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81.
Since optical network carries a lot of traffic, survivability is very important to ensure the service continuity against network failures. Recently, multicast services become more popular to meet the huge multimedia demand in network, so that multicast survivability in optical network has got more attention. However, multicast survivability may lead to more energy consumption due to more redundant backup resources allocated. Since greening network is particularly important with the energy crisis keeping growing, green multicast survivability in optical network is a challenging issue. This paper focuses on the green multicast grooming protection problem in optical network and designs two auxiliary graphs that includes a virtual topology graph and an integrated graph to address the survivable multicast grooming, routing and wavelength assignment. Based on the auxiliary graphs, this paper proposes an efficient heuristic called green multicast grooming algorithm based on spanning path dedicated protection (GMG-SPDP), in which the network reliability and the energy efficiency are jointly taken into account. Simulation results show that, compared to other algorithms, the proposed GMG-SPDP not only has lower blocking probability and higher bandwidth utilization ratio, but also saves more energy. 相似文献
82.
83.
This paper provides an overview of p-cycle based optical multicast protection approaches for link failure recovery, combined node and link failure recovery, and source failure recovery on top of combined node and link failure recovery. We discuss several recently proposed p-cycle based optical multicast protection approaches, including the link-protecting p-cycle based optical multicast protection approach, the tree-protecting p-cycle based optical multicast protection approach, node-and-link protecting p-cycle based optical multicast protection approach, and flow p-cycle based optical multicast protection approach. They outperform other existing optical multicast protection approaches in both capacity efficiency and recovery speed. 相似文献
84.
Norihiro Tokitoh Takahiro Sasamori Nobuhiro Takeda Shigeru Nagase 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1473-1476
The first stable phosphabismuthene (R 1 --P=Bi--R 2 ) and stibabismuthene (R 1 --Sb=Bi--R 2 ) were successfully synthesized by taking advantage of efficient steric protection groups, 2,4,6-tris[bis(trimethylsilyl)methyl]phenyl (Tbt), 2,6-bis[bis(trimethylsilyl)-methyl]-4-[tris(trimethylsilyl)methyl]phenyl (Bbt), and 2,4,6-tri- t -butylphenyl (Mes*). Their spectroscopic properties and structural parameters were systematically compared with those of previously reported stable, homonuclear, doubly bonded systems, such as diphosphene, diarsene, distibene, and dibismuthene. 相似文献
85.
A reproducible synthesis of 2,5-anhydro-1-amino-1,4-dideoxy-3-thio-D-threo-pentitol hydrochloride (2b) via the Staudinger reaction with triethyl phosphite was developed. An unexpected ethyl migration from an oxygen to the nitrogen of iminophosphorane 7 was observed. 相似文献
86.
孟利青 《电信工程技术与标准化》2014,(11)
针对电信运营商短信营业厅系统易受垃圾短信影响的问题,给出一种基于贝叶斯算法的短信营业厅防护系统构建方法,即在现有系统的基础上,另外构建一个与现有业务系统无耦合的独立系统,部署在短信营业厅系统前端进行短信预处理。新系统主要由文本特征提取模块、分类模块、过滤模块组成,对接收到短信按贝叶斯算法进行分类,按规则库进行过滤和清洗垃圾短信,将有价值的短信送到短信营业厅系统处理,减少垃圾短信对系统资源的开销。理论分析显示,利用所建系统,可达到对短信营业厅有效防护效果。实践证明,防护系统应用后,短信营业厅系统资源消耗下降。 相似文献
87.
本文在分析电动机过载保护的基本规律的基础上,提出软起动器智能控制器对电动机过载实现反时限保护特性的一套利用数值积分法实时测量和控制的数学模型和控制方法。应用这种方法即可提供对电动机过载曲线较吻合的保护特性,又可较好的解决负载不断变化情况下的热记忆问题。 相似文献
88.
Eerik Halonen Vesa PynttäriJuha Lilja Hannu SillanpääMatti Mäntysalo Jouko HeikkinenRiku Mäkinen Tero KaijaPekka Salonen 《Microelectronic Engineering》2011,88(9):2970-2976
Electrically conductive silver nanoparticle ink patterns were fabricated using the inkjet printing method. Two different polymer films were used as the substrate materials. The patterns were exposed to humidity and salt fog and the electrical performance (sheet resistance and RF performance) as well as mechanical endurance (adhesion) were measured before and after the environmental tests. The electrical properties of the printed structures remained good in all the measurable samples. The adhesion between the ink and a substrate material appeared to be a greater challenge in harsh environments. Protection capabilities of one dip coated and one hot laminated barrier materials were evaluated during the environmental tests. The results showed that there is a need for environmental protection in printed electronics. Especially the laminated barrier films can offer a potential solution for shielding printed electronics in harsh environments as they can provide good mechanical protection, and can easily be integrated in roll-to-roll process. 相似文献
89.
《个人信息保护法(草案)》吸收了近年来个人信息保护的国际经验以及国内《网络安全法》《民法典》等立法、标准和实践经验,既与国际接轨,又不乏中国特色.现有草案存在部分场景坚持"同意为王"的治理模式、缺乏对个人信息处理者"合法利益"的保障、未区分"去标识化"个人信息与一般个人信息处理规则等问题.在体系定位方面,正在制定中的个... 相似文献
90.