QoE-aware video distribution mechanism in FiWi

The mismatch of transmission ability causes the discontinuous transmission of video services in fiber-wireless access network,aimed at this problem,an QoE-aware video distribution mechanism was proposed.According to the structural characteristics of fiber-wireless access network,link state information and scalable video coding structure was considered,a QoE evaluation mode was established,and the particle swarm optimization algorithm was used to select optimal video transmission rate.Then the node transmission capacity and the node matching degree was analyzed,transmission path for the services was selected,so as to ensure the reliable transmission of services.The results show that the proposed mechanism can effectively improve the utilization rate of network resources and reduce network congestion while improving the quality of the user experience.     

Joint admission control algorithm based on load transfer in heterogeneous networks

A load-transfer-based joint admission control (LJAC) algorithm in heterogeneous networks was proposed.The access requirements of users were admitted based on load balancing,the dynamic load transfer of traffics in the overlapping coverage areas of heterogeneous networks were introduced,and the influence of such factors as the layout of heterogeneous networks and the vertical handoff was considered in the algorithm.The integrated system of heterogeneous networks was modeled as a multidimensional Markov chain,the steady-state probabilities were obtained and the quality of service (QoS) performance metrics were derived.Based on the Poisson point process theory,the upper bound of capacity of the heterogeneous networks satisfying QoS limitations was obtained.The admission control parameters of the integrated system of heterogeneous networks were optimized in order to maximize the resource utilization rate as well as guaranteeing the QoS of users.The simulation results demonstrate lower traffic blocking probability,lower failure probability of vertical handoff requirements,and larger system capacity gain can be achieved by using the proposed LJAC algorithm.     

激光半主动导引头光学系统设计与分析

激光半主动导引头作为一种精确制导的方式,已经在实战中得到广泛的应用。导引头通过对探测器上获取的激光信号进行数据处理以获取目标的位置信息,因此导引头获取激光光斑的能力将会直接影响导引头跟踪目标的性能。本文基于单四象限探测器的工作原理,根据导引头的设计指标,对光学系统的焦距及获取光斑的大小进行分析,应用ZEMAX软件对光学系统进行设计和优化。并从光斑大小、系统畸变和光斑能量分布均匀性等角度对光学系统的性能进行评价。根据评价结果可知该光学系统满足设计要求,获取的光斑质量较好。     

Label‐QoS switching protocol for quality of service assurance in dynamic swarm robot local network

This paper presents the modeling and analysis of a proposed label–quality of service (QoS) switching protocol for heterogeneous robot in a swarm. Establishing the data communication and network in multirobot task allocation is an important aspect in robot collaboration. Instead of passing the data through the cloud network, each robot can be configured as a node in its swarm for intercommunication. This research was conducted to model and propose aggregation and classification methods in a swarm robot network inspired from multiprotocol label switching, namely, label‐QoS switching protocol. Each packet of data is forwarded with a proposed 2‐side label values that are concerned with addressing and QoS. This proposed protocol was applied in each of the node's routing, and it was set up with forwarding information table. The simulation and analysis were conducted in 2 situations: (1) with a constant n–label switch mobile robot and a number of packet data increasing with time and (2) with a constant number of packet and varying n–label switch mobile robot by time. With reference to the network parameter performances, it shows that the anomaly treatment by the proposed protocol is able to prioritize the data forwarding between the robots at the edge of the swarm with class of service although the robot community at the center is increasing or getting crowded.     

Anonymizing region construction scheme based on query range in location-based service privacy protection

Since k-anonymity method can reduce the users’ computation cost and provides the precise query results,it has been widely used to protect the user’s privacy in location-based service.However,the existing schemes did not consider the size of the querying region for location based service provider (LSP) during the construction of the anonymizing region,which led that the quality of service was low.To solve this problem,the user’s querying range was introduced to present a novel anonymizing region construction scheme.In the proposal,the anonymity server first generated the original anonymizing sub-regions according to the user’s privacy requirements,and then merged these sub-regions to construct the anonymity region submitted to LSP based on the size of corresponding querying regions.The security and experiment analysis show that the presented scheme not only protects the user’s privacy effectively,but also decreases LSP’s querying regions,thereby improving the quality of service.     

Deep belief network-based link quality prediction for wireless sensor network

After analyzing the existing link quality prediction models,a link quality prediction model for wireless sensor network was proposed,which was based on deep belief network.Support vector classification was employed to estimate link quality,so as to get link quality levels.Deep belief network was applied in extracting the features of link quality,and softmax was taken to predict the next time link quality.In different scenarios,compared with the model of link quality prediction based on logistic regression,BP neural network and Bayesian network methods,the experimental results show that the proposed prediction model achieves better precision.     

A high precise E-nose for daily indoor air quality monitoring in living environment

E-nose, whose major components include a sensor array and a pattern recognition algorithm, is considered to be a potential way to balance the trade-off between cost and accuracy for daily indoor air quality monitoring in living environment. In this paper, we presented a high precise E-nose for such application. QS-01 from FIS, TGS2600 and TGS2602 from FIGARO, temperature and humidity sensor SHT10 are selected to compose the sensor array. Back Propagation (BP) nueral network, the typical machine learning algorithm is used to be the pattern recognition algorithm of the E-nose. The performance comparison between the proposed E-nose and other E-nose solutions shows the improvement.     

计算机软件可靠性与质量管理的探究

在软件无处不在的现代化社会中,计算机软件可靠性问题是一个非常值得关注的点.若是处于重要位置的计算机软件出现了失误或瘫痪,就会阻碍正常的社会运行,造成巨大的社会经济损失.本文对计算机软件的可靠性定义、评估标准、可靠性测试等概念性问题进行了探究.并在此基础上,从应当加强软件质量管理的观点出发,对计算机软件可靠性的质量管理措施进行了探讨.旨在通过合理科学的计算机软件质量管理来改善计算机软件可靠性问题.     

一种基于DCT系数重组的降参考3D视频质量评价方法

针对3D视频质量评价,提出了一种基于离散余弦变 换(DCT)系数重组的降参考质量评价方法。方法主要 包括4D数据集构造、DCT变换与重组和降参考(RR)质量评价3个阶段。在4D数据集构造阶段 ,通过联合视 频的空间域、视点域和时间域信息构造包含3D视频全部信息的4D数据集;在DCT变换与重 组阶段,首 先对数据集进行DCT变换,然后筛选复杂度较高的DCT系数进行重组,得到能够表征3D视 频质量的重 组系数集;在RR质量评价阶段,首先采用广义高斯分布(GGD)函数对重组后DCT系数集的每 个子带进行建模, 然后利用系数距离函数和频率比距离函数评估3D视频质量。实验结果表明,本文提出的方 法与主观评价结果有较好的相关性,符合人类视觉系统(HVS)。     

基于灰色关联度推理的水质评价系统分析

水质评价是水资源保护和治理过程中一项不可或缺地基础性工作,利用灰色关联分析法对水质进行评价,将实测水质与地表水水质标准进行关联分析,并在传统灰色关联分析法的基础上融合了实例推理技术来构建水质评价系统.首先运用实例推理分析得出实测水质与实例库中已存旧实例水质的相似度值,若相似度值小于阈值系统则会调用灰色关联分析法对该实测水质进行等级评定.系统采用java面向对象语言、MYSQL数据库管理技术设计水质评价系统,通过实验测试,验证了该算法的准确性以及系统的实用性.