Goal-Driven Context-aware Service Composition

Two important aspects are associated with service composition. One is to understand the needs and constraints for a new added-value composite service, and otherwise it would lead to an ad-hoc effort for service composition. The second is to reflect the changes of computing environment to the service composition to catch up the on-demand of users. This paper introduces a goal-driven approach to specify the user requirements and demands that guides the service composition, and proposes context awareness to adapt to a dynamically changing environment. Computing contexts, including physical context, user profile and computed results, are gathered by various services, and imported into an ontology based a context repository. A Goal Description Language, Context Condition/Effect are designed to describe the dynamic semantics of goal requirements and service capability. A planner is designed and implemented to dynamically compose services based on the current contexts, and a service runner is designed and implemented to invoke proper services based on the contexts and interactions with users. ?2010 IEEE.EI

Composition of context aware mobile services using a semantic context model

Context-awareness has been regarded as an important feature for mobile services. However, only a few services are sensible to context and the features that are context-aware are still limited. Composition of Web services has received much interest in business-to-business or enterprise application, but not so much interest in business-to- consumer applications. This paper presents iCas, a novel architecture that enables the creation of context-aware services on the fly, and discusses its main components. We compare our approach with similar systems and point out the main differences and advantages. To explore context-awareness to support service composition, iCas uses SeCoM, a semantic model to represent context. The main parts of this model are explained as well the advantages of using a semantic model to represent context. We also describe the use of our approach in an university campus to provide pedagogical features and assist the socio-pedagogical interaction of various types of users

Context constraint integration and validation in dynamic web service compositions

System architectures that cross organisational boundaries are usually implemented based on Web service technologies due to their inherent interoperability benets. With increasing exibility requirements, such as on-demand service provision, a dynamic approach to service architecture focussing on composition at runtime is needed. The possibility of technical faults, but also violations of functional and semantic constraints require a comprehensive notion of context that captures composition-relevant aspects. Context-aware techniques are consequently required to support constraint validation for dynamic service composition. We present techniques to respond to problems occurring during the execution of dynamically composed Web services implemented in WS-BPEL. A notion of context { covering physical and contractual faults and violations { is used to safeguard composed service executions dynamically. Our aim is to present an architectural framework from an application-oriented perspective, addressing practical considerations of a technical framework

A Context-aware Recommender System for Web Service Composition

[[abstract]]This study explored the use of context-aware recommender system to facilitate web service composition. The needs for composition of existing web services to generate functionality for users are increasing. And an intelligent framework is needed to alleviate users' burden to discover, select, invoke and combine web services. In this study, we focus on using context-aware recommender system to provide users with the most appropriate web services composition. The concept of context-aware collaborative filtering is used here to learn and predict user preferences, and based on this information, to compose necessary web services to achieve user request. We provide a restaurant recommender system prototype for the restaurant search scenario to demonstrate how proposed architecture works.[[conferencetype]]國際[[conferencedate]]20120718~20120720[[booktype]]紙本[[iscallforpapers]]Y[[conferencelocation]]Piraeus-Athens, Greec

Facilitating dynamic web service composition with fine-granularity context management

Context is an important factor for the success of dynamic service composition. Although many contextbased AI or workflow approaches have been proposed to support dynamic service composition, there is still an unaddressed issue of the support of fine-granularity context management. In this paper, we propose a granularity-based context model together with an approach to supporting the intelligent context-aware service composing problem. The corresponding case study is provided to show the validity of our approach.<br /

A model to design and verify context-aware adaptive service composition.

The introduction of mobile clients and context-aware behaviours intoWeb Service compositions may generate faults and inconsistencies. We introduce an extension of a composition model where context-awareness is made explicit and a number of correctness properties are verifiable. In particular, our extended model enables the verification of properties commonly used to validate context dependent applications. We also propose a set of algorithms to verify these properties efficiently

An Algorithm for Automatic Service Composition

Telecommunication companies are struggling to provide their users with value-added services. These services are expected to be context-aware, attentive and personalized. Since it is not economically feasible to build services separately by hand for each individual user, service providers are searching for alternatives to automate service creation. The IST-SPICE project aims at developing a platform for the development and deployment of innovative value-added services. In this paper we introduce our algorithm to cope with the task of automatic composition of services. The algorithm considers that every available service is semantically annotated. Based on a user/developer service request a matching service is composed in terms of component services. The composition follows a semantic graph-based approach, on which atomic services are iteratively composed based on services' functional and non-functional properties

PrimitiveC-ADL: Primitive Component Architecture Description Language

In this paper, we introduce an architecture descrip- tion language (ADL) for PCOMs (a context oriented component model). The language is described at three levels: (1) Building blocks (PCOMs context oriented components types) (2) Connec- tors, which connect components externally and internally, and (3) Architectural Configuration, which includes a full description of composition and decomposition mechanisms. The contribution is designing ADL. That supports context- orinted component by providing new architecture elements, which fulfil the requirements of designing context oriented component based applications. Context oriented component is a behavioural unit composed of static parts and dynamic parts. A PCOMs component model design was introduced in our previous work. PCOMs proposes a component model design to compose context-aware system by capturing context condition at runtime. The model is a component-based one that modifies the application architecture by subdividing components into subsystems of static and dynamic elements. We map each context condition to a composable template architectural configuration. Each context condition acts to select behavioural patterns, which combine to form application architectures. Different types of architecture elements are proposed in this work. We focus in defining the following new elements: Com- ponents’ dynamic and static parts, components’ layers, decision policies, and composition plan. Finally we introduce an ADL that fully supports context aware applications, by supporting the definition of a component as a unit of behaviour. Our ADL clearly defines the composition mechanisms, and provides proper definition for the composition’s design Patterns and composition plan. A Context oriented component is a behavioural unit composed with static parts and dynamic parts. A PCOMs component model design was introduced in our previous work. PCOMs proposes a component model design to compose context-aware system by capturing context condition at runtime. The model is a component-based one that modifies the application architecture by subdividing components into subsystems of static and dynamic elements. We map each context condition to a composable tem- plate architectural configuration. Each context condition acts to selected behavioural patterns, which combine to form application architectures

A new business model and architecture for context-aware applications provisioning in the cloud

Context-aware applications are seen as one of the killer application categories of the future, due to their ability to offer personalized services by adapting their behavior according to the users\u27 needs and changing situation. Context-aware applications rely in their operation on a complex set of functionalities (i.e. context-awareness substrates). In order to facilitate the development of novel context-aware applications and achieve efficiency in terms of resource utilization, there is a need for a unified, openly-accessible, scalable context management platform that enables the dynamic discovery, composition, and reuse of context-awareness substrates by various context-aware applications. The lack of such platform is a major impediment to the fast and resource efficient development of context aware applications. In this paper, we propose a novel virtualized context management platform in the cloud, in which a shared pool of virtualized context-awareness substrates can be offered by different providers, and leased on demand. Those substrates can be dynamically discovered and composed to enable fast and cost-effective development of a variety of context-aware applications. The proposed platform relies on a new business model which introduces the sensors substrate provider and the broker as new roles in the traditional cloud business model. A detailed software architecture and preliminary prototype implementation are also presented. © 2014 IEEE

Automated context aware composition of Advanced Telecom Services for environmental early warnings

This paper presents one of the main components of a framework for automated composition of Advanced Telecom Services for environmental early Warnings. The framework, called AUTO, is composed by three main modules: a request processing module that transforms natural language and context information into a planning instance; the automated planning module, based on PELEA, an architecture for planning and execution; and the Service Execution Environment Advance Telecom Services. This paper focuses on the description of the translation of the user request in natural language and his context into planning instances. These planning instances represent service composition tasks based on Automated Planning. The advantages of this approach, like the automatic inclusion of context and user preferences in the composition of services, will be presented. Also, the current implementation will be described and some experimentation will prove the viability of AUTO