全文获取类型
收费全文 | 3215篇 |
免费 | 198篇 |
国内免费 | 15篇 |
专业分类
电工技术 | 32篇 |
综合类 | 10篇 |
化学工业 | 1086篇 |
金属工艺 | 56篇 |
机械仪表 | 60篇 |
建筑科学 | 57篇 |
矿业工程 | 12篇 |
能源动力 | 146篇 |
轻工业 | 161篇 |
水利工程 | 16篇 |
石油天然气 | 12篇 |
武器工业 | 1篇 |
无线电 | 298篇 |
一般工业技术 | 816篇 |
冶金工业 | 137篇 |
原子能技术 | 51篇 |
自动化技术 | 477篇 |
出版年
2023年 | 51篇 |
2022年 | 172篇 |
2021年 | 173篇 |
2020年 | 67篇 |
2019年 | 79篇 |
2018年 | 100篇 |
2017年 | 103篇 |
2016年 | 121篇 |
2015年 | 98篇 |
2014年 | 169篇 |
2013年 | 252篇 |
2012年 | 192篇 |
2011年 | 235篇 |
2010年 | 169篇 |
2009年 | 164篇 |
2008年 | 176篇 |
2007年 | 137篇 |
2006年 | 103篇 |
2005年 | 100篇 |
2004年 | 87篇 |
2003年 | 89篇 |
2002年 | 97篇 |
2001年 | 62篇 |
2000年 | 49篇 |
1999年 | 44篇 |
1998年 | 26篇 |
1997年 | 33篇 |
1996年 | 32篇 |
1995年 | 24篇 |
1994年 | 27篇 |
1993年 | 18篇 |
1992年 | 22篇 |
1991年 | 9篇 |
1990年 | 21篇 |
1989年 | 10篇 |
1988年 | 5篇 |
1987年 | 9篇 |
1986年 | 5篇 |
1985年 | 7篇 |
1984年 | 14篇 |
1983年 | 8篇 |
1982年 | 7篇 |
1981年 | 7篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1978年 | 4篇 |
1976年 | 4篇 |
1972年 | 4篇 |
1971年 | 4篇 |
1965年 | 3篇 |
排序方式: 共有3428条查询结果,搜索用时 31 毫秒
71.
Hrachya Astsatryan Vladimir Sahakyan Yuri Shoukouryan Michel Daydé Aurelie Hurault Ronan Guivarch Harutyun Terzyan Levon Hovhannisyan 《Journal of Grid Computing》2013,11(2):239-248
Scientific research is becoming increasingly dependent on the large-scale analysis of data using distributed computing infrastructures (Grid, cloud, GPU, etc.). Scientific computing (Petitet et al. 1999) aims at constructing mathematical models and numerical solution techniques for solving problems arising in science and engineering. In this paper, we describe the services of an integrated portal based on the P-Grade (Parallel Grid Run-time and Application Development Environment) portal (http://www.p-grade.hu) that enables the solution of large-scale linear systems of equations using direct solvers, makes easier the use of parallel block iterative algorithm and provides an interface for parallel decision making algorithms. The ultimate goal is to develop a single sign on integrated multi-service environment providing an easy access to different kind of mathematical calculations and algorithms to be performed on hybrid distributed computing infrastructures combining the benefits of large clusters, Grid or cloud, when needed. 相似文献
72.
Vladimir Yanovsky 《Information Processing Letters》2008,108(1):41-44
Dotted interval graphs were introduced by Aumann et al. [Y. Aumann, M. Lewenstein, O. Melamud, R. Pinter, Z. Yakhini, Dotted interval graphs and high throughput genotyping, in: ACM-SIAM Symposium on Discrete Algorithms, SODA 2005, pp. 339-348] as a generalization of interval graphs. The problem of coloring these graphs found application in high-throughput genotyping. Jiang [M. Jiang, Approximating minimum coloring and maximum independent set in dotted interval graphs, Information Processing Letters 98 (2006) 29-33] improves the approximation ratio of Aumann et al. [Y. Aumann, M. Lewenstein, O. Melamud, R. Pinter, Z. Yakhini, Dotted interval graphs and high throughput genotyping, in: ACM-SIAM Symposium on Discrete Algorithms, SODA 2005, pp. 339-348]. In this work we improve the approximation ratio of Jiang [M. Jiang, Approximating minimum coloring and maximum independent set in dotted interval graphs, Information Processing Letters 98 (2006) 29-33] and Aumann et al. [Y. Aumann, M. Lewenstein, O. Melamud, R. Pinter, Z. Yakhini, Dotted interval graphs and high throughput genotyping, in: ACM-SIAM Symposium on Discrete Algorithms, SODA 2005, pp. 339-348]. In the exposition we develop a generalization of the problem of finding the maximum number of non-attacking queens on a triangle. 相似文献
73.
74.
Boosted Bayesian network classifiers 总被引:2,自引:0,他引:2
The use of Bayesian networks for classification problems has received a significant amount of recent attention. Although computationally
efficient, the standard maximum likelihood learning method tends to be suboptimal due to the mismatch between its optimization
criteria (data likelihood) and the actual goal of classification (label prediction accuracy). Recent approaches to optimizing
classification performance during parameter or structure learning show promise, but lack the favorable computational properties
of maximum likelihood learning. In this paper we present boosted Bayesian network classifiers, a framework to combine discriminative
data-weighting with generative training of intermediate models. We show that boosted Bayesian network classifiers encompass
the basic generative models in isolation, but improve their classification performance when the model structure is suboptimal.
We also demonstrate that structure learning is beneficial in the construction of boosted Bayesian network classifiers. On
a large suite of benchmark data-sets, this approach outperforms generative graphical models such as naive Bayes and TAN in
classification accuracy. Boosted Bayesian network classifiers have comparable or better performance in comparison to other
discriminatively trained graphical models including ELR and BNC. Furthermore, boosted Bayesian networks require significantly
less training time than the ELR and BNC algorithms. 相似文献
75.
Eugene Pozhidaev Vladimir Chigrinov Gurumurthy Hegde Peizhi Xu 《Journal of the Society for Information Display》2009,17(1):53-59
Abstract— Multistable electro‐optical modes exist under certain conditions in ferroelectric liquid‐crystal (FLC) cells, which means that any light‐transmission level can be memorized after the driving voltage is switched off. The multistability is responsible for three new electro‐optical modes with different shapes of the gray‐scale curve that can be either S‐shaped (double or single dependent upon the applied‐voltage pulse sequence and boundary conditions) or V‐shaped dependent upon boundary conditions and FLC cell parameters. The origin of these modes will be described. 相似文献
76.
Zambia Consolidated Copper Mines Ltd. (ZCCM) is planning a substantial increase in ore production in several of their underground mines on the Zambian Copperbelt over the next 10 years. The future production strategy is based on development of productive and economic mining methods through the application of mechanization and backfilling. Mechanization is designed to provide the production capability and the backfilling is designed to reduce water inflow into the mines. A similar trend can be seen in world-wide changes in mining methods from open stoping and sub-level caving to cut-and-fill stoping. Backfill is being employed worldwide, including in Australia, Canada, Sweden, Latin America, Zambia, and the U.S.A. Plans for backfill mining methods are underway for future operations in Chile, Canada, Zambia, and Mexico. The principal reasons for these changes in mining methods are twofold: ? Increased ore recovery, and ? Decreased environmental impact. The main difference in the environmental impacts between mining with sub-level caving or open stoping and mining with backfilling methods is the reduction in subsidence or the potential for subsidence. Backfilling reduces ground movements in the rock overlying and adjacent to mine openings as well as subsidence at the surface. Reduced ground movement decreases the number and size of fracture-controlled hydraulic flow paths into a mine and, thereby, the impact of mining on surface and ground water resources. This paper deals with: 1) The impacts caused by open stoping and sub-level caving in comparison to backfilling methods; 2) The approximate impact of backfill on dewatering strategies, and; 3) The environmental benefits of backfill mining. The differences in mine drainage strategies are supported by case histories from various mines. 相似文献
77.
Composite Materials Based on Shape‐Memory Ti2NiCu Alloy for Frontier Micro‐ and Nanomechanical Applications
下载免费PDF全文
![点击此处可从《Advanced Engineering Materials》网站下载免费的PDF全文](/ch/ext_images/free.gif)
78.
Chung Yen Ang Si Yu Tan Cathleen Teh Jia Min Lee Mun Fei Eddy Wong Qiuyu Qu Li Qing Poh Menghuan Li Yuanyuan Zhang Vladimir Korzh Yanli Zhao 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(7)
Responsive nanomaterials have emerged as promising candidates as drug delivery vehicles in order to address biomedical diseases such as cancer. In this work, polymer‐based responsive nanoparticles prepared by a supramolecular approach are loaded with doxorubicin (DOX) for the cancer therapy. The nanoparticles contain disulfide bonds within the polymer network, allowing the release of the DOX payload in a reducing environment within the endoplasm of cancer cells. In addition, the loaded drug can also be released under acidic environment. In vitro anticancer studies using redox and pH dual responsive nanoparticles show excellent performance in inducing cell death and apoptosis. Zebrafish larvae treated with DOX‐loaded nanoparticles exhibit an improved viability as compared with the cases treated with free DOX by the end of a 3 d treatment. Confocal imaging is utilized to provide the daily assessment of tumor size on zebrafish larva models treated with DOX‐loaded nanoparticles, presenting sustainable reduction of tumor. This work demonstrates the development of functional nanoparticles with dual responsive properties for both in vitro and in vivo drug delivery in the cancer therapy. 相似文献
79.
80.