Service Quality Measurement and Competition Strategy Analysis of Online Shopping

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.

基于加速无约束张量隐因子分解模型的Web服务Qo S估计

针对基于张量非负隐因子分解模型的Web服务QoS估计方法过于依赖非负初始随机数据以及特意设计的非负训练方法,导致模型的兼容性和扩展性不高的问题,提出了加速无约束张量隐因子分解模型。其主要思想包括三部分:将非负性约束从决策参数转移到输出的隐因子,并通过单元素映射函数连接它们;运用结合动量方法的随机梯度下降算法,有效提高模型的收敛速度与估计精度;给出加速无约束张量隐因子分解模型的详细算法和结果分析。在实际工业应用中的2个动态QoS数据集上的实证研究表明,与最先进的QoS估计模型相比,所提模型具有较高的计算效率和估计精度。

WEB SERVICE SELECTION ALGORITHM BASED ON PRINCIPAL COMPONENT ANALYSIS

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.

一种可扩展的Web Service QoS管理框架

Web Service是目前研究界和产业界广泛关注的技术之一.随着Web Service的广泛应用,研究者们普遍认识到,服务的非功能属性,即服务质量(Quality of Service,QoS)是面向服务的应用能否成功的关键因素之一.因此,研究者们尝试从多个角度对QoS相关问题展开了研究.然而,现有工作普遍关注基于QoS的动态服务选择和组装等上层应用技术,而对于如何获取、存储、度量QoS等基础支持技术研究较少,而这些基础性工作对QoS相关的研究工作具有显著的重要性.此外,不同应用领域对Web Service QoS的需求不尽相同,因此,需要有一套灵活的机制支持在QoS模型定义、QoS度量方法、QoS信息采集等方面体现出的领域特性.针对这个问题,文中提出了一个可扩展的Web Service QoS信息管理框架,详细分析了该框架涉及到的重要方法与核心技术,并给出了该框架在北京大学软件构件库系统中的设计决策和方案.最后,介绍了文中框架在一个863计划项目中的应用实例,该实例展示了用户根据其应用的领域需求对本框架进行扩展并进行Web Service QoS管理的方法,从而验证了本管理框架的可扩展性及实用性.

基于Web Services的数字化制造软资源支撑系统开发

通过分析档案管理系统的开发流程和需求,针对数字化制造软资源管理业务中存在的手工管理为主、设计和生产信息不流畅等管理现状,构建了基于Web Services的数字化制造软资源管理业务流程,提出了基于Web Services的数字化制造软资源支撑系统框架,并设计和实现了该系统。实验结果表明,该系统能够对图纸、文件等纸质、电子文件进行一体化管理,基于Web Services技术是构建数字化制造软资源支撑系统的有效方式。

QoS驱动的Web services动态计价机制研究

结合Web services的服务质量(QoS)因素和用户经验,对Web services的计价机制进行研究,提出一种QoS驱动的Web services动态计价模型,描述其计价过程,并给出相应的实现算法。通过对模型的简单实现,经测试这一计价模型在准确性和合理性上具有一定优势。

Web Service Description and Discovery Based on Semantic Model

A novel semantic model of Web service descrip tion and discovery was proposed through an extension for profile model of Web ontology language for services （OWL-S） in this paper. Similarity matching of Web services was implemented through computing weighted summation of semantic similarity value based on specific domain ontology and dynamical satisfy extent evaluation for quality of service （QoS）. Experiments show that the provided semantic matching model is efficient.

A Method for Service-Oriented Personalized Requirements Analysis

The development of Web service has changed the process of software production, and requirements engineering becomes the key issue of service-oriented software engineering. Meantime, it reduces the degree of difficulty of software production, which facilitates end-users to customize software according to their personalized requirements. The paper proposes a method for service-oriented personalized requirements analysis, which is based on domain goal model and process model. The method can inform users of potential errors in requirements by detecting the correctness of requirements, which is driven by users’ personalized operations on goal models, and customize personalized processes to satisfy users’ requirements by reusing domain processes. The personalized processes are the basis for Web service discovery and composition.

Location Based Services Acceptance and Adoption Evaluation: An Investigation on Mobile Phone Users’ Response to Awareness and Utilization of LBS Technology in Nairobi Kenya

Location Based Navigation System (LBNS) is a specific Location Based Service (LBS) purely for navigational purpose. These systems resolve position of a user by using GNSS/GPS positioning technologies, to which supplementary information on goods and services are tagged. The navigation services have become popular and can be installed on mobile phones to provide route information, location of points of interest and user’s current location. LBS has continued to face challenges which include “communication” process towards user reference. Location Based Service System conveys suitable information through a mobile device for effective decision making and reaction within a given time span. This research was geared at understanding the state of LBS technology acceptance and adoption by users in Nairobi Kenya. To do this a quantitative study was carried out through a questionnaire, to investigate mobile phone users’ response on awareness and use of LBS technology. Testing the growth of this technology in this region compared to predictions in previous studies using Technology Acceptance Model (TAM), it is evident that many users may be aware of GPS functionality in mobile phones but are certainly yet to fully embrace the technology as they rarely use it. This points to some underlying challenges towards this technology within this part of the World, thereby recommending for deliberate monitoring and evaluation of LBS technology for sustenance growth based on user satisfaction and acceptance for improved usability.

Temporal and spatial responses of ecological resilience to climate change and human activities in the economic belt on the northern slope of the Tianshan Mountains, China

In the Anthropocene era,human activities have become increasingly complex and diversified.The natural ecosystems need higher ecological resilience to ensure regional sustainable development due to rapid urbanization and industrialization as well as other intensified human activities,especially in arid and semi-arid areas.In the study,we chose the economic belt on the northern slope of the Tianshan Mountains(EBNSTM)in Xinjiang Uygur Autonomous Region of China as a case study.By collecting geographic data and statistical data from 2010 and 2020,we constructed an ecological resilience assessment model based on the ecosystem habitat quality(EHQ),ecosystem landscape stability(ELS),and ecosystem service value(ESV).Further,we analyzed the temporal and spatial variation characteristics of ecological resilience in the EBNSTM from 2010 to 2020 by spatial autocorrelation analysis,and explored its responses to climate change and human activities using the geographically weighted regression(GWR)model.The results showed that the ecological resilience of the EBNSTM was at a low level and increased from 0.2732 to 0.2773 during 2010–2020.The spatial autocorrelation analysis of ecological resilience exhibited a spatial heterogeneity characteristic of"high in the western region and low in the eastern region",and the spatial clustering trend was enhanced during the study period.Desert,Gobi and rapidly urbanized areas showed low level of ecological resilience,and oasis and mountain areas exhibited high level of ecological resilience.Climate factors had an important impact on ecological resilience.Specifically,average annual temperature and annual precipitation were the key climate factors that improved ecological resilience,while average annual evapotranspiration was the main factor that blocked ecological resilience.Among the human activity factors,the distance from the main road showed a negative correlation with ecological resilience.Both night light index and PM2.5 concentration were negatively correlated with ecological resilience in the areas with better ecological conditions,whereas in the areas with poorer ecological conditions,the correlations were positive.The research findings could provide a scientific reference for protecting the ecological environment and promoting the harmony and stability of the human-land relationship in arid and semi-arid areas.

Quantitative Analysis法在木兰溪水质模型选择中的应用

木兰溪是闽中最大的溪流,为福建省八条主要水系之一.对木兰溪水质模型进行选择可以根据Quantitative Analysis法,由Pe(Peclet Number)的范围来判断污染物在河流三维上的混合情况.通过将木兰溪划分为四个计算(控制)单元,对控制单元4的Pe值进行计算,快速准确地确定了适合木兰溪的简单实用的水质数学模型.

以新浪微博为例的社交网络服务质量改进

随着社交网络的不断发展与流行,社交网络的服务质量以及经营成效成为了运营商赢得市场竞争优势的关键,研究社交网络服务质量改进有利于提升运营商的市场竞争力。在理论与现有文献研究基础上开发了社交网络服务质量量表,以中国的社交网络新浪微博为例,基于开发的量表结合KANO模型及IPA分析方法探讨新浪微博网络服务质量的特性以及服务质量提升建议,并根据企业当前的绩效和融入战略之后的改进策略进行对比分析。实证分析表明,新浪微博网络服务质量具有二维质量的属性,而且考虑企业战略有助于管理者做出更完善的质量改善决策。

混合性焦虑抑郁障碍服务质量情感主题识别研究

[目的/意义]为识别在线医疗社区中混合性焦虑抑郁障碍患者评论医疗服务质量情感及主题,提出一种基于CNN-BiLSTM和LDA模型的服务质量情感主题识别模型。[方法/过程]首先,构建CNN-BiLSTM模型提取患者评论内外关键特征得到情感倾向分布;其次,运用LDA主题模型提取患者正负向评论主题,结合《医院评价标准(征求意见稿)》得到医疗服务质量主题,从分布和情感词对正负向服务质量进行挖掘。[结果/结论]CNN-BiLSTM的F1值为94.43%,均优于其他对比模型;结合LDA主题模型和相关文献得到5维医疗服务质量主题及分布;根据主题情感词及分布得到负向评论产生的主要原因,为识别和改善医疗服务质量提供有效决策支持。

基于时间概率代价进程代数的Web服务组合建模和分析

形式化建模Web服务组合并分析其功能正确性和QoS可满足性,是提高组合服务可信性的重要手段,但目前形式化方法侧重功能正确性建模和分析,对QoS可满足性的建模和分析支持不足.为此提出一种时间概率代价进程代数TPPPA(Timed Probabilistic Priced Process Algebra),给出了TPPPA的语法和语义,并证明其具有功能、时间、概率和代价的统一建模和分析能力.用实例表明了TPPPA可有效支持Web服务组合功能正确性和QoS可满足性的形式化统一建模和分析.

一种支持QoS约束的Web服务发现模型

服务质量(QoS)描述了一个产品或服务满足消费者需求的能力.提供有保证的 QoS是 Web服务在商业应用中获得成功的关键.如何动态地选择出最适合用户需求的Web服务正在引起研究领域的关注.该文提出了一种支持QoS约束的Web服务发现模型(WSDM- Q).该模型定义了一组描述Web服务QoS及信誉度的分类tModel,引入了QoS量化的概念,采用了QoS协商和反馈机制,支持携带 QoS描述信息的服务发布和基于 QoS约束的服务发现.协商机制允许服务提供者根据运行时的状态对服务请求进行接纳控制,反馈机制允许服务注册中心对服务提供QoS的信誉度进行动态评估和调整.该模型不需要改变 UDDI的内部实现,能够直接在现有的 UDDI服务上进行扩展.作者已经基于Microsoft.Netf平台和Microsoft UDDI服务实现了一个原型系统.

基于工作流的Web服务组合多视图模型

基于工作流建模技术,提出一种包含个性化服务质量需求且具有多视图特性的服务组合模型,包括过程模型、资源模型、需求模型和服务组合相关数据。过程模型建立在活动网络图基础上,扩展了其表述能力,具有较好的可读性;资源模型考虑服务的功能和非功能特性,有很好的扩展性;需求模型采用定性和定量描述相结合的方式,来体现个性化的全局服务质量需求。基于该模型给出了一个服务组合建模的原型系统,初步验证了模型的可用性。

基于二维QoS模型的Web服务组合

在实际应用中,单个Web服务通常无法满足复杂应用的需求,如何组合已有的服务,从而提供更强大更完整的商业功能已成为此领域的研究热点。然而现行的SOA架构中,Web服务组合方法中很少考虑Web服务质量(QoS)问题,或者对QoS考虑得不够全面,这样,组合出的服务不能确保能够满足用户的QoS需求。针对这一问题,提出了Web服务的二维QoS模型,并使用了改进的UDDI规范,在此基础上给出了基于QoS的Web服务组合的有色Petri网组合策略。在满足用户组合服务的功能需求的同时,也满足了用户对服务质量QoS的需求,实现了需求服务的优化。

基于InVEST模型的武夷山市生境质量时空分析

为了探求快速城市化背景下城市生境质量对生态协调发展的影响,基于InVEST模型对武夷山地区生境质量时空演变进行分析。结果表明,2010-2020年,生境质量为高级的地区由95.43%下降到88.92%,中等生境质量所占的面积由3.67%升到9.54%,生境退化区域具有显著的空间聚集性特点。武夷山生境质量总体保持相对较好,映射出近年来生态保护措施的成效较好。研究结果对于武夷山地区在权衡发展和保护之间寻求最优自然资源管理和经济发展模式提供理论决策依据。

考虑QoS属性相关性的Web服务选择

现有的Web服务选择方法通常假定偏好由用户给出.由于偏好的主观性和模糊性,用户通常无法用具体数字表达清楚自己的偏好.且QoS各维属性之间存在相关性,偏好加权的方法无法消除信息的重叠,导致服务综合QoS评价不准确.针对该问题,在Web服务选择框架中对QoS属性设置区间搜索以考虑用户的优先偏好,使得初选的服务满足用户的QoS约束.对初选的服务利用主成分分析的思想,提出一种可行的Web服务选择算法PCA-WSS,根据各主成分的贡献率进行加权,分离QoS各维属性之间存在的相关性,有效地评价服务的综合QoS,为用户选择综合QoS最优的服务.实验结果验证算法的有效性和可行性.