全文获取类型
收费全文 | 11278篇 |
免费 | 421篇 |
国内免费 | 558篇 |
专业分类
电工技术 | 381篇 |
综合类 | 358篇 |
化学工业 | 1132篇 |
金属工艺 | 641篇 |
机械仪表 | 1481篇 |
建筑科学 | 427篇 |
矿业工程 | 346篇 |
能源动力 | 809篇 |
轻工业 | 209篇 |
水利工程 | 84篇 |
石油天然气 | 195篇 |
武器工业 | 74篇 |
无线电 | 746篇 |
一般工业技术 | 841篇 |
冶金工业 | 493篇 |
原子能技术 | 137篇 |
自动化技术 | 3903篇 |
出版年
2025年 | 50篇 |
2024年 | 104篇 |
2023年 | 137篇 |
2022年 | 197篇 |
2021年 | 274篇 |
2020年 | 255篇 |
2019年 | 251篇 |
2018年 | 294篇 |
2017年 | 375篇 |
2016年 | 404篇 |
2015年 | 503篇 |
2014年 | 712篇 |
2013年 | 813篇 |
2012年 | 827篇 |
2011年 | 990篇 |
2010年 | 591篇 |
2009年 | 683篇 |
2008年 | 622篇 |
2007年 | 681篇 |
2006年 | 593篇 |
2005年 | 527篇 |
2004年 | 376篇 |
2003年 | 363篇 |
2002年 | 284篇 |
2001年 | 176篇 |
2000年 | 171篇 |
1999年 | 166篇 |
1998年 | 138篇 |
1997年 | 113篇 |
1996年 | 106篇 |
1995年 | 86篇 |
1994年 | 95篇 |
1993年 | 59篇 |
1992年 | 48篇 |
1991年 | 32篇 |
1990年 | 31篇 |
1989年 | 26篇 |
1988年 | 29篇 |
1987年 | 8篇 |
1986年 | 11篇 |
1985年 | 12篇 |
1984年 | 7篇 |
1983年 | 8篇 |
1982年 | 3篇 |
1981年 | 7篇 |
1979年 | 4篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1975年 | 5篇 |
1973年 | 3篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
Response surface methodology is often used by researchers in different fields to determine the optimum values for controlled variables to maximize or minimize the response variables. Either maximization or minimization might be necessary depending on the response property. For example, if the response variable represents the yield of a process, maximization could be necessary; on the other hand, if the response variable is the biological oxygen demand (BOD) of an effluent the aim would definitely be minimization
Response surface methodology can be used two ways. It can be applied to the full-scale production or it can be scaled to a laboratory or the pilot plant. When applied to the full-scale production, the method is known as evolutionary operation (EVOP). EVOP is the continuous optimization of a process. The optimum conditions in a production plant can change depending on many factors such as raw material, ambient temperature, and equipment wear. Therefore, controlled variables should be optimized continuously to keep the response variable as close as possible to the maximum or minimum value. Hence, controlled variables are systematically changed around a center point to depict any shift of the response variable from the extreme. A thorough discussion of EVOP is given by Box, Evolutionary Operation: A Method for Increasing Industrial Productivity, Appl. Statist., 6, 81-101 (1957). 相似文献
Response surface methodology can be used two ways. It can be applied to the full-scale production or it can be scaled to a laboratory or the pilot plant. When applied to the full-scale production, the method is known as evolutionary operation (EVOP). EVOP is the continuous optimization of a process. The optimum conditions in a production plant can change depending on many factors such as raw material, ambient temperature, and equipment wear. Therefore, controlled variables should be optimized continuously to keep the response variable as close as possible to the maximum or minimum value. Hence, controlled variables are systematically changed around a center point to depict any shift of the response variable from the extreme. A thorough discussion of EVOP is given by Box, Evolutionary Operation: A Method for Increasing Industrial Productivity, Appl. Statist., 6, 81-101 (1957). 相似文献
2.
3.
A decision aid for scheduling production in glass fiber manufacturing industry is described. The methodology combines a linear programming (LP) optimization model with a heuristic model. The LP model determines production goals; the heuristic model then uses the LP output to incorporate system-specific constraints in developing processing sequences. 相似文献
4.
李文棣 《网络安全技术与应用》2013,(11):135-136
信息总量、网络浏览人数以及人们对网络享受需求的增加,促使着信息制作水平的提高,制作水平的提高在给人们带来了更好的视觉和听觉享受的同时,也对计算机的硬件系统提出了巨大的考验.计算机内存作为计算机硬件系统的重要组成部分,能否对内存做好合理的划分,对计算机的体验具有重要的意义. 相似文献
5.
谢树新 《数字社区&智能家居》2009,(17)
已有文献中的支持向量机SMO算法推导过程计算复杂,该文给出一个简洁推导。整个推导过程没有复杂的计算,除了误差函数外,不需引入其它中间变量。 相似文献
6.
在众多彩色图像滤波算法中,矢量中值滤波算法应用最为广泛,但VMF算法在处理每一像素时,计算复杂度较高,这就限制了它在一些领域中(例如实时系统)的应用.在保留VMF算法优点的前提下,通过数据的重用,降低计算的复杂度.实验结果表明,一定程度的数据重用能有效提高算法的运行效率. 相似文献
7.
This paper proposes an indirect method for the identification of moving vehicular parameters using the dynamic responses of the vehicle. The moving vehicle is modelled as 2-DOF system with 5 parameters and 4-DOF system with 12 parameters, respectively. Finite element method is used to establish the equation of the coupled bridge–vehicle system. The dynamic responses of the system are calculated by Newmark direct integration method. The parameter identification problem is transformed into an optimization problem by minimizing errors between the calculated dynamic responses of the moving vehicle and those of the simulated measured responses. Glowworm swarm optimization algorithm (GSO) is used to solve the objective function of the optimization problem. A local search method is introduced into the movement phase of GSO to enhance the accuracy and convergence rate of the algorithm. Several test cases are carried out to verify the efficiency of the proposed method and the results show that the vehicular parameters can be identified precisely with the present method and it is not sensitive to artificial measurement noise. 相似文献
8.
The paper presents a formal methodology for the hull form optimization in calm and rough water using wash waves and selected dynamic responses, respectively. Parametric hull form modeling is used to generate the variant hull forms with some of the form parameters modified, which are evaluated in the optimization scheme based on evolutionary strategies. Rankine-source panel method and strip theories are used for the hydrodynamic evaluation. The methodology is implemented in the optimization of a double-chine, planing hull form. Furthermore, a dual-stage optimization strategy is applied on a modern fast displacement ferry. The effect of the selected optimization parameters is presented and discussed. 相似文献
9.
10.
Sangmun Shin Nguyen Khoa Viet Truong Byung Rae Cho Sung Hoon Hong 《Computers & Industrial Engineering》2011
Robust design (RD) and tolerance design (TD) have received much attention from researchers and practitioners for more than two decades, and a number of methodologies for modeling and optimizing the RD and TD processes have been studied. However, there is ample room for improvement. Because most existing research considers RD and TD as separate research fields, the primary objective of this paper is to develop a sequential robust–tolerance design method to jointly determine the best factor settings and the closed-form solutions for the optimal specification limits. We then apply the proposed method to a destructive quality characteristic. Finally, a case study and sensitivity analyses are performed for verification purposes, and further studies are discussed. 相似文献