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Inadequate energy of sensors is one of the most significant challenges in the development of a reliable wireless sensor network (WSN) that can withstand the demands of growing WSN applications. Implementing a sleep-wake scheduling scheme while assigning data collection and sensing chores to a dominant group of awake sensors while all other nodes are in a sleep state seems to be a potential way for preserving the energy of these sensor nodes. When the starting energy of the nodes changes from one node to another, this issue becomes more difficult to solve. The notion of a dominant set-in graph has been used in a variety of situations. The search for the smallest dominant set in a big graph might be time-consuming. Specifically, we address two issues: first, identifying the smallest possible dominant set, and second, extending the network lifespan by saving the energy of the sensors. To overcome the first problem, we design and develop a deep learning-based Graph Neural Network (DL-GNN). The GNN training method and back-propagation approach were used to train a GNN consisting of three networks such as transition network, bias network, and output network, to determine the minimal dominant set in the created graph. As a second step, we proposed a hybrid fixed-variant search (HFVS) method that considers minimal dominant sets as input and improves overall network lifespan by swapping nodes of minimal dominating sets. We prepared simulated networks with various network configurations and modeled different WSNs as undirected graphs. To get better convergence, the different values of state vector dimensions of the input vectors are investigated. When the state vector dimension is 3 or 4, minimum dominant set is recognized with high accuracy. The paper also presents comparative analyses between the proposed HFVS algorithm and other existing algorithms for extending network lifespan and discusses the trade-offs that exist between them. Lifespan of wireless sensor network, which is based on the dominant set method, is greatly increased by the techniques we have proposed. 相似文献
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In this paper, we study the survivability in GMPLS optical networks and propose a new algorithm called Protection based on Lightpath Load (PLL) to tolerate the single-fiber link failure. Based on the parameter, Boundary of Heavy-load Lightpath (BHL), PLL can effectively choose the protection execution whether on optical layer or on IP/MPLS layer, such that the bandwidth utilization and recovery complexity can be compromised. In PLL, if the number of Working Label Switching Path (WLSPs) carried on a Working Lightpath (WLP) exceeds the value of BHL, this WLP will be protected in optical layer; otherwise, these WLSPs carried on this WLP will be protected on IP/MPLS layer. Simulation results show that, compared to conventional protection algorithm, PLL not only can significantly reduce the recovery complexity but also can obtain satisfactory trade-off performance. 相似文献
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In this paper, we have presented four variations of applying the same routing algorithm for primary and backup lightpaths, wavelength assignment strategy for survivability. The simulation results show that although everything is the same, yet how and when they are applied leads to variations in results in terms of number of connections accepted. The backup multiplexing technique has been incorporated to reduce the blocking probability in all the strategies. The results have been calculated both for the systems that require 100% degree of survivability, i.e. critical, and for those that do not. The variation to be used depends upon whether the application is critical or not. 相似文献
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A. Khandual N. Rout S.K. Verma P. Patel P. Pattanaik Y. Luximon A. Kumar R.K. Nayak M. Suar 《Materials Today Chemistry》2020
The Nanoparticle (NP) and their oxides are being progressively used and expected to be more frequently used in textiles. Nanoparticle (NP) has higher toxicological risk than larger particles because of their physicochemical properties, chemical reactivity and biological activity. In fact, the stability of nano-oxide particles in the medium is always challenging as they lack functional groups to leverage upon textile materials directly. Thus, in many finishing processes, cross-linkers and/or adhesives are applied together with NP at the cost of inferior comfort, feel and fastness which tends to be toxic and prone to release NPs under common laundering, physical stress and sweat. This study shows that the diffusion of NPs into the fibre polymer matrix via dyeing technique could be much durable, safer in terms of cytotoxicity levels and easy to process for tailoring desired functional attributes. We studied the possibility of a simple application technique via dyeing of vinyl sulphone based reactive dye with four kinds of NPs followed by their cytotoxicity test using cell line A431.1% silica dyed sample have shown highest (198.5%) increase in tensile strength followed by 2% silica and 2% CNT whereas a decrease in elongation is highest in the case of CNT 2% (5.31%) and significantly enhancing the moisture management properties in case of CNT and silica. The study showed promising results in dyeing with TiO2, CNT (Carbon nanotubes), Silica and Alumina NPs in enhancing the mechanical, moisture management, and surface frictional properties to ensure comfortable and safe wear. 相似文献
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GMPLS网络中基于优先级的M : N保护 总被引:1,自引:0,他引:1
给出了一个GMPLS网络中关于广义标签交换通道(G.LSPs)的具有严格优先级M : N保护的排队模型,并通过仿真验证了本模型的正确性.该模型可用于基于优先级的M : N保护设计,通过适当选择保护通道数,可以确保一定的可靠性要求,同时避免过度配置而造成资源浪费. 相似文献
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聚焦长距离无源光网络生存性机制研究,针对单共享风险链路组故障提出一种基于连接可用性的成本有效规划方法.首先,设计了一种基于故障概率的连接可用性模型,计算每个光网络单元的连接可用性.对于不满足连接可用性要求的每个工作光网络单元,为其分配备用光网络单元,其中每个备用光网络单元需要为工作光网络单元预留备用容量.然后,在不同光网络单元之间部署备用光纤,确保每对工作和备用光网络单元之间至少存在一条备用光路径.当一个工作光网络单元因为光纤链路故障而遭遇连接中断时,可将其业务通过备用光路径转移到备用光网络单元承载.通过仿真对所提方法在备用光纤部署成本方面的性能进行了分析.结果表明,该方法能实现比传统邻居保护方法更低的备用光纤部署成本,可解决备用容量分配和备用光纤部署的联合优化问题,在满足连接可用性要求的前提下,通过最小的备用光纤部署成本实现所有业务完全保护. 相似文献
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Design of survivable IP-over-optical networks 总被引:2,自引:0,他引:2
Sylvie Borne Eric Gourdin Bernard Liau A. Ridha Mahjoub 《Annals of Operations Research》2006,146(1):41-73
In the past years, telecommunications networks have seen an important evolution with the advances in optical technologies
and the explosive growth of the Internet. Several optical systems allow a very large transport capacity, and data traffic
has dramatically increased. Telecommunications networks are now moving towards a model of high-speed routers interconnected
by intelligent optical core networks. Moreover, there is a general consensus that the control plan of the optical networks
should utilize IP-based protocols for dynamic provisioning and restoration of lightpaths. The interaction of the IP routers
with the optical core networks permits to achieve end-to-end connections, and the lightpaths of the optical networks define
the topology of the IP network. This new infrastructure has to be sufficiently survivable, so that network services can be
restored in the event of a catastrophic failure. In this paper we consider a multilayer survivable network design problem
that may be of practical interest for IP-over-optical neworks. We give an integer programming formulation for this problem
and discuss the associated polytope. We describe some valid inequalities and study when these are facet defining. We discuss
separation algorithms for these inequalities and introduce some reduction operations. We develop a Branch-and-Cut algorithm
based on these results and present extensive computational results. 相似文献
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