46,208 research outputs found

    О новом роде верхнепалеозойских растений Brovuchkia Parfenova gen. nov. из Кемеровского района Кузбасса

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    Multimedia information systems have been developed into service-ware. With the paradigms of web services, service oriented architectures (SOA), and Web 2.0 widgets, multimedia has become truly ubiquitous. However, interoperability, scalability, reliability and security are arising challenges at mobile multimedia service development. This paper focuses on the analysis, design, development and evaluation of a middleware that allows access from mobile devices to a bundle of multimedia services. The services are based on the international multimedia metadata description standard MPEG-7. The implementation is based on new generation of service-oriented application servers called Lightweight Application Server (LAS). Mobile web services refer to the fact that mobile servers host web services. A prototype was developed as a proof of concept, showing how to access MPEG-7 based multimedia services from a Mobile Host and the analysis results of providing MPEG-7 based multimedia services in the form of web services from the Mobile Host to other mobile devices. An alternative solution is to apply enterprise service bus technology as the middleware. The performance evaluation results of both approaches show the reliable accessibility of MPEG-7 based multimedia services via the enterprise service bus solution

    Fuzzy Based Optimal QoS Constraint Services Composition in Mobile Ad Hoc Networks

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    In recent years, computational capability of mobile devices such as Laptops, mobile phones, PDAs, etc., are greatly improved. Implementation of SOA ("Service Oriented Architectures") in mobile ad hoc networks increases the flexibility of using mobile devices. On composing different available services to satisfy end user requirement is a critical challenge in MANETs ("Mobile Ad Hoc Network") due to dynamic topology, Resource heterogeneity, Band width constraint and highly distributed service providers. Existing composition services approaches are not suitable for MANETs due to lack of constraints consideration while choosing services. In this paper, we proposed Fuzzy based optimal QoS constrained Service Composition in MANETs. We consider Energy constraint, hop count, Response time & service throughput as QoS Constraints composing optimal services. We proposed fuzzy logic based system to provide rating to the services for optimal selection of services. We also considered that each node can provide one or more services. The service composition failure rate will be reduced by selecting optimal services in available services. The simulation result demonstrates that the proposed method outperformed than the traditional AODV in terms of average packet delay, energy constraint, throughput and turnaround time

    Service Composition on a Mobile Phone

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    With the recent increase in interest in service-oriented architectures (SOA) and Web services, developing applications with the Web services paradigm has become feasible. Web services are self-describing, platform-independent computational elements. New applications can be assembled from a set of previously created Web services, which are composed together to make a service that uses its components to perform a certain task. This is the idea of service composition. To bring service composition to a mobile phone, I have created Interactive Service Composer for mobile phones. With Interactive Service Composer, the user is able to build service compositions on his mobile phone, consisting of Web services or services that are available from the mobile phone itself. The service compositions are reusable and can be saved in the phone's memory. Previously saved compositions can also be used in new compositions. While developing applications for mobile phones has been possible for some time, the usability of the solutions is not the same as when developing for desktop computers. When developing for mobile phones, the developer has to more carefully consider the decisions he is going to make with the program he is developing. With the lack of processing power and memory, the applications cannot function as well as on desktop PCs. On the other hand, this does not remove the appeal of developing applications for mobile devices

    A comparative analysis of adaptive middleware architectures based on computational reflection and aspect oriented programming to support mobile computing applications

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    Mobile computing applications are required to operate in environments in which the availability for resources and services may change significantly during system operation. As a result, mobile computing applications need to be capable of adapting to these changes to offer the best possible level of service to their users. However, traditional middleware is limited in its capability of adapting to environment changes and different users requirements. Computational Reflection and Aspect Oriented Programming paradigms have been used in the design and implementation of adaptive middleware architectures. In this paper, we propose two adaptive middleware architectures, one based on reflection and other based on aspects, which can be used to develop adaptive mobile applications. The reflection based architecture is compared to an aspect oriented based architecture from a quantitative perspective. The results suggest that middleware based on Aspect Oriented Programming can be used to build mobile adaptive applications that require less processor running time and more memory space than Computational Reflection while producing code that is easier to comprehend and modify.8th IFIP/IEEE International conference on Mobile and Wireless CommunicationRed de Universidades con Carreras en Informática (RedUNCI

    A demonstration case on the transformation of software architectures for service specification

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    This paper presents a demonstration case on the successive application of a model-based technique to assist on the refinement of software logical architectures. The technique is essentially based on the transformation of use cases into object diagrams. The applicability of the technique is illustrated by presenting some results from a mobile application. For mobile software, the definition of the underlying service-oriented architecture must consider as user requirements the services themselves, the mobile operators entry points and the final clients interfaces, and use them to characterize the platform. Within the presented demonstration case, the specification of one service of the mobile application was obtained by successively applying the technique.Research funded by FCT and FEDER under project STACOS (POSI/CHS/48875/2002)

    A Survey Paper on Service Oriented Architecture Approach and Modern Web Services

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    Service-Oriented Architecture is an architectural design pattern based on distinct pieces of software providing application functionality as services to other applications via a protocol. It is a collection of micro-services which are self-contained and provides unit functionality. The architectural style has the following essential core features which are inter-operability, service abstraction, service discovery, service autonomy, service statelessness re-usability, loose coupling. Service-oriented architectures are not a new thing. The first service-oriented architecture for many people in the past was with the use DCOM (uses RPC – Remote Procedural Calls) and CORBA (uses IIOP protocol) but because of the lack of standards and also with the advent of modern web development (Web 2.0) and the use of mobile phones and their penetration service oriented architecture is being implemented as Web Services (uses mainly HTTP/HTTPS) protocol. Most common implementations of Web Services can be done as SOAP (Simple Object Access Protocol)-based which essentially is a HTTP/HTTPS POST with an XML payload in it. SOAP based web services expose service interface using WSDL (Web Service Description Language) and there is a pre-defined contract via XSD (XML Schema Definition) between the service being exposed and the client side that consumes this service. The other most popular lightweight implementation of web services is using RESTful (Representational State Transfer) architecture where the payload is in JSON (Java Script Object Notation) / XML and uses RESTful style of communication to access resources on the server. So any application written in any language for example C# or C++ or C or Groovy or Java that can make a HTTP call should be able to access the services and since the data is in XML/JSON they can make a sense of data and this way we can re-use services and be inter-operable. The goal of our survey is to delve deeper into SOA principles, key constituents and how Web Services - implementation of SOA has taken this into such a wide spread usage and created a phenomena and various technologies that can be used to develop/consume web services and also about the protocols being used and some common use cases in building re-usable and scalable application architectures using web services

    Design and formal model of an event-driven and service-oriented architecture for the Mobile Tourist Information System TIP

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    This thesis introduces a new collaboration framework for context-aware services in a mobile environment enabling services to co-operate with several anonymous co-operation partners. We extend the current TIP design and architecture so that new services may easily be added to and co-operate with existing ones. Obsolete services may be replaced by new ones providing the same functionality. Services are de-coupled. Service co-operation is completely changed. This means that services react to the events they receive, irrespective of the events publishers. We also show how service-oriented and event-driven architectures may be combined maintaining their respective advantages. We introduce features of serviceoriented architectures to services co-operating via an eventbased middleware. We describe the formal model of a new system for mobile tourist information and the newly introduced features of the collaboration framework. Those features fundamentally change the way services communicate and cooperate

    Enabling Context-Aware Web Services: A Middleware Approach for Ubiquitous Environments

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    In ubiquitous environments, mobile applications should sense and react to environmental changes to provide a better user experience. In order to deal with these concerns, Service-Oriented Architectures (SOA) provide a solution allowing applications to interact with the services available in their surroundings. In particular, context-aware Web Services can adapt their behavior considering the user context. However, the limited resources of mobile devices restrict the adaptation degree. Furthermore, the diverse nature of context information makes difficult its retrieval, processing and distribution. To tackle these challenges, we present the CAPPUCINO platform for executing context-aware Web Services in ubiquitous environments. In particular, in this chapter we focus on the middleware part that is built as an autonomic control loop that deals with dynamic adaptation. In this autonomic loop we use FraSCAti, an implementation of the Service Component Architecture (SCA) specification, as the execution kernel for Web Services. The context distribution is achieved with SPACES, a flexible solution based on REST (REpresentational State Transfer ) principles and benefiting from the COSMOS (COntext entitieS coMpositiOn and Sharing ) context manage- ment framework. The application of our platform is illustrated with a mobile commerce application scenario that combines context-aware Web Services and social networks

    Prototype development of web services based on web service-oriented architectures / Norbaitee Arshad

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    Web service is the new technology that apply the techniques to reduce the time and cost of web application development. It uses the Service-oriented Architectures (SOA) as the basic architecture for web service development. Web service can be applied to many other technologies such as console application, mobile technology, window based application etc. This research focuses on the development of prototype of web services based on web service oriented architecture. It also involves the building the interaction between the elements of SOA architecture. This paper uses data from ILMU database provided by Perpustakaan Tun Abdul Razak (PTAR) and the dummy database. The scope focuses on the service to retrieve the reference information. The development of web service involves the several stages. The Java lanpiiage is used as the application language and the interface. The development tool is NetBeans IDE 5.5. The input parameter will be produced by the user in term keyword text. Keyword: Web service. Service-oriented Architectures (SOA), middleware, search engine, service-orientatio
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