首页 | 官方网站   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   1571篇
  免费   155篇
  国内免费   13篇
工业技术   1739篇
  2024年   1篇
  2023年   35篇
  2022年   48篇
  2021年   93篇
  2020年   80篇
  2019年   103篇
  2018年   144篇
  2017年   130篇
  2016年   149篇
  2015年   85篇
  2014年   110篇
  2013年   179篇
  2012年   120篇
  2011年   88篇
  2010年   78篇
  2009年   56篇
  2008年   42篇
  2007年   32篇
  2006年   18篇
  2005年   9篇
  2004年   10篇
  2003年   10篇
  2002年   11篇
  2001年   8篇
  2000年   8篇
  1999年   4篇
  1998年   9篇
  1997年   2篇
  1996年   5篇
  1995年   12篇
  1994年   5篇
  1993年   4篇
  1992年   6篇
  1991年   5篇
  1990年   4篇
  1989年   6篇
  1988年   3篇
  1987年   2篇
  1986年   4篇
  1985年   3篇
  1984年   1篇
  1983年   3篇
  1982年   5篇
  1979年   3篇
  1975年   1篇
  1973年   2篇
  1970年   2篇
  1969年   1篇
排序方式: 共有1739条查询结果,搜索用时 15 毫秒
61.
The aim of this paper is to study a simultaneous lot-sizing and scheduling in multi-product, multi-period flexible flow shop environments. A new mixed integer programming (MIP) model is proposed to formulate the problem. The objective function includes the total cost of production, inventory, and external supply. In this study, in case of not meeting the demand of customers, this demand should be met by foreign suppliers in higher price. Due to the high computational complexity of the studied problem, a rolling horizon heuristic (RHH) and particle swarm optimization algorithm (PSO) are implemented to solve the problem. These algorithms find a feasible and near-optimal from production planning and scheduling. Additionally, Taguchi method is conducted to calibrate the parameters of the PSO algorithm and select the optimal levels of the influential factors. The computational results show that the algorithms are capable of achieving results with good quality in a reasonable time and PSO has better objective values in comparison with RHH. Also, the real case study for tile industry with real features is applied. Sensitivity analysis is used to evaluate the performance of the model.  相似文献   
62.
Multi-criteria expertness based cooperative Q-learning   总被引:2,自引:2,他引:0  
One of the most influential points in cooperative learning is the type of exchanging information. If the content of exchanging information among agents is rich, cooperation gives rise to better results. To extract proper knowledge of agents during the cooperation process, some expertness measures that assign expertness levels to the other agents are used. In this paper, a new method named Multi-Criteria Expertness based cooperative Q-learning (MCE) is proposed that utilizes all of the expertness measures and attempts to enrich the exchanging information more efficiently. In MCE, all expertness measures are considered simultaneously and collective knowledge is equal to the combination of learned knowledge by each of expertness measures. The experimental results confirm outstanding performance of the proposed method on a sample maze world and a hunter-prey problem.  相似文献   
63.
Wireless Personal Communications - Due to the widely spreading of fake news utilizing image manipulation and its bad effects, this paper investigates efficient image contents verification and...  相似文献   
64.
Liu  Can  Sadeghzadeh  Seyed Mohsen 《Catalysis Letters》2021,151(10):2807-2815
Catalysis Letters - In order to carbonize o-phenylenediamine with CO2, an effective approach was used with UV light irradiation by Sn(IV) doping DFNS (SnD) supported CdSnO3 as a catalyst...  相似文献   
65.
Journal of Applied Electrochemistry - In this paper, a novel signal-off electrochemiluminescence sensor based on a ternary nanocomposite of ruthenium nanobeads/silver nanoparticles/graphene oxide...  相似文献   
66.
67.
Clean Technologies and Environmental Policy - This paper presents a methodological approach for intelligent control of fuel cell vehicles based on traffic condition recognition. For this purpose,...  相似文献   
68.
69.
Semiconductor photocatalysts play a crucial role when it comes to environmental issues such as global warming, pollutant degradation, fuel shortage, and energy crisis. In this paper, three nanostructured compound (3‐, 4‐, and 5‐component) semiconductor materials were synthesized through a facile one‐pot hydrothermal method, and were applied as alloy photocatalysts to generate hydrogen fuel via a water photo‐splitting process. Nitrogen adsorption–desorption isotherms revealed that the synthesized materials were all mesoporous and the highest surface area was witnessed for Ag‐doped quinary photocatalyst, viz. Cd0.1Zn0.87Sn0.01Ag0.01S (CZTSS). This heterogeneous photocatalyst exhibited a maximum performance in evolving hydrogen gas. The superiority of CZTSS was justified in terms of its greater surface area, higher conduction band and its silver plasmon resonance, enhancing the light absorption at long wavelengths. Field emission scanning electron microscopy revealed a spectacular nanostructure for this photocatalyst that was comprised of nanoparticles, platelets, and microspheres attached together. Energy dispersive X‐ray (EDX) analyses of the CZTSS also proved the synthesis of the quinary photocatalyst, having different compositions in distinct zones. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
70.
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-23

京公网安备 11010802026262号