共享制造环境下基于Z-RIM的QoS多方异质评价方法

为解决共享制造环境下决策信息异质、候选服务数量动态变化的制造服务QoS评价问题,基于平台、服务需求方、服务提供方的三方决策信息,提出一种符合共享制造特点的QoS多方异质制造服务评价方法。通过精确数、语言变量和Z-number处理异质信息;基于共识最大化计算决策方权重向量,利用TrFWAA算子集结多方信息,依据离差最大化模型计算属性权重;在此基础上,采用RIM对各服务进行评估。结合共享制造环境下的制造业服务优选案例对提出的方法进行验证分析,结果表明该方法具有较好的实用性和优越性。

基于SDN的卫星网络端到端QoS类映射研究

针对在多个卫星网络域环境下域间协作困难,以及如何在各个卫星网络域内选择合适的QoS类实现端到端QoS类映射的问题,基于软件定义卫星网络架构,首先,提出一种SDN卫星网络域间通信方案,以及面向多QoS类的端到端服务交付数据包处理方法。其次,提出一种基于多准则决策的控制模块。模块利用ELECTRE方法,在ELECTRE方法中通过综合权重法计算出各个卫星网络域内QoS指标相应的权重系数,并且利用ELECTRE方法对每个QoS类的净支配指数进行排序,从而为端到端路径的每个卫星网络域选择合适的QoS类。最后,与现有端到端QoS类映射方案进行比较,仿真结果表明,上述方法在多卫星网络域环境下保证端到端的时延、时延抖动、丢包率和代价。

基于遗传-蚁群优化算法的QoS组播路由算法设计

为了提高网络路由性能,提出并设计了一种基于遗传-蚁群优化算法的服务质量(quality of service,QoS)组播路由算法。首先,设计了自适应变频采集策略用于采集网络与节点信息,以此获得网络和节点的状态,为后续路由优化提供数据支持;其次,计算路径代价,将路径代价最小作为优化目标,建立QoS组播路由优化模型,并设置相关约束条件;最后,结合遗传算法和蚁群算法提出一种遗传-蚁群优化算法求解上述模型,输出最优路径,完成路由优化。实验结果表明,所提算法可有效降低路径长度与路径代价,提高搜索效率与路由请求成功率,优化后的路由时延抖动较小。

基于QoS约束的通信组网链路故障恢复探究

随着网络技术的不断发展,通信网的规模逐渐扩大,网络结构日渐趋于复杂化,发生故障的概率自然就会增高。当通信网出现故障后,必须尽快恢复,否则可能会造成巨大的经济损失,严重时甚至引发各类社会安全风险。智能通信网是解决上述问题的有效策略之一,对网络带宽、时延、丢包率提出了不同的要求。本文对如何恢复网络故障展开了研究,提出了一种基于QoS(Quality of Service)约束的通信组网链路故障恢复方法,根据用户对业务提出的QoS需求以及空闲网络资源,选择恢复路径,确保传输业务的可靠性。在当通信网发生故障后,该方法能够有针对性地快速解决故障,对通信技术的应用与发展具有实用价值。

云服务推荐中基于多源特征和多任务学习的时序QoS预测

随着云计算技术的普及,云服务数量指数级增长,用户不再满足于功能性需求,服务质量(Quality of Service,QoS)成为比较服务优劣的关键性能指标.如何在动态、复杂的云环境中实时、准确地预测服务质量并为用户推荐高质量服务成为热点问题.考虑到云服务器的负载、网络状态、用户接入云环境的偏好等随着时间变化,本文提出了基于多源特征和多任务学习的时序QoS预测方法(T-MST),它可以实时、准确地同时预测多种QoS属性.首先,TMST对用户、服务进行特征表示,通过Time2Vec刻画时序特征,再结合多种QoS属性的历史记录生成多源特征表示.其次,基于滑动窗口采用LSTM感知窗口内的时序关系,借助注意力机制细化窗口内不同时刻的关键性,从而构造待预测时刻的隐藏状态.最后,T-MST采用多任务预测层实现多种QoS属性的同时预测,它们共享上游模型,仅在预测层采用不同的感知模块以提升模型的鲁棒性和计算效率.本文基于真实世界的数据集进行了全面的实验验证,结果表明T-MST在吞吐量和响应时间的时序预测任务上平均绝对误差(Mean Absolute Error,MAE)分别平均提升了37.53%和20.38%,优于现有的时序QoS预测方法;而且TMST的计算效率更高,能够有效应对实时QoS预测的需求.

Collaborative positioning for swarms:A brief survey of vision,LiDAR and wireless sensors based methods

As positioning sensors,edge computation power,and communication technologies continue to develop,a moving agent can now sense its surroundings and communicate with other agents.By receiving spatial information from both its environment and other agents,an agent can use various methods and sensor types to localize itself.With its high flexibility and robustness,collaborative positioning has become a widely used method in both military and civilian applications.This paper introduces the basic fundamental concepts and applications of collaborative positioning,and reviews recent progress in the field based on camera,LiDAR(Light Detection and Ranging),wireless sensor,and their integration.The paper compares the current methods with respect to their sensor type,summarizes their main paradigms,and analyzes their evaluation experiments.Finally,the paper discusses the main challenges and open issues that require further research.

Rao Algorithms-Based Structure Optimization for Heterogeneous Wireless Sensor Networks

The structural optimization of wireless sensor networks is a critical issue because it impacts energy consumption and hence the network’s lifetime.Many studies have been conducted for homogeneous networks,but few have been performed for heterogeneouswireless sensor networks.This paper utilizes Rao algorithms to optimize the structure of heterogeneous wireless sensor networks according to node locations and their initial energies.The proposed algorithms lack algorithm-specific parameters and metaphorical connotations.The proposed algorithms examine the search space based on the relations of the population with the best,worst,and randomly assigned solutions.The proposed algorithms can be evaluated using any routing protocol,however,we have chosen the well-known routing protocols in the literature:Low Energy Adaptive Clustering Hierarchy(LEACH),Power-Efficient Gathering in Sensor Information Systems(PEAGSIS),Partitioned-based Energy-efficient LEACH(PE-LEACH),and the Power-Efficient Gathering in Sensor Information Systems Neural Network(PEAGSIS-NN)recent routing protocol.We compare our optimized method with the Jaya,the Particle Swarm Optimization-based Energy Efficient Clustering(PSO-EEC)protocol,and the hybrid Harmony Search Algorithm and PSO(HSA-PSO)algorithms.The efficiencies of our proposed algorithms are evaluated by conducting experiments in terms of the network lifetime(first dead node,half dead nodes,and last dead node),energy consumption,packets to cluster head,and packets to the base station.The experimental results were compared with those obtained using the Jaya optimization algorithm.The proposed algorithms exhibited the best performance.The proposed approach successfully prolongs the network lifetime by 71% for the PEAGSIS protocol,51% for the LEACH protocol,10% for the PE-LEACH protocol,and 73% for the PEGSIS-NN protocol;Moreover,it enhances other criteria such as energy conservation,fitness convergence,packets to cluster head,and packets to the base station.

Improved Flexible Triboelectric Nanogenerator Based on Tile-Nanostructure for Wireless Human Health Monitor

Triboelectric nanogenerators(TENGs)have emerged as promising candidates for integrating with flexible electronics as self-powered systems owing to their intrinsic flexibility,biocompatibility,and miniaturization.In this study,an improved flexible TENG with a tile-nanostructured MXene/polymethyl methacrylate(PMMA)composite electrode(MP-TENG)is proposed for use in wireless human health monitor.The multifunctional tile-nanostructured MXene/PMMA film,which is self-assembled through vacuum filtration,exhibits good conductivity,excellent charge capacity,and high flexibility.Thus,the MXene/PMMA composite electrode can simultaneously function as a charge-generating,charge-trapping,and charge-collecting layer.Furthermore,the charge-trapping capacity of a tile nanostructure can be optimized on the basis of the PMMA concentration.At a mass fraction of 4%PMMA,the MP-TENG achieves the optimal output performance,with an output voltage of 37.8 V,an output current of 1.8μA,and transferred charge of 14.1 nC.The output power is enhanced over twofold compared with the pure MXene-based TENG.Moreover,the MP-TENG has sufficient power capacity and durability to power small electronic devices.Finally,a wireless human motion monitor based on the MP-TENG is utilized to detect physiological signals in various kinematic motions.Consequently,the proposed performance-enhanced MP-TENG proves a considerable potential for use in health monitoring,telemedicine,and self-powered systems.

基于SDN的空间信息网络自适应QoS路由算法的设计与实现

为了满足用户对网络服务质量的要求,本文提出一种基于SDN的空间信息网络自适应QoS路由算法。该算法采用SDN控制器对网络进行全局控制和管理,通过收集网络拓扑信息和质量参数,动态调整路由策略,实现网络的自适应QoS路由。实验结果表明,该算法能够有效提高网络服务质量,优化网络性能。

Ultraconformable Integrated Wireless Charging Micro-Supercapacitor Skin

Conformable and wire-less charging energy storage devices play important roles in enabling the fast development of wearable,non-contact soft electronics.However,current wire-less charging power sources are still restricted by limited flexural angles and fragile connection of components,resulting in the failure expression of performance and constraining their fur-ther applications in health monitoring wearables and moveable artificial limbs.Herein,we present an ultracompatible skin-like integrated wireless charging micro-supercapacitor,which building blocks(including electrolyte,electrode and substrate)are all evaporated by liquid precursor.Owing to the infiltration and permeation of the liquid,each part of the integrated device attached firmly with each other,forming a compact and all-in-one configuration.In addition,benefitting from the controllable volume of electrode solution precursor,the electrode thickness is easily regulated varying from 11.7 to 112.5μm.This prepared thin IWC-MSC skin can fit well with curving human body,and could be wireless charged to store electricity into high capacitive micro-supercapacitors(11.39 F cm-3)of the integrated device.We believe this work will shed light on the construction of skin-attachable electronics and irregular sensing microrobots.

Highly Flexible Graphene-Film-Based Rectenna for Wireless Energy Harvesting

Herein,we report the design,fabrication,and performance of two wireless energy harvesting devices based on highly flexible graphene macroscopic films(FGMFs).We first demonstrate that benefiting from the high conductivity of up to 1×10^(6)S m^(-1)and good resistive stability of FGMFs even under extensive bending,the FGMFs-based rectifying circuit(GRC)exhibits good flexibility and RF-to-DC efficiency of 53%at 2.1 GHz.Moreover,we further expand the application of FGMFs to a flexible wideband monopole rectenna and a 2.45 GHz wearable rectenna for harvesting wireless energy.The wideband rectenna at various bending conditions produces a maximum conversion efficiency of 52%,46%,and 44%at the 5th Generation(5G)2.1 GHz,Industrial Long-Term Evolution(LTE)2.3 GHz,and Scientific Medical(ISM)2.45 GHz,respectively.A 2.45 GHz GRC is optimized and integrated with an AMC-backed wearable antenna.The proposed 2.45 GHz wearable rectenna shows a maximum conversion efficiency of 55.7%.All the results indicate that the highly flexible graphene-film-based rectennas have great potential as a wireless power supplier for smart Internet of Things(loT)applications.

UAV-assisted data collection for wireless sensor networks with dynamic working modes

Wireless Sensor Network(WSN)is a cornerstone of Internet of Things(IoT)and has rich application scenarios.In this work,we consider a heterogeneous WSN whose sensor nodes have a diversity in their Residual Energy(RE).In this work,to protect the sensor nodes with low RE,we investigate dynamic working modes for sensor nodes which are determined by their RE and an introduced energy threshold.Besides,we employ an Unmanned Aerial Vehicle(UAV)to collect the stored data from the heterogeneous WSN.We aim to jointly optimize the cluster head selection,energy threshold and sensor nodes’working mode to minimize the weighted sum of energy con-sumption from the WSN and UAV,subject to the data collection rate constraint.To this end,we propose an efficient search method to search for an optimal energy threshold,and develop a penalty-based successive convex approximation algorithm to select the cluster heads.Then we present a low-complexity iterative approach to solve the joint optimization problem and discuss the implementation procedure.Numerical results justify that our proposed approach is able to reduce the energy consumption of the sensor nodes with low RE significantly and also saves energy for the whole WSN.

星地异构网络联合QoS保障关键技术

针对星地异构网络的拓扑结构高动态、星地链路高差异、网络资源强受限等特征给星地融合业务高效承载带来重大挑战的问题,深入分析星地异构网络发展现状,提出星地异构网络联合QoS保障系统架构。并在此基础上,针对跨域资源统一编排管理、星地联合QoS指标参考体系构建、联合QoS动态策略调控、星地资源按需适配与部署等关键技术进行探讨。

云联盟三层架构:博弈型QoS建模

面对国内外大型公有云供应商的激烈竞争,中小云厂商的生存难度加大。为此,建立一个基于相互合作的云联盟成为了这些厂商的一种可行策略。然而,在追求个体最大利益和保障联盟整体服务质量(quality of service,QoS)之间存在着复杂的博弈关系。针对上述问题,一种基于QoS的云联盟模型被提出,其涵盖云计算的三层架构。在应用层至虚拟层,引入了一种基于差分进化(differential evolution,DE)算法的创新任务分配策略,专门用于处理多QoS任务分配问题。在虚拟层至物理层,设计了合作与竞争并存的虚拟机迁移模型,适用于在云联盟博弈计算环境下实现虚拟机迁移的能耗与QoS之间的平衡。实验结果表明,所提出的解决方案改进了云计算环境的服务质量,并揭示了在云联盟环境中,合作和竞争两种模式的相对优势。

5G-R调度通信QoS协商和业务流程设计

随着铁路发展,移动通信业务需求不断增加,同时,移动通信技术迭代创新,铁路亟待发展新一代宽带移动通信系统(5G-R)。调度通信业务是5G-R承载的重要业务,为规范业务流程,明确设备要求,保证设备互联互通,需研究调度通信QoS协商和业务流程。首先,研究5G-R调度通信业务需求和系统架构;其次,研究QoS控制管理方式,提出基于N5接口动态协商QoS机制,研究N5接口服务架构和服务操作;然后,重点研究语音、视频个呼、组呼等典型业务流程,研究功能寻址和位置寻址业务实现方案,提出N5接口技术要求;最后,依托研发实验室进行测试验证。试验表明,业务流程和实现方案技术上可行性,实现了功能扩展,性能明显提升,个呼建立时间从不大于10 s减少为2.65 s,且基于N5接口动态协商QoS机制能够保障业务优先级,实现不同厂家设备互联互通。建议结合试验线进一步优化业务流程。

Wi-Fi QoS技术综合分析

为了满足对高带宽、低时延业务的服务质量要求,Wi-Fi技术必须支持不同类型业务质量的管理机制。首先,分析传统Wi-Fi QoS技术面临的挑战,阐述Wi-Fi联盟弥补传统的Wi-Fi多媒体功能WMM不足而定义的QoS管理技术,有效支持下行数据流的分类和优先级设定;其次,进一步分析和介绍Wi-Fi7对于QoS改进的关键技术,包括数据流的QoS特征识别技术和严格目标唤醒时间r-TWT技术,以及二者结合对于低时延业务的支持;最后,对Wi-Fi的QoS技术发展进行小结和展望。

基于QoS-QoE预测的传输瓶颈定位

在实时音视频传输中,QoS指标反映服务端可感知的网络情况,QoE指标直接体现用户侧对视频业务的满意程度,尽管QoE指标是服务提供商更为关注的指标,但是由于接口适配和用户隐私保护等问题,云服务提供商往往不能实时获得QoE数据,因此无法及时对可能发生的QoE异常进行预测并采取优化措施。由于QoS-QoE存在一定映射关系,提出一种基于服务端的QoS指标实现对QoE指标进行瓶颈检测的模型,可以减少运维人员定位的工作量,提高网络优化效率。模型使用不平衡决策树进行QoS-QoE预测,实现QoE异常检测。使用LSTM回归模型进行因果分析,实现瓶颈定位。实验表明该模型对QoE异常检测有较高准确率,并且可以发掘传输过程中对传输结果影响较大的QoS指标。

基于改进和声搜索的配电网WSNs多路径QoS路由算法

针对智能配电网(Smart distribution network,SDN)中无线通信数据传输不可靠且网络寿命低等问题,提出一种基于改进和声搜索的无线传感器网络(Wireless sensor networks,WSNs)多路径QoS路由算法(Multipath QoS routing algorithm,MQRA)。首先,分析配电网的通信需求并建立数据传输模型;然后,针对无线传感器路由问题的特点对和声搜索算法(Harmony search,HS)做出改进;再将其自适应参数公式进行改进以避免算法陷入局部最优;通过在源节点与目的节点之间构建前传区域来优化转发节点集以避免数据回传,提升算法的运行效率;最后,在初始和声库生成阶段,综合考虑距离、丢包率以及节点剩余能量来改进轮盘法中的概率公式。仿真结果表明MQRA算法能有效降低数据传输的时延,提升数据可靠性并均衡节点能耗延长网络使用寿命。

QoS数据不确定性下电力业务服务自适应选取模型

针对电力业务服务选取不可靠,造成用户服务质量不佳的问题,构建了QoS数据不确定性下电力业务服务自适应选取模型。通过局部约简处理方法,调整搜索空间,计算约束满意度的自适应值,采用动态适应性函数和惩罚函数进行服务寻优。充分考虑QoS数据不确定性,设计电力业务服务自适应选取流程。依据QoS属性,构建基于响应时间的自适应选取云模型,通过计算属性云期望值、熵值、随机性及反馈相似度实现电力业务服务自适应选取。由实验结果可知,该模型的用户满意度最大值为88%,计算时间最大值为0.69 s,能够有效提升电力业务服务质量。

Highlights in recent wireless power IC research

Wireless power transfer(WPT)has been a popular topic in power integrated circuit(IC)designs in the past decade.As slogan"cutting the last wire"presented in ISSCC’15[1],WPT is poised to take over many wired power deliveries applica-tions today,just like what happened to wireless communica-tion nowadays.Over the years,WPT has become more mature and more wirelessly charged or powered products have become available on the market.This mini review intends to summarize recent breakthroughs in WPT inte-grated circuits(IC)research.