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31.
由于爱立信厂家未能提供用户模型、设备配置和SGSN实际容量之间的内在关系解释以及系统CPU负荷、SGSN实际容量的计算方法,为此,本文主要通过对现网数据进行计算及研究,建立一套行之有效的容量分析、监控预警体系来解决这一问题。 相似文献
32.
耐盐性高吸水树脂的研究进展 总被引:5,自引:0,他引:5
综述了近年来国内外提高吸水树脂耐盐性的研究进展,概述了高吸水树脂的结构和吸水机理,归纳了引入亲水单体、降低树脂颗粒微环境的盐浓度等提高吸水树脂耐盐性的方法。 相似文献
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介绍了地层测试器密封设计中常用的材料、影响密封性能的主要因素;定性地论述了井下工具密封设计中应遵循的原则及注意事项。 相似文献
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W. L. Pearn M. H. Shu B. M. Hsu 《The International Journal of Advanced Manufacturing Technology》2004,24(1-2):140-147
The multiprocess performance analysis chart (MPPAC) based on the process capability index
Cpm, called Cpm MPPAC, is developed for analysing the manufacturing quality of a group of processes in a multiple process environment. The Cpm MPPAC conveys critical information of multiple processes regarding the departure of the process and process variability from one single chart. Existing research works on MPPAC are restricted to obtaining quality information from one single sample of each process ignoring sampling errors. The information provided from existing MPPAC charts, therefore, is unreliable and misleading and results in incorrect decisions. In this paper, we consider the natural estimator of Cpm based on multiple samples. Based on the natural estimator of Cpm, we consider the sampling errors by providing an explicit formula with the Matlab program to obtain the estimation accuracy of the Cpm. We tabulate the sampling accuracy of Cpm for sample size determination so that the engineers/practitioners can use it for their in-plant applications. An example of multiple precision voltage reference (PVR) processes is presented to illustrate the applicability of
Cpm MPPAC for manufacturing quality control. 相似文献
37.
The exploitation of the salient features of capability-based addressing environments leads to a high number of small objects existing in memory at the same time. It is thus necessary to enhance the efficiency of the mechanisms for object relocation, and to avoid congestion of input/output devices due to swapping. In this paper, we present an approach to the management of a large virtual memory space aimed at solving these problems. We insert partial information concerning the physical allocation of each object into the virtual identifier of this object. Objects are grouped into large swapping units, called pages. The page size is independent of the average object size. This results in enhanced efficiency in managing the relocation information both with regard to memory requirements and access times. The allocation of objects into pages, and the movement of pages through the memory hierarchy, are controlled by user processes. This means that programs which have knowledge of their own use of virtual memory can increase their locality of reference, diminish the number of swap operations and reduce fragmentation. 相似文献
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Marta Guerini Pietro Grisoli Cristina Pane Paola Perugini 《International journal of molecular sciences》2021,22(2)
The aim of this work was the development of microstructured lipid carriers (MLC) based on chitosan (CH) and containing N-acetylcysteine (NAC), a mucolytic and antioxidant agent, to inhibit the formation of Pseudomonas aeruginosa biofilm. MLC were prepared using the high shear homogenization technique. The MLC were characterized for morphology, particle size, Z potential, encapsulation efficiency and drug release. The antioxidant properties of NAC-loaded microstructured carriers were evaluated through an in vitro spectrophotometer assay. Finally, the activity of NAC-CH-MLC on biofilm production by Pseudomonas aeruginosa was also evaluated. Results obtained from this study highlighted that the use of chitosan into the inner aqueous phase permitted to obtain microstructured particles with a narrow size range and with good encapsulation efficiency. NAC-loaded MLC showed higher antioxidant activity than the free molecule, demonstrating how encapsulation increases the antioxidant effect of the molecule. Furthermore, the reduction of biofilm growth resulted extremely high with MLC being 64.74% ± 6.2% and 83.74% ± 9.95%, respectively, at 0.5 mg/mL and 2 mg/mL. In conclusion, this work represents a favorable technological strategy against diseases in which bacterial biofilm is relevant, such as cystic fibrosis. 相似文献