Signal-to-noise ratios and relative variances are used for inference.  相似文献   
35.
The scheduling problem in production management has been studied for a considerable time, and several types of software are used. A problem arises in updating the production planning, or ‘rescheduling’, when an unexpected event occurs in the shop control. Solving this problem is difficult because the implications of such events are usually impossible to forecast. To prevent this problem, we propose to manipulate a set of equivalent schedules during the short time schedule. Then, if an unexpected event prevents realization of a given schedule, it will be possible to find an equivalent one, without full rescheduling. The primary requirement is to find a formal representation of a set of schedules. This has already been explored using CPM graphs with nodes associated to a set of tasks. We propose in this paper to use an extension of such graphs, PQR trees, that represent both precedence and group constraints. We first reiterate the notion of PQR trees. We present methods to take into account date constraints in such a structure, and we give a model for the general job-shop problem.  相似文献   
36.
The most common charting procedure used for monitoring the variance of the distribution of a quality characteristic is the S control chart. As a Shewhart-type control chart, it is relatively insensitive in the quick detection of small and moderate shifts in process variance. The performance of the S chart can be improved by supplementing it with runs rules or by varying the sample size and the sampling interval. In this work, we introduce and study one-sided adaptive S control charts, supplemented or not with one powerful runs rule, for detecting increases or decreases in process variation. The properties of the proposed control schemes are obtained by using a Markov chain approach. Furthermore, a practical guidance for the choice of the most suitable control scheme is also provided.  相似文献   
37.
BOOST-PFC电路反馈环节的优化设计   总被引:1,自引:0,他引:1  
介绍了平均电流控制BOOST─PFC电路的原理,建立了电流环和电压环的小信号简化模型,讨论了双环反馈环节的设计原则和方法,提出最优设计的思想和数学模型,并以一种BOOST─PFC电路为例进行优化设计,计算模拟结果显示优化后有关指标好于优化前。  相似文献   
38.
"车站信号自动控制"这一传统的铁路特色专业课程,其课程体系日显陈旧,在教学中存在的问题越来越突出。构建新的课程体系,要重组传统内容、加强新技术内容、拓宽应用。新体系实现途径是:提高理论层次,拓宽知识面,突出主干内容教学、改革教学手段和方法。  相似文献   
39.
熊晓琳 《统计研究》2008,25(12):42-45
 本文通过改造Keynes宏观经济理论并利用省际面板数据,对加工贸易活动对地区经济增长的影响进行了分析。结果表明:加工贸易对地区经济增长有着积极和显著的影响,我国应采取措施鼓励加工贸易活动向中西部地区转移,以促进中西部地区经济增长和就业增加;我们还发现,消费增长对地区经济增长的影响超过了投资因素已成为拉动地区经济增长的重要动力。  相似文献   
40.
叙述了模式S应答信号处理的特点,包括模式S应答信号的格式和相关的目标报头检测算法、置信度判定算法以及检错纠错算法等处理算法。介绍了报头检测算法,包括视频预处理、沿提取、报头脉冲检测、参考功率值计算、交叠测试、功率一致性测试、DF验证和再触发等处理步骤。给出了报头检测算法的FPGA实现方案,采用Verilog HDL语言完成了所有功能模块的设计,并进行了电路仿真实验。仿真结果表明,该方案设计合理,能够快速准确地检测出有效报头脉冲。  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