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Spatiotemporal variations in ecosystem services and their trade-offs and synergies against the background of the gully control and land consolidation project on the Loess Plateau,China
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作者 WANG Jing WEI Yulu +2 位作者 PENG Biao LIU Siqi LI Jianfeng 《Journal of Arid Land》 SCIE CSCD 2024年第1期131-145,共15页
Studying the spatiotemporal variations in ecosystem services and their interrelationships on the Loess Plateau against the background of the gully control and land consolidation(GCLC)project has significant implicatio... Studying the spatiotemporal variations in ecosystem services and their interrelationships on the Loess Plateau against the background of the gully control and land consolidation(GCLC)project has significant implications for ecological protection and quality development of the Yellow River Basin.Therefore,in this study,we took Yan'an City,Shaanxi Province of China,as the study area,selected four typical ecosystem services,including soil conservation service,water yield service,carbon storage service,and habitat quality service,and quantitatively evaluated the spatiotemporal variation characteristics and trade-offs and synergies of ecosystem services from 2010 to 2018 using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.We also analysed the relationship between the GCLC project and regional ecosystem service changes in various regions(including 1 city,2 districts,and 10 counties)of Yan'an City and proposed a coordinated development strategy between the GCLC project and the ecological environment.The results showed that,from 2010 to 2018,soil conservation service decreased by 7.76%,while the other three ecosystem services changed relatively little,with water yield service increasing by 0.56% and carbon storage service and habitat quality service decreasing by 0.16% and 0.14%,respectively.The ecological environment of Yan'an City developed in a balanced way between 2010 and 2018,and the four ecosystem services showed synergistic relationships,among which the synergistic relationships between soil conservation service and water yield service and between carbon storage service and habitat quality service were significant.The GCLC project had a negative impact on the ecosystem services of Yan'an City,and the impact on carbon storage service was more significant.This study provides a theoretical basis for the scientific evaluation of the ecological benefits of the GCLC project and the realization of a win-win situation between food security and ecological security. 展开更多
关键词 ecosystem services trade-offs and synergies gully control and land consolidation habitat quality Integrated Valuation of Ecosystem services and Trade-offs(InVEST)model Loess Plateau
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Influence of Human Activity Intensity on Habitat Quality in Hainan Tropical Rainforest National Park,China
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作者 HAN Nianlong YU Miao +2 位作者 JIA Peihong ZHANG Yucheng HU Ke 《Chinese Geographical Science》 SCIE CSCD 2024年第3期519-532,共14页
Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding s... Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding scope and intensity of human activity impact,the regional ecological security is facing serious challenges.A scientific assessment of the interrelationship between human activity intensity and habitat quality in the HTRNP is a prerequisite for achieving effective management of ecological disturbances caused by human activities and can also provide scientific strategies for the sustainable development of the region.Based on the land use change data in 2000,2010,and 2020,the spatial and temporal variations and the relationship between habitat quality(HQ)and human activity intensity(HAI)in the HTRNP were explored using the integrated valuation of ecosystem services and trade-offs(InVEST)model.System dynamics and land use simulation models were also combined to conduct multi-scenario simulations of their relationships.The results showed that during 2000–2020,the habitat quality of the HTRNP improved,the intensity of human activities decreased each year,and there was a negative correlation between the two.Second,the system dynamic model could be well coupled with the land use simulation model by combining socio-economic and natural factors.The simulation scenarios of the coupling model showed that the harmonious development(HD)scenario is effective in curbing the increasing trend of human activity intensity and decreasing trend of habitat quality,with a weaker trade-off between the two compared with the baseline development(BD)and investment priority oriented(IPO)scenarios.To maintain the authenticity and integrity of the HTRNP,effective measures such as ecological corridor construction,ecological restoration,and the implementation of ecological compensation policies need to be strengthened. 展开更多
关键词 human activity intensity(HAI) habitat quality(HQ) bivariate spatial autocorrelation system dynamics model integrated valuation of ecosystem services and trade-offs(InVEST)model Hainan Tropical Rainforest National Park(HTRNP)of China
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Spatiotemporal variations of ecosystem services and driving factors in the Tianchi Bogda Peak Natural Reserve of Xinjiang,China
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作者 ZHU Haiqiang WANG Jinlong +2 位作者 TANG Junhu DING Zhaolong GONG Lu 《Journal of Arid Land》 SCIE CSCD 2024年第6期816-833,共18页
Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,i... Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,is an important ecological barrier area in the temperate arid zone.The evaluation of its important ecosystem services is of great significance to improve the management level and ecological protection efficiency of the reserve.In the present study,we assessed the spatiotemporal variations of four ecosystem services(including net primary productivity(NPP),water yield,soil conservation,and habitat quality)in the TBPNR from 2000 to 2020 based on the environmental and social data using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.In addition,the coldspot and hotspot areas of ecosystem services were identified by hotspot analysis,and the trade-off and synergistic relationships between ecosystem services were analyzed using factor analysis in a geographic detector.During the study period,NPP and soil conservation values in the reserve increased by 48.20%and 25.56%,respectively;conversely,water yield decreased by 16.56%,and there was no significant change in habitat quality.Spatially,both NPP and habitat quality values were higher in the northern part and lower in the southern part,whereas water yield showed an opposite trend.Correlation analysis revealed that NPP showed a synergistic relationship with habitat quality and soil conservation,and exhibited a trade-off relationship with water yield.Water yield and habitat quality also had a trade-off relationship.NPP and habitat quality were affected by annual average temperature and Normalized Difference Vegetation Index(NDVI),respectively,while water yield and soil conservation were more affected by digital elevation model(DEM).Therefore,attention should be paid to the spatial distribution and dynamics of trade-off and synergistic relationships between ecosystem services in future ecological management.The findings of the present study provide a reference that could facilitate the sustainable utilization of ecosystem services in the typical fragile areas of Northwest China. 展开更多
关键词 net primary productivity(NPP) water yield soil conservation habitat quality Integrated Valuation of Ecosystem services and Trade-offs(InVEST)model geographic detector Tianchi Bogda Peak Natural Reserve
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SERVQUAL Model Based Evaluation Analysis of Railway Passenger Transport Service Quality in China 被引量:1
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作者 Huiwei Niu Jiao Yao +1 位作者 Jing Zhao Jin Wang 《Journal on Big Data》 2019年第1期17-24,共8页
Railway is the backbone of Chinese transportation system,but its poor quality of services for passengers cause complains now and then.This study first analyzed the influencing factors of service quality on railway pas... Railway is the backbone of Chinese transportation system,but its poor quality of services for passengers cause complains now and then.This study first analyzed the influencing factors of service quality on railway passenger,and its quality characteristics was also explained,and finally we proposed an evaluation system of service quality on railway passenger transport.Through the statistical analysis and processing of the basic information from survey data from railway station,trains and the official website of the ticket purchase,the evaluation score of question naire was converted into the score in evaluation index system,which was based on SERVQUAL model.Finally,the evaluation index system was applied to the field test,and all levels of indicators and the overall evaluation of railway passenger transport service quality was obtained.The relevant results show that the evaluation model of this study is concise and practical,and the method has certain practicability and promotion value,which is beneficial to the department of management supervision in railway transportation. 展开更多
关键词 RAILWAY PASSENGER TRANSPORT service quality evaluation INDEX SERVQUAL model PASSENGER SATISFACTION
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A multidimensional and hierarchical model of library mobile service quality 被引量:5
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作者 Yang ZHAO Guo CHEN 《Chinese Journal of Library and Information Science》 2013年第3期59-74,共16页
Purpose:Based on the understanding of the characteristics of mobile services(m-services)provided by libraries,we attempt to develop a multidimensional and hierarchical model and a specifically designed measurement sca... Purpose:Based on the understanding of the characteristics of mobile services(m-services)provided by libraries,we attempt to develop a multidimensional and hierarchical model and a specifically designed measurement scale for the assessment of libraries' m-service quality.Design/methodology/approach:The research has been conducted sequentially in two stages.At the first stage,a multidimensional and hierarchical model of library m-service quality and a measurement scale are developed through literature review and focus group interviews.At the second stage the model is tested using partial disaggregation technique for an analysis of the data collected from over 400 library users in 3 Chinese universities.Findings:The proposed model is shown to fit the data well.The empirical analysis provides strong support for the model,which includes 4 dimensions(service environment,service interaction,information control and service effect) and 12 corresponding sub-dimensions.Research limitations:The sample size needs to be enlarged and the user types need to be expanded to make the sample more representative.Practical implications:The study provides a conceptual framework and measurement tool that can help library managers understand the users' needs in the context of mobile network environment,and boost their libraries' competitiveness by carrying out better services to meet the user demands.Originality/value:The proposed model and measurement scale specifically designed for the assessment of libraries' m-service quality fully reflect the hierarchical structure of libraries' m-service quality.In addition,by using partial disaggregation technique for model testing,we believe our research can serve as a practical reference to those engaged in the development and examination of a multidimensional and hierarchical model. 展开更多
关键词 Library mobile service(m-service) Mobile service quality Multidimensional and hierarchical method service quality evaluation model
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Application of Structural Equation Modeling to Evaluate Service Quality of Sportswear Retailing 被引量:1
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作者 李敏 顾彤宇 +1 位作者 杨以雄 洪涛敏 《Journal of Donghua University(English Edition)》 EI CAS 2008年第1期6-10,共5页
Structural Equation Modeling(SEM) used widely in sociology,economics and psychology is adopted.Based on data obtained from marketing research,and using statistical analysis software SPSS11.0 and LISREL8.7,Theory of Fi... Structural Equation Modeling(SEM) used widely in sociology,economics and psychology is adopted.Based on data obtained from marketing research,and using statistical analysis software SPSS11.0 and LISREL8.7,Theory of Five Dimensions of service quality is proved to be suitable in sportswear retailing in China.It analyzes the relationship among five dimensions and puts them in order of importance as to service quality in sportswear retailing.Advices are given for sportswear retail companies to improve their service quality and enhance customer loyalty. 展开更多
关键词 运动装 服装行业 服务质量 评价方法
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Exploration on the Construction of Mobile Library Service Quality Optimization Model
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作者 Huimin Zheng 《Journal of Contemporary Educational Research》 2019年第6期39-42,共4页
The emergence of science and technology and big data has promoted the emergence of major resource platforms.Mobile libraries have emerged as the world progresses.Users have put forward high requirements for service qu... The emergence of science and technology and big data has promoted the emergence of major resource platforms.Mobile libraries have emerged as the world progresses.Users have put forward high requirements for service quality in the process of using mobile libraries.Optimizing service quality is one of the important topics of mobile libraries today.In our paper the mobile library service quality optimization model is constructed from three aspects,including the starting point of the optimization model,the optimization content,and the final construction.While keeping up with the pace of the times,we will meet the needs of users and enhance user satisfaction in order to promote the development and advancement of mobile libraries. 展开更多
关键词 MOBILE LIBRARY service quality service model
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Application of Structural Equation Model to Evaluate the Perception of Service Quality of Medical Staffs of infectious Disease Department in Chinese Hospitals
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作者 Min Li Ren-tian Cai Cheng-yu Huang 《国际感染病学(电子版)》 CAS 2014年第4期179-186,共8页
Objective To enhance the quality of medical service for Chinese patients through research of service quality from Chinese medical personnel. Methods Serv Qual scale was used for infection medical staffs randomly by sa... Objective To enhance the quality of medical service for Chinese patients through research of service quality from Chinese medical personnel. Methods Serv Qual scale was used for infection medical staffs randomly by sampling questionnaire in Beijing, Shanghai, Chengdu, Chongqing, Guangzhou and Nanning. The data collected were entered and analyzed using SPSS 20.0. Statistical methods included frequency, factor analysis, reliability analysis, correlation analysis, independent samples t test, one-way analyses of variance, simultaneous regression analysis and structural equation model analysis. Results The Kaiser-Meyer-Olkin value for the factor analysis of the scale was 0.970. The Cronbach's α for the reliability analysis was 0.975. The Pearson correlation coefficients were 0.624-0.874 and statistically significant. Undergraduates felt good, Ph D students felt bad; the doctors felt bad; managers felt good. Standard 5 dimensions of the regression coefficients were positive, including empathy(β = 0.288), reliability(β = 0.241) impacting on perceived service quality mostly. The control ability and stability of the standard error of perceived service quality directly effected value were 0.646 and 0.382, respectively. Conclusions Medical staffs of infectious disease department have poor perception of service quality. Hospitals should improve awareness and of clinicians and deepen the reform of the medical care system. 展开更多
关键词 Structural equation models Infectious disease department Perception of service quality
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基于SDN的卫星网络端到端QoS类映射研究
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作者 魏德宾 李婧 潘成胜 《计算机仿真》 2024年第7期55-60,共6页
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... 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。 展开更多
关键词 卫星网络 软件定义网络 服务质量 服务质量映射
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Toward Cloud Computing QoS Architecture:Analysis of Cloud Systems and Cloud Services 被引量:20
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作者 Mohammad Hossein Ghahramani MengChu Zhou Chi Tin Hon 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2017年第1期6-18,共13页
Cloud can be defined as a new computing paradigm that provides scalable, on-demand, and virtualized resources for users. In this style of computing, users can access a shared pool of computing resources which are prov... Cloud can be defined as a new computing paradigm that provides scalable, on-demand, and virtualized resources for users. In this style of computing, users can access a shared pool of computing resources which are provisioned with minimal management efforts of users. Yet there are some obstacles and concerns about the use of clouds. Guaranteeing quality of service(Qo S) by service providers can be regarded as one of the main concerns for companies tending to use it. Service provisioning in clouds is based on service level agreements representing a contract negotiated between users and providers. According to this contract, if a provider cannot satisfy its agreed application requirements, it should pay penalties as compensation. In this paper, we intend to carry out a comprehensive survey on the models proposed in literature with respect to the implementation principles to address the QoS guarantee issue. 展开更多
关键词 Cloud computing quality of service(qos) service level agreements(SLA) system-of-systems(SoS)
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ILSM:Incorporated Lightweight Security Model for Improving QOS in WSN
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作者 Ansar Munir Shah Mohammed Aljubayri +4 位作者 Muhammad Faheem Khan Jarallah Alqahtani Mahmood ul Hassan Adel Sulaiman Asadullah Shaikh 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期2471-2488,共18页
In the network field,Wireless Sensor Networks(WSN)contain prolonged attention due to afresh augmentations.Industries like health care,traffic,defense,and many more systems espoused the WSN.These networks contain tiny ... In the network field,Wireless Sensor Networks(WSN)contain prolonged attention due to afresh augmentations.Industries like health care,traffic,defense,and many more systems espoused the WSN.These networks contain tiny sensor nodes containing embedded processors,TinyOS,memory,and power source.Sensor nodes are responsible for forwarding the data packets.To manage all these components,there is a need to select appropriate parameters which control the quality of service of WSN.Multiple sensor nodes are involved in transmitting vital information,and there is a need for secure and efficient routing to reach the quality of service.But due to the high cost of the network,WSN components have limited resources to manage the network.There is a need to design a lightweight solution that ensures the quality of service in WSN.In this given manner,this study provides the quality of services in a wireless sensor network with a security mechanism.An incorporated hybrid lightweight security model is designed in which random waypoint mobility(RWM)model and grey wolf optimization(GWO)is used to enhance service quality and maintain security with efficient routing.MATLAB version 16 andNetwork Stimulator 2.35(NS2.35)are used in this research to evaluate the results.The overall cost factor is reduced at 60%without the optimization technique and 90.90%reduced by using the optimization technique,which is assessed by calculating the signal-to-noise ratio,overall energy nodes,and communication overhead. 展开更多
关键词 Wireless sensor networks quality of service random waypoint mobility model grey wolf optimization security
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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 qos模型 WEB服务器 模糊综合评价 运行时间监控
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A Fuzzy Directed Graph-Based QoS Model for Service Composition
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作者 GUO Sanjun DOU Wanchun FAN Shaokun 《Wuhan University Journal of Natural Sciences》 CAS 2007年第5期861-865,共5页
Web service composition lets developers create applications on top of service-oriented computing and its native description, discovery, and communication capabilities. This paper mainly focuses on the QoS when the con... Web service composition lets developers create applications on top of service-oriented computing and its native description, discovery, and communication capabilities. This paper mainly focuses on the QoS when the concrete composition structure is unknown. A QoS model of service composition is presented based on the fuzzy directed graph theory. According to the model, a recursive algorithm is also described for calculating such kind of QoS. And, the feasibility of this QoS model and the recursive algorithm is verified by a case study. The proposed approach enables customers to get a possible value of the QoS before they achieve the service. 展开更多
关键词 fuzzy directed graph service composition qos model Web service
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Modeling and analysis of multiservice queuing system for WiMAX network
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作者 SADIA Murawwat AKHTAR Hussain +3 位作者 MUHAMMAD Imran 赵三元 刘振娟 牛慧博 《Journal of Beijing Institute of Technology》 EI CAS 2013年第1期43-48,共6页
An analytical queuing model is proposed for the classified services of WiMAX network. Simulation model is also developed that corresponds to the Markovian analytical model using Java modeling tool (JMT). This is a n... An analytical queuing model is proposed for the classified services of WiMAX network. Simulation model is also developed that corresponds to the Markovian analytical model using Java modeling tool (JMT). This is a new and efficient discrete event tool for queuing network modeling and workload analysis. QoS metrics have been evaluated for the multi-rate traffic in multiple scenari- os. Results obtained from simulation are compared for validation and analysis. Outcomes show that the proposed model is more efficient than the conventional method by improving residence time, re- sponse time, increasing system throughput and efficiency at queuing level with a slight degradation in call acceptance factor. 展开更多
关键词 multi-rate traffic Markov Poisson process queuing model quality of service WIMAX
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A synthesizing control model of networked control systems to guarantee QoP and QoS
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作者 Jun KANG Guanzhong DAI 《控制理论与应用(英文版)》 EI 2008年第4期379-384,共6页
The whole performance of the networked control system (NCSs) depends on two interaction factors, namely the quality of control performance (QoP) and quality of network service (QoS). So, to optimize the whole pe... The whole performance of the networked control system (NCSs) depends on two interaction factors, namely the quality of control performance (QoP) and quality of network service (QoS). So, to optimize the whole perfor-mance of NCSs, the problem of guaranteeing QoP and QoS plays an important role in the design of NCSs. However, up to now, little work has been done in this field. In this paper, a synthesizing control model of NCSs to guarantee QoP and QoS is proposed, and a feasible condition of optimizing whole performance of NCSs is also suggested. Finally, the simulation results show that the proposed model is effective. 展开更多
关键词 Networked control system (NCSs) Synthesizing control quality of control performance (QoP) quality of network service qos
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How do Users Evaluate Service Quality of the Dockless Bicycle Sharing System?
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作者 Jianrong Liu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2020年第1期19-35,共17页
In order to improve the public transit’s accessibility and promote service quality of the public transit,it is necessary to alleviate the“last⁃mile”problem.The combination of the public transit and bicycle⁃sharing ... In order to improve the public transit’s accessibility and promote service quality of the public transit,it is necessary to alleviate the“last⁃mile”problem.The combination of the public transit and bicycle⁃sharing system is competitive compared with the private car.In 2016,the dockless bicycle⁃sharing system has been undergoing tremendous development.Because the dockless bicycle⁃sharing system is different from previous bicycle⁃sharing systems,components of service quality of the dockless bicycle⁃sharing system differ.However,there are few articles about the service quality of the dockless bicycle⁃sharing system.This paper examined the evaluation of service quality of the dockless bicycle⁃sharing system along with a measurement of users’satisfaction.A questionnaire about service quality was designed,which includes 15 factors.Through the analysis of travelers’evaluation of factors of the dockless bicycle⁃sharing system with Rasch Model,these original ordinal data(Likert data)was transformed to the interval data:the person parameter(ability)and the item parameter(difficulty).Through the analysis of interviewees’abilities,it was found that only education and monthly consumption have significant influence on interviewees’evaluation of service quality of the dockless bicycle⁃sharing system,while there is no significant influence of gender,weekly use of dockless shared⁃bicycle,private car ownership,or monthly income on the evaluation.Furthermore,it was found that users were dissatisfied with cycling under the adverse weather,disturbance from pedestrians and cars,continuity of the bicycle lane,complaint channel,and staff service the most. 展开更多
关键词 dockless bicycle sharing system service quality Rasch model demographic characteristic evaluation of travelers
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Hybrid Metaheuristics Web Service Composition Model for QoS Aware Services
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作者 P.Rajeswari K.Jayashree 《Computer Systems Science & Engineering》 SCIE EI 2022年第5期511-524,共14页
Recent advancements in cloud computing(CC)technologies signified that several distinct web services are presently developed and exist at the cloud data centre.Currently,web service composition gains maximum attention ... Recent advancements in cloud computing(CC)technologies signified that several distinct web services are presently developed and exist at the cloud data centre.Currently,web service composition gains maximum attention among researchers due to its significance in real-time applications.Quality of Service(QoS)aware service composition concerned regarding the election of candidate services with the maximization of the whole QoS.But these models have failed to handle the uncertainties of QoS.The resulting QoS of composite service identified by the clients become unstable and subject to risks of failing composition by end-users.On the other hand,trip planning is an essential technique in supporting digital map services.It aims to determine a set of location based services(LBS)which cover all client intended activities quantified in the query.But the available web service composition solutions do not consider the complicated spatio-temporal features.For resolving this issue,this study develops a new hybridization of the firefly optimization algorithm with fuzzy logic based web service composition model(F3L-WSCM)in a cloud environment for location awareness.The presented F3L-WSCM model involves a discovery module which enables the client to provide a query related to trip planning such as flight booking,hotels,car rentals,etc.At the next stage,the firefly algorithm is applied to generate composition plans to minimize the number of composition plans.Followed by,the fuzzy subtractive clustering(FSC)will select the best composition plan from the available composite plans.Besides,the presented F3L-WSCM model involves four input QoS parameters namely service cost,service availability,service response time,and user rating.An extensive experimental analysis takes place on CloudSim tool and exhibit the superior performance of the presented F3L-WSCM model in terms of accuracy,execution time,and efficiency. 展开更多
关键词 Web service composition trip planning hybrid models firefly algorithm qos aware services fuzzy logic
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Scheduling Algorithm with Quality of Service Support in IEEE 802.16 Networks 被引量:1
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作者 Zhang Yumei Sheng Yu 《信息通信技术》 2009年第4期44-49,共6页
The MAC layer in IEEE802.16 is designed to differentiate service among traffic categories with different multimedia requirements.In this paper,a scheduling algorithm at MAC layer for multiple connections with diverse ... The MAC layer in IEEE802.16 is designed to differentiate service among traffic categories with different multimedia requirements.In this paper,a scheduling algorithm at MAC layer for multiple connections with diverse QoS requirements is proposed.As for this algorithm,each connection is assigned a priority,which is updated dynamically based on its service status concluding queue characteristic and channel state.A connection with the highest priority is scheduled each time.Analytical model is developed by assuming a Finite State Markov Chain(FSMC)channel model.Simulation results show that the proposed scheduling algorithm can improve the performance of mean waiting time and throughput in broadband wireless networks. 展开更多
关键词 多媒体 通信 运算法则 MAC
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悬停波动对毫米波无人机通信系统QoS的影响研究
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作者 马存燕 李小亚 贺晨 《科技创新与应用》 2024年第12期96-99,共4页
毫米波无人机通信是未来通信中一种很有前途的候选者。然而,悬停无人机的随机波动会影响该通信系统的服务质量,并给毫米波无人机通信的应用带来挑战。该文从无人机位置波动对无人机-用户链路质量的影响的角度出发,研究无人机位置波动对... 毫米波无人机通信是未来通信中一种很有前途的候选者。然而,悬停无人机的随机波动会影响该通信系统的服务质量,并给毫米波无人机通信的应用带来挑战。该文从无人机位置波动对无人机-用户链路质量的影响的角度出发,研究无人机位置波动对空对地毫米波无人机通信系统QoS的影响。以可靠服务概率及覆盖概率作为评估系统QoS的指标,基于随机几何获得QoS评估指标的表达式并通过蒙特卡洛仿真进行验证。结果显示,QoS随无人机波动强度的增加而降低且存在使QoS最大的最优无人机高度,为毫米波无人机通信网的设计与研究提供参考依据。 展开更多
关键词 毫米波无人机通信 无人机位置波动 系统服务质量 随机几何 蒙特卡洛仿真
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Service Quality Measurement and Competition Strategy Analysis of Online Shopping
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作者 Chia-Huei Wu 《Macro Management & Public Policies》 2020年第1期28-32,共5页
E-Commerce refers to such business behavior as conducting trades on a virtual network through the Internet.The core elements contributing to the success of online stores include not only the web-based presentation and... E-Commerce refers to such business behavior as conducting trades on a virtual network through the Internet.The core elements contributing to the success of online stores include not only the web-based presentation and the low-price strategy but the quality of online service as well.Importance-Performance Analysis is a method frequently used to evaluate performance and analyze competition strategies.Using IPA,this study analyzed and investigated the service quality of the online shopping of a case company and proposed 10 indexes to measure the service quality of online shopping.a number of suggestions on competition strategies were provided for the case company to improve its competition strategies. 展开更多
关键词 Online shopping Importance-Performance Analysis model service quality Competition strategy
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