排序方式: 共有37条查询结果,搜索用时 0 毫秒
1.
介绍了使用随机进程代数作为性能建模的一种方法,着重介绍了Hillston提出的性能评价进程代数(PEPA),主要论述了使用PEPA模型性能评价方法及特点,讨论资源利用率系统性能分析方法,最后归纳了性能评价进程代数(PEPA)研究的应用领域,并对未来研究方向提出了展望. 相似文献
2.
硼酸锌对MPP/PEPA阻燃PP性能的影响 总被引:1,自引:0,他引:1
采用多聚磷酸蜜胺(MPP)和笼状季戊四醇磷酸酯(PEPA)复配阻燃剂,制备了具有良好阻燃性能的无卤阻燃PP。研究了MPP/PEPA质量比和硼酸锌(ZB)用量对PP阻燃和力学性能的影响。结果表明:MPP/PEPA质量比为3∶2时,复配效果最好;添加少量的ZB即可显著提高材料的阻燃性能;当MPP/PEPA/ZB添加量分别为12%、8%和2%时,阻燃PP的氧指数高达35%,并具有较好的力学性能。TGA结果表明:添加ZB可以起催化MPP/PEPA酯化,促进成炭的作用;SEM分析表明,ZB可以起到稳定炭层,增加炭层厚度的作用。 相似文献
3.
4.
4A分子筛对PP/MPP/PEPA膨胀阻燃体系的协同作用 总被引:4,自引:0,他引:4
冯才敏 《材料科学与工程学报》2009,(4)
以4A分子筛为阻燃协效剂,采用多聚磷酸蜜胺(MPP)和笼状季戊四醇磷酸酯(PEPA)复配阻燃剂,制备了具有良好阻燃性能的无卤阻燃PP。研究了4A分子筛用量对PP阻燃性能和协同作用的影响。结果表明:添加少量的4A分子筛即可显著提高PP的阻燃性能;当MPP/PEPA/4A分子筛添加量分别为12%、8%和2%时,阻燃PP的氧指数高达33。TGA、FTIR分析和体视显微镜及SEM观测结果表明:添加少量的4A分子筛可以催化MPP/PEPA间的酯化反应,促进体系成炭,形成更致密的炭层,从而提高材料的阻燃性能。 相似文献
5.
6.
Given the popularity of smart environment in a hospital involving the participation of a large group of patients, scheduling of patients towards their desired des-tination is still being a challenging issue. With the devel-opment of Internet of Things (IoT), smart environments are increasingly being deployed in various public scenar-ios and in particular, hospitals are an important target environment for smart environments. This paper models a dynamic scheduling policy based on a patient flow sce-nario in order to solve the queuing issue and facilitate peo-ple's experience. The dynamic scheduling policy aims to forward incoming patients to dissolve jams especially at the peaks by giving accurate predication of appointment time. The main modelling technique is a formal method— Performance evaluation process algebra (PEPA). The findings show that the dynamic scheduling policy is able to efficiently improve the patient flow. 相似文献
7.
TiO_2对PP/MPP/PEPA膨胀阻燃体系的协同作用 总被引:3,自引:0,他引:3
冯才敏 《材料科学与工程学报》2009,(2)
以TiO2为阻燃协效剂,采用多聚磷酸蜜胺(MPP)和笼状季戊四醇磷酸酯(PEPA)复配阻燃剂,制备了具有良好阻燃性能的无卤阻燃聚丙烯(PP)。研究了TiO2用量对PP阻燃性能和协效作用的影响。结果表明:添加少量的TiO2即可显著提高PP的阻燃性能;当MPP/PEPA/TiO2添加量分别为12%、8%和1%时,阻燃PP的氧指数高达31.5。TGA和FTIR分析及SEM和体式显微镜观测结果表明:添加TiO2可以催化MPP/PEPA间的酯化反应,促进体系成炭,形成更致密的炭层,从而提高材料的阻燃性能。 相似文献
8.
Tony Tsang 《通讯和计算机》2013,(5):686-692
GEPON (gigabit Ethemet passive optical network) is widely deployed to realize the economical FTTH (fiber-to-the home) system for supporting high speed Internet and video distribution service. Looking ahead, next home FTTH standardization activities, 10G-EPON, were completed at the IEEE 802.3av Task Force in 2009, and the standards had specified the co-existence of 10G-EPON on the same exist optical access distribution network as a cost-effective solution. A key device in such a system is an optical receiver IC (integrated circuit) with a quick response and high sensitivity that realizes high efficiency in data transmission. This paper also reports burst-mode optical receiver ICs fabricated using 0.25 ktm SiGe BiCMOS (Silicon-germanium Bipolar Complementary Metal Oxide Semiconductor) technologies for a 10G-EPON system, which is a promising access network for a next generation PON system. The results show that SiGe BiCMOS can provide high performance and cost effective receiver ICs for 10G-class PON systems. The authors use PEPA (performance evaluation process algebra) to evaluate a typical PON system's performance. The approach is more convenient, flexible and lower cost than the former simulation method which needs to develop special hardware and software tools. Moreover, they can easily analyze how changes in performance depend on changes in a particular mode by supplying ranges for parameter values. 相似文献
9.
PEPA阻燃环氧树脂的性能研究 总被引:2,自引:1,他引:1
将反应型含磷阻燃剂1-氧代-4-羟甲基-2,6,7-三氧杂-1-磷杂双环[2.2.2]辛烷(PEPA)与环氧树脂(EP)反应制得含磷EP,经固化剂间苯二胺固化后得到阻燃EP.表征了阻燃EP的热稳定性、成炭性和阻燃性能等.结果显示,PEPA的羟基与EP的环氧基团发生反应,使EP环氧当量提高.随着PEPA含量增加,阻燃EP的氧指数逐渐增大,起始分解温度降低,最终质量保持率增大.PEPA的加入对阻燃EP的玻璃化转变温度影响不大.燃烧后形成的炭层表面结构致密,内部多孔. 相似文献
10.
Cr2O3增效阻燃PP的制备及其热降解性能的研究 总被引:1,自引:0,他引:1
以Cr2O3为阻燃协效剂,采用多聚磷酸蜜胺(MPP)和笼状季戊四醇磷酸酯(PEPA)复配阻燃剂,制备了具有良好阻燃性能的无卤阻燃PP.研究了Cr2O3添加量对PP阻燃性能和协效作用的影响.结果表明:添加少量的Cr2O3可显著提高PP的阻燃性能.当MPP/PEPA/Cr2O3添加量分别为12%、8%和2%时,阻燃PP的氧指数高达31.5%.TGA、FTIR和Flynn-Wall法热降解活化能分析结果表明:添加Cr2O3可以起催化MPP/PEPA酯化,促进成炭的作用,使PP的活化能提高. 相似文献