Dynamic Web services discovery based on similarity computation

A new approach for dynamic Web services discovery based on similarity computation in the treatment of massive Web information resource is put forward. Firstly, three kinds of service description information, textual, semantic and structural information, were modeled to compute the similarity of services. Then a novel dynamic Web services discovery mechanism was provided and the experiment on it was carried out. Results show that the new approach achieves considerable performance on precision and efficiency metrics for dynamic Web services discovery.

Towards structural web services discovery

A syntactic and structural matching mechanism for service discovery was put forward, which tries to exploit the underlying semantics of web services to enhance tbe traditional syntactic service discovery. We commit WSDL （Web Service Description Language） as service description language. The syntactic matching mechanism is based on the textual similarity among WSDL documents using VSM （ Vector Space Model）. The structural information is extracted from WSDL document tree or the invocation sequence of a series of services which can be viewed as the problem of graph isomorphism. Then we combine the syntactic and structural similarity linearly to calculate the service similarity. Finally we provide a novel web services discovery framework named SG^＊ to find the exact services meeting the users＇ goals based on service similarity.

Dynamic Service Discovery, Composition and Reconfiguration in a Model Mapping Business Process to Web Services

In any organization where SOA has been implemented, all of the web services are registered in UDDI and users’ needs are served by using appropriate web services. So in this paper, we will try to discover a service from repository first that can provide the required output to the user. The process becomes difficult when a single service is not able to fulfill a user’s need and we need a combination of services to answer complex needs of users. In our paper, we will suggest a simpler approach for dynamic service composition using a graph based methodology. This will be a design time service composition. This approach uses the functional and non-functional parameters of the services to select the most suitable services for composition as per user’s need. This approach involves “service classification” on the basis of functional parameters, “service discovery” on the basis of user’s need and then “service composition” using the selected services on the basis of non-functional parameters like response time, cost, security and availability. Another challenge in SOA implementation is that, once the composition has performed, some services may become faulty at runtime and may stop the entire process of serving a user’s need. So, we will also describe a way of “dynamic service reconfiguration” in our approach that will enable us to identify and replace a faulty service that is violating the SLA or is not accessible anymore. This service reconfiguration is done without redoing or reconfiguring the entire composition. In the end, to simulate the proposed approach, we will represent a prototype application built on php 5.4 using My SQL database at backend.

A QoS-aware Method for Web Services Discovery

The non-functional QoS (quality of service) information helps us to select a proper Web-service from the web applications, by using component services such as UDDI[1](Universal Description, Discovery, and Integration) and MDS(Monitoring and Discovery System). MDS is a suite of web services to monitor and discover resources and service on Grids, but MDS only based on function aspects. This paper studies on an approach to provide the QoS information and a discovery model by using MDS and gives a system deployment and implementation plan. The simulation results show that the method is effective in service discovery.

Development of a Smart Technique for Mobile Web Services Discovery

Web service(WS)presents a good solution to the interoperability of different types of systems that aims to reduce the overhead of high processing in a resource-limited environment.With the increasing demand for mobile WS(MWS),the WS discovery process has become a significant challenging point in the WS lifecycle that aims to identify the relevant MWSs that best match the service requests.This discovery process is a resource-consuming task that cannot be performed efficiently in a mobile computing environment due to the limitations of mobile devices.Meanwhile,a cloud computing can provide rich computing resources for mobile environments given its unlimited and easily scalable resources.This paper proposes a semantic WS discovery and invocation framework in mobile environments based on cloud and a relationship-aware matchmaking algorithm.The discovery algorithm enriches MWS and user requests semantically with the functional and non-functional properties of Ontology Web Language for Services,such as Quality of Web Service,device context,and user preferences.The WS repository is filtered based on logical reasoning and a parameter-based matching algorithm to minimize the matching space and improve runtime performance.The cosine similarity between the user request and services repository is then assessed to generate the most relevant WS.The relationships among concepts in the ontology are considered to improve the recall and precision ratio.After the WS discovery process,users can invoke and test these services in a mobile environment through a dynamic user interface.The interface of the invocation process is changed according to the WS description document.An application prototype is also developed to evaluate the framework based on a Cordova cross-mobile development framework.

Typed formal model for WS-CDL specification of web services composition

In order to formally reason and verify web services composition described by web services choreography specification WS-CDL,a typed formal model named typed Abstract WS-CDL（web services choreography description language）for WS-CDL specifications is proposed.In typed Abstract WS-CDL,the syntax of type and session,typing rules and operational semantics are formalized;the collaborations of web services are formally described by sessions;the operational semantics of a session can help to formally reason the execution of the choreography;the typing rules can help to formally check the data type consistency of exchanged information between web services and capture run-time errors due to type mismatches.Particularly,the concepts of type assumption set extension and type assumption set compatibility are proposed,and the merging algorithm of type assumption sets is defined so as to eliminate type assumption conflict.Based on the formal model,typed mapping rules for mapping web services choreography to orchestration is also defined.With the typed mapping rules,orchestration stubs and their type assumption sets can be generated from a given choreography; thus, web services composition can be verified at choreography and orchestration levels,respectively.The model is proved to have properties of type safety,and how the model can help to reason and verify web services composition is illustrated through a case study.

Web services composition with QoS bound based on simulated annealing algorithm

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.

Web services selection based on semantic similarity

Services discovery based on syntactic matching cannot adapt to the open and dynamic environment of the web. To select the proper one from the web services candidate set provided by syntactic matching, a service selection method based on semantic similarity is proposed. First, this method defines a web services ontology including QoS and context as semantic supporting, which also provides a set of terms to describe the interfaces of web services. Secondly, the similarity degree of two web services is evaluated by computing the semantic distances of those terms used to describe interfaces. Compared with existing methods, interfaces of web services can be interpreted under ontology, because it provides a formal and semantic specification of conceptualization. Meanwhile, efficiency and accuracy of services selection are improved.

A Service Design Oriented Web Services Composite Platform

In order to realize flexible, adaptable, extensible, efficient, and user-friendly service composition, we propose a service design oriented Web Service composite platform （SDOWSCP） and a service composition mechanism called composed-service-requestor-orient ed service composition （OBSDOSC）. SDOWSCP imports ontology into UDDI to define and annotate services in a flexible and intuitive manner and employs a concept of bond as a solution to the process heterogeneity. OBSDOSC is proposed in order to do some efforts to overcome some defects which current design tools usually have such as not user friendly and too professional. This paper proposes a pattern which describes the basic features of semi-automatic composite mode, discusses the whole lifetime of composed service and highlights how to lessen the descriptive heterogeneity and process heterogeneity and how to facilitate the design of composing a service.

A Testing Method for Web Services Composition Based on Data-Flow

This paper proposes a method of data-flow testing for Web services composition. Firstly, to facilitate data flow analysis and constraints collecting, the existing model representation of business process execution language （BPEL） is modified in company with the analysis of data dependency and an exact representation of dead path elimination （DPE） is proposed, which over-comes the difficulties brought to dataflow analysis. Then defining and using information based on data flow rules is collected by parsing BPEL and Web services description language （WSDL） documents and the def-use annotated control flow graph is created. Based on this model, data-flow anomalies which indicate potential errors can be discovered by traversing the paths of graph, and all-du-paths used in dynamic data flow testing for Web services composition are automatically generated, then testers can design the test cases according to the collected constraints for each path selected.

基于Web Services技术的分布式在线销售系统的开发与实现

基于Web Services的分布式计算系统的体系架构,利用Web Services与JZEE等技术,以Online Shopping为实例,开发了一个分布式应用系统,并验证了设计的Online Shopping实例的全部功能均可正常运行.该系统提供Web用户界面,具备诸如用户登记、商品目录与商品浏览等服务功能,便于消费者调用系统的内部Web服务的业务功能,通过Online Shopping的响应,获取所需的产品信息,并储存在数据库中.此外,Online Shopping也可以调用供应商的Web服务,将满足要求的订单发给供应商,从而实现产品供应商与自身系统之间的自动化的系统集成.

Android Web Services应用研究

该文介绍了在Android平台下如何使用ksoap2库来实现Web Services的功能,并介绍了Android的消息机制,及如何通过Handler来实现异步UI更新。

Analysis and modeling of web services flow using π-calculus

In order to increase the effectiveness and the reliability of web services flow, the ~r-calculus formal method is introduced as a development language for web services flow. The π-calculus overcomes inabilities of web service flow languages in demonstrating the consistency, validating the correctness and so on. The π- calculus analysis and modeling of web services flow is presented, the dynamic actions and basic activities of WS-BPEL with π-calculus formally are described, and the mapping from π-calculus expression to WS-BPEL is built. The basic construction of web services flow with the π-calculus method after the analysis of the syntax of WS-BPEL and inter-description between WS-BPEL and π-calculus is expressed. Also discussed are the approaches to web services flow by modeling from different views, and the proposed approaches through the development and modeling of an e-commerce web service flow application are illustrated.

MANUFACTURING SERVICE SYSTEM BASED ON WEB SERVICES FOR PARALLEL KINEMATICS MACHINES

Parallel kinematics machine （PKM） is advantageous over the serial machine tools in processing the complex-surface products. A manufacturing service system for PKM is developed to provide the services of the complex-surface machining for potential geographically-dispersed manufacturing enterprises. In order to easily in- tegrate the external system, Web services are used to encapsulate post-processing functions of PKM legacy sys- tems, including compilation, workspace calculation, interfere calibration, and kinematics transformation. A ser- vice-oriented architecture（SOA） is proposed for the cooperative work between the PKM system and its client. The workflow and the function module of this manufacturing service system are presented. An example shows that as a result of SOA and loose coupling, such a Web service-based manufacturing service system is easier to in- tegrate and interoperate with its client. Meanwhile, the system decreases the manufacturing cost and improves the efficiency than its former kind of distributed system.

基于Web Services的高校教学质量监控系统的分析与设计

结合目前高校教学管理的形势,将软件的开发结构B/S和C/S结合在一起,利用当前流行的开发工具和先进的技术设计基于Web Services的教学管理质量监控系统。把本系统柔和到校园网里,针对不同的对象把功能分别放在局域网和广域网中。

基于Web Services的校园教学资源整合的研究

针对高校信息化建设过程中普遍遇到的异构平台资源共享的问题,提出了一种基于Web services的教学资源整合框架。同时还介绍了Web Services的应用体系结构、相关技术和基于XML的教学资源描述方法。

基于Web Services的GIS与应用模型集成研究

分析GIS与应用模型集成的研究现状及存在的问题。针对存在的问题,提出基于Web Services的GIS与应用模型集成方法。具体定义应用模型服务体系及其与空间信息服务体系的关系,讨论基于服务链的GIS-ervices与应用模型服务集成服务链样式、集成实现过程、集成开发流程,给出基于服务集成实现小流域地貌演化问题计算的服务集成分析设计与实验结果。实验结果证明本文提出的基于Web Services的GIS与应用模型集成方法正确可行。

Multi-attribute group decision making algorithm for web services selection based on QoS

To address the problem of web services selection based on quality, an approach of multi-attribute group decision making algorithm is proposed. Based on the Borda social choice function, the group decision making algorithm aggregates the results of multiple methods with different principles which are used to obtain constantly changing quality of service, thus increasing the confidence to select the most appropriate web service for a special task. The experimental results indicate that the proposed approach has better scalability and can be applied to large-scale distributed service computing environments. It is also shown that the proposed group decision making approach can effectively optimize the services selection and outperforms the random and robin policies. By using this approach, it can extend a method to obtain constantly changing quality of service and construct a synthetic information entity with multi-level knowledge, which guarantees the accuracy of services selection.

基于Web Services的城市空间信息服务集成框架研究

设计了一个基于WebServices技术的、可实现城市空间信息服务集成与互操作的框架———π系统框架 .系统由 6个层次组成 :应用层、WWW服务层、Web空间应用集成层、空间应用集成服务层、元数据服务和空间信息服务层以及空间信息库层 .根据WAI的请求 ,AIS将不同的获取空间信息的服务和其他空间分析服务有机地集成起来 .系统给城市空间信息应用的开发者提供一个二次开发的平台和应用系统的基础框架 ,屏蔽了城市空间信息应用的分布性和GIS平台的异构性 .对于开发者来说 ,应用该框架进行二次开发 ,如同在网络中使用同一GIS平台开发一样 ,能够使用不同GIS厂商平台的空间分析服务 。

基于Web Services的企业应用集成技术及实现

企业应用集成是通过硬件、软件、标准和业务过程的结合,实现两个或多个企业系统之间的无缝集成,使它们能够统一运作。在分析传统的软件开发模式和系统集成方法所存在问题的基础上,提出了利用WebServices技术来实现企业应用集成的解决方案,并针对企业间供应链上企业应用集成的实际情况,给出了一个简化的供应链上企业应用集成的系统实例。