全文获取类型
收费全文 | 6182篇 |
免费 | 928篇 |
国内免费 | 691篇 |
专业分类
电工技术 | 501篇 |
综合类 | 544篇 |
化学工业 | 152篇 |
金属工艺 | 101篇 |
机械仪表 | 385篇 |
建筑科学 | 320篇 |
矿业工程 | 102篇 |
能源动力 | 87篇 |
轻工业 | 105篇 |
水利工程 | 154篇 |
石油天然气 | 102篇 |
武器工业 | 62篇 |
无线电 | 782篇 |
一般工业技术 | 468篇 |
冶金工业 | 109篇 |
原子能技术 | 112篇 |
自动化技术 | 3715篇 |
出版年
2024年 | 45篇 |
2023年 | 109篇 |
2022年 | 211篇 |
2021年 | 219篇 |
2020年 | 244篇 |
2019年 | 168篇 |
2018年 | 166篇 |
2017年 | 193篇 |
2016年 | 246篇 |
2015年 | 253篇 |
2014年 | 417篇 |
2013年 | 381篇 |
2012年 | 498篇 |
2011年 | 488篇 |
2010年 | 409篇 |
2009年 | 401篇 |
2008年 | 417篇 |
2007年 | 491篇 |
2006年 | 395篇 |
2005年 | 383篇 |
2004年 | 313篇 |
2003年 | 261篇 |
2002年 | 220篇 |
2001年 | 139篇 |
2000年 | 145篇 |
1999年 | 121篇 |
1998年 | 78篇 |
1997年 | 59篇 |
1996年 | 55篇 |
1995年 | 60篇 |
1994年 | 43篇 |
1993年 | 32篇 |
1992年 | 29篇 |
1991年 | 23篇 |
1990年 | 13篇 |
1989年 | 23篇 |
1988年 | 10篇 |
1987年 | 3篇 |
1986年 | 6篇 |
1985年 | 6篇 |
1984年 | 5篇 |
1983年 | 5篇 |
1982年 | 2篇 |
1980年 | 5篇 |
1979年 | 5篇 |
1975年 | 2篇 |
1972年 | 1篇 |
1963年 | 1篇 |
1961年 | 1篇 |
1951年 | 1篇 |
排序方式: 共有7801条查询结果,搜索用时 15 毫秒
1.
The performance verification of micro-CMMs is now of intense interest because of their capability to perform length measurements in three dimensions to high accuracy with low uncertainties. Currently, verification of micro-CMMs is completed in the spirit of existing specification standards, because strict adherence to these standards is often difficult. This review aims to present and discuss verification techniques available for micro-CMMs: specification standards, existing calibrated test lengths and traceability routes that can be associated with micro-CMMs. Three specification standards used in the testing of CMMs will be considered. In addition, a wide range of calibrated test lengths are reported, and any advantages and disadvantages associated with their use are discussed. It is concluded that micro-CMMs cannot yet be verified in accordance with existing specification standards. Suggestions are made for future standardisation work required to rectify these issues. 相似文献
2.
The basic methods of verifying continuous automatic belt weighers are described. A comparative analysis of these methods on the basis of experimental studies is made and ways of implementing the results in industry are recommended. 相似文献
3.
4.
5.
6.
This paper presents the main current theoretical issues in Information Retrieval. The principles of conceptual modelling, as they have emerged in the database area, are presented and their application to document modelling in order to enhance document retrieval is discussed. Finally, the main features of the MULTOS project are presented and critically reviewed confronting them with the requirements which have been identified during the general discussion on document conceptual modelling for information retrieval. 相似文献
7.
8.
9.
Sven Beyer Christian Jacobi Daniel Kröning Dirk Leinenbach Wolfgang J. Paul 《International Journal on Software Tools for Technology Transfer (STTT)》2006,8(4-5):411-430
In the verified architecture microprocessor (VAMP) project we have designed, functionally verified, and synthesized a processor
with full DLX instruction set, delayed branch, Tomasulo scheduler, maskable nested precise interrupts, pipelined fully IEEE
compatible dual precision floating point unit with variable latency, and separate instruction and data caches. The verification
has been carried out in the theorem proving system PVS. The processor has been implemented on a Xilinx FPGA.
A shorter version of this article with the title “Instantiating uninterpreted functional units and memory system: functional
verification of the VAMP” appeared in [8]. The work reported here was done while all the authors were with Saarland University. 相似文献
10.
采用传递比较法对二厘米微波衰减标准装置不确定度进行了验证。测量标准装置的重复性以组内实验标准偏差sn(A)定量表征,测量标准装置的稳定性用组间实验标准偏差sm定量表征。 相似文献