Existing Web Services Research Articles

Improving Service-Oriented Architecture Processes in Process of Automatic Services Composition Using Memory and QF, QWV Factor

The application of service-orientated architecture in organizations for implementation of complicated workflows in electronic way using composite web services has become widespread. Thus, challenging research issues have also been raised in this regard. One of these issues is constructing composite web services by workflows. These workflows are composed of existing web services. Selections of a web service for each of workflow activities and fulfilling users’ conditions is still regarded as a major challenge. In fact, selection of a web service out of many such web services with identical function is a critical task which generally depends on composite evaluation tool of QoS. Previously proposed approaches do not consider exchange restrictions on the composition process and internal processes of architecture and previous experiences, and they ignore the fact that value of many of QoSs depends on the time of implementation. Selection of web services only based on QoS does not bring about optimal composite web service. Thus, till now, no solution has been proposed that performs composition process automatically or semi-automatically in optimal manner Objective: identification of existing concerns on composition of services and then designing a framework to provide a solution which consider all concerns and finally performing tests in order to examine and evaluate proposed framework Method: in the proposed framework, elements affecting management of service-oriented architecture processes are organized according to a logical procedure. This framework identifies processes of this style of architecture based on requirements in service-oriented architecture processes management and according to qualitative features in this area. In the proposed framework, in addition to using existing data in the problem area, existing structure and patterns in the area of software architecture are also utilize, and management processes in service-orientated architecture are improved based on propriety of available requirements. QWV are qualitative weighted dynamic features which indicate priority of users, and QF is quality factor of service at the time of implementation which is weighted in the framework. These factors are used for constructing composite web service. Multifactor computing is known as a natural computational system for automating the interaction between services. The factors in multi-agent systems can be used as the main reliable mechanism for the control which usually use data exchange for accelerating their evaluations. For identification of all concerns in the solution space, many aspects should be examined. To this end, classes of agents are defined which investigate these aspects in the form of four components using repository data. Results: proposed framework was simulated by Arena software and results showed this framework can be useful in automatic generation of needed services and meet all concerns at the same time. Results support that using agents in the model increased speed of accountability and satisfaction of users as well as system efficiency

An Effective Web Service Ranking Method via Exploring User Behavior

Service-oriented computing and Web services are becoming more and more popular, enabling organizations to use the Web as a market for selling their own Web services and consuming existing Web services from others. Nevertheless, with the increasing adoption and presence of Web services, it becomes more difficult to find the most appropriate Web service that satisfies both users’ functional and nonfunctional requirements. In this paper, we propose an effective Web service ranking approach based on collaborative filtering (CF) by exploring the user behavior, in which the invocation and query history are used to infer the potential user behavior. CF-based user similarity is calculated through similar invocations and similar queries (including functional query and QoS query) between users. Three aspects of Web services—functional relevance, CF based score, and QoS utility, are all considered for the final Web service ranking. To avoid the impact of different units, range, and distribution of variables, three ranks are calculated for the three factors respectively. The final Web service ranking is obtained by using a rank aggregation method based on rank positions. We also propose effective evaluation metrics to evaluate our approach. Large-scale experiments are conducted based on a real world Web service dataset. Experimental results show that the proposed approach outperforms the existing approach on the rank performance.

Non-deterministic planning methods for automated web service composition

Web service composition (WSC) is the task of generating new composite web services that exhibit functionalities not supported by any single web service. In its simplest form this is achieved by linking existing web services in sequence. More complex forms link services in parallel or use alternative paths. WSC can be considered a planning task, with the web services being the planning operators and the initial state and the goals being provided by the user. Particularly, since web services operate in a stochastic environment, their output is not predictable, and the problem is formulated as a non-deterministic planning one. This article presents a critical, comprehensive and up-to-date review of the literature concerning alternative non-deterministic planning methods, including probabilistic planning, determinization methods, planning in the belief state space and translation based methods. Furthermore, the article reviews existing implementations of WSC systems, employing a variety of planning approaches, and discusses the degree in which the current achievements from the non-deterministic planning field have been adopted successfully. To the best of our knowledge, this is the first review of its kind, one that provides a thorough introduction to the vast area of automated web service composition.

Integrating implicit feedbacks for time-aware web service recommendations

An increasing number of Web services have been published on the Internet over the past decade due to the rapid development and adoption of the SOA (Services Oriented Architecture) standard. However, in the current state of the Web, recommending suitable Web services to users becomes a challenge due to the huge divergence in published content. Existing Web services recommendation approaches based on collaborative filtering are mainly aiming to QoS (Quality of Service) prediction. Recommending services based on users' ratings on services are seldomly reported due to the difficulty of collecting such explicit feedback. In this paper, we report a data set of implicit feedback on real-world Web services, which consist of more than 280,000 user-service interaction records, 65,000 service users and 15,000 Web services or mashups. Temporal information is becoming an increasingly important factor in service recommendation since time effects may influence users' preferences on services to a large extent. Based on the collected data set, we propose a time-aware service recommendation approach. Temporal information is sufficiently considered in our approach, where three time effects are analyzed and modeled including user bias shifting, Web service bias shifting, and user preference shifting. Experimental results show that the proposed approach outperforms seven existing collaborative filtering approaches on the prediction accuracy.

GenomeD3Plot: a library for rich, interactive visualizations of genomic data in web applications.

Motivation: A simple static image of genomes and associated metadata is very limiting, as researchers expect rich, interactive tools similar to the web applications found in the post-Web 2.0 world. GenomeD3Plot is a light weight visualization library written in javascript using the D3 library. GenomeD3Plot provides a rich API to allow the rapid visualization of complex genomic data using a convenient standards based JSON configuration file. When integrated into existing web services GenomeD3Plot allows researchers to interact with data, dynamically alter the view, or even resize or reposition the visualization in their browser window. In addition GenomeD3Plot has built in functionality to export any resulting genome visualization in PNG or SVG format for easy inclusion in manuscripts or presentations.Results: GenomeD3Plot is being utilized in the recently released Islandviewer 3 (www.pathogenomics.sfu.ca/islandviewer/) to visualize predicted genomic islands with other genome annotation data. However, its features enable it to be more widely applicable for dynamic visualization of genomic data in general.Availability and implementation: GenomeD3Plot is licensed under the GNU-GPL v3 at https://github.com/brinkmanlab/GenomeD3Plot/.Contact: brinkman@sfu.ca

An adaptive agent-based system for deregulated smart grids

The power grid is undergoing a major change due mainly to the increased penetration of renewables and novel digital instruments in the hands of the end users that help to monitor and shift their loads. Such transformation is only possible with the coupling of an information and communication technology infrastructure to the existing power distribution grid. Given the scale and the interoperability requirements of such future system, service-oriented architectures (SOAs) are seen as one of the reference models and are considered already in many of the proposed standards for the smart grid (e.g., IEC-62325 and OASIS eMIX). Beyond the technical issues of what the service-oriented architectures of the smart grid will look like, there is a pressing question about what the added value for the end user could be. Clearly, the operators need to guarantee availability and security of supply, but why should the end users care? In this paper, we explore a scenario in which the end users can both consume and produce small quantities of energy and can trade these quantities in an open and deregulated market. For the trading, they delegate software agents that can fully interoperate and interact with one another thus taking advantage of the SOA. In particular, the agents have strategies, inspired from game theory, to take advantage of a service-oriented smart grid market and give profit to their delegators, while implicitly helping balancing the power grid. The proposal is implemented with simulated agents and interaction with existing Web services. To show the advantage of the agent with strategies, we compare our approach with the base agent one by means of simulations, highlighting the advantages of the proposal.

Manufacturing service composition method based on networked collaboration mode

“Cluster Supply Chains” (CSCs) are a new type of business mode, which can help small- and medium-sized enterprises (SMEs) to respond to the changing market demands effectively through networked collaboration. As a large number of manufacturers start to adopt the emerging services paradigm, various cross-enterprise business collaborations in CSC can be deemed as the manufacturing service composition (MSC). However, existing web service composition methods are not appropriate for satisfying the specific demands of manufacturing services composition. The reason lies in two aspects: (1) Current Quality of Service (QoS) model cannot consider the horizontal collaboration between manufacturing services, which may ignore a lot of potential candidate services; (2) current methods are not good at dealing with the rapid increase of candidate service set, which need to be improved further in the searching capability. To solve the above problems, this paper first proposes the new QoS evaluation model of manufacturing service composition according to the networked collaboration pattern in CSC; secondly, the Genetic-Artificial Bee Colony (G-ABC) algorithm is proposed to enhance the performance of searching for the optimal solution based on the available horizontal composite service; finally, the effectiveness of the above solutions is validated through simulation experiments and the results are satisfactory.

Quality of Experience: User's Perception about Web Services

Web service composition enables seamless and dynamic integration of Web services. The behavior of participant Web services determines the overall performance of a composition. Therefore, it is important to choose high quality services for service composition. Existing Web service selection and discovery approaches rely on non-functional aspects (also known as quality of service or QoS), e.g., response time and availability. Though these parameters are crucial for selecting Web services, they may not reflect the user's perspective of quality. In this paper, we explore the feasibility of incorporating perceived quality from user's perspective for service selection and composition. We name such quality attributes as quality of experience (QoE). First, we propose a solution that automatically mines and identifies QoE attributes from the Web. Second, we study the application of such dynamically extracted QoE attributes for service selection. For the evaluation purpose, we collected more than 34,000 reviews from 58 different services in six domains. Our findings show that it is possible to automatically identify QoE attributes with an average precision and recall of 92 and 80 percent respectively. Our study shows that there is a strong positive correlation between QoS and QoE. Hence QoE can be used during service selection especially when QoS data are not available. Furthermore, we found 70 percent of service discovery queries indeed contain QoE attributes showing the importance of QoE attributes during the service discovery phase.

Unified Collaborative and Content-Based Web Service Recommendation

The last decade has witnessed a tremendous growth of web services as a major technology for sharing data, computing resources, and programs on the web. With increasing adoption and presence of web services, designing novel approaches for efficient and effective web service recommendation has become of paramount importance. Most existing web service discovery and recommendation approaches focus on either perishing UDDI registries, or keyword-dominant web service search engines, which possess many limitations such as poor recommendation performance and heavy dependence on correct and complex queries from users. It would be desirable for a system to recommend web services that align with users’ interests without requiring the users to explicitly specify queries. Recent research efforts on web service recommendation center on two prominent approaches: <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">collaborative filtering</i> and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> content-based recommendation</i> . Unfortunately, both approaches have some drawbacks, which restrict their applicability in web service recommendation. In this paper, we propose a novel approach that unifies collaborative filtering and content-based recommendations. In particular, our approach considers simultaneously both rating data (e.g., QoS) and semantic content data (e.g., functionalities) of web services using a probabilistic generative model. In our model, unobservable user preferences are represented by introducing a set of latent variables, which can be statistically estimated. To verify the proposed approach, we conduct experiments using 3,693 real-world web services. The experimental results show that our approach outperforms the state-of-the-art methods on recommendation performance.

Embedded Real-Time HTTP Server

This paper presents the architecture of embedded real-time web server. Unlike existing web servers, in our approach, requests are processed not in the “first in first out” order but according to their deadlines and the expected server load. For this purpose the Least Laxity First scheduling method is used. First, requests with imposed hard real-time constraints are served. Then requests enclosed by soft deadlines are processed. Finally, request without time requirements are served in the order they arrived. We also present real-time extensions to the Hypertext Transfer Protocol. We propose headers that enable defining hard and soft deadlines, as well as responses containing time information, that are being sent to the client application. The experimental results showed that in case of real-time applications our server misses significantly fewer requests, due to time out, then existing solutions. The presented server may be very useful for implementing real-time services supported by embedded systems, e.g. in future real-time “Internet of things” applications.

Formal specification of flexible web service composition

Web services give a standard way for interface definition, transport mechanism, description, discovery and integration of services. Although the heterogeneity among applications is reduced, mismatches may occur at different levels structural, behavioural and non-functional during web services composition process. These mismatches require adaptation to ensure the correct working between web services. In this paper, we propose an approach for dynamic web service composition and adaptation. We specify formally the flexible web service composition FWSC using a rewriting logic-based language namely Maude. We show how to adapt the interfaces of existing web services without having to operate on the source manually. As a result, existing web services may be easily reused in a broader range of applications, and services libraries do not need to store many variants of a component that differ only in how the interfaces are used.

A novel verification model for web services manoeuvring using hybrid automata

Service oriented architecture SOA is realised by independent, standardised and self-describing units known as services. Web service composition is the creation of new value added services by incorporating some existing web services together. For verifying the composed web services, a holistic view of what aspects of a service need to be specified is still lacking. A few research works have been carried out in the past for verifying the composed web services for a deterministic system. The existing verification model did not address the issues like departed transition and deadlocks recovery significantly. This paper proposes a hybrid automata HA model by combining the amend Muller automata AMA and push down automata PDA to verify the composed web services for both deterministic and non-deterministic systems. Departed transition and deadlock recovery algorithm has been proposed. We show an example to demonstrate the meticulousness of the model. The experimental results show that the performance of the proposed model is measured efficiently.

Formal Specification of the Assurance Point Web Service Composition Model

This paper presents a formal specification of the Assurance Point (AP) web service composition model. The AP model provides a flexible way of checking constraints and responding to execution errors in service composition. An AP is a combined logical and physical checkpoint, providing an execution milestone that stores critical data and interacts with integration rules (IRs) to alter program flow and to invoke different forms of recovery depending on the execution status. In this paper, the execution and recovery semantics of assurance points have been fully defined in the context of if-else, parallel, and loop control structures. The activities and complex control structures of the AP model have been formalized and tested in the Yet Another Workflow Language (YAWL) engine. By doing so, the correctness of the execution and recovery semantics in the AP model has been verified, demonstrating that YAWL nets of the AP model satisfy the soundness property. Different from existing web service composition models, the AP model presented by this research provides multiple levels of protection against service execution failure with a combination of forward and backward recovery techniques.

Unified and isomer-specific NMR metabolomics database for the accurate analysis of (13)C-(1)H HSQC spectra.

A new metabolomics database and query algorithm for the analysis of 13C–1H HSQC spectra is introduced, which unifies NMR spectroscopic information on 555 metabolites from both the Biological Magnetic Resonance Data Bank (BMRB) and Human Metabolome Database (HMDB). The new database, termed Complex Mixture Analysis by NMR (COLMAR) 13C–1H HSQC database, can be queried via an interactive, easy to use web interface at http://spin.ccic.ohio-state.edu/index.php/hsqc/index. Our new HSQC database separately treats slowly exchanging isomers that belong to the same metabolite, which permits improved query in cases where lowly populated isomers are below the HSQC detection limit. The performance of our new database and query web server compares favorably with the one of existing web servers, especially for spectra of samples of high complexity, including metabolite mixtures from the model organisms Drosophila melanogaster and Escherichia coli. For such samples, our web server has on average a 37% higher accuracy (true positive rate) and a 82% lower false positive rate, which makes it a useful tool for the rapid and accurate identification of metabolites from 13C–1H HSQC spectra at natural abundance. This information can be combined and validated with NMR data from 2D TOCSY-type spectra that provide connectivity information not present in HSQC spectra.

Orchestration in Distributed Web-of-Objects for Creation of User-Centered IoT Service Capability

While advancing to a new concept of service it is essential to consider the integration of various objects which are already exists and services being provided with well-established technologies. In order to provide user based IoT service, this paper aims to suggest the construction of Web-of-Objects platform in the IoT service environment. Within the WoO platform, it provides user-centered IoT service with device profile objectification and semantic ontology based service orchestration between existing web service and device objectification. The use case elaborates the user-centered significant in Smart Home service and Smart Building service using WoO platform.

PHAT: A Preference and Honesty Aware Trust Model for Web Services

Trust is one of the most critical factors for a service requestor when selecting a service from a large pool of candidate services. However, existing web service trust models either do not consider users' preferences for different quality of service (QoS) attributes, or ignore the impact of vicious ratings on trust evaluation. To address these gaps, PHAT, a dynamic trust evaluation model with dual consideration of users' preferences and false ratings, is proposed in this paper. The model introduces an approach to automatically mine users' preferences from their requirements. The preferences are then used to determine the weight of each QoS attribute when integrating trust into multi-dimensional QoS attributes. The “local” trust on a service is derived by combining the trust on QoS attributes and the user's subjective ratings. Then, the users are divided into different groups according to their QoS preferences, and the honesty of each group is assessed by filtering out dishonest users based on a hybrid approach combining rating consistency clustering with an average method. Finally, the weight on ratings is dynamically adjusted according to the results of honesty assessment when calculating the global trustworthiness, namely, the reputation of a service. The proposed model is evaluated with real-world QoS data, and the results indicate that PHAT works well on personalized evaluation of trust, and can effectively dilute the influence of malicious ratings.

SEMANTIC ENHANCED UDDI USING OWL-S PROFILE ONTOLOGY FOR THE AUTOMATIC DISCOVERY OF WEB SERVICES IN THE DOMAIN OF TELECOMMUNICATION

The current web services which are evolved in the telecom domain such as payment web services, Yellow pages web services, operator web services, weather web services are failed to bring down the semantic as they used to prove its syntactic description. The reason for bringing down the semantic description into already existing web services will invoke certain operations like automatic discovery of web services, automatic composition of the necessary services, automatic invocation of web services and automatic monitoring of the execution process. At present the web services in the domain of telecommunication is following the parlay X standard. The parlay X has given a set of standard web service API’s for the telecom. The each of the services will have its own interface, services and types In this study in order to bring down the semantic representation we have proposed an idea to enable the semantic through the upper ontology like OWL-S and then how to map OWL-S to UDDI registry and also we have discussed some of the issues that we have faced while mapping OWL-S into UDDI registry. So the approach which we are going to propose improves the accuracy of the telecommunication network services description, discovery and matching, unifies the semantic representation of telecommunications network and Internet services.

From User's Goal to Semantic Web Services Discovery

The growing number of the Web Services available on the Web without explicit associated semantic descriptions raises a new and challenging research problem: How to discover efficiently the relevant Web Services that fulfill the user expectations. However, many services that are relevant to a specific user service request may not be considered during the service discovery process. In this paper, the authors address the issue of the Web Service discovery given nonexplicit service description semantics that match a specific service request. Their approach is based on a captured user goal from an HTML form and the traceability and involves semantic-based service categorization, semantic discovery and selection of the best Web Service. Furthermore, the authors' proposal employs ontology matching algorithms to match a specific goal to an existing Web Service. An experimental test of the proposed framework related to the Medical Analysis domain is reported, showing the impact of the proposal in decreasing the time and the effort of the discovery process as a whole.

Formal Verification of WS-BPEL Using Timed Trace Theory

A web service composition is able to create a new service by incorporating some existing web services. Currently, Web Service Business Process Execution Language or WS-BPEL is a promising language used to describe the web service composition. Since in the real world most of business processes have been involved temporal context and they are quite complex interaction, it is impossible to completely eliminate all failures in them. Therefore, a formal verification is required to assure the correctness and reliability of the web service composition. In this paper, timed trace theory has been applied to verify the web service composition with temporal constraints. Both safety and timing failures can be examined. Experimenting with a ticket reservation system, the proposed approach shows its effectiveness.

Design of access control system for telemedicine secure XML documents

XML can supply the standard data type in information exchange format on a lot of data generated in running database or applied programs for a company by using the advantage that it can describe meaningful information directly. Accordingly since there are increasing needs for the efficient management and telemedicine security of the massive volume of XML data, it is necessary to develop a secure access control mechanism for XML. The existing access control has not taken information structures and semantics into full consideration due to the fundamental limitations of HTML. In addition, access control for XML documents allows read operations only, and there are problems of slowing down the system performance due to the complex authorization evaluation process. To resolve this problem, this paper designs and builds a XACS (XML Access Control System), which is capable of making fined-grained access control. This only provides data corresponding to its users' authority levels by authorizing them to access only the specific items of XML documents when they are searching XML documents in telemedicine. To accomplish this, XACS eliminates certain parts of the documents that are inaccessible and transmits the parts accessible depending on the users' authority levels. In addition, it can be expanded to existing web servers because XML documents are used based on the normal web sites. The telemedicine secure and the guidelines are provided to enable quick and precise understanding of the information, and thus the safety enhancement gets improved. Ultimately, this paper suggests an empirical telemedicine application to confirm the adequacy and validity using the proposed method.