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101.
An appropriate assessment of end-to-end network performance presumes highly efficient time tracking and measurement with precise time control of the stopping and resuming of program operation. In this paper, a novel approach to solving the problems of highly efficient and precise time measurements on PC-platforms and on ARM-architectures is proposed. A new unified High Performance Timer and a corresponding software library offer a unified interface to the known time counters and automatically identify the fastest and most reliable time source, available in the user space of a computing system. The research is focused on developing an approach of unified time acquisition from the PC hardware and accordingly substituting the common way of getting the time value through Linux system calls. The presented approach provides a much faster means of obtaining the time values with a nanosecond precision than by using conventional means. Moreover, it is capable of handling the sequential time value, precise sleep functions and process resuming. This ability means the reduction of wasting computer resources during the execution of a sleeping process from 100% (busy-wait) to 1-1.5%, whereas the benefits of very accurate process resuming times on long waits are maintained. 相似文献
102.
Various molecular docking software packages are available for modeling interactions between small molecules and proteins.However,there have been few reports of modeling the interactions between metal ions and metalloproteins.In this study,the AutoDock package was employed to example docking into a di-iron binding protein,bacterioferritin.Each binding site of this protein was tested for docking with iron ions.Blind docking experiments showed that all docking conformations converged into two clusters,one for internal iron binding in sites within the metalloprotein and the other for external iron binding on the protein surface.Local docking experiments showed that there were significant differences between two internal iron binding sites.Docking at one site gave a reasonable root-mean-square deviation(RMSD) distribution with relatively low binding energy.Analysis of the binding mode quality for this site revealed that more than half of the docking conformations were categorized as having good binding geometry,while no good conformations were found for the other site.Further investigations indicated that coordinating water molecules contributed to the stability of binding geometries.This study provides an empirical approach towards the study of molecular docking in metalloproteins. 相似文献
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104.
本文简述了安钢信息化建设概况,介绍了安钢信息化建设中开发SAP预留系统的设计流程,阐述了预留系统实现的功能. 相似文献
105.
浅谈计算机网络安全与防御技术 总被引:1,自引:0,他引:1
石玮 《计算机光盘软件与应用》2010,(13)
本文通过分析计算机网络安全的概念与现状,针对网络安全防御的关键技术及策略进行分析,以其通过本文的阐述为计算机网络安全体系建设提供技术支持. 相似文献
106.
107.
High fidelity repeater false-target badly affects a radar system’s detecting, tracking, and data processing. It is an available approach of confronting false-target for radar that discriminates firstly and then eliminates. Whereas for the technique progress about the repeater false-target jam, it is more and more difficult to discriminate this jam in the time-domain, frequency-domain, or space-domain. The technique using polarization information to discriminate the target and false-target is discussed in th... 相似文献
108.
通过对Word2000文档文件删除后的磁盘结构及文档文件结构的分析研究.给出恢夏Word2000文档文件的技术过程。 相似文献
109.
110.
Xiang Li Ling Feng Lizhu Zhou Yuanchun Shi 《Knowledge and Data Engineering, IEEE Transactions on》2009,21(6):910-924
The rapid evolution of information and communication technology opens a wide spectrum of opportunities to change our surroundings into an Ambient Intelligent (AmI) world. AmI is a vision of future information society, where people are surrounded by a digital environment that is sensitive to their needs, personalized to their requirements, anticipatory of their behavior, and responsive to their presence. It emphasizes on greater user friendliness, user empowerment, and more effective service support, with an aim to bring information and communication technology to everyone, every home, every business, and every school, thus improving the quality of human life. AmI unprecedentedly enhances learning experiences by endowing the users with the opportunities of learning in context, a breakthrough from the traditional education settings. In this survey paper, we examine some major characteristics of an AmI learning environment. To deliver a feasible and effective solution to ambient learning, we overview a few latest developed enabling technologies in context awareness and interactive learning. Associated practices are meanwhile reported. We also describe our experience in designing and implementing a smart class prototype, which allows teachers to simultaneously instruct both local and remote students in a context-aware and natural way. 相似文献