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991.
广东省水利业务一体化管理系统是广东省水利数据中心工程(数据中心工程)的重要组成部分,项目具有集成度高、大型、复杂等特点。基于传统的手工测试方法在一体化系统测试工作中严重制约了测试乃至项目研发的效率,通过实践文中提出了一种基于Watir的自规范测试方法,在有效降低一体化系统测试成本、缩短项目开发周期、提高项目研发效率的基础上消除了自动化测试带来的bug重现率降低的问题。该方法具有高效、可靠、稳定、便于实现等优点。 相似文献
992.
随着视频监控“大联网”大趋势的展开,国家标准的正式施行表明视频监控“大联网”已经成为必然趋势。为解决基于SIP协议的集中监控管理系统中负载过重的问题,提出了一种新型的基于SIP协议的跨区域分层SIP监控系统集成平台。该平台包括分层设计、模型结构、远程控制和智能监控功能的设计等综合多功能集中监控平台。系统采用网络技术、传输技术、组包技术、交换技术、储存器技术、服务器技术和基于网络分层的开放的会话发起协议( SIP)架构,系统的各成员之间可以在域内处理大量的信令信息和媒体流信息,具有可扩展性、智能性、灵活性、自主性和互操作性等多种优点,可以解决跨区域监控系统集中管理中的负载过重问题并提供响应更灵活方便的控制及扩展功能。 相似文献
993.
994.
亚硫酸盐―甲醛―蒽醌(SFP-AQ)法是适合于草类原料的一种制浆方法。文章研究了氧脱木质素对稻草SFP浆的卡伯值、白度、粘度及强度性能的影响。结果表明,较高的用碱量有助于残余木质素的脱除,在合适的工艺条件下,稻草SFP浆单段氧脱木质素的脱木质素率可达50%以上。在氧脱木质素用碱量3.5%、氧压0.4 MPa、温度110℃、时间60 min或90 min的条件下,稻草SFP浆的卡伯值较低、白度较高,而同时具有良好的粘度和强度性能。 相似文献
995.
Flow influenced electrochemical corrosion of nickel aluminium bronze – Part I. Cathodic polarisation
G. Kear B. D. Barker K. Stokes F. C. Walsh 《Journal of Applied Electrochemistry》2004,34(12):1235-1240
The cathodic polarisation behaviour of CA 104 nickel aluminium bronze (NAB) has been examined in fully characterised seawaters (filtered and artificial) using the rotating disc electrode (RDE) and the rotating cylinder electrode (RCE). Linear sweep voltammetry and a potential step, current transient technique were used to examine the charge transfer and mass transfer controlled cathodic response as a function of both laminar and turbulent fluid flow. For freshly polished surfaces, the rate of irreversible charge transfer controlled oxygen reduction is controlled by the exchange of a single electron and hydrogen evolution is only significant at potentials more negative than approximately –1.0 V vs. the saturated calomel electrode (SCE). 相似文献
996.
997.
Cognitive radios such as intelligent phones and Bluetooth devices have been considered essential goods in next-generation communication systems.Such devices will have to share the same frequency band owing to the limited bandwidth resource.To improve spectrum efciency,we formulate multi-channel power allocation as a market competitive equilibrium(CE)problem,and prove that its solution exists and is unique under the condition of weak interference.We then propose two distributed power allocation algorithms achieving CE,namely the fast convergent power allocation algorithm(FCPAA)and the social-fairness-aware FCPAA(SFAF).Theoretical analysis and simulation results demonstrate that the proposed algorithms lead to better system performance in terms of the guaranteed interference temperature constraint using the price mechanism instead of a strategy based on the Nash equilibrium.Moreover,it is shown that the FCPAA maximizes total utility,and converges more quickly than the method addressed in prior research with the help of improved round-robin rules.However,the FCPAA cannot ensure the same social fairness among secondary users as the SFAF scheme in both the non-fading channel and Rayleigh fading channel;the SFAF balances the individual utility by adjusting each user’s budget at the expense of a small quantity of system total throughput. 相似文献
998.
In this paper, the decentralized transceivers and corresponding channel state information (CSI) signaling concepts are proposed for weighted sum rate (WSR) maximization, via linear downlink transceiver" optimization in multi-relay aided multiuser multiple-input multiple-output (MIMO) networks. Three decentral- ized algorithms are proposed with the local CSI requirements at the base station (BS) and the relay nodes. In the first proposed algorithm, the generalized channel inversion precoding is used at the BS to avoid the second hop channel sharing requirements among the relay nodes, and decentralized transceiver optimization of the relay nodes and users are developed to maximize the WSR. A minimum mean square error (MMSE)-based enhanced method is proposed as well. To further improve the performance, we provide a novel structure of the precoding matrix of the BS. The decentralized joint BS, relay and user transceiver optimization problem is formulated and solved. Also, the CSI signaling and decentralized processing in the time division duplex (TDD) system are analyzed. Simulation results show the effectiveness of the decentralized transceiver design compared to the existing algorithms. 相似文献
999.
1000.
In this article,a new simulated annealing based bit error rate pairing scheduling(SA-BPS)algorithm for LTE femtocell uplink virtual multiple input multiple output(V-MIMO)systems is proposed,which uses Round Robin(RR)criterion to decide the first user,and simulated annealing(SA)algorithm with objective function of bit error rate(BER)is suggested to decide the pairing users.The SA-BPS is considered not only to be used for inner layer user pairing within femtocell user equipments(HUEs)to increase spectrum efficiency,but also to be used for cross layer user pairing between HUEs and macrocell user equipments(MUEs)to cancel the cross layer interference from MUEs to HUEs.As a growth control coefficient is used in SA-BPS to control the growth of average BER of users in the pairing group,rapid user BER deterioration can be prevented by adopting a proper coefficient.Simulation results show that,the SA-BPS outperforms RPS,DPS,and the conventional SA algorithm in terms of BER performance,whether used for inner layer user pairing or cross layer user pairing.Also,the mode switching signal to interference ratio(SIR)threshold between inner and cross layer user pairing are obtained by simulation in three cross layer interference power distribution scenarios. 相似文献