全文获取类型
收费全文 | 128篇 |
免费 | 16篇 |
国内免费 | 5篇 |
专业分类
电工技术 | 30篇 |
综合类 | 7篇 |
化学工业 | 31篇 |
机械仪表 | 4篇 |
轻工业 | 6篇 |
水利工程 | 1篇 |
石油天然气 | 1篇 |
无线电 | 27篇 |
一般工业技术 | 4篇 |
冶金工业 | 3篇 |
自动化技术 | 35篇 |
出版年
2022年 | 7篇 |
2021年 | 11篇 |
2020年 | 6篇 |
2019年 | 4篇 |
2018年 | 1篇 |
2016年 | 3篇 |
2015年 | 8篇 |
2014年 | 13篇 |
2013年 | 18篇 |
2012年 | 8篇 |
2011年 | 19篇 |
2010年 | 16篇 |
2009年 | 10篇 |
2008年 | 6篇 |
2007年 | 6篇 |
2006年 | 2篇 |
2005年 | 4篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 2篇 |
1998年 | 1篇 |
1995年 | 2篇 |
排序方式: 共有149条查询结果,搜索用时 15 毫秒
61.
62.
IEEE 1588标准的基本功能是使分布式网络内的各个时钟与最精确的时钟保持同步,目前主要用于以太网中,无线分组网中尚未移植该协议.本文旨在研究无线分组通信网精确定时技术,分析IEEE 1588定义的PTP(Precision Time Protocol)体系结构和时钟同步原理,提出能在无线分组网络中通过IEEE 15... 相似文献
63.
64.
介绍了波分和微波设备传输频率同步和1588的原理和架构后,给出了网络部署实现方法,探讨了网络时间的链路保护场景,最后对理论分析和实际测试结果进行了探讨。 相似文献
65.
电网一体化时间同步网的建设方案,主要是基于现有数字同步网和变电站时间同步系统,采用IEEE1588v2精确时间同步协议(PTP)传输时间同步信息,并在卫星同步源方面增加北斗同步系统,实现时间同步源的GPS、北斗和地面同步网天地互备格局,大大地提高电网时间同步可靠性的同时,实现全网同步。 相似文献
66.
Dr. Ashish D. Patel Dr. Thopallada Y. Pasha Paras Lunagariya Dr. Umang Shah Tushar Bhambharoliya Dr. Rati K. P. Tripathi 《ChemMedChem》2020,15(13):1229-1242
Protein tyrosine phosphatase 1B (PTP1B) is an important target for the treatment of diabetes. A series of thiazolidin-4-one derivatives 8 – 22 was designed, synthesized and investigated as PTP1B inhibitors. The new molecules inhibited PTP1B with IC50 values in the micromolar range. 5-(Furan-2-ylmethylene)-2-(4-nitrophenylimino)thiazolidin-4-one ( 17 ) exhibited potency with a competitive type of enzyme inhibition. structure–activity relationship studies revealed various structural facets important for the potency of these analogues. The findings revealed a requirement for a nitro group-including hydrophobic heteroaryl ring for PTP1B inhibition. Molecular docking studies afforded good correlation with experimental results. H-bonding and π–π interactions were responsible for optimal binding and effective stabilization of virtual protein-ligand complexes. Furthermore, in-silico pharmacokinetic properties of test compounds predicted their drug-like characteristics for potential oral use as antidiabetic agents.Additionally, a binding site model demonstrating crucial pharmacophoric characteristics influencing potency and binding affinity of inhibitors has been proposed, which can be employed in the design of future potential PTP1B inhibitors. 相似文献
67.
68.
69.
In this paper, a new class of optical multistage interconnection network (MIN) architecture is presented, which is constructed
utilizing a modularization approach rather than the traditional recursive or fixed exchange pattern methods. The modified
architecture consists of an input module, an output module, two point-to-point (PTP) modules, and one modified multicast/broadcast
(M/B) module(s). We also implement the multicast/broadcast module with WDM technique, which reduces the hardware cost required
for multicast and the re-computation cost for a new connection. We show that it has the best application flexibility and provides
multicast function without imposing significant negative impacts on the whole network. A new multicast connection pattern
is also proposed in this paper, which makes it practical and economical to apply amplification in space-division networks.
Compared with existing multicast architectures, this new architecture with Dilated Benes PTP modules has better performance
in terms of system SNR, the number of switch elements, and system attenuation in point-to-point connections. Moreover, the
multicast/broadcast module adopts wavelength division multiplexing (WDM) technique to increase its multicast/broadcast assignment.
As a result, given m available distinguished wavelengths, one M/B module can support at most m M/B requests at the same time. The new proposed M/B module with WDM is more practical and economical to apply amplification
in space-division networks. 相似文献
70.
Vignesh Sivaganesh Varsha Sivaganesh Christina Scanlon Alexander Iskander Salma Maher Th Lê Bela Peethambaran 《International journal of molecular sciences》2021,22(23)
Protein tyrosine kinases, especially receptor tyrosine kinases, have dominated the cancer therapeutics sphere as proteins that can be inhibited to selectively target cancer. However, protein tyrosine phosphatases (PTPs) are also an emerging target. Though historically known as negative regulators of the oncogenic tyrosine kinases, PTPs are now known to be both tumor-suppressive and oncogenic. This review will highlight key protein tyrosine phosphatases that have been thoroughly investigated in various cancers. Furthermore, the different mechanisms underlying pro-cancerous and anti-cancerous PTPs will also be explored. 相似文献