全文获取类型
收费全文 | 2119篇 |
免费 | 156篇 |
国内免费 | 27篇 |
专业分类
电工技术 | 51篇 |
综合类 | 6篇 |
化学工业 | 526篇 |
金属工艺 | 51篇 |
机械仪表 | 96篇 |
建筑科学 | 103篇 |
矿业工程 | 6篇 |
能源动力 | 137篇 |
轻工业 | 181篇 |
水利工程 | 46篇 |
石油天然气 | 49篇 |
无线电 | 186篇 |
一般工业技术 | 378篇 |
冶金工业 | 68篇 |
原子能技术 | 20篇 |
自动化技术 | 398篇 |
出版年
2024年 | 8篇 |
2023年 | 49篇 |
2022年 | 68篇 |
2021年 | 138篇 |
2020年 | 121篇 |
2019年 | 145篇 |
2018年 | 202篇 |
2017年 | 171篇 |
2016年 | 161篇 |
2015年 | 90篇 |
2014年 | 141篇 |
2013年 | 253篇 |
2012年 | 138篇 |
2011年 | 137篇 |
2010年 | 106篇 |
2009年 | 77篇 |
2008年 | 50篇 |
2007年 | 36篇 |
2006年 | 38篇 |
2005年 | 12篇 |
2004年 | 18篇 |
2003年 | 10篇 |
2002年 | 14篇 |
2001年 | 6篇 |
2000年 | 6篇 |
1999年 | 6篇 |
1998年 | 10篇 |
1997年 | 12篇 |
1996年 | 4篇 |
1995年 | 6篇 |
1994年 | 7篇 |
1993年 | 4篇 |
1992年 | 5篇 |
1991年 | 6篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1985年 | 4篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1980年 | 2篇 |
1979年 | 5篇 |
1978年 | 2篇 |
1977年 | 4篇 |
1976年 | 2篇 |
1975年 | 3篇 |
1974年 | 2篇 |
1973年 | 2篇 |
排序方式: 共有2302条查询结果,搜索用时 6 毫秒
1.
Tourajizadeh Hami Yousefzadeh Mahdi Khalaji Ali Keymasi Bamdad Mahdi 《International Journal of Control, Automation and Systems》2022,20(5):1671-1681
International Journal of Control, Automation and Systems - In this paper, a new controllable simulator is proposed and modeled by which, experimental tests of the aircraft’s models can be... 相似文献
2.
3.
Maktabdar Oghaz Mahdi Maarof Mohd Aizaini Rohani Mohd Foad Zainal Anazida Shaid Syed Zainudeen Mohd 《Neural computing & applications》2019,31(6):1835-1853
Neural Computing and Applications - Texture analysis is devised to address the weakness of color-based image segmentation models by considering the statistical and spatial relations among the group... 相似文献
4.
The Journal of Supercomputing - Data center network virtualization is being considered as a promising technology to provide a performance guarantee for cloud computing applications. One important... 相似文献
5.
6.
DJ Conway MJ Holland RL Bailey AE Campbell OS Mahdi R Jennings E Mbena DC Mabey 《Canadian Metallurgical Quarterly》1997,65(3):1003-1006
Tumor necrosis factor alpha (TNF-alpha) may play a central role in the disease pathogenesis which occurs as a consequence of chlamydial infection. To investigate the importance of TNF-alpha gene promoter polymorphisms and TNF-alpha levels in tear fluid in scarring trachoma, a large matched-pair case-control study was performed in The Gambia. The -308A allele was present in a higher proportion of patients (28.4%) than controls (18.4%), with an increasing association for homozygotes (chi2 for trend, P = 0.032; allele frequency, 0.163 in patients and 0.099 in controls; chi2, P = 0.025). For the -238A allele, the association was similar but not significant. The disease association was highly significant when the number of either -308A or -238A sites in an individual was considered (P = 0.003). TNF-alpha promoter alleles are tightly linked to some HLA class I and II alleles, but multivariate analysis confirmed that the disease associations were independent of HLA, although a class I allele, A*6802, is also associated with disease. TNF-alpha was more frequently detected in tear samples from patients (27.6%) than from controls (15.9%), increasingly so for higher levels of detectable TNF-alpha (P = 0.015). Among patients, detectable TNF-alpha in tears was highly associated with the presence of ocular chlamydial infection (P < 0.001). The results indicate that TNF-alpha plays a major role in the tissue damage and scarring which occurs as a consequence of Chlamydia trachomatis infection. 相似文献
7.
H. Safiri M. Ahmadi G.A. Jullien W.C. Miller 《The Journal of VLSI Signal Processing》2002,31(2):91-100
A new algorithm based on Genetic Programming (GP) for the problem of optimization of Multiple constant Multiplication (MCM) by Common Subexpression Elimination(CSE) is developed. This method is used for hardware optimization for DSP systems. A solution based on Genetic Programming is shown in this paper. The performance of the technique is demonstrated in one- and multi-dimensional digital filters with constant coefficients. 相似文献
8.
9.
K. K. Gupta C. L. Lawson A. R. Ahmadi 《International journal for numerical methods in engineering》1992,33(8):1611-1623
The paper first presents the details of the development of a new six-noded plane triangular finite dynamic element. A block Lanczos algorithm is developed next for the accurate and efficient solution of the quadratic matrix eigenvalue problem associated with the finite dynamic element formulation. The resulting computer program fully exploits matrix sparsity inherent in such a discretization and proves to be most efficient for the extraction of the usually required first few roots and vectors, including repeated ones. Most importantly, the present eigenproblem solution effort is shown to be comparable to that of the corresponding finite element analysis, thereby rendering the associated dynamic element method rather attractive owing to superior convergence characteristics of such elements, presented herein. 相似文献
10.
Goodarz Ahmadi 《International Journal of Engineering Science》1985,23(1):1-25
A continuum theory for multiphase particulate suspensions in a fluid media is formulated. The generalized fundamental balance laws for the particulate phases as well as for the continuous suspending fluid phase are presented. The thermodynamics of a multiphase system is studied and the method of Lagrangian multipliers is employed to include the constraints of incompressibility of materials of the constituents and the criterion for fully saturated media. Constitutive equations are developed which include microrotational and microdilatational effects. The basic equations of motion of different phases are derived and discussed. Special considerations are given to the case of incompressible constituents. Examples of applications of the present theory to dilute suspension flows and multiphase sedimentations are also discussed. 相似文献