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91.
本文从C/C复合材料的基体入手,研究了基体沥青、焦炭中添加氧化物的工艺条件及其在复合材料中的作用.结果表明,添加氧化物对基体改性,不仅能提高C/C复合材料的高温抗氧化性,也能对其它性能带来很大影响.只要控制适当的工艺条件,就可以得到高性能的C/C复合材料. 相似文献
92.
胡才雄 《有色金属材料与工程》1992,(1)
结合器件工艺的失效分析,评述了硅中缺陷和氧、碳、金属杂质与器件性能、器件工艺之间的相互关系。指出:杂质和缺陷对器件的性能、成品率和可靠性有严重的影响,尤其经金属杂质缀饰的缺陷对器件的危害更大。对硅中某些杂质和缺陷的最新研究进展作了介绍。 相似文献
93.
Verbruggen Frederick; Liefooghe Baptist; Vandierendonck André; Demanet Jelle 《Canadian Metallurgical Quarterly》2007,33(2):342
In the task-switching literature, it has frequently been demonstrated that although advance task preparation reduces the switch cost, it never really eliminates the switch cost. This remaining residual switch cost received much attention, and it has been argued that advance preparation is restricted in nature. In the present study, the role of task-cue presentation in the establishment of the residual switch cost was investigated. In 4 experiments, the cue was removed during the preparation interval, and it was hypothesized that this would encourage participants to complete advance task preparation. The results of all 4 experiments provided support for this hypothesis: When the cue was presented for a short time and then removed, the residual switch cost completely disappeared. This was found for different cue types. Furthermore, Experiment 3 demonstrated that it was not the presence of the cue itself but merely differences in advance task preparation that caused the effects. This suggests that advance task preparation is not as restricted in nature as previously assumed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
中国第一口超千米深水钻井液技术 总被引:3,自引:1,他引:2
LW3-1-1探井位于中国南海珠江口盆地,作业水深1480m,完钻井深为3843m,地层以大套灰色泥岩和页岩为主,具有强水敏性.要求钻井液具有良好的流变性、润滑性、抑制性,良好的抗盐、抗钙、抗高温和抗低温能力,以及强的天然气水合物抑制能力。该井采用了PFMX钻井液体系,钻井周期为49d,介绍了钻井液工艺及现场应用情况。PFMX体系表现出很多油基钻井液的优点,如好的润滑性、高的钻进速率、膜效应、强的井眼稳定及页岩抑制性,解决了强水敏性地层的井壁稳定等问题,还解决了深水钻井中遇到的挑战,如低的破裂压力梯度、天然气永合物、浅层水流、深水低温等问题,满足了该区块作业需要。 相似文献
95.
容错磁盘阵列的性能模型 总被引:1,自引:1,他引:0
本文以排队论为工具,建立了容错磁盘阵列的M/G/1排队模型,并在此基础上分析了RAID的平均响应时间,稳定数据传输率等重要性能指标;比较了同步和异步RAID的性能差异,最后提出了以吞吐率作为衡量RAID性能的综合指标,并给出了确定最大吞吐率的定量。 相似文献
97.
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99.
Carl Staelin 《Software》2005,35(11):1079-1105
lmbench is a powerful and extensible suite of micro‐benchmarks that measures a variety of important aspects of system performance. It has a powerful timing harness that manages most of the ‘housekeeping’ chores associated with benchmarking, making it easy to create new benchmarks that analyze systems or components of specific interest to the user. In many ways lmbench is a Swiss army knife for performance analysis. It includes an extensive suite of micro‐benchmarks that give powerful insights into system performance. For those aspects of system or application performance not covered by the suite, it is generally a simple task to create new benchmarks using the timing harness. lmbench is written in ANSI‐C and uses POSIX interfaces, so it is portable across a wide variety of systems and architectures. It also includes powerful new tools that measure performance under scalable loads to analyze SMP and clustered system performance. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
100.
Service life planning comprises a model for the determination of a reasonable expected service life for buildings and components, and it establishes a routine for the assessment of design alternatives. A design option is considered reasonable when it meets or exceeds performance requirements over time that have been drawn up specifically for the specific project. Due to this assessment reference, there is a very evident link to the concept of performance-based building. Any stakeholder involved in the value chain or in the design process of the building, as well as regulators and building users, can express performance requirements. Identified requirements, both in relevance and in quality, will vary with the stakeholder and his/her perspective of interest. As building sector manufacturers develop most products with reference to standards rather than with reference to specific requirements, there is no direct link from user requirements to the product design. Instead, the building designer has the responsibility to ensure performance requirements are met by the performance of products integrated into the design. As these design decisions also have to be made at the material and component level, a performance-based building would benefit from an established rationale that enables the communication of performance requirements across the relevant system levels in the relevant design processes. A path for the connection of the established concepts of service life planning and performance-based building is presented. The aim is to identify key elements that need to be developed for the successful linkage of performance-based building with service life planning. 相似文献