全文获取类型
收费全文 | 1062篇 |
免费 | 47篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 12篇 |
综合类 | 6篇 |
化学工业 | 252篇 |
金属工艺 | 21篇 |
机械仪表 | 25篇 |
建筑科学 | 46篇 |
能源动力 | 61篇 |
轻工业 | 113篇 |
水利工程 | 12篇 |
石油天然气 | 16篇 |
无线电 | 106篇 |
一般工业技术 | 190篇 |
冶金工业 | 72篇 |
原子能技术 | 5篇 |
自动化技术 | 173篇 |
出版年
2024年 | 3篇 |
2023年 | 28篇 |
2022年 | 56篇 |
2021年 | 65篇 |
2020年 | 51篇 |
2019年 | 44篇 |
2018年 | 49篇 |
2017年 | 46篇 |
2016年 | 51篇 |
2015年 | 32篇 |
2014年 | 45篇 |
2013年 | 90篇 |
2012年 | 44篇 |
2011年 | 73篇 |
2010年 | 40篇 |
2009年 | 40篇 |
2008年 | 39篇 |
2007年 | 31篇 |
2006年 | 28篇 |
2005年 | 32篇 |
2004年 | 28篇 |
2003年 | 17篇 |
2002年 | 6篇 |
2001年 | 8篇 |
2000年 | 8篇 |
1999年 | 9篇 |
1998年 | 23篇 |
1997年 | 13篇 |
1996年 | 13篇 |
1995年 | 10篇 |
1994年 | 9篇 |
1993年 | 7篇 |
1992年 | 8篇 |
1991年 | 4篇 |
1990年 | 2篇 |
1989年 | 4篇 |
1988年 | 6篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1985年 | 7篇 |
1984年 | 6篇 |
1983年 | 5篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1973年 | 3篇 |
1970年 | 3篇 |
1967年 | 1篇 |
排序方式: 共有1110条查询结果,搜索用时 15 毫秒
1.
Group Decision Making by Using Incomplete Fuzzy Preference Relations Based on T‐Consistency and the Order Consistency
下载免费PDF全文
![点击此处可从《国际智能系统杂志》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Samina Ashraf 《国际智能系统杂志》2015,30(2):120-143
The existing group decision making techniques may not satisfy the order consistency for aggregation in some cases. The algorithm proposed in this paper overcomes the weaknesses of the existing techniques. The method determines the unknown preferences for group decision making in such a manner that the resulting matrix is T‐consistent and order consistent simultaneously. 相似文献
2.
Shank S. Kulkarni Kyoo Sil Choi Wenbin Kuang Nalini Menon Bernice Mills Ayoub Soulami Kevin Simmons 《International Journal of Hydrogen Energy》2021,46(36):19001-19022
The use of hydrogen as a fuel is increasing exponentially, and the most economical way to store and transport hydrogen for fuel use is as a high-pressure gas. Polymers are widely used for hydrogen distribution and storage systems because they are chemically inert towards hydrogen. However, when exposed to high-pressure hydrogen, some hydrogen diffuses through polymers and occupies the preexisting cavities inside the material. Upon depressurization, the hydrogen trapped inside polymer cavities can cause blistering or cracking by expanding these cavities. A continuum mechanics–based deformation model was deployed to predict the stress distribution and damage propagation while the polymer undergoes depressurization after high-pressure hydrogen exposure. The effects of cavity size, cavity location, and pressure inside the cavity on damage initiation and evolution inside the polymer were studied. The stress and damage evolution in the presence of multiple cavities was also studied, because interaction among cavities alters the damage and stress field. It was found that all these factors significantly change the stress state in the polymer, resulting in different paths for damage propagation. The effect of adding carbon black filler particles and plasticizer on the damage was also studied. It was found that damage tolerance of the polymer increases drastically with the addition of carbon black fillers, but decreases with the addition of the plasticizer. 相似文献
3.
Ashraf Ayoub 《Computers & Structures》2003,81(7):411-421
This paper presents an inelastic element for the analysis of beams on foundations. The element is derived from a two-field mixed formulation with independent approximation of forces and displacements. The state determination algorithm for the implementation of the element in a general purpose nonlinear finite element analysis program is presented and its stability characteristics are discussed. Numerical studies are performed to compare the model with the classical displacement formulation. The studies confirm the superiority of the proposed model in describing the inelastic behavior of beams on foundations. 相似文献
4.
This note describes a method for measurement of isokinetic strength for prediction of manual materials handling capacity of individuals. The apparatus used in this methodology and measurement technique are illustrated in detail. 相似文献
5.
We introduce an effective computer aided learning visual tool (CALVT) to teach graph-based applications. We present the robot motion planning problem as an example of such applications. The proposed tool can be used to simulate and/or further to implement practical systems in different areas of computer science such as graphics, computational geometry, robotics and networking. In the robot motion planning example, CALVT enables users to setup the working environment by creating obstacles and a robot of different shapes, specifying starting and goal positions, and setting other path or environment parameters from a user-friendly interface. The path planning system involves several phases. Each of these modules is complex and therefore we provide the possibility of visualizing graphically the output of each phase. Based on our experience, this tool has been an effective one in classroom teaching. It not only cuts down, significantly, on the instructor’s time and effort but also motivates senior/graduate students to pursue work in this specific area of research. 相似文献
6.
Ashraf Bastawros Abhijit Chandra Yongjin Guo Bo Yan 《Journal of Electronic Materials》2002,31(10):1022-1031
The role of a porous pad in controlling material-removal rate (MRR) during the chemical-mechanical planarization (CMP) process
has been studied numerically. The numerical results are used to develop a phenomenological model that correlates the forces
on each individual abrasive particle to the applied nominal pressure. The model provides a physical explanation for the experimentally
observed domains of pressure-dependent MRR, where the pad deformation controls the load sharing between active-abrasive particles
and direct pad-wafer contact. The predicted correlations between MRR and slurry characteristics, i.e., particle size and concentration,
are in agreement with experimentally measured trends reported by Ouma1 and Izumitani.2 相似文献
7.
The main objective of this paper is to generate ergonomic software that can be used in the design and evaluation of manual materials handling tasks so as to minimize the risk of injury. Specifically, this study is aimed at developing a microcomputer-based model for the design of frequent manual lifting tasks based ont he concept of job saverity index. The microcomputer-based software package is intended to be used by non-experts in the field of MMH. Possible engineering and administrative controls are implemented in the software in case if human lifting abilities are exceeded. The software was written in AutoLISP for the IBM personal computer. The knowledge base of the software is built upon a set of two models which were developed in the present study. The models were based on 2,736 observations. 相似文献
8.
A study of radiation effects on various types of glasses, dielectric optical coatings, cemented optics and fiber was undertaken with a view to select them for extreme radiation environments. Samples were exposed to different radiation doses in the Pakistan Research Reactor-I (PARR-I) for neutron and Cobalt 60 source for gamma irradiation. Transmissions were measured before and after irradiation. The dielectric coatings were subjected to additional tests (adhesion, abrasion and humidity, etc.) as per MIL-M-13508C and MIL-C-675C. All 15 glasses studied showed varying amounts of transmission loss as expected, with negligible degradation for three types. Recovery of transmissions with time/ageing was also studied, with more or less complete recovery with temperature annealing. A faster bleaching of darkened/brown glasses was achieved by using UV lamps or UV laser. The dielectric coatings (HR, AR) and one of the two commercial optical cements showed excellent resistance to neutrons and gamma radiations, and could be good candidates for the fabrication and utilization of optical components in extreme radiation environments. The data allowed several Chinese glasses to be studied for the first time. 相似文献
9.
10.
A typical or conventional workstation for a repetitive drill press operation was evaluated and subsequently redesigned by incorporating the concepts and principles of work design and ergonomics. The production task comprised of drilling four holes on a prepared steel plate. A methods–time measurement (MTM) analysis was conducted to eliminate unnecessary motions and improve the necessary (work) motions involved in task performance. The specific features of the redesigned workstation were specially designed equipment (jig, fixture, etc.), a suitable adjustable chair, proper work height, a placement of tools/equipment within reach envelope, and a comprehensive operator training method. An experimental investigation was conducted to evaluate and test the redesigned workstation in terms of operator productivity (production quantity and quality output) and satisfaction. The increases in quantity (number of holes drilled) and quality (number of good holes drilled) output were 22 and 50%, respectively, for the redesigned workstation compared to the typical or conventional workstation. The high improvement in quality output (50%) could be attributed to the improved design of the jig and fixture and the comprehensive operator training method, which emphasizes the quality aspect of production output. The improvement in operator satisfaction (scores) were highly significant. This investigation has demonstrated the beneficial effect of a combined work design and ergonomics approach, especially for the redesign of a workstation for a repetitive drill press operation. © 2007 Wiley Periodicals, Inc. Hum Factors Man 17: 395–410, 2007. 相似文献