WorldWideScience

Sample records for aided concurrent engineering

  1. Concurrent engineering

    Science.gov (United States)

    Chamis, C. C.; Leger, L.; Hunter, D.; Jones, C.; Sprague, R.; Berke, L.; Newell, J.; Singhal, S.

    1991-01-01

    The following subject areas are covered: issues (liquid rocket propulsion - current development approach, current certification process, and costs of engineering changes); state of the art (DICE information management system, key government participants, project development strategy, quality management, and numerical propulsion system simulation); needs identified; and proposed program.

  2. Concurrent Software Engineering Project

    Science.gov (United States)

    Stankovic, Nenad; Tillo, Tammam

    2009-01-01

    Concurrent engineering or overlapping activities is a business strategy for schedule compression on large development projects. Design parameters and tasks from every aspect of a product's development process and their interdependencies are overlapped and worked on in parallel. Concurrent engineering suffers from negative effects such as excessive…

  3. Concurrent Engineering Research and Application

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Research and application of Concurrent Engineering have produced good results. A Chinese style concurrent engineering architecture and reference mode has been produced. A series of break thoughts in BPR (Business Process Reengineering) have been made with organization of the IPT (Integrated Product Development Team) and engineering support technologies. Several prototype tools were developed, including product development process modeling and management, QFD-based schema design and decision making, PDM-based concurrent design, STEP-based CAD/CAPP/CAM integration, design for assembly, design for manufacturing, computer aided fixture design, and machining process simulation. Finally, the research results were used in the development of two complex components in an aerospace application, and satisfactory results were obtained.

  4. Concurrent engineering teams. Volume 2: Annotated bibliography

    Science.gov (United States)

    Richter, Karen J.; Dierolf, David A.

    1990-11-01

    Specific concurrent engineering practices vary among organizations. There are, however, various management practices that appear to work well for most organizations. This paper presents the reader with specific, useful examples from several defense contractors illustrating how multifunctional concurrent engineering teams are being organized and managed and how concurrent engineering team meetings are conducted and supported. The types of computer support that could be used to enhance the efficiency and effectiveness of concurrent engineering team meetings are identified. The general findings are that there exists a direct relationship between total quality management (TQM) and concurrent engineering, and that many applications of computer-aided group problem solving are possible and practical today for the concurrent engineering team meetings. Areas identified for additional research are the documentation of the decision process and rationale during the product and process definition, the capturing of lessons learned during the implementation of concurrent engineering, and the performance evaluation and training of team members.

  5. Feature conversion for concurrent engineering

    NARCIS (Netherlands)

    De Kraker, J.K.

    1998-01-01

    Feature conversion for concurrent engineering integrates two modern product development paradigms. Concurrent engineering is a product development paradigm in which multiple engineering disciplines participate. It optimizes a product with respect to available resources and product quality, for which

  6. CONCURRENT ENGINEERING WITH CONSTRAINT NETWORKS

    OpenAIRE

    Steve Minnaar; Robert Reinecke

    2012-01-01

    Concurrent engineering is a systematic approach to the integrated, concurrent design of products and their related processes, including manufacture and support. It allows the consideration of all elements of the product's life cycle, from conception through disposal, including quality, cost, manufacturing, and customer requirements. Constraint networks as an approach to concurrent engineering provides considerable advantages over the conventional approaches to improve engineering. Constraint ...

  7. A review of concurrent engineering

    OpenAIRE

    Juárez Varón, David; Peydro, M. A.; MENGUAL RECUERDA, ANA; Ferrándiz Bou, Santiago

    2015-01-01

    This paper attempts to explain and disaggregate different focuses of concurrent engineering, analyzing their application to product development and highlighting the improvements involved in their enforcement. Improvements can be observed in projects (quality), in scheduling (reducing the duration) and the cost of implementation (savings), basic achievements of concurrent engineering. Companies that already apply concurrent engineering are often multinationals, being the majority group in use....

  8. Feature conversion for concurrent engineering

    OpenAIRE

    Kraker, J.K. de

    1998-01-01

    Feature conversion for concurrent engineering integrates two modern product development paradigms. Concurrent engineering is a product development paradigm in which multiple engineering disciplines participate. It optimizes a product with respect to available resources and product quality, for which it requires to communicate between the different engineering disciplines. Feature conversion is a feature modeling technique. The feature modeling paradigm combines geometric and functional produc...

  9. Concurrent engineering: effective deployment strategies

    OpenAIRE

    Unny Menon; Michael Graham

    1996-01-01

    This paper provides a comprehensive insight into current trends and developments in Concurrent Engineering for integrated development of products and processes with the goal of completing the entire cycle in a shorter time, at lower overall cost and with fewer engineering design changes after product release. The evolution and definition of Concurrent Engineering are addressed first, followed by a concise review of the following elements of the concurrent engineering approach to product devel...

  10. Concurrent engineering research center

    Science.gov (United States)

    Callahan, John R.

    1995-01-01

    The projects undertaken by The Concurrent Engineering Research Center (CERC) at West Virginia University are reported and summarized. CERC's participation in the Department of Defense's Defense Advanced Research Project relating to technology needed to improve the product development process is described, particularly in the area of advanced weapon systems. The efforts committed to improving collaboration among the diverse and distributed health care providers are reported, along with the research activities for NASA in Independent Software Verification and Validation. CERC also takes part in the electronic respirator certification initiated by The National Institute for Occupational Safety and Health, as well as in the efforts to find a solution to the problem of producing environment-friendly end-products for product developers worldwide. The 3M Fiber Metal Matrix Composite Model Factory Program is discussed. CERC technologies, facilities,and personnel-related issues are described, along with its library and technical services and recent publications.

  11. Basic studies on computer aided concurrent engineering for hull structure design and piping design; Kakugi ittai wo koryoshita doji heikotekina sekkei no shien ni kansuru kisoteki kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Aoyama, K.; Sawada, K. [The University of Tokyo, Tokyo (Japan)

    1996-12-31

    Considering integrated hull and piping design in shipbuilding industry as a good example for concurrent engineering (CE), discussions were given on a computer aided method to perform integrated hull and piping design smoothly. When CE aiding by means of a computer is considered, it is important to discuss a method for information management not only for `utilization of product models`, but also for `maintaining consistency between items of product information` and `concurrent utilization and production of product information` in concurrent designs. For the CE aided information management, utilization and production of the product information is effective if restrictive relationship between items of product information, and design functions are made clear. Definitions were given on the restrictive relationship between items of product information and `restrictive relationship information` that has `decision/provisional decision`, `date and time`, `designer` and `design functions`. Furthermore, `comprehensive relationship between items of product information` that can be produced from the restrictive relationship information was defined as a `restrictive network`. Utilizing the restrictive relationship between items of product information for CE aiding is effective. 9 refs., 14 figs.

  12. Concurrent engineering: effective deployment strategies

    Directory of Open Access Journals (Sweden)

    Unny Menon

    1996-12-01

    Full Text Available This paper provides a comprehensive insight into current trends and developments in Concurrent Engineering for integrated development of products and processes with the goal of completing the entire cycle in a shorter time, at lower overall cost and with fewer engineering design changes after product release. The evolution and definition of Concurrent Engineering are addressed first, followed by a concise review of the following elements of the concurrent engineering approach to product development: Concept Development: The Front-End Process, identifying Customer Needs and Quality Function Deployment, Establishing Product Specifications, Concept Selection, Product Architecture, Design for Manufacturing, Effective Rapid Prototyping, and The Economics of Product Development. An outline of a computer-based tutorial developed by the authors and other graduate students funded by NASA ( accessible via the world-wide-web . is provided in this paper. A brief discussion of teamwork for successful concurrent engineering is included, t'ase histories of concurrent engineering implementation at North American and European companies are outlined with references to textbooks authored by Professor Menon and other writers. A comprehensive bibliography on concurrent engineering is included in the paper.

  13. Fuzzy simulation in concurrent engineering

    Science.gov (United States)

    Kraslawski, A.; Nystrom, L.

    1992-01-01

    Concurrent engineering is becoming a very important practice in manufacturing. A problem in concurrent engineering is the uncertainty associated with the values of the input variables and operating conditions. The problem discussed in this paper concerns the simulation of processes where the raw materials and the operational parameters possess fuzzy characteristics. The processing of fuzzy input information is performed by the vertex method and the commercial simulation packages POLYMATH and GEMS. The examples are presented to illustrate the usefulness of the method in the simulation of chemical engineering processes.

  14. CAPP Framework System for Concurrent Engineering

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Difficulty in generalizing and lack of adaptability are important factors that hamper a computer aided process planning (CAPP) system from being popular and practical. New manufacturing philosophies such as Concurrent Engineering require special characteristic of a CAPP system. Proposed in this paper is a CAPP framework system for Concurrent Engineering (CAPPFS-CE) which can meet the requirements of Concurrent Engineering and whose information models, function models and decision logic can be customized by users to form various CAPP application systems. Its function requirements are discussed broadly. An architecture for CAPPFS-CE is presented. It is based on abstract information models (AIMs) and abstract function models (AFMs). The kernel is formed by customization interpretation, internal process control and decision engine. A new information modeling and system development method, information element method (IEM), is introduced to build up AIMs, decision engine, and AFMs and then realize a CAPPFS-CE. THCAPP-SHELL, a CAPPFS-CE developed by IEM, is demonstrated. A CAPP system produced by customizing THCAPP-SHELL for complex structural parts in a concurrent engineering environment is shown.

  15. A Reactive Object Model for Concurrent Engineering Design

    OpenAIRE

    Nguyen, Toan

    1995-01-01

    A reactive object model is defined to control the design process of evolving objects in concurrent engineering environments. The goal is to support engineers in controlling the result of their design decisions, using a software automaton as a plug-in addition to computer-aided design platforms that support concurrent engineering. The automaton implements a reactive design specification for composite objects with multiple representations, that includes a model for their design process. The syn...

  16. Integration-based cooperation in concurrent engineering

    OpenAIRE

    Hillebrand, Gerd; Krakowski, Patricia; Lockemann, Peter C.; Posselt, Dietmar

    1998-01-01

    Motivated by global competition, rapid technological advance and shorter product life cycles, enterprises tend to restructure the traditionally sequential product development process into a collaborative, concurrent, and iterative effort called Concurrent Engineering. In Concurrent Engineering, design phases overlap and potentially incomplete results are exchanged between phases, facilitating early initiation of later stages and quick corrective feedback. ...

  17. Implementation of a generic concurrent engineering environment framework for boatbuilding

    OpenAIRE

    Sobey, A.J.; Blake, J.I.R.; Shenoi, R.A.

    2013-01-01

    Boatbuilding is a growth market with global competition and tight profit margins. Concurrent engineering is not presently prevalent within the boatbuilding industry and yet this is a technique that has found much success in other industries. A methodology has, therefore, been developed to aid design in the leisure boatbuilding industry. This environment uses collaborative engineering and automated communication to aid the passing of direct communication between all members of the design team....

  18. A Reference Framework for Concurrent Engineering

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Considering the diversity of methods and tools offered to concurrent engineering, the aspects playing important roles in the concurrent engineering c ontext have been pinpointed as being four core elements which are Activity, Meth od, Object and Information. Based on these four elements, a reference framework called AMOI is proposed to be the guideline for the systematic concurrent produc t design. Using the AMOI reference framework, concurrent product development sys tem can be structured into four function models (including the activity model, m ethod model, object model and information model) which are interconnected with e ach other.

  19. A Continuous Verification Process in Concurrent Engineering

    OpenAIRE

    Schaus, Volker; Tiede, Michael; Fischer, Philipp M.; Lüdtke, Daniel; Gerndt, Andreas

    2013-01-01

    This paper presents how a continuous mission verification process similar than in software engineering can be applied in early spacecraft design and Concurrent Engineering. Following the Model-based Systems Engineering paradigm, all engineers contribute to one single centralized data model of the system. The data model is enriched with some extra information to create an executable representation of the spacecraft and its mission. That executable scenario allows for verifications agains...

  20. Incorporating concurrent engineering and design economics in a decision support system

    OpenAIRE

    Lee, Pui Mun

    1993-01-01

    Concurrent engineering is a philosophy for improving design communication and aiding the process of recognizing and resolving design conflicts. Design economics is an integrated part of the concurrent engineering process, since cost-effective product design is at the root of many design conflicts. However, the bulk of research on concurrent engineering focuses on deriving better methods for coordinating both product and process designs with respect to functionality and manufact...

  1. Characterizing Distributed Concurrent Engineering Teams: A Descriptive Framework for Aerospace Concurrent Engineering Design Teams

    Science.gov (United States)

    Chattopadhyay, Debarati; Hihn, Jairus; Warfield, Keith

    2011-01-01

    As aerospace missions grow larger and more technically complex in the face of ever tighter budgets, it will become increasingly important to use concurrent engineering methods in the development of early conceptual designs because of their ability to facilitate rapid assessments and trades in a cost-efficient manner. To successfully accomplish these complex missions with limited funding, it is also essential to effectively leverage the strengths of individuals and teams across government, industry, academia, and international agencies by increased cooperation between organizations. As a result, the existing concurrent engineering teams will need to increasingly engage in distributed collaborative concurrent design. This paper is an extension of a recent white paper written by the Concurrent Engineering Working Group, which details the unique challenges of distributed collaborative concurrent engineering. This paper includes a short history of aerospace concurrent engineering, and defines the terms 'concurrent', 'collaborative' and 'distributed' in the context of aerospace concurrent engineering. In addition, a model for the levels of complexity of concurrent engineering teams is presented to provide a way to conceptualize information and data flow within these types of teams.

  2. An Example of Concurrent Engineering

    Science.gov (United States)

    Rowe, Sidney; Whitten, David; Cloyd, Richard; Coppens, Chris; Rodriguez, Pedro

    1998-01-01

    The Collaborative Engineering Design and Analysis Room (CEDAR) facility allows on-the- spot design review capability for any project during all phases of development. The required disciplines assemble in this facility to work on any problems (analysis, manufacturing, inspection, etc.) associated with a particular design. A small highly focused team of specialists can meet in this room to better expedite the process of developing a solution to an engineering task within the framework of the constraints that are unique to each discipline. This facility provides the engineering tools and translators to develop a concept within the confines of the room or with remote team members that could access the team's data from other locations. The CEDAR area is envisioned as excellent for failure investigation meetings to be conducted where the computer capabilities can be utilized in conjunction with the Smart Board display to develop failure trees, brainstorm failure modes, and evaluate possible solutions.

  3. Concurrent Engineering in seafood product development

    DEFF Research Database (Denmark)

    Jonsdottir, Stella; Vesterager, Johan; Børresen, Torger

    1998-01-01

    Concurrent Engineering (CE) can provide an improved approach to product development for extending the lines of seafood products. Information technology support tools based on product models can provide an integrated and simultaneous approach for specifying new recipes. The seafood industry can...... techniques. it is anticipated that other food industries also can benefit from the more simultaneous approach...

  4. Concurrent Engineering Design Using Intelligent Agents.

    Science.gov (United States)

    Parkinson, Brian

    1998-01-01

    Describes Design Builder, interactive multimedia software that was developed to enable undergraduate engineers to experience working in a concurrent environment without direct and specialized teaching-staff support, and to provide an interactive and intelligent simulation environment from which users may develop a culture that introduces…

  5. Concurrent Engineering in the 21st Century

    NARCIS (Netherlands)

    Stjepandic, Josip; Wognum, P.M.; Verhagen, Wim

    2015-01-01

    Presenting the gradual evolution of the concept of Concurrent Engineering (CE), and the technical, social methods and tools that have been developed, including the many theoretical and practical challenges that still exist, this book serves to summarize the achievements and current challenges of CE

  6. Computer aided engineering drawing

    CERN Document Server

    Dubey, N H

    2006-01-01

    This book caters to the need of First Year Engineering Students desiring to achieve a firm footage in the Subject Computer Aided Engineering Drawing. The formulation and methodology of the contents in this book is that one can easily understand the finer details of the subject and can master them with regular practice. It is essential that every on involved in engineering field must understand CAD for Drawing. This book contains well-illustrated figures along with theory for explaining procedures wherever necessary. A large number of solved and unsolved problems are provided so that one can ge

  7. Implementation of a Three-Semester Concurrent Engineering Design Sequence for Lower-Division Engineering Students

    Science.gov (United States)

    Bertozzi, N.; Hebert, C.; Rought, J.; Staniunas, C.

    2007-01-01

    Over the past decade the software products available for solid modeling, dynamic, stress, thermal, and flow analysis, and computer-aiding manufacturing (CAM) have become more powerful, affordable, and easier to use. At the same time it has become increasingly important for students to gain concurrent engineering design and systems integration…

  8. Concurrent engineering applied to key industrial sectors

    OpenAIRE

    Juárez Varón, David; Segui Llinares, Vicente Jesús; MENGUAL RECUERDA, ANA; Ferrándiz Bou, Santiago

    2015-01-01

    The use of advanced techniques in work, such as concurrent engineering, on the development of projects implies that all areas involved participate from the start of the primary phases. Getting a correct product is the main target, with an estimated term and controlled and reduced costs. Working with a complex product within a context in design and manufacturing in a company in a highly competitive market, involves the problem domain as a key issue. In this paper, the development of concurren...

  9. Computer aided control engineering

    DEFF Research Database (Denmark)

    Szymkat, Maciej; Ravn, Ole

    1997-01-01

    Current developments in the field of Computer Aided Control Engineering (CACE) have a visible impact on the design methodologies and the structure of the software tools supporting them. Today control engineers has at their disposal libraries, packages or programming environments that may...... in CACE enhancing efficient flow of information between the tools supporting the following phases of the design process. In principle, this flow has to be two-way, and more or less automated, in order to enable the engineer to observe the propagation of the particular design decisions taken at various...... levels.The major conclusions of the paper are related with identifying the factors affecting the software tool integration in a way needed to facilitate design "inter-phase" communication. These are: standard application interfaces, dynamic data exchange mechanisms, code generation techniques and general...

  10. The Importance of CAD and Knowledge Management in Concurrent Engineering Project Performance

    OpenAIRE

    Poh Kiat Ng; Gerald Guan Gan Goh; Uchenna Cyril Eze

    2011-01-01

    As a complex method for manufacturing and development, concurrent engineering has been studied and implemented extensively in the manufacturing industry to speed up production schedules and to reduce costs. One of the tools used in concurrent engineering is computer-aided design or CAD in short. CAD applications in multifunctional knowledge distribution refer to the use of CAD to provide information to different groups of employees in their organisation to sustain new product development acti...

  11. Concurrent Engineering Working Group White Paper Distributed Collaborative Design: The Next Step in Aerospace Concurrent Engineering

    Science.gov (United States)

    Hihn, Jairus; Chattopadhyay, Debarati; Karpati, Gabriel; McGuire, Melissa; Panek, John; Warfield, Keith; Borden, Chester

    2011-01-01

    As aerospace missions grow larger and more technically complex in the face of ever tighter budgets, it will become increasingly important to use concurrent engineering methods in the development of early conceptual designs because of their ability to facilitate rapid assessments and trades of performance, cost and schedule. To successfully accomplish these complex missions with limited funding, it is essential to effectively leverage the strengths of individuals and teams across government, industry, academia, and international agencies by increased cooperation between organizations. As a result, the existing concurrent engineering teams will need to increasingly engage in distributed collaborative concurrent design. The purpose of this white paper is to identify a near-term vision for the future of distributed collaborative concurrent engineering design for aerospace missions as well as discuss the challenges to achieving that vision. The white paper also documents the advantages of creating a working group to investigate how to engage the expertise of different teams in joint design sessions while enabling organizations to maintain their organizations competitive advantage.

  12. Engineering Bereitschaft as an enabler for Concurrent Engineering

    DEFF Research Database (Denmark)

    Christiansen, Kåre; Vesterager, Johan

    1999-01-01

    Industrial companies observe a general trend towards more customised products and shorter product life cycles. Furthermore, the market demands shorter lead-time and high-quality products at a competitive price. Concurrent Engineering address these challenges. Product modelling is a key aspect...... in that way be done within a week. Such a fast cycle time allows for multiple iterations in search of a "good" design.The Bereitschaft idea requires efficient modelling methods. Modelling methods are well described in literature but the general assumption is that software engineers should drive modelling...

  13. Model-Based Systems Engineering in Concurrent Engineering Centers

    Science.gov (United States)

    Iwata, Curtis; Infeld, Samatha; Bracken, Jennifer Medlin; McGuire, Melissa; McQuirk, Christina; Kisdi, Aron; Murphy, Jonathan; Cole, Bjorn; Zarifian, Pezhman

    2015-01-01

    Concurrent Engineering Centers (CECs) are specialized facilities with a goal of generating and maturing engineering designs by enabling rapid design iterations. This is accomplished by co-locating a team of experts (either physically or virtually) in a room with a narrow design goal and a limited timeline of a week or less. The systems engineer uses a model of the system to capture the relevant interfaces and manage the overall architecture. A single model that integrates other design information and modeling allows the entire team to visualize the concurrent activity and identify conflicts more efficiently, potentially resulting in a systems model that will continue to be used throughout the project lifecycle. Performing systems engineering using such a system model is the definition of model-based systems engineering (MBSE); therefore, CECs evolving their approach to incorporate advances in MBSE are more successful in reducing time and cost needed to meet study goals. This paper surveys space mission CECs that are in the middle of this evolution, and the authors share their experiences in order to promote discussion within the community.

  14. Lessons Learned from One-Week Concurrent Engineering Study Approach

    OpenAIRE

    Braukhane, Andy; Romberg, Oliver

    2011-01-01

    The present paper discusses the advantages and disadvantages of the one-week Concurrent Engineering (CE) study approach applied currently in the Concurrent Engineering Faciliry (CEF) at DLR which has been operating since early 2009. Up to now, ca. 20 condensed studies have been performed at the DLR CEF. This paper compares this approach to the more stretched process, applied e. g. at ESA ESTEC’s Concurrent Design Facility (CDF). The investigation takes into account the different space systems...

  15. CONCURRENT PRODUCTION ENGINEERING SYSTEM FOR BUFFER SIZE AND FLEXIBLE TRANSFER LINE LAYOUT DESIGN

    Institute of Scientific and Technical Information of China (English)

    Hidehiko YAMAMOTO; Jaber ABU QUDEIRI; M. Anouar JAMALI

    2008-01-01

    In this paper we propose a Concurrent Production Engineering System (COPES) for the flexible transfer line (FTL) layout design in a restricted area. COPES first determines the buffer size in front of the bay of each machine tool in the FTL and then initializes a computer aided design (CAD) system to draw the FTL in a restricted area. We develop a set of modules systems which have been integrated into a single framework, in accordance with the practice of concurrent engineering. Concurrent engineering involves the cooperation of these activities. It's expected that the developed COPES can improve the cooperation between production engineers' and the plant designer. This can be done by enabling the production engineers' to make better decision regarding FTL buffer size.

  16. Probabilistic simulation of concurrent engineering of propulsion systems

    Science.gov (United States)

    Chamis, C. C.; Singhal, S. N.

    1993-01-01

    Technology readiness and the available infrastructure is assessed for timely computational simulation of concurrent engineering for propulsion systems. Results for initial coupled multidisciplinary, fabrication-process, and system simulators are presented including uncertainties inherent in various facets of engineering processes. An approach is outlined for computationally formalizing the concurrent engineering process from cradle-to-grave via discipline dedicated workstations linked with a common database.

  17. Computational simulation of concurrent engineering for aerospace propulsion systems

    Science.gov (United States)

    Chamis, C. C.; Singhal, S. N.

    1992-01-01

    Results are summarized of an investigation to assess the infrastructure available and the technology readiness in order to develop computational simulation methods/software for concurrent engineering. These results demonstrate that development of computational simulations methods for concurrent engineering is timely. Extensive infrastructure, in terms of multi-discipline simulation, component-specific simulation, system simulators, fabrication process simulation, and simulation of uncertainties - fundamental in developing such methods, is available. An approach is recommended which can be used to develop computational simulation methods for concurrent engineering for propulsion systems and systems in general. Benefits and facets needing early attention in the development are outlined.

  18. Computational simulation for concurrent engineering of aerospace propulsion systems

    Science.gov (United States)

    Chamis, C. C.; Singhal, S. N.

    1993-01-01

    Results are summarized for an investigation to assess the infrastructure available and the technology readiness in order to develop computational simulation methods/software for concurrent engineering. These results demonstrate that development of computational simulation methods for concurrent engineering is timely. Extensive infrastructure, in terms of multi-discipline simulation, component-specific simulation, system simulators, fabrication process simulation, and simulation of uncertainties--fundamental to develop such methods, is available. An approach is recommended which can be used to develop computational simulation methods for concurrent engineering of propulsion systems and systems in general. Benefits and issues needing early attention in the development are outlined.

  19. Dynamic systems-engineering process - The application of concurrent engineering

    Science.gov (United States)

    Wiskerchen, Michael J.; Pittman, R. Bruce

    1989-01-01

    A system engineering methodology is described which enables users, particulary NASA and DOD, to accommodate changing needs; incorporate emerging technologies; identify, quantify, and manage system risks; manage evolving functional requirements; track the changing environment; and reduce system life-cycle costs. The approach is a concurrent, dynamic one which starts by constructing a performance model defining the required system functions and the interrelationships. A detailed probabilistic risk assessment of the system elements and their interrelationships is performed, and quantitative analysis of the reliability and maintainability of an engineering system allows its different technical and process failure modes to be identified and their probabilities to be computed. Decision makers can choose technical solutions that maximize an objective function and minimize the probability of failure under resource constraints.

  20. Computer aided photographic engineering

    Science.gov (United States)

    Hixson, Jeffrey A.; Rieckhoff, Tom

    1988-01-01

    High speed photography is an excellent source of engineering data but only provides a two-dimensional representation of a three-dimensional event. Multiple cameras can be used to provide data for the third dimension but camera locations are not always available. A solution to this problem is to overlay three-dimensional CAD/CAM models of the hardware being tested onto a film or photographic image, allowing the engineer to measure surface distances, relative motions between components, and surface variations.

  1. Engineering Concurrent Software Guided by Statistical Performance Analysis

    NARCIS (Netherlands)

    C. Grelck; K. Hammond; H. Hertlein; P. Hölzenspies; C. Jesshope; R. Kirner; B. Scheuermann; A. Shafarenko; I. te Boekhorst; V. Wieser

    2011-01-01

    This paper introduces the ADVANCE approach to engineering concurrent systems using a new component-based approach. A cost-directed tool-chain maps concurrent programs onto emerging hardware architectures, where costs are expressed in terms of programmer annotations for the throughput, latency and ji

  2. Concurrent Engineering: An Overview Regarding Major Features And Tools

    OpenAIRE

    Dourado, João Paulo; Silva, Rui; Silva, Angela

    2011-01-01

    Concurrent engineering is a methodology of work based on the parallelization of tasks - that means, to perform tasks concurrently. It refers to the approach used in product development in which the functions of design engineering, manufacturing and others, are integrated to reduce the total time required to bring a new product to market. It interacts with all elements of the product life cycle, from conception to disposal, including quality, cost, schedule and customer requirements. Th e conc...

  3. DFM/CAPP/CAM System in a Concurrent Engineering Environment

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    In this paper the importance of DFM/CAPP/CAM system in Concurrent Engineering (CE) is discussed. Based on the analyses of the character of concurrent product design and manufacturing process design, the workflow of DFM/CAPP/CAM system in CE is given. DFM/CAPP/CAM theories, methods and functions are investigated in a delicate and all-round way, and are implemented in the developed DFM/CAPP/CAM system.

  4. Concurrent engineering: Spacecraft and mission operations system design

    Science.gov (United States)

    Landshof, J. A.; Harvey, R. J.; Marshall, M. H.

    1994-01-01

    Despite our awareness of the mission design process, spacecraft historically have been designed and developed by one team and then turned over as a system to the Mission Operations organization to operate on-orbit. By applying concurrent engineering techniques and envisioning operability as an essential characteristic of spacecraft design, tradeoffs can be made in the overall mission design to minimize mission lifetime cost. Lessons learned from previous spacecraft missions will be described, as well as the implementation of concurrent mission operations and spacecraft engineering for the Near Earth Asteroid Rendezvous (NEAR) program.

  5. Concurrent engineering and product models in seafood companies

    DEFF Research Database (Denmark)

    Jonsdottir, Stella; Vesterager, Johan; Børresen, Torger

    1998-01-01

    Concurrent Engineering (CE) can provide an improved approach to product development for extending the lines of seafood products. Information technology (IT) support tools based on product models can provide an integrated and simultaneous approach for specifying new recipes. The seafood industry can...

  6. Improving Construction Process through Integration and Concurrent Engineering

    OpenAIRE

    Malik Khalfan; Naveed Raja

    2012-01-01

    In an increasingly competitive business environment, improvedtime-to-market, reduced production cost, quality of the productand customer involvement are rapidly becoming the key successfactors for any product development process. Consequently, mostorganisations are moving towards the adoption of latest technologyand new management concepts and philosophies such as totalquality management and concurrent engineering (CE) to bringimprovement in their product development process. This paperdiscus...

  7. The engineering of concurrent simulations of complex systems

    OpenAIRE

    Polack, Fiona A.C.; Andrews, Paul S.; Sampson, Adam T

    2009-01-01

    Concurrent process-oriented programming is a natural medium for simulating complex systems, particularly systems where many simple components interact in an environment (which may itself be complex). There is little guidance for engineering complex systems simulation. In the context of simulation work to support immunological research, we explore relevant approaches to modelling, and draw on concepts from dependable and high-integrity systems engineering, including the emphasis on the need to...

  8. Sočasno inženirstvo v teoriji in praksi: Concurrent engineering in theory and practice:

    OpenAIRE

    Kopač, Janez

    2003-01-01

    This paper focuses on the main strategies, principles, processes, practices, technologies and people related to concurrent engineering (CE). In this way itdescribes the major CE organizing factors, tools, methodologies, computer-aided analysis and prototyping. The common approach to product development, still used by many manufacturing companies, is based on the sequential principle and is being replaced by the contemporary concurrent approach. To achieve the best results all key cross-functi...

  9. Risk Identification and Visualization in a Concurrent Engineering Team Environment

    Science.gov (United States)

    Hihn, Jairus; Chattopadhyay, Debarati; Shishko, Robert

    2010-01-01

    Incorporating risk assessment into the dynamic environment of a concurrent engineering team requires rapid response and adaptation. Generating consistent risk lists with inputs from all the relevant subsystems and presenting the results clearly to the stakeholders in a concurrent engineering environment is difficult because of the speed with which decisions are made. In this paper we describe the various approaches and techniques that have been explored for the point designs of JPL's Team X and the Trade Space Studies of the Rapid Mission Architecture Team. The paper will also focus on the issues of the misuse of categorical and ordinal data that keep arising within current engineering risk approaches and also in the applied risk literature.

  10. Concurrent Engineering Oriented CAx/DFx Information Integration

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The information integration, especially in CAD/CAPP/CAM, is a basis for realizing the integrated and concurrent product development in Concurrent Engineering (CE) environment. The integration technology based on STEP application protocol gives an effective way for the CAx/DFx information integration. This paper discusses the characteristics of concurrent product development, analyzes the methodology and technology of STEP, proposes an information integration approach based on STEP AP214, and presents the strategy of product data integration and an integration system implementation architecture. The integration technology based on STEP application protocol and the ST-Developer tools is realized in a prototype system to support product data integration between CAD and its follow-up systems through STEP physical file and STEP information exchange interface.

  11. Application of concurrent engineering in product and process design

    OpenAIRE

    Juárez Varón, David; Segui Llinares, Vicente Jesús; MENGUAL RECUERDA, ANA; Ferrándiz Bou, Santiago

    2015-01-01

    Traditional methods applied to the development of new products are becoming obsolete, being necessary advanced methods based on a new approach that allows work cooperatively. This is called Concurrent Engineering and this paper intends to carry out a review of the integration of this discipline in the new ways of working. The main objective of the new forms of work is to systematize the design by interdisciplinary teams simultaneously working the products, the processes, getting the right des...

  12. Confrontation of viewpoints in a concurrent engineering process

    OpenAIRE

    Martin, Géraldine; Détienne, Françoise; Lavigne, Elisabeth

    2002-01-01

    We present an empirical study aimed at analysing the use of viewpoints in an industrial Concurrent Engineering context. Our focus is on the viewpoints expressed in the argumentative process taking place in evaluation meetings. Our results show that arguments enabling a viewpoint or proposal to be defended are often characterized by the use of constraints. One result involved the way in which the proposals for solutions are assessed during these meetings. We have revealed the existence of spec...

  13. GLobal Integrated Design Environment (GLIDE): A Concurrent Engineering Application

    Science.gov (United States)

    McGuire, Melissa L.; Kunkel, Matthew R.; Smith, David A.

    2010-01-01

    The GLobal Integrated Design Environment (GLIDE) is a client-server software application purpose-built to mitigate issues associated with real time data sharing in concurrent engineering environments and to facilitate discipline-to-discipline interaction between multiple engineers and researchers. GLIDE is implemented in multiple programming languages utilizing standardized web protocols to enable secure parameter data sharing between engineers and researchers across the Internet in closed and/or widely distributed working environments. A well defined, HyperText Transfer Protocol (HTTP) based Application Programming Interface (API) to the GLIDE client/server environment enables users to interact with GLIDE, and each other, within common and familiar tools. One such common tool, Microsoft Excel (Microsoft Corporation), paired with its add-in API for GLIDE, is discussed in this paper. The top-level examples given demonstrate how this interface improves the efficiency of the design process of a concurrent engineering study while reducing potential errors associated with manually sharing information between study participants.

  14. Computer Aided Battery Engineering Consortium

    Energy Technology Data Exchange (ETDEWEB)

    Pesaran, Ahmad

    2016-06-07

    A multi-national lab collaborative team was assembled that includes experts from academia and industry to enhance recently developed Computer-Aided Battery Engineering for Electric Drive Vehicles (CAEBAT)-II battery crush modeling tools and to develop microstructure models for electrode design - both computationally efficient. Task 1. The new Multi-Scale Multi-Domain model framework (GH-MSMD) provides 100x to 1,000x computation speed-up in battery electrochemical/thermal simulation while retaining modularity of particles and electrode-, cell-, and pack-level domains. The increased speed enables direct use of the full model in parameter identification. Task 2. Mechanical-electrochemical-thermal (MECT) models for mechanical abuse simulation were simultaneously coupled, enabling simultaneous modeling of electrochemical reactions during the short circuit, when necessary. The interactions between mechanical failure and battery cell performance were studied, and the flexibility of the model for various batteries structures and loading conditions was improved. Model validation is ongoing to compare with test data from Sandia National Laboratories. The ABDT tool was established in ANSYS. Task 3. Microstructural modeling was conducted to enhance next-generation electrode designs. This 3- year project will validate models for a variety of electrodes, complementing Advanced Battery Research programs. Prototype tools have been developed for electrochemical simulation and geometric reconstruction.

  15. Pulmonary Alveolar Proteinosis in an AIDS Patient without Concurrent Pulmonary Infection

    OpenAIRE

    Liu, Allen T; Miedzinski, Lil J.; Eric Vallieres; Rayner, David C; Lien, Dale C

    1995-01-01

    Patients with acquired immunodeficiency syndrome (AIDS) are potentially at increased risk for developing secondary pulmonary alveolar proteinosis because of underlying immunosuppression and frequent opportunistic lung infections. This condition. however, has been diagnosed uncommonly in these patients and, with the exception of one previously reported case. only in the presence of concurrent pulmonary infection. The case of a 35-year-old male with AIDS who was found on open lung biopsy to hav...

  16. Knowledge Management tools integration within DLR's concurrent engineering facility

    Science.gov (United States)

    Lopez, R. P.; Soragavi, G.; Deshmukh, M.; Ludtke, D.

    The complexity of space endeavors has increased the need for Knowledge Management (KM) tools. The concept of KM involves not only the electronic storage of knowledge, but also the process of making this knowledge available, reusable and traceable. Establishing a KM concept within the Concurrent Engineering Facility (CEF) has been a research topic of the German Aerospace Centre (DLR). This paper presents the current KM tools of the CEF: the Software Platform for Organizing and Capturing Knowledge (S.P.O.C.K.), the data model Virtual Satellite (VirSat), and the Simulation Model Library (SimMoLib), and how their usage improved the Concurrent Engineering (CE) process. This paper also exposes the lessons learned from the introduction of KM practices into the CEF and elaborates a roadmap for the further development of KM in CE activities at DLR. The results of the application of the Knowledge Management tools have shown the potential of merging the three software platforms with their functionalities, as the next step towards the fully integration of KM practices into the CE process. VirSat will stay as the main software platform used within a CE study, and S.P.O.C.K. and SimMoLib will be integrated into VirSat. These tools will support the data model as a reference and documentation source, and as an access to simulation and calculation models. The use of KM tools in the CEF aims to become a basic practice during the CE process. The settlement of this practice will result in a much more extended knowledge and experience exchange within the Concurrent Engineering environment and, consequently, the outcome of the studies will comprise higher quality in the design of space systems.

  17. CAESY - COMPUTER AIDED ENGINEERING SYSTEM

    Science.gov (United States)

    Wette, M. R.

    1994-01-01

    Many developers of software and algorithms for control system design have recognized that current tools have limits in both flexibility and efficiency. Many forces drive the development of new tools including the desire to make complex system modeling design and analysis easier and the need for quicker turnaround time in analysis and design. Other considerations include the desire to make use of advanced computer architectures to help in control system design, adopt new methodologies in control, and integrate design processes (e.g., structure, control, optics). CAESY was developed to provide a means to evaluate methods for dealing with user needs in computer-aided control system design. It is an interpreter for performing engineering calculations and incorporates features of both Ada and MATLAB. It is designed to be reasonably flexible and powerful. CAESY includes internally defined functions and procedures, as well as user defined ones. Support for matrix calculations is provided in the same manner as MATLAB. However, the development of CAESY is a research project, and while it provides some features which are not found in commercially sold tools, it does not exhibit the robustness that many commercially developed tools provide. CAESY is written in C-language for use on Sun4 series computers running SunOS 4.1.1 and later. The program is designed to optionally use the LAPACK math library. The LAPACK math routines are available through anonymous ftp from research.att.com. CAESY requires 4Mb of RAM for execution. The standard distribution medium is a .25 inch streaming magnetic tape cartridge (QIC-24) in UNIX tar format. CAESY was developed in 1993 and is a copyrighted work with all copyright vested in NASA.

  18. Numerical Simulation System for Casting Process in Concurrent Engineering

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    According to the implementing principle and application background of the Concurrent Engineering (CE) project, studies on the integration of numerical simulation system for casting process with CE, simulation of turbulent phenomena in filling process of casting by Algebraic Stress Model (ASM), computation efficiency of filling process and quantitative prediction of shrinkage cavity and porosity under feeding condition of several risers are discussed. After the simulation of casting process of typical magnesium-based alloy casting with complicated structure, remarkable success in assuring the quality is also presented.

  19. Case-based Reasoning in Conflict Negotiation in Concurrent Engineering

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Case-based reasoning (CBR) is a kind of analogous reasoning that is widely used in artificial intelligence. Conflicts are pervasive in Concurrent Engineering design environment. Conflict negotiation is necessary when conflicts occur. It is difficult to resolve conflicts due to several reasons. An approach to resolving conflicts by case-based reasoning is proposed in this paper. The knowledge representation of conflict negotiation cases, the judgment of case similarity, the retrieval model of cases, the management of case bases, and the process of case-based conflict negotiation are studied. The implementation structure of the Case-based Conflict Solving System (CCSS) is also given.

  20. Concurrent Systems Engineering in Aerospace: From Excel-based to Model Driven Design

    OpenAIRE

    Schumann, Holger; Wendel, Heinrich; Braukhane, Andy; Berres, Axel; Gerndt, Andreas; Schreiber, Andreas

    2010-01-01

    Concurrent engineering is a modern and very effective discipline of systems engineering. In the European space domain, the European Space Agency is the pioneer in this area and has performed early design studies for 10 years now. The Integrated Design Model (IDM) is still the state of the art in concurrent engineering software environments. It is based on Microsoft Excel, which induces several benefits and drawbacks related to concurrent engineering. The German Aerospace Center has used t...

  1. Cross Functional Working and Concurrent Engineering – a UK Study

    Directory of Open Access Journals (Sweden)

    H. Williams

    2000-01-01

    Full Text Available This paper reports on the preliminary results of an investigative study into the implementation of concurrent engineering applied to new product development. Concurrent (or Simultaneous engineering is the term commonly given to creating new products using multi-disciplined teams of marketing, design, manufacturing and support functions together with supplier and customers. Such techniques have produced robust, low cost quality products in short concept to market times compared to traditional ones. The research investigated design management practice and performance in a number of organisations across a range of industrial sectors in the UK by means of a questionnaire survey. The results identify the current use of a variety of design practices and methodologies such as different organisational structures, the extent of cross-functional working, the use of design and phase reviews and the use of different technologies. They indicate that companies implementing CE are more successful in time to market performance than those who don’t implement CE. Factors most influencing the successful adoption of CE are design and phase reviews, and, to a lesser extent, the use of multifunctional teams and supplier partnerships.

  2. Concurrent engineering and DFMA approaches on the development of automotive panels and doors

    Directory of Open Access Journals (Sweden)

    F.Z. Krumenauer

    2008-12-01

    Full Text Available Purpose: The automotive industry, in countries such as Brazil, China and India, in contrast to the NorthAmerican and European markets, is in full expansion. Due to the huge competition in the globalized automotivemarket, such countries face a challenge to continue this expansion. Especially important in order to win thisbattle, will be their capacities to release new products in the market faster than their competitors and with morecost efficiency, making an appropriate use of tools such as total quality management, concurrent engineeringand increasing the use of innovative concepts in production and logistics [1,2].Design/methodology/approach: According with the expose above, the aim of this work was to developDFMA tools for an industrial real case. There several tools that could be included in the Design for Excellence(DFX methodologies. Initially, two of those can be outstand here: Design For Manufacturing (DFMand Design For Asse.Findings: In terms of the press shop facilities of the plant the main results, were: layout optimization, press lineautomation feasibility, reduced setup and increased productivity, improved racks logistic, reduced overhead,reduced stamped part scraps and resources with mechanical presses selling. In terms of the planning activities,the main results were: reduce time to market, reduce press shop machinery and die stamping investments andreduce indirect cost.Practical implications: The main proposal of concurrent engineering is to shorten a product development timethrough a simultaneous time implementation of the several stages of the engineering activity in parallel andunder a concurrent mode offering all information required by all elements of the product life cycle.Originality/value: This paper reviews fundamental concepts in concurrent engineering and DFX aiming todiscuss criteria of assembly and manufacturability regarding the development of automotive panels and doors.A more detailed presentation of the Finite

  3. True Concurrent Thermal Engineering Integrating CAD Model Building with Finite Element and Finite Difference Methods

    Science.gov (United States)

    Panczak, Tim; Ring, Steve; Welch, Mark

    1999-01-01

    Thermal engineering has long been left out of the concurrent engineering environment dominated by CAD (computer aided design) and FEM (finite element method) software. Current tools attempt to force the thermal design process into an environment primarily created to support structural analysis, which results in inappropriate thermal models. As a result, many thermal engineers either build models "by hand" or use geometric user interfaces that are separate from and have little useful connection, if any, to CAD and FEM systems. This paper describes the development of a new thermal design environment called the Thermal Desktop. This system, while fully integrated into a neutral, low cost CAD system, and which utilizes both FEM and FD methods, does not compromise the needs of the thermal engineer. Rather, the features needed for concurrent thermal analysis are specifically addressed by combining traditional parametric surface based radiation and FD based conduction modeling with CAD and FEM methods. The use of flexible and familiar temperature solvers such as SINDA/FLUINT (Systems Improved Numerical Differencing Analyzer/Fluid Integrator) is retained.

  4. Concurrent Engineering Approaches for Sustainable Product Development in a Multi-Disciplinary Environment : Proceedings of the 19th ISPE International Conference on Concurrent Engineering

    CERN Document Server

    Rock, Georg; Bil, Cees

    2013-01-01

    The CE Conference series is organized annually by the International Society for Productivity Enhancement (ISPE) and constitutes an important forum for international scientific exchange on concurrent and collaborative enterprise engineering. These international conferences attract a significant number of researchers, industrialists and students, as well as government representatives, who are interested in the recent advances in concurrent engineering research and applications. Concurrent Engineering Approaches for Sustainable Product Development in a Multi-Disciplinary Environment: Proceedings of the 19th ISPE International Conference on Concurrent Engineering contains papers accepted, peer reviewed and presented at the annual conference held  at the University of Applied Sciences in Trier, Germany, from 3rd-7th of September 2012. This covers a wide range of cutting-edge topics including: •Systems Engineering and Innovation •Design for Sustainability •Knowledge Engineering and Management •Managing pro...

  5. Resource Management and Contingencies in Aerospace Concurrent Engineering

    Science.gov (United States)

    Karpati, Gabe; Hyde, Tupper; Peabody, Hume; Garrison, Matthew

    2012-01-01

    significant concern in designing complex systems implementing new technologies is that while knowledge about the system is acquired incrementally, substantial financial commitments, even make-or-break decisions, must be made upfront, essentially in the unknown. One practice that helps in dealing with this dichotomy is the smart embedding of contingencies and margins in the design to serve as buffers against surprises. This issue presents itself in full force in the aerospace industry, where unprecedented systems are formulated and committed to as a matter of routine. As more and more aerospace mission concepts are generated by concurrent design laboratories, it is imperative that such laboratories apply well thought-out contingency and margin structures to their designs. The first part of this publication provides an overview of resource management techniques and standards used in the aerospace industry. That is followed by a thought provoking treatise on margin policies. The expose presents the actual flight telemetry data recorded by the thermal discipline during several recent NASA Goddard Space Flight Center missions. The margins actually achieved in flight are compared against pre-flight predictions, and the appropriateness and the ramifications of having designed with rigid margins to bounding stacked worst case conditions are assessed. The second half of the paper examines the particular issues associated with the application of contingencies and margins in the concurrent engineering environment. In closure, a discipline-by-discipline disclosure of the contingency and margin policies in use at the Integrated Design Center at NASA s Goddard Space Flight Center is made.

  6. Concurrent Engineering for the Management of Research and Development

    Science.gov (United States)

    DelRosario, Ruben; Petersen, Paul F.; Keys, L. Ken; Chen, Injazz J.

    2004-01-01

    The Management of Research and Development (R&D) is facing the challenges of reducing time from R&D to customer, reducing the cost of R&D, having higher accountability for results (improved quality), and increasing focus on customers. Concurrent engineering (CE) has shown great success in the automotive and technology industries resulting in significant decreases in cycle time, reduction of total cost, and increases in quality and reliability. This philosophy of concurrency can have similar implications or benefits for the management of R&D organizations. Since most studies on the application of CE have been performed in manufacturing environments, research into the benefits of CE into other environments is needed. This paper presents research conducted at the NASA Glenn Research Center (GRC) investigating the application of CE in the management of an R&D organization. In particular the paper emphasizes possible barriers and enhancers that this environment presents to the successful implementation of CE. Preliminary results and recommendations are based on a series of interviews and subsequent surveys, from which data has been gathered and analyzed as part of the GRC's Continuous Improvement Process.

  7. Pulmonary Alveolar Proteinosis in an AIDS Patient without Concurrent Pulmonary Infection

    Directory of Open Access Journals (Sweden)

    Allen T Liu

    1995-01-01

    Full Text Available Patients with acquired immunodeficiency syndrome (AIDS are potentially at increased risk for developing secondary pulmonary alveolar proteinosis because of underlying immunosuppression and frequent opportunistic lung infections. This condition. however, has been diagnosed uncommonly in these patients and, with the exception of one previously reported case. only in the presence of concurrent pulmonary infection. The case of a 35-year-old male with AIDS who was found on open lung biopsy to have pulmonary alveolar proteinosis without evidence of associated lung infection is presented.

  8. The Space Suppliers And Manufacturer Database to Support Concurrent Engineering Sessions at DLR

    OpenAIRE

    Weiß, Andre; Schubert, Daniel; Quantius, Dominik

    2009-01-01

    Concurrent Engineering is a modern and effective discipline of the systems engineering process. During Concurrent Engineering sessions, an interdisciplinary team negotiates optimal configurations of the intended space system. The Space Suppliers And Manufacturers (SSAM) database was created with the goal to support engineers during the design process. The CE engineer can search through SSAM by using an interface to specify the right subsystem or component resulting in a list of...

  9. Applying Pareto multi-criteria decision making in concurrent engineering: A case study of polyethylene industry

    OpenAIRE

    Akbar A. Tabriz; Ahmad Ahmadi; Mohammad Hassan Maleki; Mohammad Ali Afshari; Javad S. Moradi

    2011-01-01

    Concurrent engineering (CE) is one of the widest known techniques for simultaneous planning of product and process design. In concurrent engineering, design processes are often complicated with multiple conflicting criteria and discrete sets of feasible alternatives. Thus multi-criteria decision making (MCDM) techniques are integrated into CE to perform concurrent design. This paper proposes a design framework governed by MCDM technique, which are in conflict in the sense of competing for com...

  10. Interface Management in Concurrent Engineering Facilities for Systems and Service Systems Engineering: A Model-based Approach

    OpenAIRE

    Gianni, Daniele; D'Ambrogio, Andrea; Schaus, Volker; Gerndt, Andreas; Lisi, Marco; De Simone, Pierluigi

    2014-01-01

    Concurrent engineering facilities (CEFs) are successfully used in the aeropsace sector to design systems and services that that fulfill the requirements. Model-based systems engineering (MBSE) enables the effective (i.e., unambiguous) communication in the collaborative activities within concurrent engineering and service systems engineering facilities. The advantages obtained by the MBSE approach can be further scaled up by an innovative approach that take into explicit account the representa...

  11. Aerospace Concurrent Engineering Design Teams: Current State, Next Steps and a Vision for the Future

    Science.gov (United States)

    Hihn, Jairus; Chattopadhyay, Debarati; Karpati, Gabriel; McGuire, Melissa; Borden, Chester; Panek, John; Warfield, Keith

    2011-01-01

    Over the past sixteen years, government aerospace agencies and aerospace industry have developed and evolved operational concurrent design teams to create novel spaceflight mission concepts and designs. These capabilities and teams, however, have evolved largely independently. In today's environment of increasingly complex missions with limited budgets it is becoming readily apparent that both implementing organizations and today's concurrent engineering teams will need to interact more often than they have in the past. This will require significant changes in the current state of practice. This paper documents the findings from a concurrent engineering workshop held in August 2010 to identify the key near term improvement areas for concurrent engineering capabilities and challenges to the long-term advancement of concurrent engineering practice. The paper concludes with a discussion of a proposed vision for the evolution of these teams over the next decade.

  12. Set-Based Concurrent Engineering process within the LeanPPD environment

    OpenAIRE

    Khan, Muhammad; Al-Ashaab, Ahmed; Doultsinou, Athanasia; Shehab, Essam; Ewers, Paul; Sulowski, Robert

    2011-01-01

    This paper presents a newly defined set-based concurrent engineering process, which the authors believe addresses some of the key challenges faced by engineering enterprises in the 21st century. The main principles of Set-Based Concurrent Engineering (SBCE) have been identified via an extensive literature review. Based on these principles the SBCE baseline model was developed. The baseline model defines the stages and activities which represent the product development proces...

  13. Concurrent Engineering with IT-Tools for successful industrial products in a global market

    DEFF Research Database (Denmark)

    Conrad, Finn

    2003-01-01

    The paper presents and discusses research results concerning Concurrent Engineering with IT-Tools for Successful Industrial Products on a Global Market. Concurrent Engineering, often is called just ¿CE¿, that is a systematic approach to the integrated, concurrent design of products and related...... on the world market and the increasing global public demands, requirements and regulations for protection of the environment are both driving forces and challenges for improving the development of control and engineering design. There has always been an ongoing desire to develop and design systems to improve...

  14. Computer aided system engineering for space construction

    Science.gov (United States)

    Racheli, Ugo

    1989-01-01

    This viewgraph presentation covers the following topics. Construction activities envisioned for the assembly of large platforms in space (as well as interplanetary spacecraft and bases on extraterrestrial surfaces) require computational tools that exceed the capability of conventional construction management programs. The Center for Space Construction is investigating the requirements for new computational tools and, at the same time, suggesting the expansion of graduate and undergraduate curricula to include proficiency in Computer Aided Engineering (CAE) though design courses and individual or team projects in advanced space systems design. In the center's research, special emphasis is placed on problems of constructability and of the interruptability of planned activity sequences to be carried out by crews operating under hostile environmental conditions. The departure point for the planned work is the acquisition of the MCAE I-DEAS software, developed by the Structural Dynamics Research Corporation (SDRC), and its expansion to the level of capability denoted by the acronym IDEAS**2 currently used for configuration maintenance on Space Station Freedom. In addition to improving proficiency in the use of I-DEAS and IDEAS**2, it is contemplated that new software modules will be developed to expand the architecture of IDEAS**2. Such modules will deal with those analyses that require the integration of a space platform's configuration with a breakdown of planned construction activities and with a failure modes analysis to support computer aided system engineering (CASE) applied to space construction.

  15. Integrated System-Level Optimization for Concurrent Engineering With Parametric Subsystem Modeling

    Science.gov (United States)

    Schuman, Todd; DeWeck, Oliver L.; Sobieski, Jaroslaw

    2005-01-01

    The introduction of concurrent design practices to the aerospace industry has greatly increased the productivity of engineers and teams during design sessions as demonstrated by JPL's Team X. Simultaneously, advances in computing power have given rise to a host of potent numerical optimization methods capable of solving complex multidisciplinary optimization problems containing hundreds of variables, constraints, and governing equations. Unfortunately, such methods are tedious to set up and require significant amounts of time and processor power to execute, thus making them unsuitable for rapid concurrent engineering use. This paper proposes a framework for Integration of System-Level Optimization with Concurrent Engineering (ISLOCE). It uses parametric neural-network approximations of the subsystem models. These approximations are then linked to a system-level optimizer that is capable of reaching a solution quickly due to the reduced complexity of the approximations. The integration structure is described in detail and applied to the multiobjective design of a simplified Space Shuttle external fuel tank model. Further, a comparison is made between the new framework and traditional concurrent engineering (without system optimization) through an experimental trial with two groups of engineers. Each method is evaluated in terms of optimizer accuracy, time to solution, and ease of use. The results suggest that system-level optimization, running as a background process during integrated concurrent engineering sessions, is potentially advantageous as long as it is judiciously implemented.

  16. Applying Pareto multi-criteria decision making in concurrent engineering: A case study of polyethylene industry

    Directory of Open Access Journals (Sweden)

    Akbar A. Tabriz

    2011-07-01

    Full Text Available Concurrent engineering (CE is one of the widest known techniques for simultaneous planning of product and process design. In concurrent engineering, design processes are often complicated with multiple conflicting criteria and discrete sets of feasible alternatives. Thus multi-criteria decision making (MCDM techniques are integrated into CE to perform concurrent design. This paper proposes a design framework governed by MCDM technique, which are in conflict in the sense of competing for common resources to achieve variously different performance objectives such as financial, functional, environmental, etc. The Pareto MCDM model is applied to polyethylene pipe concurrent design governed by four criteria to determine the best alternative design to Pareto-compromise design.

  17. Computer Aided Software Engineering workstation evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Kotcher, D.A.; Parish, R.B.; Sisson, A.M.; Wenzel, W.A.; Wiancko, B.E.

    1988-09-14

    This report presents an evaluation of interconnected high performance workstations. The evaluation specifically addresses the benefits to personnel engaged in Computer Aided Software Engineering (CASE) for the design and development of computer software aided by computer workstations. To narrow the scope of the CASE evaluation to a reasonable size, the class of workstations considered was limited to units having the following minimum capabilities: speed to issue 2 to 3 million instructions per second (Mips), 4 megabytes (MB) of central memory, 140 MB of local disk storage, a monitor with 1024 by 960 graphics resolution, and Ethernet compatibility. In addition, software requirements included a virtual memory implementation of the UNIX operating system, the defacto standard networking Transmission Control Protocol and Internet Protocol (TCP/IP), and the network file system (NFS). Support of selected third-party software, such as the TEMPLATE graphics software, and robust tools for software development were also required. These criteria are justified by the use of workstations for maintenance and support of large mainframe based FORTRAN computer programs. The evaluation concluded that workstations are excellent tools for CASE. 1 ref., 1 fig., 6 tabs.

  18. Design Model Data Exchange Between Concurrent Engineering Facilities by Means of Model Transformation

    OpenAIRE

    Fischer, Philipp M.; Schaus, Volker; Gerndt, Andreas

    2011-01-01

    The German Aerospace Center (DLR) is developing the software Virtual Satellite for use in their Concurrent Engineering Facility. Throughout the design process of a spacecraft the software supports engineers to store and manage the data and results of their engineering sessions. The European Cooperation for Space Standardization (ECSS) is promoting a new technical memorandum for model based data exchange across the facilities. In order to enable data exchange from Virtual Satellite's own mo...

  19. Teaching Scenario Development for Concurrent Engineering Practices Simulation.

    Science.gov (United States)

    Aguiar, Adriana F. S.; de Oliveira, Cristiano B. M.; Rozenfeld, Henrique; Omokawa, Rogerio

    In modern society, a company's competitive advantage is directly related to its capacity for product development. This paper describes the use of a Model Integrated Factory to simulate product development business processes for the education of engineers. (WRM)

  20. An Internet-enabled Integration of Concurrent Engineering with Co-design

    Institute of Scientific and Technical Information of China (English)

    WEN Quan; HE Jianmin

    2006-01-01

    In this paper, the Web-based integration methodology and framework have been developed to facilitate collaborative and concurrent engineering design in distributed manufacturing environments. The distributed concurrent engineering and co-design are discussed as key components in the mechanism. The related integration system is presented, which includes four functional modules: co-design, Web-based visualization, manufacturing analysis and look-up service. It can be used for a design team geographically distributed to organize a collaborative and concurrent engineering design effectively. In particular, the collaborative mechanism incorporated with Java-based and Internet-enabled technologies can generate extended strategies for design and planning. Thus, the proposed integration architecture enables the system to be generic, open and scalable. Finally, for the trend of global manufacturing, a case study of Internet-enabled collaborative optimization is introduced and a discussion on teamwork capability is made.

  1. Visualization aided system of hydropower engineering management%Visualization aided system of hydropower engineering management

    Institute of Scientific and Technical Information of China (English)

    Huang Yuan; Nie Miaojing; Yan Hongyan

    2012-01-01

    For the purpose of realizing the information visualization of hydropower engineering management, we construeted three kinds of graphics models sorted by hierarchy for system modelling, employed the construction simulation system to simulate the real-time construction behaviours, introduced the graphics rendering system to organize and update the virtual scene, and designed the interaction system to respond to the user-initiated and simulation-initiated events. So, the real-time, interactive visualization aided system of hydropower engineering management is developed. Eventually, the effectiveness and capabilities of the system are showed through the application examples in China.

  2. Use of Concurrent Engineering in Space Mission Design

    Science.gov (United States)

    Wall, S.

    2000-01-01

    In recent years, conceptual-phase (proposal level) design of space missions has been improved considerably. Team structures, tool linkage, specialized facilities known as design centers and scripted processes have been demonstrated to cut proposal-level engineering design time from a few months to a few weeks.

  3. Effective Concurrent Engineering with the Usage of Genetic Algorithms for Software Development

    OpenAIRE

    K.Alagarsamy; D.Sundar

    2012-01-01

    Software specifications are useful to the organizations to enforce a consistent approach in designing,implementing and the maintenance of the software. There are numerous principles employed for theassurance of the quality of the software. Concurrent engineering with Genetic algorithms have beenadopted for the software development. The results obtained are appreciable and detailed discussion isdone.

  4. Computer-aided engineering: the step beyond CAD/CAM

    Energy Technology Data Exchange (ETDEWEB)

    Hatfield, L.; Trost, S.R.; O' Brien, D.W.; Pomernacki, C.L.

    1981-11-06

    At Lawrence Livermore National Laboratory, the need for increased engineering productivity, coupled with increasingly difficult engineering problems, presents a significant challenge. Advances in computer technology coupled with successful CAD/CAM experiences suggest that computer-aided engineering (CAE) will help meet this challenge. Requirements for a CAE system are developed, a CAE system plan is outlined, and some remaining problem areas are discussed.

  5. Research on Concurrent Engineering Oriented Integrated Product Development Process Management System

    Institute of Scientific and Technical Information of China (English)

    Cao Jian; Zhang Shensheng; He Yuanjun

    2001-01-01

    In concurrent engineering, effective process management is the key to improve theefficiency and quality of product development. Although in project management system, workflowmanagement system and PDM system, process management functions are provided, they can notmeet the needs of product development. In this paper, we integrate the project management,workflow management and product management technique together and a concurrent engineeringoriented integrated product development process management system is proposed. The systemstructure, integrated product development model and running method are introduced. The practiceproves this system is powerful in supporting product development process.

  6. Concurrent engineering in the 21st century foundations, developments and challenges

    CERN Document Server

    Wognum, Nel; Verhagen, Wim

    2015-01-01

    Presenting the gradual evolution of the concept of Concurrent Engineering (CE),  and the technical, social methods and tools that have been developed, including the many theoretical and practical challenges that still exist, this book serves to summarize the achievements and current challenges of CE and will give readers a comprehensive picture of CE as researched and practiced in different regions of the world. Featuring in-depth analysis of complex real-life applications and experiences, this book demonstrates that Concurrent Engineering is used widely in many industries and that the same basic engineering principles can also be applied to new, emerging fields like sustainable mobility. Designed to serve as a valuable reference to industry experts, managers, students, researchers, and software developers, this book is intended to serve as both an introduction to development and as an analysis of the novel approaches and techniques of CE, as well as being a compact reference for more experienced readers.

  7. Critical issues and lessons learned in establishing concurrent international MS degree programs in engineering technology

    OpenAIRE

    O'Donnell, Gareth; Kuder, Matthias; Dyrenfurth, Michael; Murphy, Mike; Bertoline, Gary; Herrick, Robert; Newton, Kathryne; Sancho Samsó, María Ribera; Castell Ariño, Núria; Barnes, James L.

    2011-01-01

    Globalization, competitiveness, and innovation are frequently employed themes as governments, business and industry and universities attempt to respond to the challenges facing them. Clearly business as usual is not likely to be successful in the future. One strategic response for universities has been a significant impetus – in many parts of the world – towards dual, joint or concurrent degree programs involving international partners. It is perhaps not surprising that engineering is amon...

  8. The most economic cavity quantity in injection mould CAD based on concurrent engineering

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Presents the conception of concurrent engineering employed for CAD/CAM of injection moulds by closely combining the management science with the manufacturing techniques with the cost of processing, material cost, etc taken into consideration from the conceptural design to delivery of products and concludes with the results of analyses that the cost of finished plastic parts is lower, the production efficiency is higher while energy is saved.

  9. Estimation of Project Completion Time and Factors Analysis for Concurrent Engineering Project Management: A Simulation Approach

    OpenAIRE

    Huang, Enzhen; Chen, Shi-Jie

    2006-01-01

    Abstract In concurrent engineering projects, tasks are usually interdependent among each other that require much iteration before completion where the critical path method/program evaluation and review technique (CPM/PERT) may not be applicable to help estimate the project duration. In addition, carrying out a large-scaled project in a dynamic environment has to deal with various factors at the same time. W...

  10. Concurrent engineering in the context of the composite leisure boatbuilding industry

    OpenAIRE

    Sobey, Adam James

    2010-01-01

    Leisure boatbuilding is an industry that has tight profit margins and growing competition due to the global nature of the industry. It is a growth market with the number of high-earning potential customers increasing worldwide. For British boatbuilding to retain and increase its high standing within these global markets investment is required to develop larger profits and market share. Concurrent engineering is a method of design that has given large benefits to a multitude of industries but ...

  11. The impact of organizational culture on Concurrent Engineering, Design-for-Safety, and product safety performance.

    OpenAIRE

    A. Zhu; von Zedtwitz, M.; Assimakopoulos, D.; Fernandes, K

    2016-01-01

    This paper empirically extends the research on the relationships between organizational culture, new product development (NPD) practices, and product safety performance (PSP). Using Schein's conceptualization of culture (i.e., underlying assumptions, espoused values, and artifacts), we build and test a model among five variables: top management commitment to safety (MCS), group level product safety culture (PSC) at NPD, Concurrent Engineering (CE), Design-for-Safety (DFS), and product safety ...

  12. Barriers to the Uptake of Concurrent Engineering in the Nigerian Construction Industry

    OpenAIRE

    Nathaniel Anny Aniekwu; Igboanugo, Anthony C.

    2012-01-01

    It is the consensus of scholars that the productivity of the construction industry is very low when compared with other industries. Concurrent Engineering (CE), which has a primary goal of reducing the total time from designing a product to releasing it into the market, while creating better designs as well, has been identified as one of the concepts that has yielded effective adaptation in the construction industry. An exploratory survey was used to identify 63 variables with the capacity to...

  13. Task Decomposition Technique's Deduction and Application of Product Developing Process in Concurrent Engineering

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Task decomposition is a kind of powerful technique increasingly being used within industry as a pathway for achieving product's developing success. In this paper, topology's concept in modern mathematics is used for task decomposition technique's deduction in product developing process. It puts forward the views of resolvability, measurability and connectivity of tasks and their practical principles. Combined with an example of developing the typical mechanical product, it explains the implementing method of task decomposition in Concurrent Engineering (CE).

  14. Negotiation in collaborative assessment of design solutions: an empirical study on a Concurrent Engineering process

    OpenAIRE

    Martin, Géraldine; Détienne, Françoise; Lavigne, Elisabeth

    2007-01-01

    In Concurrent engineering, design solutions are not only produced by individuals specialized in a given field. Due to the team nature of the design activity, solutions are negotiated. Our objective is to analyse the argumentation processes leading to these negotiated solutions. These processes take place in the meetings which group together specialists with a co-design aim. We conducted cognitive ergonomics research work during the definition phase of an aeronautical design project in which t...

  15. Set-Based Concurrent Engineering Model for Automotive Electronic/Software Systems Development

    OpenAIRE

    Al-Ashaab, Ahmed; Howell, S.; Usowicz, K.; Hernando Anta, P.; Gorka, A.

    2009-01-01

    This paper is presenting a proposal of a novel approach to automotive electronic/software systems development. It is based on the combination of Set-Based Concurrent Engineering, a Toyota approach to product development, with the standard V-Model of software development. Automotive industry currently faces the problem of growing complexity of electronic/software systems. This issue is especially visible at the level of integration of these systems which is difficult and error-pron...

  16. PCACE-Personal-Computer-Aided Cabling Engineering

    Science.gov (United States)

    Billitti, Joseph W.

    1987-01-01

    PCACE computer program developed to provide inexpensive, interactive system for learning and using engineering approach to interconnection systems. Basically database system that stores information as files of individual connectors and handles wiring information in circuit groups stored as records. Directly emulates typical manual engineering methods of handling data, thus making interface between user and program very natural. Apple version written in P-Code Pascal and IBM PC version of PCACE written in TURBO Pascal 3.0

  17. Review of AIDS development. [airborne computers for reliability engineering

    Science.gov (United States)

    Vermeulen, H. C.; Danielsson, S. G.

    1981-01-01

    The operation and implementation of the aircraft integrated data system AIDS are described. The system is described as an engineering tool with strong emphasis on analysis of recorded information. The AIDS is primarily directed to the monitoring of parameters related to: the safety of the flight; the performance of the aircraft; the performance of the flight guidance system; and the performance and condition of the engines. The system provide short term trend analysis on a trend chart that is updated by the flight engineer on every flight that lasts more than 4 flight hours. Engine data prints are automatically presented during take-off and in the case of limit excedance, e.g., the print shows an automatically reported impending hotstarts on engine nr. 1. Other significant features are reported.

  18. From sashimi to zen-in : the evolution of concurrent engineering at Fuji Xerox

    OpenAIRE

    Umemoto, Katsuhiro; Endo, Atsushi; Machado, Marcelo

    2004-01-01

    This case study examines the evolution of R&D knowledge management at Japan’s business equipment maker Fuji Xerox, from the sashimi system, a Japanese origin of concurrent engineering, to its successor zen-in system, which is composed mainly of a real high-tech discussion room equipped with databases that provide technical information and two 70-inch displays that shows virtual but real-size, three-dimensional graphic models. We found that Fuji Xerox has chosen the “hybridization strategy” th...

  19. An Overview of Concurrent Engineering Research and Its Industrial Implementati on in Chinese Enterprises

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Concurrent Engineering (CE) is an effective way for enterprises to reengineer the product development processes and to improve the product develop ment abilities. In this paper, the existing status of product development in Chi nese manufacturing industry is analyzed, and the requirements of manufacturing t echnology for them are investigated. An overview of our CE R&D work is introduce d , including product modeling, DFA, DFM, QFD, PDM, and other enabling techn ologies. A case study of the CE pilot project is discussed. The industrial imple mentation and application in Chinese enterprises are summarized.

  20. A CORBA-Based Integration Platform of Product Development Process Management for Concurrent Engineering

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Product development process management plays an important role in concurrent engineering (CE). The integration platform is a useful tool for effectively supporting the software development and inte gration. Based on the analysis of practical requirements for product development process management for CE, a CORBA-based integration platform of product development process management (IP-PDPM) is de signed and developed. The design principles for IP-PDPM are described. The system architecture and func tions of the platform are given, the key technologies for the implementation of IP-PDPM are presented, the application integration mechanism and its implementation techniques are also detailed.

  1. Next-generation concurrent engineering: developing models to complement point designs

    Science.gov (United States)

    Morse, Elizabeth; Leavens, Tracy; Cohanim, Babak; Harmon, Corey; Mahr, Eric; Lewis, Brian

    2006-01-01

    Concurrent Engineering Design (CED) teams have made routine the rapid development of point designs for space missions. The Jet Propulsion Laboratory's Team X is now evolving into a 'next-generation CED; in addition to a point design, the Team develops a model of the local trade space. The process is a balance between the power of a model developing tools and the creativity of humal experts, enabling the development of a variety of trade models for any space mission. This paper reviews the modeling method and its practical implementation in the ED environment. Example results illustrate the benefit of this approach.

  2. PCACE- PERSONAL COMPUTER AIDED CABLING ENGINEERING

    Science.gov (United States)

    Billitti, J. W.

    1994-01-01

    A computerized interactive harness engineering program has been developed to provide an inexpensive, interactive system which is designed for learning and using an engineering approach to interconnection systems. PCACE is basically a database system that stores information as files of individual connectors and handles wiring information in circuit groups stored as records. This directly emulates the typical manual engineering methods of data handling, thus making the user interface to the program very natural. Data files can be created, viewed, manipulated, or printed in real time. The printed ouput is in a form ready for use by fabrication and engineering personnel. PCACE also contains a wide variety of error-checking routines including connector contact checks during hardcopy generation. The user may edit existing harness data files or create new files. In creating a new file, the user is given the opportunity to insert all the connector and harness boiler plate data which would be part of a normal connector wiring diagram. This data includes the following: 1) connector reference designator, 2) connector part number, 3) backshell part number, 4) cable reference designator, 5) cable part number, 6) drawing revision, 7) relevant notes, 8) standard wire gauge, and 9) maximum circuit count. Any item except the maximum circuit count may be left blank, and any item may be changed at a later time. Once a file is created and organized, the user is directed to the main menu and has access to the file boiler plate, the circuit wiring records, and the wiring records index list. The organization of a file is such that record zero contains the connector/cable boiler plate, and all other records contain circuit wiring data. Each wiring record will handle a circuit with as many as nine wires in the interface. The record stores the circuit name and wire count and the following data for each wire: 1) wire identifier, 2) contact, 3) splice, 4) wire gauge if different from standard

  3. Concurrent and Collaborative Engineering Implementation in an R and D Organization

    Science.gov (United States)

    DelRosario, Ruben; Davis, Jose M.; Keys, L. Ken

    2003-01-01

    Concurrent Engineering (CE), and Collaborative Engineering (or Collaborative Product Development - CPD) have emerged as new paradigms with significant impact in the development of new products and processes. With documented and substantiated success in the automotive and technology industries CE and, most recently, CPD are being touted as innovative management philosophies for many other business sectors including Research and De- velopment. This paper introduces two independent research initiatives conducted at the NASA Glenn Research Center (GRC) in Cleveland, Ohio investigating the application of CE and CPD in an RdiD environment. Since little research has been conducted in the use of CE and CPD in sectors other than the high mass production manufacturing, the objective of these independent studies is to provide a systematic evaluation of the applicability of these paradigms (concur- rent and collaborative) in a low/no production, service environment, in particular R&D.

  4. The Application of Concurrent Engineering Tools and Design Structure Matrix in Designing Tire

    Science.gov (United States)

    Ginting, Rosnani; Fachrozi Fitra Ramadhan, T.

    2016-02-01

    The development of automobile industry in Indonesia is growing rapidly. This phenomenon causes companies related to the automobile industry such as tire industry must develop products based on customers’ needs and considering the timeliness of delivering the product to the customer. It could be reached by applying strategic planning in developing an integrated concept of product development. This research was held in PT. XYZ that applied the sequential approach in designing and developing products. The need to improve in one stage of product development could occur re-designing that needs longer time in developing a new product. This research is intended to get an integrated product design concept of tire pertaining to the customer's needs using Concurrent Engineering Tools by implementing the two-phased of product development. The implementation of Concurrent Engineering approach results in applying the stage of project planning, conceptual design, and product modules. The product modules consist of four modules that using Product Architecture - Design Structure Matrix to ease the designing process of new product development.

  5. Computer-Aided Engineering Of Cabling

    Science.gov (United States)

    Billitti, Joseph W.

    1989-01-01

    Program generates data sheets, drawings, and other information on electrical connections. DFACS program, centered around single data base, has built-in menus providing easy input of, and access to, data for all personnel involved in system, subsystem, and cabling. Enables parallel design of circuit-data sheets and drawings of harnesses. Also recombines raw information to generate automatically various project documents and drawings, including index of circuit-data sheets, list of electrical-interface circuits, lists of assemblies and equipment, cabling trees, and drawings of cabling electrical interfaces and harnesses. Purpose of program to provide engineering community with centralized data base for putting in, and gaining access to, functional definition of system as specified in terms of details of pin connections of end circuits of subsystems and instruments and data on harnessing. Primary objective to provide instantaneous single point of interchange of information, thus avoiding

  6. Selecting and effectively using a computer aided software engineering tool

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, D.L.

    1989-01-01

    Software engineering is a science by which user requirements are translated into a quality software product. Computer Aided Software Engineering (CASE) is the scientific application of a set of tools and methods to a software which results in high-quality, defect-free, and maintainable software products. The Computer Systems Engineering (CSE) group of Separations Technology at the Savannah River Site has successfully used CASE tools to produce high-quality, reliable, and maintainable software products. This paper details the selection process CSE used to acquire a commonly available CASE product and how the CSE group effectively used this CASE tool to consistently produce quality software. 9 refs.

  7. The Design of a Primary Flight Trainer using Concurrent Engineering Concepts

    Science.gov (United States)

    Ladesic, James G.; Eastlake, Charles N.; Kietzmann, Nicholas H.

    1993-01-01

    Concurrent Engineering (CE) concepts seek to coordinate the expertise of various disciplines from initial design configuration selection through product disposal so that cost efficient design solutions may be achieve. Integrating this methodology into an undergraduate design course sequence may provide a needed enhancement to engineering education. The Advanced Design Program (ADP) project at Embry-Riddle Aeronautical University (EMU) is focused on developing recommendations for the general aviation Primary Flight Trainer (PFT) of the twenty first century using methods of CE. This project, over the next two years, will continue synthesizing the collective knowledge of teams composed of engineering students along with students from other degree programs, their faculty, and key industry representatives. During the past year (Phase I). conventional trainer configurations that comply with current regulations and existing technologies have been evaluated. Phase I efforts have resulted in two baseline concepts, a high-wing, conventional design named Triton and a low-wing, mid-engine configuration called Viper. In the second and third years (Phases II and III). applications of advanced propulsion, advanced materials, and unconventional airplane configurations along with military and commercial technologies which are anticipated to be within the economic range of general aviation by the year 2000, will be considered.

  8. NASA's Planetary Science Summer School: Training Future Mission Leaders in a Concurrent Engineering Environment

    Science.gov (United States)

    Mitchell, K. L.; Lowes, L. L.; Budney, C. J.; Sohus, A.

    2014-12-01

    NASA's Planetary Science Summer School (PSSS) is an intensive program for postdocs and advanced graduate students in science and engineering fields with a keen interest in planetary exploration. The goal is to train the next generation of planetary science mission leaders in a hands-on environment involving a wide range of engineers and scientists. It was established in 1989, and has undergone several incarnations. Initially a series of seminars, it became a more formal mission design experience in 1999. Admission is competitive, with participants given financial support. The competitively selected trainees develop an early mission concept study in teams of 15-17, responsive to a typical NASA Science Mission Directorate Announcement of Opportunity. They select the mission concept from options presented by the course sponsors, based on high-priority missions as defined by the Decadal Survey, prepare a presentation for a proposal authorization review, present it to a senior review board and receive critical feedback. Each participant assumes multiple roles, on science, instrument and project teams. They develop an understanding of top-level science requirements and instrument priorities in advance through a series of reading assignments and webinars help trainees. Then, during the five day session at Jet Propulsion Laboratory, they work closely with concurrent engineers including JPL's Advanced Projects Design Team ("Team X"), a cross-functional multidisciplinary team of engineers that utilizes concurrent engineering methodologies to complete rapid design, analysis and evaluation of mission concept designs. All are mentored and assisted directly by Team X members and course tutors in their assigned project roles. There is a strong emphasis on making difficult trades, simulating a real mission design process as accurately as possible. The process is intense and at times dramatic, with fast-paced design sessions and late evening study sessions. A survey of PSSS alumni

  9. Concurrent engineering solution for the design of ship and offshore bracket parts and fabrication process

    Science.gov (United States)

    Kim, Tae-Won; Lim, Sang-Sub; Seok, Ho-Hyun; Kang, Chung-Gil

    2013-09-01

    Brackets in ships and offshore structures are added structures that can endure stress concentrations. In this study, a concurrent engineering solution was proposed, and a high strength low carbon cast steel alloy applicable to offshore structures was designed and developed. The yield strength and ultimate tensile strength of the designed steel were 480 and 600 MPa, respectively. The carbon equivalent of the steel was 0.446 with a weld crack susceptibility index of 0.219. The optimal structural design of the brackets for offshore structures was evaluated using ANSYS commercial software. The possibility of replacing an assembly of conventional built-up brackets with a single casting bulb bracket was verified. The casting process was simulated using MAGMAsoft commercial software, and a casting fabrication process was designed. For the proposed bulb bracket, it was possible to reduce the size and weight by approximately 30% and 50%, respectively, compared to the conventional type of bracket.

  10. Microstereolithography-based computer-aided manufacturing for tissue engineering.

    Science.gov (United States)

    Cho, Dong-Woo; Kang, Hyun-Wook

    2012-01-01

    Various solid freeform fabrication technologies have been introduced for constructing three-dimensional (3-D) freeform structures. Of these, microstereolithography (MSTL) technology performs the best in 3-D space because it not only has high resolution, but also fast fabrication speed. Using this technology, 3-D structures with mesoscale size and microscale resolution are achievable. Many researchers have been trying to apply this technology to tissue engineering to construct medically applicable scaffolds, which require a 3-D shape that fits a defect with a mesoscale size and microscale inner architecture for efficient regeneration of artificial tissue. This chapter introduces the principles of MSTL technology and representative systems. It includes fabrication and computer-aided design/computer-aided manufacturing (CAD/CAM) processes to show the automation process by which measurements from medical images are used to fabricate the required 3-D shape. Then, various tissue engineering applications based on MSTL are summarized.

  11. Computer-aided dental prostheses construction using reverse engineering.

    Science.gov (United States)

    Solaberrieta, E; Minguez, R; Barrenetxea, L; Sierra, E; Etxaniz, O

    2014-01-01

    The implementation of computer-aided design/computer-aided manufacturing (CAD/CAM) systems with virtual articulators, which take into account the kinematics, constitutes a breakthrough in the construction of customised dental prostheses. This paper presents a multidisciplinary protocol involving CAM techniques to produce dental prostheses. This protocol includes a step-by-step procedure using innovative reverse engineering technologies to transform completely virtual design processes into customised prostheses. A special emphasis is placed on a novel method that permits a virtual location of the models. The complete workflow includes the optical scanning of the patient, the use of reverse engineering software and, if necessary, the use of rapid prototyping to produce CAD temporary prostheses.

  12. Domain-specific languages and diagram customization for a concurrent engineering environment

    Science.gov (United States)

    Cole, B.; Dubos, G.; Banazadeh, P.; Reh, J.; Case, K.; Wang, Y.; Jones, S.; Picha, F.

    A major open question for advocates of Model-Based Systems Engineering (MBSE) is the question of how system and subsystem engineers will work together. The Systems Modeling Language (SysML), like any language intended for a large audience, is in tension between the desires for simplicity and for expressiveness. In order to be more expressive, many specialized language elements may be introduced, which will unfortunately make a complete understanding of the language a more daunting task. While this may be acceptable for systems modelers, it will increase the challenge of including subsystem engineers in the modeling effort. One possible answer to this situation is the use of Domain-Specific Languages (DSL), which are fully supported by the Unified Modeling Language (UML). SysML is in fact a DSL for systems engineering. The expressive power of a DSL can be enhanced through the use of diagram customization. Various domains have already developed their own schematic vocabularies. Within the space engineering community, two excellent examples are the propulsion and telecommunication subsystems. A return to simple box-and-line diagrams (e.g., the SysML Internal Block Diagram) are in many ways a step backward. In order allow subsystem engineers to contribute directly to the model, it is necessary to make a system modeling tool at least approximate in accessibility to drawing tools like Microsoft PowerPoint and Visio. The challenge is made more extreme in a concurrent engineering environment, where designs must often be drafted in an hour or two. In the case of the Jet Propulsion Laboratory's Team X concurrent design team, a subsystem is specified using a combination of PowerPoint for drawing and Excel for calculation. A pilot has been undertaken in order to meld the drawing portion and the production of master equipment lists (MELs) via a SysML authoring tool, MagicDraw. Team X currently interacts with its customers in a process of sharing presentations. There are severa

  13. Domain-Specific Languages and Diagram Customization for a Concurrent Engineering Environment

    Science.gov (United States)

    Cole, Bjorn; Dubos, Greg; Banazadeh, Payam; Reh, Jonathan; Case, Kelley; Wang, Yeou-Fang; Jones, Susan; Picha, Frank

    2013-01-01

    A major open question for advocates of Model-Based Systems Engineering (MBSE) is the question of how system and subsystem engineers will work together. The Systems Modeling Language (SysML), like any language intended for a large audience, is in tension between the desires for simplicity and for expressiveness. In order to be more expressive, many specialized language elements may be introduced, which will unfortunately make a complete understanding of the language a more daunting task. While this may be acceptable for systems modelers, it will increase the challenge of including subsystem engineers in the modeling effort. One possible answer to this situation is the use of Domain-Specific Languages (DSL), which are fully supported by the Unified Modeling Language (UML). SysML is in fact a DSL for systems engineering. The expressive power of a DSL can be enhanced through the use of diagram customization. Various domains have already developed their own schematic vocabularies. Within the space engineering community, two excellent examples are the propulsion and telecommunication subsystems. A return to simple box-and-line diagrams (e.g., the SysML Internal Block Diagram) are in many ways a step backward. In order allow subsystem engineers to contribute directly to the model, it is necessary to make a system modeling tool at least approximate in accessibility to drawing tools like Microsoft PowerPoint and Visio. The challenge is made more extreme in a concurrent engineering environment, where designs must often be drafted in an hour or two. In the case of the Jet Propulsion Laboratory's Team X concurrent design team, a subsystem is specified using a combination of PowerPoint for drawing and Excel for calculation. A pilot has been undertaken in order to meld the drawing portion and the production of master equipment lists (MELs) via a SysML authoring tool, MagicDraw. Team X currently interacts with its customers in a process of sharing presentations. There are several

  14. Pendekatan Concurrent Engineering Tools pada Proses Perancangan Produk dengan Metode Quality Function Deployment dan Design Structure Matrix

    OpenAIRE

    Widjaya, Hady

    2014-01-01

    Desain memegang peranan penting dalam memproduksi produk spring bed pada implementasi concurrent engineering. Permasalahan pada penelitian ini yaitu terjadinya proses redesign dalam proses pengembangan produk spring bed 6 feet di PT Ocean Centra Furnindo karena terjadi penyesuaian kembali rancangan akibat dari tahapan dalam proses perancangan dilaksanakan setelah penyelesaian tahapan sebelumnya dan tidak terintegrasinya departemen dalam perusahaan. Penelitian ini bertujuan untuk menyederhanak...

  15. Project-Based Teaching-Learning Computer-Aided Engineering Tools

    Science.gov (United States)

    Simoes, J. A.; Relvas, C.; Moreira, R.

    2004-01-01

    Computer-aided design, computer-aided manufacturing, computer-aided analysis, reverse engineering and rapid prototyping are tools that play an important key role within product design. These are areas of technical knowledge that must be part of engineering and industrial design courses' curricula. This paper describes our teaching experience of…

  16. A computer aided engineering tool for ECLS systems

    Science.gov (United States)

    Bangham, Michal E.; Reuter, James L.

    1987-01-01

    The Computer-Aided Systems Engineering and Analysis tool used by NASA for environmental control and life support system design studies is capable of simulating atmospheric revitalization systems, water recovery and management systems, and single-phase active thermal control systems. The designer/analysis interface used is graphics-based, and allows the designer to build a model by constructing a schematic of the system under consideration. Data management functions are performed, and the program is translated into a format that is compatible with the solution routines.

  17. Space Station Freedom - Configuration management approach to supporting concurrent engineering and total quality management. [for NASA Space Station Freedom Program

    Science.gov (United States)

    Gavert, Raymond B.

    1990-01-01

    Some experiences of NASA configuration management in providing concurrent engineering support to the Space Station Freedom program for the achievement of life cycle benefits and total quality are discussed. Three change decision experiences involving tracing requirements and automated information systems of the electrical power system are described. The potential benefits of concurrent engineering and total quality management include improved operational effectiveness, reduced logistics and support requirements, prevention of schedule slippages, and life cycle cost savings. It is shown how configuration management can influence the benefits attained through disciplined approaches and innovations that compel consideration of all the technical elements of engineering and quality factors that apply to the program development, transition to operations and in operations. Configuration management experiences involving the Space Station program's tiered management structure, the work package contractors, international partners, and the participating NASA centers are discussed.

  18. Computer-aided Reverse Engineering for Rapid Replacement of Parts

    Directory of Open Access Journals (Sweden)

    D.K. Pal

    2006-04-01

    Full Text Available Indigenous product development using conventional means involves a relatively long leadtime and cost, especially for replacing worn out and broken parts. This paper presentsmethodologies and technologies for computer-aided reverse engineering, illustrated by a reallifecase study of an aluminium alloy separator body of a hydraulic filter assembly for the specialarmy vehicle. It involved reconstruction of part geometry using 3-D scanning, materialidentification using spectrometry, casting process optimisation using simulation software, andfabrication of prototype and tooling using rapid prototyping systems. It was found that thefabrication of wax patterns directly from reverse-engineered CAD data in a suitable rapidprototyping system (such as thermojet, followed by conventional investment casting, gives areliable and economic route for rapid development of one-off intricate parts for the replacementpurpose.

  19. Computer aided systems human engineering: A hypermedia tool

    Science.gov (United States)

    Boff, Kenneth R.; Monk, Donald L.; Cody, William J.

    1992-01-01

    The Computer Aided Systems Human Engineering (CASHE) system, Version 1.0, is a multimedia ergonomics database on CD-ROM for the Apple Macintosh II computer, being developed for use by human system designers, educators, and researchers. It will initially be available on CD-ROM and will allow users to access ergonomics data and models stored electronically as text, graphics, and audio. The CASHE CD-ROM, Version 1.0 will contain the Boff and Lincoln (1988) Engineering Data Compendium, MIL-STD-1472D and a unique, interactive simulation capability, the Perception and Performance Prototyper. Its features also include a specialized data retrieval, scaling, and analysis capability and the state of the art in information retrieval, browsing, and navigation.

  20. HIV/AIDS e Treinamento Concorrente: a Revisão Sistemática HIV/Aids and Concurrent Training: Systematic Review

    Directory of Open Access Journals (Sweden)

    Alexandre Ramos Lazzarotto

    2010-04-01

    to improve aerobic and strength capacities with shorter time of training and stands out within the used methods. It is crucial to understand this syndrome's characteristics for the best application of physical exercise in the HIV infected patients. Therefore, the aim of this study is to review the main HIV infection characteristics and the evidence available on concurrent training with single and multiple sets in immunological, virological, cardiorespiratory and neuromuscular parameters in subjects living with HIV/AIDS. A systematic review of papers published from 2000-2007 in the Scielo and Pubmed database, as well as theses and dissertations on Physical Education, Sports and Health fields from the digital library totalizing 8 studies, was performed. Evidence from these 8 investigated studies showed that concurrent training, both with single and multiple sets, improves cardiorespiratory and neuromuscular parameters. However, the results in the immunological and virological parameters are not completely understood, especially on protocols with single sets.

  1. A Data-Flow Based Coordination Approach to Concurrent Software Engineering

    NARCIS (Netherlands)

    F. Penczek; W. Cheng; C. Grelck; R. Kirner; B. Scheuermann; A. Shafarenko

    2012-01-01

    In this paper we present S-Net, a coordination language based on dataflow principles, intended for design of concurrent software. The language is introduced and then used for programming a concurrent solver for a combinatorial optimisation problem. We present the analysis and tracing facilities of o

  2. CT colonography: effect of computer-aided detection of colonic polyps as a second and concurrent reader for general radiologists with moderate experience in CT colonography

    Energy Technology Data Exchange (ETDEWEB)

    Mang, Thomas; Ringel, Helmut; Weber, Michael [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Bogoni, Luca; Anand, Vikram X.; Hermosillo, Gerardo; Raykar, Vikas; Salganicoff, Marcos; Wolf, Matthias [H IM SY US, Siemens Medical Solutions, Malvern, PA (United States); Chandra, Dass [Temple University, Philadelphia, PA (United States); Curtin, Andrew J. [Tristate Imaging Consultants, Abington, PA (United States); Lev-Toaff, Anna S. [University of Pennsylvania, Philadelphia, PA (United States); Noah, Ralph [Diagnostic Imaging Associates, Wilmington, DE (United States); Shaw, Robert [The Chester County Hospital, West Chester, PA (United States); Summerton, Susan [Albert Einstein Medical Center, Philadelphia, PA (United States); Tappouni, Rafel F.R. [Wake Forest University School of Medicine, Winston-Salem, NC (United States); Obuchowski, Nancy A. [Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, Ohio (United States)

    2014-07-15

    To assess the effectiveness of computer-aided detection (CAD) as a second reader or concurrent reader in helping radiologists who are moderately experienced in computed tomographic colonography (CTC) to detect colorectal polyps. Seventy CTC datasets (34 patients: 66 polyps ≥6 mm; 36 patients: no abnormalities) were retrospectively reviewed by seven radiologists with moderate CTC experience. After primary unassisted evaluation, a CAD second read and, after a time interval of ≥4 weeks, a CAD concurrent read were performed. Areas under the receiver operating characteristic (ROC) curve (AUC), along with per-segment, per-polyp and per-patient sensitivities, and also reading times, were calculated for each reader with and without CAD. Of seven readers, 86 % and 71 % achieved a higher accuracy (segment-level AUC) when using CAD as second and concurrent reader respectively. Average segment-level AUCs with second and concurrent CAD (0.853 and 0.864) were significantly greater (p < 0.0001) than average AUC in the unaided evaluation (0.781). Per-segment, per-polyp, and per-patient sensitivities for polyps ≥6 mm were significantly higher in both CAD reading paradigms compared with unaided evaluation. Second-read CAD reduced readers' average segment and patient specificity by 0.007 and 0.036 (p = 0.005 and 0.011), respectively. CAD significantly improves the sensitivities of radiologists moderately experienced in CTC for polyp detection, both as second reader and concurrent reader. (orig.)

  3. CT colonography: effect of computer-aided detection of colonic polyps as a second and concurrent reader for general radiologists with moderate experience in CT colonography

    International Nuclear Information System (INIS)

    To assess the effectiveness of computer-aided detection (CAD) as a second reader or concurrent reader in helping radiologists who are moderately experienced in computed tomographic colonography (CTC) to detect colorectal polyps. Seventy CTC datasets (34 patients: 66 polyps ≥6 mm; 36 patients: no abnormalities) were retrospectively reviewed by seven radiologists with moderate CTC experience. After primary unassisted evaluation, a CAD second read and, after a time interval of ≥4 weeks, a CAD concurrent read were performed. Areas under the receiver operating characteristic (ROC) curve (AUC), along with per-segment, per-polyp and per-patient sensitivities, and also reading times, were calculated for each reader with and without CAD. Of seven readers, 86 % and 71 % achieved a higher accuracy (segment-level AUC) when using CAD as second and concurrent reader respectively. Average segment-level AUCs with second and concurrent CAD (0.853 and 0.864) were significantly greater (p < 0.0001) than average AUC in the unaided evaluation (0.781). Per-segment, per-polyp, and per-patient sensitivities for polyps ≥6 mm were significantly higher in both CAD reading paradigms compared with unaided evaluation. Second-read CAD reduced readers' average segment and patient specificity by 0.007 and 0.036 (p = 0.005 and 0.011), respectively. CAD significantly improves the sensitivities of radiologists moderately experienced in CTC for polyp detection, both as second reader and concurrent reader. (orig.)

  4. Painting Concurrent Engineering during Automotive Development%汽车开发中的涂装同步工程

    Institute of Scientific and Technical Information of China (English)

    华云

    2009-01-01

    @@ 1前言 同步工程(SE,Simultaneous Engineering/Concurrent Engineering)是对产品开发及其相关性过程(包括制造过程和支持过程)进行并行、一体化设计的一种系统化的工作模式,这种工作模式力图使设计人员从一开始即考虑到产品全生命周期(从概念形成到产品报废)中的所有因素.

  5. Use of computer-aided-engineering (CAE) for configuration management

    International Nuclear Information System (INIS)

    For nearly 25 years, Electricite de France (EDF) has been designing and building nuclear power plants, and now has more than 50 in operation. During this period, EDF has faced problems common to all designers and operators. The author discusses two major aspects which must be dealt with to design a power plant: installation design and operational description. In both cases, the designer has to ensure that all parameters conform to the design requirements and that all documents are consistent with each other. For the operational description, the most important part of the job is to check and maintain consistency between the various documents: P and ID's, functional diagrams, cable networks, procedures, data management and also installation drawings. The author discusses how EDF has chosen two computer aided design softwares---PDMS and PHENIX---and has built a powerful engineering system around them

  6. Computer- Aided Design in Power Engineering Application of Software Tools

    CERN Document Server

    Stojkovic, Zlatan

    2012-01-01

    This textbooks demonstrates the application of software tools in solving a series of problems from the field of designing power system structures and systems. It contains four chapters: The first chapter leads the reader through all the phases necessary in the procedures of computer aided modeling and simulation. It guides through the complex problems presenting on the basis of eleven original examples. The second chapter presents  application of software tools in power system calculations of power systems equipment design. Several design example calculations are carried out using engineering standards like MATLAB, EMTP/ATP, Excel & Access, AutoCAD and Simulink. The third chapters focuses on the graphical documentation using a collection of software tools (AutoCAD, EPLAN, SIMARIS SIVACON, SIMARIS DESIGN) which enable the complete automation of the development of graphical documentation of a power systems. In the fourth chapter, the application of software tools in the project management in power systems ...

  7. Computer-aided detection of lung nodules on multidetector CT in concurrent-reader and second-reader modes: A comparative study

    International Nuclear Information System (INIS)

    Purpose: To compare the reading times and detection performances of radiologists in concurrent-reader and second-reader modes of computer-aided detection (CAD) for lung nodules on multidetector computed tomography (CT). Materials and Methods: Fifty clinical multidetector CT datasets containing nodules up to 20 mm in diameter were retrospectively collected. For the detection and rating of non-calcified nodules larger than 4 mm in diameter, 6 radiologists (3 experienced radiologists and 3 resident radiologists) independently interpreted these datasets twice, once with concurrent-reader CAD and once with second-reader CAD. The reference standard of nodules in the datasets was determined by the consensus of two experienced chest radiologists. The reading times and detection performances in the two modes of CAD were statistically compared, where jackknife free-response receiver operating characteristic (JAFROC) analysis was used for the comparison of detection performances. Results: Two hundreds and seven nodules constituted the reference standard. Reading time was significantly shorter in the concurrent-reader mode than in the second-reader mode, with the mean reading time for the 6 radiologists being 132 s with concurrent-reader CAD and 210 s with second-reader CAD (p < 0.01). JAFROC analysis revealed no significant difference between the detection performances in the two modes, with the average figure-of-merit value for the 6 radiologists being 0.70 with concurrent-reader CAD and 0.72 with second-reader CAD (p = 0.35). Conclusion: In CAD for lung nodules on multidetector CT, the concurrent-reader mode is more time-efficient than the second-reader mode, and there can be no significant difference between the two modes in terms of detection performance of radiologists

  8. Accelerating Battery Design Using Computer-Aided Engineering Tools: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Pesaran, A.; Heon, G. H.; Smith, K.

    2011-01-01

    Computer-aided engineering (CAE) is a proven pathway, especially in the automotive industry, to improve performance by resolving the relevant physics in complex systems, shortening the product development design cycle, thus reducing cost, and providing an efficient way to evaluate parameters for robust designs. Academic models include the relevant physics details, but neglect engineering complexities. Industry models include the relevant macroscopic geometry and system conditions, but simplify the fundamental physics too much. Most of the CAE battery tools for in-house use are custom model codes and require expert users. There is a need to make these battery modeling and design tools more accessible to end users such as battery developers, pack integrators, and vehicle makers. Developing integrated and physics-based CAE battery tools can reduce the design, build, test, break, re-design, re-build, and re-test cycle and help lower costs. NREL has been involved in developing various models to predict the thermal and electrochemical performance of large-format cells and has used in commercial three-dimensional finite-element analysis and computational fluid dynamics to study battery pack thermal issues. These NREL cell and pack design tools can be integrated to help support the automotive industry and to accelerate battery design.

  9. The ultimate CASE (Computer-Aided Software Engineering) tool

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, J.K.

    1990-01-01

    The theory and practice of information engineering is being actively developed at Sandia National Laboratories. The main output of Sandia is information. Information is created, analyzed and distributed. It is the life blood of our design laboratory. The proper management of information will have a large, positive impact on staff productivity. In order to achieve the potential benefits of shared information a commonly understood approach is needed, and the approach must be implemented in a CASE (Computer-Aided Software Engineering) tool that spans the entire life cycle of information. The commonly understood approach used at Sandia is natural language. More specifically, it is a structured subset of English. Users and system developers communicate requirements and commitments that they both understand. The approach is based upon NIAM (Nijssen's Information Analysis Methodology). In the last three years four NIAM training classes have been given at Sandia. The classes were all at the introductory level, with the latest class last October having an additional seminar highlighting successful projects. The continued growth in applications using NIAM requires an advanced class. The class will develop an information model for the Ultimate CASE Tool.'' This paper presents the requirements that have been established for the Ultimate CASE Tool'' and presents initial models. 4 refs., 1 tab.

  10. Penerapan Concurrent Engineering Tools Dan Design Structure Matrix Pada Perancangan Produk Ban

    OpenAIRE

    Ramadhan, T. Fachrozi Fitra

    2015-01-01

    Perkembangan industri mobil di Indonesia yang semakin pesat menyebabkan perusahaan-perusahaan yang terkait dengan industri mobil seperti produk ban harus mampu mengembangkan produk yang sesuai dengan kebutuhan konsumen dengan tetap mempertimbangkan faktor ketepatan waktu produk sampai ke tangan konsumen. Tujuan tersebut dapat dicapai dengan menerapkan rencana strategis dalam mengembangkan suatu konsep terintegrasi dalam proses pengembangan produk. Penelitian yang berjudul Penerapan Concurrent...

  11. Design of a modular product architecture and a cellular manufacturing layout : A concurrent engineering approach

    NARCIS (Netherlands)

    Slomp, J; McGinnis, LF; Ahmad, MM; Sullivan, WG

    1996-01-01

    This paper formalizes the problem of a concurrent design of a modular product architecture and a cellular manufacturing layout and presents a way to deal with this design problem. First, the different types of a modular product architecture are explained as well as important implications of modulari

  12. A new nano-engineered hierarchical membrane for concurrent removal of surfactant and oil from oil-in-water nanoemulsion

    Science.gov (United States)

    Qin, Detao; Liu, Zhaoyang; Bai, Hongwei; Sun, Darren Delai; Song, Xiaoxiao

    2016-04-01

    Surfactant stabilized oil-in-water nanoemulsions pose a severe threat to both the environment and human health. Recent development of membrane filtration technology has enabled efficient oil removal from oil/water nanoemulsion, however, the concurrent removal of surfactant and oil remains unsolved because the existing filtration membranes still suffer from low surfactant removal rate and serious surfactant-induced fouling issue. In this study, to realize the concurrent removal of surfactant and oil from nanoemulsion, a novel hierarchically-structured membrane is designed with a nanostructured selective layer on top of a microstructured support layer. The physical and chemical properties of the overall membrane, including wettability, surface roughness, electric charge, thickness and structures, are delicately tailored through a nano-engineered fabrication process, that is, graphene oxide (GO) nanosheet assisted phase inversion coupled with surface functionalization. Compared with the membrane fabricated by conventional phase inversion, this novel membrane has four times higher water flux, significantly higher rejections of both oil (~99.9%) and surfactant (as high as 93.5%), and two thirds lower fouling ratio when treating surfactant stabilized oil-in-water nanoemulsion. Due to its excellent performances and facile fabrication process, this nano-engineered membrane is expected to have wide practical applications in the oil/water separation fields of environmental protection and water purification.

  13. 基于并行工程的SI体系住宅建设研究%Research on Housing Construction of SI System Based on Concurrent Engineering

    Institute of Scientific and Technical Information of China (English)

    李忠富; 何雨薇

    2016-01-01

    总结串行生产方式的缺点与并行工程思想的特点,讨论并行工程应用在SI住宅建设全寿命周期中的必要性和目标;研究并行工程思想在SI住宅建设全寿命周期过程中的应用,建立基于并行工程理论的SI住宅全寿命周期生产、运营系统;研究认为并行工程对于提升SI住宅建设效率有显著作用。%By summing the characters of the Concurrent Engineering and the shortcomings of the serial production modes,this paper discusses the necessity and the objective of using Concurrent Engineering in the life long construction of SI residential and then researches how to use the Concurrent Engineering in the construction of SI residential. Then,builds production and operation system of the life cycle construction of SI residential based on the Concurrent Engineering. Finally,reaches the conclusion that the Concurrent Engineering shows great effect in the efficiency of the life cycle construction of SI residential.

  14. The Concurrent Engineering Design Paradigm Is Now Fully Functional for Graphics Education

    Science.gov (United States)

    Krueger, Thomas J.; Barr, Ronald E.

    2007-01-01

    Engineering design graphics education has come a long way in the past two decades. The emergence of solid geometric modeling technology has become the focal point for the graphical development of engineering design ideas. The main attraction of this 3-D modeling approach is the downstream application of the data base to analysis and…

  15. An overview of interactive computer graphics and its application to computer-aided engineering and design

    International Nuclear Information System (INIS)

    The purpose of this brief birds-eye view of interactive graphics is to list the key ideas, and to show how one of the most important application areas, Computer Aided Engineering/Design takes advantage of it. (orig.)

  16. Progress of the Computer-Aided Engineering of Electric Drive Vehicle Batteries (CAEBAT) (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Pesaran, A. A.; Han, T.; Hartridge, S.; Shaffer, C.; Kim, G. H.; Pannala, S.

    2013-06-01

    This presentation, Progress of Computer-Aided Engineering of Electric Drive Vehicle Batteries (CAEBAT) is about simulation and computer-aided engineering (CAE) tools that are widely used to speed up the research and development cycle and reduce the number of build-and-break steps, particularly in the automotive industry. Realizing this, DOE?s Vehicle Technologies Program initiated the CAEBAT project in April 2010 to develop a suite of software tools for designing batteries.

  17. Review of research and development of computer-aided Kansei Engineering

    Institute of Scientific and Technical Information of China (English)

    Li LIN; Chengqi XUE

    2009-01-01

    Kansei Engineering is an important research approach and has become the hotspot of research in design fields. The concept of Kansei Engineering is introduced based on the investigation of related literatures. The working process and the key technology of computer-aided Kansei Engineering systems are discussed. Finally, the development trend of Kansei Engineering is outlined according to the development of computer and networking technology.

  18. A Generic Systems Engineering Method for Concurrent Development of Products and Manufacturing Equipment

    OpenAIRE

    Puik, Erik; Gielen, Paul; van Moergestel, Leo; Ceglarek, Darek

    2014-01-01

    International audience Manufacturing is getting more competitive with time due to continuously increasing global competition. Late market introduction decreases the economic lifecycle of products and reduces return on investments. Reconfigurable Manufacturing Systems (RMS) reduce the time to market because the process of equipment configuration is less time consuming than engineering it from scratch. This paper presents a scientific framework, to be applied as an engineering design tool, t...

  19. Multilevel Predictors of Concurrent Opioid Use during Methadone Maintenance Treatment among Drug Users with HIV/AIDS

    OpenAIRE

    Bach Xuan Tran; Arto Ohinmaa; Steve Mills; Anh Thuy Duong; Long Thanh Nguyen; Philip Jacobs; Stan Houston

    2012-01-01

    BACKGROUND: Ongoing drug use during methadone maintenance treatment (MMT) negatively affects outcomes of HIV/AIDS care and treatment for drug users. This study assessed changes in opioid use, and longitudinal predictors of continued opioid use during MMT among HIV-positive drug users in Vietnam, with the aim of identifying changes that might enhance program efficacy. METHODS: We analyze data of 370 HIV-positive drug users (mean age 29.5; 95.7% male) taking MMT at multi-sites. Opioid use was a...

  20. Spreadsheet based teaching aids in chemical engineering education

    OpenAIRE

    Heyen, Georges; Kalitventzeff, Boris

    1999-01-01

    Modern spreadsheet programs offer a wide range of calculation, charting and dialog options, allowing the development of effective teaching aids. Examples of worksheet illustrating numerical analysis, thermodynamics and unit operations are shown. All offer complete interaction between the problem statement and the presentation of results. Peer reviewed

  1. Caesy: A software tool for computer-aided engineering

    Science.gov (United States)

    Wette, Matt

    1993-01-01

    A new software tool, Caesy, is described. This tool provides a strongly typed programming environment for research in the development of algorithms and software for computer-aided control system design. A description of the user language and its implementation as they currently stand are presented along with a description of work in progress and areas of future work.

  2. Barriers to the Uptake of Concurrent Engineering in the Nigerian Construction Industry

    Directory of Open Access Journals (Sweden)

    Nathaniel Anny Aniekwu

    2012-12-01

    engineering and also to compute the Kendall’s coefficient of concordance, which assess the levels of agreement among the judges on the consistency of the rankings. A Kendall’s coefficient of concordance of W=0.57365 was recorded. A lack of awareness emerged as the most important barrier against the integration of this concept into the Nigerian construction industry. The top five variables are all human factors that can be ameliorated by proper education.

  3. 14 CFR 121.333 - Supplemental oxygen for emergency descent and for first aid; turbine engine powered airplanes...

    Science.gov (United States)

    2010-01-01

    ... and for first aid; turbine engine powered airplanes with pressurized cabins. 121.333 Section 121.333... for emergency descent and for first aid; turbine engine powered airplanes with pressurized cabins. (a) General. When operating a turbine engine powered airplane with a pressurized cabin, the certificate...

  4. Concurrent System Engineering and Risk Reduction for Dual-Band (RF/optical) Spacecraft Communications

    Science.gov (United States)

    Fielhauer, Karl, B.; Boone, Bradley, G.; Raible, Daniel, E.

    2012-01-01

    This paper describes a system engineering approach to examining the potential for combining elements of a deep-space RF and optical communications payload, for the purpose of reducing the size, weight and power burden on the spacecraft and the mission. Figures of merit and analytical methodologies are discussed to conduct trade studies, and several potential technology integration strategies are presented. Finally, the NASA Integrated Radio and Optical Communications (iROC) project is described, which directly addresses the combined RF and optical approach.

  5. Holographic aids for internal combustion engine flow studies

    Science.gov (United States)

    Regan, C.

    1984-01-01

    Worldwide interest in improving the fuel efficiency of internal combustion (I.C.) engines has sparked research efforts designed to learn more about the flow processes of these engines. The flow fields must be understood prior to fuel injection in order to design efficient valves, piston geometries, and fuel injectors. Knowledge of the flow field is also necessary to determine the heat transfer to combustion chamber surfaces. Computational codes can predict velocity and turbulence patterns, but experimental verification is mandatory to justify their basic assumptions. Due to their nonintrusive nature, optical methods are ideally suited to provide the necessary velocity verification data. Optical sytems such as Schlieren photography, laser velocimetry, and illuminated particle visualization are used in I.C. engines, and now their versatility is improved by employing holography. These holographically enhanced optical techniques are described with emphasis on their applications in I.C. engines.

  6. The effect of computer-aided detection markers on visual search and reader performance during concurrent reading of CT colonography

    Energy Technology Data Exchange (ETDEWEB)

    Helbren, Emma; Taylor, Stuart A. [University College London, Centre for Medical Imaging, London (United Kingdom); Fanshawe, Thomas R.; Mallett, Susan [University of Oxford, Nuffield Department of Primary Care Health Sciences, Oxford (United Kingdom); Phillips, Peter [University of Cumbria, Health and Medical Sciences Group, Lancaster (United Kingdom); Boone, Darren [Colchester Hospital University NHS Foundation Trust and Anglia University, Colchester (United Kingdom); Gale, Alastair [Loughborough University, Applied Vision Research Centre, Loughborough (United Kingdom); Altman, Douglas G. [University of Oxford, Centre for Statistics in Medicine, Oxford (United Kingdom); Manning, David [Lancaster University, Lancaster Medical School, Faculty of Health and Medicine, Lancaster (United Kingdom); Halligan, Steve [University College London, Centre for Medical Imaging, London (United Kingdom); University College Hospital, Gastrointestinal Radiology, University College London, Centre for Medical Imaging, Podium Level 2, London, NW1 2BU (United Kingdom)

    2015-06-01

    We aimed to identify the effect of computer-aided detection (CAD) on visual search and performance in CT Colonography (CTC) of inexperienced and experienced readers. Fifteen endoluminal CTC examinations were recorded, each with one polyp, and two videos were generated, one with and one without a CAD mark. Forty-two readers (17 experienced, 25 inexperienced) interpreted the videos during infrared visual search recording. CAD markers and polyps were treated as regions of interest in data processing. This multi-reader, multi-case study was analysed using multilevel modelling. CAD drew readers' attention to polyps faster, accelerating identification times: median 'time to first pursuit' was 0.48 s (IQR 0.27 to 0.87 s) with CAD, versus 0.58 s (IQR 0.35 to 1.06 s) without. For inexperienced readers, CAD also held visual attention for longer. All visual search metrics used to assess visual gaze behaviour demonstrated statistically significant differences when ''with'' and ''without'' CAD were compared. A significant increase in the number of correct polyp identifications across all readers was seen with CAD (74 % without CAD, 87 % with CAD; p < 0.001). CAD significantly alters visual search and polyp identification in readers viewing three-dimensional endoluminal CTC. For polyp and CAD marker pursuit times, CAD generally exerted a larger effect on inexperienced readers. (orig.)

  7. The effect of computer-aided detection markers on visual search and reader performance during concurrent reading of CT colonography

    International Nuclear Information System (INIS)

    We aimed to identify the effect of computer-aided detection (CAD) on visual search and performance in CT Colonography (CTC) of inexperienced and experienced readers. Fifteen endoluminal CTC examinations were recorded, each with one polyp, and two videos were generated, one with and one without a CAD mark. Forty-two readers (17 experienced, 25 inexperienced) interpreted the videos during infrared visual search recording. CAD markers and polyps were treated as regions of interest in data processing. This multi-reader, multi-case study was analysed using multilevel modelling. CAD drew readers' attention to polyps faster, accelerating identification times: median 'time to first pursuit' was 0.48 s (IQR 0.27 to 0.87 s) with CAD, versus 0.58 s (IQR 0.35 to 1.06 s) without. For inexperienced readers, CAD also held visual attention for longer. All visual search metrics used to assess visual gaze behaviour demonstrated statistically significant differences when ''with'' and ''without'' CAD were compared. A significant increase in the number of correct polyp identifications across all readers was seen with CAD (74 % without CAD, 87 % with CAD; p < 0.001). CAD significantly alters visual search and polyp identification in readers viewing three-dimensional endoluminal CTC. For polyp and CAD marker pursuit times, CAD generally exerted a larger effect on inexperienced readers. (orig.)

  8. Computer-Aided System of Virtual Testing of Gas Turbine Engines

    Directory of Open Access Journals (Sweden)

    Rybakov Viktor N.

    2016-01-01

    Full Text Available The article describes the concept of a virtual lab that includes subsystem of gas turbine engine simulation, subsystem of experiment planning, subsystem of measurement errors simulation, subsystem of simulator identification and others. The basis for virtual lab development is the computer-aided system of thermogasdynamic research and analysis “ASTRA”. The features of gas turbine engine transient modes simulator are described. The principal difference between the simulators of transient and stationary modes of gas turbine engines is that the energy balance of the compressor and turbine becomes not applicable. The computer-aided system of virtual gas turbine engine testing was created using the developed transient modes simulator. This system solves the tasks of operational (throttling, speed, climatic, altitude characteristics calculation, analysis of transient dynamics and selection of optimal control laws. Besides, the system of virtual gas turbine engine testing is a clear demonstration of gas turbine engine working process and the regularities of engine elements collaboration. The interface of the system of virtual gas turbine engine testing is described in the article and some screenshots of the interface elements are provided. The developed system of virtual gas turbine engine testing provides means for reducing the laboriousness of gas turbine engines testing. Besides, the implementation of this system in the learning process allows the diversification of lab works and therefore improve the quality of training.

  9. Multilevel predictors of concurrent opioid use during methadone maintenance treatment among drug users with HIV/AIDS.

    Directory of Open Access Journals (Sweden)

    Bach Xuan Tran

    Full Text Available BACKGROUND: Ongoing drug use during methadone maintenance treatment (MMT negatively affects outcomes of HIV/AIDS care and treatment for drug users. This study assessed changes in opioid use, and longitudinal predictors of continued opioid use during MMT among HIV-positive drug users in Vietnam, with the aim of identifying changes that might enhance program efficacy. METHODS: We analyze data of 370 HIV-positive drug users (mean age 29.5; 95.7% male taking MMT at multi-sites. Opioid use was assessed at baseline, 3, 6, and 9 months using interviews and heroin confirmatory urine tests. A social ecological model was applied to explore multilevel predictors of continued opioid use, including individual, interpersonal, community and service influences. Generalized estimating equations (GEE statistical models were constructed to adjust for intra-individual correlations. RESULTS: Over 9 month follow-up, self-reported opioid use and positive heroin urine test substantially decreased to 14.6% and 14.4%. MMT helped improve referrals and access to health care and social services. However, utilization of social integration services was small. GEE models determined that participants who were older (Adjusted Odd Ratio - AOR = 0.97 for 1 year increase, had economic dependents (AOR = 0.33, or were referred to TB treatment (AOR = 0.53 were less likely to continue opioid use. Significant positive predictors of ongoing opioid use included frequency of opioid use prior to MMT, peer pressure, living with sexual partners, taking antiretroviral treatment, other health concerns and TB treatment. CONCLUSION: These findings show that MMT in the Vietnamese context can dramatically reduce opioid use, which is known to be associated with reduced antiretroviral (ART adherence. Disease stage and drug interactions between antiretrovirals or TB drugs and MMT could explain some of the observed predictors of ongoing drug use; these findings could inform changes in MMT

  10. CONCURRENT ENGINEERING MODEL (CEM ANALYSIS ON LOGISTICS DESIGN PARAMETERS – A CASE STUDY

    Directory of Open Access Journals (Sweden)

    J.S. Gnanasekaran

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: Logistics engineering can be divided into internal or in-plant logistics and external manufacturing logistics. Internal (in-plant logistics include material handling, warehousing, and storage systems, while external manufacturing logistics include transportation. Both must be integrated to minimise costs at a competitive level of service. For example, plant layout and production planning must consider internal logistics. The design decisions are made in the early phases of product design, and development will have a significant effect over future manufacturing and logistical activities. In this paper, a methodology is developed and presented to minimise the design cycle time of any manufacturing firm, including their suppliers, and to maximise the whole system’s effectiveness.

    AFRIKAANSE OPSOMMING: Logistieke ingenieurswese kan verdeel word in interne of binne-aanleg logistiek en eksterne vervaardigingslogistiek. Interne (binne-aanleg logistiek behels materiaalhantering, berging en voorraadhoudingsisteme, terwyl eksterne vervaardigingslogistiek vervoer insluit. Die fasette moet geintegreer wees om koste te minimiseer by ‘n mededingende diensvlak. So byvoorbeeld moet die uitleg van ‘n aanleg en produksiebeplanning interne logistiek in aanmerking neem. Die ontwerpbesluite word geneem in die beginstadium van die produkontwerp en ontwikkeling sal ‘n betekenisvolle invloed hê op toekomstige vervaardigings- en logistieke aktiwiteite. In hierdie artikel word ‘n metodologie ontwikkel en aangebied om die ontwerpsiklustyd van enige vervaardigingsonderneming te minimiseer met inagneming van die leweransiers om sodoende die totale sisteem se effektiwiteit te maksimiseer.

  11. Data management for Computer-Aided Engineering (CAE)

    Science.gov (United States)

    Bryant, W. A.; Smith, M. R.

    1984-01-01

    Analysis of data flow through the design and manufacturing processes has established specific information management requirements and identified unique problems. The application of data management technology to the engineering/manufacturing environment addresses these problems. An overview of the IPAD prototype data base management system, representing a partial solution to these problems, is presented here.

  12. Reverse and concurrent engineering applied of a high resolution equipment Berkut for 1-meter class telescopes

    Science.gov (United States)

    López, R.; Granados, R.; Farah, A.

    2014-07-01

    Several factors make observational astronomy difficult for astronomers; one of them is the atmosphere. The light that a star emits is refracted when it goes through the earth's atmosphere; the result of this is that the image of a punctual star is not what the physics would lead us to expect. At the Instituto de Astronomia of the Universidad Nacional Autonoma de México (IA-UNAM) an instrument has been developed called "Berkut", which uses a high resolution technique to improve these effects and obtain interesting and valuable scientific studies. In this paper we present the mechanical reengineering and acceptance test of Berkut. This instrument was design for taking images of high resolution. Essentially, it is composed by a set basic optics which is aligned and in focus with a 1- meter class telescope. It has its own electronic components for controlling remotely a filter wheel; that allows the exchange of the filters according to the requirements of the observer, a couple of objectives mounted in a translation stage, and a CCD camera for acquiring several images per second that are used in the speckle interferometry technique. A project like Berkut needs to be multidisciplinary; astronomy, engineering, optics, mechanics, electronics, and image processing are some of the areas of knowledge used. Berkut will be used in the telescope of the Observatorio Astronomico Nacional in Tonantzintla, located in the state of Puebla, Mexico, but it can be used in any telescope 1 meter class. It is pretended to build another Berkuts for being used simultaneously in different telescopes, so it is important to keep the costs as low as possible. With this instrument we pretend to confirm the Hipparcos catalogue of binary stars besides finding exoplanets.

  13. 并行工程冲突管理总论%Conflict Management in Concurrent Engineering

    Institute of Scientific and Technical Information of China (English)

    徐文胜; 熊光楞; 钟佩思

    2001-01-01

    It is an important requirement of Concurrent Engineering(CE) to manage conflicts effectively and comprehensively. CE conflict management is not only a simple resolution for conflicts, but also a kind of comprehensive coordination and management for CE product development process. Beginning by analyzing the characteristics of CE system and the origins of conflicts in CE, the concept of conflict management and the framework of research on conflict management in CE are proposed. The theory, key techniques and support tools of conflict management are analyzed.%明确指出了并行工程冲突管理的概念、内涵,提出并建立了并行工程冲突管理研究的体系框架。在该框架下结合并行工程理论与实践的需要,明确了冲突管理的研究方向;分析并确定了冲突管理要素的性质、结构,为冲突管理的实施提供了理由和依据;最后结合我们所做的研究工作提出并分析了冲突管理的关键支持技术,为冲突管理的有效实施提供了技术方法支持。

  14. Computer-Aided Multiscale Modelling for Chemical Process Engineering

    DEFF Research Database (Denmark)

    Morales Rodriguez, Ricardo; Gani, Rafiqul

    2007-01-01

    Chemical processes are generally modeled through monoscale approaches, which, while not adequate, satisfy a useful role in product-process design. In this case, use of a multi-dimensional and multi-scale model-based approach has importance in product-process development. A computer-aided framework......T) for model translation, analysis and solution. The integration of ModDev, MoT and ICAS or any other external software or process simulator (using COM-Objects) permits the generation of different models and/or process configurations for purposes of simulation, design and analysis. Consequently, it is possible...... for model generation, analysis, solution and implementation is necessary for the development and application of the desired model-based approach for product-centric process design/analysis. This goal is achieved through the combination of a system for model development (ModDev), and a modelling tool (Mo...

  15. Computer aided power flow software engineering and code generation

    Energy Technology Data Exchange (ETDEWEB)

    Bacher, R. [Swiss Federal Inst. of Tech., Zuerich (Switzerland)

    1996-02-01

    In this paper a software engineering concept is described which permits the automatic solution of a non-linear set of network equations. The power flow equation set can be seen as a defined subset of a network equation set. The automated solution process is the numerical Newton-Raphson solution process of the power flow equations where the key code parts are the numeric mismatch and the numeric Jacobian term computation. It is shown that both the Jacobian and the mismatch term source code can be automatically generated in a conventional language such as Fortran or C. Thereby one starts from a high level, symbolic language with automatic differentiation and code generation facilities. As a result of this software engineering process an efficient, very high quality newton-Raphson solution code is generated which allows easier implementation of network equation model enhancements and easier code maintenance as compared to hand-coded Fortran or C code.

  16. Computer aided power flow software engineering and code generation

    Energy Technology Data Exchange (ETDEWEB)

    Bacher, R. [Swiss Federal Inst. of Tech., Zuerich (Switzerland)

    1995-12-31

    In this paper a software engineering concept is described which permits the automatic solution of a non-linear set of network equations. The power flow equation set can be seen as a defined subset of a network equation set. The automated solution process is the numerical Newton-Raphson solution process of the power flow equations where the key code parts are the numeric mismatch and the numeric Jacobian term computation. It is shown that both the Jacobian and the mismatch term source code can be automatically generated in a conventional language such as Fortran or C. Thereby one starts from a high level, symbolic language with automatic differentiation and code generation facilities. As a result of this software engineering process an efficient, very high quality Newton-Raphson solution code is generated which allows easier implementation of network equation model enhancements and easier code maintenance as compared to hand-coded Fortran or C code.

  17. The ICT as a Teaching Aid in the Formation of Professional Competence Within Engineering Students

    OpenAIRE

    Gonzalo González Rey; Alejandra García Toll; María Eugenia García Domínguez

    2011-01-01

    In present days, the application of information and communication technologies (ICTs) in teaching processes has made great changes in engineering teaching. In this article, the possibilities that the application of ICTs offers in the educational process as a teaching aid are exposed. In the career of Mechanical Engineering during the courses of Machine Elements Design some ICTs application as a teaching medium are used in a systematic and consistent manner. After which, the impact of its appl...

  18. Human performance models for computer-aided engineering

    Science.gov (United States)

    Elkind, Jerome I. (Editor); Card, Stuart K. (Editor); Hochberg, Julian (Editor); Huey, Beverly Messick (Editor)

    1989-01-01

    This report discusses a topic important to the field of computational human factors: models of human performance and their use in computer-based engineering facilities for the design of complex systems. It focuses on a particular human factors design problem -- the design of cockpit systems for advanced helicopters -- and on a particular aspect of human performance -- vision and related cognitive functions. By focusing in this way, the authors were able to address the selected topics in some depth and develop findings and recommendations that they believe have application to many other aspects of human performance and to other design domains.

  19. Computer-aided modeling for efficient and innovative product-process engineering

    DEFF Research Database (Denmark)

    Heitzig, Martina

    Model-based computer aided product-process engineering has attained increased importance in a number of industries, including pharmaceuticals, petrochemicals, fine chemicals, polymers, biotechnology, food, energy and water. This trend is set to continue due to the substantial benefits computer......-aided methods provide. The key prerequisite of computer-aided productprocess engineering is however the availability of models of different types, forms and application modes. The development of the models required for the systems under investigation tends to be a challenging, time-consuming and therefore cost......-intensive task involving numerous steps, expert skills and different modelling tools. The objective of this project is to systematize the process of model development and application thereby increasing the efficiency of the modeller as well as model quality. The main contributions of this thesis are a generic...

  20. Integrated Computer Aided Planning and Manufacture of Advanced Technology Jet Engines

    Directory of Open Access Journals (Sweden)

    B. K. Subhas

    1987-10-01

    Full Text Available This paper highlights an attempt at evolving a computer aided manufacturing system on a personal computer. A case study of an advanced technology jet engine component is included to illustrate various outputs from the system. The proposed system could be an alternate solution to sophisticated and expensive CAD/CAM workstations.

  1. The ICT as a Teaching Aid in the Formation of Professional Competence Within Engineering Students

    Directory of Open Access Journals (Sweden)

    Gonzalo González Rey

    2011-10-01

    Full Text Available In present days, the application of information and communication technologies (ICTs in teaching processes has made great changes in engineering teaching. In this article, the possibilities that the application of ICTs offers in the educational process as a teaching aid are exposed. In the career of Mechanical Engineering during the courses of Machine Elements Design some ICTs application as a teaching medium are used in a systematic and consistent manner. After which, the impact of its application is evaluated with regard to the formation of professional competence within mechanical engineering students.

  2. Application of integrated computer-aided engineering for design, construction and operation of nuclear power plant

    International Nuclear Information System (INIS)

    Computer-aided-engineering (CAE) is an essential tool for modern nuclear power plant engineering. It greatly varies in definition, application, and technology from project to project and company to company. Despite the fast growing technologies and applications of CAE, its complexty and variety have thrown aonther puzzle to management of a nuclear project. Without due consideration of an integrated CAE system in early planning stage, the overall efficiency of a nuclear project would slow down due to the inefficiency in data flow. In this paper, practices and perspectives of CAE appliation are discussed under the Korea Power Engineering Company (KOPEC) philosophy in CAE approach. (author)

  3. Computer Aided Engineering of Cyber-Physical Information Gathering and Utilizing Systems

    Directory of Open Access Journals (Sweden)

    Alfred P. Defonzo

    2012-08-01

    Full Text Available Engineering Cyber-physical information gathering and utilizing systems(CIGUS presents the systems engineer with a difficult, multi-criterion, multi-objective decision problem. Research, development and design is done over many disciplines, across many domains, each with their specific models. Systems engineers are expected to provide a common level of communication amongst the domains to promote convergence to a design. We present novel information measures that enable combination of the underlying domain specific subsystems parameters in a way that makes the information yield of the system intelligible to decision makers and domain experts. These measures enable, for the first time, the application of multi-objective evolutionary algorithms and end-to-end computer aided engineering of CIGUS. Our novel approach is validated and verified through the application and direct comparison of simulated and experimental results of state-ofthe- art weather radar network test bed designs. The approach resulted in Pareto optimal point within an average of 10% of the actual case study design parameters and within 25% of the Pareto ideal point. No additional parameters beyond the underlying domain parameters were introduced. This demonstrates that the computationally aided engineering approach presented in this work facilitates engineering feasibility decisions and the subsequent evolution of the engineered systems in way that reduces cost and effort.

  4. A group decision-making method based on intuitionistic fuzzy set in the three dimensional concurrent engineering environment: a multi-objective programming approach

    OpenAIRE

    Shidpour, Hesam; Alain, Bernard; Shahrokhi, Mahmoud

    2013-01-01

    International audience This paper proposes a group decision-making process by using multi-objective programming to address three-dimensional concurrent engineering (3D-CE) problems involving product, process and supply chain design. This paper uses opinion of decision makers to evaluate of the candidate suppliers and to determine importance of criteria by considering lack knowledge/information in the early design stages. For identifying impact of the lack knowledge/information on selecting...

  5. Computer-Aided Software Engineering - An approach to real-time software development

    Science.gov (United States)

    Walker, Carrie K.; Turkovich, John J.

    1989-01-01

    A new software engineering discipline is Computer-Aided Software Engineering (CASE), a technology aimed at automating the software development process. This paper explores the development of CASE technology, particularly in the area of real-time/scientific/engineering software, and a history of CASE is given. The proposed software development environment for the Advanced Launch System (ALS CASE) is described as an example of an advanced software development system for real-time/scientific/engineering (RT/SE) software. The Automated Programming Subsystem of ALS CASE automatically generates executable code and corresponding documentation from a suitably formatted specification of the software requirements. Software requirements are interactively specified in the form of engineering block diagrams. Several demonstrations of the Automated Programming Subsystem are discussed.

  6. Second Asia-Pacific Conference on the Computer Aided System Engineering

    CERN Document Server

    Chaczko, Zenon; Jacak, Witold; Łuba, Tadeusz; Computational Intelligence and Efficiency in Engineering Systems

    2015-01-01

    This carefully edited and reviewed volume addresses the increasingly popular demand for seeking more clarity in the data that we are immersed in. It offers excellent examples of the intelligent ubiquitous computation, as well as recent advances in systems engineering and informatics. The content represents state-of-the-art foundations for researchers in the domain of modern computation, computer science, system engineering and networking, with many examples that are set in industrial application context. The book includes the carefully selected best contributions to APCASE 2014, the 2nd Asia-Pacific Conference on  Computer Aided System Engineering, held February 10-12, 2014 in South Kuta, Bali, Indonesia. The book consists of four main parts that cover data-oriented engineering science research in a wide range of applications: computational models and knowledge discovery; communications networks and cloud computing; computer-based systems; and data-oriented and software-intensive systems.

  7. Computer aided training in nuclear power engineering at the Gdansk Technical University

    International Nuclear Information System (INIS)

    The Faculty of Electrical Engineering of the Gdansk Technical University has organized post-graduate studies in nuclear power engineering in cooperation with the Institute of Nuclear Research at Swierk since 1973. Post-graduate courses in nuclear power plant construction and design were organized twice. Between 1986 and 1990, prototype software was developed for aiding lectures, self-teaching and knowledge testing in the following fields: 1) dynamics and control of nuclear reactors; 2) simulators of nuclear power plant basic systems (reactor, steam generator, steam turbine, and synchronous generator). (Z.S.) 2 refs

  8. Assess/Mitigate Risk through the Use of Computer-Aided Software Engineering (CASE) Tools

    Science.gov (United States)

    Aguilar, Michael L.

    2013-01-01

    The NASA Engineering and Safety Center (NESC) was requested to perform an independent assessment of the mitigation of the Constellation Program (CxP) Risk 4421 through the use of computer-aided software engineering (CASE) tools. With the cancellation of the CxP, the assessment goals were modified to capture lessons learned and best practices in the use of CASE tools. The assessment goal was to prepare the next program for the use of these CASE tools. The outcome of the assessment is contained in this document.

  9. Computer-aided-engineering system for modeling and analysis of ECLSS integration testing

    Science.gov (United States)

    Sepahban, Sonbol

    1987-01-01

    The accurate modeling and analysis of two-phase fluid networks found in environmental control and life support systems is presently undertaken by computer-aided engineering (CAE) techniques whose generalized fluid dynamics package can solve arbitrary flow networks. The CAE system for integrated test bed modeling and analysis will also furnish interfaces and subsystem/test-article mathematical models. Three-dimensional diagrams of the test bed are generated by the system after performing the requisite simulation and analysis.

  10. Basic Principles of Industrial Electric Power Network Computer Aided Design and Engineering

    Directory of Open Access Journals (Sweden)

    M. Fursanov

    2012-01-01

    Full Text Available A conceptual model for a computer aided design and engineering system has been developed in the paper. The paper presents basic automation process principles including a graphical representation   network and calculation results, convenient user interface, automatic mode calculation, selection of transformer rated power and cross-section area of wires. The developed algorithm and program make it possible to save time and improve quality of project implementation.

  11. A Concurrent Engineering Constraint Decomposition Method%一种并行工程约束分解方法

    Institute of Scientific and Technical Information of China (English)

    常天庆; 徐文胜; 熊光楞; 何健廉

    2001-01-01

    In Concurrent Engineering, complex problems involving complexconstraints are often met in the product development process. It is a general method that decomposing a big problem into some small sub-problems according to its structure characteristics and then obtaining the problem's solution through resolving the sub-problems. Actually, the sub-problems are not independent each other, so that general decomposition methods can only solve the problem partially. It is important to further decompose the relationship among the sub-problems so that optimal solutions can be got through resolving the sub-problems separately. To minimize couplings among sub-problems, couplings will be further decomposed during design process. New constraints are introduced and constraints on multiple variables are converted to constraints on each individual variable (a range of values). This kind of decomposition is called constraint decomposition. Constraint decomposition is necessary especially in conceptual design period. This paper gives the meaning of constraint decomposition and proposes a constraint-based optimal decomposition method. Constraint decomposition reduces the size of a big problem and lowers the degree of difficulty in searching for solutions. To facilitate constraint decomposition, the concepts of strong-satisfaction and strong-satisfaction variables are proposed, and the upper level and lower level of variables are defined. By our proposed constraint decomposition method, firstly, value ranges of variables in the upper level are derived by bottom-up approach. Then by limiting value ranges of variables in the lower level by top-down approach, strong-satisfaction is guaranteed for the lower level variables and Pareto solutions for the problem are achieved. The bottom-up and top-down modifications for constraints can guarantee strong-satisfaction and Pareto solutions for the problem.This constraint decomposition method is effective for propagating upper level function

  12. A Paper Presentation on Software Development Automation by Computer Aided Software Engineering (CASE

    Directory of Open Access Journals (Sweden)

    Nishant Dubey

    2011-01-01

    Full Text Available Nowadays, system developers are faced to produce complex, high quality software to support the demand for new and revised computer applications. This challenge is complicated by strict resource constraints, forcing management to deploy new technologies, methods and procedures to manage this increasingly complex environment. Often the methods, procedures and technologies are not integrated. Therefore, they achieve less than desired improvements in productivity, or force management to make tradeoff decisions between software quality and developer efficiency. Thus the production lines have to be developed faster, too. A very important role in this development is Software Engineering because many production processes are 'computer aided', so software has to be designed for this production system. It seems very important to do the software engineering right and fast.

  13. Design of computer integrated manufacturing and educational system using decision support system, and case base reasoning in concurrent engineering environment

    Directory of Open Access Journals (Sweden)

    2012-10-01

    Full Text Available The main objective of this paper is to address the concept and design of a computerintegrated manufacturing (CIM and intelligent educational system in concurrent engineeringenvironment for Saipa Automotive Industry in Iran. In order to increase speed of design andprocess planning and manufacturing, a feature based approach and case base reasoning technicfor acquiring design specification and compare with previously designed 'features and retrieverelated process planed and modify for new parts. In order to design and plan effectively, onemust have a view of how the enterprise works in CIM environment, and what informationneeds. In this paper we will discuss a general model, in terms of its functions, what each areadoes, and how each area interacts with the others. we will also discuss the support functions,administration, application development and decision support functions that are common toalmost every enterprise. We will also describe the architectural requirements for implementinga computer integrated manufacturing strategy in computer based concurrent engineeringenvironment and how this architecture can support the entire enterprise in terms of itsfunctional, information resource and organizational needs.

  14. Flexible structure control experiments using a real-time workstation for computer-aided control engineering

    Science.gov (United States)

    Stieber, Michael E.

    1989-01-01

    A Real-Time Workstation for Computer-Aided Control Engineering has been developed jointly by the Communications Research Centre (CRC) and Ruhr-Universitaet Bochum (RUB), West Germany. The system is presently used for the development and experimental verification of control techniques for large space systems with significant structural flexibility. The Real-Time Workstation essentially is an implementation of RUB's extensive Computer-Aided Control Engineering package KEDDC on an INTEL micro-computer running under the RMS real-time operating system. The portable system supports system identification, analysis, control design and simulation, as well as the immediate implementation and test of control systems. The Real-Time Workstation is currently being used by CRC to study control/structure interaction on a ground-based structure called DAISY, whose design was inspired by a reflector antenna. DAISY emulates the dynamics of a large flexible spacecraft with the following characteristics: rigid body modes, many clustered vibration modes with low frequencies and extremely low damping. The Real-Time Workstation was found to be a very powerful tool for experimental studies, supporting control design and simulation, and conducting and evaluating tests withn one integrated environment.

  15. Retention of Students in Engineering. A Report to the Legislature in Response to Senate Concurrent Resolution 16 (1985).

    Science.gov (United States)

    California State Postsecondary Education Commission, Sacramento.

    In 1985, the California legislature directed the California Postsecondary Education Commission to study the attrition rate of students in engineering education in order to learn if ethnic minority and women students had a higher drop-out rate than all engineering students and, if so, to determine the reasons for their high attrition. In that…

  16. 并行工程工作方法在飞机研制中的应用%Application of Concurrent Engineering Methodology in Aircraft Development

    Institute of Scientific and Technical Information of China (English)

    曹凌云

    2012-01-01

    This paper aims at minding the organizers and the technicians to avoid misusing of concurrent engineering methodology in aircraft development. By describing the definition, connotative meanings and the actual practice result, the paper points out the issues to be eliminated and principles to be followed to make the program benefit and progress actually and efficiently.%描述了并行工程的定义、内涵及应用目标,结合飞机研制中采用并行工程时容易出现的问题,探讨了如何采取有效措施加以防范,使并行工程工作方法在飞机研制项目中更有效地发挥作用,旨在为管理者和技术人员提供参考。

  17. Evaluation of computer-aided software engineering tools for data base development

    Energy Technology Data Exchange (ETDEWEB)

    Woyna, M.A.; Carlson, C.R.

    1989-02-01

    More than 80 computer-aided software engineering (CASE) tools were evaluated to determine their usefulness in data base development projects. The goal was to review the current state of the CASE industry and recommend one or more tools for inclusion in the uniform development environment (UDE), a programming environment being designed by Argonne National Laboratory for the US Department of Defense Organization of the Joint Chiefs of Staff, J-8 Directorate. This environment gives a computer programmer a consistent user interface and access to a full suite of tools and utilities for software development. In an effort to identify tools that would be useful in the planning, analysis, design, implementation, and maintenance of Argonne's data base development projects for the J-8 Directorate, we evaluated 83 commercially available CASE products. This report outlines the method used and presents the results of the evaluation.

  18. Accelerating Development of EV Batteries Through Computer-Aided Engineering (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Pesaran, A.; Kim, G. H.; Smith, K.; Santhanagopalan, S.

    2012-12-01

    The Department of Energy's Vehicle Technology Program has launched the Computer-Aided Engineering for Automotive Batteries (CAEBAT) project to work with national labs, industry and software venders to develop sophisticated software. As coordinator, NREL has teamed with a number of companies to help improve and accelerate battery design and production. This presentation provides an overview of CAEBAT, including its predictive computer simulation of Li-ion batteries known as the Multi-Scale Multi-Dimensional (MSMD) model framework. MSMD's modular, flexible architecture connects the physics of battery charge/discharge processes, thermal control, safety and reliability in a computationally efficient manner. This allows independent development of submodels at the cell and pack levels.

  19. (Re)engineering Earth System Models to Expose Greater Concurrency for Ultrascale Computing: Practice, Experience, and Musings

    Science.gov (United States)

    Mills, R. T.

    2014-12-01

    As the high performance computing (HPC) community pushes towards the exascale horizon, the importance and prevalence of fine-grained parallelism in new computer architectures is increasing. This is perhaps most apparent in the proliferation of so-called "accelerators" such as the Intel Xeon Phi or NVIDIA GPGPUs, but the trend also holds for CPUs, where serial performance has grown slowly and effective use of hardware threads and vector units are becoming increasingly important to realizing high performance. This has significant implications for weather, climate, and Earth system modeling codes, many of which display impressive scalability across MPI ranks but take relatively little advantage of threading and vector processing. In addition to increasing parallelism, next generation codes will also need to address increasingly deep hierarchies for data movement: NUMA/cache levels, on node vs. off node, local vs. wide neighborhoods on the interconnect, and even in the I/O system. We will discuss some approaches (grounded in experiences with the Intel Xeon Phi architecture) for restructuring Earth science codes to maximize concurrency across multiple levels (vectors, threads, MPI ranks), and also discuss some novel approaches for minimizing expensive data movement/communication.

  20. Creating a strategic plan for configuration management using computer aided software engineering (CASE) tools

    International Nuclear Information System (INIS)

    This paper provides guidance in the definition, documentation, measurement, enhancement of processes, and validation of a strategic plan for configuration management (CM). The approach and methodology used in establishing a strategic plan is the same for any enterprise, including the Department of Energy (DOE), commercial nuclear plants, the Department of Defense (DOD), or large industrial complexes. The principles and techniques presented are used world wide by some of the largest corporations. The authors used industry knowledge and the areas of their current employment to illustrate and provide examples. Developing a strategic configuration and information management plan for DOE Idaho Field Office (DOE-ID) facilities is discussed in this paper. A good knowledge of CM principles is the key to successful strategic planning. This paper will describe and define CM elements, and discuss how CM integrates the facility's physical configuration, design basis, and documentation. The strategic plan does not need the support of a computer aided software engineering (CASE) tool. However, the use of the CASE tool provides a methodology for consistency in approach, graphics, and database capability combined to form an encyclopedia and a method of presentation that is easily understood and aids the process of reengineering. CASE tools have much more capability than those stated above. Some examples are supporting a joint application development group (JAD) to prepare a software functional specification document and, if necessary, provide the capability to automatically generate software application code. This paper briefly discusses characteristics and capabilities of two CASE tools that use different methodologies to generate similar deliverables

  1. Taking Advantage of the Model: Application of the Quantity, Units, Dimension, and Values Standard in Concurrent Spacecraft Engineering

    OpenAIRE

    Schaus, Volker; Fischer, Philipp M.; Gerndt, Andreas

    2013-01-01

    Designing a spacecraft involves many experts from different domains. In the early design phases they are brought together to discuss the spacecraft in a short period of time. The elements and building blocks the individual engineers want to use are stored and described in a shared system model provided by a software framework. A lot of features like the masses or dimensions are described using parameters. Due to the various domains and individual preference, many different units are used, lea...

  2. Accelerating Design of Batteries Using Computer-Aided Engineering Tools (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Pesaran, A.; Kim, G. H.; Smith, K.

    2010-11-01

    Computer-aided engineering (CAE) is a proven pathway, especially in the automotive industry, to improve performance by resolving the relevant physics in complex systems, shortening the product development design cycle, thus reducing cost, and providing an efficient way to evaluate parameters for robust designs. Academic models include the relevant physics details, but neglect engineering complexities. Industry models include the relevant macroscopic geometry and system conditions, but simplify the fundamental physics too much. Most of the CAE battery tools for in-house use are custom model codes and require expert users. There is a need to make these battery modeling and design tools more accessible to end users such as battery developers, pack integrators, and vehicle makers. Developing integrated and physics-based CAE battery tools can reduce the design, build, test, break, re-design, re-build, and re-test cycle and help lower costs. NREL has been involved in developing various models to predict the thermal and electrochemical performance of large-format cells and has used in commercial three-dimensional finite-element analysis and computational fluid dynamics to study battery pack thermal issues. These NREL cell and pack design tools can be integrated to help support the automotive industry and to accelerate battery design.

  3. A systematic framework for computer-aided design of engineering rubber formulations

    Science.gov (United States)

    Ghosh, Prasenjeet

    This thesis considers the design of engineering rubber formulations, whose unique properties of elasticity and resilience enable diverse applications. Engineering rubber formulations are a complex mixture of different materials called curatives that includes elastomers, fillers, crosslinking agents, accelerators, activators, retarders, anti-oxidants and processing aids, where the amount of curatives must be adjusted for each application. The characterization of the final properties of the rubber in application is complex and depends on the chemical interplay between the different curatives in formulation via vulcanization chemistry. The details of the processing conditions and the thermal, deformational, and chemical environment encountered in application also have a pronounced effect on the performance of the rubber. Consequently, for much of the history of rubber as an engineering material, its recipe formulations have been developed largely by trial-and-error, rather than by a fundamental understanding. A computer-aided, systematic and automated framework for the design of such materials is proposed in this thesis. The framework requires the solution to two sub-problems: (a) the forward problem, which involves prediction of the desired properties when the formulation is known and (b) the inverse problem that requires identification of the appropriate formulation, given the desired target properties. As part of the forward model, the chemistry of accelerated sulfur vulcanization is reviewed that permits integration of the knowledge of the past five decades in the literature to answer some old questions, reconcile some of the contradicting mechanisms and present a holistic description of the governing chemistry. Based on this mechanistic chemistry, a fundamental kinetic model is derived using population balance equations. The model quantitatively describes, for the first time, the different aspects of vulcanization chemistry. Subsequently, a novel three

  4. A Study of the Use of Ontologies for Building Computer-Aided Control Engineering Self-Learning Educational Software

    Science.gov (United States)

    García, Isaías; Benavides, Carmen; Alaiz, Héctor; Alonso, Angel

    2013-01-01

    This paper describes research on the use of knowledge models (ontologies) for building computer-aided educational software in the field of control engineering. Ontologies are able to represent in the computer a very rich conceptual model of a given domain. This model can be used later for a number of purposes in different software applications. In…

  5. Application of integrated computer-aided engineering for design, construction and operation of nuclear power plant: practice and prospects

    International Nuclear Information System (INIS)

    Computer-aided-engineering (CAE) is an essential tool for modern nuclear power plant engineering. It greatly varies in definition, application, and technology from project to project and company to company. Despite the fast growing technologies and applications of CAE, its complexity and variety have thrown another puzzle to management of a nuclear project. Without due consideration of an integrated CAE system in early planning stage, the overall efficiency of a nuclear project would slow down due to the inefficiency in data flow. In this application are discussed under the Korea Power engineering Company philosophy in CAE approach

  6. Creating a strategic plan for configuration management using computer aided software engineering (CASE) tools

    Energy Technology Data Exchange (ETDEWEB)

    Smith, P.R.; Sarfaty, R.

    1993-05-01

    This paper provides guidance in the definition, documentation, measurement, enhancement of processes, and validation of a strategic plan for configuration management (CM). The approach and methodology used in establishing a strategic plan is the same for any enterprise, including the Department of Energy (DOE), commercial nuclear plants, the Department of Defense (DOD), or large industrial complexes. The principles and techniques presented are used world wide by some of the largest corporations. The authors used industry knowledge and the areas of their current employment to illustrate and provide examples. Developing a strategic configuration and information management plan for DOE Idaho Field Office (DOE-ID) facilities is discussed in this paper. A good knowledge of CM principles is the key to successful strategic planning. This paper will describe and define CM elements, and discuss how CM integrates the facility`s physical configuration, design basis, and documentation. The strategic plan does not need the support of a computer aided software engineering (CASE) tool. However, the use of the CASE tool provides a methodology for consistency in approach, graphics, and database capability combined to form an encyclopedia and a method of presentation that is easily understood and aids the process of reengineering. CASE tools have much more capability than those stated above. Some examples are supporting a joint application development group (JAD) to prepare a software functional specification document and, if necessary, provide the capability to automatically generate software application code. This paper briefly discusses characteristics and capabilities of two CASE tools that use different methodologies to generate similar deliverables.

  7. The integration of automated knowledge acquisition with computer-aided software engineering for space shuttle expert systems

    Science.gov (United States)

    Modesitt, Kenneth L.

    1990-01-01

    A prediction was made that the terms expert systems and knowledge acquisition would begin to disappear over the next several years. This is not because they are falling into disuse; it is rather that practitioners are realizing that they are valuable adjuncts to software engineering, in terms of problem domains addressed, user acceptance, and in development methodologies. A specific problem was discussed, that of constructing an automated test analysis system for the Space Shuttle Main Engine. In this domain, knowledge acquisition was part of requirements systems analysis, and was performed with the aid of a powerful inductive ESBT in conjunction with a computer aided software engineering (CASE) tool. The original prediction is not a very risky one -- it has already been accomplished.

  8. Scientists Grow Therapeutic Protein in Engineered Soya Bean Seeds to Prevent AIDS | Poster

    Science.gov (United States)

    Genetically modified soya beans provide a scalable, low-cost method of producing microbicides that prevent AIDS, a technique sustainable for resource-poor countries where AIDS is spreading rapidly. According to the Joint United Nations Programme on HIV/AIDS, more than 36 million people worldwide are living with HIV. While the number of AIDS-related deaths are decreasing, infection rates are still increasing, specifically in Eastern and Southern Africa.

  9. Analytical Design Package (ADP2): A computer aided engineering tool for aircraft transparency design

    Science.gov (United States)

    Wuerer, J. E.; Gran, M.; Held, T. W.

    1994-01-01

    The Analytical Design Package (ADP2) is being developed as a part of the Air Force Frameless Transparency Program (FTP). ADP2 is an integrated design tool consisting of existing analysis codes and Computer Aided Engineering (CAE) software. The objective of the ADP2 is to develop and confirm an integrated design methodology for frameless transparencies, related aircraft interfaces, and their corresponding tooling. The application of this methodology will generate high confidence for achieving a qualified part prior to mold fabrication. ADP2 is a customized integration of analysis codes, CAE software, and material databases. The primary CAE integration tool for the ADP2 is P3/PATRAN, a commercial-off-the-shelf (COTS) software tool. The open architecture of P3/PATRAN allows customized installations with different applications modules for specific site requirements. Integration of material databases allows the engineer to select a material, and those material properties are automatically called into the relevant analysis code. The ADP2 materials database will be composed of four independent schemas: CAE Design, Processing, Testing, and Logistics Support. The design of ADP2 places major emphasis on the seamless integration of CAE and analysis modules with a single intuitive graphical interface. This tool is being designed to serve and be used by an entire project team, i.e., analysts, designers, materials experts, and managers. The final version of the software will be delivered to the Air Force in Jan. 1994. The Analytical Design Package (ADP2) will then be ready for transfer to industry. The package will be capable of a wide range of design and manufacturing applications.

  10. Concurrent partnerships and HIV: an inconvenient truth

    Directory of Open Access Journals (Sweden)

    Epstein Helen

    2011-03-01

    Full Text Available Abstract The strength of the evidence linking concurrency to HIV epidemic severity in southern and eastern Africa led the Joint United Nations Programme on HIV/AIDS and the Southern African Development Community in 2006 to conclude that high rates of concurrent sexual partnerships, combined with low rates of male circumcision and infrequent condom use, are major drivers of the AIDS epidemic in southern Africa. In a recent article in the Journal of the International AIDS Society, Larry Sawers and Eileen Stillwaggon attempt to challenge the evidence for the importance of concurrency and call for an end to research on the topic. However, their "systematic review of the evidence" is not an accurate summary of the research on concurrent partnerships and HIV, and it contains factual errors concerning the measurement and mathematical modelling of concurrency. Practical prevention-oriented research on concurrency is only just beginning. Most interventions to raise awareness about the risks of concurrency are less than two years old; few evaluations and no randomized-controlled trials of these programmes have been conducted. Determining whether these interventions can help people better assess their own risks and take steps to reduce them remains an important task for research. This kind of research is indeed the only way to obtain conclusive evidence on the role of concurrency, the programmes needed for effective prevention, the willingness of people to change behaviour, and the obstacles to change.

  11. Computer-aided design in power engineering. Application of software tools

    International Nuclear Information System (INIS)

    Demonstrates the use software tools in the practice of design in the field of power systems. Presents many applications in the design in the field of power systems. Useful for educative purposes and practical work. This textbooks demonstrates the application of software tools in solving a series of problems from the field of designing power system structures and systems. It contains four chapters: The first chapter leads the reader through all the phases necessary in the procedures of computer aided modeling and simulation. It guides through the complex problems presenting on the basis of eleven original examples. The second chapter presents application of software tools in power system calculations of power systems equipment design. Several design example calculations are carried out using engineering standards like MATLAB, EMTP/ATP, Excel and Access, AutoCAD and Simulink. The third chapters focuses on the graphical documentation using a collection of software tools (AutoCAD, EPLAN, SIMARIS SIVACON, SIMARIS DESIGN) which enable the complete automation of the development of graphical documentation of a power systems. In the fourth chapter, the application of software tools in the project management in power systems is discussed. Here, the emphasis is put on the standard software MS Excel and MS Project.

  12. Computer-aided design in power engineering. Application of software tools

    Energy Technology Data Exchange (ETDEWEB)

    Stojkovic, Zlatan

    2012-07-01

    Demonstrates the use software tools in the practice of design in the field of power systems. Presents many applications in the design in the field of power systems. Useful for educative purposes and practical work. This textbooks demonstrates the application of software tools in solving a series of problems from the field of designing power system structures and systems. It contains four chapters: The first chapter leads the reader through all the phases necessary in the procedures of computer aided modeling and simulation. It guides through the complex problems presenting on the basis of eleven original examples. The second chapter presents application of software tools in power system calculations of power systems equipment design. Several design example calculations are carried out using engineering standards like MATLAB, EMTP/ATP, Excel and Access, AutoCAD and Simulink. The third chapters focuses on the graphical documentation using a collection of software tools (AutoCAD, EPLAN, SIMARIS SIVACON, SIMARIS DESIGN) which enable the complete automation of the development of graphical documentation of a power systems. In the fourth chapter, the application of software tools in the project management in power systems is discussed. Here, the emphasis is put on the standard software MS Excel and MS Project.

  13. Development of computer-aided software engineering tool for sequential control of JT-60U

    Energy Technology Data Exchange (ETDEWEB)

    Shimono, M.; Akasaka, H.; Kurihara, K.; Kimura, T. [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    1995-12-31

    Discharge sequential control (DSC) is an essential control function for the intermittent and pulse discharge operation of a tokamak device, so that many subsystems may work with each other in correct order and/or synchronously. In the development of the DSC program, block diagrams of logical operation for sequential control are illustrated in its design at first. Then, the logical operators and I/O`s which are involved in the block diagrams are compiled and converted to a certain particular form. Since the block diagrams of the sequential control amounts to about 50 sheets in the case of the JT-60 upgrade tokamak (JT-60U) high power discharge and the above steps of the development have been performed manually so far, a great effort has been required for the program development. In order to remove inefficiency in such development processes, a computer-aided software engineering (CASE) tool has been developed on a UNIX workstation. This paper reports how the authors design it for the development of the sequential control programs. The tool is composed of the following three tools: (1) Automatic drawing tool, (2) Editing tool, and (3) Trace tool. This CASE tool, an object-oriented programming tool having graphical formalism, can powerfully accelerate the cycle for the development of the sequential control function commonly associated with pulse discharge in a tokamak fusion device.

  14. Computers in engineering 1983; Proceedings of the International Conference and Exhibit, Chicago, IL, August 7-11, 1983. Volume 1 - Computer-aided design, manufacturing, and simulation

    Science.gov (United States)

    Cokonis, T. J.

    The papers presented in this volume provide examples of the impact of computers on present engineering practice and indicate some future trends in computer-aided design, manufacturing, and simulation. Topics discussed include computer-aided design of turbine cycle configuration, managing and development of engineering computer systems, computer-aided manufacturing with robots in the automotive industry, and computer-aided design/analysis techniques of composite materials in the cure phase. Papers are also presented on computer simulation of vehicular propulsion systems, the performance of a hydraulic system simulator in a CAD environment, and computer simulation of hovercraft heave dynamics and control.

  15. Computer-Aided Protein Directed Evolution: a Review of Web Servers, Databases and other Computational Tools for Protein Engineering

    OpenAIRE

    Rajni Verma; Ulrich Schwaneberg; Danilo Roccatano

    2012-01-01

    The combination of computational and directed evolution methods has proven a winning strategy for protein engineering. We refer to this approach as computer-aided protein directed evolution (CAPDE) and the review summarizes the recent developments in this rapidly growing field. We will restrict ourselves to overview the availability, usability and limitations of web servers, databases and other computational tools proposed in the last five years. The goal of this review is to provide concise ...

  16. An Analysis of Computer Aided Design (CAD) Packages Used at MSFC for the Recent Initiative to Integrate Engineering Activities

    Science.gov (United States)

    Smith, Leigh M.; Parker, Nelson C. (Technical Monitor)

    2002-01-01

    This paper analyzes the use of Computer Aided Design (CAD) packages at NASA's Marshall Space Flight Center (MSFC). It examines the effectiveness of recent efforts to standardize CAD practices across MSFC engineering activities. An assessment of the roles played by management, designers, analysts, and manufacturers in this initiative will be explored. Finally, solutions are presented for better integration of CAD across MSFC in the future.

  17. Computer-Aided System Engineering and Analysis (CASE/A) Programmer's Manual, Version 5.0

    Science.gov (United States)

    Knox, J. C.

    1996-01-01

    The Computer Aided System Engineering and Analysis (CASE/A) Version 5.0 Programmer's Manual provides the programmer and user with information regarding the internal structure of the CASE/A 5.0 software system. CASE/A 5.0 is a trade study tool that provides modeling/simulation capabilities for analyzing environmental control and life support systems and active thermal control systems. CASE/A has been successfully used in studies such as the evaluation of carbon dioxide removal in the space station. CASE/A modeling provides a graphical and command-driven interface for the user. This interface allows the user to construct a model by placing equipment components in a graphical layout of the system hardware, then connect the components via flow streams and define their operating parameters. Once the equipment is placed, the simulation time and other control parameters can be set to run the simulation based on the model constructed. After completion of the simulation, graphical plots or text files can be obtained for evaluation of the simulation results over time. Additionally, users have the capability to control the simulation and extract information at various times in the simulation (e.g., control equipment operating parameters over the simulation time or extract plot data) by using "User Operations (OPS) Code." This OPS code is written in FORTRAN with a canned set of utility subroutines for performing common tasks. CASE/A version 5.0 software runs under the VAX VMS(Trademark) environment. It utilizes the Tektronics 4014(Trademark) graphics display system and the VTIOO(Trademark) text manipulation/display system.

  18. Teaching Computer-Aided Design of Fluid Flow and Heat Transfer Engineering Equipment.

    Science.gov (United States)

    Gosman, A. D.; And Others

    1979-01-01

    Describes a teaching program for fluid mechanics and heat transfer which contains both computer aided learning (CAL) and computer aided design (CAD) components and argues that the understanding of the physical and numerical modeling taught in the CAL course is essential to the proper implementation of CAD. (Author/CMV)

  19. Concurrent engineering in small companies

    OpenAIRE

    Starbek, Marko; Grum, Janez

    2015-01-01

    In 1991, attainment of independence in Slovenia caused a drastic decrease in domestic market for Slovenian companies. The companies which did not adapt to the new market conditions were destined for ruin. In this time several smaller companies were established which could adapt to new market conditions easier. When these companies entered the world market they encountered several difficulties such as excessive flow times for development of new products. After a survey of available literature ...

  20. NEXUS/NASCAD- NASA ENGINEERING EXTENDIBLE UNIFIED SOFTWARE SYSTEM WITH NASA COMPUTER AIDED DESIGN

    Science.gov (United States)

    Purves, L. R.

    1994-01-01

    NEXUS, the NASA Engineering Extendible Unified Software system, is a research set of computer programs designed to support the full sequence of activities encountered in NASA engineering projects. This sequence spans preliminary design, design analysis, detailed design, manufacturing, assembly, and testing. NEXUS primarily addresses the process of prototype engineering, the task of getting a single or small number of copies of a product to work. Prototype engineering is a critical element of large scale industrial production. The time and cost needed to introduce a new product are heavily dependent on two factors: 1) how efficiently required product prototypes can be developed, and 2) how efficiently required production facilities, also a prototype engineering development, can be completed. NEXUS extendibility and unification are achieved by organizing the system as an arbitrarily large set of computer programs accessed in a common manner through a standard user interface. The NEXUS interface is a multipurpose interactive graphics interface called NASCAD (NASA Computer Aided Design). NASCAD can be used to build and display two and three-dimensional geometries, to annotate models with dimension lines, text strings, etc., and to store and retrieve design related information such as names, masses, and power requirements of components used in the design. From the user's standpoint, NASCAD allows the construction, viewing, modification, and other processing of data structures that represent the design. Four basic types of data structures are supported by NASCAD: 1) three-dimensional geometric models of the object being designed, 2) alphanumeric arrays to hold data ranging from numeric scalars to multidimensional arrays of numbers or characters, 3) tabular data sets that provide a relational data base capability, and 4) procedure definitions to combine groups of system commands or other user procedures to create more powerful functions. NASCAD has extensive abilities to

  1. Extended precision data types for the development of the original computer aided engineering applications

    Science.gov (United States)

    Pescaru, A.; Oanta, E.; Axinte, T.; Dascalescu, A.-D.

    2015-11-01

    Computer aided engineering is based on models of the phenomena which are expressed as algorithms. The implementations of the algorithms are usually software applications which are processing a large volume of numerical data, regardless the size of the input data. In this way, the finite element method applications used to have an input data generator which was creating the entire volume of geometrical data, starting from the initial geometrical information and the parameters stored in the input data file. Moreover, there were several data processing stages, such as: renumbering of the nodes meant to minimize the size of the band length of the system of equations to be solved, computation of the equivalent nodal forces, computation of the element stiffness matrix, assemblation of system of equations, solving the system of equations, computation of the secondary variables. The modern software application use pre-processing and post-processing programs to easily handle the information. Beside this example, CAE applications use various stages of complex computation, being very interesting the accuracy of the final results. Along time, the development of CAE applications was a constant concern of the authors and the accuracy of the results was a very important target. The paper presents the various computing techniques which were imagined and implemented in the resulting applications: finite element method programs, finite difference element method programs, applied general numerical methods applications, data generators, graphical applications, experimental data reduction programs. In this context, the use of the extended precision data types was one of the solutions, the limitations being imposed by the size of the memory which may be allocated. To avoid the memory-related problems the data was stored in files. To minimize the execution time, part of the file was accessed using the dynamic memory allocation facilities. One of the most important consequences of the

  2. Computer aided engineering in exhaust aftertreatment systems design. Pt. 1. Spark ignition engine; Computergestuetzter Entwurf von Abgas-Nachbehandlungskonzepten. T. 1. Ottomotor

    Energy Technology Data Exchange (ETDEWEB)

    Stamatelos, A.M.; Koltsakis, G.C.; Kandylas, I.P. [Aristotelian Univ. of Thessaloniki (Greece)

    1999-02-01

    At the Aristotle University Thessaloniki, Greece, an integrated Computer Aided Engineering (CAE) methodology assisting the design of SI-engine exhaust aftertreatment systems employing the following computational tools was developed: A computer code which models transient exhaust system heat transfer, a tuneable computer code which models the transient operation of a three-way catalytic converter, a database containing chemical kinetics data for a variety of catalyst formulations, and a methodology for ageing assessment calculations. Application of the CAE methodology, which aids the exhaust aftertreatment system design engineer to meet the upcoming, increasingly stringent emission standards, is high-lighted by referring to a number of representative case studies. (orig.) [Deutsch] An der Aristoteles-Universitaet Thessaloniki, Griechenland, wurde eine computergestuetzte Methode (CAE) entwickelt, die den Entwurf und die Konstruktion von Abgasnachbehandlungskonzepten unterstuetzt. Die Methode setzt auf die folgenden Rechenmodelle und Datenbanken: Ein Rechenmodell zur Berechnung des Waermeuebergangs in Motorabgassystemen, ein Rechenmodell zur Abschaetzung des Katalysatorgegendrucks, eine Datenbank mit den chemischen Kinetikdaten fuer die verschiedenen Typen von Dreiwegekatalysatoren und eine computergestuetzte Prozedur zur Abschaetzung des Alterungsverhaltens von Dreiwegekatalysatoren. Integrierte CAE-Methoden koennen beim Entwurf von modernen Abgasnachbehandlungssystemen angewandt werden, um die Entwicklungszeit und -kosten betraechtlich zu reduzieren. (orig.)

  3. 并行工程中的三域原理及其体系结构研究%Three-Domain Principle Suggested for Concurrent Engineering (CE)

    Institute of Scientific and Technical Information of China (English)

    秦现生; 王润孝; 武子; 徐亚斌

    2001-01-01

    We deem that the study of CE (concurrent engineering) theory and CE technology as a whole has been very inadequate and thus handicaps the further development of CE. In section 2, we discuss in much detail our suggestion of three-domain principle for CE. The three domains are domain support, domain implementing and domain management. Domain support provides all the necessary support for CE implementing. Domain implementing considers all the activities of product-life-cycle. Domain management assures that the implementing of CE is by CE theory and method. Figs.1 and 2 taken together give the CE system structure based on three-domain principle. Fig.3 gives a CE spiral model, which is helpful to the better planning of all activities even though, in reality, in product-life-cycle, the activities are done in series, i.e., the last activity has just finished and the next activity is yet to begin.%针对CE的体系结构及其实施过程中的两类支持问题,通过对CE基本理论的研究,建立了以支撑域、执行域和管理域三域为基础的CE体系结构,使CE的实施不仅有一个基本的支持环境,而且从组织管理上确保其严格按CE的基本原理进行。为解决CE关于一体化、并行设计的组织管理问题,提出了CE的微观串行宏观并行原理,并建立了相应的CE螺旋模型。对基于三域原理的CE体系结构的应用如信息集成框架、面向Internet/Intranet的应用和实施以及与企业环境的融合也进行了研究。

  4. Low-Income Engineering Students: Considering Financial Aid and Differential Tuition

    Science.gov (United States)

    George-Jackson, Casey E.; Rincon, Blanca; Martinez, Mariana G.

    2012-01-01

    This paper explores the relationship between tuition differentials and low-income students in Engineering fields at two public, research-intensive universities. Although current reports indicate the need for increased participation within the Science, Technology, Engineering, and Mathematics (STEM) fields, rising tuition prices at the university…

  5. Basic Concurrency Theory

    DEFF Research Database (Denmark)

    Løvengreen, Hans Henrik

    2002-01-01

    In this set of notes, we present some of the basic theory underlying the discipline of programming with concurrent processes/threads. The notes are intended to supplement a standard textbook on concurrent programming.......In this set of notes, we present some of the basic theory underlying the discipline of programming with concurrent processes/threads. The notes are intended to supplement a standard textbook on concurrent programming....

  6. Concurrent weighted logic

    DEFF Research Database (Denmark)

    Xue, Bingtian; Larsen, Kim Guldstrand; Mardare, Radu Iulian

    2015-01-01

    We introduce Concurrent Weighted Logic (CWL), a multimodal logic for concurrent labeled weighted transition systems (LWSs). The synchronization of LWSs is described using dedicated functions that, in various concurrency paradigms, allow us to encode the compositionality of LWSs. To reflect these,...

  7. Computer-aided analysis and design of the shape rolling process for producing turbine engine airfoils

    Science.gov (United States)

    Lahoti, G. D.; Akgerman, N.; Altan, T.

    1978-01-01

    Mild steel (AISI 1018) was selected as model cold rolling material and Ti-6A1-4V and Inconel 718 were selected as typical hot rolling and cold rolling alloys, respectively. The flow stress and workability of these alloys were characterized and friction factor at the roll/workpiece interface was determined at their respective working conditions by conducting ring tests. Computer-aided mathematical models for predicting metal flow and stresses, and for simulating the shape rolling process were developed. These models utilized the upper bound and the slab methods of analysis, and were capable of predicting the lateral spread, roll separating force, roll torque, and local stresses, strains and strain rates. This computer-aided design system was also capable of simulating the actual rolling process, and thereby designing the roll pass schedule in rolling of an airfoil or a similar shape.

  8. Computer-Aided Design Methods for Model-Based Nonlinear Engine Control Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Traditional design methods for aircraft turbine engine control systems have relied on the use of linearized models and linear control theory. While these...

  9. CNG-diesel engine performance and exhaust emission analysis with the aid of artificial neural network

    Energy Technology Data Exchange (ETDEWEB)

    Yusaf, Talal F.; Buttsworth, D.R.; Saleh, Khalid H. [University of Southern Queensland, Faculty of Engineering and Surveying, Mechanical Engineering, Toowoomba, 4350 Queensland (Australia); Yousif, B.F. [Mechanical Department, Faculty of Engineering, University of Nottingham, Symenih (Malaysia)

    2010-05-15

    This study investigates the use of artificial neural network (ANN) modelling to predict brake power, torque, break specific fuel consumption (BSFC), and exhaust emissions of a diesel engine modified to operate with a combination of both compressed natural gas CNG and diesel fuels. A single cylinder, four-stroke diesel engine was modified for the present work and was operated at different engine loads and speeds. The experimental results reveal that the mixtures of CNG and diesel fuel provided better engine performance and improved the emission characteristics compared with the pure diesel fuel. For the ANN modelling, the standard back-propagation algorithm was found to be the optimum choice for training the model. A multi-layer perception network was used for non-linear mapping between the input and output parameters. It was found that the ANN model is able to predict the engine performance and exhaust emissions with a correlation coefficient of 0.9884, 0.9838, 0.95707, and 0.9934 for the engine torque, BSFC, NO{sub x} and exhaust temperature, respectively. (author)

  10. Constraints meet concurrency

    CERN Document Server

    Mauro, Jacopo

    2014-01-01

    This book describes the benefits that emerge when the fields of constraint programming and concurrency meet. On the one hand, constraints can be used in concurrency theory to increase the conciseness and the expressive power of concurrent languages from a pragmatic point of view. On the other hand, problems modeled by using constraints can be solved faster and more efficiently using a concurrent system. Both directions are explored providing two separate lines of development. Firstly the expressive power of a concurrent language is studied, namely Constraint Handling Rules, that supports constraints as a primitive construct. The features of this language which make it Turing powerful are shown. Then a framework is proposed to solve constraint problems that is intended to be deployed on a concurrent system. For the development of this framework the concurrent language Jolie following the Service Oriented paradigm is used. Based on this experience, an extension to Service Oriented Languages is also proposed in ...

  11. Computer aided modeling and simulation of hydroforming on tubular engineering products

    Directory of Open Access Journals (Sweden)

    Jeremy (Zheng Li

    2013-01-01

    Full Text Available Hydroforming processes have been widely applied in many different industrial fields including aerospace, automotive, and modern plastics for weight-reduction and strength enhancement. Hydroforming on tubular products is better than the process of welding tubular assemblies from stampings including increased strength, reduction of work applied to the unit weight, decreased processing and tool costs, improved structural stability, less secondary operation, enhanced stiffness, and more uniform in product thickness. Although the hydroforming becomes popular manufacturing methodology, few researches have been done to study the hydroforming mechanism through computational modeling and simulation. This paper focuses on the study of hydroforming process and mechanism based on computer-aided modeling (FEA and prototype testing to determine the material behaviors in hydroforming process. The objective of this research is to verify the effects of major manufacturing parameters on hydroforming processes. The computational analysis and prototype testing indicate that some factors including applied internal pressure path and compressive axial loading play important roles in hydroforming deformation. Both computer-aided modeling and prototyping experiment show close results which verifies the credibility of this research and analytic methodology.

  12. Methodology of Computer-Aided Design of Variable Guide Vanes of Aircraft Engines

    Science.gov (United States)

    Falaleev, Sergei V.; Melentjev, Vladimir S.; Gvozdev, Alexander S.

    2016-01-01

    The paper presents a methodology which helps to avoid a great amount of costly experimental research. This methodology includes thermo-gas dynamic design of an engine and its mounts, the profiling of compressor flow path and cascade design of guide vanes. Employing a method elaborated by Howell, we provide a theoretical solution to the task of…

  13. Research on Embedded Software Quality Control Method Based on Concurrent Engineering%基于并行工程的嵌入式软件质量控制方法的研究

    Institute of Scientific and Technical Information of China (English)

    代睿

    2014-01-01

    With the embedded technology is used widely in the electronic equipments, the quality supervision of the embedded software becomes more and more important. On the base of introducing the importance of software and the difficult point of the quality supervision of the embedded software, the embedded software test model based on concurrent engineering is proposed. And the concurrent engineering based developing method of the progress coding and test coding is discussed in the aim to enhance the quality control of software development so as to improve the quality of software.%随着嵌入式技术大量应用到电子设备中,嵌入式软件的质量监督检验日趋重要。本文在阐述软件质量的重要性和嵌入式软件质量监督的难点的基础上,提出了基于并行工程的嵌入式软件测试模型和编码阶段的程序代码与测试代码并行开发的方法,旨在加强软件开发过程的质量控制,从而提高软件的质量。

  14. The Benefits and Its Implementation of Concurrent Engineering in Commercial Aircraft Development Program%并行工程在商用飞机研发项目中的益处及其实施方法

    Institute of Scientific and Technical Information of China (English)

    于海燕

    2015-01-01

    使用较少经费和较短时间研发出质量优越的商用飞机是各飞机研发团队的共同目标. 阐述了通过使用科学的方法和管理技术,例如并行工程,是商用飞机研发项目达成上述目标的途径之一,介绍了一种具备可操作性的实施并行工程的方法.%It is the ultimate goal for commercial aircraft design team to develop a commercial aircraft with out-standing quality while spending less and completing in a shorter time. This paper describes how to achieve such goals via scientific methods and management techniques like concurrent engineering in commercial aircraft develop-ment programs. In the end, a feasible approach to implement concurrent engineering is also briefly introduced.

  15. Temporal Concurrent Constraint Programming

    DEFF Research Database (Denmark)

    Nielsen, Mogens; Palamidessi, Catuscia; Valencia, Frank Dan

    2002-01-01

    The ntcc calculus is a model of non-deterministic temporal concurrent constraint programming. In this paper we study behavioral notions for this calculus. In the underlying computational model, concurrent constraint processes are executed in discrete time intervals. The behavioral notions studied...... reflect the reactive interactions between concurrent constraint processes and their environment, as well as internal interactions between individual processes. Relationships between the suggested notions are studied, and they are all proved to be decidable for a substantial fragment of the calculus...

  16. Computer aided system for generating fuel shuffling configurations based on knowledge engineering

    International Nuclear Information System (INIS)

    In a PWR core, approximately 1/3 of the burned fuels are replaced by fresh fuels after about a year's operation. Reload cores are designed so as to minimize the radial power peaking factor under design requirements and some administrative constraints. The conventional way of generating an appropriate fuel loading pattern is a method of trial error, which is laborious and requires much computer time. A computer aided system has therefore been developed to speed up and make more efficient the determination of fuel shuffling configurations in reload cores. The system consists of a rule-base system employing artificial intelligence techniques, a pin-wise diffusion code and a feedback program based on fuel assembly power distributions. It was successfully applied to cores with only burnable poison rods, with gadolinium-dispersed fuels and also to cores employing low leakage fuel management strategy. (author)

  17. Computer aided system engineering and analysis (CASE/A) modeling package for ECLS systems - An overview

    Science.gov (United States)

    Dalee, Robert C.; Bacskay, Allen S.; Knox, James C.

    1990-01-01

    An overview of the CASE/A-ECLSS series modeling package is presented. CASE/A is an analytical tool that has supplied engineering productivity accomplishments during ECLSS design activities. A components verification program was performed to assure component modeling validity based on test data from the Phase II comparative test program completed at the Marshall Space Flight Center. An integrated plotting feature has been added to the program which allows the operator to analyze on-screen data trends or get hard copy plots from within the CASE/A operating environment. New command features in the areas of schematic, output, and model management, and component data editing have been incorporated to enhance the engineer's productivity during a modeling program.

  18. Development of the engineering design integration (EDIN) system: A computer aided design development

    Science.gov (United States)

    Glatt, C. R.; Hirsch, G. N.

    1977-01-01

    The EDIN (Engineering Design Integration) System which provides a collection of hardware and software, enabling the engineer to perform man-in-the-loop interactive evaluation of aerospace vehicle concepts, was considered. Study efforts were concentrated in the following areas: (1) integration of hardware with the Univac Exec 8 System; (2) development of interactive software for the EDIN System; (3) upgrading of the EDIN technology module library to an interactive status; (4) verification of the soundness of the developing EDIN System; (5) support of NASA in design analysis studies using the EDIN System; (6) provide training and documentation in the use of the EDIN System; and (7) provide an implementation plan for the next phase of development and recommendations for meeting long range objectives.

  19. Effectiveness of using CADD (Computer-Aided Design Drafting) to learn engineering design graphics

    Energy Technology Data Exchange (ETDEWEB)

    Bertoline, G.R.

    1987-01-01

    One commercial CADD software and one educational CADD software was compared to the use of traditional tools. Engineering-graphics students were divided into three groups. The control group used traditional tools for all their drawings. One experimental group used a commercial CADD software to supplement hand tools and one group used an educational CADD software to supplement traditional tools. These groups were then post-tested using a standardized drafting test. The main findings were: (1) There was no significant difference in the learning of engineering graphics as measured by the post-tests. Supplementing traditional tools with CADD is effective for teaching engineering design graphics. (2) Using CADD for detail drawings such as simple orthographic drawings, sections, and dimensions could be produced in approximately the same amount of time as using traditional tools. (3) It was found that the amount of time needed to solve descriptive geometry problems using CADD was prohibitive. The amount of time to solve some descriptive geometry problems was two or three times greater using CADD versus traditional tools.

  20. STRATEGY FOR IMPROVEMENT OF SAFETY AND EFFICIENCY OF COMPUTER-AIDED DESIGN ANALYSIS OF CIVIL ENGINEERING STRUCTURES ON THE BASIS OF THE SYSTEM APPROACH

    OpenAIRE

    Zaikin Vladimir Genrikhovich; Valuyskikh Viktor Petrovich

    2012-01-01

    The authors highlight three problems of the age of information technologies and proposes the strategy for their resolution in relation to the computer-aided design of civil engineering structures. The authors express their concerns in respect of globalization of software programmes designated for the analysis of civil engineering structures and employed outside of Russia. The problem of the poor quality of the input data has reached Russia. Lately, the rate of accidents of buildings and s...

  1. New Structural-Dynamics Module for Offshore Multimember Substructures within the Wind Turbine Computer-Aided Engineering Tool FAST: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Song, H.; Damiani, R.; Robertson, A.; Jonkman, J.

    2013-08-01

    FAST, developed by the National Renewable Energy Laboratory (NREL), is a computer-aided engineering (CAE) tool for aero-hydro-servo-elastic analysis of land-based and offshore wind turbines. This paper discusses recent upgrades made to FAST to enable loads simulations of offshore wind turbines with fixed-bottom, multimember support structures (e.g., jackets and tripods, which are commonly used in transitional-depth waters). The main theory and strategies for the implementation of the multimember substructure dynamics module (SubDyn) within the new FAST modularization framework are introduced. SubDyn relies on two main engineering schematizations: 1) a linear frame finite-element beam (LFEB) model and 2) a dynamics system reduction via Craig-Bampton's method. A jacket support structure and an offshore system consisting of a turbine atop a jacket substructure were simulated to test the SubDyn module and to preliminarily assess results against results from a commercial finite-element code.

  2. Integrated computer-aided design in automotive development development processes, geometric fundamentals, methods of CAD, knowledge-based engineering data management

    CERN Document Server

    Mario, Hirz; Gfrerrer, Anton; Lang, Johann

    2013-01-01

    The automotive industry faces constant pressure to reduce development costs and time while still increasing vehicle quality. To meet this challenge, engineers and researchers in both science and industry are developing effective strategies and flexible tools by enhancing and further integrating powerful, computer-aided design technology. This book provides a valuable overview of the development tools and methods of today and tomorrow. It is targeted not only towards professional project and design engineers, but also to students and to anyone who is interested in state-of-the-art computer-aided development. The book begins with an overview of automotive development processes and the principles of virtual product development. Focusing on computer-aided design, a comprehensive outline of the fundamentals of geometry representation provides a deeper insight into the mathematical techniques used to describe and model geometrical elements. The book then explores the link between the demands of integrated design pr...

  3. Probabilistic Concurrent Kleene Algebra

    Directory of Open Access Journals (Sweden)

    Annabelle McIver

    2013-06-01

    Full Text Available We provide an extension of concurrent Kleene algebras to account for probabilistic properties. The algebra yields a unified framework containing nondeterminism, concurrency and probability and is sound with respect to the set of probabilistic automata modulo probabilistic simulation. We use the resulting algebra to generalise the algebraic formulation of a variant of Jones' rely/guarantee calculus.

  4. NRC Reviewer Aid for Evaluating the Human Factors Engineering Aspects of Small Modular Reactors

    Energy Technology Data Exchange (ETDEWEB)

    OHara J. M.; Higgins, J.C.

    2012-01-13

    Small modular reactors (SMRs) are a promising approach to meeting future energy needs. Although the electrical output of an individual SMR is relatively small compared to that of typical commercial nuclear plants, they can be grouped to produce as much energy as a utility demands. Furthermore, SMRs can be used for other purposes, such as producing hydrogen and generating process heat. The design characteristics of many SMRs differ from those of current conventional plants and may require a distinct concept of operations (ConOps). The U.S. Nuclear Regulatory Commission (NRC) conducted research to examine the human factors engineering (HFE) and the operational aspects of SMRs. The research identified thirty potential human-performance issues that should be considered in the NRC's reviews of SMR designs and in future research activities. The purpose of this report is to support NRC HFE reviewers of SMR applications by identifying some of the questions that can be asked of applicants whose designs have characteristics identified in the issues. The questions for each issue were identified and organized based on the review elements and guidance contained in Chapter 18 of the Standard Review Plan (NUREG-0800), and the Human Factors Engineering Program Review Model (NUREG-0711).

  5. Computer-Aided Systems Engineering for Flight Research Projects Using a Workgroup Database

    Science.gov (United States)

    Mizukami, Masahi

    2004-01-01

    An online systems engineering tool for flight research projects has been developed through the use of a workgroup database. Capabilities are implemented for typical flight research systems engineering needs in document library, configuration control, hazard analysis, hardware database, requirements management, action item tracking, project team information, and technical performance metrics. Repetitive tasks are automated to reduce workload and errors. Current data and documents are instantly available online and can be worked on collaboratively. Existing forms and conventional processes are used, rather than inventing or changing processes to fit the tool. An integrated tool set offers advantages by automatically cross-referencing data, minimizing redundant data entry, and reducing the number of programs that must be learned. With a simplified approach, significant improvements are attained over existing capabilities for minimal cost. By using a workgroup-level database platform, personnel most directly involved in the project can develop, modify, and maintain the system, thereby saving time and money. As a pilot project, the system has been used to support an in-house flight experiment. Options are proposed for developing and deploying this type of tool on a more extensive basis.

  6. ANALYSIS AND RESEARCH OF COMPUTER-AIDED MODEL OF HIP JOINT BASED ON REVERSE ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    Hu Xin; Xi Juntong; Jin Ye; Gu Dongyun; Dai Kerong

    2003-01-01

    Former research work about the modeling of hip joint focus on the upper segment of femoral, and assumes the acetabulum cup is sphere concave, and the acetabulum prostheses is semisphere. A method of acquiring the point data on the surface of the hipbone using the reverse engineering technology is presented. After analyzing the acetabulum surface fitting error, a rotation ellipsoid CAD model is applied to fit the acetabulum surface, and then optimization technique is used to find the geometric parameters of the model. The fitting error between the sphere and rotation ellipsoid is compared and gets the result that the fitting error of rotation ellipsoid is smaller than sphere, and the rotation ellipsoid can describe the shape of the acetabulum better.

  7. CFD aided optimization of an innovative SCR catalyst design for heavy-duty marine diesel engines

    Science.gov (United States)

    Krastev, V. K.; Russo, S.; Verdemare, D.; Recine, G.; Biferale, L.; Falcucci, G.

    2016-06-01

    In this paper, the design of a new system for reducing NOx from exhaust gases from marine engines is shown. The core of the system is represented by the Selective Catalytic Reduction (SCR) reactor, in which the catalyst is made of titanium dioxide nano-fibers functionalized with metal oxides and deposited by electrospinning on a corrugated metal support. Compared to the current monolithic reactor designs, the high specific surface offered by the fibers allows in principle to satisfy the TIER III emission standards, with a consistent saving in the reactor volume. To optimize the reactor design process, a Computational Fluid Dynamics (CFD) model has been developed, alongside experimental measurements and numerical simulations. Results of different configurations are reported and critically assessed.

  8. Biphasic electrical field stimulation aids in tissue engineering of multicell-type cardiac organoids.

    Science.gov (United States)

    Chiu, Loraine L Y; Iyer, Rohin K; King, John-Paul; Radisic, Milica

    2011-06-01

    The main objectives of current work were (1) to compare the effects of monophasic or biphasic electrical field stimulation on structure and function of engineered cardiac organoids based on enriched cardiomyocytes (CM) and (2) to determine if electrical field stimulation will enhance electrical excitability of cardiac organoids based on multiple cell types. Organoids resembling cardiac myofibers were cultivated in Matrigel-coated microchannels fabricated of poly(ethylene glycol)-diacrylate. We found that field stimulation using symmetric biphasic square pulses at 2.5 V/cm, 1 Hz, 1 ms (per pulse phase) was an improved stimulation protocol, as compared to no stimulation and stimulation using monophasic square pulses of identical total amplitude and duration (5 V/cm, 1 Hz, 2 ms). This was supported by the highest success rate for synchronous contractions, low excitation threshold, the highest cell density, and the highest expression of Connexin-43 in the biphasic group. Subsequently, enriched CM were seeded on the networks of (1) cardiac fibroblasts (FB), (2) D4T endothelial cells (EC), or (3) a mixture of FB and EC that were precultured for 2 days prior to the addition of enriched CM. Biphasic field stimulation was also effective at improving electrical excitability of these cardiac organoids by improving the three-dimensional organization of the cells, increasing cellular elongation and enhancing Connexin-43 presence.

  9. Computer-aided operations engineering with integrated models of systems and operations

    Science.gov (United States)

    Malin, Jane T.; Ryan, Dan; Fleming, Land

    1994-01-01

    CONFIG 3 is a prototype software tool that supports integrated conceptual design evaluation from early in the product life cycle, by supporting isolated or integrated modeling, simulation, and analysis of the function, structure, behavior, failures and operation of system designs. Integration and reuse of models is supported in an object-oriented environment providing capabilities for graph analysis and discrete event simulation. Integration is supported among diverse modeling approaches (component view, configuration or flow path view, and procedure view) and diverse simulation and analysis approaches. Support is provided for integrated engineering in diverse design domains, including mechanical and electro-mechanical systems, distributed computer systems, and chemical processing and transport systems. CONFIG supports abstracted qualitative and symbolic modeling, for early conceptual design. System models are component structure models with operating modes, with embedded time-related behavior models. CONFIG supports failure modeling and modeling of state or configuration changes that result in dynamic changes in dependencies among components. Operations and procedure models are activity structure models that interact with system models. CONFIG is designed to support evaluation of system operability, diagnosability and fault tolerance, and analysis of the development of system effects of problems over time, including faults, failures, and procedural or environmental difficulties.

  10. Specification of Concurrent Objects

    DEFF Research Database (Denmark)

    Sørensen, Morten U.

    Concurrent objects are named concurrent processes that interact by invoking each other's operations. We describe how such concurrent objects can be specified, how objects can be composed, and how it can be shown that one object refines another.First a model is defined, based on a transition...... relation over two objects and an event. In the model, objects can be composed by parallel composition, encapsulation, and hiding of operations. Refinement between objects is defined as fair trace inclusion.A specification language is presented where objects can be specified operationally by abstract...

  11. Computer aided engineering in exhaust aftertreatment sytems design. Part 2: Diesel engines; Computergestuetzter Entwurf von Abgas-Nachbehandlungskonzepten. Teil 2: Dieselmotoren

    Energy Technology Data Exchange (ETDEWEB)

    Stamatelos, A.M.; Koltsakis, G.C.; Kandylas, I.P. [Aristoteles Univ., Thessaloniki (Greece)

    1999-03-01

    In the field of diesel engines, there is growing interest in CAE methods for low-emission concepts, as newly developed mathematical models become more and more efficient. The design of diesel exhaust systems must take three general concepts into account: the oxidation catalyst, the particulate filter and the DeNO{sub x} catalyst. A CAE methodology developed at the Aristotle University in Thessaloniki, Greece, to aid engineers in designing exhaust systems is presented in this paper. The methodology is based on the following computational tools: a transient exhaust system heat transfer code, a transient oxidation and DeNO{sub x} catalytic converter code, a catalyst kinetics database for the various types of oxidation and DeNO{sub x} catalytic converters and a computational tool for calculating the loading and regeneration of diesel filters with and without catalytic support. (orig.) [Deutsch] Im Bereich der Dieselmotoren nimmt das Interesse an computergestuetzten CAE-Methoden fuer Niedrigemissionskonzepte zu, da neu entwickelte mathematische Modelle immer leistungsfaehiger werden. Der Entwurf von Dieselabgassystemen muss drei allgemeine Konzepte beruecksichtigen: Oxidationskatalysator, Partikelfilter und DeNO{sub x}-Katalysator. Eine an der Aristoteles Universitaet Thessaloniki, Griechenland, entwickelte computergestuetzte Methode, die den Entwurf von Abgassystemen unterstuetzten kann, wird im Folgenden dargestellt. Die Methode basiert auf folgenden Rechenmodellen: ein Modell zur Berechnung des Waermeuebergangs im Abgassystem, ein Rechenmodell zur Bestimmung des Instationaerverhaltens des Oxidations- und des DeNO{sub x}-Katalysators, eine Datenbank mit den chemischen Kinetikdaten fuer die verschiedenen Typen von Oxidations- und DeNO{sub x}-Katalysatoren sowie ein Rechenmodell zur Berechnung der Beladung und Regenerierung von Dieselfiltern mit oder ohne katalytische Unterstuetzung. (orig.)

  12. CASE/A - COMPUTER AIDED SYSTEM ENGINEERING AND ANALYSIS, ECLSS/ATCS SERIES

    Science.gov (United States)

    Bacskay, A.

    1994-01-01

    Design and analysis of Environmental Control and Life Support Systems (ECLSS) and Active Thermal Control Systems (ATCS) for spacecraft missions requires powerful software that is flexible and responsive to the demands of particular projects. CASE/A is an interactive trade study and analysis tool designed to increase productivity during all phases of systems engineering. The graphics-based command-driven package provides a user-friendly environment in which the engineer can analyze the performance and interface characteristics of an ECLS/ATC system. The package is useful during all phases of a spacecraft design program, from initial conceptual design trade studies to the actual flight, including pre-flight prediction and in-flight anomaly analysis. The CASE/A program consists of three fundamental parts: 1) the schematic management system, 2) the database management system, and 3) the simulation control and execution system. The schematic management system allows the user to graphically construct a system model by arranging icons representing system components and connecting the components with physical fluid streams. Version 4.1 contains 51 fully coded and documented default component routines. New components can be added by the user through the "blackbox" component option. The database management system supports the storage and manipulation of component data, output data, and solution control data through interactive edit screens. The simulation control and execution system initiates and controls the iterative solution process, displaying time status and any necessary diagnostic messages. In addition to these primary functions, the program provides three other important functional areas: 1) model output management, 2) system utility commands, and 3) user operations logic capacity. The model output management system provides tabular and graphical output capability. Complete fluid constituent mass fraction and properties data (mass flow, pressure, temperature

  13. Materials science virtual laboratory as an example of the computer aid in materials engineering

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2007-10-01

    Full Text Available Purpose: The purpose of the presented article is to describe the material science virtual laboratory, which is an open scientific, investigative, simulating and didactic medium for the realization of the didactic and educational tasks performed by traditional and e-learning methods.Design/methodology/approach: The laboratory is an aggregate of testers and training simulators, placed in the virtual reality and created in various languages and the programming techniques, which represents the properties, functionality and manual principles of real equipment installed and accessible in the real laboratories of scientific universities.Findings: Application of the equipment, that is practically imperishable, cheap in exploitation and easy in the use certainty will encourage students and scientific workers to independent audits and experiments in situations, where the possibilities of their execution in the true investigative laboratory will be limited because of the high material costs, difficult access to real equipment or the possible risk of his damage.Practical implications: The use possibilities of the virtual laboratory are practically unrestricted; it can be a base for any studies, course or training programme. It is assumed, that the project of the laboratory as fully multimedial. The participants of this laboratory can e.g. investigate training experiments from the definite field of material engineering, give questions, pass tests, contact with lecturers and the different users of the laboratory and obviously on participate in his design and content.Originality/value: The project of the virtual laboratory corresponds with the global tendency for expand the investigative and academical centers about the possibilities of training and experiments performance with use of the virtual reality. This enriches the education programme of the new abilities reserved so far exclusively for effecting only on real equipment.

  14. Temporal Concurrent Constraint Programming

    DEFF Research Database (Denmark)

    Nielsen, Mogens; Valencia Posso, Frank Dan

    2002-01-01

    The ntcc calculus is a model of non-deterministic temporal concurrent constraint programming. In this paper we study behavioral notions for this calculus. In the underlying computational model, concurrent constraint processes are executed in discrete time intervals. The behavioral notions studied....... Furthermore, the expressive power of this fragment is illustrated by examples. Basic Research in Computer Science, Centre of the Danish National Research Foundation....

  15. Composing concurrent objects

    OpenAIRE

    Bergmans, Louis Marie Johannes

    1994-01-01

    Adopting the object-oriented paradigm for the development of large and complex software systems offers several advantages, of which increased extensibility and reusability are the most prominent ones. The object-oriented model is also quite suitable for modelling concurrent systems. However, it appears that extensibility and reusability of concurrent applications is far from trivial. In addition, very little attention has been paid by the conventional object-oriented development methodologies...

  16. STRATEGY FOR IMPROVEMENT OF SAFETY AND EFFICIENCY OF COMPUTER-AIDED DESIGN ANALYSIS OF CIVIL ENGINEERING STRUCTURES ON THE BASIS OF THE SYSTEM APPROACH

    Directory of Open Access Journals (Sweden)

    Zaikin Vladimir Genrikhovich

    2012-12-01

    Full Text Available The authors highlight three problems of the age of information technologies and proposes the strategy for their resolution in relation to the computer-aided design of civil engineering structures. The authors express their concerns in respect of globalization of software programmes designated for the analysis of civil engineering structures and employed outside of Russia. The problem of the poor quality of the input data has reached Russia. Lately, the rate of accidents of buildings and structures has been growing not only in Russia. Control over efficiency of design projects is hardly performed. This attitude should be changed. Development and introduction of CAD along with the application the efficient methods of projection of behaviour of building structures are in demand. Computer-aided calculations have the function of a logical nucleus, and they need proper control. The system approach to computer-aided calculations and technologies designated for the projection of accidents is formulated by the authors. Two tasks of the system approach and fundamentals of the strategy for its implementation are formulated. The study of cases of negative results of computer-aided design of engineering structures was performed and multi-component design patterns were developed. Conclusions concerning the results of researches aimed at regular and wide-scale implementation of the strategy fundamentals are formulated. Organizational and innovative actions concerning the projected behaviour of civil engineering structures proposed in the strategy are to facilitate: safety and reliability improvement of buildings and structures; saving of building materials and resources; improvement of labour efficiency of designers; modernization and improvement of accuracy of projected behaviour of buildings and building standards; closer ties between civil and building engineering researchers and construction companies; development of competitive environment to boost

  17. Channel's Concurrence and Quantum Teleportation

    Institute of Scientific and Technical Information of China (English)

    LING Yin-Sheng

    2005-01-01

    Concurrence can measure the entanglement property of a system. If the channel is a pure state, positive concurrence state can afford the good performance in the teleportation process. If the channel ia a mixed state, positive concurrence state cannot assure the good performance in the teleportation. The conditions of the positive concurrence and the quantum teleportation in the Heisenberg spin ring is derived.

  18. Channel's Concurrence and Quantum Teleportation

    International Nuclear Information System (INIS)

    Concurrence can measure the entanglement property of a system. If the channel is a pure state, positive concurrence state can afford the good performance in the teleportation process. If the channel ia a mixed state, positive concurrence state cannot assure the good performance in the teleportation. The conditions of the positive concurrence and the quantum teleportation in the Heisenberg spin ring is derived.

  19. Concurrency and network disassortativity.

    Science.gov (United States)

    Khor, Susan

    2010-01-01

    The relationship between a network's degree-degree correlation and a loose version of graph coloring is studied on networks with broad degree distributions. We find that, given similar conditions on the number of nodes, number of links, and clustering levels, fewer colors are needed to color disassortative than assortative networks. Since fewer colors create fewer independent sets, our finding implies that disassortative networks may have higher concurrency potential than assortative networks. This in turn suggests another reason for the disassortative mixing pattern observed in biological networks such as those of protein-protein interaction and gene regulation. In addition to the functional specificity and stability suggested by Maslov and Sneppen, a disassortative network topology may also enhance the ability of cells to perform crucial tasks concurrently. Hence, increased concurrency may also be a driving force in the evolution of biological networks. PMID:20586579

  20. Droit de la concurrence

    OpenAIRE

    2009-01-01

    Le critère de l’efficience est au cœur d’un changement de paradigme qui s’observe dans les réflexions sur la politique et le droit de la concurrence au sein de l’UE et qui se reflète dans cette « more economic approach » que préconise la Commission. Ce constat avait incité en 2004 le groupe de travail Concurrence du vénérable Verein für Socialpolitik à rassembler autour de cette thématique praticiens (gardiens de la concurrence, entreprises) et scientifiques de renom. Au fond, le concept d’ef...

  1. A VLSI Architecture for Concurrent Data Structures

    OpenAIRE

    Dally, William J.

    1986-01-01

    Concurrent data structures simplify the development of concurrent programs by encapsulating commonly used mechanisms for synchronization and communication into data structures. This thesis develops a notation for describing concurrent data structures, presents examples of concurrent data structures, and describes an architecture to support concurrent data structures. Concurrent Smalltalk (CST), a derivative of Smalltalk-80 with extensions for concurrency, is developed to describe concurre...

  2. Building Safe Concurrency Abstractions

    DEFF Research Database (Denmark)

    Madsen, Ole Lehrmann

    2014-01-01

    as well as programming, and we describe how this has had an impact on the design of the language. Although Beta supports the definition of high-level concurrency abstractions, the use of these rely on the discipline of the programmer as is the case for Java and other mainstream OO languages. We introduce...

  3. A Concurrent Logical Relation

    DEFF Research Database (Denmark)

    Birkedal, Lars; Sieczkowski, Filip; Thamsborg, Jacob Junker

    2012-01-01

    We present a logical relation for showing the correctness of program transformations based on a new type-and-effect system for a concurrent extension of an ML-like language with higher-order functions, higher-order store and dynamic memory allocation. We show how to use our model to verify a number...

  4. Algebraic topology and concurrency

    DEFF Research Database (Denmark)

    Fajstrup, Lisbeth; Raussen, Martin; Goubault, Eric

    2006-01-01

    We show in this article that some concepts from homotopy theory, in algebraic topology,are relevant for studying concurrent programs. We exhibit a natural semantics of semaphore programs, based on partially ordered topological spaces, which are studied up to “elastic deformation” or homotopy, giv...

  5. The Concurrent Language Aldwych

    OpenAIRE

    Huntbach, Matthew

    2000-01-01

    Aldwych is proposed as the foundation of a general purpose language for parallel applications. It works on a rule-based principle, and has aspects variously of concurrent functional, logic and object-oriented languages, yet it forms an integrated whole. It is intended to be applicable both for small-scale parallel programming, and for large-scale open systems.

  6. Composing concurrent objects

    NARCIS (Netherlands)

    Bergmans, Louis Marie Johannes

    1994-01-01

    Adopting the object-oriented paradigm for the development of large and complex software systems offers several advantages, of which increased extensibility and reusability are the most prominent ones. The object-oriented model is also quite suitable for modelling concurrent systems. However, it appe

  7. Evaluation of Concurrent Radiation, Temozolomide and ABT-888 Treatment Followed by Maintenance Therapy with Temozolomide and ABT-888 in a Genetically Engineered Glioblastoma Mouse Model

    Directory of Open Access Journals (Sweden)

    Benjamin Lemasson

    2016-02-01

    Full Text Available Despite the use of ionizing radiation (IR and temozolomide (TMZ, outcome for glioblastoma (GBM patients remains dismal. Poly (ADP-ribose polymerase (PARP is important in repair pathways for IR-induced DNA damage and TMZ-induced alkylation at N7-methylguanine and N3-methyldenine. However, optimized protocols for administration of PARP inhibitors have not been delineated. In this study, the PARP inhibitor ABT-888 was evaluated in combination with and compared to current standard-of-care in a genetically engineered mouse GBM model. Results demonstrated that concomitant TMZ/IR/ABT-888 with adjuvant TMZ/ABT-888 was more effective in inducing apoptosis and reducing proliferation with significant tumor growth delay and improved overall survival over concomitant TMZ/IR with adjuvant TMZ. Diffusion-weighted MRI, an early translatable response biomarker detected changes in tumors reflecting response at 1 day post TMZ/IR/ABT-888 treatment. This study provides strong scientific rationale for the development of an optimized dosing regimen for a PARP inhibitor with TMZ/IR for upfront treatment of GBM.

  8. Domain Theory for Concurrency

    DEFF Research Database (Denmark)

    Nygaard, Mikkel

    Concurrent computation can be given an abstract mathematical treatment very similar to that provided for sequential computation by domain theory and denotational semantics of Scott and Strachey. A simple domain theory for concurrency is presented. Based on a categorical model of linear logic...... of affine-linear logic. This language adds to HOPLA an interesting tensor operation at the price of linearity constraints on the occurrences of variables. The tensor can be understood as a juxtaposition of independent processes, and allows Affine HOPLA to encode processes of the kind found in treatments...... of nondeterministic dataflow. The domain theory can be generalised to presheaf models, providing a more refined treatment of nondeterministic branching and supporting notions of bisimulation. The operational semantics for HOPLA is guided by the idea that derivations of transitions in the operational semantics should...

  9. Concurrent semantics for structured design methods

    OpenAIRE

    Nixon, Patrick

    1996-01-01

    Also in Jelly, I., Gordon, I., & Groll, P. Software Engineering for Parallel and Distributed Systems. London: Chapman Hall. Design methods can be ambiguous due to di#11;erent interpretations of symbols or concepts. This paper presents a formal semantics for the Ward/Mellor Structured Analysis Method for Real Time systems. These semantics ensures that an unambiguous meaning can be attributed to a particular design. Speci#12;cally, it ensures that concurrent and real-time propert...

  10. Reliability Analysis of Concurrent Systems using LTSA

    OpenAIRE

    G.N. Rodrigues; Rosenblum, D S; Wolf, J

    2007-01-01

    The analysis for software dependability is considered an important task within the software engineering life cycle. However, it is often impossible to carry out this task due to the complexity of available tools, lack of expert personnel and time-to-market pressures. As a result, released software versions may present unverified dependability properties subjecting customers to blind software reliability assessment. In particular, concurrent systems present certain behaviour that require a mor...

  11. Concurrent Software Testing : A Systematic Review and an Evaluation of Static Analysis Tools

    OpenAIRE

    Mamun, Md. Abdullah al; Khanam, Aklima

    2009-01-01

    Verification and validation is one of the most important concerns in the area of software engineering towards more reliable software development. Hence it is important to overcome the challenges of testing concurrent programs. The extensive use of concurrent systems warrants more attention to the concurrent software testing. For testing concurrent software, automatic tools development is getting increased focus. The first part of this study presents a systematic review that aims to explore th...

  12. Combustion Analysis of a CI Engine Performance Using Waste Cooking Biodiesel Fuel with an Artificial Neural Network Aid

    OpenAIRE

    Gholamhassan NAJAFI; Ghobadian, Barat; Talal F. YUSAF; Hadi RAHIMI

    2007-01-01

    A comprehensive combustion analysis has been conducted to evaluate the performance of a commercial DI engine, water cooled two cylinders, in-line, naturally aspirated, RD270 Ruggerini diesel engine using waste vegetable cooking oil as an alternative fuel. In order to compare the brake power and the torques values of the engine, it has been tested under same operating conditions with diesel fuel and waste cooking biodiesel fuel blends. The results were found to be very comparable. The properti...

  13. [Symptomatic and concurrent depressions].

    Science.gov (United States)

    Terra, J L

    1999-04-01

    The symptomatic and concurrent depressions description need to resort to comorbidity and symptomatic co-occurrence concepts. Patients with depressive symptoms or in a major depressive episode may also be suffering from another nonmood psychiatric disorders as alcoholism, anxiety or eating disorders. Many general medical conditions which are link with depression are illustrated with the examples of cancer, coronary artery disease, endocrinologic diseases, dementia, stroke and chronic fatigue syndrome. When depression and another psychiatric or medical conditions occur together, it is important to provide to the practitioner guidelines for the decision to treat one of the two disorders. This paper contains an example of decisional algorithm. PMID:10337217

  14. Morse Theory and Concurrency

    DEFF Research Database (Denmark)

    Wisniewski, Rafal

    2003-01-01

    The work is intended to provide some insight about concurrency theory using ideas from geometry and algebraic topology. We define a topological space containing all traces of execution of the computer program and the information about how time flows. This is the main difference with standard...... topological reasoning in which there is no information about relation "in time" among points. The main task is to define equivalence of paths reflecting execution of a program. We use the notion of homotopy history equivalence relation. The model space considered in this work is a differentiable manifold...

  15. Characterization of concurrent processing

    Science.gov (United States)

    Utku, S.; Melosh, R.; Salama, M.

    1985-01-01

    Computer architectures designed for concurrent processing are characterized by the number of processing elements, ensemble speed, random access memory, input/output routes, and modes of operation. The important attributes of processing tasks are then identified, and some processing stratagems are examined. It is shown that the greater the complexity of a given task, the wider the range of possible stratagems which can accomplish the task. For relatively simple tasks, the optimum stratagem can be found by analytical reasoning. For more complex tasks, however, optimum scheduling techniques may have to be employed for the assignment of segments of the task to the available processing elements.

  16. Mastering concurrency in Go

    CERN Document Server

    Kozyra, Nathan

    2014-01-01

    A practical approach covering everything you need to know to get up and running with Go, starting with the basics and imparting increasingly more detail as the examples and topics become more complicated. The book utilizes a casual, conversational style, rife with actual code and historical anecdotes for perspective, as well as usable and extensible example applications. This book is intended for systems developers and programmers with some experience in either Go and/or concurrent programming who wish to become fluent in building high-performance applications that scale by leveraging single-c

  17. Morse Theory and Concurrency

    DEFF Research Database (Denmark)

    Wisniewski, Rafal

    2003-01-01

    topological reasoning in which there is no information about relation "in time" among points. The main task is to define equivalence of paths reflecting execution of a program. We use the notion of homotopy history equivalence relation. The model space considered in this work is a differentiable manifold......The work is intended to provide some insight about concurrency theory using ideas from geometry and algebraic topology. We define a topological space containing all traces of execution of the computer program and the information about how time flows. This is the main difference with standard...

  18. Concurrent engineering design and management knowledge capture

    Science.gov (United States)

    1990-01-01

    The topics are presented in viewgraph form and include the following: real-time management, personnel management, project management, conceptual design and decision making; the SITRF design problem; and the electronic-design notebook.

  19. Assessing the Value-Added by the Environmental Testing Process with the Aide of Physics/Engineering of Failure Evaluations

    Science.gov (United States)

    Cornford, S.; Gibbel, M.

    1997-01-01

    NASA's Code QT Test Effectiveness Program is funding a series of applied research activities focused on utilizing the principles of physics and engineering of failure and those of engineering economics to assess and improve the value-added by the various validation and verification activities to organizations.

  20. Demonstrating the Usefulness of CAELinux for Computer Aided Engineering using an Example of the Three Dimensional Reconstruction of a Pig Liver

    CERN Document Server

    P., Kirana Kumara

    2012-01-01

    CAELinux is a Linux distribution which is bundled with free software packages related to Computer Aided Engineering (CAE). The free software packages include software that can build a three dimensional solid model, programs that can mesh a geometry, software for carrying out Finite Element Analysis (FEA), programs that can carry out image processing etc. Present work has two goals: 1) To give a brief description of CAELinux 2) To demonstrate that CAELinux could be useful for Computer Aided Engineering, using an example of the three dimensional reconstruction of a pig liver from a stack of CT-scan images. One can note that instead of using CAELinux, using commercial software for reconstructing the liver would cost a lot of money. One can also note that CAELinux is a free and open source operating system and all software packages that are included in the operating system are also free. Hence one can conclude that CAELinux could be a very useful tool in application areas like surgical simulation which require th...

  1. Recursive Concurrent Stochastic Games

    CERN Document Server

    Etessami, Kousha

    2008-01-01

    We study Recursive Concurrent Stochastic Games (RCSGs), extending our recent analysis of recursive simple stochastic games [16,17] to a concurrent setting where the two players choose moves simultaneously and independently at each state. For multi-exit games, our earlier work already showed undecidability for basic questions like termination, thus we focus on the important case of single-exit RCSGs (1-RCSGs). We first characterize the value of a 1-RCSG termination game as the least fixed point solution of a system of nonlinear minimax functional equations, and use it to show PSPACE decidability for the quantitative termination problem. We then give a strategy improvement technique, which we use to show that player 1 (maximizer) has \\epsilon-optimal randomized Stackless & Memoryless (r-SM) strategies for all \\epsilon > 0, while player 2 (minimizer) has optimal r-SM strategies. Thus, such games are r-SM-determined. These results mirror and generalize in a strong sense the randomized memoryless determinacy r...

  2. Information Technology Model for Product Lifecycle Engineering

    Directory of Open Access Journals (Sweden)

    Bhanumathi KS

    2013-02-01

    Full Text Available An aircraft is a complex, multi-disciplinary, system-engineered product that requires real-time global technical collaboration through its life-cycle. Engineering data and processes which form the backbone of the aircraft should be under strict Configuration Control (CC. It should be model-based and allow for 3D visualization and manipulation. This requires accurate, realtime collaboration and concurrent engineering-based business processes operating in an Integrated Digital Environment (IDE. The IDE uses lightweight, neutral Computer Aided Design (CAD Digital Mock-Up (DMU. The DMU deals with complex structural assemblies and systems of more than a hundred thousand parts created by engineers across the globe, each using diverse CAD, Computer Aided Engineering (CAE, Computer Aided Manufacturing (CAM, Computer Integrated Manufacturing (CIM, Enterprise Resource Planning (ERP, Supply Chain Management(SCM,Customer Relationship Management(CRM and Computer Aided Maintenance Management System (CAMMS systems. In this paper, a comprehensive approach to making such an environment a reality is presented.

  3. A concurrent design approach and model management support to prevent inconsistencies in multidisciplinary modelling and simulation

    NARCIS (Netherlands)

    Zhang, Xiaochen; Broenink, Jan F.

    2013-01-01

    Cyber-physical systems are multidisciplinary systems which involve different engineering disciplines in their design. Each engineering discipline tends to use its own domain-specific languages and tools to model different aspects of a system concurrently. The concurrent modelling process may introduc

  4. Concurrent Models for Object Execution

    OpenAIRE

    Diertens, B.

    2012-01-01

    In previous work we developed a framework of computational models for the concurrent execution of functions on different levels of abstraction. It shows that the traditional sequential execution of function is just a possible implementation of an abstract computational model that allows for the concurrent execution of functions. We use this framework as base for the development of abstract computational models that allow for the concurrent execution of objects.

  5. Economic explanations for concurrent sourcing

    DEFF Research Database (Denmark)

    Mols, Niels Peter

    2010-01-01

    Concurrent sourcing is a phenomenon where firms simultaneously make and buy the same good, i.e. they simultaneously use the governance modes of market and hierarchy. Though concurrent sourcing seems to be widespread, few studies of sourcing have focused on this phenomenon. This paper reviews diff...... different economic explanations for why firms use concurrent sourcing. The distinctive features of the explanations are compared, and it is discussed how they may serve as a springboard for research on concurrent sourcing. Managerial implications are also offered....

  6. Combustion Analysis of a CI Engine Performance Using Waste Cooking Biodiesel Fuel with an Artificial Neural Network Aid

    Directory of Open Access Journals (Sweden)

    Gholamhassan NAJAFI

    2007-01-01

    Full Text Available A comprehensive combustion analysis has been conducted to evaluate the performance of a commercial DI engine, water cooled two cylinders, in-line, naturally aspirated, RD270 Ruggerini diesel engine using waste vegetable cooking oil as an alternative fuel. In order to compare the brake power and the torques values of the engine, it has been tested under same operating conditions with diesel fuel and waste cooking biodiesel fuel blends. The results were found to be very comparable. The properties of biodiesel produced from waste vegetable oil was measured based on ASTM standards. The total sulfur content of the produced biodiesel fuel was 18 ppm which is 28 times lesser than the existing diesel fuel sulfur content used in the diesel vehicles operating in Tehran city (500 ppm. The maximum power and torque produced using diesel fuel was 18.2 kW and 64.2 Nm at 3200 and 2400 rpm respectively. By adding 20% of waste vegetable oil methyl ester, it was noticed that the maximum power and torque increased by 2.7 and 2.9% respectively, also the concentration of the CO and HC emissions have significantly decreased when biodiesel was used. An artificial neural network (ANN was developed based on the collected data of this work. Multi layer perceptron network (MLP was used for nonlinear mapping between the input and the output parameters. Different activation functions and several rules were used to assess the percentage error between the desired and the predicted values. The results showed that the training algorithm of Back Propagation was sufficient enough in predicting the engine torque, specific fuel consumption and exhaust gas components for different engine speeds and different fuel blends ratios. It was found that the R2 (R: the coefficient of determination values are 0.99994, 1, 1 and 0.99998 for the engine torque, specific fuel consumption, CO and HC emissions, respectively.

  7. 并行工程中下游阶段启动时间的实时确定%QUANTITATIVE APPROACH TO REAL TIME STARTUP TIME DETERMINATION OF DOWNSTREAM PHASES IN CONCURRENT ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    吕常魁; 姜澄宇; 王宁生

    2004-01-01

    Implementation of simultaneous execution phases in the concurrent engineering (CE) needs careful planning when the downstream phase could be activated as the upstream phase developed to a certain point. The determination of startup time of overlapping jobs in CE has long been a disturbance in manufacturing industry implementing CE programs. A novel model based on both fuzzy logic and neural network is proposed to mathematically formulate the inter-connective information between the two coupled phases in CE projects, and to determine the startup time of downstream phases in real time. The information transferring between the two coupled phases is quantified by using the negative Shannon entropy. Based on this algorithm, a PDM-based framework is proposed to narrow the gap between pro-duct design and manufacture, in which five modules are built to monitor, reshuffle and implement the simultaneous executing processes. Finally, an example is given to illustrate applications of the algorithm in the real world.%在并行工程的实施过程中,上下游阶段交叠形式的不合理安排将会给产品的开发带来不可预见的风险.如何决定各并行阶段的启动时间一直是困扰实施并行工程企业的问题.对于这方面的研究工作目前大多只限于概念模型分析的层面,而没有具体的数学模型.文中应用 Shannon信息熵量化了上下游阶段的交互信息和系统的有序度,建立了基于多层次模糊综合评判和BP神经网络的动态模型来实时确定下游阶段的启动时间.最后给出了基于PDM的实施框架和该模型的应用实例.

  8. CRDTs: Consistency without concurrency control

    CERN Document Server

    Letia, Mihai; Shapiro, Marc

    2009-01-01

    A CRDT is a data type whose operations commute when they are concurrent. Replicas of a CRDT eventually converge without any complex concurrency control. As an existence proof, we exhibit a non-trivial CRDT: a shared edit buffer called Treedoc. We outline the design, implementation and performance of Treedoc. We discuss how the CRDT concept can be generalised, and its limitations.

  9. A Lower Bound on Concurrence

    Institute of Scientific and Technical Information of China (English)

    LIU Li-Guo; TIAN Cheng-Lin; CHEN Ping-Xing; YUAN Nai-Chang

    2009-01-01

    We derive an analytical lower bound on the concurrence for bipartite quantum systems with an improved computable cross norm or realignment criterion and an improved positive partial transpose criterion respectively.Furthermore we demonstrate that our bound is better than that obtained from the local uncertainty relations criterion with optimal local orthogonal observables which is known as one of the best estimations of concurrence.

  10. The combination of glycerol metabolic engineering and drug resistance marker-aided genome shuffling to improve very-high-gravity fermentation performances of industrial Saccharomyces cerevisiae.

    Science.gov (United States)

    Wang, Pin-Mei; Zheng, Dao-Qiong; Liu, Tian-Zhe; Tao, Xiang-Lin; Feng, Ming-Guang; Min, Hang; Jiang, Xin-Hang; Wu, Xue-Chang

    2012-03-01

    A challenge associated with the ethanol productivity under very-high-gravity (VHG) conditions, optimizing multi-traits (i.e. byproduct formation and stress tolerance) of industrial yeast strains, is overcome by a combination of metabolic engineering and genome shuffling. First, industrial strain Y12 was deleted with a glycerol exporter Fps1p and hetero-expressed with glyceraldehydes-3-phosphate dehydrogenase, resulting in the modified strain YFG12 with lower glycerol yield. Second, YFG12 was subjected to three rounds of drug resistance marker-aided genome shuffling to increase its ethanol tolerance, and the best shuffled strain TS5 was obtained. Compared with wild strain Y12, shuffled strain TS5 not only decreased glycerol formation by 14.8%, but also increased fermentation rate and ethanol yield by 3.7% and 7.6%, respectively. Moreover, the system of genetic modification and Cre/loxP in aid of three different drug-resistance markers presented in the study significantly improved breeding efficiency and will facilitate the application of breeding technologies in prototrophic industrial microorganisms.

  11. Partnership concurrency and coital frequency.

    Science.gov (United States)

    Gaydosh, Lauren; Reniers, Georges; Helleringer, Stéphane

    2013-09-01

    National HIV prevalence estimates across sub-Saharan Africa range from less than 1 percent to over 25 percent. Recent research proposes several explanations for the observed variation, including prevalence of male circumcision, levels of condom use, presence of other sexually transmitted infections, and practice of multiple concurrent partnerships. However, the importance of partnership concurrency for HIV transmission may depend on how it affects coital frequency with each partner. The coital dilution hypothesis suggests that coital frequency within a partnership declines with the addition of concurrent partners. Using sexual behavior data from rural Malawi and urban Kenya, we investigate the relationship between partnership concurrency and coital frequency, and find partial support for the coital dilution hypothesis. We conclude the paper with a discussion of our findings in light of the current literature on concurrency.

  12. VLSI architecture for concurrent data structures

    International Nuclear Information System (INIS)

    Concurrent data structures simplify the development of concurrent programs by encapsulating commonly used mechanisms for synchronization and communication into data structures. This thesis develops a notation for describing concurrent data structures, presents examples of concurrent data structures, and describes an architecture to support concurrent data structures. Concurrent Smalltalk (CST), a derivative of Smalltalk-80 with extensions for concurrency, is developed to describe concurrent data structures. CST allows the programmer to specify objects that are distributed over the nodes of a concurrent computer. These distributed objects have many constituent objects and thus can process many messages simultaneously. They are the foundation upon which concurrent data structures are built. Considering graphs as concurrent data structures, graph algorithms are presented for the shortest-path problem, the max-flow problem, and graph partitioning. These algorithms introduce new synchronization techniques to achieve better performance than existing algorithms. A message passing, concurrent architecture is developed that exploits the characteristics of VLSI technology to support concurrent data structures

  13. Characterization of infectious aerosols in health care facilities: an aid to effective engineering controls and preventive strategies.

    Science.gov (United States)

    Cole, E C; Cook, C E

    1998-08-01

    Assessment of strategies for engineering controls for the prevention of airborne infectious disease transmission to patients and to health care and related workers requires consideration of the factors relevant to aerosol characterization. These factors include aerosol generation, particle size and concentrations, organism viability, infectivity and virulence, airflow and climate, and environmental sampling and analysis. The major focus on attention to engineering controls comes from recent increases in tuberculosis, particularly the multidrug-resistant varieties in the general hospital population, the severely immunocompromised, and those in at-risk and confined environments such as prisons, long-term care facilities, and shelters for the homeless. Many workers are in close contact with persons who have active, undiagnosed, or insufficiently treated tuberculosis. Additionally, patients and health care workers may be exposed to a variety of pathogenic human viruses, opportunistic fungi, and bacteria. This report therefore focuses on the nature of infectious aerosol transmission in an attempt to determine which factors can be systematically addressed to result in proven, applied engineering approaches to the control of infectious aerosols in hospital and health care facility environments. The infectious aerosols of consideration are those that are generated as particles of respirable size by both human and environmental sources and that have the capability of remaining viable and airborne for extended periods in the indoor environment. This definition precludes skin and mucous membrane exposures occurring from splashes (rather than true aerosols) of blood or body fluids containing infectious disease agents. There are no epidemiologic or laboratory studies documenting the transmission of bloodborne virus by way of aerosols. PMID:9721404

  14. New methods of concurrent checking

    CERN Document Server

    Goessel, Michael; Sogomonyan, Egor; Marienfeld, Daniel

    2008-01-01

    Written by a team of two leading experts and two very successful young former PhD students, New Methods of Concurrent Checking describes new methods of concurrent checking, such as partial duplication, use of output dependencies, complementary circuits, self-dual parity, self-dual duplication and others. A special chapter demonstrates how the new general methods of concurrent checking can be more specifically applied to regular structures to obtain optimum results. This is exemplified for all types of adders up to 64 bits with a level of detail never before presented in the literature. The cle

  15. A CAD MODEL FOR FUZZY CONCURRENT TOLERANCE

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Research situation of concurrent tolerance design has been analyzed. As fuzzy factors are objective and unavoidable in concurrent tolerance design, fuzzy optimization theory is applied in the design. A new mathematical model of concurrent tolerance design is constructed.

  16. Electrical engineering design using characterized elements; Conception en genie electrique a l'aide d'elements caracterises

    Energy Technology Data Exchange (ETDEWEB)

    Demni, H.E.

    2004-10-15

    This work treats systematic design of energy transformation structures used in Electrical Engineering. We propose an approach dedicated to design by association of characterized elements. Starting from a set of specifications, the designer has to define a coherent structure by assembling predefined elements. Within this framework, we adopt a characterization approach that takes into account various criteria necessary for design. Then, this approach allowed us to develop methodologies for designing electric energy transformation structures. These methodologies were used to implement a software application based on three tools: a data base as an elements library, a graphic tool allowing the construction of energy transformation structures, an expert module which helps the designer in his work. (author)

  17. How the biodiversity sciences may aid biological tools and ecological engineering to assess the impact of climatic changes.

    Science.gov (United States)

    Morand, S; Guégan, J-F

    2008-08-01

    This paper addresses how climate changes interact with other global changes caused by humans (habitat fragmentation, changes in land use, bioinvasions) to affect biodiversity. Changes in biodiversity at all levels (genetic, population and community) affect the functioning of ecosystems, in particular host-pathogen interactions, with major consequences in health ecology (emergence and re-emergence; the evolution of virulence and resistance). In this paper, the authors demonstrate that the biodiversity sciences, epidemiological theory and evolutionary ecology are indispensable in assessing the impact of climate changes, and also for modelling the evolution of host-pathogen interactions in a changing environment. The next step is to apply health ecology to the science of ecological engineering. PMID:18819665

  18. Artificial concurrent catalytic processes involving enzymes.

    Science.gov (United States)

    Köhler, Valentin; Turner, Nicholas J

    2015-01-11

    The concurrent operation of multiple catalysts can lead to enhanced reaction features including (i) simultaneous linear multi-step transformations in a single reaction flask (ii) the control of intermediate equilibria (iii) stereoconvergent transformations (iv) rapid processing of labile reaction products. Enzymes occupy a prominent position for the development of such processes, due to their high potential compatibility with other biocatalysts. Genes for different enzymes can be co-expressed to reconstruct natural or construct artificial pathways and applied in the form of engineered whole cell biocatalysts to carry out complex transformations or, alternatively, the enzymes can be combined in vitro after isolation. Moreover, enzyme variants provide a wider substrate scope for a given reaction and often display altered selectivities and specificities. Man-made transition metal catalysts and engineered or artificial metalloenzymes also widen the range of reactivities and catalysed reactions that are potentially employable. Cascades for simultaneous cofactor or co-substrate regeneration or co-product removal are now firmly established. Many applications of more ambitious concurrent cascade catalysis are only just beginning to appear in the literature. The current review presents some of the most recent examples, with an emphasis on the combination of transition metal with enzymatic catalysis and aims to encourage researchers to contribute to this emerging field.

  19. Biofabrication and in vitro study of hydroxyapatite/mPEG-PCL-mPEG scaffolds for bone tissue engineering using air pressure-aided deposition technology

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Cho-Pei, E-mail: cpjiang@nfu.edu.tw [Department of Power Mechanical Engineering, National Formosa University, Yunlin County, Taiwan (China); Chen, Yo-Yu, E-mail: f90125@hotmail.com [Institute of Mechanical and Electro-Mechanical Engineering, National Formosa University, Yunlin County, Taiwan (China); Hsieh, Min-Fa, E-mail: mfhsieh@cycu.edu.tw [Department of Biomedical Engineering, Chung Yuan Christian University, Chung Li, Taiwan (China)

    2013-03-01

    The aims of this study were to fabricate biopolymer and biocomposite scaffolds for bone tissue engineering by an air pressure-aided deposition system and to carry out osteoblast cell culture tests to validate the biocompatibility of fabricated scaffolds. A mPEG-PCL-mPEG triblock copolymer was synthesized as a biopolymer material. Biocomposite material was composed of synthesized biopolymer and hydroxyapatite (HA) with a mean diameter of 100 {mu}m. The weight ratio of HA added to the synthesized biopolymer was 0.1, 0.25, 0.5 and 1. The experimental results show that the maximum average compressive strength of biocomposite scaffolds, made of weight ratio 0.5, with mean pore size of 410 {mu}m (porosity 81%) is 18.38 MPa which is two times stronger than that of biopolymer scaffolds. Osteoblast cells, MC3T3-E1, were seeded on both types of fabricated scaffolds to validate the biocompatibility using methylthianzol tetrazolium (MTT) assay and cell morphology observation. After 28 days of in vitro culturing, the seeded osteoblasts were well distributed in the interior of both types of scaffolds. Furthermore, MTT experimental results show that the cell viability of the biocomposite scaffold is higher than that of the biopolymer scaffold. This indicates that adding HA into synthesized biopolymer can enhance compressive strength and the proliferation of the osteoblast cell. Highlights: Black-Right-Pointing-Pointer A mPEG-PCL-mPEG copolymer was synthesized as a biopolymer. Black-Right-Pointing-Pointer Biocomposite was made of adding hydroxyapatite (HA) in biopolymer. Black-Right-Pointing-Pointer Biopolyer and biocomposite scaffolds were made by an air pressure-aided deposition system. Black-Right-Pointing-Pointer Average compressive strength of biocomposite scaffold is 18.38 MPa. Black-Right-Pointing-Pointer After 28 days in vitro cell culturing, adding HA into biopolymer can enhance the proliferation.

  20. Object-oriented CAD data-base support for software reusability in computer-aided software engineering environments

    Energy Technology Data Exchange (ETDEWEB)

    Poulin, J.S.

    1989-01-01

    There is currently a large research effort underway to develop new techniques and methods for the efficient development of software. However, much of this effort ignores the vast sum of knowledge that has been acquired through the experiences in the field of engineering CAD, especially in the area of VLSI design. Much of what has been learned in this area centers on database support for the design process, and in particular, efficient object-oriented modeling techniques for software design data. It is believed that the data model for software is a central issue surrounding the development of CASE systems. Recognizing that great gains in software productivity will be realized only when software developed for one application is reused in subsequent applications, it is necessary to consider ways to support reuse through the data model used in these CASE environments. Awareness of these reusability issues has led to the development of a new object-oriented semantic data model for use in CASE environments. The proposed semantic data model for software is based on the molecular object model used in CAD, but has been enhanced to capture and support more of the software development cycle. The model differs from the molecular object model in that where the molecular model defines an object as being composed of only an interface and an implementation, this model distinguishes between the interface used for defining an object and an interface that is used to call an object. The comprehensive model structure incorporates a classification and retrieval mechanism designed to help map conceptual requirements to existing components in the software archive.

  1. Managing complexity of control software through concurrency

    NARCIS (Netherlands)

    Hilderink, Gerald Henk

    2005-01-01

    In this thesis, we are concerned with the development of concurrent software for embedded systems. The emphasis is on the development of control software. Embedded systems are concurrent systems whereby hardware and software communicate with the concurrent world. Concurrency is essential, which cann

  2. Some Properties of D-Concurrence

    Institute of Scientific and Technical Information of China (English)

    韦娜娜; 李愿

    2012-01-01

    In this note,we give a new lower bound for the concurrence,which is related to D-concurrence.For the Werner states,we compare that this D-concurrence bound with the other known bound.In addition,some of new upper and lower bounds of D-concurrence are given.

  3. STU attractors from vanishing concurrence

    CERN Document Server

    Lévay, Péter

    2010-01-01

    Concurrence is an entanglement measure characterizing the {\\it mixed} state bipartite correlations inside of a pure state of an $n$-qubit system. We show that after organizing the charges and the moduli in the STU model of $N=2$, $d=4$ supergravity to a three-qubit state, for static extremal spherically symmetric BPS black hole solutions the vanishing condition for all of the bipartite concurrences on the horizon is equivalent to the attractor equations. As a result of this the macroscopic black hole entropy given by the three-tangle can be reinterpreted as a linear entropy characterizing the {\\it pure} state entanglement for an arbitrary bipartite split. Both for the BPS and non-BPS cases explicit expressions for the concurrences are obtained, with their vanishing on the horizon is demonstrated.

  4. Foreign aid

    DEFF Research Database (Denmark)

    Tarp, Finn

    2008-01-01

    Foreign aid has evolved significantly since the Second World War in response to a dramatically changing global political and economic context. This article (a) reviews this process and associated trends in the volume and distribution of foreign aid; (b) reviews the goals, principles...... and institutions of the aid system; and (c) discusses whether aid has been effective. While much of the original optimism about the impact of foreign aid needed modification, there is solid evidence that aid has indeed helped further growth and poverty reduction...

  5. Aid Effectiveness

    DEFF Research Database (Denmark)

    Arndt, Channing; Jones, Edward Samuel; Tarp, Finn

    Controversy over the aggregate impact of foreign aid has focused on reduced form estimates of the aid-growth link. The causal chain, through which aid affects developmental outcomes including growth, has received much less attention. We address this gap by: (i) specifying a structural model...... of the main relationships; (ii) estimating the impact of aid on a range of final and intermediate outcomes; and (iii) quantifying a simplied representation of the full structural form, where aid impacts on growth through key intermediate outcomes. A coherent picture emerges: aid stimulates growth and reduces...

  6. A concurrent design approach and model management support to prevent inconsistencies in multidisciplinary modelling and simulation

    OpenAIRE

    Zhang, Xiaochen; Jan F. Broenink

    2013-01-01

    Cyber-physical systems are multidisciplinary systems which involve different engineering disciplines in their design. Each engineering discipline tends to use its own domain-specific languages and tools to model different aspects of a system concurrently. The concurrent modelling process may introduce inconsistencies due to lack of common knowledge and communication among domain experts. Especially for co-modelling and co-simulation developments, a huge amount of models, versions of models and...

  7. AIDS (image)

    Science.gov (United States)

    AIDS (acquired immune deficiency syndrome) is caused by HIV (human immunodeficiency virus), and is a syndrome that ... life-threatening illnesses. There is no cure for AIDS, but treatment with antiviral medication can suppress symptoms. ...

  8. Hearing Aids

    Science.gov (United States)

    ... more in both quiet and noisy situations. Hearing aids help people who have hearing loss from damage ... your doctor. There are different kinds of hearing aids. They differ by size, their placement on or ...

  9. Bisimulation for models in concurrency

    DEFF Research Database (Denmark)

    Nielsen, Mogens; Clausen, Christian

    1994-01-01

    Recently, Joyal, Nielsen and Winskel suggested a categorical definition of bisimulation, applicable to a wide range of models in concurrency with an accompanying notion af observations. The definition is in terms of span of open maps, and it coincides with Park and Milner's strong bisimulation...

  10. Concurrency & Asynchrony in Declarative Workflows

    DEFF Research Database (Denmark)

    Debois, Søren; Hildebrandt, Thomas; Slaats, Tijs

    2015-01-01

    Declarative or constraint-based business process and workflow notations have received increasing interest in the last decade as possible means of addressing the challenge of supporting at the same time flexibility in execution, adaptability and compliance. However, the definition of concurrent...

  11. Visualization of Concurrent Program Executions

    Science.gov (United States)

    Artho, Cyrille; Havelund, Klaus; Honiden, Shinichi

    2007-01-01

    Various program analysis techniques are efficient at discovering failures and properties. However, it is often difficult to evaluate results, such as program traces. This calls for abstraction and visualization tools. We propose an approach based on UML sequence diagrams, addressing shortcomings of such diagrams for concurrency. The resulting visualization is expressive and provides all the necessary information at a glance.

  12. The composition of concurrent programs

    Science.gov (United States)

    Chandy, K. Mani; Taylor, Stephen

    1989-01-01

    A notation is presented for concurrent programs called program composition notation (PCN). The notation is being implemented at Caltech on multicomputers (a network of computers that communicate by sending and receiving messages). A fragment of this notation has been implemented on a data-parallel computer, the Connection Machine. The central ideas underlying PCN are discussed.

  13. True Concurrency can be Traced

    DEFF Research Database (Denmark)

    Engberg, Uffe Henrik

    1990-01-01

    In this paper sets of labelled partial orders are employed as fundamental mathematical entities for modelling nondeterministic and concurrent processes thereby obtaining so-called noninterleaving semantics. Based on closures of sets of labelled partial orders, a simple algebraic language with ref...

  14. Concurrent Models for Object Execution

    NARCIS (Netherlands)

    B. Diertens

    2012-01-01

    In previous work we developed a framework of computational models for the concurrent execution of functions on different levels of abstraction. It shows that the traditional sequential execution of function is just a possible implementation of an abstract computational model that allows for the conc

  15. Relationships between models of concurrency

    DEFF Research Database (Denmark)

    Nielsen, Mogens; Sassone, Vladimiro; Winskel, Glynn

    1994-01-01

    Models for concurrency can be classified with respect to the three relevant parameters: behaviour/system, interleaving/noninterleaving, linear/branching time. When modelling a process, a choice concerning such parameters corresponds to choosing the level of abstraction of the resulting semantics...

  16. Interactive state-space analysis of concurrent systems

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, E.T.; Razouk, R.R.

    1987-10-01

    The introduction of concurrency into programs has added to the complexity of the software design process. This is most evident in the design of communications protocols where concurrency is inherent to the behavior of the system. The complexity exhibited by such software systems makes more evident the need for computer-aided tools for automatically analyzing behavior. The Distributed Systems project at UCI has been developing techniques and tools, based on Petri nets, which support the design and evaluation of concurrent software systems. Techniques based on constructing reachability graphs that represent projections and selections of complete state-spaces have been developed. This paper focuses attention on the computer-aided analysis of these graphs for the purpose of proving correctness of the modeled system. The application of the analysis technique to evaluating simulation results for correctness is discussed. The tool which supports this analysis (the reachability graph analyzer, RGA) is also described. This tool provides mechanisms for proving general system properties (e.g., deadlock-freeness) as well as system-specific properties. The tool is sufficiently general to allow a user to apply complex user-defined analysis algorithms to reachability graphs. The alternating-bit protocol, with a bounded channel, is used to demonstrate the power of the tool and to point to future extensions.

  17. Group Design Problems in Engineering Design Graphics.

    Science.gov (United States)

    Kelley, David

    2001-01-01

    Describes group design techniques used within the engineering design graphics sequence at Western Washington University. Engineering and design philosophies such as concurrent engineering place an emphasis on group collaboration for the solving of design problems. (Author/DDR)

  18. Data refinement for true concurrency

    Directory of Open Access Journals (Sweden)

    Brijesh Dongol

    2013-05-01

    Full Text Available The majority of modern systems exhibit sophisticated concurrent behaviour, where several system components modify and observe the system state with fine-grained atomicity. Many systems (e.g., multi-core processors, real-time controllers also exhibit truly concurrent behaviour, where multiple events can occur simultaneously. This paper presents data refinement defined in terms of an interval-based framework, which includes high-level operators that capture non-deterministic expression evaluation. By modifying the type of an interval, our theory may be specialised to cover data refinement of both discrete and continuous systems. We present an interval-based encoding of forward simulation, then prove that our forward simulation rule is sound with respect to our data refinement definition. A number of rules for decomposing forward simulation proofs over both sequential and parallel composition are developed.

  19. 36 CFR 292.69 - Concurrent reclamation.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Concurrent reclamation. 292... reclamation. Plans of operations involving locatable minerals, operating plans involving outstanding mineral... practicable, that reclamation proceed concurrently with the mineral operation....

  20. Concurrent Lymphoma and Pancreatic Adenocarcinoma

    OpenAIRE

    Jiun Miin Lai; Mehrdad Nikfarjam; Peter Crowley

    2011-01-01

    Context Retroperitoneal lymph node enlargement in patients with pancreatic cancer is sometimes treated as incurable disease. Nonmetastatic causes of lymphadenopathy should however be considered. Case reports Two cases of significant retroperitoneal lymphadenopathy in the setting of pancreatic cancer, treated by pancreaticoduodenectomy and lymph node dissection are described. Both cases had a final diagnosis of concurrent pancreatic cancer and lymphoma with no evidence of pancreatic lymph node...

  1. Concurrent Delay in Construction Disputes

    DEFF Research Database (Denmark)

    Cavaleri, Sylvie Cécile

    the delay is contractually defined as a contractor's risk, the contractor is liable to pay liquidated damages to the employer; if it is not, the contractor can under certain circumstances claim an extension of time and in some cases also economic compensation from the employer. The situation where a given...... solutions to the issue of concurrent delay in a comparative perspective between common and civil law systems, with an emphasis on Danish and English law....

  2. PyCSP - controlled concurrency

    DEFF Research Database (Denmark)

    Friborg, Rune Møllegaard; Vinter, Brian; Bjørndalen, John Markus

    2010-01-01

    Producing readable and correct programs while at the same time taking advantage of multi-core architectures is a challenge. PyCSP is an implementation of Communicating Sequential Processes algebra (CSP) for the Python programming language, that take advantage of CSP's formal and verifiable approach...... to controlling concurrency and the readability of Python source code. We describe PyCSP, demonstrate it through examples and demonstrate how PyCSP compares to Pthreads in a master-worker benchmark....

  3. PyCSP - controlled concurrency

    DEFF Research Database (Denmark)

    Friborg, Rune Møllegaard; Vinter, Brian; Bjørndalen, John Markus

    Producing readable and correct programs while at the same time taking advantage of multi-core architectures is a challenge. PyCSP is an implementation of Communicating Sequential Processes algebra (CSP) for the Python programming language, taking advantage of CSP’s formal and verifiable approach...... to controlling concurrency and the readability of Python source code. We describe PyCSP, demonstrate it through examples and demonstrate how PyCSP compares to Pthreads using a benchmark....

  4. Concurrent chemoradiation for vaginal cancer.

    Directory of Open Access Journals (Sweden)

    David T Miyamoto

    Full Text Available BACKGROUND: It is not known whether the addition of chemotherapy to radiation therapy improves outcomes in primary vaginal cancer. Here, we review clinical outcomes in patients with primary vaginal cancer treated with radiation therapy (RT or concurrent chemoradiation therapy (CRT. METHODS: Seventy-one patients with primary vaginal cancer treated with definitive RT with or without concurrent chemotherapy at a single institution were identified and their records reviewed. A total of 51 patients were treated with RT alone; 20 patients were treated with CRT. Recurrences were analyzed. Overall survival (OS and disease-free survival (DFS rates were estimated using the Kaplan-Meier method. Cox regression analysis was performed. RESULTS: The median age at diagnosis was 61 years (range, 18-92 years and the median follow-up time among survivors was 3.0 years. Kaplan-Meier estimates for OS and DFS differed significantly between the RT and CRT groups (3-yr OS = 56% vs. 79%, log-rank p = 0.037; 3-yr DFS = 43% vs. 73%, log-rank p = 0.011. Twenty-three patients (45% in the RT group had a relapse at any site compared to 3 (15% in the CRT group (p = 0.027. With regard to the sites of first relapse, 10 patients (14% had local only, 4 (6% had local and regional, 9 (13% had regional only, 1 (1% had regional and distant, and 2 (3% had distant only relapse. On univariate analysis, the use of concurrent chemotherapy, FIGO stage, tumor size, and date of diagnosis were significant predictors of DFS. On multivariate analysis, the use of concurrent chemotherapy remained a significant predictor of DFS (hazard ratio 0.31 (95% CI, 0.10-0.97; p = 0.04. CONCLUSIONS: Vaginal cancer results in poor outcomes. Adequate radiation dose is essential to ensure curative management. Concurrent chemotherapy should be considered for vaginal cancer patients.

  5. CREATIVITY ENGINEERING FOR CONTINUOUS AND DISCONTINUOUS INNOVATION

    OpenAIRE

    JUSTIN J. Y. LIN

    2007-01-01

    Concurrent engineering (CE) has been widely implemented in many industries so that developers can consider all elements of the product lifecycle during the product design phase. However, although concurrent engineering is a very effective approach for product design team-up, it does not help to generate new product concepts. To build a successful innovation model, research has investigated how concurrent engineering can be extended to a new concept which covers not only the downstream phase f...

  6. Creatine and Caffeine: Considerations for Concurrent Supplementation.

    Science.gov (United States)

    Trexler, Eric T; Smith-Ryan, Abbie E

    2015-12-01

    Nutritional supplementation is a common practice among athletes, with creatine and caffeine among the most commonly used ergogenic aids. Hundreds of studies have investigated the ergogenic potential of creatine supplementation, with consistent improvements in strength and power reported for exercise bouts of short duration (≤ 30 s) and high intensity. Caffeine has been shown to improve endurance exercise performance, but results are mixed in the context of strength and sprint performance. Further, there is conflicting evidence from studies comparing the ergogenic effects of coffee and caffeine anhydrous supplementation. Previous research has identified independent mechanisms by which creatine and caffeine may improve strength and sprint performance, leading to the formulation of multi-ingredient supplements containing both ingredients. Although scarce, research has suggested that caffeine ingestion may blunt the ergogenic effect of creatine. While a pharmacokinetic interaction is unlikely, authors have suggested that this effect may be explained by opposing effects on muscle relaxation time or gastrointestinal side effects from simultaneous consumption. The current review aims to evaluate the ergogenic potential of creatine and caffeine in the context of high-intensity exercise. Research directly comparing coffee and caffeine anhydrous is discussed, along with previous studies evaluating the concurrent supplementation of creatine and caffeine. PMID:26219105

  7. Creatine and Caffeine: Considerations for Concurrent Supplementation.

    Science.gov (United States)

    Trexler, Eric T; Smith-Ryan, Abbie E

    2015-12-01

    Nutritional supplementation is a common practice among athletes, with creatine and caffeine among the most commonly used ergogenic aids. Hundreds of studies have investigated the ergogenic potential of creatine supplementation, with consistent improvements in strength and power reported for exercise bouts of short duration (≤ 30 s) and high intensity. Caffeine has been shown to improve endurance exercise performance, but results are mixed in the context of strength and sprint performance. Further, there is conflicting evidence from studies comparing the ergogenic effects of coffee and caffeine anhydrous supplementation. Previous research has identified independent mechanisms by which creatine and caffeine may improve strength and sprint performance, leading to the formulation of multi-ingredient supplements containing both ingredients. Although scarce, research has suggested that caffeine ingestion may blunt the ergogenic effect of creatine. While a pharmacokinetic interaction is unlikely, authors have suggested that this effect may be explained by opposing effects on muscle relaxation time or gastrointestinal side effects from simultaneous consumption. The current review aims to evaluate the ergogenic potential of creatine and caffeine in the context of high-intensity exercise. Research directly comparing coffee and caffeine anhydrous is discussed, along with previous studies evaluating the concurrent supplementation of creatine and caffeine.

  8. COMPUTER AIDED ENGINEERING IN CONSTRUCTION EQUIPMENT RESEARCH INSTITUTE (PIMB)%计算机辅助工程在建筑设备研究所的应用

    Institute of Scientific and Technical Information of China (English)

    Andrzej; T.Machniewski; Mr; Janusz; Mysliwiec

    2001-01-01

    Questions of computer aided engineering work in Construction Equipment Research Institute is discussed in the article. Machinery and its units have been designed with computers in the Institute since the middle of the 70s. Afterwards some new software were bought and our software was developed as well. They were applied to solve more advanced calculations for complex construction machinery and hydraulic mobile cranes. Since the turn of the 70s and 80s computer methods have been applied in measurements and analyses of stresses, vibroacoustics and stability of machinery. The Institute has undertaken the integration of designing centres and the creation computer data base in the field of safety, ecology and ergonomy. Development of computer methods is also possible thanks to scientific co- operation with many countries which is fulfilled in a form of symposiums and conferences.%本文讨论了建筑设备研究所在计算机辅助工程研究中的一些问题.70年代中期该研究所就开始用计算机设计机器及其部件.后来研究所购买了一些相关软件同时也开发了自己的设计软件并在液压起重机和其它建筑机械的设计计算中得到了应用.70~80年代计算机主要用于压力的分析与测量,机械的振动与稳定性分析.研究所从事机械设计、计算机数据库安全性研究及生态学、工效学方面的研究.在此也感谢其他国家的学者在计算机应用方面的交流与合作.

  9. Hearing Aids

    Science.gov (United States)

    ... prefer the open-fit hearing aid because their perception of their voice does not sound “plugged up.” ... My voice sounds too loud. The “plugged-up” sensation that causes a hearing aid user’s voice to ...

  10. Brand Aid

    DEFF Research Database (Denmark)

    Richey, Lisa Ann; Ponte, Stefano

    A critical account of the rise of celebrity-driven “compassionate consumption” Cofounded by the rock star Bono in 2006, Product RED exemplifies a new trend in celebrity-driven international aid and development, one explicitly linked to commerce, not philanthropy. Brand Aid offers a deeply informed...

  11. A Model for Concurrent Objects

    DEFF Research Database (Denmark)

    Sørensen, Morten U.

    1996-01-01

    We present a model for concurrent objects where obejcts interact by taking part in common events that are closely matched to form call-response pairs, resulting in resulting in rendez-vous like communications. Objects are built from primitive objects by parallel composition, encapsulation and hid...... and hiding. The behavour of a composite object is straightforwardly derived from the behavour of the constituent objects. Defining refinement as a strengthened form of trace inclusion, object composition and refinement togehter form a basis for step-wise development....

  12. Investigating the Alignment of Concurrent Design Strategies with Business Strategies

    Directory of Open Access Journals (Sweden)

    Heidar Mirfakhredini

    2013-08-01

    Full Text Available In recent years, managing the interface between design and other activities has received considerable attention. Effective coordination among these areas is therefore vital for effectiveness of the organization. The ideal situation would be continuous interdepartmental contact with well-developed channels of communication. In this study, the best strategy for product design department has been chosen using the strategic formulation framework with fuzzy approach. Subsequently, alignment of each functional design strategy with SAPCO business strategies has been explained. Findings indicate that developing partnerships with global automotive and engineering design companies and building strategic alliances with rival firms to achieve competitive advantages have maximum alignment with business strategies. In addition, findings provide a basis for firms in evaluating the concurrent design strategies and a reference for them to strengthen their concurrent capabilities. There are few reports on sustained use of concurrent design as an on-going strategic process in an organization. This study aims at contributing to the concurrent design solutions.

  13. Concurrent analysis: a pragmatic justification.

    Science.gov (United States)

    Snowden, Austyn; Atkinson, John

    2012-04-01

    Concurrent analysis (CA) is a process of synthesizing conceptually equivalent data for the purpose of producing a coherent and predictive model in social science. The process of CA is detailed. In short, CA uses Thagard's concept of coherence as a method of explicating links between mental representations. The product is a wide analysis of all pertinent data. This paper provides a philosophical justification for the need and function of CA. The paper is divided into three sections. The first section reviews some problems with the metasynthetic literature. The purpose of this is that CA can be initially understood as a branch of this type of synthesis. The second section links Risjord's post-paradigmatic position to Rorty's version of pragmatism in order to show the importance of the concept of coherence to these views. The reason for linking these issues is that CA is grounded in rejection of ontological priority. Instead it prioritises a pragmatic conception of coherence. The final section details the mechanics of CA. Concurrent analysis is presented as the most coherent method of synthesizing certain types of narrative evidence if pragmatism is prioritized over ontology. Examples are given from published studies using CA to illustrate the detail of the analysis and the practical value of the product. The examples show that CA appears useful under certain circumstances. These circumstances will be specified, and strengths and weaknesses of the method will be discussed. PMID:22405019

  14. Hearing Aid

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A man realized that he needed to purchase ahearing aid, but he was unwilling to spend muchmoney. "How much do they run?"he asked theclerk. "That depends," said. the salesman. "Theyrun from 2 to 2000."

  15. Hearing Aid

    Science.gov (United States)

    ... and Food and Drug Administration Staff FDA permits marketing of new laser-based hearing aid with potential ... feeds Follow FDA on Twitter Follow FDA on Facebook View FDA videos on YouTube View FDA photos ...

  16. Steps in Modular Specifications for Concurrent Modules

    DEFF Research Database (Denmark)

    Da Rocha Pinto, Pedro; Dinsdale-Young, Thomas; Gardner, Philippa

    2015-01-01

    The specification of a concurrent program module is a difficult problem. The specifications must be strong enough to enable reasoning about the intended clients without reference to the underlying module implementation. We survey a range of verification techniques for specifying concurrent modules......, in particular highlighting four key concepts: auxiliary state, interference abstraction, resource ownership and atomicity. We show how these concepts combine to provide powerful approaches to specifying concurrent modules....

  17. The Balanced Cube: A Concurrent Data Structure

    OpenAIRE

    Dally, William J.; Seitz, Charles L.

    1985-01-01

    This paper describee the balanced cube, a new data structure for implementing ordered seta. Conventional dats structures such as heaps, balanced trees and B-trees have root bottlenecks which limit their potential concurrency and make them unable to take advantage of the computing potential of concurrent machines. The balanced cube achieves greater concurrency by eliminating the root bottleneck; an operation in the balanced cube can be initiated from any node. The throughput of ...

  18. Teaching Concurrency: Theory in Practice

    DEFF Research Database (Denmark)

    Aceto, Luca; Ingolfsdottir, Anna; Larsen, Kim Guldstrand;

    2009-01-01

    Teaching courses that rely on sound mathematical principles is nowadays a challenging task at many universities. On the one hand there is an increased demand for educating students in these areas, on the other hand there are more and more students being accepted with less adequate skills in mathe......Teaching courses that rely on sound mathematical principles is nowadays a challenging task at many universities. On the one hand there is an increased demand for educating students in these areas, on the other hand there are more and more students being accepted with less adequate skills...... in mathematics. We report here on our experiences in teaching concurrency theory over the last twenty years or so to students ranging from mathsphobic bachelor students to sophisticated doctoral students. The contents of the courses, the material on which they are based and the pedagogical philosophy underlying...

  19. Concurrent Process Planning for Machined Parts

    Institute of Scientific and Technical Information of China (English)

    吴丹; 王先逵; 李志忠

    2002-01-01

    Detailed manufacturing information about the parts can help designers produce better designs. Detailed manufacturing information is conveyed to the designer through micro-circles within the concurrent design process for machined parts, focusing on instantaneous product design and process planning. The process has three key elements: a hierarchical architecture design of the concurrent process planning system, modeling and reengineering of the concurrent process planning, and modeling of information. The approach is successfully implemented and applied for concurrent design and process planning of some complicated parts.

  20. How does concurrent sourcing affect performance?

    DEFF Research Database (Denmark)

    Mols, Niels Peter

    2010-01-01

    /methodology/approach – Based on transaction cost, agency, neoclassical economic, knowledge-based, and resource-based theory, it is proposed to show how concurrent sourcing affects performance. Findings – The paper argues that concurrent sourcing improves performance when firms face a combination of volume uncertainty......Abstract Purpose – “Concurrent sourcing” is a term used by Parmigiani to describe the phenomenon where a firm simultaneously buys and makes the same good or service. The purpose of this paper is to develop propositions that suggest how concurrent sourcing affects performance. Design...

  1. Cfd Aided Development of a Si-Di Engine Aide au développement d'un moteur à injection directe d'essence par modélisation 3D

    Directory of Open Access Journals (Sweden)

    Henriot S.

    2006-12-01

    Full Text Available Gasoline Direct Injection (GDI appears to be the most relevant way to improve fuel efficiency of SI engines. But today, GDI is essentially regarded as a suitable technology for relatively high displacement engines, and the literature shows that the R&D effort on GDI engines is generally made for bores larger than 80 mm. For small bore engines (bore below 75 mm, locating an injector in already congested cylinder heads, with ultra lean stratified combustion capability while maintaining high engine specific power and proper cylinder head cooling is a real challenge. For such an engine, IFP is developing a 3-valve per cylinder engine (NSDI-3, based on a narrow spacingconcept, with a spark-plug-close-to-the-injector design and a suitable piston to confine the gasoline spray within the vicinity of the ignition location. This paper describes the contribution of 3D modeling to the development of this engine, from the initial work during the design of the prototype combustion chamber, to the development and tuning of the prototype engine on the test bench. Depuis quelques années, l'injection directe d'essence apparaÎt comme l'une des voies d'investigation les plus performantes pour améliorer le rendement des moteurs à allumage commandé. Cependant, cette technologie est, actuellement, plutôt réservée aux moteurs de cylindrée assez importante, et les travaux de R&D présentés dans la littérature font surtout état de développement pour des moteurs d'alésage supérieur à 80 mm. En ce qui concerne les petits moteurs (alésage inférieur à 75 mm, implanter un injecteur dans une culasse déjà largement encombrée, avec un fort potentiel de combustion en mélange très pauvre stratifié, tout en maintenant de bonnes performances moteur et un circuit de refroidissement bien dimensionné, constitue un véritable défi. Pour un tel moteur, l'Institut français du pétrole (IFP développe une solution à 3 soupapes par cylindre (NSDI-3, basée sur

  2. CONCURRENT PRODUCT PORTFOLIO PLANNING AND MIXED PRODUCT ASSEMBLY LINE BALANCING

    Institute of Scientific and Technical Information of China (English)

    BRYAN April; HU S Jack; KOREN Yoram

    2007-01-01

    Reconfigurable products and manufacturing systems have enabled manufacturers to provide "cost effective" variety to the market. In spite of these new technologies, the expense of manufacturing makes it infeasible to supply all the possible variants to the market for some industries. Therefore, the determination of the right number of product variants to offer in the product portfolios becomes an important consideration. The product portfolio planning problem had been independently well studied from marketing and engineering perspectives. However, advantages can be gained from using a concurrent marketing and engineering approach. Concurrent product development strategies specifically for reconfigurable products and manufacturing systems can allow manufacturers to select best product portfolios from marketing, product design and manufacturing perspectives. A methodology for the concurrent design of a product portfolio and assembly system is presented. The objective of the concurrent product portfolio planning and assembly system design problem is to obtain the product variants that will make up the product portfolio such that oversupply of optional modules is minimized and the assembly line efficiency is maximized. Explicit design of the assembly system is obtained during the solution of the problem. It is assumed that the demand for optional modules and the assembly times for these modules are known a priori. A genetic algorithm is used in the solution of the problem. The basic premise of this methodology is that the selected product portfolio has a significant impact on the solution of the assembly line balancing problem. An example is used to validate this hypothesis. The example is then further developed to demonstrate how the methodology can be used to obtain the optimal product portfolio. This approach is intended for use by manufacturers during the early design stages of product family design.

  3. Concurrency revisited: increasing and compelling epidemiological evidence

    Directory of Open Access Journals (Sweden)

    Mah Timothy L

    2011-06-01

    Full Text Available Abstract Multiple sexual partnerships must necessarily lie at the root of a sexually transmitted epidemic. However, that overlapping or concurrent partnerships have played a pivotal role in the generalized epidemics of sub-Saharan Africa has been challenged. Much of the original proposition that concurrent partnerships play such a role focused on modelling, self-reported sexual behaviour data and ethnographic data. While each of these has definite merit, each also has had methodological limitations. Actually, more recent cross-national sexual behaviour data and improved modelling have strengthened these lines of evidence. However, heretofore the epidemiologic evidence has not been systematically brought to bear. Though assessing the epidemiologic evidence regarding concurrency has its challenges, a careful examination, especially of those studies that have assessed HIV incidence, clearly indicates a key role for concurrency. Such evidence includes: 1 the early and dramatic rise of HIV infection in generalized epidemics that can only arise from transmission through rapid sequential acute infections and thereby concurrency; 2 clear evidence from incidence studies that a major portion of transmission in the population occurs via concurrency both for concordant negative and discordant couples; 3 elevation in risk associated with partner's multiple partnering; 4 declines in HIV associated with declines in concurrency; 5 bursts and clustering of incident infections that indicate concurrency and acute infection play a key role in the propagation of epidemics; and 6 a lack of other plausible explanations, including serial monogamy and non-sexual transmission. While other factors, such as sexually transmitted infections, other infectious diseases, biological factors and HIV sub-type, likely play a role in enhancing transmission, it appears most plausible that these would amplify the role of concurrency rather than alter it. Additionally, critics of

  4. Types of Hearing Aids

    Science.gov (United States)

    ... Devices Consumer Products Hearing Aids Types of Hearing Aids Share Tweet Linkedin Pin it More sharing options ... some features for hearing aids? What are hearing aids? Hearing aids are sound-amplifying devices designed to ...

  5. Computer-aided lens assembly.

    Science.gov (United States)

    Tomlinson, Richard; Alcock, Rob; Petzing, Jon; Coupland, Jeremy

    2004-01-20

    We propose a computer-aided method of lens manufacture that allows assembly, adjustment, and test phases to be run concurrently until an acceptable level of optical performance is reached. Misalignment of elements within a compound lens is determined by a comparison of the results of physical ray tracing by use of an array of Gaussian laser beams with numerically obtained geometric ray traces. An estimate of misalignment errors is made, and individual elements are adjusted in an iterative manner until performance criteria are achieved. The method is illustrated for the alignment of an air-spaced doublet. PMID:14765916

  6. Negotiating Aid

    DEFF Research Database (Denmark)

    Whitfield, Lindsay; Fraser, Alastair

    2011-01-01

    This article presents a new analytical approach to the study of aid negotiations. Building on existing approaches but trying to overcome their limitations, it argues that factors outside of individual negotiations (or the `game' in game-theoretic approaches) significantly affect the preferences...... which investigated the strategies these states have adopted in talks with aid donors, the sources of leverage they have been able to bring to bear in negotiations, and the differing degrees of control that they have been able to exercise over the policies agreed in negotiations and those implemented...

  7. Petri nets and other models of concurrency

    DEFF Research Database (Denmark)

    Nielsen, Mogens; Sassone, Vladimiro

    1998-01-01

    This paper retraces, collects, and summarises contributions of the authors - in collaboration with others - on the theme of Petri nets and their categorical relationships to other models of concurrency.......This paper retraces, collects, and summarises contributions of the authors - in collaboration with others - on the theme of Petri nets and their categorical relationships to other models of concurrency....

  8. New concurrent iterative methods with monotonic convergence

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Qingchuan [Michigan State Univ., East Lansing, MI (United States)

    1996-12-31

    This paper proposes the new concurrent iterative methods without using any derivatives for finding all zeros of polynomials simultaneously. The new methods are of monotonic convergence for both simple and multiple real-zeros of polynomials and are quadratically convergent. The corresponding accelerated concurrent iterative methods are obtained too. The new methods are good candidates for the application in solving symmetric eigenproblems.

  9. A Temporal Concurrent Constraint Programming Calculus

    DEFF Research Database (Denmark)

    Palamidessi, Catuscia; Valencia Posso, Frank Darwin

    2001-01-01

    The tcc model is a formalism for reactive concurrent constraint programming. In this paper we propose a model of temporal concurrent constraint programming which adds to tcc the capability of modeling asynchronous and non-deterministic timed behavior. We call this tcc extension the ntcc calculus...

  10. Interval-based Specification of Concurrent Objects

    DEFF Research Database (Denmark)

    Løvengreen, Hans Henrik; Sørensen, Morten U.

    1998-01-01

    We propose a logic for specifying the behaviour of concurrent objects, ie. concurrent entities that invoke operation of each other. The logic is an interval logic whith operation invocatins as primitive formulas. The strengths and deficiencies of the logic are illustrated by specifying a variety of...

  11. Declarative interpretations of session-based concurrency

    DEFF Research Database (Denmark)

    Cano, Mauricio; Rueda, Camilo; López-Acosta, Hugo-Andrés;

    2015-01-01

    paper, we investigate the relationship between operational and declarative models of session-based concurrency. We propose two interpretations of session π-calculus processes as declarative processes in linear concurrent constraint programming (lcc). They offer a basis on which both operational and...

  12. An Approach to Concurrent TTCN Test Generation

    Institute of Scientific and Technical Information of China (English)

    BI Jun; WU Jianping

    1999-01-01

    The basis of distributed system conformance testing is to test theconformance of each entity with its standard. This paper addresses theapproach to entity conformance testing based on concurrent TTCN. First apreliminary framework for entity conformance testing is introduced and aspecification model CEBE is presented. Then a test generation method,which could directly derive concurrent TTCN test suite from CEBE, isproposed.

  13. Has donor prioritization of HIV/AIDS displaced aid for other health issues?

    Science.gov (United States)

    Shiffman, Jeremy

    2008-03-01

    Advocates for many developing-world health and population issues have expressed concern that the high level of donor attention to HIV/AIDS is displacing funding for their own concerns. Even organizations dedicated to HIV/AIDS prevention and treatment have raised this issue. However, the issue of donor displacement has not been evaluated empirically. This paper attempts to do so by considering donor funding for four historically prominent health agendas--HIV/AIDS, population, health sector development and infectious disease control--over the years 1992 to 2005. The paper employs funding data from the Organization for Economic Cooperation and Development's (OECD) Development Assistance Committee, supplemented by data from other sources. Several trends indicate possible displacement effects, including HIV/AIDS' rapidly growing share of total health aid, a concurrent global stagnation in population aid, the priority HIV/AIDS control receives in US funding, and HIV/AIDS aid levels in several sub-Saharan African states that approximate or exceed the entirety of their national health budgets. On the other hand, aggregate donor funding for health and population quadrupled between 1992 and 2005, allowing for funding growth for some health issues even as HIV/AIDS acquired an increasingly prominent place in donor health agendas. Overall, the evidence indicates that displacement is likely occurring, but that aggregate increases in global health aid may have mitigated some of the crowding-out effects.

  14. Brand Aid

    DEFF Research Database (Denmark)

    Richey, Lisa Ann; Ponte, Stefano

    2011-01-01

    activists, scholars and venture capitalists, discusses the pros and cons of changing the world by ‘voting with your dollars’. Lisa Ann Richey and Stefano Ponte (Professor at Roskilde University and Senior Researcher at DIIS respectively), authors of Brand Aid: Shopping Well to Save the World, highlight how...

  15. Organização do trabalho no processo de desenvolvimento de produtos: a aplicação da engenharia simultânea em duas montadoras de veículos Work organization in the product development process: application of concurrent engineering by two automakers

    Directory of Open Access Journals (Sweden)

    Eduardo de Senzi Zancul

    2006-04-01

    Full Text Available Para reduzir o tempo necessário para lançar novos produtos no mercado, as empresas adotam uma nova abordagem de desenvolvimento de produtos baseada, principalmente, na engenharia simultânea e em times multifuncionais. Teoricamente, essa nova abordagem resulta em alterações importantes na organização do trabalho, que passa a ser executado em times envolvendo pessoas de várias áreas funcionais, atuando em conjunto do início ao fim dos projetos. No entanto, poucos estudos analisam a abrangência das mudanças que ocorrem na prática nas empresas. Nesse contexto, o objetivo deste artigo é analisar a forma como o trabalho de desenvolvimento de produtos é organizado nas empresas e discutir as diferenças entre a prática e os pressupostos teóricos. Para isso são realizados dois estudos de caso em montadoras de veículos comerciais. A pesquisa demonstra que a adoção de times e de um processo com atividades em paralelo não garantem a integração efetiva entre as áreas funcionais. Além disso, a pesquisa indica que parte relevante das atividades de projeto de novos produtos ainda é realizada individualmente, apesar das vantagens potenciais de se optar por uma organização mais flexível, autônoma e baseada em trabalho em grupos.To overcome the limitations of the traditional product development process and reduce product development lead times, companies are adopting a new product development approach based on concurrent engineering and multifunctional teams. In theory, this new approach significantly changes the way product development work is organized, and involves teams from various functional areas who work in concert from the inception to the conclusion of the project. However, few studies have analyzed the scope of the changes this new product development approach has wrought in company practices. In this context, this paper describes how product development work is organized in companies and discusses the differences between

  16. Concurrent Manipulation of Expanded AVL Trees

    Institute of Scientific and Technical Information of China (English)

    章寅; 许卓群

    1998-01-01

    The concurrent manipulation of an expanded AVL tree(EAVL tree)s considered in this paper.The presented system can support any number of concurrent processes which perform searching,insertion and deletion on the tree.Simulation results indicate the high performance of the system.Elaborate techniques are used to achieve such a system unavailable based on any known algorithms.Methods developed in this paper may provide new insights into other problems in the area of concurrent search structure manipulation.

  17. Formal Derivation of Concurrent Garbage Collectors

    CERN Document Server

    Pavlovic, Dusko; Smith, Douglas R

    2010-01-01

    Concurrent garbage collectors are notoriously difficult to implement correctly. Previous approaches to the issue of producing correct collectors have mainly been based on posit-and-prove verification or on the application of domain-specific templates and transformations. We show how to derive the upper reaches of a family of concurrent garbage collectors by refinement from a formal specification, emphasizing the application of domain-independent design theories and transformations. A key contribution is an extension to the classical lattice-theoretic fixpoint theorems to account for the dynamics of concurrent mutation and collection.

  18. Tactile Aids

    Directory of Open Access Journals (Sweden)

    Mohtaramossadat Homayuni

    1996-04-01

    Full Text Available Tactile aids, which translate sound waves into vibrations that can be felt by the skin, have been used for decades by people with severe/profound hearing loss to enhance speech/language development and improve speechreading.The development of tactile aids dates from the efforts of Goults and his co-workers in the 1920s; Although The power supply was too voluminous and it was difficult to carry specially by children, it was too huge and heavy to be carried outside the laboratories and its application was restricted to the experimental usage. Nowadays great advances have been performed in producing this instrument and its numerous models is available in markets around the world.

  19. Advances in computer-aided engineering: CAD/CAM-research at Delft University of Technology. Report of the VF-project CAD/CAM 1989-1994

    NARCIS (Netherlands)

    1994-01-01

    This book contains a collection of articles describing on-going CAD/CAM-research at several engineering faculties at Delft University of Technology. Two main themes covered in this book are 'Conceptual design of complex products' and 'Product modelling and product data exchange'.

  20. Low cost training aids and devices

    Science.gov (United States)

    Lawver, J.; Lee, A.

    1984-01-01

    The need for advanced flight simulators for two engine aircraft is discussed. Cost effectiveness is a major requirement. Other training aids available for increased effectiveness are recommended. Training aids include: (1) audio-visual slides; (2) information transfer; (3) programmed instruction; and (4) interactive training systems.

  1. 33 CFR 385.7 - Concurrency statements.

    Science.gov (United States)

    2010-07-01

    ... DEFENSE PROGRAMMATIC REGULATIONS FOR THE COMPREHENSIVE EVERGLADES RESTORATION PLAN General Provisions § 385.7 Concurrency statements. The administrative record of the programmatic regulations in this part..., Jacksonville District, 701 San Marco Blvd., Jacksonville, Florida 32207, or by accessing the...

  2. Neurological Complications of AIDS

    Science.gov (United States)

    ... Diversity Find People About NINDS Neurological Complications of AIDS Fact Sheet Feature Federal domestic HIV/AIDS information ... Where can I get more information? What is AIDS? AIDS (acquired immune deficiency syndrome) is a condition ...

  3. Mining sequential patterns to explain concurrent counterexamples

    OpenAIRE

    Leue, Stefan; Tabaei Befrouei, Mitra

    2013-01-01

    Concurrent systems are often modeled using an interleaving semantics. Since system designers tend to think sequentially, it is highly probable that they do not foresee some interleavings that their model encompasses. As a consequence, one of the main sources of failure in concurrent systems is unforeseen interleavings. In this paper, we devise an automated method for revealing unforeseen interleavings in the form of sequences of actions derived from counterexamples obtained by explicit state ...

  4. Flow Java: Declarative Concurrency for Java

    OpenAIRE

    Drejhammar, Frej

    2005-01-01

    This thesis presents the design, implementation, and evaluation of Flow Java, a programming language for the implementation of concurrent programs. Flow Java adds powerful programming abstractions for automatic synchronization of concurrent programs to Java. The abstractions added are single assignment variables (logic variables) and futures (read-only views of logic variables). The added abstractions conservatively extend Java with respect to types, parameter passing, a...

  5. SACO: Static analyzer for concurrent objects

    OpenAIRE

    Albert Albiol, Elvira; Arenas Sánchez, Purificación; Flores Montoya, A.; Genaim, Samir; Gómez-Zamalloa Gil, Miguel; Martín Martín, Enrique; Puebla, G.; Román Díez, Guillermo

    2014-01-01

    We present the main concepts, usage and implementation of SACO, a static analyzer for concurrent objects. Interestingly, SACO is able to infer both liveness(namely termination and resource boundedness) and safety properties (namely deadlock freedom) of programs based on concurrent objects. The system integrates auxiliary analyses such as points-to and may-happen-in-parallel, which are essential for increasing the accuracy of the aforementioned more complex properties. SACO provides accurate ...

  6. Templet: a Markup Language for Concurrent Programming

    OpenAIRE

    Vostokin, Sergey

    2014-01-01

    In this paper we propose a new approach to the description of a network of interacting processes in a traditional programming language. Special programming languages or extensions to sequential languages are usually designed to express the semantics of concurrent execution. Using libraries in C++, Java, C#, and other languages is more practical way of concurrent programming. However, this method leads to an increase in workload of a manual coding. Besides, stock compilers can not detect seman...

  7. Parallelism Via Concurrency at Multiple Levels

    OpenAIRE

    Latif, Kamran

    2014-01-01

    In this paper we examine the key elements determining the best performance of computing by increasing the frequency of a single chip and to get the minimum latency during execution of the programs to achieve best possible output. It is not enough to provide concurrent improvements in the hardware as Software also have to introduce concurrency in order to exploit the parallelism. The software parallelism is defined by the control and data dependency of programs whereas Hardware refers to the t...

  8. CAME-Toolsuite meet2trade - auf dem Weg zum Computer Aided Market Engineering. Abschlussbericht des Projekts Electronic Financial Brokerage als wissensintensive Dienstleistung - ein generischer Ansatz (EFB)

    OpenAIRE

    Weinhardt, Christof; Dinther, Clemens van; Grunenberg, Michael; Kolitz, Klaus; Kunzelmann, Matthias; Mäkiö, Juho; Weber, Ilka; Weltzien, Henning

    2006-01-01

    Die zunehmende Verbreitung von elektronischen Märkten aber auch die Fehlentwicklungen der letzten Jahre zeigen, dass eine strukturierte Vorgehensweise bei der Gestaltung und Implementierung elektronischer Märkte nicht nur sinnvoll, sondern auch notwendig ist. Ein wichtiger Schritt in diese Richtung wurde mit der im Rahmen des Projekts Electronic Financial Brokerage (EFB) entwickelten CAME-Toolsuite meet2trade gegangen.meet2trade unterstützt den gesamten Prozess des Market Engineering von der ...

  9. An Optimized Constraint Decomposition Method in Concurrent Engineering

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In order to facilitate solution, a complex problem is normally decomposed into many small sub-problems during product development process. Teams are formed to resolve each sub-problem. The original problem is resolved from solutions of sub-problems. Ideally, sub-problems are not only mutually independent but also inherent parameters of original problem. Solution of original problem can be directly derived from the collection of solutions from simplified sub-problems. In practice, the degree of interdependency is indeed reduced, sub-problems are neither totally independent nor all inherent parameters of original problem. This paper discusses team coordination under this condition and design solution from each team, which not only satisfies total requirements but also is an optimal one. The suggested optimized constraint decomposition method will insure workable Pareto solution.

  10. Current issues of the concurrencies market in business engineering acceptance

    OpenAIRE

    Catrina, Ioana; Neamtu, Ion

    2008-01-01

    In the current context, globalization involves awareness and action / reaction reporting of all social, political and economic level to the movement for creating unified market both regional and global. Globalization means the process by which distances between countries and continents including borders are not relevant in establishing and developing economic and socio-cultural cross-border relations. Thus, the relationships and dependencies acquire a potential support in an effort to capture...

  11. AIDS Epidemiyolojisi

    OpenAIRE

    SÜNTER, A.T.; PEKŞEN, Y.

    2010-01-01

    AIDS was first defined in the United States in 1981. It spreads to nearly all the countries of the world with a great speed and can infect everbody without any differantiation. The infection results in death and there is no cure or vaccine for it, yet. To data given to World Health Organization until July-1994, it is estimated that there are about 1 million patients and about 22 millions HIV positive persons In the world. Sixty percent of HIV positive persons are men and 40% are women. The di...

  12. Computer aided design and manufacturing of composite propfan blades for a cruise missile wind tunnel model

    Science.gov (United States)

    Thorp, Scott A.; Downey, Kevin M.

    1992-01-01

    One of the propulsion concepts being investigated for future cruise missiles is advanced unducted propfans. To support the evaluation of this technology applied to the cruise missile, a joint DOD and NASA test project was conducted to design and then test the characteristics of the propfans on a 0.55-scale, cruise missile model in a NASA wind tunnel. The configuration selected for study is a counterrotating rearward swept propfan. The forward blade row, having six blades, rotates in a counterclockwise direction, and the aft blade row, having six blades, rotates in a clockwise direction, as viewed from aft of the test model. Figures show the overall cruise missile and propfan blade configurations. The objective of this test was to evaluate propfan performance and suitability as a viable propulsion option for next generation of cruise missiles. This paper details the concurrent computer aided design, engineering, and manufacturing of the carbon fiber/epoxy propfan blades as the NASA Lewis Research Center.

  13. 14 CFR 221.141 - Method of revoking concurrence.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Method of revoking concurrence. 221.141... PROCEEDINGS) ECONOMIC REGULATIONS TARIFFS Giving and Revoking Concurrences to Carriers § 221.141 Method of revoking concurrence. (a) A concurrence may be revoked by filing with the Department a Notice of...

  14. 计算机辅助工程(CAE)技术的应用及其展望%Computer-aided Engineering (CAE) Technology and Its Prospects

    Institute of Scientific and Technical Information of China (English)

    曲春航

    2013-01-01

    At present, CAE is mainly used in the automotive, aerospace, electronics, civil engineering, general machinery, weap-ons, nuclear, oil and chemical industries. This paper discusses the development of CAE, CAE software introduces the types and applications, CAE algorithms and CAE technology's future development.%目前,CAE主要应用于汽车、航空、电子、土木工程、通用机械、兵器、核能、石油和化工等行业。该文主要论述了CAE的发展过程,介绍了CAE软件的种类和应用情况、CAE算法及CAE技术的未来发展。

  15. An Algorithm to Construct Concurrent Reachability Graph of Petri Nets

    Institute of Scientific and Technical Information of China (English)

    张金泉; 倪丽娜; 蒋昌俊

    2004-01-01

    Reachability graph is a very important tool to analyze the dynamic properties of Petri nets, but the concurrent relation of transitions in Petri nets cannot be represented by reachability graph. Petri net is a concurrent system, while reachability graph is a serial one. However, concurrency is a kind of property which is not only very significant but also difficult to be analyzed and controlled. This paper presents the concepts of concurrent reachable marking and concurrent reachable graph in order to represent and analyze the concurrent system. The algorithm constructing concurrent reachable marking set and concurrent reachability graph is also shown so that we can study the response problems among services in a network computing environment and analyze the throughput of the system. The Dining Philosophers Problem, which is a classic problem of describing the management of concurrent resources, is given as an example to illustrate the significance of concurrent reachability graph.

  16. Forum: Interaction of State Aid, Free Movement, Policy Competition and Abuse Control in Direct Tax Matters

    NARCIS (Netherlands)

    P.J. Wattel

    2013-01-01

    The European Union has woken up to State aid possibly contained in national direct tax measures. As a result, the number of Commission actions against Member States on the basis of fiscal State aid has increased in recent years, with some amazing results. It has also revealed overlap and concurrence

  17. Utilization of CAD/CAE for concurrent design of structural aircraft components

    Science.gov (United States)

    Kahn, William C.

    1993-01-01

    The feasibility of installing the Stratospheric Observatory for Infrared Astronomy telescope (named SOFIA) into an aircraft for NASA astronomy studies is investigated using CAD/CAE equipment to either design or supply data for every facet of design engineering. The aircraft selected for the platform was a Boeing 747, chosen on the basis of its ability to meet the flight profiles required for the given mission and payload. CAD models of the fuselage of two of the aircraft models studied (747-200 and 747 SP) were developed, and models for the component parts of the telescope and subsystems were developed by the various concurrent engineering groups of the SOFIA program, to determine the requirements for the cavity opening and for design configuration. It is noted that, by developing a plan to use CAD/CAE for concurrent engineering at the beginning of the study, it was possible to produce results in about two-thirds of the time required using traditional methods.

  18. Concurrent sourcing and external supplier opportunism

    DEFF Research Database (Denmark)

    Mols, Niels Peter

    When a firm simultaneously makes and buys the same components then the firm uses concurrent sourcing. This paper presents an agency model for explaining how and when concurrent sourcing reduces the likelihood of external supplier opportunism. In the proposed model, the external supplier’s expected...... costs of opportunism are determined as a product of four factors. The four factors are: likelihood of discovering supplier opportunism, buyer’s internalized quantity as reaction to supplier opportunism, asset specificity of external supplier’s investments, and multiplicator effects. Each...

  19. Models for concurrency: towards a classification

    DEFF Research Database (Denmark)

    Sassone, Vladimiro; Nielsen, Mogens; Winskel, Glynn

    1996-01-01

    Models for concurrency can be classified with respect to three relevant parameters: behaviour/ system, interleaving/noninterleaving, linear/branching time. When modelling a process, a choice concerning such parameters corresponds to choosing the level of abstraction of the resulting semantics. In...... this paper, we move a step towards a classification of models for concurrency based on the parameters above. Formally, we choose a representative of any of the eight classes of models obtained by varying the three parameters, and we study the formal relationships between them using the language of...

  20. Towards Interaction Reliability in Concurrent Applications

    Directory of Open Access Journals (Sweden)

    A. Silva

    2012-01-01

    Full Text Available Developing trustworthy concurrent applications is a seemingly never ending quest, which is necessary but difficult. It is necessary because mainstream systems and applications are inherently concurrent and they are pervasive to our daily life activities. It is difficult because such systems are inherently interactive and heterogeneous, so that boundaries can hardly be established for studying subsystems in isolation. Formal methods are a key instrument in resolving ambiguities and design reliable applications in a rigorous way. The authors overview major problems in the application of formal methods and outline how they are tackled by the papers collected in this volume.

  1. Notes on Timed Concurrent Constraint Programming

    DEFF Research Database (Denmark)

    Nielsen, Mogens; Valencia, Frank D.

    2004-01-01

    and program reactive systems. This note provides a comprehensive introduction to the background for and central notions from the theory of tccp. Furthermore, it surveys recent results on a particular tccp calculus, ntcc, and it provides a classification of the expressive power of various tccp languages.......A constraint is a piece of (partial) information on the values of the variables of a system. Concurrent constraint programming (ccp) is a model of concurrency in which agents (also called processes) interact by telling and asking information (constraints) to and from a shared store (a constraint...

  2. Concurrent Scheduling of Event-B Models

    CERN Document Server

    Boström, Pontus; Sere, Kaisa; Waldén, Marina; 10.4204/EPTCS.55.11

    2011-01-01

    Event-B is a refinement-based formal method that has been shown to be useful in developing concurrent and distributed programs. Large models can be decomposed into sub-models that can be refined semi-independently and executed in parallel. In this paper, we show how to introduce explicit control flow for the concurrent sub-models in the form of event schedules. We explore how schedules can be designed so that their application results in a correctness-preserving refinement step. For practical application, two patterns for schedule introduction are provided, together with their associated proof obligations. We demonstrate our method by applying it on the dining philosophers problem.

  3. Authentic And Concurrent Evaluation-refining

    DEFF Research Database (Denmark)

    Eriksson, Carina Ihlström; Åkesson, Maria; Kautz, Karlheinz

    2011-01-01

    This paper addresses the need for more detailed accounts for evaluation in design science research literature. By revisiting a design project regarding the future e-newspaper we give detailed descriptions of its authentic and concurrent evaluation approach by illustrating the what, why and how...... as well as decisions on strategic levels. We emphasize a holistic and concurrent approach to evaluation compared to the general design science research thinking and argue that reflecting on how to seek authenticity is important. By authenticity we refer to the notion of how closely an evaluation captures...

  4. AIDS.gov

    Science.gov (United States)

    ... concerns. Search Services Share This Help National HIV/AIDS Strategy Check out NHAS's latest progress in the ... from AIDS.gov Read more AIDS.gov tweets AIDS.gov HIV/AIDS Basics • Federal Resources • Using New ...

  5. Macroeconomic Issues in Foreign Aid

    DEFF Research Database (Denmark)

    Hjertholm, Peter; Laursen, Jytte; White, Howard

    foreign aid, macroeconomics of aid, gap models, aid fungibility, fiscal response models, foreign debt,......foreign aid, macroeconomics of aid, gap models, aid fungibility, fiscal response models, foreign debt,...

  6. HIV and AIDS

    Science.gov (United States)

    ... Got Homework? Here's Help White House Lunch Recipes HIV and AIDS KidsHealth > For Kids > HIV and AIDS ... actually the virus that causes the disease AIDS. HIV Hurts the Immune System People who are HIV ...

  7. Nosebleed, First Aid

    Science.gov (United States)

    ... and rashes clinical tools newsletter | contact Share | Nosebleed, First Aid A A A First Aid for Nosebleed: View ... of the nose, causing bleeding into the throat. First Aid Guide The following self-care measures are recommended: ...

  8. Splinter, First Aid

    Science.gov (United States)

    ... and rashes clinical tools newsletter | contact Share | Splinter, First Aid A A A First Aid for Splinter: View ... wet, it makes the area prone to infection. First Aid Guide Self-care measures to remove a splinter ...

  9. HIV-AIDS Connection

    Science.gov (United States)

    ... Content Marketing Share this: Main Content Area The HIV-AIDS Connection AIDS was first recognized in 1981 ... cancers. Why is there overwhelming scientific consensus that HIV causes AIDS? Before HIV infection became widespread in ...

  10. Heart attack first aid

    Science.gov (United States)

    First aid - heart attack; First aid - cardiopulmonary arrest; First aid - cardiac arrest ... A heart attack occurs when the blood flow that carries oxygen to the heart is blocked. The heart muscle ...

  11. Logics and Games for True Concurrency

    CERN Document Server

    Gutierrez, Julian

    2010-01-01

    We study the underlying mathematical properties of various partial order models of concurrency based on transition systems, Petri nets, and event structures, and show that the concurrent behaviour of these systems can be captured in a uniform way by two simple and general dualities of local behaviour. Such dualities are used to define new mu-calculi and logic games for the analysis of concurrent systems with partial order semantics. Some results of this work are: the definition of a number of mu-calculi which, in some classes of systems, induce the same identifications as some of the best known bisimulation equivalences for concurrency; and the definition of (infinite) higher-order logic games for bisimulation and model-checking, where the players of the games are given (local) monadic second-order power on the sets of elements they are allowed to play. More specifically, we show that our games are sound and complete, and therefore, determined; moreover, they are decidable in the finite case and underpin nove...

  12. Formal Derivation of Concurrent Garbage Collectors

    NARCIS (Netherlands)

    Pavlovic, Dusko; Pepper, Peter; Smith, Douglas R.

    2010-01-01

    Concurrent garbage collectors are notoriously difficult to implement correctly. Previous approaches to the issue of producing correct collectors have mainly been based on posit-and-prove verification or on the application of domain-specific templates and transformations. We show how to derive the up

  13. On run-time exploitation of concurrency

    NARCIS (Netherlands)

    Hölzenspies, Philip Kaj Ferdinand

    2010-01-01

    The `free' speed-up stemming from ever increasing processor speed is over. Performance increase in computer systems can now only be achieved through parallelism. One of the biggest challenges in computer science is how to map applications onto parallel computers. Concurrency, seen as the set of v

  14. Integrated concurrent utilization quality review, Part one.

    Science.gov (United States)

    Caterinicchio, R P

    1987-01-01

    This article is the first of a two-part series which argues for the concurrent management of the appropriateness, necessity, and quality of patient care. Intensifying scrutiny by the credentialing groups, the PROs and all third-party payors underscores the vital need to implement cost-effective information systems which integrate the departmentalized functions of patient-physician profiling, DRG case-mix analyses, length of stay monitoring, pre-admission/admission and continued stay review, discharge planning, risk management, incident reporting and quality review. In the domain of physician performance regarding admitting and practice patterns, the ability to exercise concurrent utilization-quality review means early detection and prevention of events which would otherwise result in denials of payment and/or compromised patient care. Concurrent utilization-quality review must, by definition, be managerially invasive and focused; hence, it is integral to maintaining the integrity of the services and product lines offered by the provider. In fact, if PPO status is a marketing agenda, then the institutional objectives of cost-effectiveness, productivity, value, and competitiveness can only be achieved through concurrent utilization-quality review.

  15. Concurrent Meta-Evaluation: A Critique

    Science.gov (United States)

    Hanssen, Carl E.; Lawrenz, Frances; Dunet, Diane O.

    2008-01-01

    Meta-evaluations reported in the literature, although rare, often have focused on retrospective assessment of completed evaluations. Conducting a meta-evaluation concurrently with the evaluation modifies this approach. This method provides the opportunity for the meta-evaluators to advise the evaluators and provides the basis for a summative…

  16. Collaborative Engineering Paradigm Applied to the Aerospace Industry

    OpenAIRE

    Mas Morate, Fernando; Menéndez Cuñado, José Luis; Oliva Olvera, Manuel; Gómez, Alejandro; Ríos Chueco, José

    2013-01-01

    Airbus designs and industrializes aircrafts using Concurrent Engineering techniques since decades. The introduction of new PLM methods, procedures and tools, and the need to reduce time-to-market, led Airbus Military to pursue new working methods. Traditional Engineering works sequentially. Concurrent Engineering basically overlaps tasks between teams. Collaborative Engineering promotes teamwork to develop product, processes and resources from the conceptual phase to the start of the seria...

  17. System Engineering Process Realization Toolkit Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA faces many systems engineering challenges as it seeks to conduct exploration and science missions concurrently. One such challenge is implementing a repeatable...

  18. Cell Cycle Regulates Nuclear Stability of AID and Determines the Cellular Response to AID.

    Directory of Open Access Journals (Sweden)

    Quy Le

    2015-09-01

    Full Text Available AID (Activation Induced Deaminase deaminates cytosines in DNA to initiate immunoglobulin gene diversification and to reprogram CpG methylation in early development. AID is potentially highly mutagenic, and it causes genomic instability evident as translocations in B cell malignancies. Here we show that AID is cell cycle regulated. By high content screening microscopy, we demonstrate that AID undergoes nuclear degradation more slowly in G1 phase than in S or G2-M phase, and that mutations that affect regulatory phosphorylation or catalytic activity can alter AID stability and abundance. We directly test the role of cell cycle regulation by fusing AID to tags that destabilize nuclear protein outside of G1 or S-G2/M phases. We show that enforced nuclear localization of AID in G1 phase accelerates somatic hypermutation and class switch recombination, and is well-tolerated; while nuclear AID compromises viability in S-G2/M phase cells. We identify AID derivatives that accelerate somatic hypermutation with minimal impact on viability, which will be useful tools for engineering genes and proteins by iterative mutagenesis and selection. Our results further suggest that use of cell cycle tags to regulate nuclear stability may be generally applicable to studying DNA repair and to engineering the genome.

  19. Transactions Concurrency Control in Web Service Environment

    DEFF Research Database (Denmark)

    Alrifai, Mohammad; Dolog, Peter; Nejdl, Wolfgang

    2006-01-01

    concurrent access to web service resources and data. In this paper we propose an extension to the WS-Transaction Protocol which ensures the consistency of the data when independent business transactions access the data concurrently under the relaxed transaction properties. Our extension is based......Business transactions in web service environments run with relaxed isolation and atomicity property. In such environments, transactions can commit and roll back independently on each other. Transaction management has to reflect this issue and address the problems which result for example from...... on transaction dependency graphs maintained at the service provider side. We have implemented such a protocol on top of WS-Transaction. The extension on the web service provider side is simple to achieve as it can be an integral part of the service invocation mechanism. It has also an advantage from...

  20. A Framework of Concurrent Mechanism Based on Java Multithread

    Directory of Open Access Journals (Sweden)

    Wuxue Jiang

    2013-09-01

    Full Text Available The continuously increased demand for paralleling multitask in domains such as grid computing and cloud computing has significantly promoted research on concurrent mechanism and concurrent programming. The Java programming language supports multithread mechanism for developing paralleling programs, however, it is difficult to apply Java concurrent primitives to specific problems. Thus, for the development of high reliable and qualitative Java concurrent programs, this paper analyses Java multithread mechanism and it’s realization, studies the concurrent mechanism based on Java synchronization and interactive communication mechanism , compares the concurrent structure based on operating system and based on Java multithread, sums up some concurrent programming rules and strategies to prevent deadlock. A frame instance based on entire synchronization is presented, which can help to develop concurrent programs quickly.  

  1. Construction disputes in Denmark: the case of concurrent delay

    DEFF Research Database (Denmark)

    Cavaleri, Sylvie Cécile

    2015-01-01

    Through a case study of decisions on concurrent delay, the article discusses the defining features of Danish construction arbitration.......Through a case study of decisions on concurrent delay, the article discusses the defining features of Danish construction arbitration....

  2. Concurrent Composition and Algebras of Events, Actions, and Processes

    CERN Document Server

    Burgin, Mark

    2008-01-01

    There are many different models of concurrent processes. The goal of this work is to introduce a common formalized framework for current research in this area and to eliminate shortcomings of existing models of concurrency. Following up the previous research of the authors and other researchers on concurrency, here we build a high-level metamodel EAP (event-action-process) for concurrent processes. This metamodel comprises a variety of other models of concurrent processes. We shape mathematical models for, and study events, actions, and processes in relation to important practical problems, such as communication in networks, concurrent programming, and distributed computations. In the third section of the work, a three-level algebra of events, actions and processes is constructed and studied as a new stage of algebra for concurrent processes. Relations between EAP process algebra and other models of concurrency are considered in the fourth section of this work.

  3. Concurrency Control Mechanism of Complex Objects

    Institute of Scientific and Technical Information of China (English)

    徐庆云; 王能斌

    1992-01-01

    A complex object is an abstraction and description of a complex entity of the real world.Many applications in such domains as CIMS,CAD and OA define and manipulate a complex object as a single unit.In this paper,a definition of the model of complex objects is given,and the concurrency control mechanism of complex objects in WHYMX object-oriented database system is described.

  4. Using Molecular Biology to Maximize Concurrent Training

    OpenAIRE

    Baar, Keith

    2014-01-01

    Very few sports use only endurance or strength. Outside of running long distances on a flat surface and power-lifting, practically all sports require some combination of endurance and strength. Endurance and strength can be developed simultaneously to some degree. However, the development of a high level of endurance seems to prohibit the development or maintenance of muscle mass and strength. This interaction between endurance and strength is called the concurrent training effect. This revie...

  5. Aid and Development

    DEFF Research Database (Denmark)

    Tarp, Finn

    Foreign aid looms large in the public discourse; and international development assistance remains squarely on most policy agendas concerned with growth, poverty and inequality in Africa and elsewhere in the developing world. The present review takes a retrospective look at how foreign aid has...... evolved since World War II in response to a dramatically changing global political and economic context. I review the aid process and associated trends in the volume and distribution of aid and categorize some of the key goals, principles and institutions of the aid system. The evidence on whether aid has...... for aid in the future...

  6. Types of Foreign Aid

    DEFF Research Database (Denmark)

    Bjørnskov, Christian

    Foreign aid is given for many purposes and different intentions, yet most studies treat aid flows as a unitary concept. This paper uses factor analysis to separate aid flows into different types. The main types can be interpreted as aid for economic purposes, social purposes, and reconstruction......; a residual category captures remaining purposes. Estimating the growth effects of separable types of aid suggests that most aid has no effects while reconstruction aid has direct positive effects. Although this type only applies in special circumstances, it has become more prevalent in more recent years....

  7. Unusual Necrotizing Encephalitis in Raccoons and Skunks Concurrently Infected With Canine Distemper Virus and Sarcocystis sp.

    Science.gov (United States)

    Kubiski, S V; Sisó, S; Church, M E; Cartoceti, A N; Barr, B; Pesavento, P A

    2016-05-01

    Canine distemper virus commonly infects free-ranging, terrestrial mesopredators throughout the United States. Due to the immunosuppressive effects of the virus, concurrent opportunistic infections are also common. Among these, secondary systemic protozoal infections have been described in a number of species. We report an unusual presentation of necrotizing encephalitis associated withSarcocystissp in four raccoons and one skunk concurrently infected with canine distemper virus. Lesions were characterized by variably sized necrotizing cavitations composed of abundant mineral admixed with inflammatory cells and protozoa.Sarcocystissp was confirmed via immunohistochemistry using a monoclonal antibody toSarcocystis neurona The pathologic changes are similar to lesions in human AIDS patients infected withToxoplasma gondii. PMID:26374278

  8. Managing Asynchronous Data in ATLAS's Concurrent Framework

    CERN Document Server

    Leggett, Charles; The ATLAS collaboration

    2016-01-01

    In order to be able to make effective use of emerging hardware, where the amount of memory available to any CPU is rapidly decreasing as the core count continues to rise, ATLAS has begun a migration to a concurrent, multi-threaded software framework, known as AthenaMT. Significant progress has been made in implementing AthenaMT - we can currently run realistic Geant4 simulations on massively concurrent machines. the migration of realistic prototypes of reconstruction workflows is more difficult, given the large amounts of legacy code and the complexity and challenges of reconstruction software. These types of workflows, however, are the types that will most benefit from the memory reduction features of a multi-threaded framework. One of the challenges that we will report on in this paper is the re-design and implementation of several key asynchronous technologies whose behaviour is radically different in a concurrent environment than in a serial one, namely the management of Conditions data and the Detector D...

  9. Orthomodular Lattices Induced by the Concurrency Relation

    Directory of Open Access Journals (Sweden)

    Luca Bernardinello

    2009-11-01

    Full Text Available We apply to locally finite partially ordered sets a construction which associates a complete lattice to a given poset; the elements of the lattice are the closed subsets of a closure operator, defined starting from the concurrency relation. We show that, if the partially ordered set satisfies a property of local density, i.e.: N-density, then the associated lattice is also orthomodular. We then consider occurrence nets, introduced by C.A. Petri as models of concurrent computations, and define a family of subsets of the elements of an occurrence net; we call those subsets "causally closed" because they can be seen as subprocesses of the whole net which are, intuitively, closed with respect to the forward and backward local state changes. We show that, when the net is K-dense, the causally closed sets coincide with the closed sets induced by the closure operator defined starting from the concurrency relation. K-density is a property of partially ordered sets introduced by Petri, on the basis of former axiomatizations of special relativity theory.

  10. A Framework of Concurrent Mechanism Based on Java Multithread

    OpenAIRE

    Wuxue Jiang; Qi Li; Zhiming Wang; Jianfeng Luo

    2013-01-01

    The continuously increased demand for paralleling multitask in domains such as grid computing and cloud computing has significantly promoted research on concurrent mechanism and concurrent programming. The Java programming language supports multithread mechanism for developing paralleling programs, however, it is difficult to apply Java concurrent primitives to specific problems. Thus, for the development of high reliable and qualitative Java concurrent programs, this paper analyses Java mult...

  11. Thinking about Aid Predictability

    OpenAIRE

    Andrews, Matthew; Wilhelm, Vera

    2008-01-01

    Researchers are giving more attention to aid predictability. In part, this is because of increases in the number of aid agencies and aid dollars and the growing complexity of the aid community. A growing body of research is examining key questions: Is aid unpredictable? What causes unpredictability? What can be done about it? This note draws from a selection of recent literature to bring s...

  12. How to Get Hearing Aids

    Science.gov (United States)

    ... Consumer Products Hearing Aids How to get Hearing Aids Share Tweet Linkedin Pin it More sharing options ... my hearing aids? How do I get hearing aids? To get hearing aids, you should first have ...

  13. ELAS - SCIENCE & TECHNOLOGY LABORATORY APPLICATIONS SOFTWARE (CONCURRENT VERSION)

    Science.gov (United States)

    Pearson, R. W.

    1994-01-01

    The Science and Technology Laboratory Applications Software (ELAS) was originally designed to analyze and process digital imagery data, specifically remotely-sensed scanner data. This capability includes the processing of Landsat multispectral data; aircraft-acquired scanner data; digitized topographic data; and numerous other ancillary data, such as soil types and rainfall information, that can be stored in digitized form. ELAS has the subsequent capability to geographically reference this data to dozens of standard, as well as user created projections. As an integrated image processing system, ELAS offers the user of remotely-sensed data a wide range of capabilities in the areas of land cover analysis and general purpose image analysis. ELAS is designed for flexible use and operation and includes its own FORTRAN operating subsystem and an expandable set of FORTRAN application modules. Because all of ELAS resides in one "logical" FORTRAN program, data inputs and outputs, directives, and module switching are convenient for the user. There are over 230 modules presently available to aid the user in performing a wide range of land cover analyses and manipulation. The file management modules enable the user to allocate, define, access, and specify usage for all types of files (ELAS files, subfiles, external files etc.). Various other modules convert specific types of satellite, aircraft, and vector-polygon data into files that can be used by other ELAS modules. The user also has many module options which aid in displaying image data, such as magnification/reduction of the display; true color display; and several memory functions. Additional modules allow for the building and manipulation of polygonal areas of the image data. Finally, there are modules which allow the user to select and classify the image data. An important feature of the ELAS subsystem is that its structure allows new applications modules to be easily integrated in the future. ELAS has as a standard

  14. Electronics Engineering Department Thrust Area report FY'84

    Energy Technology Data Exchange (ETDEWEB)

    Minichino, C.; Phelps, P.L. (eds.)

    1984-01-01

    This report describes the work of the Electronics Engineering Department Thrust Areas for FY'84: diagnostics and microelectronic engineering; signal and control engineering; microwave and pulsed power engineering; computer-aided engineering; engineering modeling and simulation; and systems engineering. For each Thrust Area, an overview and a description of the goals and achievements of each project is provided.

  15. Electronics Engineering Department Thrust Area report FY'84

    International Nuclear Information System (INIS)

    This report describes the work of the Electronics Engineering Department Thrust Areas for FY'84: diagnostics and microelectronic engineering; signal and control engineering; microwave and pulsed power engineering; computer-aided engineering; engineering modeling and simulation; and systems engineering. For each Thrust Area, an overview and a description of the goals and achievements of each project is provided

  16. Engineering creativity by using computer aided Mindmap

    OpenAIRE

    Imran Mahmud

    2013-01-01

    Creativity is a high-level cognitive process which has given rise to research in various fields such as education. This paper shows a research on how Mind Mapping helps tertiary level students in Bangladesh to explore their creativity. It also focuses on use of Mind mapping in a learning environment which requires an enhanced way of thinking, learning and presenting. A research framework and a conceptual framework were developed to conduct this research. Based on the framework a case study wi...

  17. Engineering creativity by using computer aided Mindmap

    Directory of Open Access Journals (Sweden)

    Imran Mahmud

    2013-07-01

    Full Text Available Creativity is a high-level cognitive process which has given rise to research in various fields such as education. This paper shows a research on how Mind Mapping helps tertiary level students in Bangladesh to explore their creativity. It also focuses on use of Mind mapping in a learning environment which requires an enhanced way of thinking, learning and presenting. A research framework and a conceptual framework were developed to conduct this research. Based on the framework a case study will be followed by a qualitative and quantitative study on a group of students. The case study aims to compare student’s performance before the use of mind map and the change after using it. Result of the research shows that use of Mind Mapping enhances the learning capacity in terms of number of ideas generated as well as improves presentation focus.. This research paper will facilitate the students, teachers and the researchers who seek ways to enhance the tertiary level educational experience.

  18. Creating components object oriented, concurrent, and distributed computing in Java

    CERN Document Server

    Kann, Charles W

    2003-01-01

    INTRODUCTION TO CONCURRENT PROGRAMMING AND COMPONENTSChapter GoalsWhat is Concurrent Programming?ComponentsTypes of Concurrent ProgrammingTHREADS AND PROGRAM CONTEXTSWriting threads in JavaA Simple Execution ModelProgram SafetyDeadlockDESIGNING AND IMPLEMENTING CONCURRENT PROGRAMS WITH STATE DIAGRAMSBackgroundSteps to Create a Concurrent ProgramThe Producer/Consumer ProblemWhy Passive Objects are ComponentsGas Station Simulation ProblemIdentifiers, Variables, Objects, and Collection ClassesIdentifiers and VariablesJava Identifiers and VariablesPrimitivesObjectsCollection Classes in JavaPROGRAM

  19. Analyzing and designing object-oriented missile simulations with concurrency

    Science.gov (United States)

    Randorf, Jeffrey Allen

    2000-11-01

    A software object model for the six degree-of-freedom missile modeling domain is presented. As a precursor, a domain analysis of the missile modeling domain was started, based on the Feature-Oriented Domain Analysis (FODA) technique described by the Software Engineering Institute (SEI). It was subsequently determined the FODA methodology is functionally equivalent to the Object Modeling Technique. The analysis used legacy software documentation and code from the ENDOSIM, KDEC, and TFrames 6-DOF modeling tools, including other technical literature. The SEI Object Connection Architecture (OCA) was the template for designing the object model. Three variants of the OCA were considered---a reference structure, a recursive structure, and a reference structure with augmentation for flight vehicle modeling. The reference OCA design option was chosen for maintaining simplicity while not compromising the expressive power of the OMT model. The missile architecture was then analyzed for potential areas of concurrent computing. It was shown how protected objects could be used for data passing between OCA object managers, allowing concurrent access without changing the OCA reference design intent or structure. The implementation language was the 1995 release of Ada. OCA software components were shown how to be expressed as Ada child packages. While acceleration of several low level and other high operations level are possible on proper hardware, there was a 33% degradation of 4th order Runge-Kutta integrator performance of two simultaneous ordinary differential equations using Ada tasking on a single processor machine. The Defense Department's High Level Architecture was introduced and explained in context with the OCA. It was shown the HLA and OCA were not mutually exclusive architectures, but complimentary. HLA was shown as an interoperability solution, with the OCA as an architectural vehicle for software reuse. Further directions for implementing a 6-DOF missile modeling

  20. Aid and growth regressions

    DEFF Research Database (Denmark)

    Hansen, Henrik; Tarp, Finn

    2001-01-01

    This paper examines the relationship between foreign aid and growth in real GDP per capita as it emerges from simple augmentations of popular cross country growth specifications. It is shown that aid in all likelihood increases the growth rate, and this result is not conditional on ‘good’ policy....... There are, however, decreasing returns to aid, and the estimated effectiveness of aid is highly sensitive to the choice of estimator and the set of control variables. When investment and human capital are controlled for, no positive effect of aid is found. Yet, aid continues to impact on growth via...

  1. Armored Geomembrane Cover Engineering

    Directory of Open Access Journals (Sweden)

    Kevin Foye

    2011-06-01

    Full Text Available Geomembranes are an important component of modern engineered barriers to prevent the infiltration of stormwater and runoff into contaminated soil and rock as well as waste containment facilities—a function generally described as a geomembrane cover. This paper presents a case history involving a novel implementation of a geomembrane cover system. Due to this novelty, the design engineers needed to assemble from disparate sources the design criteria for the engineering of the cover. This paper discusses the design methodologies assembled by the engineering team. This information will aid engineers designing similar cover systems as well as environmental and public health professionals selecting site improvements that involve infiltration barriers.

  2. Integrative metabolic engineering

    Directory of Open Access Journals (Sweden)

    George H McArthur IV

    2015-07-01

    Full Text Available Recent advances in experimental and computational synthetic biology are extremely useful for achieving metabolic engineering objectives. The integration of synthetic biology and metabolic engineering within an iterative design-build-test framework will improve the practice of metabolic engineering by relying more on efficient design strategies. Computational tools that aid in the design and in silico simulation of metabolic pathways are especially useful. However, software helpful for constructing, implementing, measuring and characterizing engineered pathways and networks should not be overlooked. In this review, we highlight computational synthetic biology tools relevant to metabolic engineering, organized in the context of the design-build-test cycle.

  3. Concurrent conditional clustering of multiple networks: COCONETS.

    Directory of Open Access Journals (Sweden)

    Sabrina Kleessen

    Full Text Available The accumulation of high-throughput data from different experiments has facilitated the extraction of condition-specific networks over the same set of biological entities. Comparing and contrasting of such multiple biological networks is in the center of differential network biology, aiming at determining general and condition-specific responses captured in the network structure (i.e., included associations between the network components. We provide a novel way for comparison of multiple networks based on determining network clustering (i.e., partition into communities which is optimal across the set of networks with respect to a given cluster quality measure. To this end, we formulate the optimization-based problem of concurrent conditional clustering of multiple networks, termed COCONETS, based on the modularity. The solution to this problem is a clustering which depends on all considered networks and pinpoints their preserved substructures. We present theoretical results for special classes of networks to demonstrate the implications of conditionality captured by the COCONETS formulation. As the problem can be shown to be intractable, we extend an existing efficient greedy heuristic and applied it to determine concurrent conditional clusters on coexpression networks extracted from publically available time-resolved transcriptomics data of Escherichia coli under five stresses as well as on metabolite correlation networks from metabolomics data set from Arabidopsis thaliana exposed to eight environmental conditions. We demonstrate that the investigation of the differences between the clustering based on all networks with that obtained from a subset of networks can be used to quantify the specificity of biological responses. While a comparison of the Escherichia coli coexpression networks based on seminal properties does not pinpoint biologically relevant differences, the common network substructures extracted by COCONETS are supported by

  4. Concurrency control in distributed database systems

    CERN Document Server

    Cellary, W; Gelenbe, E

    1989-01-01

    Distributed Database Systems (DDBS) may be defined as integrated database systems composed of autonomous local databases, geographically distributed and interconnected by a computer network.The purpose of this monograph is to present DDBS concurrency control algorithms and their related performance issues. The most recent results have been taken into consideration. A detailed analysis and selection of these results has been made so as to include those which will promote applications and progress in the field. The application of the methods and algorithms presented is not limited to DDBSs but a

  5. Concurrent Kimura disease and lupus nephritis

    Science.gov (United States)

    Wang, Haitao; Fang, Fang; Sun, Ying; Wang, Songlan; Mao, Yonghui

    2016-01-01

    Abstract Background: Kimura disease is a rare chronic inflammatory disorder with peripheral eosinophilia and elevated serum IgE and is also frequently complicated by nephropathy. Methods: We report a rare case of Kimura disease concomitant with lupus nephritis in a 72-year old male patient with recurrent unexplained lymphadenopathy, renal lesions, and immunologic abnormalities. Results: The patient was successfully managed with gamma immunoglobulin, intravenous pulse methylprednisolone therapy, hydroxychloroquine, and prednisone. Conclusion: This is the first report of a case of Kimura disease concomitant with lupus nephritis and highlights the importance of considering lupus nephritis as a possible concurrent disease in patients with Kimura disease that have immunologic abnormalities. PMID:27741124

  6. Reliability-based concurrent subspace optimization method

    Institute of Scientific and Technical Information of China (English)

    FAN Hui; LI Wei-ji

    2008-01-01

    To avoid the high computational cost and much modification in the process of applying traditional re-liability-based design optimization method, a new reliability-based concurrent subspace optimization approach is proposed based on the comparison and analysis of the existing muhidisciplinary optimization techniques and reli-ability assessment methods. It is shown through a canard configuration optimization for a three-surface transport that the proposed method is computationally efficient and practical with the least modification to the current de-terministic optimization process.

  7. How HIV Causes AIDS

    Science.gov (United States)

    ... Share this: Main Content Area How HIV Causes AIDS HIV destroys CD4 positive (CD4+) T cells, which ... and disease, ultimately resulting in the development of AIDS. Most people who are infected with HIV can ...

  8. HIV/AIDS Basics

    Science.gov (United States)

    ... Providers Prevention Resources Newsletter Get Tested Find an HIV testing site near you. Enter ZIP code or ... AIDS Get Email Updates on AAA Anonymous Feedback HIV/AIDS Media Infographics Syndicated Content Podcasts Slide Sets ...

  9. Aids for visual impairment.

    OpenAIRE

    Dudley, N. J.

    1990-01-01

    This article provides only a flavour of the type and range of aids available to the visually impaired person. Many other aids for leisure, learning, and daily living are illustrated in the RNIB equipment and games catalogue.

  10. Head injury - first aid

    Science.gov (United States)

    ... medlineplus.gov/ency/article/000028.htm Head injury - first aid To use the sharing features on this page, ... a concussion can range from mild to severe. First Aid Learning to recognize a serious head injury and ...

  11. Poisoning first aid

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/007579.htm Poisoning first aid To use the sharing features on this page, ... or burns Stupor Unconsciousness Unusual breath odor Weakness First Aid Seek immediate medical help. For poisoning by swallowing: ...

  12. Frostbite, First Aid

    Science.gov (United States)

    ... and rashes clinical tools newsletter | contact Share | Frostbite, First Aid A A A Severe frostbite can result in ... became frozen). Frostbite is often associated with hypothermia. First Aid Guide In the case of mild frostbite, the ...

  13. Jellyfish Stings, First Aid

    Science.gov (United States)

    ... rashes clinical tools newsletter | contact Share | Jellyfish Stings, First Aid A A A The rash caused by a ... to Portuguese man-of-war stings as well. First Aid Guide The rescuer should take care to avoid ...

  14. Unconsciousness, First Aid

    Science.gov (United States)

    ... and rashes clinical tools newsletter | contact Share | Unconsciousness, First Aid A A A Unconsciousness signs and symptoms can ... keep the airway clear while awaiting medical care. First Aid Guide If you find an unconscious person, try ...

  15. Tick Bites, First Aid

    Science.gov (United States)

    ... rashes clinical tools newsletter | contact Share | Tick Bites, First Aid A A A It is important to inspect ... temporary paralysis in their host (called tick paralysis). First Aid Guide To remove an embedded tick: Wash your ...

  16. Heat Cramps, First Aid

    Science.gov (United States)

    ... rashes clinical tools newsletter | contact Share | Heat Cramps, First Aid A A A Heat cramp signs and symptoms ... if later stages of heat illness are suspected. First Aid Guide Use a combination of the following measures, ...

  17. Blisters, First Aid

    Science.gov (United States)

    ... and rashes clinical tools newsletter | contact Share | Blisters, First Aid A A A Blisters on the feet are ... can also be found via the Disease List. First Aid Guide Blisters often go away on their own ...

  18. Heatstroke, First Aid

    Science.gov (United States)

    ... and rashes clinical tools newsletter | contact Share | Heatstroke, First Aid A A A Heatstroke signs and symptoms can ... specific to the earlier stages of heat illness. First Aid Guide When heatstroke is suspected, seek emergency medical ...

  19. Heat Exhaustion, First Aid

    Science.gov (United States)

    ... rashes clinical tools newsletter | contact Share | Heat Exhaustion, First Aid A A A Heat exhaustion signs and symptoms ... specific to the other stages of heat illness. First Aid Guide Use a combination of the following measures ...

  20. First aid kit

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/001958.htm First aid kit To use the sharing features on this ... ahead, you can create a well-stocked home first aid kit. Keep all of your supplies in one ...

  1. Head Trauma, First Aid

    Science.gov (United States)

    ... rashes clinical tools newsletter | contact Share | Head Trauma, First Aid A A A Head trauma signs and symptoms ... to take care for potential neck/spinal injury. First Aid Guide If you suspect either a serious head ...

  2. Bruises, First Aid

    Science.gov (United States)

    ... and rashes clinical tools newsletter | contact Share | Bruises, First Aid A A A Bruises lighten and change color ... Bruises can be a sign of internal bleeding. First Aid Guide If there is external bleeding in addition ...

  3. First Aid and Safety

    Science.gov (United States)

    ... Things to Know About Zika & Pregnancy First Aid & Safety Keeping your child safe is your top priority. ... to call for help, and more. First Aid & Safety Center Home Sweet Home A Safe and Spooktacular ...

  4. AIDS Myths and Misunderstandings

    Science.gov (United States)

    ... 2014 Select a Language: Fact Sheet 158 AIDS Myths and Misunderstandings WHY ARE THERE SO MANY AIDS ... sweat, saliva or urine of an infected person. Myth: A pregnant woman with HIV infection always infects ...

  5. First Aid: Influenza (Flu)

    Science.gov (United States)

    ... Smoothie Pregnant? Your Baby's Growth First Aid: The Flu KidsHealth > For Parents > First Aid: The Flu Print ... tiredness What to Do If Your Child Has Flu Symptoms: Call your doctor. Encourage rest. Keep your ...

  6. Music and Hearing Aids

    OpenAIRE

    Madsen, Sara M. K.; Moore, Brian C. J.

    2014-01-01

    The signal processing and fitting methods used for hearing aids have mainly been designed to optimize the intelligibility of speech. Little attention has been paid to the effectiveness of hearing aids for listening to music. Perhaps as a consequence, many hearing-aid users complain that they are not satisfied with their hearing aids when listening to music. This issue inspired the Internet-based survey presented here. The survey was designed to identify the nature and prevalence of problems a...

  7. Fiscal effects of aid

    OpenAIRE

    Timmis, Emilija

    2015-01-01

    This thesis analyses fiscal effects of aid, first of health aid on health spending for a sample of developing countries and then broadly for Ethiopia and Tanzania. Particular attention is paid to data quality and the severe difficulties in achieving a reliable disaggregation of aid into its on-budget and off-budget components. The first essay assesses the sensitivity of estimated health aid fungibility to how the missing data (often considerable) are treated and explores a novel (at least in...

  8. Studying Aid: Some Methods

    OpenAIRE

    Gasper, Des

    2003-01-01

    textabstractINVESTIGATING IDEAS, IDEOLOGIES AND PRACTICES This paper presents some methods for trying to make sense of international aid and of its study.1 Some of the methods may be deemed ethnographic; the others are important partners to them, but rather different. In the course of discussing questions of aid policy and practice—such as: Should international development aid exist at all? How should aid be conducted? Should humanitarian relief be provided in conflict situations when it can ...

  9. Concurrent initialization for Bearing-Only SLAM.

    Science.gov (United States)

    Munguía, Rodrigo; Grau, Antoni

    2010-01-01

    Simultaneous Localization and Mapping (SLAM) is perhaps the most fundamental problem to solve in robotics in order to build truly autonomous mobile robots. The sensors have a large impact on the algorithm used for SLAM. Early SLAM approaches focused on the use of range sensors as sonar rings or lasers. However, cameras have become more and more used, because they yield a lot of information and are well adapted for embedded systems: they are light, cheap and power saving. Unlike range sensors which provide range and angular information, a camera is a projective sensor which measures the bearing of images features. Therefore depth information (range) cannot be obtained in a single step. This fact has propitiated the emergence of a new family of SLAM algorithms: the Bearing-Only SLAM methods, which mainly rely in especial techniques for features system-initialization in order to enable the use of bearing sensors (as cameras) in SLAM systems. In this work a novel and robust method, called Concurrent Initialization, is presented which is inspired by having the complementary advantages of the Undelayed and Delayed methods that represent the most common approaches for addressing the problem. The key is to use concurrently two kinds of feature representations for both undelayed and delayed stages of the estimation. The simulations results show that the proposed method surpasses the performance of previous schemes. PMID:22294884

  10. Concurrent Initialization for Bearing-Only SLAM

    Directory of Open Access Journals (Sweden)

    Antoni Grau

    2010-03-01

    Full Text Available Simultaneous Localization and Mapping (SLAM is perhaps the most fundamental problem to solve in robotics in order to build truly autonomous mobile robots. The sensors have a large impact on the algorithm used for SLAM. Early SLAM approaches focused on the use of range sensors as sonar rings or lasers. However, cameras have become more and more used, because they yield a lot of information and are well adapted for embedded systems: they are light, cheap and power saving. Unlike range sensors which provide range and angular information, a camera is a projective sensor which measures the bearing of images features. Therefore depth information (range cannot be obtained in a single step. This fact has propitiated the emergence of a new family of SLAM algorithms: the Bearing-Only SLAM methods, which mainly rely in especial techniques for features system-initialization in order to enable the use of bearing sensors (as cameras in SLAM systems. In this work a novel and robust method, called Concurrent Initialization, is presented which is inspired by having the complementary advantages of the Undelayed and Delayed methods that represent the most common approaches for addressing the problem. The key is to use concurrently two kinds of feature representations for both undelayed and delayed stages of the estimation. The simulations results show that the proposed method surpasses the performance of previous schemes.

  11. Concurrent bilateral ectopic pregnancy: a rarity

    Directory of Open Access Journals (Sweden)

    Prabhleen Kaur

    2015-08-01

    Full Text Available Bilateral ectopic pregnancy is a rare twin gestation with only a few cases reported in the literature. We report a 30 year old woman without any high risk factor for ectopic pregnancy, who had concurrent bilateral ectopic pregnancy. A 30 year old female presented to the Gynecology emergency department complaining of vaginal bleeding and abdominal pain. The presumptive diagnosis of ruptured left sided ectopic pregnancy was made on basis of clinical findings and ultrasound finings. An emergency laparotomy was done revealed a hemoperitoneum of 1.5 liters, a ruptured left tubal pregnancy with active bleeding and right tubal un-ruptured ectopic was found. A bilateral salpingectomy was performed. Histopathology confirmed presence of chorionic villi in both tubes. In theory, laparoscopic salpingostomy is the best surgical approach in bilateral tubal pregnancy. However, bilateral salpingectomy may be necessary when both tubes are extensively damaged or are actively bleeding. Successful pregnancies have been reported after conservative surgical treatment of bilateral ectopic, but the risk of recurrence is high. Our decision for an emergency laparotomy followed by bilateral salpingectomy was based on the fact that the patient presented with acute abdomen and was haemodynamically unstable and there was extensive bilateral tubal damage. As the incidence of ectopic pregnancies is increasing concurrently with the incidences of pelvic inflammatory disease and use of assisted fertility techniques; it may be that these and ldquo;rare ectopics and rdquo; will become less uncommon. [Int J Reprod Contracept Obstet Gynecol 2015; 4(4.000: 1197-1199

  12. Determinants of State Aid

    NARCIS (Netherlands)

    Buiren, K.; Brouwer, E.

    2010-01-01

    From economic theory we derive a set of hypotheses on the determination of state aid. Econometric analysis on EU state aid panel data is carried out to test whether the determinants we expect on the basis of theory, correspond to the occurrence of state aid in practice in the EU. We find that politi

  13. First Aid: Falls

    Science.gov (United States)

    ... Story" 5 Things to Know About Zika & Pregnancy First Aid: Falls KidsHealth > For Parents > First Aid: Falls Print A A A Text Size en ... Floors, Doors & Windows, Furniture, Stairways: Household Safety Checklist First Aid: Broken Bones Head Injuries Preventing Children's Sports Injuries ...

  14. First Aid: Rashes

    Science.gov (United States)

    ... Story" 5 Things to Know About Zika & Pregnancy First Aid: Rashes KidsHealth > For Parents > First Aid: Rashes Print A A A Text Size Rashes ... For Kids For Parents MORE ON THIS TOPIC First Aid: Skin Infections Poison Ivy Erythema Multiforme Hives (Urticaria) ...

  15. First Aid: Dehydration

    Science.gov (United States)

    ... Story" 5 Things to Know About Zika & Pregnancy First Aid: Dehydration KidsHealth > For Parents > First Aid: Dehydration Print A A A Text Size Dehydration ... MORE ON THIS TOPIC Summer Safety Heat Illness First Aid: Heat Illness Sun Safety Dehydration Diarrhea Vomiting Word! ...

  16. First Aid: Burns

    Science.gov (United States)

    ... Story" 5 Things to Know About Zika & Pregnancy First Aid: Burns KidsHealth > For Parents > First Aid: Burns Print A A A Text Size Scald ... THIS TOPIC Kitchen: Household Safety Checklist Fireworks Safety First Aid: Sunburn Firesetting Fire Safety Burns Household Safety: Preventing ...

  17. First Aid: Choking

    Science.gov (United States)

    ... Story" 5 Things to Know About Zika & Pregnancy First Aid: Choking KidsHealth > For Parents > First Aid: Choking Print A A A Text Size Choking ... usually are taught as part of any basic first-aid course. Reviewed by: Steven Dowshen, MD Date reviewed: ...

  18. First Aid: Animal Bites

    Science.gov (United States)

    ... Story" 5 Things to Know About Zika & Pregnancy First Aid: Animal Bites KidsHealth > For Parents > First Aid: Animal Bites Print A A A Text Size ... For Kids For Parents MORE ON THIS TOPIC First Aid & Safety Center Infections That Pets Carry Dealing With ...

  19. First Aid: Croup

    Science.gov (United States)

    ... Story" 5 Things to Know About Zika & Pregnancy First Aid: Croup KidsHealth > For Parents > First Aid: Croup Print A A A Text Size Croup ... For Kids For Parents MORE ON THIS TOPIC First Aid: Coughing X-Ray Exam: Neck Why Is Hand ...

  20. Designing State Aid Formulas

    Science.gov (United States)

    Zhao, Bo; Bradbury, Katharine

    2009-01-01

    This paper designs a new equalization-aid formula based on fiscal gaps of local communities. When states are in transition to a new local aid formula, the issue of whether and how to hold existing aid harmless poses a challenge. The authors show that some previous studies and the formulas derived from them give differential weights to existing and…

  1. Tuberculosis and AIDS co-morbidity in Brazil: linkage of the tuberculosis and AIDS databases

    Directory of Open Access Journals (Sweden)

    Angelica Espinosa Miranda

    2009-04-01

    Full Text Available This study evaluated differences in AIDS patients with and without tuberculosis (TB in Espírito Santo State, Brazil. Standard regional AIDS (SINAN, SISCEL, SICLOM and SIM and tuberculosis (SINAN databases were used. TB and AIDS databases were linked using Reclink software, version 3, with SPSS software support to identify co-infected cases. Data from July 2000 to June 2006 in Espírito Santo State were linked. The results showed 3,523 adult AIDS cases and 9,958 adult TB cases resulted in 430 co-infected patients, who were compared to 1,290 AIDS patients who never developed TB. Among 430 co-infected patients, TB was diagnosed first in 223 (51.9%, AIDS was first in 44 (10.2%, and AIDS and TB were diagnosed concurrently in 163 (37.9%. Median age did not differ between co-infected cases (36 years (interquartile range [IQR] 29-43 and non-co-infected cases (34 years; IQR 28-42. Pulmonary tuberculosis was diagnosed in 239 (55.6%; 109 (25.3% had extra-pulmonary TB and 82 (19.1% had both presentations. In the final logistic regression model, living in a metropolitan area [Odds Ratio (OR=1.43 (95% Confidence Interval (CI 1.05-1.95], education < 3 years [OR=3.03 (95%CI 1.56-5.88] and CD4 counts < 200/mm³ [OR=1.14 (95%CI 1.09-1.18] were associated with co-infection. This report emphasizes the significance of tuberculosis among AIDS cases in Brazil, and highlights the importance of evaluating secondary data for purposes of improving data quality and developing public health interventions.

  2. Concurrent radiochemotherapy in advanced hypopharyngeal cancer

    Directory of Open Access Journals (Sweden)

    Lukarski Dusko

    2010-05-01

    Full Text Available Abstract Background Concurrent platinum-based radiochemotherapy has been recommended as a standard of care in patients with locally advanced squamous cell head and neck carcinomas. Unfortunately, there is a lack of level one evidence on best treatment approach for advanced hypopharyngeal cancer. This report aims to summarize the results of our study on concurrent radiochemotherapy in patients with advanced hypopharyngeal cancer. Methods A retrospective analysis of 41 patients with stage III-IV hypopharyngeal cancer was performed. All patients were treated with three dimensional conformal radiotherapy and received 70 Gy in 35 fractions (2 Gy per fraction, 5 fractions per week. In dependence of the period when radiotherapy was realized, two different treatment techniques were used. Concurrent chemotherapy consisted of cisplatin 30 mg/m2 given on a weekly basis. Results The median age was 52 years (range 29-70. Stage IV disease was recognized in 73.2% of the patients. Complete response rates at the primary site and at the metastatic neck lymph nodes were 68.3% and 36.6%, respectively. A complete composite response was present in 27 patients (65.9%. Median follow-up was 13 months (range 7-36. Distant metastases as initial failure occurred in 7 patients (46.7%. The 2-year local relapse-free survival and regional relapse-free survival rates were 55.2% and 75.8%, respectively. The 2-year locoregional relapse-free survival rate was 51.3%. The 2-year disease-free survival and overall survival rates were 29.3% and 32.8%, respectively. Confluent mucositis was developed in 46.3% of patients. Leucopenia grade 1 was the most frequent hematological toxicity. The median weight loss at the end of treatment was 12% (range 5-21. The worst grade of late toxicity was most commonly pronounced in the skin and in the subcutaneous tissue. Conclusions Based on unsatisfactory results in our study we suggest that the use of sequential radiochemotherapy or chemotherapy

  3. Why foreign aid fails

    Directory of Open Access Journals (Sweden)

    Prokopijević Miroslav

    2007-01-01

    Full Text Available The main point of this paper is that foreign aid fails because the structure of its incentives resembles that of central planning. Aid is not only ineffective, it is arguably counterproductive. Contrary to business firms that are paid by those they are supposed to serve (customers, aid agencies are paid by tax payers of developed countries and not by those they serve. This inverse structure of incentives breaks the stream of pressure that exists on the commercial market. It also creates larger loopholes in the principle-agent relationship on each point along the chain of aid delivery. Both factors enhance corruption, moral hazard and negative selection. Instead of promoting development, aid extends the life of bad institutions and those in power. Proposals to reform foreign aid – like aid privatization and aid conditionality – do not change the existing structure of the incentives in aid delivery, and their implementation may just slightly improve aid efficacy. Larger improvement is not possible. For that reason, foreign aid will continue to be a waste of resources, probably serving some objectives different to those that are usually mentioned, like recipient’s development poverty reduction and pain relief.

  4. Correlation between Trichomonas vaginalis and Concurrency: An Ecological Study.

    Science.gov (United States)

    Kenyon, Chris R; Hamilton, Deven T

    2016-01-01

    Objective. There is a large variation in the prevalence of Trichomonas vaginalis (TV) between different countries and between racial groups within countries. Sexual partner concurrency may play a role. We investigate the correlation between the prevalence of sexual partner concurrency and TV prevalence. Methods. Spearman's correlation to assess relationship between TV prevalence in women and point prevalence of concurrency in men in (1) 11 countries with comparable data (concurrency data from WHO Survey and TV prevalence data from Global Burden of Disease estimates) and (2) three racial groups in the United States (Add Health Study). Results. The prevalence of TV and concurrency was positively correlated in the international (rho = 0.84, P = 0.001) and USA study (rho = 1.0, P < 0.001). Conclusion. Prospective longitudinal studies that include measures of partner behavior are required to definitively establish the role of concurrency in the spread of TV.

  5. From Sequential to Concurrent: Correctness and Relative Efficiency

    CERN Document Server

    Gramoli, Vincent; Ravi, Srivatsan

    2012-01-01

    It seems to be generally accepted that designing correct and efficient concurrent software is a sophisticated task that can only be held by experts. A crucial challenge then is to convert sequential code produced by a "mainstream" programmer into concurrent one. Various synchronization techniques may be used for this, e.g., locks or transactional memory, but what does it mean for the resulting concurrent implementation to be correct? And which synchronization primitives provide more efficiency at the end? In this paper, we introduce a correctness criterion for a transformation that enables the use of a sequential data structure in a concurrent system. Informally, we require that the resulting concurrent implementation is \\emph{locally sequential}: concurrent threads simply run the given sequential code and let the implementation worry about the potential conflicts. To make sense globally, the implementation should also be \\emph{linearizable} with respect to the \\emph{object type} of the data structure. We the...

  6. Aid and development

    DEFF Research Database (Denmark)

    Tarp, Finn

    2006-01-01

    Foreign aid looms large in the public discourse; and international development assistance remains squarely on most policy agendas concerned with growth, poverty and inequality in Africa and elsewhere in the developing world. The present review takes a retrospective look at how foreign aid has...... evolved since World War II in response to a dramatically changing global political and economic context. I review the aid process and associated trends in the volume and distribution of aid and categorize some of the key goals, principles and institutions of the aid system. The evidence on whether aid has...... been effective in furthering economic growth and development is discussed in some detail. I add perspective and identify some critical unresolved issues. I finally turn to the current development debate and discuss some key concerns, I believe should be kept in mind in formulating any agenda for aid...

  7. Conditional Aid Effectiveness

    DEFF Research Database (Denmark)

    Doucouliagos, Hristos; Paldam, Martin

    The AEL (aid effectiveness literature) studies the effect of development aid using econometrics on macro data. It contains about 100 papers of which a third analyzes conditional models where aid effectiveness depends upon z, so that aid only works for a certain range of the variable. The key term...... in this family of AEL models is thus an interaction term of z times aid. The leading candidates for z are a good policy index and aid itself. In this paper, meta-analysis techniques are used (i) to determine whether the AEL has established the said interaction terms, and (ii) to identify some of the determinants...... of the differences in results between studies. Taking all available studies in consideration, we find no support for conditionality with respect to policy, while conditionality regarding aid itself is dubious. However, the results differ depending on the authors’ institutional affiliation....

  8. China vs. AIDS

    Institute of Scientific and Technical Information of China (English)

    LURUCAI

    2004-01-01

    CHINA's first HIV positive diagnosis was in 1985, the victim an ArgentineAmerican. At that time most Chinese,medical workers included, thought of AIDS as a phenomenon occurring outside of China. Twenty years later, the number of HIV/AIDS patients has risen alarmingly. In 2003, the Chinese Ministry of Health launched an AIDS Epidemiological Investigation across China with the support of the WHO and UN AIDS Program. Its results show that there are currently 840,000 HIV carriers, including 80,000 people with full-blown AIDS, in 31 Chinese provinces, municipalities and autonomous regions. This means China has the second highest number of HIV/AIDS cases in Asia and 14th highest in the world. Statistics from the Chinese Venereal Disease and AIDS Prevention Association indicate that the majority of Chinese HIV carriers are young to middle aged, more than half of them between the ages of 20 and 29.

  9. Aid and Development

    DEFF Research Database (Denmark)

    Tarp, Finn; Arndt, Channing; Jones, Edward Samuel

    This paper considers the relationship between external aid and development in Mozambique from 1980 to 2004. The main objective is to identify the specific mechanisms through which aid has influenced the developmental trajectory of the country and whether one can plausibly link outcomes to aid...... inputs. We take as our point of departure a growth accounting analysis and review both intended and unintended effects of aid. Mozambique has benefited from sustained aid inflows in conflict, post-conflict and reconstruction periods. In each of these phases aid has made an unambiguous, positive...... contribution both enabling and supporting rapid growth since 1992. At the same time, the proliferation of donors and aid-supported interventions has burdened local administration and there is a distinct need to develop government accountability to its own citizens rather than donor agencies. In ensuring...

  10. Reducing Context-Bounded Concurrent Reachability to Sequential Reachability

    OpenAIRE

    Torre, Salvatore La; Madhusudan, P.; Parlato, Gennaro

    2009-01-01

    We give a translation from concurrent programs to sequential programs that reduces the context-bounded reachability problem in the concurrent program to a reachability problem in the sequential one. The translation has two salient features: (a) the sequential program tracks, at any time, the local state of only one thread (though it does track multiple copies of shared variables), and (b) all reachable states of the sequential program correspond to reachable states of the concurrent program. ...

  11. Comparison of concurrency frameworks for the Java virtual machine

    OpenAIRE

    Kühner, Thomas

    2015-01-01

    Due to Multi-core CPUs, concurrent programming is increasingly important when developing responsive and scalable applications. The programming language Java provides low-level building blocks such as threads and monitors. Multiple frameworks provide higher abstractions for concurrent programming and enable alternative concurrency paradigms on the Java virtual machine. This thesis provides a survey of such frameworks and their appropriate use cases. The thesis introduces the most relevant fram...

  12. Concurrent programming notations in the object-oriented language Arche

    OpenAIRE

    Benveniste, Marc; Issarny, Valérie

    1992-01-01

    Paradigms of object-oriented programming are attractive for the design of large distributed software. They notably provide a sound basis to develop applications that are easy to maintain and reuse. However, expressing concurrency in object-oriented languages raises some difficulties. For instance, integrating concurrency together with inheritance may lead to violate the encapsulation property of object-oriented programming. In this paper we present a new strongly-typed, concurrent object-orie...

  13. Proceedings 8th Interaction and Concurrency Experience

    DEFF Research Database (Denmark)

    2015-01-01

    . During the review phase, each submitted paper is published on a discussion forum with access restricted to the authors and to all the PC members not declaring a conflict of interest. The PC members post comments and questions to which the authors reply. Each paper was reviewed by three PC members, and......This volume contains the proceedings of ICE 2015, the 8th Interaction and Concurrency Experience, which was held in Grenoble, France on the 4th and 5th of June 2015 as a satellite event of DisCoTec 2015. The ICE procedure for paper selection allows PC members to interact, anonymously, with authors...... altogether 9 papers, including 1 short paper, were accepted for publication (the workshop also featured 4 brief announcements which are not part of this volume). We were proud to host three invited talks, by Leslie Lamport (shared with the FRIDA workshop), Joseph Sifakis and Steve Ross-Talbot. The abstracts...

  14. Certifying Concurrent Programs Using Transactional Memory

    Institute of Scientific and Technical Information of China (English)

    Long Li; Yu Zhang; Yi-Yun Chen; Yong Li

    2009-01-01

    Transactional memory (TM) is a new promising concurrency-control mechanism that can avoid many of the pitfalls of the traditional lock-based techniques. TM systems handle data races between threads automatically so that programmers do not have to reason about the interaction of threads manually. TM provides a programming model that may make the development of multi-threaded programs easier. Much work has been done to explore the various implementation strategies of TM systems and to achieve better performance, but little has been done on how to formally reason about programs using TM and how to make sure that such reasoning is sound. In this paper, we focus on the semantics of transactional memory and present a proof-carrying code (PCC) system for reasoning about programs using TM . We formalize our reasoning with respect to the TM semantics, prove its soundness, and use examples to demonstrate its effectiveness.

  15. Distributed Management of Concurrent Web Service Transactions

    DEFF Research Database (Denmark)

    Alrifai, Mohammad; Dolog, Peter; Balke, Wolf-Tilo;

    2009-01-01

    Business processes involve dynamic compositions of interleaved tasks. Therefore, ensuring reliable transactional processing of Web services is crucial for the success of Web service-based B2B and B2C applications. But the inherent autonomy and heterogeneity of Web services render the applicability...... of conventional ACID transaction models for Web services far from being straightforward. Current Web service transaction models relax the isolation property and rely on compensation mechanisms to ensure atomicity of business transactions in the presence of service failures. However, ensuring consistency...... in the open and dynamic environment of Web services, where interleaving business transactions enter and exit the system independently, remains an open issue. In this paper, we address this problem and propose an architecture that supports concurrency control on the Web services level. An extension...

  16. Micro-transactions for concurrent data structures

    DEFF Research Database (Denmark)

    Meawad, Fadi; Iyer, Karthik; Schoeberl, Martin;

    2013-01-01

    Transactional memory is a promising technique for enforcing disciplined access to shared data in a multiprocessor system. Transactional memory simplifies the implementation of a variety of concurrent data structures. In this paper, we study the benefits of a modest, real-time aware, hardware...... implementation of transactional memory that we call micro-transactions. In particular, we argue that hardware support for micro-transactions allows us to efficiently implement certain data structures. Those data structures are difficult to realize with the atomic operations provided by stock hardware and provide...... real-time guarantees for those operations. Our main implementation platform is the Java Optimized Processor system, a field-programmable gate array (FPGA) implementation of the Java virtual machine, optimized for real-time Java. We report on the performance of data structures implemented with locks...

  17. Concurrence et protection sociale en Europe

    OpenAIRE

    Barreau, Catherine-Thérèse; Bellanger, Martine M.; Del Sol, Marion; Frinault, Thomas; Friot, Bernard; Gadbin, Daniel; Hassenteufel, Patrick; Hennion-Moreau, Sylvie; Kaufmann, Otto; Kessler, Francis; Lechevalier, Arnaud; Lhernould, Jean-Philippe; Math, Antoine,; Pierru, Frédéric; Tanguy, Steven

    2015-01-01

    Concilier la libre concurrence et la protection sociale est aujourd'hui l'un des enjeux clefs de l'intégration européenne. La réalisation d'un grand marché européen signifie-t-elle le démantèlement des systèmes de protection sociale existants ? La convergence européenne en matière de politiques sociales et sanitaires ne peut-elle prendre que la voie de la libéralisation ? Cet ouvrage apporte des réponses à ces questions fondamentales pour l'avenir des États providence européens.

  18. Mining Concurrent Topical Activity in Microblog Streams

    CERN Document Server

    Panisson, A; Quaggiotto, M; Cattuto, C

    2014-01-01

    Streams of user-generated content in social media exhibit patterns of collective attention across diverse topics, with temporal structures determined both by exogenous factors and endogenous factors. Teasing apart different topics and resolving their individual, concurrent, activity timelines is a key challenge in extracting knowledge from microblog streams. Facing this challenge requires the use of methods that expose latent signals by using term correlations across posts and over time. Here we focus on content posted to Twitter during the London 2012 Olympics, for which a detailed schedule of events is independently available and can be used for reference. We mine the temporal structure of topical activity by using two methods based on non-negative matrix factorization. We show that for events in the Olympics schedule that can be semantically matched to Twitter topics, the extracted Twitter activity timeline closely matches the known timeline from the schedule. Our results show that, given appropriate techn...

  19. Concurrence vectors for entanglement of high dimensional systems

    Institute of Scientific and Technical Information of China (English)

    You-quan LI; Guo-qiang ZHU

    2008-01-01

    The concurrence vectors are proposed by employing the fundamental representation of An Lie algebra,which provides a clear criterion to evaluate the entanglement of bipartite systems of arbitrary dimension.Accordingly,a state is separable if the norm of its concurrence vector vanishes.The state vectors related to SU(3)states and SO(3) states are discussed in detail.The sign situation of nonzero components of concurrence vectors of entangled bases presents a simple criterion to judge whether the whole Hilbert subspace spanned by those bases is entangled,or there exists an entanglement edge.This is illustrated in terms of the concurrence surfaces of several concrete examples.

  20. A Highly Concurrent Replicated Data Structure EAI Endorsed Transactions

    Directory of Open Access Journals (Sweden)

    Mumtaz Ahmad

    2015-12-01

    Full Text Available Well defined concurrent replicated data structure is very important to design collaborative editing system, particularly, certain properties like out-of-order execution of concurrent operations and data convergence. In this paper, we introduce novel linear data structure based on unique identifier scheme required for indexed communication. These identifiers are real numbers holding specific pattern of precision. Based on the uniqueness and the total order of these identifiers, here, we present two concurrency control techniques to achieve high degree of concurrency according to strong and lazy happened-before relations. Our data structure preserves data convergence, yields better performance and avoids overheads as compared to existing approaches.

  1. An Efficient Secure Real-Time Concurrency Control Protocol

    Institute of Scientific and Technical Information of China (English)

    XIAO Yingyuan; LIU Yunsheng; CHEN Xiangyang

    2006-01-01

    Secure real-time databases must simultaneously satisfy two requirements in guaranteeing data security and minimizing the missing deadlines ratio of transactions. However, these two requirements can conflict with each other and achieve one requirement is to sacrifice the other. This paper presents a secure real-time concurrency control protocol based on optimistic method. The concurrency control protocol incorporates security constraints in a real-time optimistic concurrency control protocol and makes a suitable tradeoff between security and real-time requirements by introducing secure influence factor and real-time influence factor. The experimental results show the concurrency control protocol achieves data security without degrading real-time performance significantly.

  2. Computer Program Re-layers Engineering Drawings

    Science.gov (United States)

    Crosby, Dewey C., III

    1990-01-01

    RULCHK computer program aids in structuring layers of information pertaining to part or assembly designed with software described in article "Software for Drawing Design Details Concurrently" (MFS-28444). Checks and optionally updates structure of layers for part. Enables designer to construct model and annotate its documentation without burden of manually layering part to conform to standards at design time.

  3. Computer graphics in engineering education

    CERN Document Server

    Rogers, David F

    2013-01-01

    Computer Graphics in Engineering Education discusses the use of Computer Aided Design (CAD) and Computer Aided Manufacturing (CAM) as an instructional material in engineering education. Each of the nine chapters of this book covers topics and cites examples that are relevant to the relationship of CAD-CAM with engineering education. The first chapter discusses the use of computer graphics in the U.S. Naval Academy, while Chapter 2 covers key issues in instructional computer graphics. This book then discusses low-cost computer graphics in engineering education. Chapter 4 discusses the uniform b

  4. Aid and Growth

    DEFF Research Database (Denmark)

    Arndt, Channing; Jones, Edward Samuel; Tarp, Finn

    The micro-macro paradox has been revived. Despite broadly positive evaluations at the micro and meso-levels, recent literature has turned decidedly pessimistic with respect to the ability of foreign aid to foster economic growth. Policy implications, such as the complete cessation of aid to Africa......, are being drawn on the basis of fragile evidence. This paper first assesses the aid-growth literature with a focus on recent contributions. The aid-growth literature is then framed, for the first time, in terms of the Rubin Causal Model, applied at the macroeconomic level. Our results show that aid has...... a positive and statistically significant causal effect on growth over the long run with point estimates at levels suggested by growth theory. We conclude that aid remains an important tool for enhancing the development prospects of poor nations....

  5. Aid Effectiveness on Growth

    DEFF Research Database (Denmark)

    Doucouliagos, Hristos; Paldam, Martin

    The AEL (aid effectiveness literature) is econo¬metric studies of the macroeconomic effects of development aid. It contains about 100 papers of which 68 are reduced form estimates of theeffect of aid on growth in the recipient country. The raw data show that growth is unconnected to aid......, but the AEL has put so much structure on the data that all results possible have emerged. The present meta study considers both the best-set of the 68 papers and the all-set of 543 regressions published. Both sets have a positive average aid-growth elasticity, but it is small and insignificant: The AEL has...... not established that aid works. Using meta-regression analysis it is shown that about 20 factors influence the results. Much of the variation between studies is an artifact and can be attributed to publication outlet, institu¬tional affiliation, and specification differences. However, some of the difference...

  6. Radiographic imaging of aids

    CERN Document Server

    Mahmoud, M B

    2002-01-01

    The acquired immunodeficiency syndrome (AIDS) has impacted the civilized world like no other disease. This research aimed to discuss some of the main aids-related complications and their detection by radiology tests, specifically central nervous system and musculoskeletal system disorders. The objectives are: to show specific characteristics of various diseases of HIV patient, to analyze the effect of pathology in patients by radiology, to enhance the knowledge of technologists in aids imaging and to improve communication skills between patient and radiology technologists.

  7. Hearing Aids and Music

    OpenAIRE

    Chasin, Marshall; Russo, Frank A.

    2004-01-01

    Historically, the primary concern for hearing aid design and fitting is optimization for speech inputs. However, increasingly other types of inputs are being investigated and this is certainly the case for music. Whether the hearing aid wearer is a musician or merely someone who likes to listen to music, the electronic and electro-acoustic parameters described can be optimized for music as well as for speech. That is, a hearing aid optimally set for music can be optimally set for speech, even...

  8. AIDS: acquired immunodeficiency syndrome

    OpenAIRE

    Gilmore, N. J.; Beaulieu, R.; Steben, M.; Laverdière, M.

    2002-01-01

    Acquired immunodeficiency syndrome, or AIDS, is a new illness that occurs in previously healthy individuals. It is characterized by immunodeficiency, opportunistic infections and unusual malignant diseases. Life-threatening single or multiple infections with viruses, mycobacteria, fungi or protozoa are common. A rare neoplasm, Kaposi's sarcoma, has developed in approximately one third of patients with AIDS. More than 800 cases of AIDS have been reported in North America, over 24 of them in Ca...

  9. Aid, growth, and development

    DEFF Research Database (Denmark)

    Arndt, Channing; Jones, Edward Samuel; Tarp, Finn

    2010-01-01

    The micro-macro paradox has been revived. Despite broadly positive evaluations at the micro- and meso-levels, recent literature doubts the ability of foreign aid to foster economic growth and development. This paper assesses the aid-growth literature and, taking inspiration from the program...... evaluation literature, we re-examine key hypotheses. In our findings, aid has a positive and statistically significant causal effect on growth over the long run, with confidence intervals conforming to levels suggested by growth theory. Aid remains a key tool for enhancing the development prospects of poor...

  10. Music and hearing aids.

    Science.gov (United States)

    Madsen, Sara M K; Moore, Brian C J

    2014-01-01

    The signal processing and fitting methods used for hearing aids have mainly been designed to optimize the intelligibility of speech. Little attention has been paid to the effectiveness of hearing aids for listening to music. Perhaps as a consequence, many hearing-aid users complain that they are not satisfied with their hearing aids when listening to music. This issue inspired the Internet-based survey presented here. The survey was designed to identify the nature and prevalence of problems associated with listening to live and reproduced music with hearing aids. Responses from 523 hearing-aid users to 21 multiple-choice questions are presented and analyzed, and the relationships between responses to questions regarding music and questions concerned with information about the respondents, their hearing aids, and their hearing loss are described. Large proportions of the respondents reported that they found their hearing aids to be helpful for listening to both live and reproduced music, although less so for the former. The survey also identified problems such as distortion, acoustic feedback, insufficient or excessive gain, unbalanced frequency response, and reduced tone quality. The results indicate that the enjoyment of listening to music with hearing aids could be improved by an increase of the input and output dynamic range, extension of the low-frequency response, and improvement of feedback cancellation and automatic gain control systems. PMID:25361601

  11. Music and Hearing Aids

    Directory of Open Access Journals (Sweden)

    Sara M. K. Madsen

    2014-10-01

    Full Text Available The signal processing and fitting methods used for hearing aids have mainly been designed to optimize the intelligibility of speech. Little attention has been paid to the effectiveness of hearing aids for listening to music. Perhaps as a consequence, many hearing-aid users complain that they are not satisfied with their hearing aids when listening to music. This issue inspired the Internet-based survey presented here. The survey was designed to identify the nature and prevalence of problems associated with listening to live and reproduced music with hearing aids. Responses from 523 hearing-aid users to 21 multiple-choice questions are presented and analyzed, and the relationships between responses to questions regarding music and questions concerned with information about the respondents, their hearing aids, and their hearing loss are described. Large proportions of the respondents reported that they found their hearing aids to be helpful for listening to both live and reproduced music, although less so for the former. The survey also identified problems such as distortion, acoustic feedback, insufficient or excessive gain, unbalanced frequency response, and reduced tone quality. The results indicate that the enjoyment of listening to music with hearing aids could be improved by an increase of the input and output dynamic range, extension of the low-frequency response, and improvement of feedback cancellation and automatic gain control systems.

  12. HIV / AIDS Network.

    Science.gov (United States)

    1995-01-01

    The HIV/AIDS Network and the Philippines Department of Health (DOH) collaborated to produce the AIDS Candlelight Memorial at the Philippine International Convention Center (PICC), May 1995, and World AIDS Day activities on December 1, 1995. After the memorial, a fashion show, "Body Shots," provided a channel for information on acquired immunodeficiency syndrome (AIDS). On World AIDS Day, at the request of DOH, the Network provided speakers who lectured on human immunodeficiency virus (HIV) and AIDS in different government offices. Prior to World AIDS Day, the Network focused on strengthening its cohesiveness and building the capabilities of its member organizations through lectures and symposia during November. Network activities were coordinated by the Remedios AIDS Foundation with support from the other members of the Coordinating Council: Health Action Information Network (HAIN); Caritas; Kabalikat, Stop Trafficking of Pilopinos Foundation, Inc. (STOP);and the Library Foundation (TLF). The Coordinating Council elected for 1996 includes the Remedios AIDS Foundation, HAIN, Caritas, TLF, STOP, the Foundation for Adolescent Development (FAD), and the Salvation Army. PMID:12291699

  13. Music and hearing aids.

    Science.gov (United States)

    Madsen, Sara M K; Moore, Brian C J

    2014-10-31

    The signal processing and fitting methods used for hearing aids have mainly been designed to optimize the intelligibility of speech. Little attention has been paid to the effectiveness of hearing aids for listening to music. Perhaps as a consequence, many hearing-aid users complain that they are not satisfied with their hearing aids when listening to music. This issue inspired the Internet-based survey presented here. The survey was designed to identify the nature and prevalence of problems associated with listening to live and reproduced music with hearing aids. Responses from 523 hearing-aid users to 21 multiple-choice questions are presented and analyzed, and the relationships between responses to questions regarding music and questions concerned with information about the respondents, their hearing aids, and their hearing loss are described. Large proportions of the respondents reported that they found their hearing aids to be helpful for listening to both live and reproduced music, although less so for the former. The survey also identified problems such as distortion, acoustic feedback, insufficient or excessive gain, unbalanced frequency response, and reduced tone quality. The results indicate that the enjoyment of listening to music with hearing aids could be improved by an increase of the input and output dynamic range, extension of the low-frequency response, and improvement of feedback cancellation and automatic gain control systems.

  14. Concurrent Chemoradiotherapy in Locally Advanced Esophageal Cancer

    International Nuclear Information System (INIS)

    This study was designed to evaluate the results of local control, survival rate, prognostic factors, and failure pattern in locally advanced esophageal cancer. We retrospectively studied 50 patients with locally advanced esophageal cancer treated with concurrent chemoradiotherapy at Keimyung University Dongsan Medical Center from June of 1999 to August of 2008. Seven patients with inappropriate data were excluded, and 43 patients were analyzed. There were 39 males and four female patients ranging in age from 43 to 78 years (median, 63 years). There were seven patients with stage IIA and 36 with stage III. Irradiation from 46 Gy to 63 Gy (median, 54 Gy) was carried out 5 days per week, 1.8 Gy once a day. There were eight patients with neo-adjuvant chemotherapy, and we mostly used 5-fluorouracil, cisplatin with 3 cycles for concurrent chemotherapy. The range of follow up periods was from 2 to 82 months (median, 15.5). There were nine patients that exhibited a complete response, 23 that exhibited a partial response, 9 that exhibited no response, and 2 that exhibited disease progression. The median survival time was 15 months. Two-year and 5-year survival rates were 36.5% and 17.3%, respectively. Two-year and 5-year disease-free survival rates were 32.4% and 16%, respectively. Treatment failure occurred in 22 patients (51.2%). Patterns of failure were categorized as local failure in 18 patients and distant metastasis in four patients. In a univariate analysis for prognostic factors related to overall survival and disease-free survival, the hemoglobin levels during chemoradiotherapy (≥12 vs. <12, p=0.02/p=0.1) and the response to the treatments (CR/PR vs. NR/PD, p=0.002/p <0.0001) were statistically significant. In a multivariate analysis, only response to the treatments was revealed to be statistically significant. There was no statistical significance associated with patient age, gender, disease stage, T-stage, smoking history, tumor location, or neo

  15. Concurrent malaria and dengue infection: a brief summary and comment

    OpenAIRE

    Wiwanitkit, Viroj

    2011-01-01

    There are several tropical mosquito borne infections. Malaria and dengue are the two common mosquito infections that are very important and cause high morbidity and mortality for many patients around the world. Concurrent malaria and dengue infection is an important condition that is seldom reported. In this specific article, the author hereby summarizes on the topic of concurrent malaria and dengue infection.

  16. Reasoning about Concurrent Actionsin Multi-Agent Systems

    Institute of Scientific and Technical Information of China (English)

    FAN Xiaocong; XU Dianxiang; HOU Jianmin; ZHENG Guoliang

    1999-01-01

    Concurrence is an important researcharea in collaborative problem solving.This paper offers a formaldefinition for cooperative sequences in multi-agentsystems, discussesthe different categories of concurrent actions, and proposes somerules forsituation revision and an algorithm used to generate resultingsituations.An example is also given to show how to solve concurrentproblems occurring inmulti-agent systems.

  17. 39 CFR 273.7 - Concurrence of Attorney General.

    Science.gov (United States)

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Concurrence of Attorney General. 273.7 Section 273... PROGRAM FRAUD CIVIL REMEDIES ACT § 273.7 Concurrence of Attorney General. (a) The Attorney General is... the Attorney General or his designee approves such action in a written statement which specifies:...

  18. Concurrent Lexicalized Dependency Parsing The ParseTalk Model

    CERN Document Server

    Broeker, N; Schacht, S; Broeker, Norbert; Hahn, Udo; Schacht, Susanne

    1994-01-01

    A grammar model for concurrent, object-oriented natural language parsing is introduced. Complete lexical distribution of grammatical knowledge is achieved building upon the head-oriented notions of valency and dependency, while inheritance mechanisms are used to capture lexical generalizations. The underlying concurrent computation model relies upon the actor paradigm. We consider message passing protocols for establishing dependency relations and ambiguity handling.

  19. CAME-Computer Aided Maintenance Engineering: a new methodology to reduce maintenance life cycle cost pipelines (repair level, spares, preventive/scheduled/inspection and resources) by modeling, analysis and optimization

    Energy Technology Data Exchange (ETDEWEB)

    Bot, Yizhak [BQR Reliability Engineering Ltd. (Israel)

    2005-07-01

    In today's insecure and uncertain climate in the high-tech industry, where money is less accessible, companies are constantly searching for ways to cut expenses. Two important financial factors to consider are maintenance and down time when the equipment/system/processes are not functioning/operating. In this paper we shall describe a new technology, which will help designers and operators of complex systems to improve the reliability of the products and to reduce the maintenance cost, when they are used in field. These set of tools are interfaced to exist CAD/CAE and ERP/CMMS systems concurrently. (author)

  20. Rotational and Helical Surface Approximation for Reverse Engineering

    DEFF Research Database (Denmark)

    Randrup, Thomas; Pottmann, Helmut

    1997-01-01

    to basic shapes used in computer aided design. The algorithms apply methods of line geometry to the set of surface normals in combination with techniques of numerical approximation. The presented results possess applications in reverse engineering and computer aided manufacturing....

  1. Viscothermal acoustics using finite elements : analysis tools for engineers

    NARCIS (Netherlands)

    Kampinga, Wim Ronald

    2010-01-01

    Hearing aids contain miniature loudspeakers and microphones. Following the trend of miniaturization, hearing aids and the acoustic transducers inside become smaller and smaller. This presents new challenges for engineers who develop such transducers. Because of the small geometries, the viscothermal

  2. Concurrent Object-Oriented Programming Based on MPI

    Institute of Scientific and Technical Information of China (English)

    鲁宏伟; 汪厚祥; 裴晓黎; 肖永玲

    2004-01-01

    Object-oriented model possesses inherent concurrency. Integration of concurrency and object-orientation is a promising new field. MPI is a message-passing standard and has been adopted by more and more systems. This paper proposes a novel approach to realize concurrent object-oriented programming based on Message-passing interface(MPI) in which future method communication is adopted between concurrent objects. A state behavior set is proposed to solve inheritance anomaly, and a bounded buffer is taken as an example to illustrate this proposal. The definition of ParaMPI class, which is the most important class in the concurrent class library,and implementation issues are briefly described.

  3. Proceedings Fourth Interaction and Concurrency Experience

    CERN Document Server

    Silva, Alexandra; Bruni, Roberto; Carbone, Marco; 10.4204/EPTCS.59

    2011-01-01

    This volume contains the pre-proceedings of ICE'11, the 4th Interaction and Concurrency Experience workshop, which was held in Reykjavik, Iceland on the 9th of June 2011 as a satellite event of DisCoTec'11. The topic of ICE'11 was Reliable and Contract-based Interaction. Reliable interactions are, e.g., those enjoying suitable logical, behavioural, or security properties, or adhering to certain QoS standards. Contract-based interactions are, e.g., those where the interacting entities are committed to give certain guarantees whenever certain assumptions are met by their operating environment. The ICE procedure for paper selection allows for PC members to interact, anonymously, with authors. During the review phase, each submitted paper is published on a Wiki and associated with a discussion forum whose access is restricted to the authors and to all the PC members not declaring a conflict of interests. The PC members post comments and questions that the authors reply to. Each paper was reviewed by four PC membe...

  4. Concurrency Control Technique in RFID Implementation

    Directory of Open Access Journals (Sweden)

    Ajaegbu C

    2014-03-01

    Full Text Available Database techniques have been used to proffer solution to some challenging situations that has to do with management of data in industries. This idea can also be valuable and implemented in managing the operation mode of some devices during t he design level stage. The proposition of Radio Frequency Identification Detection technology as a convenient and automatic instrument of identification and detection has shown value in usage in the society. However, it has been identified with some challenges such as collision despite its prospects. The need to mitigate collision between a reader and multiple tags is of importance for effective deployment of the technology. The paper aimed at integrating one of the concepts of database management technique of concurrency control known as Time-Stamp (TS in order to offer solution to the problem of collision in RFID implementation. This paper adopted a small scale business scenario which was used to illustrate the benefit this stands to offer in the real-life implementation. The paper concluded by arguing that this technique can be adopted and implemented and by such doing, will enhance further the performance of RFID technology.

  5. CONCURRENCY CONTROL TECHNIQUE IN RFID IMPLEMENTATION

    Directory of Open Access Journals (Sweden)

    Ajaegbu C

    2015-11-01

    Full Text Available Database techniques have been used to proffer solution to some challenging situations that has to do with management of data in industries. This idea can also be valuable and implemented in managing the operation mode of some devices during the design level stage. The proposition of Radio Frequency Identification Detection technology as a convenient and automatic instrument of identification and detection has shown value in usage in the society. However, it has been identified with some challenges such as collision despite its prospects. The need to mitigate collision between a reader and multiple tags is of importance for effective deployment of the technology. The paper aimed at integrating one of the concepts of database management technique of concurrency control known as Time-Stamp (TS in order to offer solution to the problem of collision in RFID implementation. This paper adopted a small scale business scenario which was used to illustrate the benefit this stands to offer in the real-life implementation. The paper concluded by arguing that this technique can be adopted and implemented and by such doing, will enhance further the performance of RFID technology.

  6. Concurrent Oxytocin in Women Needing Second Dinoprostone

    International Nuclear Information System (INIS)

    Objective: To reduce average induction delivery internal in patients with poor Bishop score without compromising fetomaternal outcome (in terms of birth weight, NICU admission, maternal complications and mode of delivery). Study Design: A descriptive study. Place and Duration of Study: Department of Obstetrics and Gynaecology, Pakistan Atomic Energy Commission (PAEC) General Hospital, Islamabad, from February to December 2009. Methodology: All patients needing 2nd dinoprostone pessary for induction of labour were included in the study. Patients with gestation below 37 weeks, those with intra-uterine growth restriction, bad obstetric history, previous uterine scar and patients in whom Bishop score improved for amniotomy after 1st dinoprostone pessary, were excluded. Data was collected on a special proforma where all variables were defined. Results:Out of 90 patients, 44 (48.8 percentage) had spontaneous vertex deliveries and 12 (13.3 percentage) had instrumental deliveries so a total vaginal deliveries occurred in 56 (62.2 percentage) patients. Thirty four patients (37.8 percentage) had emergency caesarean sections. Main indication for cesarean was failure to progress in 1st stage of labour followed by fetal distress. There were 3 failed inductions. Only 2 patients had hyperstimulation. NICU admission were 8 and all babies were discharged healthy from nursery with no case of early neonatal death. Conclusion:Concurrent oxytocin with 2nd dinoprostone in patients with poor Bishop scores (initial scores 2 and 3) resulted in more vaginal birth and comparatively shorter induction delivery time with almost negligible fetomaternal complications. (author)

  7. AIDS is your business.

    Science.gov (United States)

    Rosen, Sydney; Simon, Jonathon; Vincent, Jeffrey R; MacLeod, William; Fox, Matthew; Thea, Donald M

    2003-02-01

    If your company operates in a developing country, AIDS is your business. While Africa has received the most attention, AIDS is also spreading swiftly in other parts of the world. Russia and Ukraine had the fastest-growing epidemics last year, and many experts believe China and India will suffer the next tidal wave of infection. Why should executives be concerned about AIDS? Because it is destroying the twin rationales of globalization strategy-cheap labor and fast-growing markets--in countries where people are heavily affected by the epidemic. Fortunately, investments in programs that prevent infection and provide treatment for employees who have HIV/AIDS are profitable for many businesses--that is, they lead to savings that outweigh the programs' costs. Due to the long latency period between HIV infection and the onset of AIDS symptoms, a company is not likely to see any of the costs of HIV/AIDS until five to ten years after an employee is infected. But executives can calculate the present value of epidemic-related costs by using the discount rate to weigh each cost according to its expected timing. That allows companies to think about expenses on HIV/AIDS prevention and treatment programs as investments rather than merely as costs. The authors found that the annual cost of AIDS to six corporations in South Africa and Botswana ranged from 0.4% to 5.9% of the wage bill. All six companies would have earned positive returns on their investments if they had provided employees with free treatment for HIV/AIDS in the form of highly active antiretroviral therapy (HAART), according to the mathematical model the authors used. The annual reduction in the AIDS "tax" would have been as much as 40.4%. The authors' conclusion? Fighting AIDS not only helps those infected; it also makes good business sense. PMID:12577655

  8. The new six-cylinder motorcycle engine from BMW

    Energy Technology Data Exchange (ETDEWEB)

    Mattes, Wolfgang; Hege, Heinz; Haimerl, Michael; Unterweger, Georg [BMW Motorrad, Muenchen (Germany)

    2011-06-15

    For the first time ever BMW uses a six-cylinder engine for a motorcycle. For the new K1600GT and K1600GTL BMW Motorrad has developed a six-cylinder inline engine, which exceeds a four-cylinder especially under the aspect of engine smoothness and concurrently acts on the same level of fuel consumption. (orig.)

  9. The Power of STEP for the Exchange of Engineering Information between CA(X) Systems

    DEFF Research Database (Denmark)

    Sørensen, Torben; Conrad, Finn

    1999-01-01

    resources into physical files and databases in formats that comply with the standard, even though the information contents is not defined in any standard resource model. The only demand is that the information model resources used by the receiving CA(X) system must be identical to those applied...... resources and methodologies, and the paper further addresses how to use STEP for IPD of hydraulic components and systems based upon the concurrent engineering of different computer aided CA(X) systems.International standardization based on ISO10303, STEP, is playing a key role in promoting a modern approach...... of being broadly realized.These twelve initial STEP parts primarily comprehend complete information model resources for CAD geometry and kinematics descriptions, as well as methodologies for information modeling and information mapping into database models and physical files, etc.For IPD of hydraulic...

  10. Persons with Alzheimer's Disease Make Phone Calls Independently Using a Computer-Aided Telephone System

    Science.gov (United States)

    Perilli, Viviana; Lancioni, Giulio E.; Singh, Nirbhay N.; O'Reilly, Mark F.; Sigafoos, Jeff; Cassano, Germana; Cordiano, Noemi; Pinto, Katia; Minervini, Mauro G.; Oliva, Doretta

    2012-01-01

    This study assessed whether four patients with a diagnosis of Alzheimer's disease could make independent phone calls via a computer-aided telephone system. The study was carried out according to a non-concurrent multiple baseline design across participants. All participants started with baseline during which the telephone system was not available,…

  11. AIDS Epidemiological models

    Science.gov (United States)

    Rahmani, Fouad Lazhar

    2010-11-01

    The aim of this paper is to present mathematical modelling of the spread of infection in the context of the transmission of the human immunodeficiency virus (HIV) and the acquired immune deficiency syndrome (AIDS). These models are based in part on the models suggested in the field of th AIDS mathematical modelling as reported by ISHAM [6].

  12. AIDS as Metaphor.

    Science.gov (United States)

    McMillen, Liz

    1994-01-01

    Scholarly interest in Acquired Immune Deficiency Syndrome (AIDS) has spread throughout the humanities, attracting the attention of historians of medicine, political scientists, sociologists, public health scholars, and anthropologists. Most theorists hope their research will aid in policymaking or change understanding of the epidemic. (MSE)

  13. [Oral hygiene aids].

    Science.gov (United States)

    Hovius, M; Leemans, G J

    1994-05-01

    Different dental hygiene aids are discussed, such as floss, tape, superfloss, gauze, flat shoelace, toothpick, interproximal brush, single-tufted brush, electric toothbrush, manual toothbrush and oral irrigation. Research shows that not one specific aid is superior to another if effectiveness is taken into consideration. Other factors which can influence oral hygiene efficacy are discussed as well. PMID:11830968

  14. AIDS and Chemical Dependency.

    Science.gov (United States)

    Pohl, Melvin I.

    After defining HIV and the AIDS disease and outlining symptoms and means of infection, this fact sheet lists the ways alcohol and drugs are involved with the AIDS epidemic, noting that needle-sharing transmits the virus; that alcohol or mood-altering drugs like crack cocaine cause disinhibition, increase sex drive, encourage sex for drugs, and…

  15. Changing epidemiology of AIDS.

    OpenAIRE

    Donovan, C. A.; Stratton, E.

    1994-01-01

    It has been 15 years since AIDS made its first appearance in North America, probably longer worldwide. In that time, our knowledge of the epidemiology of AIDS has grown and changed. This review highlights significant aspects of the epidemic with particular emphasis on the evolution of this disease in North America.

  16. The Aid Effectiveness Literature

    DEFF Research Database (Denmark)

    Doucouliagos, Hristos; Paldam, Martin

    The AEL consists of empirical macro studies of the effects of development aid. At the end of 2004 it had reached 97 studies of three families, which we have summarized in one study each using meta-analysis. Studies of the effect on investments show that they rise by 1/3 of the aid – the rest is c...

  17. Aid and Income

    DEFF Research Database (Denmark)

    Lof, Matthijs; Mekasha, Tseday Jemaneh; Tarp, Finn

    2015-01-01

    to nonrandom omission of a large proportion of observations. Furthermore, we show that NDHKM’s use of co-integrated regressions is not a suitable empirical strategy for estimating the causal effect of aid on income. Evidence from a Panel VAR model estimated on the dataset of NDHKM, suggests a positive...... and statistically significant long-run effect of aid on income....

  18. International Aid to Education

    Science.gov (United States)

    Benavot, Aaron

    2010-01-01

    Recent evidence highlights several worrisome trends regarding aid pledges and disbursements, which have been exacerbated by the global financial crisis. First, while overall development assistance rose in 2008, after 2 years of decline, the share of all sector aid going to the education sector has remained virtually unchanged at about 12 percent…

  19. Genetic Immunity to AIDS

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In an article on genetic immunity to AIDS published in Science magazine, American and Chinese scientists claim to have discovered why certain HIV carriers do not develop full-blown AIDS. They say that the key to this conundrum lies in a particular protein in the endocrine system that inhibits development of HIV.

  20. Hearing aid and Noise

    OpenAIRE

    Ahmad Reza Nazeri

    1999-01-01

    Prescription of hearing aid is an extensive special category of knowledge in the field of audiology. This article is aimed at discussing the function of hearing aid and also management of patients in the noisy environments and presenting solutions to overcome problems regarding to this issue along with taking a look to the equipments prepared nowadays to cope with noisy situations.