全文获取类型
收费全文 | 5175篇 |
免费 | 395篇 |
国内免费 | 19篇 |
专业分类
电工技术 | 39篇 |
综合类 | 2篇 |
化学工业 | 1076篇 |
金属工艺 | 102篇 |
机械仪表 | 117篇 |
建筑科学 | 253篇 |
矿业工程 | 10篇 |
能源动力 | 160篇 |
轻工业 | 416篇 |
水利工程 | 68篇 |
石油天然气 | 17篇 |
无线电 | 412篇 |
一般工业技术 | 1259篇 |
冶金工业 | 759篇 |
原子能技术 | 9篇 |
自动化技术 | 890篇 |
出版年
2024年 | 9篇 |
2023年 | 58篇 |
2022年 | 99篇 |
2021年 | 172篇 |
2020年 | 144篇 |
2019年 | 147篇 |
2018年 | 171篇 |
2017年 | 160篇 |
2016年 | 200篇 |
2015年 | 157篇 |
2014年 | 252篇 |
2013年 | 337篇 |
2012年 | 396篇 |
2011年 | 490篇 |
2010年 | 311篇 |
2009年 | 261篇 |
2008年 | 346篇 |
2007年 | 303篇 |
2006年 | 257篇 |
2005年 | 210篇 |
2004年 | 166篇 |
2003年 | 134篇 |
2002年 | 145篇 |
2001年 | 87篇 |
2000年 | 65篇 |
1999年 | 44篇 |
1998年 | 59篇 |
1997年 | 53篇 |
1996年 | 44篇 |
1995年 | 32篇 |
1994年 | 36篇 |
1993年 | 30篇 |
1992年 | 24篇 |
1991年 | 15篇 |
1990年 | 14篇 |
1989年 | 17篇 |
1988年 | 10篇 |
1987年 | 11篇 |
1986年 | 11篇 |
1985年 | 16篇 |
1984年 | 8篇 |
1983年 | 9篇 |
1982年 | 10篇 |
1981年 | 10篇 |
1980年 | 7篇 |
1979年 | 6篇 |
1978年 | 6篇 |
1977年 | 14篇 |
1976年 | 5篇 |
1975年 | 4篇 |
排序方式: 共有5589条查询结果,搜索用时 15 毫秒
91.
The Companion cognitive architecture supports experiments in achieving human-level intelligence. This article describes seven key design goals of Companions, relating them to properties of human reasoning and learning, and to engineering concerns raised by attempting to build large-scale cognitive systems. We summarize our experiences with Companions in two domains: test taking and game playing. 相似文献
92.
Matthew O.T. Cole Author Vitae Theeraphong Wongratanaphisan Author Vitae 《Automatica》2008,44(11):2876-2883
Model-based feedback control of vibration in flexible structures can be complicated by the possibility that interaction with an external body occurs. If not accounted for, instability or poor performance may result. In this paper, a method is proposed for achieving robust vibration control of flexible structures under contact. The method uses robust linear state feedback, coupled with a state estimation scheme utilizing contact force measurement. Uncertain contact characteristics are modelled by a sector-bounded non-linear function, such that state feedback gains can be synthesized using a matrix inequality formulation of the Popov stability criterion. A separation theorem is used to establish a robust H2 cost bound for the closed loop system. Experimental results from a multi-mode flexible structure testbed confirm that vibration attenuation and stability can be maintained over a broad range of contact characteristics, in terms of compliance and clearance. 相似文献
93.
Xuejie Gao Xiaofei Yang Ming Jiang Matthew Zheng Yang Zhao Ruying Li Wenfeng Ren Huan Huang Runcang Sun Jiantao Wang Chandra Veer Singh Xueliang Sun 《Advanced functional materials》2023,33(7):2209715
All-solid-state Li batteries (ASSLBs) with solid-polymer electrolytes are considered promising battery systems to achieve improved safety and high energy density. However, Li dendrite formation at the Li anode under high charging current density/capacity has limited their development. To tackle the issue, Li-metal alloying has been proposed as an alternative strategy to suppress Li dendrite growth in ASSLBs. One drawback of alloying is the relatively lower operating cell voltages, which will inevitably lower energy density compared to cells with pure Li anode. Herein, a Li-rich Li13In3 alloy electrode (LiRLIA) is proposed, where the Li13In3 alloy scaffold guides Li nucleation and hinders Li dendrite formation. Meanwhile, the free Li can recover Li's potential and facilitate fast charge transfer kinetics to realize high-energy-density ASSLBs. Benefitting from the stronger adsorption energy and lower diffusion energy barrier of Li on a Li13In3 substrate, Li prefers to deposit in the 3D Li13In3 scaffold selectively. Therefore, the Li–Li symmetric cell constructed with LiRLIA can operate at a high current density/capacity of 5 mA cm−2/5 mAh cm−2 for almost 1000 h. 相似文献
94.
95.
Zahid Farzana Tanveer Awais Kuo Matthew M. Y. Sinha Roopak 《Journal of Intelligent Manufacturing》2022,33(6):1603-1638
Journal of Intelligent Manufacturing - The requirements engineering of Industrial Cyber-Physical Systems is extremely challenging due to large system sizes, component heterogeneity, involvement of... 相似文献
96.
Shiwei?Zhao T.?Matthew?EvansEmail authorView authors OrcID profile Xiaowen?Zhou Shuai?Zhou 《Granular Matter》2017,19(1):11
Temperature change, as a common kind of internal perturbation performed on granular materials, has a significant effect on the bulk properties of granular materials. However, few studies on thermally-induced shakedown under a long-term thermal cycling were reported. In this work, the discrete element method was used to give insight into the thermally-induced shakedown on the fabric and stress states within non-cohesive, frictional granular assemblies. Assemblies were submitted to thermal cycling at a stationary boundary condition after experiencing a one-dimensional compression. Evolution of coordination number, entropy and anisotropy was investigated as well as boundary forces and contact forces. At the same time, effects of the heating rate, the initial vertical load and the magnitude of temperature change were examined. It demonstrates that thermal cycling induces a significant force relaxation within granular materials, while the corresponding granular fabric has a small change. In addition, the entropy and anisotropy decreases with thermal cycling. Moreover, the initial vertical load can constrain the development of thermally-induced fabric change, thereby limiting force relaxation to some degree. Both high heating rate and larger magnitudes of temperature change contribute to more significant force relaxation. However, they cause smaller fabric changes even though they provide larger perturbations. 相似文献
97.
98.
Self‐Sealing Porous Silicon‐Calcium Silicate Core–Shell Nanoparticles for Targeted siRNA Delivery to the Injured Brain 下载免费PDF全文
99.
Duyao Zhang Shoujin Sun Dong Qiu Mark A. Gibson Matthew S. Dargusch Milan Brandt Ma Qian Mark Easton 《Advanced Engineering Materials》2018,20(5)
100.
Karen M. Feigh Matthew J. Miller Raunak P. Bhattacharyya Minyue Ma Samantha Krening Yosef Razin 《Theoretical Issues in Ergonomics Science》2018,19(4):389-405
Human factors practitioners (HFPs) play many different roles in the design, creation, operation and maintenance of engineered systems. Less well known are the methods which are aimed at helping with the early stages of design, which are more systems-oriented and often involve questions of the concept of operation in which the engineered system will be fielded. Emerging from the field of cognitive engineering, these methods, including simulation, cognitive work analysis, cognitive task analyses and hierarchical task analysis, will be important as autonomous systems become increasingly capable. Even the most capable systems will continue to interact with humans, and it is at these interfaces between humans and engineered systems that HFP will continue to be needed. This paper describes recent work to leverage these methods to inform concepts of operation in aviation and space, machine learning algorithms and goal-oriented human–machine collaboration. 相似文献