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91.
严惠勤 《铁合金》2002,33(3):20-22
针对电炉热量大,水温高,水冷设备容易结垢的运行特点,总结了应用全有机配方GSP-518和杀菌灭藻剂GSP-11进行循环冷却水水质稳定处理的经验。  相似文献   
92.
The current paper presents a collection of experimental data portraying the performance achieved in the wireless setting by several TCP-friendly congestion controls recently proposed in literature. This work is partly motivated by the consideration that the majority of the analytical results in this area are validated by simulation, rather than by field tests. Examining these algorithms in real environments can help verify their actual effectiveness over the wireless Internet. To reach such goal, two representative controls among the so-called window-based TCP-friendly schemes have been implemented, namely, the General Additive Increase Multiplicative Decrease (GAIMD) strategy, and the SQuare RooT (SQRT) binomial control; the most representative algorithm among rate-based controls, the TCP Friendly Rate Control (TFRC), has also been considered. Their TCP-fairness and smoothness have been comprehensively evaluated in an IEEE 802.11g Wireless Local Area Network (WLAN). The obtained results show that the GAIMD and SQRT strategies reveal non-negligible scalability and smoothness problems, that markedly limit their performance. It is empirically demonstrated that their “optimal” increase/decrease rules, based on TCP-Reno analytical model, cannot guarantee an adequate performance when GAIMD and SQRT compete with TCP-Sack, a de facto standard for current TCP implementations. TFRC is demonstrated to occasionally behave bewildering: properly tuning one of its congestion control parameters and enhancing the algorithm with a flow-control mechanism result in a definitely fairer share of bandwidth with concurrent TCP flows. Michele Borri received the M.Sc. degree in Computer Engineering from the University of Modena and Reggio Emilia in the academic year 2001–2002 and took a specialisation in Telecommunication Engineering in 2002. His professional activity is currently balanced between researching at the University of Modena and Reggio Emilia, and consulting as a system engineer and network architect. His research interests focus on congestion control and multimedia services in next generation Internet. Michele Borri has been participating to national research projects promoted by the Italian National Research Council (CNR). Maurizio Casoni is Associate Professor in Telecommunications at the University of Modena and Reggio Emilia. He graduated with honors in Electrical Engineering at the University of Bologna in 1991, with a grant by Telecom Italia and received the Ph.D. degree also in Electrical Engineering from the University of Bologna, in 1995. In 1995 he was with the Computer Science Department at Washington University in St. Louis, MO, as a research fellow where he worked on ATM broadband switching architectures. He has studied ATM broadband switching architectures and Clos architectures for the design of large photonic switches in the framework of the European Projects ATMOS and KEOPS. He has also investigated the performance of 3rd generation UMTS systems. His current research interests deal with Optical Networking, mainly focusing on Optical Burst Switching, and Satellite Networks. He currently holds the course of Interconnection Systems for undergraduate students and the course of Switching Systems for graduate students of Telecommunications Engineering. Maria Luisa Merani is currently an associate professor of Telecommunication Networks at the University of Modena and Reggio Emilia, Department of Information Engineering. She is an IEEE Senior member and has served on the Technical Program Committees of several major communication conferences (IEEE ICC, IEEE Globecom, IEEE VTC, APCC). In 2005 she has been technical program cochair of the second IEEE International Symposium in Wireless Communication Systems. In 2007 she will be the Wireless Symposium chair of IEEE Globecom. At present she is involved in research on congestion control for next generation Internet and on multicast video streaming. Her most recent research interests are related to the area of radio communications, with emphasis on performance evaluation of mobile radio systems, 3G data networking and transport solutions for optical networks. Maria Luisa Merani received both her M.Sc. (summa cum laude) and Ph.D. in electrical engineering from the University of Bologna, Italy, in the academic years 1985/86 and 1991/92, respectively. In 1992 she spent one year at the Computer Science Department of the University of California in Los Angeles, CA, USA.  相似文献   
93.
文中分析了吕梁西部五大流域水利工程现状及存在问题。论述了其滩地、水地开发目标及建设内容,并进行了可行性分析。  相似文献   
94.
通过对中国图书馆分类法和中国科学院图书馆图书分类法及测绘学叙词表等相关资料的分析,确定本体中的类和定义类的语义关系,基于Protégé工具构建测绘学科信息公共本体、测绘学科分类—中图法本体及测绘学科分类—科图法本体,在构建的本体基础上基于Oracle 11g语义技术构建测绘学科分类本体库,为进一步语义检索提供基础.  相似文献   
95.
A series of chitosan‐graft‐polyacrylamide copolymers have been prepared as flocculants for waste water treatment. The results indicated that the grafting ratio was one of the key factors for the flocculating effects. The copolymers with various grafting ratios showed different flocculating properties. To observe every detail of this effect, the specific refractive index increment measurement (SRIIM) method was used to determine the grafting ratio at the beginning of this study. Interestingly, it was found that as the grafting ratio increased, the flocculating effect increased until it reached its maximum point. At that point, it decreased. This result was discussed in terms of the cooperative effects of the charge neutralization and bridging flocculating mechanisms. A structure model of chitosan‐g‐polyacrylamide copolymer flocculants has been proposed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
96.
介绍了S模式询问机接口管理的工作原理、硬件电路和软件实现,阐述了系统的综合 管理功能,分析了接口管理实现过程中的关键技术。该接口管理模块在S模式询问机上已经 得到很好的验证和试验,具有性能稳定、扩展性强、功能强大等优点。  相似文献   
97.
通过AEO-9和TX-10,与顺酐及亚硫酸钠反应合成了烷基(酚)聚氧乙烯醚磺基琥珀酸单酯二钠盐,得到其较佳合成条件为:酯化反应n(醚):n(酐)=1:1.05,反应温度为90℃,反应时间为3h;磺化反应温度为85℃,反应时间为2h。测定了所得产物的表面活性并进行脱墨应用,结果表明,与生产用脱墨剂相比,其脱墨后白度提高,残余油墨量下降。  相似文献   
98.
负加速度试飞是民用飞机适航取证试验的重要组成部分,民机负加速度试飞在国内尚属首次,具有对机组操纵技术要求高、风险难度大的特点。本文结合已经完成的燃油系统负加速度试飞,对负加速度时飞机的飞行状态,动作要领进行了总结。另外,对负加速度飞行时动力装置的燃油系统的工作情况进行了分析。  相似文献   
99.
The paper presents experimental results of evaluation of the data transfer speed between a mobile object and base stations of a wireless 802.11.g standard network. Estimates are produced for different velocities of object motion. At the same time, measurement was carried out on the signal-to-noise ratio in a channel. A functional relation has been established between the real data transfer speed and the signal-to-noise ratio in the channel of the wireless net connected to a mobile object.  相似文献   
100.
对加固型CC4007NMOS器件进行了低温(-30℃)和室温(25℃)γ射线辐射实验、不同剂量率下的γ辐射实验以及不同温度下的退火实验。根据实验结果,利用归一化迁移率与界面态电荷的机理模型,分析了辐射环境温度、辐射剂量率以及退火温度对NMOS器件迁移率的影响。  相似文献   
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