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161.
介绍了公路路面工程质量控制要点 ,从路面的平整度、建立健全质量保证体系等方面进行了论述 ,指出强化工程监理、加大监督力度和提高人员素质是确保工程质量的有效途径 相似文献
162.
163.
后浇带质量控制的措施 总被引:1,自引:0,他引:1
后浇带起着超长建筑的温度伸缩、高层建筑高层部分与裙房间沉降缝的作用,已普遍采用,但有些工程由于施工不当,设了后浇带起不到应有作用,本文就施工中如何采取有效措施,对后浇带的质量进行控制,作了探讨,以期能真正发挥后浇带的作用。 相似文献
164.
The IEEE 802.11e medium access control (MAC) layer protocol is an emerging standard to support quality of service (QoS) in
802.11 wireless networks. Some recent work shows that the 802.11e hybrid coordination function (HCF) can improve significantly
the QoS support in 802.11 networks. A simple HCF referenced scheduler has been proposed in the 802.11e which takes into account
the QoS requirements of flows and allocates time to stations on the basis of the mean sending rate. As we show in this paper,
this HCF referenced scheduling algorithm is only efficient and works well for flows with strict constant bit rate (CBR) characteristics.
However, a lot of real-time applications, such as videoconferencing, have some variations in their packet sizes, sending rates
or even have variable bit rate (VBR) characteristics. In this paper we propose FHCF, a simple and efficient scheduling algorithm
for 802.11e that aims to be fair for both CBR and VBR flows. FHCF uses queue length estimations to tune its time allocation
to mobile stations. We present analytical model evaluations and a set of simulations results, and provide performance comparisons
with the 802.11e HCF referenced scheduler. Our performance study indicates that FHCF provides good fairness while supporting
bandwidth and delay requirements for a large range of network loads.
Pierre Ansel received a multidisciplinary in-depth scientific training in different fields such as Pure and Applied Mathematics, Physics,
Mechanics, Computer Science and Economics from the Ecole Polytechnique, Palaiseau, France. Then, he joined the Ecole Nationale
Superieure des Telecommunications, Paris, France in 2005 where he went further into electronics, databases, computer network
security and high speed networks. He received a multidisciplinary master of sciences degree and an additional master of sciences
degree in telecommunications in 2005. He did a summer internship in 2003 in INRIA, Sophia Antipolis, France where he worked
on the Quality of Service in 802.11 networks at Planete Group, France. Then in 2004, he joined France Telecom R&D, Issy-les-Moulineaux,
France to work on Intranet Security issues. He designed a WiFi security supervision architecture based on WiFi Intrusion Detection
Sensors. He is currently a French civil servant and belongs to the French Telecommunications Corps.
Qiang Ni received the B.Eng., M.Sc. and Ph.D. degrees from Hua Zhong University of Science and Technology (HUST), Wuhan City, China
in 1993, 1996 and 1999 respectively. He is currently a faculty member in the Electronic and Computer Engineering Division,School
of Engineering and Design, Brunel University, West London, U.K. Between 2004 and 2005 he was a Senior Researcher at the Hamilton
Institute, National University of Ireland, Maynooth. From 1999 to 2001, he was a post-doctoral research fellow in the multimedia
and wireless communication laboratory, HUST, China. He visited and conducted research at the wireless and networking group
of Microsoft Research Asia Lab during the year of 2000. From Sept. 2001 until may 2004, he was a research staff member at
the Planète group of INRIA Sophia Antipolis France. Since 2002, he has been active as a voting member at the IEEE 802.11 wireless
LAN standard working group. His current research interests include communication protocol design and performance analysis
for wireless networks, cross-layer optimizations, vertical handover and mobility management in mobile wireless networks, and
adaptive multimedia transmission over hybrid wired/wireless networks. He has authored /co-authored over 40 international journal/conference
papers, book chapters, and standard drafts in this field. He is a member of IEEE. E-mail: Qiang.Ni@ieee.org
Thierry Turletti received the M.S. (1990) and the Ph.D. (1995) degrees in computer science both from the University of Nice – Sophia Antipolis,
France. He has done his PhD studies in the RODEO group at INRIA Sophia Antipolis. During the year 1995–96, he was a postdoctoral
fellow in the Telemedia, Networks and Systems group at LCS, MIT. He is currently a research scientist at the Planete group
at INRIA Sophia Antipolis. His research interests include multimedia applications, congestion control and wireless networking.
Dr. Turletti currently serves on the Editorial Board of Wireless Communications and Mobile Computing. 相似文献
165.
商品住宅的质量关系着国家的未来和房地产业的兴旺,本文试图对住宅产品的质量现状、问题及成因进行分析,在此基础上提出进一步提高品住宅整体质量的看法: 相似文献
166.
文章从如何提高对工程量清单编制工作重要性的认识入手,分析了实现计价理念、计价侧重点和造价控制观念转变的必要性,重点阐述了提高工程量清单编制质量应给予足够重视的几个关键环节。 相似文献
167.
阐述了以“三个代表”要求建设高素质施工管理人员队伍的必要性 ,指出只要尊重知识、尊重人才 ,建立和完善激励机制 ,就能激发广大管理人员的积极性、主动性和创造性 相似文献
168.
隧道工程施工中应注意的问题 总被引:3,自引:2,他引:1
通过对海南省东线高速公路大茅山隧道施工的全程监理,阐明了在施工中应重点注意的几个问题,在此基础上,总结出隧道工程质量监督中必须做到的几点,以确保隧道工程施工安全及工程质量. 相似文献
169.
赵惠琴 《有色冶金设计与研究》2004,25(4):4-8
根据所使用的低水泥浇注料的性能,对中铝山西分公司检修厂4号焙烧炉制定了合理的烘烤曲线,提高了耐火内衬的质量,延长了内衬的使用寿命。 相似文献
170.
论工艺参数对烧结产质量的影响及分析 总被引:7,自引:0,他引:7
本文论述了正确认识烧结工艺参数对搞好烧结生产的意义,介绍了烧结工艺参数其及相互关系,详述了烧结主要工艺参数对其产质量的影响,提出了烧结工艺参数认识的几点结论性意见。 相似文献