Engine

Distribution by Scientific Domains
Distribution within Engineering

Kinds of Engine

  • combustion engine
  • diesel engine
  • internal combustion engine
  • search engine
  • turbofan engine

  • Terms modified by Engine

  • engine component
  • engine performance

  • Selected Abstracts


    Generate and Repair Machine Translation

    COMPUTATIONAL INTELLIGENCE, Issue 3 2002
    Kanlaya Naruedomkul
    We propose Generate and Repair Machine Translation (GRMT), a constraint,based approach to machine translation that focuses on accurate translation output. GRMT performs the translation by generating a Translation Candidate (TC), verifying the syntax and semantics of the TC and repairing the TC when required. GRMT comprises three modules: Analysis Lite Machine Translation (ALMT), Translation Candidate Evaluation (TCE) and Repair and Iterate (RI). The key features of GRMT are simplicity, modularity, extendibility, and multilinguality. An English,Thai translation system has been implemented to illustrate the performance of GRMT. The system has been developed and run under SWI,Prolog 3.2.8. The English and Thai grammars have been developed based on Head,Driven Phrase Structure Grammar (HPSG) and implemented on the Attribute Logic Engine (ALE). GRMT was tested to generate the translations for a number of sentences/phrases. Examples are provided throughout the article to illustrate how GRMT performs the translation process. [source]


    The Role of Effective Modeling in the Development of Self-Efficacy: The Case of the Transparent Engine,

    DECISION SCIENCES JOURNAL OF INNOVATIVE EDUCATION, Issue 1 2007
    Kevin P. Scheibe
    ABSTRACT Computing technology augments learning in education in a number of ways. One particular method uses interactive programs to demonstrate complex concepts. The purpose of this article is to examine one type of interactive learning technology, the transparent engine. The transparent engine allows instructors and students to view and directly interact with educational concepts such as Web-enabled software development. The article first presents a framework describing transparent engines. The framework details four types of transparent engines: (1) enactive mastery/manipulatable, (2) enactive mastery/nonmanipulatable, (3) vicarious experience/manipulatable, and (4) vicarious experience/nonmanipulatable. Following this, we present the results of an experiment designed to examine this framework by testing its predictions for one quadrant, vicarious experience/nonmanipulatable. The results support the framework in that students taught concepts with the aid of the vicarious experience/nonmanipulatable transparent engine had significantly higher domain-specific self-efficacy compared to those taught the same concepts without this tool. [source]


    Effectiveness of arthroscopic versus open surgical stabilisation for the management of traumatic anterior glenohumeral instability

    INTERNATIONAL JOURNAL OF EVIDENCE BASED HEALTHCARE, Issue 2 2007
    Choong Ng BMedSci(Melb)
    Abstract Background, Anterior instability is a frequent complication following a traumatic glenohumeral dislocation. Frequently the underlying pathology associated with recurrent instability is a Bankart lesion. Surgical correction of Bankart lesions and other associated pathology is the key to successful treatment. Open surgical glenohumeral stabilisation has been advocated as the gold standard because of consistently low postoperative recurrent instability rates. However, arthroscopic glenohumeral stabilisation could challenge open surgical repair as the gold standard treatment for traumatic anterior glenohumeral instability. Objectives, Primary evidence that compared the effectiveness of arthroscopic versus open surgical glenohumeral stabilisation was systematically collated regarding best-practice management for adults with traumatic anterior glenohumeral instability. Search strategy, A systematic search was performed using 14 databases: MEDLINE, Cumulative Index of Nursing and Allied Health (CINAHL), Allied and Complementary Medicine Database (AMED), ISI Web of Science, Expanded Academic ASAP, Proquest Medical Library, Evidence Based Medicine Reviews, Physiotherapy Evidence Database, TRIP Database, PubMed, ISI Current Contents Connect, Proquest Digital Dissertations, Open Archives Initiative Search Engine, Australian Digital Thesis Program. Studies published between January 1984 and December 2004 were included in this review. No language restrictions were applied. Selection criteria, Eligible studies were those that compared the effectiveness of arthroscopic versus open surgical stabilisation for the management of traumatic anterior glenohumeral instability, which had more than 2 years of follow up and used recurrent instability and a functional shoulder questionnaire as primary outcomes. Studies that used non-anatomical open repair techniques, patient groups that were specifically 40 years or older, or had multidirectional instability or other concomitant shoulder pathology were excluded. Data collection and analysis, Two independent reviewers assessed the eligibility of each study for inclusion into the review, the study design used and its methodological quality. Where any disagreement occurred, consensus was reached by discussion with an independent researcher. Studies were assessed for homogeneity by considering populations, interventions and outcomes. Where heterogeneity was present, synthesis was undertaken in a narrative format; otherwise a meta-analysis was conducted. Results, Eleven studies were included in the review. Two were randomised controlled trials. Evidence comparing arthroscopic and open surgical glenohumeral stabilisation was of poor to fair methodological quality. Hence, the results of primary studies should be interpreted with caution. Observed clinical heterogeneity in populations and outcomes was highlighted and should be considered when interpreting the meta-analysis. Authors also used variable definitions of recurrent instability and a variety of outcome measures, which made it difficult to synthesise results. When comparable data were pooled, there were no significant differences (P > 0.05) between the arthroscopic and open groups with respect to recurrent instability rates, Rowe score, glenohumeral external rotation range and complication rates. Conclusions, Statistically, it appears that both surgical techniques are equally effective in managing traumatic anterior glenohumeral instability. In light of the methodological quality of the included studies, it is not possible to validate arthoscopic stabilisation to match open surgical stabilisation as the gold standard treatment. Further research using multicentred randomised controlled trials with sufficient power and instability-specific questionnaires with sound psychometric properties is recommended to build on current evidence. The choice of treatment should be based on multiple factors between the clinician and the patient. [source]


    Lack of evidence of the effectiveness of primary brachial plexus surgery for infants (under the age of two years) diagnosed with obstetric brachial plexus palsy

    INTERNATIONAL JOURNAL OF EVIDENCE BASED HEALTHCARE, Issue 4 2006
    Andrea Bialocerkowski PhD M App Sc (Physio) M App Sc (Physio) Grad Dip Public Health
    Abstract Background, Obstetric brachial plexus palsy, which occurs in 1,3 per 1000 live births, results from traction and/or compression of the brachial plexus in utero, during descent through the birth canal or during delivery. This results in a spectrum of injuries that range in extent of damage and severity and can lead to a lifelong impairment and functional difficulties associated with the use of the affected upper limb. Most infants diagnosed with obstetric brachial plexus palsy receive treatment, such as surgery to the brachial plexus, physiotherapy or occupational therapy, within the first months of life. However, there is controversy regarding the most effective form of management. This review follows on from our previous systematic review which investigated the effectiveness of primary conservative management in infants with obstetric brachial plexus palsy. This systematic review focuses on the effects of primary surgery. Objectives, The objective of this review was to systematically assess and collate all available evidence on effectiveness of primary brachial plexus surgery for infants with obstetric brachial plexus palsy. Search strategy, A systematic literature search was performed using 13 databases: TRIP, MEDLINE, CINAHL, Web of Science, Proquest 5000, Evidence Based Medicine Reviews, Expanded Academic ASAP, Meditext, Science Direct, the Physiotherapy Evidence Database, Proquest Digital Dissertations, Open Archives Initiative Search Engine, the Australian Digital Thesis program. Those studies that were reported in English and published between July 1992 to June 2004 were included in this review. Selection criteria, Quantitative studies that investigated the effectiveness of primary brachial plexus surgery for infants with obstetric brachial plexus palsy were eligible for inclusion into this review. This excluded studies where infants were solely managed conservatively or with pharmacological agents, or underwent surgery for the management of secondary deformities. Data collection and analysis, Two independent reviewers assessed the eligibility of each study for inclusion into the review, the study design used and its methodological quality. Where any disagreement occurred, consensus was reached by discussion. Studies were also assessed for clinical homogeneity by considering populations, interventions and outcomes. Where heterogeneity was present, synthesis was undertaken in a narrative format. Results, Twenty-one studies were included in the review. Most were ranked low on the hierarchy of evidence (no randomised controlled trials were found), and most had only fair methodological quality. Surgical intervention was variable, as were the eligibility criteria for surgery, the timing of surgery and the outcome instruments used to evaluate the effect of surgery. Therefore, it is difficult to draw conclusions regarding the effectiveness of primary brachial plexus surgery for infants with obstetric brachial plexus palsy. Conclusions, Although there is a wealth of information regarding the outcome following primary brachial plexus surgery it was not possible to determine whether this treatment is effective in increasing functional recovery in infants with obstetric brachial plexus palsy. Further research is required to develop standardised surgical criteria, and standardised outcome measures should be used at specific points in time during the recovery process to facilitate comparison between studies. Moreover, comparison groups are required to determine the relative effectiveness of surgery compared with other forms of management. [source]


    Effectiveness of primary conservative management for infants with obstetric brachial plexus palsy

    INTERNATIONAL JOURNAL OF EVIDENCE BASED HEALTHCARE, Issue 2 2005
    Andrea Bialocerkowski PhD MAppSc(Phty) GradDipPublicHealth
    Executive summary Background, Obstetric brachial plexus palsy, a complication of childbirth, occurs in 1,3 per 1000 live births internationally. Traction and/or compression of the brachial plexus is thought to be the primary mechanism of injury and this may occur in utero, during the descent through the birth canal or during delivery. This results in a spectrum of injuries that vary in severity, extent of damage and functional use of the affected upper limb. Most infants receive treatment, such as conservative management (physiotherapy, occupational therapy) or surgery; however, there is controversy regarding the most appropriate form of management. To date, no synthesised evidence is available regarding the effectiveness of primary conservative management for obstetric brachial plexus palsy. Objectives, The objective of this review was to systematically assess the literature and present the best available evidence that investigated the effectiveness of primary conservative management for infants with obstetric brachial plexus palsy. Search strategy, A systematic literature search was performed using 14 databases: TRIP, MEDLINE, CINAHL, AMED, Web of Science, Proquest 5000, Evidence Based Medicine Reviews, Expanded Academic ASAP, Meditext, Science Direct, Physiotherapy Evidence Database, Proquest Digital Dissertations, Open Archives Initiative Search Engine, Australian Digital Thesis Program. Those studies that were reported in English and published over the last decade (July 1992 to June 2003) were included in this review. Selection criteria, Quantitative studies that investigated the effectiveness of primary conservative management for infants with obstetric brachial plexus palsy were eligible for inclusion in this review. This excluded studies that solely investigated the effect of primary surgery for these infants, management of secondary deformities and the investigation of the effects of pharmacological agents, such as botulinum toxin. Data collection and analysis, Two independent reviewers assessed the eligibility of each study for inclusion into the review, the study design used and its methodological quality. Where any disagreement occurred, consensus was reached by discussion. Studies were assessed for clinical homogeneity by considering populations, interventions and outcomes. Where heterogeneity was present, synthesis was undertaken in a narrative format. Results, Eight studies were included in the review. Most were ranked low on the Hierarchy of Evidence (no randomised controlled trials were found), and had only fair methodological quality. Conservative management was variable and could consist of active or passive exercise, splints or traction. All studies lacked a clear description of what constituted conservative management, which would not allow the treatment to be replicated in the clinical setting. A variety of outcome instruments were used, none of which had evidence of validity, reliability or sensitivity to detect change. Furthermore, less severely affected infants were selected to receive conservative management. Therefore, it is difficult to draw conclusions regarding the effectiveness of conservative management for infants with obstetric brachial plexus palsy. Conclusions, There is scant, inconclusive evidence regarding the effectiveness of primary conservative intervention for infants with obstetric brachial plexus palsy. Further research should be directed to develop outcome instruments with sound psychometric properties for infants with obstetric brachial plexus palsy and their families. These outcome instruments should then be used in well-designed comparative studies. [source]


    Performance of Four Ceramic-Matrix Composite Divergent Flap Inserts Following Ground Testing on an F110 Turbofan Engine

    JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 7 2000
    James M. Staehler
    Four ceramic-matrix composite flap inserts were evaluated following ground testing on a General Electric F110 turbofan engine. Three of the composites accumulated ,117 h of engine time. The fourth composite, a NextelTM 720 material with aluminosilicate matrix, accumulated ,40 h. Large through-thickness cracks developed along the longitudinal edges of a NicalonÔ/Al2O3 insert and the Nextel 720/aluminosilicate insert. The cracks developed because of high tensile stresses caused by the steep in-plane thermal gradients induced across the flap width during afterburner lights. The Nextel 720/aluminosilicate insert also exhibited severe surface wear associated with the acoustic environment and contact with the adjacent divergent seals. Neither a Nicalon/silicon nitrocarbide insert nor a Nicalon/C insert exhibited significant signs of distress. [source]


    The Keys to Milton's "Two-Handed Engine" in Lycidas (1637)

    MILTON QUARTERLY, Issue 2 2010
    James Kelly
    First page of article [source]


    The Americans With Disabilities Act as Engine of Social Change: Models of Disability and the Potential of a Civil Rights Approach

    POLICY STUDIES JOURNAL, Issue 4 2001
    Andrew I. Batavia
    The Americans With Disabilities Act, based on the civil rights/minority group and independent living models of disability, may enhance access to health care, personal assistance, employment, the electoral process, and smoke-free environments for people with disabilities. However, this essential law cannot resolve these key issues. Supplemental theoretical and policy approaches will be necessary to promote fundamental change. [source]


    Toward Web 2.0 music information retrieval: Utilizing emotion-based, user-assigned descriptors

    PROCEEDINGS OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE & TECHNOLOGY (ELECTRONIC), Issue 1 2007
    Hyuk-Jin Lee
    This exploratory, preliminary study seeks to determine whether the use of emotion-based, user-assigned descriptors elicited from music information retrieval (MIR) system users could improve access and retrieval for a browsing-based MIR system within the Web 2.0 environment. We used the Glass Engine, a Web-based tool designed for exploring Philip Glass' music, as the basis for conceptualizing this study. The Glass Engine allows users to browse several facets of Glass' music via direct manipulation (sliding bars). [source]


    Ladder of Opportunity or Engine of Inequality?

    THE POLITICAL QUARTERLY, Issue 2006
    RUTH LISTER
    First page of article [source]


    Thomas the Tank Engine and Friends improve the understanding of oxygen delivery and the pathophysiology of hypoxaemia,

    ANAESTHESIA, Issue 11 2006
    J. F. Cosgrove
    Summary Understanding basic pathophysiological principles underpins the practice of many healthcare workers, particularly in a critical care setting. Undergraduate curricula have the potential to separate physiology teaching from clinical contexts, making understanding difficult. We therefore assessed the use of analogous imagery as an aid to understanding. Two groups of first year physiotherapy students were randomly assigned to receive either a control lecture (oxygen delivery and hypoxaemia) or a study lecture (control lecture plus images of a train set delivering rocks: an analogy to oxygen delivery.) Qualitative assessment of the lectures showed a significant (p < 0.001) improvement in understanding by the study group, and increased the proportion of students that found the lecture ,interesting and stimulating' (p = 0.01). Quantitative assessment demonstrated a significant increase in the multiple choice questionnaire marks of the study group (p = 0.03). In conclusion, analogous imagery can significantly increase the understanding of this physiological concept. [source]


    A performance study of job management systems

    CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 13 2004
    Tarek El-Ghazawi
    Abstract Job Management Systems (JMSs) efficiently schedule and monitor jobs in parallel and distributed computing environments. Therefore, they are critical for improving the utilization of expensive resources in high-performance computing systems and centers, and an important component of Grid software infrastructure. With many JMSs available commercially and in the public domain, it is difficult to choose an optimum JMS for a given computing environment. In this paper, we present the results of the first empirical study of JMSs reported in the literature. Four commonly used systems, LSF, PBS Pro, Sun Grid Engine/CODINE, and Condor were considered. The study has revealed important strengths and weaknesses of these JMSs under different operational conditions. For example, LSF was shown to exhibit excellent throughput for a wide range of job types and submission rates. Alternatively, CODINE appeared to outperform other systems in terms of the average turn-around time for small jobs, and PBS appeared to excel in terms of turn-around time for relatively larger jobs. Copyright © 2004 John Wiley & Sons, Ltd. [source]


    The Value of Remanufactured Engines: Life-Cycle Environmental and Economic Perspectives

    JOURNAL OF INDUSTRIAL ECOLOGY, Issue 1-2 2004
    Vanessa M. Smith
    Remanufacturing restores used automotive engines to like-new condition, providing engines that are functionally equivalent to a new engine at much lower environmental and economic costs than the manufacture of a new engine. A life-cycle assessment (LCA) model was developed to investigate the energy savings and pollution prevention that are achieved in the United States through remanufacturing a midsized automotive gasoline engine compared to an original equipment manufacturer manufacturing a new one. A typical full-service machine shop, which is representative of 55% of the engine remanufacturers in the United States, was inventoried, and three scenarios for part replacement were analyzed. The life-cycle model showed that the remanufactured engine could be produced with 68% to 83% less energy and 73% to 87% fewer carbon dioxide emissions. The life-cycle model showed significant savings for other air emissions as well, with 48% to 88% carbon monoxide (CO) reductions, 72% to 85% nitrogen oxide (NOx) reductions, 71% to 84% sulfur oxide (SOx) reductions, and 50% to 61% nonmethane hydrocarbon reductions. Raw material consumption was reduced by 26% to 90%, and solid waste generation was reduced by 65% to 88%. The comparison of environmental burdens is accompanied by an economic survey of suppliers of new and remanufactured automotive engines showing a price difference for the consumer of between 30% and 53% for the remanufactured engine, with the greatest savings realized when the remanufactured engine is purchased directly from the remanufacturer. [source]


    Changing Engines of Growth in China: From Exports, FDI and Marketization to Innovation and Exports

    CHINA AND WORLD ECONOMY, Issue 2 2008
    Furong Jin
    O30; O40; R11 Abstract This paper investigates the changing sources of growth in post-reform China. Using cross-province regressions, this paper finds that, in earlier periods, exports, foreign direct investment and marketization were significantly related to per capita income growth, whereas since the late 1990s, foreign direct investment and marketization have lost their significance and have been replaced by new sources of growth, such as innovation and knowledge, with only exports continuing to be important. This finding is robust after controlling for other variables representing other economic policies and provincial characteristics. We also tackle the possible endogeneity of innovation variables using the instrumental variables estimation method. [source]


    SEARCHING FOR EXPLANATORY WEB PAGES USING AUTOMATIC QUERY EXPANSION

    COMPUTATIONAL INTELLIGENCE, Issue 1 2007
    Manabu Tauchi
    When one tries to use the Web as a dictionary or encyclopedia, entering some single term into a search engine, the highly ranked pages in the result can include irrelevant or useless sites. The problem is that single-term queries, if taken literally, underspecify the type of page the user wants. For such problems automatic query expansion, also known as pseudo-feedback, is often effective. In this method the top n documents returned by an initial retrieval are used to provide terms for a second retrieval. This paper contributes, first, new normalization techniques for query expansion, and second, a new way of computing the similarity between an expanded query and a document, the "local relevance density" metric, which complements the standard vector product metric. Both of these techniques are shown to be useful for single-term queries, in Japanese, in experiments done over the World Wide Web in early 2001. [source]


    Integrating Web-Based Documents, Shared Knowledge Bases, and Information Retrieval for User Help

    COMPUTATIONAL INTELLIGENCE, Issue 1 2000
    Doug Skuce
    We describe a prototype system, IKARUS, with which we investigated the potential of integrating web-based documents, shared knowledge bases, and information retrieval for improving knowledge storage and retrieval. As an example, we discuss how to implement both a user manual and an online help system as one system. The following technologies are combined: a web-based design, a frame-based knowledge engine, use of an advanced full-text search engine, and simple techniques to control terminology. We have combined graphical browsing with several unusual forms of text retrieval,for example, to the sentence and paragraph level. [source]


    A USB kit for digital I/O applications in a digital electronics lab designed by using PIC16C765 microcontroller

    COMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 2 2009
    Ali Buldu
    Abstract In this article, a USB Kit is designed by using Microchip's PIC16C765 microcontroller that has a low-speed USB serial interface engine. It is used to communicate with and/or through USB port for digital I/O applications in a Digital Electronics Lab. In this education kit, two groups of keys (switches) and a group of LED are used to realize the experiments about logic gate applications included in Electronics and Computer Education Department's curriculum of Marmara University and also included in other faculties' curriculums related to the engineering science all around the world. In designed board, one of the key groups is 8-bit software-controlled by using simulator interface and the other is 8-bit user-controlled by using real switches existing on the board. © 2008 Wiley Periodicals, Inc. Comput Appl Eng Educ 17: 131,138, 2009; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae20172 [source]


    Effective page refresh policy

    COMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 3 2007
    Kai Gao
    Abstract Web pages are created or updated randomly. As for a search engine, keeping up with the evolving Web is necessary. But previous studies have shown the crawler's refresh ability is limited because it is not easy to detect the change instantly, especially when the resources are limited. This article concerns modeling on an effective Web page refresh policy and finding the refresh interval with minimum total waiting time. The major concern is how to model the change and which part should be updated more often. Toward this goal, the Poisson process is used to model the process. Further, the relevance is also used to adjust the process, and the probability on some sites is higher than others so these sites will be given more opportunities to be updated. It is essential when the bandwidth is not wide enough or the resource is limited. The experimental results validate the feasibility of the approach. On the basis of the above works, an educational search engine has been developed. © 2007 Wiley Periodicals, Inc. Comput Appl Eng Educ 14: 240,247, 2007; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20155 [source]


    Interactive Web-based package for computer-aided learning of structural behavior

    COMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 3 2002
    X. F. Yuan
    Abstract This paper presents an innovative Web-based package named CALSB for computer-aided learning of structural behavior. The package was designed to be widely accessible through the Internet, user-friendly by the automation of many input functions and the extensive use of cursor movements, and dynamically interactive by linking all input and output data to a single graphical display on the screen. The package includes an analysis engine based on the matrix stiffness method, so the response of any two-dimensional skeletal structure can be predicted and graphically displayed. The package thus provides a virtual laboratory environment in which the user can "build and test" two-dimensional skeletal structures of unlimited choices to enhance his understanding of structural behavior. In addition, the package includes two other innovative features, structural games and paradoxes. The structural games in the package represent perhaps the first attempt at intentionally combining the learning of structural behavior with joy and excitement, while the structural paradoxes provide a stimulating environment conducive for the development of creative problem solving skills of the user. © 2002 Wiley Periodicals, Inc. Comput Appl Eng Educ 10: 121,136, 2002; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.10020 [source]


    Using an Intermediate Skeleton and Inverse Kinematics for Motion Retargeting

    COMPUTER GRAPHICS FORUM, Issue 3 2000
    Jean-Sébastien Monzani
    In this paper, we present a new method for solving the Motion Retargeting Problem, by using an intermediate skeleton. This allows us to convert movements between hierarchically and geometrically different characters. An Inverse Kinematics engine is then used to enforce Cartesian constraints while staying as close as possible to the captured motion. [source]


    The Grid Resource Broker workflow engine

    CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 15 2008
    M. Cafaro
    Abstract Increasingly, complex scientific applications are structured in terms of workflows. These applications are usually computationally and/or data intensive and thus are well suited for execution in grid environments. Distributed, geographically spread computing and storage resources are made available to scientists belonging to virtual organizations sharing resources across multiple administrative domains through established service-level agreements. Grids provide an unprecedented opportunity for distributed workflow execution; indeed, many applications are well beyond the capabilities of a single computer, and partitioning the overall computation on different components whose execution may benefit from runs on different architectures could provide better performances. In this paper we describe the design and implementation of the Grid Resource Broker (GRB) workflow engine. Copyright © 2008 John Wiley & Sons, Ltd. [source]


    Automatic capture and efficient storage of e-Science experiment provenance

    CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 5 2008
    Roger S. Barga
    Abstract For the first provenance challenge, we introduce a layered model to represent workflow provenance that allows navigation from an abstract model of the experiment to instance data collected during a specific experiment run. We outline modest extensions to a commercial workflow engine so it will automatically capture provenance at workflow runtime. We also present an approach to store this provenance data in a relational database. Finally, we demonstrate how core provenance queries in the challenge can be expressed in SQL and discuss the merits of our layered representation. Copyright © 2007 John Wiley & Sons, Ltd. [source]


    Towards workflow simulation in service-oriented architecture: an event-based approach

    CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 4 2008
    Yanchong Zheng
    Abstract The emergence of service-oriented architecture (SOA) has brought about a loosely coupled computing environment that enables flexible integration and reuse of heterogeneous systems. On building a SOA for application systems, more and more research has been focused on service composition, in which workflow and simulation techniques have shown great potential. Simulation of services' interaction is important since the services ecosystem is dynamic and in continuous evolution. However, there is a lack in the research of services' simulation, especially models, methods and systems to support the simulation of interaction behavior of composite services. In this paper, an enhanced workflow simulation method with the support of interactive events mechanism is proposed to fulfill this requirement. At build time, we introduce an event sub-model in the workflow meta-model, and our simulation engine supports the event-based interaction pattern at run time. With an example simulated in the prototype system developed according to our method, the advantages of our method in model verification and QoS evaluation for service compositions are also highlighted. Copyright © 2007 John Wiley & Sons, Ltd. [source]


    Performance analysis of a semantics-enabled service registry

    CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 3 2008
    W. Fang
    Abstract Service discovery is a critical task in service-oriented architectures. In this paper, we study GRIMOIRES, the semantics-enabled service registry of the OMII software distribution, from a performance perspective. We study the scalability of GRIMOIRES against the amount of information that has been published into it. The methodology we use and the data we present are helpful for researchers to understand the performance characteristics of the registry and, more generally, of semantics-enabled service discovery. Based on this experimentation, we claim that GRIMOIRES is an efficient semantics-aware service discovery engine. Copyright © 2007 John Wiley & Sons, Ltd. [source]


    Plug-and-play remote portlet publishing

    CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 12 2007
    X. D. Wang
    Abstract Web Services for Remote Portlets (WSRP) is gaining attention among portal developers and vendors to enable easy development, increased richness in functionality, pluggability, and flexibility of deployment. Whilst currently not supporting all WSRP functionalities, open-source portal frameworks could in future use WSRP Consumers to access remote portlets found from a WSRP Producer registry service. This implies that we need a central registry for the remote portlets and a more expressive WSRP Consumer interface to implement the remote portlet functions. This paper reports on an investigation into a new system architecture, which includes a Web Services repository, registry, and client interface. The Web Services repository holds portlets as remote resource producers. A new data structure for expressing remote portlets is found and published by populating a Universal Description, Discovery and Integration (UDDI) registry. A remote portlet publish and search engine for UDDI has also been developed. Finally, a remote portlet client interface was developed as a Web application. The client interface supports remote portlet features, as well as window status and mode functions. Copyright © 2007 John Wiley & Sons, Ltd. [source]


    The LEAD Portal: a TeraGrid gateway and application service architecture

    CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 6 2007
    Marcus Christie
    Abstract The Linked Environments for Atmospheric Discovery (LEAD) Portal is a science application portal designed to enable effective use of Grid resources in exploring mesoscale meteorological phenomena. The aim of the LEAD Portal is to provide a more productive interface for doing experimental work by the meteorological research community, as well as bringing weather research to a wider class of users, meaning pre-college students in grades 6,12 and undergraduate college students. In this paper, we give an overview of the LEAD project and the role that LEAD portal is playing in reaching its goals. We then describe the various technologies we are using to bring powerful and complex scientific tools to educational and research users. These technologies,a fine-grained capability based authorization framework, an application service factory toolkit, and a Web services-based workflow execution engine and supporting tools,enable our team to deploy these once inaccessible, stovepipe scientific codes onto a Grid where they can be collectively utilized. Copyright © 2006 John Wiley & Sons, Ltd. [source]


    Enabling interactive and collaborative oil reservoir simulations on the Grid

    CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 11 2005
    Manish Parashar
    Abstract Grid-enabled infrastructures and problem-solving environments can significantly increase the scale, cost-effectiveness and utility of scientific simulations, enabling highly accurate simulations that provide in-depth insight into complex phenomena. This paper presents a prototype of such an environment, i.e. an interactive and collaborative problem-solving environment for the formulation, development, deployment and management of oil reservoir and environmental flow simulations in computational Grid environments. The project builds on three independent research efforts: (1) the IPARS oil reservoir and environmental flow simulation framework; (2) the NetSolve Grid engine; and (3) the Discover Grid-based computational collaboratory. Its primary objective is to demonstrate the advantages of an integrated simulation infrastructure towards effectively supporting scientific investigation on the Grid, and to investigate the components and capabilities of such an infrastructure. Copyright © 2005 John Wiley & Sons, Ltd. [source]


    The Role of Effective Modeling in the Development of Self-Efficacy: The Case of the Transparent Engine,

    DECISION SCIENCES JOURNAL OF INNOVATIVE EDUCATION, Issue 1 2007
    Kevin P. Scheibe
    ABSTRACT Computing technology augments learning in education in a number of ways. One particular method uses interactive programs to demonstrate complex concepts. The purpose of this article is to examine one type of interactive learning technology, the transparent engine. The transparent engine allows instructors and students to view and directly interact with educational concepts such as Web-enabled software development. The article first presents a framework describing transparent engines. The framework details four types of transparent engines: (1) enactive mastery/manipulatable, (2) enactive mastery/nonmanipulatable, (3) vicarious experience/manipulatable, and (4) vicarious experience/nonmanipulatable. Following this, we present the results of an experiment designed to examine this framework by testing its predictions for one quadrant, vicarious experience/nonmanipulatable. The results support the framework in that students taught concepts with the aid of the vicarious experience/nonmanipulatable transparent engine had significantly higher domain-specific self-efficacy compared to those taught the same concepts without this tool. [source]


    The Future of Search: A Different Perspective

    DESIGN MANAGEMENT REVIEW, Issue 1 2009
    Stephen P. Anderson Vice President
    The mission at Viewzi is to dramatically improve the search experience. But, as Stephen Anderson explains, that doesn't mean developing a better search engine; rather, it means developing a better way to view search results. The results are a series of custom-tailored scenes whose look and feel change depending on the intent of the search. It's an impressive innovation that promises to reshape the Internet landscape. [source]


    Patient-centred and professional-directed implementation strategies for diabetes guidelines: a cluster-randomized trial-based cost-effectiveness analysis

    DIABETIC MEDICINE, Issue 2 2006
    R. F. Dijkstra
    Abstract Aims Economic evaluations of diabetes interventions do not usually include analyses on effects and cost of implementation strategies. This leads to optimistic cost-effectiveness estimates. This study reports empirical findings on the cost-effectiveness of two implementation strategies compared with usual hospital outpatient care. It includes both patient-related and intervention-related cost. Patients and methods In a clustered-randomized controlled trial design, 13 Dutch general hospitals were randomly assigned to a control group, a professional-directed or a patient-centred implementation programme. Professionals received feedback on baseline data, education and reminders. Patients in the patient-centred group received education and diabetes passports. A validated probabilistic Dutch diabetes model and the UKPDS risk engine are used to compute lifetime disease outcomes and cost in the three groups, including uncertainties. Results Glycated haemoglobin (HbA1c) at 1 year (the measure used to predict diabetes outcome changes over a lifetime) decreased by 0.2% in the professional-change group and by 0.3% in the patient-centred group, while it increased by 0.2% in the control group. Costs of primary implementation were < 5 Euro per head in both groups, but average lifetime costs of improved care and longer life expectancy rose by 9389 Euro and 9620 Euro, respectively. Life expectancy improved by 0.34 and 0.63 years, and quality-adjusted life years (QALY) by 0.29 and 0.59. Accordingly, the incremental cost per QALY was 32 218 Euro for professional-change care and 16 353 for patient-centred care compared with control, and 881 Euro for patient-centred vs. professional-change care. Uncertainties are presented in acceptability curves: above 65 Euro per annum the patient-directed strategy is most likely the optimum choice. Conclusion Both guideline implementation strategies in secondary care are cost-effective compared with current care, by Dutch standards, for these patients. Additional annual costs per patient using patient passports are low. This analysis supports patient involvement in diabetes in the Netherlands, and probably also in other Western European settings. [source]