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131.
针对预拷贝算法在起始、迭代、结尾3个阶段所表现出的不同特点,提出了基于运行阶段特征的虚拟机实时迁移技术(LMCOS, live migration based on the characteristics of the operation stages)。起始阶段引入比对初始内存页的变量传输技术以避免未改变内存部分的传输;迭代阶段引入计数排序传输方法以减少内存页的重传;结尾阶段引入调减虚拟机CPU时间片的策略以缩短停机时间。与预拷贝算法相比,LMCOS使停机时间平均减少53%,总迁移时间平均减少65%。 相似文献
132.
Among the most well‐established live media distribution technologies is content delivery network (CDN), which improves user‐perceived quality of service by delivering content from proxy servers deployed at the Internet's edge. In recent years, CDN providers started to tap into their subscribers' peer‐to‐peer (P2P) capacity to alleviate their server costs. Under the inherent peer dynamics, a major challenge of these hybrid CDN‐P2P systems is to provide efficient failure recovery with good quality of service guarantees at a reduced server cost. In this work we propose a cost‐effective failover solution named CDNPatch to address the aforementioned problem. CDNPatch enables peers to periodically precompute a few backup content suppliers by efficient information exchange and maintenance algorithms, and leverages auxiliary CDN servers and an economic server provisioning algorithm to reduce the chance of playback interruption occurring to peers. Our simulation results show that CDNPatch can mask the impact of peer dynamics of 3 real P2P systems, namely, SOPCast, PPStream, and PPTV, with 100 % failure recovery success rate and a failure recovery time less than 1 second at a cost of small P2P communication overhead of less than 1 kilobits per second, while using only 10%, 21%, and 51%, respectively, of the pure CDN scheme's server consumption. 相似文献
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134.
2018年非洲猪瘟疫情出现以来,全国及黑龙江省生猪生产、猪肉市场受到了较大的影响,生猪、能繁母猪存栏减少,生猪出场价格也经历了明显波动。2019年春节以后,随着省外调出量增加和猪源减少,黑龙江省生猪出场价格进入上升通道,超过了全国平均水平,白条猪肉批发价格和猪肉市场零售价格随之上行。通过对2019年黑龙江省生猪生产环节、屠宰加工环节、猪肉市场零售环节进行调研,对生猪出场价格、白条猪肉批发价格、猪肉零售价格、生猪和能繁母猪产能等指标进行分析,阐述了以生猪和猪肉市场为重点的肉类产销形势,为促进肉类产业高质量发展、提高市场保供能力提供参考。 相似文献
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1 000 kV特高压交流紧凑型线路三相导线布置紧凑且相间无接地构件,使得带电作业电场环境更为严峻,为确保线路建成后带电检修工作的安全开展,采用有限元法仿真计算了特高压交流紧凑型线路典型工况下不同作业位置的带电作业人员体表电场,分析了作业人员的体表场强分布特点和变化规律,提出了相应的安全防护措施。计算结果表明,在带电作业过程中作业人员头部和手尖等曲率半径较小的部位场强较大,在等电位工况下其体表场强最大,作业人员穿戴屏蔽效率为60 dB的特高压带电作业屏蔽服可满足安全要求。研究成果可为中国1 000 kV特高压交流紧凑型线路带电作业的安全开展提供技术依据。 相似文献
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138.
Anayat Bhat Shuang Li Daniel Hammler Martin J. Winterhalder Andreas Marx Andreas Zumbusch 《International journal of molecular sciences》2021,22(16)
The hydrolysis of nucleotides is of paramount importance as an energy source for cellular processes. In addition, the transfer of phosphates from nucleotides onto proteins is important as a post-translational protein modification. Monitoring the enzymatic turnover of nucleotides therefore offers great potential as a tool to follow enzymatic activity. While a number of fluorescence sensors are known, so far, there are no methods available for the real-time monitoring of ATP hydrolysis inside live cells. We present the synthesis and application of a novel fluorogenic adenosine 5′-tetraphosphate (Ap4) analog suited for this task. Upon enzymatic hydrolysis, the molecule displays an increase in fluorescence intensity, which provides a readout of its turnover. We demonstrate how this can be used for monitoring cellular processes involving Ap4 hydrolysis. To this end, we visualized the enzymatic activity in live cells using confocal fluorescence microscopy of the Ap4 analog. Our results demonstrate that the Ap4 analog is hydrolyzed in lysosomes. We show that this approach is suited to visualize the lysosome distribution profiles within the live cell and discuss how it can be employed to gather information regarding autophagic flux. 相似文献
139.
Mathieu Lehanneur 《Architectural Design》2009,79(3):42-47
In the following works, Mathieu Lehanneur readdresses our understanding of domestic spaces through the environmental systems that control and condition them. Such spaces are generally conditioned by centralised heating, cooling and ventilation systems that lump together many sensory qualities, including primary thermal controls as well as by-products of scent and sound, into a singular, mechanical system that fails to engage any of them fully. Lehanneur's projects look to separate these senses into systems distributed throughout the home, engaging each one specifically and locally, in an attempt to redefine the domestic spaces they are located within. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
140.
带电作业安全距离红外线警报器的研制与应用 总被引:1,自引:0,他引:1
针对输电线路带电工作时的安全距离只依靠人工监护掌控,容易造成安全作业出现问题,研制并应用安全距离红外线警报装置,从而避免由于操作人员和监护人员的疏忽和失误可能造成的安全事故。 相似文献