全文获取类型
收费全文 | 9334篇 |
免费 | 746篇 |
国内免费 | 187篇 |
专业分类
系统科学 | 1205篇 |
丛书文集 | 89篇 |
教育与普及 | 67篇 |
理论与方法论 | 286篇 |
现状及发展 | 879篇 |
研究方法 | 20篇 |
综合类 | 7721篇 |
出版年
2024年 | 19篇 |
2023年 | 42篇 |
2022年 | 50篇 |
2021年 | 56篇 |
2020年 | 44篇 |
2019年 | 18篇 |
2018年 | 743篇 |
2017年 | 764篇 |
2016年 | 455篇 |
2015年 | 100篇 |
2014年 | 108篇 |
2013年 | 106篇 |
2012年 | 371篇 |
2011年 | 1078篇 |
2010年 | 930篇 |
2009年 | 607篇 |
2008年 | 663篇 |
2007年 | 893篇 |
2006年 | 150篇 |
2005年 | 174篇 |
2004年 | 244篇 |
2003年 | 290篇 |
2002年 | 224篇 |
2001年 | 180篇 |
2000年 | 118篇 |
1999年 | 253篇 |
1998年 | 212篇 |
1997年 | 175篇 |
1996年 | 146篇 |
1995年 | 155篇 |
1994年 | 144篇 |
1993年 | 112篇 |
1992年 | 122篇 |
1991年 | 113篇 |
1990年 | 112篇 |
1989年 | 105篇 |
1988年 | 82篇 |
1987年 | 65篇 |
1986年 | 28篇 |
1985年 | 14篇 |
1984年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
FROM MANUFACTURING SCHEDULING TO SUPPLY CHAIN COORDINATION:THE CONTROL OF COMPLEXITY AND UNCERTAINTY
Peter B.LUH 《系统科学与系统工程学报(英文版)》2003,12(3):279-297
With time-based competition and rapid technology advancements, effective manufacturingscheduling and supply chain coordination are critical to quickly respond to changing marketconditions. These problems, however, are difficult in view of inherent complexity and variousuncertainties involved. Based on a series of results by the authors, decomposition and coordination byusing Lagrangian relaxation is identified in this paper as an effective way to control complexity anduncertainty.A manufacturing scheduling problem is first formulated within the job shop context withuncertain order arrivals, processing times, due dates, and part priorities as a separable optimizationproblem. A solution methodology that combines Lagrangian relaxation, stochastic dynamicprogramming, and heuristics is developed. Method improvements to effectively solve large problemsare also highlighted. To extend manufacturing scheduling within a factory to coordinate autonomicmembers across chains of suppliers, a decentralized supply chai 相似文献
42.
以砌体结构为例,阐明在工程量计算中应正确应用统筹法,并得出了砌体工程量计算的统筹公式。 相似文献
43.
新课程背景下教师综合素质能力调查研究 总被引:1,自引:0,他引:1
课程改革中,教师的素质与能力能否适应新课程的要求,教师需要哪些方面的学习与研究,才能适合新课程。课题组针对西安市部分中学教师的调研,发现教育教学中还存在着问题,并对教师综合素质与能力的提高做了一些探究。 相似文献
44.
本文介绍使用单片机代替交流电梯控制系统中传统使用的继电器控制系统,实现了对层呼信号或指令信号登记、自动定时关门(门联锁)、自动检测定向、顺向载车、停站和自动开门……等十多种功能,提高了运行的平稳可靠、灵活、平层准确以及可调速度、方便维修保养等有关性能. 相似文献
45.
Shape skeletonization (i.e., medial axis extraction) is powerful in many visual computing applications, such as pattern recognition, object segmentation, registration, and animation. In this paper, the authors expand the use of diffusion equations combined with distance field information to approximate medial axes of arbitrary 3D differential properties. It offers an alternative solids represented by polygonal meshes based on their but natural way for medial axis extraction for commonly used 3D polygonal models. By solving the PDE along time axis, this system can not only quickly extract diffusion-based medial axes of input meshes, but also allow users to visualize the extraction process at each time step. In addition, the proposed model provides users a set of manipulation toolkits to sculpt extracted medial axes, then use diffusion-based techniques to recover corresponding deformed shapes according to the original input datasets. This skeleton-based shape manipulation offers a fast and easy way for animation and deformation of complicated mesh objects. 相似文献
46.
提出了一种虚拟现实应用于电子商务的新方法,这种方法能对目前电子商务普遍性问题进行解决,但虚拟技术正处在发展阶段,本方法还有很大的改进空间. 相似文献
47.
LED显示屏现在市面上非常流行,本文从实验块的硬件电路出发,讨论了LED点阵显示屏硬件电路的制作,并对实验块进行了成功运行。 相似文献
48.
Systemic Intervention in a University Department: Reflections on Arrested Action Research 总被引:1,自引:1,他引:0
Don Houston 《Systemic Practice and Action Research》2008,21(2):133-152
This paper reflects on my experience as an insider researcher attempting to use critical systems ideas and practices to promote
quality improvement in a university engineering department. Reflection is a key part of learning. This paper is intended to
contribute to critically, self-reflective learning for the community of systems practitioners. These reflections on my questions
about participation, ethics, politics of process, and the choices and actions resulting from them may help others to formulate
their own. The complexity of systems practice places substantial demands on the researcher, particularly in the case of insider,
practitioner research. Nevertheless, the exploration of critical systems approaches to critique boundaries and structure ‘problems’
in the core aspects of higher education in locally meaningful ways should continue. While demanding, it still can work to
promote learning about authentic quality. 相似文献
49.
50.
Li XIE Lihua XIE 《系统科学与复杂性》2007,20(2):262-272
We consider the stability of a random Riccati equation with a Markovian binary jump coefficient. More specifically, we are concerned with the boundedness of the solution of a random Riccati difference equation arising from Kalman filtering with measurement losses. A sufficient condition for the peak covariance stability is obtained which has a simpler form and is shown to be less conservative in some cases than a very recent result in existing literature. Furthermore, we show that a known sufficient condition is also necessary when the observability index equals one. 相似文献