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Quality of Service and Security on Cisco Network Devices, Coupled with the Development of a Mobile Application Prototype Software for Server Room Temperature Monitoring
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作者 Desire Mudenda Charles Smart Lubobya 《Journal of Computer and Communications》 2024年第8期123-140,共18页
In an era where digital technology is paramount, higher education institutions like the University of Zambia (UNZA) are employing advanced computer networks to enhance their operational capacity and offer cutting-edge... In an era where digital technology is paramount, higher education institutions like the University of Zambia (UNZA) are employing advanced computer networks to enhance their operational capacity and offer cutting-edge services to their academic fraternity. Spanning across the Great East Road campus, UNZA has established one of the most extensive computer networks in Zambia, serving a burgeoning community of over 20,000 active users through a Metropolitan Area Network (MAN). However, as the digital landscape continues to evolve, it is besieged with burgeoning challenges that threaten the very fabric of network integrity—cyber security threats and the imperatives of maintaining high Quality of Service (QoS). In an effort to mitigate these threats and ensure network efficiency, the development of a mobile application to monitor temperatures in the server room was imperative. According to L. Wei, X. Zeng, and T. Shen, the use of wireless sensory networks to monitor the temperature of train switchgear contact points represents a cost-effective solution. The system is based on wireless communication technology and is detailed in their paper, “A wireless solution for train switchgear contact temperature monitoring and alarming system based on wireless communication technology”, published in the International Journal of Communications, Network and System Sciences, vol. 8, no. 4, pp. 79-87, 2015 [1]. Therefore, in this study, a mobile application technology was explored for monitoring of temperatures in the server room in order to aid Cisco device performance. Additionally, this paper also explores the hardening of Cisco device security and QoS which are the cornerstones of this study. 展开更多
关键词 quality of service (qos) Network Security Temperature Monitoring Mobile Application Cisco Devices
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Web services composition with QoS bound based on simulated annealing algorithm 被引量:6
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作者 刘青 张世龙 +1 位作者 杨锐 连祥鉴 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期308-311,共4页
In order to enable quality-aware web services selection in the process of service composition,this paper first describes the non-functional requirements of service consumers and the quality of elementary service or co... In order to enable quality-aware web services selection in the process of service composition,this paper first describes the non-functional requirements of service consumers and the quality of elementary service or composite service as a quality vector,and then models the QoS(quality of service)-aware composition as a multiple criteria optimization problem in extending directed graph.A novel simulated annealing algorithm for QoS-aware web services composition is presented.A normalizing for composite service QoS values is made,and a secondary iterative optimization is used in the algorithm.Experimental results show that the simulated annealing algorithm can satisfy the multiple criteria and global QoS requirements of service consumers.The algorithm produces near optimum solution with much less computation cost. 展开更多
关键词 web services quality of serviceqos service composition simulated annealing
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Modeling and performance evaluation of QoS-aware job scheduling of computational grids
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作者 单志广 林闯 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期425-430,共6页
To achieve high quality of service (QoS) on computational grids, the QoS-aware job scheduling is investigated for a hierarchical decentralized grid architecture that consists of multilevel schedulers. An integrated ... To achieve high quality of service (QoS) on computational grids, the QoS-aware job scheduling is investigated for a hierarchical decentralized grid architecture that consists of multilevel schedulers. An integrated QoS-aware job dispatching policy is proposed, which correlates priorities of incoming jobs used for job selecting at the local scheduler of the grid node with the job dispatching policies at the global scheduler for computational grids. The stochastic high-level Petri net (SHLPN) model of a two-level hierarchy computational grid architecture is presented, and a model refinement is made to reduce the complexity of the model solution. A performance analysis technique based on the SHLPN is proposed to investigate the QoS-aware job scheduling policy. Numerical results show that the QoS-aware job dispatching policy outperforms the QoS-unaware job dispatching policy in balancing the high-priority jobs, and thus enables priority-based QoS. 展开更多
关键词 computational grids job scheduling quality of service qos performance evaluation MODELING stochastic high-level Petri net (SHLPN)
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Approach of service recovery decision-making based on Bellman dynamic programming
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作者 何蕾 任江春 王志英 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期377-380,共4页
Based on service-oriented architecture(SOA),a Bellman-dynamic-programming-based approach of service recovery decision-making is proposed to make valid recovery decisions.Both the attribute and the process of service... Based on service-oriented architecture(SOA),a Bellman-dynamic-programming-based approach of service recovery decision-making is proposed to make valid recovery decisions.Both the attribute and the process of services in the controllable distributed information system are analyzed as the preparatory work.Using the idea of service composition as a reference,the approach translates the recovery decision-making into a planning problem regarding artificial intelligence (AI) through two steps.The first is the self-organization based on a logical view of the network,and the second is the definition of evaluation standards.Applying Bellman dynamic programming to solve the planning problem,the approach offers timely emergency response and optimal recovery source selection,meeting multiple QoS (quality of service)requirements.Experimental results demonstrate the rationality and optimality of the approach,and the theoretical analysis of its computational complexity and the comparison with conventional methods exhibit its high efficiency. 展开更多
关键词 service recovery decision-making Bellman dynamic programming quality of service qos service-oriented architecture(SOA)
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Trustworthy Assurance of Service Interoperation in Cloud Environment 被引量:6
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作者 Bing Li Bu-Qing Cao +1 位作者 Kun-Mei Wen Rui-Xuan Li 《International Journal of Automation and computing》 EI 2011年第3期297-308,共12页
Cloud computing can be realized by service interoperation and its essence is to provide cloud services through network. The development of effective methods to assure the trustworthiness of service interoperation in c... Cloud computing can be realized by service interoperation and its essence is to provide cloud services through network. The development of effective methods to assure the trustworthiness of service interoperation in cloud environment is a very important problem. The essence of cloud security is trust and trust management. Combining quality of service (QoS) with trust model, this paper constructs a QoS-aware and quantitative trust-model that consists of initial trust value, direct trust value, and recommendatory trust value of service, making the provision, discovery, and aggregation of cloud services trustworthy. Hence, it can assure trustworthiness of service interoperation between users and services or among services in cloud environment. At the same time, based on this model, service discovery method based on QoS-aware and quantitative trust-model (TQoS-WSD) is proposed, which makes a solid trust relationship among service requestor, service provider and service recommender, and users can find trustworthy service whose total evaluation value is higher. Corapared to QoS-based service discovery (QoS-WSD) method, it is proved by the experiment for TQoS-WSD method that more accurate result of service discovery will be achieved by service requestor, while reasonable time cost is increased. Meanwhile, TQoS-WSD method strongly resists the effect of service discovery by untrustworthy QoS values and improves service invocation success-rate and thus assures trustworthiness of services interoperation. 展开更多
关键词 quality of service qos trust service discovery service interoperation service invocation success-rate cloud computing.
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Interactive Web service choice-making based on extended QoS model 被引量:3
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作者 MOU Yu-jie CAO Jian ZHANG Shen-sheng ZHANG Jian-hong 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第4期483-492,共10页
Quality of Service (QoS) is a key factor in Web service advertising, choosing and runtime monitoring. Web service QoS is multi-faceted, fuzzy and dynamic. Current researches focus on implementation level performance a... Quality of Service (QoS) is a key factor in Web service advertising, choosing and runtime monitoring. Web service QoS is multi-faceted, fuzzy and dynamic. Current researches focus on implementation level performance assurance, ignoring domain specific or application level metrics which are also very important to service users. Industry Web service standards lack QoS expression. The support for QoS based service choice-making is very limited. We proposed an extended Web service QoS model based on configurable fuzzy synthetic evaluation system. Web service QoS is evaluated dynamically according to the service context. A QoS requirement description model is also given for service QoS requirement definition. An interactive Web service choice-making process is described, which takes QoS as a key factor when choosing from functionally equivalent services. 展开更多
关键词 quality of service qos Web service Choice-making Fuzzy synthetic evaluation
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Autonomic QoS Management Mechanism in Software Defined Network 被引量:3
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作者 WANG Wendong QI Qinglei GONG Xiangyan HU Yannan QUE Xirong 《China Communications》 SCIE CSCD 2014年第7期13-23,共11页
With the increase of network complexity,the flexibility of network control and management becomes a nontrivial problem.Both Software Defined Network(SDN) and Autonomic Network technologies are sophisticated technologi... With the increase of network complexity,the flexibility of network control and management becomes a nontrivial problem.Both Software Defined Network(SDN) and Autonomic Network technologies are sophisticated technologies for the network control and management.These two technologies could be combined together to construct a software defined self-managing solution for the future network.An autonomic QoS management mechanism in Software Defined Network(AQSDN) is proposed in this paper.In AQSDN,the various QoS features can be configured autonomically in an OpenFlow switch through extending the OpenFlow and OF-Config protocols.Based on AQSDN,a novel packet context-aware QoS model(PCaQoS) is also introduced for improving the network QoS.PCaQoS takes packet context into account when packet is marked and managed into forwarding queues.The implementation of a video application's prototype which evaluates the self-configuration feature of the AQSDN and the enhancement ability of the PCaQoS is presented in order to validate this design. 展开更多
关键词 software defined network autonomic management context aware quality of service qos
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A QoS-aware vertical handoff algorithm based on predictive network information 被引量:3
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作者 郭云松 谭冠政 +1 位作者 A.S.M.LIBDA 马丽强 《Journal of Central South University》 SCIE EI CAS 2012年第8期2187-2193,共7页
In converged heterogeneous wireless networks, vertical handoff is an important issue in radio resource management and occurs when an end user switches from one network to another (e.g., from wireless local area netwo... In converged heterogeneous wireless networks, vertical handoff is an important issue in radio resource management and occurs when an end user switches from one network to another (e.g., from wireless local area network to wideband code division multiple access). Efficient vertical handoff should allocate network resources efficiently and maintain good quality of service (QoS) for the end users. The objective of this work is to determine conditions under which vertical handoff can be performed. The channel usage situation of each access network is formulated as a birth-death process with the objective of predicting the avaliable bandwidth and the blocking probability. A reward function is used to capture the network bandwidth and the blocking probability is expressed as a cost function. An end user will access the certain network which maximizes the total function defined as the combination of the reward fimction and the cost function. Simulation results show that the proposed algorithm can significantly improve the network performance, including higher bandwidth for end users and lower new call blocking and handoff call blocking probability for networks. 展开更多
关键词 heterogeneous wireless network vertical handoff quality of service qos birth-death process
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Service allocation based on QoS evaluation in military organization cloud cooperation 被引量:3
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作者 An Zhang Haiyang Sun Yanxia Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第2期386-394,共9页
The problem of cloud cooperation of military service providers(MSPs) is addressed for allocating limited resources to military service users(MSUs) that are geographically distributed. The MSPs, also called militar... The problem of cloud cooperation of military service providers(MSPs) is addressed for allocating limited resources to military service users(MSUs) that are geographically distributed. The MSPs, also called military organization clouds, are virtualized and encapsulated by the services they can offer and each of them contains different kinds of resources that MSU needs. The MSPs are also geographically dispersed. They are required to allocate their resources to the MSU complying with the corresponding quality of service(QoS), so that each MSU gathers the services it needs to guarantee its task to be implemented. The outline of military organization cloud cooperation is discussed and the method of service optimal selection is proposed based on QoS evaluation. The QoS evaluation method based on exponential approximation is put forward to include the users' will. Simulation results verify the effectiveness of the proposed algorithm. 展开更多
关键词 service allocation quality of service(Qo S) cloud cooperation
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An approach for QoS measurement and web service selection sureness 被引量:1
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作者 Shariq Hussain Wang Zhaoshun Ibrahima Kalil Toure 《High Technology Letters》 EI CAS 2013年第3期283-289,共7页
Web services have gained popularity m recent years anu prowue a new moue, u~ w^u, w,,,~,, ,^- cilitates interaction of scientific and business applications through the Internet. More often, several services with simil... Web services have gained popularity m recent years anu prowue a new moue, u~ w^u, w,,,~,, ,^- cilitates interaction of scientific and business applications through the Internet. More often, several services with similar functionality are available from a large and changing number of service provid- ers. Quality of Service (QoS) is the dominant factor in service selection and is of great importance to users. In this paper, we propose a model for QoS measurement and web services selection. The model consists of QoS model, QoS monitoring, QoS comparison and service selection with a QoS feedback mechanism. The most suitable service is to take into account the agreed QoS, monitoring is done during invocation phase and if any deviation is recorded, next suitable service is selected. Fi- nally the model is proved to be feasible and effective by simulation experiments. 展开更多
关键词 web services quality of service qos qos measurement RANKING web serviceselection
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Trust assessment of business service workflow based on complex trust network 被引量:1
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作者 骆怡航 Fan Yushun Guo Xiaohui 《High Technology Letters》 EI CAS 2015年第1期22-30,共9页
For business service workflow,QoS-based services selection can't guarantee whether the composite service satisfies user' s requirement after delivery,because once any service interrupts or quality of service(Q... For business service workflow,QoS-based services selection can't guarantee whether the composite service satisfies user' s requirement after delivery,because once any service interrupts or quality of service(QoS) maliciously reduces,the quality of workflow will be reduced.Trustworthy services can provide reliable QoS,so trustworthiness research could improve the efficiency of services selection.This paper investigates trust assessment in the perspective of workflow.Firstly,trust network of business service workflow(TN-BSW) is proposed to analyze trust attributes;then,the trust measurement system of TN-BSW is investigated to assess the trust value quantitatively;and then,a trust-aware service recommendation model(TaSRM) is proposed to enhance the efficiency of QoS-basedservices selection;finally,experiment shows the feasibility of TN-BSWand the performance of TaSRM. 展开更多
关键词 business service workflow trust attributes trust assessment quality of service qos service selection
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A DELAY BASED BACKOFF SCHEME FOR WLAN WITH QoS GUARANTEE AND ITS PERFORMANCE 被引量:1
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作者 LiXiaohui KouWeidong +1 位作者 LiuNai'an YiKechu 《Journal of Electronics(China)》 2005年第4期416-421,共6页
Based on the Distributed Coordination Function (DCF) and the Enhanced DCF (EDCF) mechanisms in IEEE 802.11 and 802.11e, a novel backoff scheme for Wireless Local Area Network (WLAN) is proposed. The scheme is to solve... Based on the Distributed Coordination Function (DCF) and the Enhanced DCF (EDCF) mechanisms in IEEE 802.11 and 802.11e, a novel backoff scheme for Wireless Local Area Network (WLAN) is proposed. The scheme is to solve the problem of the packet loss and the decrease of performance due to the increasing Contention Window (CW) when there are continuous collisions. In the proposed scheme, the CW of the packet will change dynamically with different delay for the different traffics. Mathematic formulas are presented to indicate the relationship between the CW and the delay character. ,The performance of the new scheme is also discussed with simulation results. The results show that it helps WLAN system handle multimedia simultaneously. 展开更多
关键词 Wireless Local Area Network (WLAN) Distributed Coordination Function (DCF) BACKofF quality of service (qos)
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NEW ARCHITECTURE OF IP QOS MANAGEMENT SYSTEM
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作者 Jiao Li Cui Yidong Lin Yu Wang Wendong Cheng Shiduan 《Journal of Electronics(China)》 2006年第4期580-583,共4页
Based on the analysis of current Quality of Service (QoS) management on IP network, new genera-tion of QoS architecture QoSAF is proposed. QoSAF is divided into three layers: resource control layer, net-work service l... Based on the analysis of current Quality of Service (QoS) management on IP network, new genera-tion of QoS architecture QoSAF is proposed. QoSAF is divided into three layers: resource control layer, net-work service layer and business layer. QoS management is accomplished by interactivity of layers. In this ar-chitecture, mechanism of feedback control enhances the functions of resource management and system moni-toring. The principle of design and logical architecture of system is discussed in detail. 展开更多
关键词 quality of service qos qos architecture Closed feedback loop
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An efficient QoS enhancement mechanism of VoIP using erasure array codes
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作者 李真 Zhang Qin +2 位作者 Ren Hui Liu Wenbo Gao Xinyan 《High Technology Letters》 EI CAS 2017年第4期390-398,共9页
In order to solve the problem of losing voice packets in voice over internet protocol(VoIP),a kind of lost packets double recovery algorithm is proposed. The algorithm is based on erasure coding technique which comes ... In order to solve the problem of losing voice packets in voice over internet protocol(VoIP),a kind of lost packets double recovery algorithm is proposed. The algorithm is based on erasure coding technique which comes from highly available data storage systems. An efficient coding scheme with higher tolerance based on STAR and Reed-Solomon( RS) erasure code is described. An efficient method is also provided which could transform the voice data packets of one dimensional bit stream into two dimensional array according to given window size. If the lost rate has increased beyond the error correction capability,packet-loss concealment will be adopted. Under various conditions of packet-loss simulation during the experiments,the algorithm has proved its better performance on MOS rating and coding rate. 展开更多
关键词 packet loss recovery voice over internet protocol(VoIP) quality of service(qos) array code
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BFS-SVM Classifier for QoS and Resource Allocation in Cloud Environment
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作者 A.Richard William J.Senthilkumar +1 位作者 Y.Suresh V.Mohanraj 《Computer Systems Science & Engineering》 SCIE EI 2023年第10期777-790,共14页
In cloud computing Resource allocation is a very complex task.Handling the customer demand makes the challenges of on-demand resource allocation.Many challenges are faced by conventional methods for resource allocatio... In cloud computing Resource allocation is a very complex task.Handling the customer demand makes the challenges of on-demand resource allocation.Many challenges are faced by conventional methods for resource allocation in order tomeet the Quality of Service(QoS)requirements of users.For solving the about said problems a new method was implemented with the utility of machine learning framework of resource allocation by utilizing the cloud computing technique was taken in to an account in this research work.The accuracy in the machine learning algorithm can be improved by introducing Bat Algorithm with feature selection(BFS)in the proposed work,this further reduces the inappropriate features from the data.The similarities that were hidden can be demoralized by the Support Vector Machine(SVM)classifier which is also determine the subspace vector and then a new feature vector can be predicted by using SVM.For an unexpected circumstance SVM model can make a resource allocation decision.The efficiency of proposed SVM classifier of resource allocation can be highlighted by using a singlecell multiuser massive Multiple-Input Multiple Output(MIMO)system,with beam allocation problem as an example.The proposed resource allocation based on SVM performs efficiently than the existing conventional methods;this has been proven by analysing its results. 展开更多
关键词 Bat algorithm with feature selection(BFS) support vector machine(SVM) multiple-input multiple output(MIMO) quality of service(qos) CLASSIFIER cloud computing
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QoS-based MAC protocol for cognitive radio networks 被引量:2
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作者 胡静 沈连丰 宋铁成 《Journal of Southeast University(English Edition)》 EI CAS 2012年第4期375-379,共5页
In order to improve the throughput performance of the secondary users (SUs) in the cognitive radio (CR) environment, a quality of service (QoS) based media access control (MAC) protocol is proposed. In this pr... In order to improve the throughput performance of the secondary users (SUs) in the cognitive radio (CR) environment, a quality of service (QoS) based media access control (MAC) protocol is proposed. In this protocol, the CR node maps the channel state as a vector, and the transmitter and the receiver obtain the final channel map through an AND operation to prepare for an optional channel set. Data from the upper application layer are classified into two priority levels according to the QoS requirement. The data of each level relate to different contention windows so that the priority of real time data can be guaranteed. A two-dimensional discrete-time Markov chain is utilized to evaluate the system performance, and mathematical expressions of the system throughput are derived. Simulation results show that compared with the IEEE 802. 11 distributed coordination function (DCF), the proposed MAC protocol can achieve higher throughput. 展开更多
关键词 quality of service qos cognitive radio media access control (MAC) channel map Markov chain
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SI-INSPIRED ENERGY AWARE QoS ROUTING TREE FOR WSN
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作者 黄如 朱煜 +1 位作者 苗澎 朱杰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第2期192-198,共7页
A heuristic theoretical optimal routing algorithm (TORA) is presented to achieve the data-gathering structure of location-aided quality of service (QoS) in wireless sensor networks (WSNs). The construction of TO... A heuristic theoretical optimal routing algorithm (TORA) is presented to achieve the data-gathering structure of location-aided quality of service (QoS) in wireless sensor networks (WSNs). The construction of TORA is based on a kind of swarm intelligence (SI) mechanism, i. e. , ant colony optimization. Firstly, the ener- gy-efficient weight is designed based on flow distribution to divide WSNs into different functional regions, so the routing selection can self-adapt asymmetric power configurations with lower latency. Then, the designs of the novel heuristic factor and the pheromone updating rule can endow ant-like agents with the ability of detecting the local networks energy status and approaching the theoretical optimal tree, thus improving the adaptability and en- ergy-efficiency in route building. Simulation results show that compared with some classic routing algorithms, TORA can further minimize the total communication energy cost and enhance the QoS performance with low-de- lay effect under the data-gathering condition. 展开更多
关键词 wireless sensor networks (WSNs) swarm intelligence (SI) ROUTING energy aware quality of serviceqos
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New Antenna Array Beamforming Techniques Based on Hybrid Convolution/Genetic Algorithm for 5G and Beyond Communications
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作者 Shimaa M.Amer Ashraf A.M.Khalaf +3 位作者 Amr H.Hussein Salman A.Alqahtani Mostafa H.Dahshan Hossam M.Kassem 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2749-2767,共19页
Side lobe level reduction(SLL)of antenna arrays significantly enhances the signal-to-interference ratio and improves the quality of service(QOS)in recent and future wireless communication systems starting from 5G up t... Side lobe level reduction(SLL)of antenna arrays significantly enhances the signal-to-interference ratio and improves the quality of service(QOS)in recent and future wireless communication systems starting from 5G up to 7G.Furthermore,it improves the array gain and directivity,increasing the detection range and angular resolution of radar systems.This study proposes two highly efficient SLL reduction techniques.These techniques are based on the hybridization between either the single convolution or the double convolution algorithms and the genetic algorithm(GA)to develop the Conv/GA andDConv/GA,respectively.The convolution process determines the element’s excitations while the GA optimizes the element spacing.For M elements linear antenna array(LAA),the convolution of the excitation coefficients vector by itself provides a new vector of excitations of length N=(2M−1).This new vector is divided into three different sets of excitations including the odd excitations,even excitations,and middle excitations of lengths M,M−1,andM,respectively.When the same element spacing as the original LAA is used,it is noticed that the odd and even excitations provide a much lower SLL than that of the LAA but with amuch wider half-power beamwidth(HPBW).While the middle excitations give the same HPBWas the original LAA with a relatively higher SLL.Tomitigate the increased HPBWof the odd and even excitations,the element spacing is optimized using the GA.Thereby,the synthesized arrays have the same HPBW as the original LAA with a two-fold reduction in the SLL.Furthermore,for extreme SLL reduction,the DConv/GA is introduced.In this technique,the same procedure of the aforementioned Conv/GA technique is performed on the resultant even and odd excitation vectors.It provides a relatively wider HPBWthan the original LAA with about quad-fold reduction in the SLL. 展开更多
关键词 Array synthesis convolution process genetic algorithm(GA) half power beamwidth(HPBW) linear antenna array(LAA) side lobe level(SLL) quality of service(qos)
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Performance Analysis of Intelligent CR-NOMA Model for Industrial IoT Communications 被引量:5
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作者 Yinghua Zhang Jian Liu +2 位作者 Yunfeng Peng Yanfang Dong Changming Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第10期239-257,共19页
Aiming for ultra-reliable low-latency wireless communications required in industrial internet of things(IIoT)applications,this paper studies a simple cognitive radio non-orthogonal multiple access(CR-NOMA)downlink sys... Aiming for ultra-reliable low-latency wireless communications required in industrial internet of things(IIoT)applications,this paper studies a simple cognitive radio non-orthogonal multiple access(CR-NOMA)downlink system.This system consists of two secondary users(SUs)dynamically interfered by the primary user(PU),and its performance is characterized by the outage probability of the SU communications.This outage probability is calculated under two conditions where,a)the transmission of PU starts after the channel state information(CSI)is acquired,so the base station(BS)is oblivious of the interference,and b)when the BS is aware of the PU interference,and the NOMA transmission is adapted to the more comprehensive knowledge of the signal to interference plus noise ratio(SINR).These results are verified by simulations,and their good agreement suggests our calculations can be used to reduce the complexity of future analysis.We find the outage probability is reduced when the SUs move further away from the primary transmitter or when the signal from PU is less powerful,and the BS always has better performance when it is aware of the interference.The findings thus emphasize the importance of monitoring the channel quality and realtime feedback to optimize the performance of CR-NOMA system. 展开更多
关键词 Industrial internet of things(IIoT) non-orthogonal multiple access(NOMA) quality of service(qos) successive interference cancellation(SIC)
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WEB SERVICE SELECTION ALGORITHM BASED ON PRINCIPAL COMPONENT ANALYSIS 被引量:4
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作者 Kang Guosheng Liu Jianxun +1 位作者 Tang Mingdong Cao Buqing 《Journal of Electronics(China)》 2013年第2期204-212,共9页
Existing Web service selection approaches usually assume that preferences of users have been provided in a quantitative form by users. However, due to the subjectivity and vagueness of preferences, it may be impractic... Existing Web service selection approaches usually assume that preferences of users have been provided in a quantitative form by users. However, due to the subjectivity and vagueness of preferences, it may be impractical for users to specify quantitative and exact preferences. Moreover, due to that Quality of Service (QoS) attributes are often interrelated, existing Web service selection approaches which employ weighted summation of QoS attribute values to compute the overall QoS of Web services may produce inaccurate results, since they do not take correlations among QoS attributes into account. To resolve these problems, a Web service selection framework considering user's preference priority is proposed, which incorporates a searching mechanism with QoS range setting to identify services satisfying the user's QoS constraints. With the identified service candidates, based on the idea of Principal Component Analysis (PCA), an algorithm of Web service selection named PCA-WSS (Web Service Selection based on PCA) is proposed, which can eliminate the correlations among QoS attributes and compute the overall QoS of Web services accurately. After computing the overall QoS for each service, the algorithm ranks the Web service candidates based on their overall QoS and recommends services with top QoS values to users. Finally, the effectiveness and feasibility of our approach are validated by experiments, i.e. the selected Web service by our approach is given high average evaluation than other ones by users and the time cost of PCA-WSS algorithm is not affected acutely by the number of service candidates. 展开更多
关键词 Principal Component Analysis (PCA) Web service selection quality of service (qos) Overall evaluation
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