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991.
Whereas most research on Internetware has focused on new technologies for keeping track of a changing Internet,little attention has been paid to the software development process.A large portion of the software running the Internet is open source software.Open source software is developed both by volunteers and commercial companies,often jointly.Companies get involved in open source projects for commercial reasons,and bring with them a commercial software development process.Thus,it is important to understand how commercial involvement affects the software development process of open source projects.This article presents case studies of three open source application servers that are being developed jointly by a volunteer community and one primary software company.We are interested in better understanding developer behavior,specifically task distribution and performance,based on whether the developer is an external contributor,e.g.,a volunteer working in their spare time,or a commercial developer from inside the primary backing company who is being paid for their time.To achieve this,we look at issue reporting as an example of commercial involvement in open source projects.In particular,we investigate the distribution of tasks among volunteers and commercial developers by studying the source of reported issues and quantify the task performance on user experience via the issue resolution speed.We construct measures based on historical records in issue tracking repositories.Our results show that,with intensified commercial involvement,the majority of issue reporting tasks would be undertaken by commercial developers,and issue resolution time would be reduced,implying a better user experience.We hope our methods and results provide practical insights for designing an efficient hybrid development process in the Internetware environment. 相似文献
992.
Xun-Ru Yin Wen-Ping Ma Wei-Yan Liu Dong-Su Shen 《Quantum Information Processing》2013,12(9):3093-3102
An efficient bidirectional quantum secure communication protocol is proposed with two-photon entanglement. Compared with the previous protocol proposed by Shi et al., our protocol can achieve higher efficiency. Meanwhile, for the same length secret messages, only half of entangled photon pairs need to be prepared in our protocol. And the number of classical bits in public classical communication is also a half of that in the previous protocol. Moreover, the information leakage does not exist in our scheme. 相似文献
993.
Wei Wang Shuping Ma Chenghui Zhang 《International Journal of Control, Automation and Systems》2013,11(6):1138-1148
In this paper, the stability and static output feedback stabilization problems for a class of nonlinear discrete-time singular switched systems are discussed. First, based on Lyapunov theory and the implicit function theorem, linear matrix inequalities sufficient conditions are developed which guarantee that the nonlinear discrete-time singular switched systems are regular, causal, have unique solution in a neighborhood of the origin, and are uniformly asymptotically stable. Then, with these conditions, and based on singular value decomposition approach, the design method of static output feedback controllers is given. Last, numerical examples are provided to illustrate the effectiveness of the proposed methods. 相似文献
994.
This paper presents an entanglement purification protocol of multipartite electronic spin entangled state resorting to quantum-dot (QD) spin and micro cavity coupled system. The QD and microcavity coupling system is used to construct parity check detectors which provides a novel experimental platform of quantum information processing with photon and solid qubit. In this proposed protocol, the mixed multi-electron entangled state ensemble can be purified efficiently. 相似文献
995.
Pervasive computing applications often need to maintain uninterrupted computing experiences when users move across devices. This advanced feature, recognized as application mobility, brings many challenges to the pervasive computing community. For a better understanding of the challenges and existing approaches to application mobility, this paper surveys related work with a classification and comparison framework established along four dimensions of design concerns in application migration: temporal, spatial, entity and other concerns. Through this survey this paper attempts to provide a systematic reference for developers to leverage off among different migration strategies for seamless application mobility. Moreover, it sheds some light on future work directions. 相似文献
996.
Xiao San Ma Guang Xing Zhao Jia Yan Zhang An Min Wang 《Quantum Information Processing》2013,12(1):321-329
The effect of Dzialoshinski–Moriya (DM) interaction on the tripartite thermal entanglement of a spin-star model with four spins has been analyzed by an entanglement measure of the tripartite negativity. Our results imply that the tripartite thermal entanglement can be established among the three surrounding parties which do not interact with each other but interact with the central party independently. From the results, we find that the strong DM interaction can enhance the tripartite thermal entanglement while the high temperature can shrink it. The effect of the inhomogeneous coupling on the tripartite thermal entanglement is also discussed. 相似文献
997.
针对目前公路施工领域力学试验过程中数据可靠性低、不便于监测的缺点,设计了压力试验机网络监测系统;在论述了系统的总体结构的基础上,完成了试验数据采集与网络传输系统的软硬件设计、样品条形码信息管理系统设计,以及试验数据与信息查询系统设计;基于文章方法设计的网络监测系统已经在云南某高速公路工地试验室得到应用,实际运行情况表明,系统工作高效稳定,实现了对工地试验室试验过程的远程监督和管理,以及对样品的过程跟踪,可以有效保证工程项目的施工质量。 相似文献
998.
999.
1000.
以小型水利工程项目划分为对象,从质量监督确认工作角度出发,根据小型水利工程的特点,探讨在现有规程下针对实际不同工程的恰当的项目划分方式,以利参建各方更好地控制工程质量。 相似文献