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Sample records for dielectrics-an engineering approach

  1. On the electrical breakdown of gaseous dielectrics-an engineering approach

    DEFF Research Database (Denmark)

    Pedersen, Aage

    1989-01-01

    . In addition, the criteria developed do not contain any arbitrary constants. By introducing the electrode surface mean curvature, it is shown that the calculation of breakdown data for widely different electrode shapes can be addressed through a single formula. It is emphasized that the inherent roughness...

  2. On the electrical breakdown of gaseous dielectrics-an engineering approach

    DEFF Research Database (Denmark)

    Pedersen, Aage

    1989-01-01

    Quantitative criteria are derived for the onset of breakdown in atmospheric air and similar weakly electronegative gases. A comparable criterion is then formulated for strongly electronegative gases such as SF6. These criteria contain no quantities other than those which can be obtained directly ...... approximation to the field distribution can render an extensive calculation of the electrostatic field unnecessary. The discussion deals exclusively with situations in which the onset of breakdown in the system is synonymous with the onset of a corona discharge......Quantitative criteria are derived for the onset of breakdown in atmospheric air and similar weakly electronegative gases. A comparable criterion is then formulated for strongly electronegative gases such as SF6. These criteria contain no quantities other than those which can be obtained directly...

  3. Thermodynamics an engineering approach

    CERN Document Server

    Cengel, Yunus A

    2014-01-01

    Thermodynamics, An Engineering Approach, eighth edition, covers the basic principles of thermodynamics while presenting a wealth of real-world engineering examples so students get a feel for how thermodynamics is applied in engineering practice. This text helps students develop an intuitive understanding by emphasizing the physics and physical arguments. Cengel and Boles explore the various facets of thermodynamics through careful explanations of concepts and use of numerous practical examples and figures, having students develop necessary skills to bridge the gap between knowledge and the confidence to properly apply their knowledge. McGraw-Hill is proud to offer Connect with the eighth edition of Cengel/Boles, Thermodynamics, An Engineering Approach. This innovative and powerful new system helps your students learn more efficiently and gives you the ability to assign homework problems simply and easily. Problems are graded automatically, and the results are recorded immediately. Track individual stude...

  4. Engineering Students' Sustainability Approaches

    Science.gov (United States)

    Haase, S.

    2014-01-01

    Sustainability issues are increasingly important in engineering work all over the world. This article explores systematic differences in self-assessed competencies, interests, importance, engagement and practices of newly enrolled engineering students in Denmark in relation to environmental and non-environmental sustainability issues. The…

  5. Engineering Students' Sustainability Approaches

    Science.gov (United States)

    Haase, S.

    2014-01-01

    Sustainability issues are increasingly important in engineering work all over the world. This article explores systematic differences in self-assessed competencies, interests, importance, engagement and practices of newly enrolled engineering students in Denmark in relation to environmental and non-environmental sustainability issues. The…

  6. Nonlinear Approaches in Engineering Applications

    CERN Document Server

    Jazar, Reza

    2012-01-01

    Nonlinear Approaches in Engineering Applications focuses on nonlinear phenomena that are common in the engineering field. The nonlinear approaches described in this book provide a sound theoretical base and practical tools to design and analyze engineering systems with high efficiency and accuracy and with less energy and downtime. Presented here are nonlinear approaches in areas such as dynamic systems, optimal control and approaches in nonlinear dynamics and acoustics. Coverage encompasses a wide range of applications and fields including mathematical modeling and nonlinear behavior as applied to microresonators, nanotechnologies, nonlinear behavior in soil erosion,nonlinear population dynamics, and optimization in reducing vibration and noise as well as vibration in triple-walled carbon nanotubes. This book also: Provides a complete introduction to nonlinear behavior of systems and the advantages of nonlinearity as a tool for solving engineering problems Includes applications and examples drawn from the el...

  7. Interdisciplinary Approach in Engineering Education

    Directory of Open Access Journals (Sweden)

    Anda Zeidmane

    2011-04-01

    Full Text Available The analysis of the scientific literature available on the types of general competences and their classification caused the authors to conclude that it is necessary to implement interdisciplinary approach in engineering education to develop competences necessary for engineers to make them competitive in the labour market. The attention should be paid to a professional foreign language, computer literacy and educational psychology recommendations. To improve professional foreign language skills, CLIL (Content and Language Integrated Learning method should be integrated in the study process of engineering education. In order to develop information literacy competence, it is important to create a single e-study environment. The academic staff, developing study subjects for engineering programmes, should focus on the study content and study methods. As regards the content, the compromise should be sought between fundamental acquisition of the knowledge of the subject matter, the know-how of the application of this knowledge as well as the use of brand new software in the calculations. The paper presents the examples of the application of the interdisciplinary approach in the universities, where the authors of the paper are affiliated: the LUA (Latvia University of Agriculture and the RTU (Riga Technical University, respectively.

  8. A Viable Systems Engineering Approach

    Science.gov (United States)

    2010-04-01

    methodology was not meeting the needs of the sponsors • The Agile approach Scrum was selected as the only viable solution for managing project...Self-organized teams Slide 11 Source: Agile Alliance (http://www.agilealliance.org/) Scrum Applied to Systems Engineering • Scrum is a framework for...ceremonies • A Scrum project is a series of iterations or Sprints where every 2-4 weeks produces fully developed requirements, functional analyses, and

  9. Nonlinear approaches in engineering applications 2

    CERN Document Server

    Jazar, Reza N

    2013-01-01

    Provides updated principles and applications of the nonlinear approaches in solving engineering and physics problems Demonstrates how nonlinear approaches may open avenues to better, safer, cheaper systems with less energy consumption Has a strong emphasis on the application, physical meaning, and methodologies of nonlinear approaches in different engineering and science problems

  10. Rethinking engineering education the CDIO approach

    CERN Document Server

    Crawley, Edward F; Östlund, Sören; Brodeur, Doris R; Edström, Kristina

    2014-01-01

    This book describes an approach to engineering education that integrates a comprehensive set of personal, interpersonal, and professional engineering skills with engineering disciplinary knowledge in order to prepare innovative and entrepreneurial engineers.  The education of engineers is set in the context of engineering practice, that is, Conceiving, Designing, Implementing, and Operating (CDIO) through the entire lifecycle of engineering processes, products, and systems. The book is both a description of the development and implementation of the CDIO model and a guide to engineering programs worldwide that seek to improve the education of young engineers.   Provides an overview of the CDIO approach, then chapters organized according to the CDIO Standards; Includes in each chapter objectives, discussion questions, case studies and clear diagrams to support key concepts and processes; Avoids the jargon of education specialists and clearly explains education terms in the context of their initial presentatio...

  11. Software engineering a practitioner's approach

    CERN Document Server

    Pressman, Roger S

    1997-01-01

    This indispensable guide to software engineering exploration enables practitioners to navigate the ins and outs of this rapidly changing field. Pressman's fully revised and updated Fourth Edition provides in-depth coverage of every important management and technical topic in software engineering. Moreover, readers will find the inclusion of the hottest developments in the field such as: formal methods and cleanroom software engineering, business process reengineering, and software reengineering.

  12. A systematic approach to engineering ethics education.

    Science.gov (United States)

    Li, Jessica; Fu, Shengli

    2012-06-01

    Engineering ethics education is a complex field characterized by dynamic topics and diverse students, which results in significant challenges for engineering ethics educators. The purpose of this paper is to introduce a systematic approach to determine what to teach and how to teach in an ethics curriculum. This is a topic that has not been adequately addressed in the engineering ethics literature. This systematic approach provides a method to: (1) develop a context-specific engineering ethics curriculum using the Delphi technique, a process-driven research method; and (2) identify appropriate delivery strategies and instructional strategies using an instructional design model. This approach considers the context-specific needs of different engineering disciplines in ethics education and leverages the collaboration of engineering professors, practicing engineers, engineering graduate students, ethics scholars, and instructional design experts. The proposed approach is most suitable for a department, a discipline/field or a professional society. The approach helps to enhance learning outcomes and to facilitate ethics education curriculum development as part of the regular engineering curriculum.

  13. Engineering strategic approach as organizational necessary

    Directory of Open Access Journals (Sweden)

    Nasser Fegh-hi Farahmand

    2013-01-01

    Full Text Available The article supports previous evidence that, even in host environments with high cultural distance and constraining employment frameworks, engineering planning, engineering are able to find room for engineering management maneuver. Specific attention paid to the transfer of the headquarters‘ flat organizational structure to a body of organizations with a noticeably hierarchical managerial system. This paper explore the ways in which certain characteristics in case of organizations generates a tendency to prepare a formal written engineering plan and focus is primarily on what describe as the environmental characteristics. Engineering excellence for strategic engineering includes also tools for financial, human resource, and risk management, as well as technology management, acquisitions and marketing. In other words, as has been suggested elsewhere, every national organizational system  even one as constrained engineering strategic approach as organizational necessary   contains some degree of malleability and openness which may be exploited through appropriate organization specific managerial strategies for engineering management.

  14. Social Engineering a General Approach

    Directory of Open Access Journals (Sweden)

    Valerica GREAVU-SERBAN

    2014-01-01

    Full Text Available Social engineering is considered to be a taboo subject in nowadays society. It involves the use of social skills or to obtain usernames, passwords, credit card data, or to compromise or altering the information and systems of an entity. Social engineering methods are numerous and people using it are extremely ingenious and adaptable. This technique takes advantage of the intrinsic nature of mankind, to manipulate and obtain sensitive information, persuading people into divulge it, using exceptional communication skills. Thus, five models of persuasion were identified, based on: simplicity, interest, incongruity, confidence and empathy, exploiting key factors which predispose people to fall victim to attacks of social engineering such as greed, self-interest, guilt or ignorance. It is well known fact that security is as strong as the weakest link in its chain (individuals therefore, beyond technical measures, staff training is the key to success in defending against such attacks.

  15. Advanced computational approaches to biomedical engineering

    CERN Document Server

    Saha, Punam K; Basu, Subhadip

    2014-01-01

    There has been rapid growth in biomedical engineering in recent decades, given advancements in medical imaging and physiological modelling and sensing systems, coupled with immense growth in computational and network technology, analytic approaches, visualization and virtual-reality, man-machine interaction and automation. Biomedical engineering involves applying engineering principles to the medical and biological sciences and it comprises several topics including biomedicine, medical imaging, physiological modelling and sensing, instrumentation, real-time systems, automation and control, sig

  16. Externally heated valve engine a new approach to piston engines

    CERN Document Server

    Kazimierski, Zbyszko

    2016-01-01

    This book reports on a novel approach for generating mechanical energy from different, external heat sources using the body of a typical piston engine with valves. By presenting simple yet effective numerical models, the authors show how this new approach, which combines existing internal combustion technology with a lubrication system, is able to offer an economic solution to the problem of mechanical energy generation in piston engines. Their results also show that a stable heat generation process can be guaranteed outside of the engine. The book offers a detailed report on physical and numerical models of 4-stroke and 2-stroke versions of the EHVE together with different models of heat exchange, valves and results of their simulations. It also delivers the test results of an engine prototype run in laboratory conditions. By presenting a novel theoretical framework and providing readers with extensive knowledge of both the advantages and challenges of the method, this book is expected to inspire academic re...

  17. Distributed simulation a model driven engineering approach

    CERN Document Server

    Topçu, Okan; Oğuztüzün, Halit; Yilmaz, Levent

    2016-01-01

    Backed by substantive case studies, the novel approach to software engineering for distributed simulation outlined in this text demonstrates the potent synergies between model-driven techniques, simulation, intelligent agents, and computer systems development.

  18. Thought-evoking approaches in engineering problems

    CERN Document Server

    2014-01-01

    In creating the value-added product in not distant future, it is necessary and inevitable to establish a holistic and though-evoking approach to the engineering problem, which should be at least associated with the inter-disciplinary knowledge and thought processes across the whole engineering spheres. It is furthermore desirable to integrate it with trans-disciplinary aspects ranging from manufacturing culture, through liberal-arts engineering, and industrial sociology.   The thought-evoking approach can be exemplified and typified by representative engineering problems: unveiling essential features in ‘Tangential Force Ratio and Interface Pressure’, prototype development for ‘Bio-mimetic Needle’ and application of ‘Water-jet Machining to Artificial Hip Joint’, product innovation in ‘Heat Sink for Computer’, application of ‘Graph Theory’ to similarity evaluation of production systems, leverage among reciprocity attributes in ‘Industrial and Engineering Designs for Machine Enclosure’,...

  19. Engineering design: A cognitive process approach

    Science.gov (United States)

    Strimel, Greg Joseph

    research objectives of this study. Two independent coders then coded the video/audio recordings and the additional design data using Halfin's (1973) 17 mental processes for technological problem-solving. The results of this study indicated that the participants employed a wide array of mental processes when solving engineering design challenges. However, the findings provide a general analysis of the number of times participants employed each mental process, as well as the amount of time consumed employing the various mental processes through the different stages of the engineering design process. The results indicated many similarities between the students solving the problem, which may highlight voids in current technology and engineering education curricula. Additionally, the findings showed differences between the processes employed by participants that created the most successful solutions and the participants who developed the least effective solutions. Upon comparing and contrasting these processes, recommendations for instructional strategies to enhance a student's capability for solving engineering design problems were developed. The results also indicated that students, when left without teacher intervention, use a simplified and more natural process to solve design challenges than the 12-step engineering design process reported in much of the literature. Lastly, these data indicated that students followed two different approaches to solving the design problem. Some students employed a sequential and logical approach, while others employed a nebulous, solution centered trial-and-error approach to solving the problem. In this study the participants who were more sequential had better performing solutions. Examining these two approaches and the student cognition data enabled the researcher to generate a conceptual engineering design model for the improved teaching and development of engineering design problem solving.

  20. Multiscale-multiphysics approaches for engineering applications

    Science.gov (United States)

    Pozzetti, Gabriele; Peters, Bernhard

    2017-07-01

    Engineering applications often require the study of complex Multiphysics systems. In order to provide solutions for problems of industrial-environmental interest, methods that can capture the influence of all the different scales of composite phenomena must be developed. Due to these necessities multiscale and multiphysics approaches are rapidly becoming a standard in the mathematical-numerical description of engineering systems. The goal of the symposium is to bring together industrial and environmental researcher and practitioners, in order to discuss techniques that aim to solve this kind of heterogeneous problem in an highly efficient way.

  1. Aerospace concurrent engineering: a modern global approach

    Science.gov (United States)

    Imbert, Mariano; Li, Xiaoxing

    2009-12-01

    System engineering aspects, like concurrent engineering (CE) in the aerospace sector, has been studied by many authors. The change and evolution in this regard is continually influenced by the information technology advances. But global cooperation is only discussed by developed countries and high technology corporations. A review of CE and its ramifications in the aerospace industry is presented. Based on the current literature, the general lifecycle of a spacecraft and its phases are explained as well as the tools that are implemented in today's industry. In this paper we propose a new approach for the product development process in the spacecraft production industry the Aerospace Concurrent Engineering (ACE), which is mainly focused in the technology itself, its optimal design and environment impact rather than costs and marketing impact. And the potential of globally oriented research and implementation of space programs is discussed for its consideration.

  2. Enterprise architecture approach to mining companies engineering

    Directory of Open Access Journals (Sweden)

    Ilin’ Igor

    2017-01-01

    Full Text Available As Russian economy is still largely oriented on commodities production, there are a lot of cities where mining and commodity-oriented enterprises are the backbone of city economy. The mentioned enterprises mostly define the life quality of citizens in such cities, thus there are high requirements for engineering of city-forming enterprises. The paper describes the enterprise architecture approach for management system engineering of the mining enterprises. The paper contains the model of the mining enterprise architecture, the approach to the development and implementation of an integrated management system based on the concept of enterprise architecture and the structure of information systems and information technology infrastructure of the mining enterprise.

  3. Engineering electrical properties of graphene: chemical approaches

    Science.gov (United States)

    Kim, Yong-Jin; Kim, Yuna; Novoselov, Konstantin; Hong, Byung Hee

    2015-12-01

    To ensure the high performance of graphene-based devices, it is necessary to engineer the electrical properties of graphene with enhanced conductivity, controlled work function, opened or closed bandgaps, etc. This can be performed by various non-covalent chemical approaches, including molecular adsorption, substrate-induced doping, polymerization on graphene, deposition of metallic thin films or nanoparticles, etc. In addition, covalent approaches such as the substitution of carbon atoms with boron or nitrogen and the functionalization with hydrogen or fluorine are useful to tune the bandgaps more efficiently, with better uniformity and stability. In this review, representative examples of chemically engineered graphene and its device applications will be reviewed, and remaining challenges will be discussed.

  4. Approaches and methodologies for mobile software engineering

    Directory of Open Access Journals (Sweden)

    Serena Pastore

    2015-09-01

    Full Text Available The development of software for mobile devices takes place in a dynamic environment where constraints, technologies and user needs change very frequently requiring enhanced approaches and methodologies in software engineering essential to deal with the concept of bring your own device (BYOD. Mobile apps are developed for various purposes in different categories. This paper discusses about the challenges that affect mobile software engineering, specifically for a science educational and outreach aim as regards technologies, approaches and methodologies that could be applied to unlock the full potential of mobility. In particular, it analyzes the main challenges to development in this field, such as dealing with enhanced connectivity and networking protocols (e.g., from Bluetooth Low Energy, IEEE 802.15.4-based protocols and new Wi-Fi versions and the fragmented ecosystem of mobile platforms. Moreover, it addresses the possible application of specific development methodologies such as Agile software methods.

  5. Comparing Two Approaches for Engineering Education Development

    DEFF Research Database (Denmark)

    Edström, Kristina; Kolmos, Anette

    2012-01-01

    and differences. CDIO and PBL will each be defined and compared in terms of the original need analysis, underlying educational philosophy and the essentials of the respective approaches to engineering education. In these respects we see many similarities. Circumstances that explain differences in history...... can learn from the other, as well as provide a chart for anyone who wishes to learn about any of these models. As a conclusion, some observations on common lessons learned will be made....

  6. A POGIL approach to teaching engineering hydrology

    Science.gov (United States)

    Rutten, M.

    2012-12-01

    This paper presents a case study of the author's experience using Problem Guided Inquiry Learning (POGIL) in an engineering hydrology course. This course is part of an interdisciplinary Water Management program at Bachelor level in the Netherlands. The aims of this approach were to promote constructivism of knowledge, activate critical thinking and reduce math anxiety. POGIL was developed for chemistry education in the United States. To the authors knowledge this is the first application of this approach in Europe. A first trial was done in 2010-2011 and a second trial in 2011-2012 and 55 students participated. The problems that motivated the novel approach, general information on POGIL, its implementation in the course are discussed and the results so far are evaluated.

  7. Nanofluids for heat transfer: an engineering approach.

    Science.gov (United States)

    Timofeeva, Elena V; Yu, Wenhua; France, David M; Singh, Dileep; Routbort, Jules L

    2011-02-28

    An overview of systematic studies that address the complexity of nanofluid systems and advance the understanding of nanoscale contributions to viscosity, thermal conductivity, and cooling efficiency of nanofluids is presented. A nanoparticle suspension is considered as a three-phase system including the solid phase (nanoparticles), the liquid phase (fluid media), and the interfacial phase, which contributes significantly to the system properties because of its extremely high surface-to-volume ratio in nanofluids. The systems engineering approach was applied to nanofluid design resulting in a detailed assessment of various parameters in the multivariable nanofluid systems. The relative importance of nanofluid parameters for heat transfer evaluated in this article allows engineering nanofluids with desired set of properties.

  8. Nanofluids for heat transfer: an engineering approach

    Directory of Open Access Journals (Sweden)

    France David

    2011-01-01

    Full Text Available Abstract An overview of systematic studies that address the complexity of nanofluid systems and advance the understanding of nanoscale contributions to viscosity, thermal conductivity, and cooling efficiency of nanofluids is presented. A nanoparticle suspension is considered as a three-phase system including the solid phase (nanoparticles, the liquid phase (fluid media, and the interfacial phase, which contributes significantly to the system properties because of its extremely high surface-to-volume ratio in nanofluids. The systems engineering approach was applied to nanofluid design resulting in a detailed assessment of various parameters in the multivariable nanofluid systems. The relative importance of nanofluid parameters for heat transfer evaluated in this article allows engineering nanofluids with desired set of properties.

  9. Nanofluids for heat transfer : an engineering approach.

    Energy Technology Data Exchange (ETDEWEB)

    Timofeeva, E. V.; Yu, W.; France, D. M.; Singh, D.; Routbort, J. L. (Energy Systems); ( NE); (Univ. of Illinois at Chicago)

    2011-02-28

    An overview of systematic studies that address the complexity of nanofluid systems and advance the understanding of nanoscale contributions to viscosity, thermal conductivity, and cooling efficiency of nanofluids is presented. A nanoparticle suspension is considered as a three-phase system including the solid phase (nanoparticles), the liquid phase (fluid media), and the interfacial phase, which contributes significantly to the system properties because of its extremely high surface-to-volume ratio in nanofluids. The systems engineering approach was applied to nanofluid design resulting in a detailed assessment of various parameters in the multivariable nanofluid systems. The relative importance of nanofluid parameters for heat transfer evaluated in this article allows engineering nanofluids with desired set of properties.

  10. The engineering approach to winter sports

    CERN Document Server

    Cheli, Federico; Maldifassi, Stefano; Melzi, Stefano; Sabbioni, Edoardo

    2016-01-01

    The Engineering Approach to Winter Sports presents the state-of-the-art research in the field of winter sports in a harmonized and comprehensive way for a diverse audience of engineers, equipment and facilities designers, and materials scientists. The book examines the physics and chemistry of snow and ice with particular focus on the interaction (friction) between sports equipment and snow/ice, how it is influenced by environmental factors, such as temperature and pressure, as well as by contaminants and how it can be modified through the use of ski waxes or the microtextures of blades or ski soles. The authors also cover, in turn, the different disciplines in winter sports:  skiing (both alpine and cross country), skating and jumping, bob sledding and skeleton, hockey and curling, with attention given to both equipment design and on the simulation of gesture and  track optimization.

  11. Project Supervision – An Engineering Approach

    DEFF Research Database (Denmark)

    Paulsen, Rasmus Reinhold; Larsen, Rasmus; Ersbøll, Bjarne Kjær

    2011-01-01

    of their master thesis writing. The supervision principles are: Ownership: The student should feel that their project is their own. Ideally, they should formulate the project themselves. Write early: We strongly encourage the students to write and generate figures and images already from the first week......For more than twenty years, a group based supervision strategy has been used when supervising engineering bachelor- and master thesis students at our research group. In recent years, we have formalised the approach and used our industry experience to create a very successful framework for project...... at all meetings. Weekly meetings are scheduled to be at a specific day at a specific place for the entire process....

  12. APPROACHES TO ENGINEER STABILITY OF BEETLE LUCIFERASES

    Directory of Open Access Journals (Sweden)

    Mikhail I. Koksharov

    2012-09-01

    Full Text Available Luciferase enzymes from fireflies and other beetles have many important applications in molecular biology, biotechnology, analytical chemistry and several other areas. Many novel beetle luciferases with promising properties have been reported in the recent years. However, actual and potential applications of wild-type beetle luciferases are often limited by insufficient stability or decrease in activity of the enzyme at the conditions of a particular assay. Various examples of genetic engineering of the enhanced beetle luciferases have been reported that successfully solve or alleviate many of these limitations. This mini-review summarizes the recent advances in development of mutant luciferases with improved stability and activity characteristics. It discusses the common limitations of wild-type luciferases in different applications and presents the efficient approaches that can be used to address these problems.

  13. Approaches to engineer stability of beetle luciferases

    Directory of Open Access Journals (Sweden)

    Mikhail Koksharov

    2012-09-01

    Full Text Available Luciferase enzymes from fireflies and other beetles have many important applications in molecular biology, biotechnology, analytical chemistry and several other areas. Many novel beetle luciferases with promising properties have been reported in the recent years. However, actual and potential applications of wild-type beetle luciferases are often limited by insufficient stability or decrease in activity of the enzyme at the conditions of a particular assay. Various examples of genetic engineering of the enhanced beetle luciferases have been reported that successfully solve or alleviate many of these limitations. This mini-review summarizes the recent advances in development of mutant luciferases with improved stability and activity characteristics. It discusses the common limitations of wild-type luciferases in different applications and presents the efficient approaches that can be used to address these problems.

  14. Combined additive manufacturing approaches in tissue engineering.

    Science.gov (United States)

    Giannitelli, S M; Mozetic, P; Trombetta, M; Rainer, A

    2015-09-01

    Advances introduced by additive manufacturing (AM) have significantly improved the control over the microarchitecture of scaffolds for tissue engineering. This has led to the flourishing of research works addressing the optimization of AM scaffolds microarchitecture to optimally trade-off between conflicting requirements (e.g. mechanical stiffness and porosity level). A fascinating trend concerns the integration of AM with other scaffold fabrication methods (i.e. "combined" AM), leading to hybrid architectures with complementary structural features. Although this innovative approach is still at its beginning, significant results have been achieved in terms of improved biological response to the scaffold, especially targeting the regeneration of complex tissues. This review paper reports the state of the art in the field of combined AM, posing the accent on recent trends, challenges, and future perspectives.

  15. Combinatorial and high-throughput screening approaches for strain engineering.

    Science.gov (United States)

    Liu, Wenshan; Jiang, Rongrong

    2015-03-01

    Microbes have long been used in the industry to produce valuable biochemicals. Combinatorial engineering approaches, new strain engineering tools derived from inverse metabolic engineering, have started to attract attention in recent years, including genome shuffling, error-prone DNA polymerase, global transcription machinery engineering (gTME), random knockout/overexpression libraries, ribosome engineering, multiplex automated genome engineering (MAGE), customized optimization of metabolic pathways by combinatorial transcriptional engineering (COMPACTER), and library construction of "tunable intergenic regions" (TIGR). Since combinatorial approaches and high-throughput screening methods are fundamentally interconnected, color/fluorescence-based, growth-based, and biosensor-based high-throughput screening methods have been reviewed. We believe that with the help of metabolic engineering tools and new combinatorial approaches, plus effective high-throughput screening methods, researchers will be able to achieve better results on improving microorganism performance under stress or enhancing biochemical yield.

  16. Software quality engineering a practitioner's approach

    CERN Document Server

    Suryn, Witold

    2014-01-01

    Software quality stems from two distinctive, but associated, topics in software engineering: software functional quality and software structural quality. Software Quality Engineering studies the tenets of both of these notions, which focus on the efficiency and value of a design, respectively. The text addresses engineering quality on both the application and system levels with attention to Information Systems and Embedded Systems as well as recent developments. Targeted at graduate engineering students and software quality specialists, the book analyzes the relationship between functionality

  17. Applying Agile Requirements Engineering Approach for Re-engineering & Changes in existing Brownfield Adaptive Systems

    OpenAIRE

    Masood, Abdullah; Ali, M. Asim

    2014-01-01

    Requirements Engineering (RE) is a key activity in the development of software systems and is concerned with the identification of the goals of stakeholders and their elaboration into precise statements of desired services and behavior. The research describes an Agile Requirements Engineering approach for re-engineering & changes in existing Brownfield adaptive system. The approach has few modifications that can be used as a part of SCRUM development process for re-engineering & changes. The ...

  18. Global Software Engineering: A Software Process Approach

    Science.gov (United States)

    Richardson, Ita; Casey, Valentine; Burton, John; McCaffery, Fergal

    Our research has shown that many companies are struggling with the successful implementation of global software engineering, due to temporal, cultural and geographical distance, which causes a range of factors to come into play. For example, cultural, project managementproject management and communication difficulties continually cause problems for software engineers and project managers. While the implementation of efficient software processes can be used to improve the quality of the software product, published software process models do not cater explicitly for the recent growth in global software engineering. Our thesis is that global software engineering factors should be included in software process models to ensure their continued usefulness in global organisations. Based on extensive global software engineering research, we have developed a software process, Global Teaming, which includes specific practices and sub-practices. The purpose is to ensure that requirements for successful global software engineering are stipulated so that organisations can ensure successful implementation of global software engineering.

  19. A modular approach to cardiac tissue engineering.

    Science.gov (United States)

    Leung, Brendan M; Sefton, Michael V

    2010-10-01

    Functional cardiac tissue was prepared using a modular tissue engineering approach with the goal of creating vascularized tissue. Rat aortic endothelial cells (RAEC) were seeded onto submillimeter-sized modules made of type I bovine collagen supplemented with Matrigel™ (25% v/v) embedded with cardiomyocyte (CM)-enriched neonatal rat heart cells and assembled into a contractile, macroporous, sheet-like construct. Modules (without RAEC) cultured in 10% bovine serum (BS) were more contractile and responsive to external stimulus (lower excitation threshold, higher maximum capture rate, and greater en face fractional area changes) than modules cultured in 10% fetal BS. Incorporating 25% Matrigel in the matrix reduced the excitation threshold and increased the fractional area change relative to collagen only modules (without RAEC). A coculture medium, containing 10% BS, low Mg2+ (0.814mM), and normal glucose (5.5mM), was used to maintain RAEC junction morphology (VE-cadherin) and CM contractility, although the responsiveness of CM was attenuated with RAEC on the modules. Macroporous, sheet-like module constructs were assembled by partially immobilizing a layer of modules in alginate gel until day 8, with or without RAEC. RAEC/CM module sheets were electrically responsive; however, like modules with RAEC this responsiveness was attenuated relative to CM-only sheets. Muscle bundles coexpressing cardiac troponin I and connexin-43 were evident near the perimeter of modules and at intermodule junctions. These results suggest the potential of the modular approach as a platform for building vascularized cardiac tissue.

  20. An Approach to Design Reusable Workflow Engine

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Developers still need design workflow system according to users' specific needs, though workflow management coalition standardized the five kinds of abstract interfaces in workflow reference model. Specific business process characteristics are still supported by specific workflow system. A set of common functionalities of workflow engine are abstracted from business component, so the reusability of business component is extended into workflow engine and composition method is proposed. Needs of different business requirements and characteristics are met by reusing the workflow engine.

  1. Engineering Students' Sustainability Approaches

    Science.gov (United States)

    Haase, S.

    2014-01-01

    Sustainability issues are increasingly important in engineering work all over the world. This article explores systematic differences in self-assessed competencies, interests, importance, engagement and practices of newly enrolled engineering students in Denmark in relation to environmental and non-environmental sustainability issues. The…

  2. An alternative Approach to Power Engineering

    DEFF Research Database (Denmark)

    Pedersen, Knud Ole Helgesen; Havemann (retired June, 2000), Henrik

    2000-01-01

    In a drive to attract more students, three new courses have been introduced at the Department of Electric Power Engineering of the Technical University of Denmark. Among many students, power engineering has a reputation of being old-fashioned and static, whereas information technology is regarded...

  3. Protein engineering approaches to chemical biotechnology.

    Science.gov (United States)

    Chen, Zhen; Zeng, An-Ping

    2016-12-01

    Protein engineering for the improvement of properties of biocatalysts and for the generation of novel metabolic pathways plays more and more important roles in chemical biotechnology aiming at the production of chemicals from biomass. Although widely used in single-enzyme catalysis process, protein engineering is only being increasingly explored in recent years to achieve more complex in vitro and in vivo biocatalytic processes. This review focuses on major contributions of protein engineering to chemical biotechnology in the field of multi-enzymatic cascade catalysis and metabolic engineering. Especially, we discuss and highlight recent strategies for combining pathway design and protein engineering for the production of novel products. Copyright © 2016. Published by Elsevier Ltd.

  4. An integrated turbocharger design approach to improve engine performance

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Turbocharging technology is today considered as a promising way for internal combustion engine energy saving and CO2 reduction.Turbocharger design is a major challenge for turbocharged engine performance improvement.The turbocharger designer must draw upon the information of engine operation conditions,and an appropriate link between the engine requirements and design features must be carefully developed to generate the most suitable design recommendation.The objective of this research is to develop a turbocharger design approach for better turbocharger matching to an internal combustion engine.The development of the approach is based on the concept of turbocharger design and interaction links between engine cycle requirements and design parameter values.A turbocharger through flow model is then used to generate the design alternatives.This integrated method has been applied with success to a gasoline engine turbocharger assembly.

  5. Knowledge Engineering Approach to the Geotectonic Discourse

    Science.gov (United States)

    Pshenichny, Cyril

    2014-05-01

    The intellectual challenge of geotectonics is, and always was, much harder than that of most of the sciences: geotectonics has to say much when there is objectively not too much to say. As the target of study (the genesis of regional and planetary geological structures) is vast and multidisciplinary and is more or less generic for many geological disciplines, its more or less complete description is practically inachievable. Hence, the normal pathway of natural-scientific research - first acquire data, then draw conclusion - unlikely can be the case here. Geotectonics does quite the opposite; its approach is purely abductive: first to suggest a conceptualization (hypothesis) based on some external grounds (either general planetary/cosmic/philosophic/religious considerations, or based on experience gained from research of other structures/regions/planets) and then to acquire data that either support or refute it. In fact, geotectonics defines the context for data acquisition, and hence, the paradigm for the entire body of geology. Being an obvious necessity for a descriptive science, this nevertheless creates a number of threats: • Like any people, scientists like simplicity and unity, and therefore a single geotectonic hypothesis may seem preferable once based on the data available at the moment and oppress other views which may acquire evidence in the future; • As impartial data acquisition is rather a myth than reality even in most of the natural sciences, in a study like geology this process becomes strongly biased by the reigning hypothesis and controlled to supply only supportive evidence; • It becomes collectively agreed that any, or great many, domains of geological knowledge are determined by a geotectonic concept, which is, in turn, offered by a reigning hypothesis (sometimes reclassified as theory) - e.g., exploration geologists must involve the global geotectonic terminology in their technical reports on assessment of mineral or hydrocarbon

  6. Modular co-culture engineering, a new approach for metabolic engineering.

    Science.gov (United States)

    Zhang, Haoran; Wang, Xiaonan

    2016-09-01

    With the development of metabolic engineering, employment of a selected microbial host for accommodation of a designed biosynthetic pathway to produce a target compound has achieved tremendous success in the past several decades. Yet, increasing requirements for sophisticated microbial biosynthesis call for establishment and application of more advanced metabolic engineering methodologies. Recently, important progress has been made towards employing more than one engineered microbial strains to constitute synthetic co-cultures and modularizing the biosynthetic labor between the co-culture members in order to improve bioproduction performance. This emerging approach, referred to as modular co-culture engineering in this review, presents a valuable opportunity for expanding the scope of the broad field of metabolic engineering. We highlight representative research accomplishments using this approach, especially those utilizing metabolic engineering tools for microbial co-culture manipulation. Key benefits and major challenges associated with modular co-culture engineering are also presented and discussed.

  7. Interdisciplinary Approach to Software Engineering Education

    Directory of Open Access Journals (Sweden)

    Alfred Schaetter

    2009-10-01

    Full Text Available One of the most serious problems in software engineering projects is the communication between users and developers. It is widely recognized that communication problems are a major factor in the delay and failure of software projects. During university education, students are usually well-skilled in programming languages, hard- and software engineering tools and project management. This paper provides theoretical background and some successful examples how we train our students under 'real world' conditions within software projects at the university e.g. to work in teams or to communicate with different stakeholders? Both method and employability result in excellent ratings.

  8. Interdisciplinary Approach to Software Engineering Education

    Directory of Open Access Journals (Sweden)

    Karlheinz Blankenbach

    2009-10-01

    Full Text Available One of the most serious problems in software engineering projects is the communication between users and developers. It is widely recognized that communication problems are a major factor in the delay and failure of software projects. During university education, students are usually well-skilled in programming languages, hard- and software engineering tools and project management. This paper provides theoretical background and some successful examples how we train our students under 'real world' conditions within software projects at the university e.g. to work in teams or to communicate with different stakeholders? Both method and employability result in excellent ratings.

  9. Performance optimization of Jatropha biodiesel engine model using Taguchi approach

    Energy Technology Data Exchange (ETDEWEB)

    Ganapathy, T.; Murugesan, K.; Gakkhar, R.P. [Mechanical and Industrial Engineering Department, Indian Institute of Technology Roorkee, Roorkee 247 667 (India)

    2009-11-15

    This paper proposes a methodology for thermodynamic model analysis of Jatropha biodiesel engine in combination with Taguchi's optimization approach to determine the optimum engine design and operating parameters. A thermodynamic model based on two-zone Weibe's heat release function has been employed to simulate the Jatropha biodiesel engine performance. Among the important engine design and operating parameters 10 critical parameters were selected assuming interactions between the pair of parameters. Using linear graph theory and Taguchi method an L{sub 16} orthogonal array has been utilized to determine the engine test trials layout. In order to maximize the performance of Jatropha biodiesel engine the signal to noise ratio (SNR) related to higher-the-better (HTB) quality characteristics has been used. The present methodology correctly predicted the compression ratio, Weibe's heat release constants and combustion zone duration as the critical parameters that affect the performance of the engine compared to other parameters. (author)

  10. Biomedical Engineering Education: A Conservative Approach

    Science.gov (United States)

    Niemi, Eugene E., Jr.

    1973-01-01

    Describes the demand for graduates from biomedical engineering programs as being not yet fully able to absorb the supply. Suggests small schools interested in entering the field consider offering their programs at the undergraduate level via a minor or an option. Examples of such options and student projects are included. (CC)

  11. Design Approaches and Comparison of TAPS Packages for Engineering

    Science.gov (United States)

    Sidhu, S. Manjit

    2007-01-01

    Purpose: The paper's purpose is to promote the use of modern technologies such as multimedia packages to engineering students. The aim is to help them to learning in their learning, visualization, problem solving and understanding engineering concepts such as in mechanics dynamics. Design/methodology/approach: TAPS packages are developed to help…

  12. The JPL Cost Risk Analysis Approach that Incorporates Engineering Realism

    Science.gov (United States)

    Harmon, Corey C.; Warfield, Keith R.; Rosenberg, Leigh S.

    2006-01-01

    This paper discusses the JPL Cost Engineering Group (CEG) cost risk analysis approach that accounts for all three types of cost risk. It will also describe the evaluation of historical cost data upon which this method is based. This investigation is essential in developing a method that is rooted in engineering realism and produces credible, dependable results to aid decision makers.

  13. The JPL Cost Risk Analysis Approach that Incorporates Engineering Realism

    Science.gov (United States)

    Harmon, Corey C.; Warfield, Keith R.; Rosenberg, Leigh S.

    2006-01-01

    This paper discusses the JPL Cost Engineering Group (CEG) cost risk analysis approach that accounts for all three types of cost risk. It will also describe the evaluation of historical cost data upon which this method is based. This investigation is essential in developing a method that is rooted in engineering realism and produces credible, dependable results to aid decision makers.

  14. Design Approaches and Comparison of TAPS Packages for Engineering

    Science.gov (United States)

    Sidhu, S. Manjit

    2007-01-01

    Purpose: The paper's purpose is to promote the use of modern technologies such as multimedia packages to engineering students. The aim is to help them to learning in their learning, visualization, problem solving and understanding engineering concepts such as in mechanics dynamics. Design/methodology/approach: TAPS packages are developed to help…

  15. System engineering approach to planning anticancer therapies

    CERN Document Server

    Świerniak, Andrzej; Smieja, Jaroslaw; Puszynski, Krzysztof; Psiuk-Maksymowicz, Krzysztof

    2016-01-01

    This book focuses on the analysis of cancer dynamics and the mathematically based synthesis of anticancer therapy. It summarizes the current state-of-the-art in this field and clarifies common misconceptions about mathematical modeling in cancer. Additionally, it encourages closer cooperation between engineers, physicians and mathematicians by showing the clear benefits of this without stating unrealistic goals. Development of therapy protocols is realized from an engineering point of view, such as the search for a solution to a specific control-optimization problem. Since in the case of cancer patients, consecutive measurements providing information about the current state of the disease are not available, the control laws are derived for an open loop structure. Different forms of therapy are incorporated into the models, from chemotherapy and antiangiogenic therapy to immunotherapy and gene therapy, but the class of models introduced is broad enough to incorporate other forms of therapy as well. The book be...

  16. Agent Based Approaches to Engineering Autonomous Space Software

    CERN Document Server

    Dennis, Louise A; Lincoln, Nicholas; Lisitsa, Alexei; Veres, Sandor M

    2010-01-01

    Current approaches to the engineering of space software such as satellite control systems are based around the development of feedback controllers using packages such as MatLab's Simulink toolbox. These provide powerful tools for engineering real time systems that adapt to changes in the environment but are limited when the controller itself needs to be adapted. We are investigating ways in which ideas from temporal logics and agent programming can be integrated with the use of such control systems to provide a more powerful layer of autonomous decision making. This paper will discuss our initial approaches to the engineering of such systems.

  17. APPROACH TO MANAGEMENT PERSONNEL AT MECHANICAL ENGINEERING ENTERPRISES

    Directory of Open Access Journals (Sweden)

    Sogomonyan T. K.

    2015-11-01

    Full Text Available The article considers the existing at the present stage of management approaches, describes their advantages and disadvantages. We have obtained scientific and special management approaches. Of all the approaches described in detail, we could highlight system, integration, dynamic, structural, functional and process approaches. It was indicated, that the use of the above approach to production management, as a whole, and the staff in particular - is limited to the economic sphere of activity, meanwhile, as there is a prospect of using these approaches in the field of labor protection. We also substantiate the choice process approach as the most promising in the management staff of mechanical engineering enterprise

  18. Systems engineering: A formal approach. Part 1: System concepts

    Science.gov (United States)

    Vanhee, K. M.

    1993-03-01

    Engineering is the scientific discipline focused on the creation of new artifacts that are supposed to be of some use to our society. Different types of artifacts require different engineering approaches. However, in all these disciplines the development of a new artifact is divided into stages. Three stages can always be recognized: Analysis, Design, and Realization. The book considers only the first two stages of the development process. It focuses on a specific type of artifacts, called discrete dynamic systems. These systems consist of active components of actors that consume and produce passive components or tokens. Three subtypes are studied in more detail: business systems (like a factory or restaurant), information systems (whether automated or not), and automated systems (systems that are controlled by an automated information system). The first subtype is studied by industrial engineers, the last by software engineers and electrical engineers, whereas the second is a battlefield for all three disciplines. The union of these disciplines is called systems engineering.

  19. An algebraic approach to modeling in software engineering

    Energy Technology Data Exchange (ETDEWEB)

    Loegel, G.J. [Superconducting Super Collider Lab., Dallas, TX (United States)]|[Michigan Univ., Ann Arbor, MI (United States); Ravishankar, C.V. [Michigan Univ., Ann Arbor, MI (United States)

    1993-09-01

    Our work couples the formalism of universal algebras with the engineering techniques of mathematical modeling to develop a new approach to the software engineering process. Our purpose in using this combination is twofold. First, abstract data types and their specification using universal algebras can be considered a common point between the practical requirements of software engineering and the formal specification of software systems. Second, mathematical modeling principles provide us with a means for effectively analyzing real-world systems. We first use modeling techniques to analyze a system and then represent the analysis using universal algebras. The rest of the software engineering process exploits properties of universal algebras that preserve the structure of our original model. This paper describes our software engineering process and our experience using it on both research and commercial systems. We need a new approach because current software engineering practices often deliver software that is difficult to develop and maintain. Formal software engineering approaches use universal algebras to describe ``computer science`` objects like abstract data types, but in practice software errors are often caused because ``real-world`` objects are improperly modeled. There is a large semantic gap between the customer`s objects and abstract data types. In contrast, mathematical modeling uses engineering techniques to construct valid models for real-world systems, but these models are often implemented in an ad hoc manner. A combination of the best features of both approaches would enable software engineering to formally specify and develop software systems that better model real systems. Software engineering, like mathematical modeling, should concern itself first and foremost with understanding a real system and its behavior under given circumstances, and then with expressing this knowledge in an executable form.

  20. A genetic engineering approach to genetic algorithms.

    Science.gov (United States)

    Gero, J S; Kazakov, V

    2001-01-01

    We present an extension to the standard genetic algorithm (GA), which is based on concepts of genetic engineering. The motivation is to discover useful and harmful genetic materials and then execute an evolutionary process in such a way that the population becomes increasingly composed of useful genetic material and increasingly free of the harmful genetic material. Compared to the standard GA, it provides some computational advantages as well as a tool for automatic generation of hierarchical genetic representations specifically tailored to suit certain classes of problems.

  1. Combining engineering and data-driven approaches

    DEFF Research Database (Denmark)

    Fischer, Katharina; De Sanctis, Gianluca; Kohler, Jochen

    2015-01-01

    assumptions that may result in a biased risk assessment. In two related papers we show how engineering and data-driven modelling can be combined by developing generic risk models that are calibrated to statistical data on observed fire events. The focus of the present paper is on the calibration procedure....... A framework is developed that is able to deal with data collection in non-homogeneous portfolios of buildings. Also incomplete data sets containing only little information on each fire event can be used for model calibration. To illustrate the capabilities of the proposed framework, it is applied...

  2. Radio systems engineering a tutorial approach

    CERN Document Server

    Santos, Héctor J De Los; Ponte, Juan

    2015-01-01

    This book is intended for readers who already have knowledge of devices and circuits for radio-frequency (RF) and microwave communication and are ready to study the systems engineering-level aspects of modern radio communications systems. The authors provide a general overview of radio systems with their components, focusing on the analog parts of the system and their non-idealities. Based on the physical functionality of the various building blocks of a modern radio system, block parameters are derived, which allows the examination of their influence on the overall system performance. The dis

  3. A Systems Engineering Approach to Architecture Development

    Science.gov (United States)

    Di Pietro, David A.

    2015-01-01

    Architecture development is often conducted prior to system concept design when there is a need to determine the best-value mix of systems that works collectively in specific scenarios and time frames to accomplish a set of mission area objectives. While multiple architecture frameworks exist, they often require use of unique taxonomies and data structures. In contrast, this paper characterizes architecture development using terminology widely understood within the systems engineering community. Using a notional civil space architecture example, it employs a multi-tier framework to describe the enterprise level architecture and illustrates how results of lower tier, mission area architectures integrate into the enterprise architecture. It also presents practices for conducting effective mission area architecture studies, including establishing the trade space, developing functions and metrics, evaluating the ability of potential design solutions to meet the required functions, and expediting study execution through the use of iterative design cycles

  4. Engine Icing Data - An Analytics Approach

    Science.gov (United States)

    Fitzgerald, Brooke A.; Flegel, Ashlie B.

    2017-01-01

    Engine icing researchers at the NASA Glenn Research Center use the Escort data acquisition system in the Propulsion Systems Laboratory (PSL) to generate and collect a tremendous amount of data every day. Currently these researchers spend countless hours processing and formatting their data, selecting important variables, and plotting relationships between variables, all by hand, generally analyzing data in a spreadsheet-style program (such as Microsoft Excel). Though spreadsheet-style analysis is familiar and intuitive to many, processing data in spreadsheets is often unreproducible and small mistakes are easily overlooked. Spreadsheet-style analysis is also time inefficient. The same formatting, processing, and plotting procedure has to be repeated for every dataset, which leads to researchers performing the same tedious data munging process over and over instead of making discoveries within their data. This paper documents a data analysis tool written in Python hosted in a Jupyter notebook that vastly simplifies the analysis process. From the file path of any folder containing time series datasets, this tool batch loads every dataset in the folder, processes the datasets in parallel, and ingests them into a widget where users can search for and interactively plot subsets of columns in a number of ways with a click of a button, easily and intuitively comparing their data and discovering interesting dynamics. Furthermore, comparing variables across data sets and integrating video data (while extremely difficult with spreadsheet-style programs) is quite simplified in this tool. This tool has also gathered interest outside the engine icing branch, and will be used by researchers across NASA Glenn Research Center. This project exemplifies the enormous benefit of automating data processing, analysis, and visualization, and will help researchers move from raw data to insight in a much smaller time frame.

  5. Engineering systems reliability, safety, and maintenance an integrated approach

    CERN Document Server

    Dhillon, B S

    2017-01-01

    Today, engineering systems are an important element of the world economy and each year billions of dollars are spent to develop, manufacture, operate, and maintain various types of engineering systems around the globe. Many of these systems are highly sophisticated and contain millions of parts. For example, a Boeing jumbo 747 is made up of approximately 4.5 million parts including fasteners. Needless to say, reliability, safety, and maintenance of systems such as this have become more important than ever before.  Global competition and other factors are forcing manufacturers to produce highly reliable, safe, and maintainable engineering products. Therefore, there is a definite need for the reliability, safety, and maintenance professionals to work closely during design and other phases. Engineering Systems Reliability, Safety, and Maintenance: An Integrated Approach eliminates the need to consult many different and diverse sources in the hunt for the information required to design better engineering syste...

  6. Failure of engineering artifacts: a life cycle approach.

    Science.gov (United States)

    Del Frate, Luca

    2013-09-01

    Failure is a central notion both in ethics of engineering and in engineering practice. Engineers devote considerable resources to assure their products will not fail and considerable progress has been made in the development of tools and methods for understanding and avoiding failure. Engineering ethics, on the other hand, is concerned with the moral and social aspects related to the causes and consequences of technological failures. But what is meant by failure, and what does it mean that a failure has occurred? The subject of this paper is how engineers use and define this notion. Although a traditional definition of failure can be identified that is shared by a large part of the engineering community, the literature shows that engineers are willing to consider as failures also events and circumstance that are at odds with this traditional definition. These cases violate one or more of three assumptions made by the traditional approach to failure. An alternative approach, inspired by the notion of product life cycle, is proposed which dispenses with these assumptions. Besides being able to address the traditional cases of failure, it can deal successfully with the problematic cases. The adoption of a life cycle perspective allows the introduction of a clearer notion of failure and allows a classification of failure phenomena that takes into account the roles of stakeholders involved in the various stages of a product life cycle.

  7. Optimisation of Multilayer Insulation an Engineering Approach

    CERN Document Server

    Chorowski, M; Parente, C; Riddone, G

    2001-01-01

    A mathematical model has been developed to describe the heat flux through multilayer insulation (MLI). The total heat flux between the layers is the result of three distinct heat transfer modes: radiation, residual gas conduction and solid spacer conduction. The model describes the MLI behaviour considering a layer-to-layer approach and is based on an electrical analogy, in which the three heat transfer modes are treated as parallel thermal impedances. The values of each of the transfer mode vary from layer to layer, although the total heat flux remains constant across the whole MLI blanket. The model enables the optimisation of the insulation with regard to different MLI parameters, such as residual gas pressure, number of layers and boundary temperatures. The model has been tested with experimental measurements carried out at CERN and the results revealed to be in a good agreement, especially for insulation vacuum between 10-5 Pa and 10-3 Pa.

  8. Recent advances in rational approaches for enzyme engineering

    Directory of Open Access Journals (Sweden)

    Kerstin Steiner

    2012-09-01

    Full Text Available Enzymes are an attractive alternative in the asymmetric syntheses of chiral building blocks. To meet the requirements of industrial biotechnology and to introduce new functionalities, the enzymes need to be optimized by protein engineering. This article specifically reviews rational approaches for enzyme engineering and de novo enzyme design involving structure-based approaches developed in recent years for improvement of the enzymes’ performance, broadened substrate range, and creation of novel functionalities to obtain products with high added value for industrial applications.

  9. An engineering approach to extending lifespan in C. elegans.

    Directory of Open Access Journals (Sweden)

    Dror Sagi

    Full Text Available We have taken an engineering approach to extending the lifespan of Caenorhabditis elegans. Aging stands out as a complex trait, because events that occur in old animals are not under strong natural selection. As a result, lifespan can be lengthened rationally using bioengineering to modulate gene expression or to add exogenous components. Here, we engineered longer lifespan by expressing genes from zebrafish encoding molecular functions not normally present in worms. Additionally, we extended lifespan by increasing the activity of four endogenous worm aging pathways. Next, we used a modular approach to extend lifespan by combining components. Finally, we used cell- and worm-based assays to analyze changes in cell physiology and as a rapid means to evaluate whether multi-component transgenic lines were likely to have extended longevity. Using engineering to add novel functions and to tune endogenous functions provides a new framework for lifespan extension that goes beyond the constraints of the worm genome.

  10. Approaches to Low Fuel Regression Rate in Hybrid Rocket Engines

    OpenAIRE

    Dario Pastrone

    2012-01-01

    Hybrid rocket engines are promising propulsion systems which present appealing features such as safety, low cost, and environmental friendliness. On the other hand, certain issues hamper the development hoped for. The present paper discusses approaches addressing improvements to one of the most important among these issues: low fuel regression rate. To highlight the consequence of such an issue and to better understand the concepts proposed, fundamentals are summarized. Two approaches are pre...

  11. Rational and random approaches to adenoviral vector engineering

    NARCIS (Netherlands)

    Uil, Taco Gilles

    2011-01-01

    The overall aim of this thesis is to contribute to the engineering of more selective and effective oncolytic Adenovirus (Ad) vectors. Two general approaches are taken for this purpose: (i) genetic capsid modification to achieve Ad retargeting (Chapters 2 to 4), and (ii) directed evolution to improve

  12. Agile Service Development: A Rule-Based Method Engineering Approach

    NARCIS (Netherlands)

    Hoppenbrouwers, Stijn; Zoet, Martijn; Versendaal, Johan; Weerd, Inge van de

    2011-01-01

    Agile software development has evolved into an increasingly mature software development approach and has been applied successfully in many software vendors’ development departments. In this position paper, we address the broader agile service development. Based on method engineering principles we de

  13. Chips for Everyone: A Multifaceted Approach in Electrical Engineering Outreach

    Science.gov (United States)

    Magill, J.; Roy, S.

    2010-01-01

    This paper reports on a multifaceted approach in electrical engineering outreach focused on the area of semiconductor technology. The activities developed can be used in combination for a very wide range of audiences in both age and stage of education, as has been demonstrated with great success. Moreover, the project has developed…

  14. Engineering system dynamics a unified graph-centered approach

    CERN Document Server

    Brown, Forbes T

    2006-01-01

    For today's students, learning to model the dynamics of complex systems is increasingly important across nearly all engineering disciplines. First published in 2001, Forbes T. Brown's Engineering System Dynamics: A Unified Graph-Centered Approach introduced students to a unique and highly successful approach to modeling system dynamics using bond graphs. Updated with nearly one-third new material, this second edition expands this approach to an even broader range of topics. What's New in the Second Edition? In addition to new material, this edition was restructured to build students' competence in traditional linear mathematical methods before they have gone too far into the modeling that still plays a pivotal role. New topics include magnetic circuits and motors including simulation with magnetic hysteresis; extensive new material on the modeling, analysis, and simulation of distributed-parameter systems; kinetic energy in thermodynamic systems; and Lagrangian and Hamiltonian methods. MATLAB(R) figures promi...

  15. Stirling engine - Approach for long-term durability assessment

    Science.gov (United States)

    Tong, Michael T.; Bartolotta, Paul A.; Halford, Gary R.; Freed, Alan D.

    1992-01-01

    The approach employed by NASA Lewis for the long-term durability assessment of the Stirling engine hot-section components is summarized. The approach consists of: preliminary structural assessment; development of a viscoplastic constitutive model to accurately determine material behavior under high-temperature thermomechanical loads; an experimental program to characterize material constants for the viscoplastic constitutive model; finite-element thermal analysis and structural analysis using a viscoplastic constitutive model to obtain stress/strain/temperature at the critical location of the hot-section components for life assessment; and development of a life prediction model applicable for long-term durability assessment at high temperatures. The approach should aid in the provision of long-term structural durability and reliability of Stirling engines.

  16. AN APPROACH TOWARDS HOLISM IN SCIENCE AND ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    Jason SHERWIN

    2010-01-01

    This paper posits the desirability of a shift towards a holistic approach over reductionist approaches in the understanding of complex phenomena encountered in science and engineering.An argument based on set theory is used to analyze three examples that illustrate the shortcomings of the reductionist approach.Using these cases as motivational points,a holistic approach to understand complex phenomena is proposed,whereby the human brain acts as a template to do so.Recognizing the need to maintain the transparency of the analysis provided by reductionism,a promising computational approach is offered by which the brain is used as a template for understanding complex phenomena.Some of the details of implementing this approach are also addressed.

  17. Educational Approach of Refactoring in Facilitating Reverse Engineering

    Directory of Open Access Journals (Sweden)

    Mazni Omar

    2010-05-01

    Full Text Available Refactoring improves software codes and design. This activity often neglected by software developers because they need time to decide tactically where and when to refactor codes. Although the concepts theoretically instilled in the developer’s mind, this activity is not easy to apply and visualize. This situation became more problematic when deals with inexperienced developers. Therefore, there is a need to develop an educational approach to comprehend refactoring activity.This activity was applied through reverse engineering tasks. Thesoftware engineering (SE teams were required to apply reverseengineering activity in order to check the consistency betweencodes and design. The teams were encouraged to apply Model-View-Controller (MVC pattern architecture in order to facilitatethe activities. Findings revealed that Extreme Programming (XPteams managed to complete reverse engineering tasks earlierthan Formal teams. This study found that the approach is important to increase understanding of refactoring activities in reverse engineering process. This approach will be furthered applied for others SE teams to gain more insight and perceptions towards improving SE course.

  18. A Rigorous Architectural Approach to Adaptive Software Engineering

    Institute of Scientific and Technical Information of China (English)

    Jeff Kramer; Jeff Magee

    2009-01-01

    The engineering of distributed adaptive software is a complex task which requires a rigorous approach. Software architectural (structural) concepts and principles are highly beneficial in specifying, designing, analysing, constructing and evolving distributed software. A rigorous architectural approach dictates formalisms and techniques that are compositional,components that are context independent and systems that can be constructed and evolved incrementally. This paper overviews some of the underlying reasons for adopting an architectural approach, including a brief "rational history" of our research work, and indicates how an architectural model can potentially facilitate the provision of self-managed adaptive software system.

  19. A scientific approach to writing for engineers and scientists

    CERN Document Server

    Berger, Robert E

    2014-01-01

    This book is a guide to technical writing, presented in a systematic framework that mirrors the logic associated with the scientific process itself. Other English books merely define concepts and provide rules; this one explains the reasoning behind the rules. Other writing books for scientists and engineers focus primarily on how to gather and organize materials; this one focuses primarily on how to compose a readable sentence. The approach should be satisfying not only to scientists and engineers, but also to anyone that once took a grammar course but can't remember the rules - because there was no exposure to underlying principles.

  20. Approaches to Software Engineering: A Human-Centred Perspective

    OpenAIRE

    Bannon, Liam J.

    2010-01-01

    International audience; The field of software engineering has been evolving since its inception in 1968. Arguments as to the exact nature of the field, whether it should be conceived as a real engineering profession, the role of formal methods, whether it is as much an art as a science, etc., continue to divide both practitioners and academics. My purpose here is not to debate these particular topics, but rather to approach the field from the outside, coming as I do from a long period of invo...

  1. The Impact of Agile Approach on Software Engineering Teams

    Directory of Open Access Journals (Sweden)

    Mazni Omar

    2011-01-01

    Full Text Available Problem statement: This study presents the initial findings on the impact of agile approach amongst Software Engineering (SE teams in one computer center in Malaysia. This study revealed that agile approach able to receive positive feedbacks and increase positive affectivity amongst team members during software development projects. Approach: This study used action research approach. Data were collected from four Software Engineering (SE teams who volunteered to participate in this study through a series of interviews, short-term observations and a questionnaire. Positive Affect scale from Positive Affect and Negative Affect Schedule (PANAS questionnaire was used to measure the developers’ state of positive affect during two intervals. Results: These findings found that not agile- XP practices adopted by the developers. This is due to knowledge barriers and organizational culture. However, agile approach induced level of positive affectivity amongst the members during software development process. In addition, agile approach promotes the members to be more active in coordinating and collaborating amongst teams. Conclusion: The findings in this study give an insight towards applying a flexible agile approach to accommodate and suit organizational culture. Effective methodology and organizational culture are important factors that must be considered to produce innovative teams and quality software.

  2. Merged ontology for engineering design: Contrasting empirical and theoretical approaches to develop engineering ontologies

    DEFF Research Database (Denmark)

    Ahmed, Saeema; Storga, M

    2009-01-01

    This paper presents a comparison of two previous and separate efforts to develop an ontology in the engineering design domain, together with an ontology proposal from which ontologies for a specific application may be derived. The research contrasts an empirical, user-centered approach to develop...

  3. NASA's Systems Engineering Approaches for Addressing Public Health Surveillance Requirements

    Science.gov (United States)

    Vann, Timi

    2003-01-01

    NASA's systems engineering has its heritage in space mission analysis and design, including the end-to-end approach to managing every facet of the extreme engineering required for successful space missions. NASA sensor technology, understanding of remote sensing, and knowledge of Earth system science, can be powerful new tools for improved disease surveillance and environmental public health tracking. NASA's systems engineering framework facilitates the match between facilitates the match between partner needs and decision support requirements in the areas of 1) Science/Data; 2) Technology; 3) Integration. Partnerships between NASA and other Federal agencies are diagrammed in this viewgraph presentation. NASA's role in these partnerships is to provide systemic and sustainable solutions that contribute to the measurable enhancement of a partner agency's disease surveillance efforts.

  4. Road Transport Congestion Costs Calculations-Adaptation to Engineering Approach

    Directory of Open Access Journals (Sweden)

    Marjan Lep

    2008-01-01

    Full Text Available The article represents so called “engineering” approach for computing the total road transport congestion costs. According to economic welfare theory, the total costs of transport congestion are defined as dead weight loss (DWL of infrastructure use. With a set of equations DWL could be formulated in a mathematical way. Because such form of equation is not directly applicable for concrete road network calculations it should be transformed into “engineering” form, which comprises transport engineering related data as classified road links, traffic volumes, passenger unit costs, etc. The equation is well applicable on the interurban road network; adaptations are needed for the urban road network cost calculations, where time losses are not so much related to the link travel time. The final equation was derived for the purposes of national road congestion cost calculation.

  5. Enhanced crystallizability by protein engineering approaches: a general overview.

    Science.gov (United States)

    Ruggiero, Alessia; Smaldone, Giovanni; Squeglia, Flavia; Berisio, Rita

    2012-07-01

    The limiting step in macromolecular crystallography is the preparation protein crystals suitable for X-ray diffraction studies. A strong prerequisite for the success of crystallization experiments is the ability to produce monodisperse and properly folded protein samples. Since the production of most protein is usually achieved using recombinant methods, it has become possible to engineer target proteins with increased propensities to form well diffracting crystals. Recent advances in bioinformatics, which takes advantage from an enhanced information in the protein databases, are of enormous help for the design of modified proteins. Based on bioinformatics analyses, the reduction of the structural complexity of proteins or their site-specific mutagenesis has proven to have a dramatic impact on both the yield of heterologous protein expression and its crystallizability. Therefore, protein engineering represents a valid tool which supports the classical crystallization screenings with a more rational approach. This review describes key methods of protein-engineering and provides a number of examples of their successful use in crystallization. Scope of proposed topic: This Topic is focused on state-of-art protein engineering techniques to increase the propensity of proteins to form crystals with suitable X-ray diffraction properties. Protein engineering methods have proven to be of great help for the crystallization of difficult targets. We herein review molecular biology and chemical methods to help protein crystallization.

  6. Flow-based approach for holistic factory engineering and design

    OpenAIRE

    Constantinescu, C.; Westkämper, E.

    2010-01-01

    The engineering of future factories requires digital tools along life cycle phases from investment planning to ramp-up. Manufacturers need scientific-based integrated highly dynamic data management systems for the participative and integrated factory planning. The paper presents a new approach for the continuously integrated product design, factory and process planning, through a service-oriented architecture for the implementation of digital factory tools. A first prototype of the digital fa...

  7. A process-based approach to engineering design knowledge reuse

    OpenAIRE

    Baxter, David

    2007-01-01

    Manufacturing enterprises are under increasing pressure to produce products of higher quality at lower cost in shorter time frames if they are to remain competitive. Engineering design support methods can help companies to achieve these goals. One such approach is design knowledge reuse. Industrial requirements have been identified as (i) the ability to rapidly create product variants; (ii) the ability to capture and re-use design knowledge, and; (iii) the capability to support...

  8. A Lean Approach to Scheduling Systems Engineering Resources

    Science.gov (United States)

    2013-05-01

    application in SE. We have defined a general Kanban -based Scheduling System (KSS) that we believe captures the essence of lean flow management visibility...finally delivered to the user Lean approaches strive to maximize flow through a process— often by using on-demand ( Kanban ) scheduling techniques...Technical Report,” Systems Engineering Research Center, SERC-2010-TR004, December 2009. 8. Anderson, David. (2010). Kanban : Successful Evolutionary

  9. A Predictive Approach to Network Reverse-Engineering

    Science.gov (United States)

    Wiggins, Chris

    2005-03-01

    A central challenge of systems biology is the ``reverse engineering" of transcriptional networks: inferring which genes exert regulatory control over which other genes. Attempting such inference at the genomic scale has only recently become feasible, via data-intensive biological innovations such as DNA microrrays (``DNA chips") and the sequencing of whole genomes. In this talk we present a predictive approach to network reverse-engineering, in which we integrate DNA chip data and sequence data to build a model of the transcriptional network of the yeast S. cerevisiae capable of predicting the response of genes in unseen experiments. The technique can also be used to extract ``motifs,'' sequence elements which act as binding sites for regulatory proteins. We validate by a number of approaches and present comparison of theoretical prediction vs. experimental data, along with biological interpretations of the resulting model. En route, we will illustrate some basic notions in statistical learning theory (fitting vs. over-fitting; cross- validation; assessing statistical significance), highlighting ways in which physicists can make a unique contribution in data- driven approaches to reverse engineering.

  10. Engineering

    National Research Council Canada - National Science Library

    Includes papers in the following fields: Aerospace Engineering, Agricultural Engineering, Chemical Engineering, Civil Engineering, Electrical Engineering, Environmental Engineering, Industrial Engineering, Materials Engineering, Mechanical...

  11. Efficient Graph Based Approach to Large Scale Role Engineering

    Directory of Open Access Journals (Sweden)

    Dana Zhang

    2014-04-01

    Full Text Available Role engineering is the process of defining a set of roles that offer administrative benefit for Role Based Access Control (RBAC, which ensures data privacy. It is a business critical task that is required by enterprises wishing to migrate to RBAC. However, existing methods of role generation have not analysed what constitutes a beneficial role and as a result, often produce inadequate solutions in a time consuming manner. To address the urgent issue of identifying high quality RBAC structures in real enterprise environments, we present a cost based analysis of the problem for both flat and hierarchical RBAC structures. Specifically we propose two cost models to evaluate the administration cost of roles and provide a k-partite graph approach to role engineering. Existing role cost evaulations are approximations that overestimate the benefit of a role. Our method and cost models can provide exact role cost and show when existing role cost evaluations can be used as a lower bound to improve efficiency without effecting quality of results. In the first work to address role engineering using large scale real data sets, we propose RoleAnnealing, a fast solution space search algorithm with incremental computation and guided search space heuristics. Our experimental results on both real and synthetic data sets demonstrate that high quality RBAC configurations that maintain data privacy are identified efficiently by RoleAnnealing. Comparison with an existing approach shows RoleAnnealing is significantly faster and produces RBAC configurations with lower cost.

  12. Approaches to Low Fuel Regression Rate in Hybrid Rocket Engines

    Directory of Open Access Journals (Sweden)

    Dario Pastrone

    2012-01-01

    Full Text Available Hybrid rocket engines are promising propulsion systems which present appealing features such as safety, low cost, and environmental friendliness. On the other hand, certain issues hamper the development hoped for. The present paper discusses approaches addressing improvements to one of the most important among these issues: low fuel regression rate. To highlight the consequence of such an issue and to better understand the concepts proposed, fundamentals are summarized. Two approaches are presented (multiport grain and high mixture ratio which aim at reducing negative effects without enhancing regression rate. Furthermore, fuel material changes and nonconventional geometries of grain and/or injector are presented as methods to increase fuel regression rate. Although most of these approaches are still at the laboratory or concept scale, many of them are promising.

  13. An engineering based approach for hydraulic computations in river flows

    Science.gov (United States)

    Di Francesco, S.; Biscarini, C.; Pierleoni, A.; Manciola, P.

    2016-06-01

    This paper presents an engineering based approach for hydraulic risk evaluation. The aim of the research is to identify a criteria for the choice of the simplest and appropriate model to use in different scenarios varying the characteristics of main river channel. The complete flow field, generally expressed in terms of pressure, velocities, accelerations can be described through a three dimensional approach that consider all the flow properties varying in all directions. In many practical applications for river flow studies, however, the greatest changes occur only in two dimensions or even only in one. In these cases the use of simplified approaches can lead to accurate results, with easy to build and faster simulations. The study has been conducted taking in account a dimensionless parameter of channels (ratio of curvature radius and width of the channel (R/B).

  14. A new approach to heart valve tissue engineering

    DEFF Research Database (Denmark)

    Kaasi, Andreas; Cestari, Idágene A.; Stolf, Noedir A G.

    2011-01-01

    The 'biomimetic' approach to tissue engineering usually involves the use of a bioreactor mimicking physiological parameters whilst supplying nutrients to the developing tissue. Here we present a new heart valve bioreactor, having as its centrepiece a ventricular assist device (VAD), which exposes...... chamber. Subsequently, applied vacuum to the pneumatic chamber causes the blood chamber to fill. A mechanical heart valve was placed in the VAD's inflow position. The tissue engineered (TE) valve was placed in the outflow position. The VAD was coupled in series with a Windkessel compliance chamber......, variable throttle and reservoir, connected by silicone tubings. The reservoir sat on an elevated platform, allowing adjustment of ventricular preload between 0 and 11 mmHg. To allow for sterile gaseous exchange between the circuit interior and exterior, a 0.2 µm filter was placed at the reservoir. Pressure...

  15. A software architecture centric engineering approach for Internetware

    Institute of Scientific and Technical Information of China (English)

    MEI Hong; HUANG Gang; ZHAO Haiyan; JIAO Wenpin

    2006-01-01

    As a new software paradigm evolved by the Internet, Internetware brings many challenges for the traditional software development methods and techniques. Though architecture-based component composition (ABC) approach is originated in the traditional software paradigm, it supports the engineering of Internetware effectively due to its philosophy, rationales and mechanisms. ABC has three major contributions to the engineering of Internetware in detail. First, the feature oriented domain modeling method can structure the "disordered" "software entities" to "ordered Internetware" bottom-up in the problem space. Second, the architecture centric design and analysis method can support the development of self-adaptive Internetware. Third, the component operating platform is a reflective and self-adaptive middleware that not only provides Internetware with a powerful and flexible runtime infrastructure but also enables the self-adaptation of the structure and individual entities of Internetware.

  16. Multi-hazard approaches to civil infrastructure engineering

    CERN Document Server

    LaFave, James

    2016-01-01

    This collection focuses on the development of novel approaches to address one of the most pressing challenges of civil engineering, namely the mitigation of natural hazards. Numerous engineering books to date have focused on, and illustrate considerable progress toward, mitigation of individual hazards (earthquakes, wind, and so forth.). The current volume addresses concerns related to overall safety, sustainability and resilience of the built environment when subject to multiple hazards: natural disaster events that are concurrent and either correlated (e.g., wind and surge); uncorrelated (e.g., earthquake and flood); cascading (e.g., fire following earthquake); or uncorrelated and occurring at different times (e.g., wind and earthquake). The authors examine a range of specific topics including methodologies for vulnerability assessment of structures, new techniques to reduce the system demands through control systems; instrumentation, monitoring and condition assessment of structures and foundations; new te...

  17. An Event-driven, Value-based, Pull Systems Engineering Scheduling Approach

    Science.gov (United States)

    2012-03-01

    combining a services approach to systems engineering with a kanban -based scheduling system. It provides the basis for validating the approach with...agent-based simulations. Keywords-systems engineering; systems engineering process; lean; kanban ; process simulation I. INTRODUCTION AND BACKGROUND...approaches [8], [9], we are investigating the use of flow-based pull scheduling techniques ( kanban systems) in a rapid response development

  18. Engineered Micro-Objects as Scaffolding Elements in Cellular Building Blocks for Bottom-Up Tissue Engineering Approaches

    NARCIS (Netherlands)

    Leferink, A.M.; Schipper, D.; Arts, E.; Vrij, E.J.; Rivron, N.C.; Karperien, H.B.J.; Mittmann, K.; Blitterswijk, van C.A.; Moroni, L.; Truckenmuller, R.K.

    2014-01-01

    A material-based bottom-up approach is proposed towards an assembly of cells and engineered micro-objects at the macroscale. We show how shape, size and wettability of engineered micro-objects play an important role in the behavior of cells on these objects. This approach can, among other applicatio

  19. Sustainable solid waste management a systems engineering approach

    CERN Document Server

    Chang, N

    2015-01-01

    Interactions between human activities and the environment are complicated and often difficult to quantify. In many occasions, judging where the optimal balance should lie among environmental protection, social well-being, economic growth, and technological progress is complex. The use of a systems engineering approach will fill in the gap contributing to how we understand the intricacy by a holistic way and how we generate better sustainable solid waste management practices. This book aims to advance interdisciplinary understanding of intertwined facets between policy and technology relevant to solid waste management issues interrelated to climate change, land use, economic growth, environmental pollution, industrial ecology, and population dynamics.

  20. TEPCO's Approach to Power-Engineer Human Resource Development

    Science.gov (United States)

    Sato, Masaki

    We think 'human resources and technology' is developed only by self-training continuously, keeping higher motivation and practicing repeatedly. Moreover it is indispensable for sustainable development of company. Management vision, top-down message with vertical communication, and bottom-up systematic approaches are necessary for sustainable human resource development, sharing the value with coordination, and in addition, OJT and Off-JT method should be used effectively. This paper shows TEPCO's attempts to develop engineers' technical skills as a reference of a in-company continuing professional development.

  1. Energy systems a new approach to engineering thermodynamics

    CERN Document Server

    Gicquel, Renaud

    2011-01-01

    Forewords, About the Author, General introduction, Structure of the book, Objectives, A working tool on many levels, Mind Maps, List of Symbols, Conversion FactorsI First Steps in Engineering Thermodynamics1 A New Educational Paradigm1.1 Introduction1.2 General remarks on the evolution of training specifi cations1.3 Specifi cs of applied thermodynamics teaching1.4 A new educational paradigm1.5 Diapason modules1.6 A three-step progressive approach1.7 Main pedagogic innovations brought by Thermoptim1.8 Digital resources of the Thermoptim-UNIT portal1.9 Comparison with other tools with teaching p

  2. Esophageal tissue engineering: A new approach for esophageal replacement

    Institute of Scientific and Technical Information of China (English)

    Giorgia Totonelli; Panagiotis Maghsoudlou; Jonathan M Fishman; Giuseppe Orlando; Tahera Ansari; Paul Sibbons; Martin A Birchall

    2012-01-01

    A number of congenital and acquired disorders require esophageal tissue replacement.Various surgical techniques,such as gastric and colonic interposition,are standards of treatment,but frequently complicated by stenosis and other problems.Regenerative medicine approaches facilitate the use of biological constructs to replace or regenerate normal tissue function.We review the literature of esophageal tissue engineering,discuss its implications,compare the methodologies that have been employed and suggest possible directions for the future.Medline,Embase,the Cochrane Library,National Research Register and ClinicalTrials.gov databases were searched with the following search terms:stem cell and esophagus,esophageal replacement,esophageal tissue engineering,esophageal substitution.Reference lists of papers identified were also examined and experts in this field contacted for further information.All full-text articles in English of all potentially relevant abstracts were reviewed.Tissue engineering has involved acellular scaffolds that were either transplanted with the aim of being repopulated by host cells or seeded prior to transplantation.When acellular scaffolds were used to replace patch and short tubular defects they allowed epithelial and partial muscular migration whereas when employed for long tubular defects the results were poor leading to an increased rate of stenosis and mortality.Stenting has been shown as an effective means to reduce stenotic changes and promote cell migration,whilst omental wrapping to induce vascularization of the construct has an uncertain benefit.Decellularized matrices have been recently suggested as the optimal choice for scaffolds,but smart polymers that will incorporate signalling to promote cell-scaffold interaction may provide a more reproducible and available solution.Results in animal models that have used seeded scaffolds strongly suggest that seeding of both muscle and epithelial cells on scaffolds prior to implantation is a

  3. Molecular basis of glyphosate resistance: Different approaches through protein engineering

    Science.gov (United States)

    Pollegioni, Loredano; Schonbrunn, Ernst; Siehl, Daniel

    2011-01-01

    Glyphosate (N-phosphonomethyl-glycine) is the most-used herbicide in the world: glyphosate-based formulations exhibit broad-spectrum herbicidal activity with minimal human and environmental toxicity. The extraordinary success of this simple small molecule is mainly due to the high specificity of glyphosate towards the plant enzyme enolpyruvylshikimate-3-phosphate synthase in the shikimate pathway leading to biosynthesis of aromatic amino acids. Starting in 1996, transgenic glyphosate-resistant plants were introduced thus allowing the application of the herbicide to the crop (post-emergence) to remove emerged weeds without crop damage. This review focuses on the evolution of mechanisms of resistance to glyphosate as obtained through natural diversity, the gene shuffling approach to molecular evolution, and a rational, structure-based approach to protein engineering. In addition, we offer rationale for the means by which the modifications made have had their intended effect. PMID:21668647

  4. Information management in software engineering: A hypertext based approach

    Energy Technology Data Exchange (ETDEWEB)

    Garg, P.K.

    1989-01-01

    Large scale software systems requires automated support for the communication and coordination of cooperative effort required to manage, create, store, print, and use large volumes of information. Hypertext is a flexible, general purpose, non-linear model for storing textual information. The thesis of this dissertation is that software engineering information should be managed using a hypertext based approach. Previous models of software engineering information do not provide the flexibility and generality of a hypertext model. We describe the design and implementation of an Intelligent Software Hypertext System (Ishys), for management of software engineering information. In Ishys, Basic Templates (BTs) are nodes of a hypertext, which can have point-to-point and node-to-node links. Forms are sequences of BTs which can be used to model software life cycle documents. Compositions are arbitrary collections of BTs. Projects represent partitions of the hypertext such that each project has the same forms. Tasks are responsibilities of agents which use or produce forms. Tasks are composed of actions which use or produce BTs. Actions are composed of primitive actions which are commands provided through Ishys. In a general user mode, users create information in Ishys by instantiating BTs. In a super user mode, users define the projects, forms, BTs, tasks, actions, and primitive actions. Structured communication about BTs is supported through annotations attached to different points within BTs. To illustrate the flexibility and generality of the hypertext based approach we show how a hypertext can support generalizations, specializations, revisions, and aggregations. To illustrate the power of hypertext systems in supporting collaborative work, we discuss how a hypertext system can support two models for composition of node composition: (1) the assembly line model, and (2) the exploratory assembly model.

  5. A new approach to grain boundary engineering for nanocrystalline materials

    Directory of Open Access Journals (Sweden)

    Shigeaki Kobayashi

    2016-11-01

    Full Text Available A new approach to grain boundary engineering (GBE for high performance nanocrystalline materials, especially those produced by electrodeposition and sputtering, is discussed on the basis of some important findings from recently available results on GBE for nanocrystalline materials. In order to optimize their utility, the beneficial effects of grain boundary microstructures have been seriously considered according to the almost established approach to GBE. This approach has been increasingly recognized for the development of high performance nanocrystalline materials with an extremely high density of grain boundaries and triple junctions. The effectiveness of precisely controlled grain boundary microstructures (quantitatively characterized by the grain boundary character distribution (GBCD and grain boundary connectivity associated with triple junctions has been revealed for recent achievements in the enhancement of grain boundary strengthening, hardness, and the control of segregation-induced intergranular brittleness and intergranular fatigue fracture in electrodeposited nickel and nickel alloys with initial submicrometer-grained structure. A new approach to GBE based on fractal analysis of grain boundary connectivity is proposed to produce high performance nanocrystalline or submicrometer-grained materials with desirable mechanical properties such as enhanced fracture resistance. Finally, the potential power of GBE is demonstrated for high performance functional materials like gold thin films through precise control of electrical resistance based on the fractal analysis of the grain boundary microstructure.

  6. A new approach to grain boundary engineering for nanocrystalline materials.

    Science.gov (United States)

    Kobayashi, Shigeaki; Tsurekawa, Sadahiro; Watanabe, Tadao

    2016-01-01

    A new approach to grain boundary engineering (GBE) for high performance nanocrystalline materials, especially those produced by electrodeposition and sputtering, is discussed on the basis of some important findings from recently available results on GBE for nanocrystalline materials. In order to optimize their utility, the beneficial effects of grain boundary microstructures have been seriously considered according to the almost established approach to GBE. This approach has been increasingly recognized for the development of high performance nanocrystalline materials with an extremely high density of grain boundaries and triple junctions. The effectiveness of precisely controlled grain boundary microstructures (quantitatively characterized by the grain boundary character distribution (GBCD) and grain boundary connectivity associated with triple junctions) has been revealed for recent achievements in the enhancement of grain boundary strengthening, hardness, and the control of segregation-induced intergranular brittleness and intergranular fatigue fracture in electrodeposited nickel and nickel alloys with initial submicrometer-grained structure. A new approach to GBE based on fractal analysis of grain boundary connectivity is proposed to produce high performance nanocrystalline or submicrometer-grained materials with desirable mechanical properties such as enhanced fracture resistance. Finally, the potential power of GBE is demonstrated for high performance functional materials like gold thin films through precise control of electrical resistance based on the fractal analysis of the grain boundary microstructure.

  7. Engineering nanomaterials with a combined electrochemical and molecular biomimetic approach

    Science.gov (United States)

    Dai, Haixia

    Biocomposite materials, such as bones, teeth, and shells, are created using mild aqueous solution-based processes near room temperature. Proteins add flexibility to these processes by facilitating the nucleation, growth, and ordering of specific inorganic materials into hierarchical structures. We aim to develop a biomimetic strategy for engineering technologically relevant inorganic materials with controlled compositions and structures, as Nature does, using proteins to orchestrate material formation and assembly. This approach involves three basic steps: (i) preparation of inorganic substrates compatible with combinatorial polypeptide screening; (ii) identification of inorganic-binding polypeptides and their engineering into inorganic-binding proteins; and (iii) protein-mediated inorganic nucleation and organization. Cuprous oxide (Cu2O), a p-type semiconductor, has been used to demonstrate all three steps. Zinc oxide (ZnO), an n-type semiconductor, has been used to show the generality of selected steps. Step (i), preparation of high quality inorganic substrates to select inorganic-binding polypeptides, was accomplished using electrochemical microfabrication to grow and pattern Cu2O and ZnO. Raman spectroscopy and x-ray photoelectron spectroscopy were used to verify phase purity and compositional stability of these surfaces during polypeptide screening. Step (ii), accomplished in collaboration with personnel in Prof Baneyx' lab at the University of Washington, involved incubating the inorganic substrates with the FliTrx(TM) random peptide library to identify cysteine-constrained dodecapeptides that bind the targeted inorganic. Insertion of a Cu2O-binding dodecapeptide into the DNA-binding protein TraI endowed the engineered TraI with strong affinity for Cu2O (Kd ≈ 10 -8 M). Finally, step (iii) involved nonequilibrium synthesis and organization of Cu2O nanoparticles, taking advantage of the inorganic and DNA recognition properties of the engineered TraI. The

  8. An Integrated Approach for Strategic Development of Engineering Curricula: Focus on Students' Design Skills

    Science.gov (United States)

    Rehman, H.-u.; Said, R. A.; Al-assaf, Y.

    2009-01-01

    This paper proposes an integrated approach for developing the engineering curricula with a specific focus on engineering design. The proposed approach allows a continuous and coherent development of engineering students' design skills throughout the entire undergraduate curriculum. This ongoing design experience is delivered at an involvement and…

  9. An integrated systems engineering approach to aircraft design

    Science.gov (United States)

    Price, M.; Raghunathan, S.; Curran, R.

    2006-06-01

    The challenge in Aerospace Engineering, in the next two decades as set by Vision 2020, is to meet the targets of reduction of nitric oxide emission by 80%, carbon monoxide and carbon dioxide both by 50%, reduce noise by 50% and of course with reduced cost and improved safety. All this must be achieved with expected increase in capacity and demand. Such a challenge has to be in a background where the understanding of physics of flight has changed very little over the years and where industrial growth is driven primarily by cost rather than new technology. The way forward to meet the challenges is to introduce innovative technologies and develop an integrated, effective and efficient process for the life cycle design of aircraft, known as systems engineering (SE). SE is a holistic approach to a product that comprises several components. Customer specifications, conceptual design, risk analysis, functional analysis and architecture, physical architecture, design analysis and synthesis, and trade studies and optimisation, manufacturing, testing validation and verification, delivery, life cycle cost and management. Further, it involves interaction between traditional disciplines such as Aerodynamics, Structures and Flight Mechanics with people- and process-oriented disciplines such as Management, Manufacturing, and Technology Transfer. SE has become the state-of-the-art methodology for organising and managing aerospace production. However, like many well founded methodologies, it is more difficult to embody the core principles into formalised models and tools. The key contribution of the paper will be to review this formalisation and to present the very latest knowledge and technology that facilitates SE theory. Typically, research into SE provides a deeper understanding of the core principles and interactions, and helps one to appreciate the required technical architecture for fully exploiting it as a process, rather than a series of events. There are major issues as

  10. Generic Engineering Competencies: A Review and Modelling Approach

    Science.gov (United States)

    Male, Sally A.

    2010-01-01

    This paper puts forward the view that engineering educators have a responsibility to prepare graduates for engineering work and careers. The current literature reveals gaps between the competencies required for engineering work and those developed in engineering education. Generic competencies feature in these competency gaps. Literature suggests…

  11. Failure of Engineering Artifacts: A Life Cycle Approach

    NARCIS (Netherlands)

    Del Frate, L.

    2012-01-01

    Failure is a central notion both in ethics of engineering and in engineering practice. Engineers devote considerable resources to assure their products will not fail and considerable progress has been made in the development of tools and methods for understanding and avoiding failure. Engineering et

  12. Failure of Engineering Artifacts: A Life Cycle Approach

    NARCIS (Netherlands)

    Del Frate, L.

    2012-01-01

    Failure is a central notion both in ethics of engineering and in engineering practice. Engineers devote considerable resources to assure their products will not fail and considerable progress has been made in the development of tools and methods for understanding and avoiding failure. Engineering

  13. A Design Approach for Collaboration Processes: A Multi-Method Design Science Study in Collaboration Engineering

    NARCIS (Netherlands)

    Kolfschoten, G.L.; De Vreede, G.J.

    2009-01-01

    Collaboration Engineering is an approach for the design and deployment of repeatable collaboration processes that can be executed by practitioners without the support of collaboration professionals such as facilitators. A critical challenge in Collaboration Engineering concerns how the design activi

  14. A Systems Engineering Approach to Quality Assurance for Aerospace Testing

    Science.gov (United States)

    Shepherd, Christena C.

    2015-01-01

    On the surface, it appears that AS91001 has little to say about how to apply a Quality Management System (QMS) to major aerospace test programs (or even smaller ones). It also appears that there is little in the quality engineering Body of Knowledge (BOK)2 that applies to testing, unless it is nondestructive examination (NDE), or some type of lab or bench testing associated with the manufacturing process. However, if one examines: a) how the systems engineering (SE) processes are implemented throughout a test program; and b) how these SE processes can be mapped to the requirements of AS9100, a number of areas for involvement of the quality professional are revealed. What often happens is that quality assurance during a test program is limited to inspections of the test article; what could be considered a manufacturing al fresco approach. This limits the quality professional and is a disservice to the programs and projects, since there are a number of ways that quality can enhance critical processes, and support efforts to improve risk reduction, efficiency and effectiveness.

  15. Design Approach for Spiral Milling Parts Using Knowledge Based Engineering

    Science.gov (United States)

    Humpa, M.; Köhler, P.

    2014-07-01

    From the engineering point of view there are still problems regarding geometry modelling that cannot be satisfactorily solved despite efficient CAD systems. This applies in particular to virtual models when they are meant to match with the resulting manufacturing geometry of components as closely as possible. In this paper, relationships between modelling and manufacturing strategies are discussed. The focus is directed to the relationship between the modelling strategy and the manufacturing process by spiral milling with a ball cutter, whereby especially the influence of the tool geometry and the tool paths for the modelling strategy will be investigated. By means of an appropriate example of a design of spiral mandrel die from the field of plastics processing an approach will show how functional design and manufacturing-oriented design can be coupled and automated.

  16. A new mathematical approach to the Stirling engine analysis

    Science.gov (United States)

    de Cicco, A.

    A new approach to the theoretical analysis of Stirling machine is presented. The mathematical model takes into account the phenomena occurring into the all main parts of the engine such as the expansion space, the heater, the regenerator, the cooler and the compression space as well. Energy, mass and momentum conservation differential equations are applied to each control volume, with the assumption the working fluid being regarded as a perfect, compressible gas, while the flow is unsteady, one dimensional, with friction and heat transfer. A set of algebraic equations is introduced, in order to consider the boundary conditions which express the constancy of total enthalpy and mass flow, and total pressure drop of the fluid flowing through the boundary sections of the control volumes.

  17. Between Deep and Surface: Procedural Approaches to Learning in Engineering Education Contexts

    Science.gov (United States)

    Case, Jennifer; Marshall, Delia

    2004-01-01

    This article describes two approaches to learning (in addition to the classic deep and surface approaches) identified in studies of student learning in engineering contexts. The first study identified the 'procedural deep' approach in a group of engineering foundation programme students in the UK, while the second study identified the 'procedural…

  18. Seeds of Solutions(TM): An economical & efficient approach towards power engineering education

    Science.gov (United States)

    Alvarez, Eli

    Power demands are set to increase over the next twenty years; however, research shows that there may be a shortage of power engineers due to an appreciable percentage of the current power engineer workforce retiring, insufficient enrollment in power engineering programs and a lack of emphasis in power engineering at the university level. This thesis provides supporting research for future power demands, workforce and faculty shortages. Using temporary research in modern learning / teaching styles, student / teacher perceptions, educational trends and regional course offerings, this thesis describes a learning approach towards power engineering education. Designed specifically for universities with little to no power engineering course offerings and universities that wish to augment their existing approach, the approach incorporates an emphasis in fundamentals and engineering design making it economical and easy to implement. This thesis also includes three (3) video laboratory examples incorporating all elements of the approach.

  19. Object-oriented re-engineering: a comprehensive approach

    OpenAIRE

    Signore, Oreste; Loffredo, Mario

    1993-01-01

    Software re-engineering and object orientation are two areas of growing interest in the last years. However, while many researchers have focused their interest in the object-oriented design methodologies, a little attention has been paid to the re-engineering towards an object-oriented environment. In this paper, after a brief discussion of the re-engineering issues, we examine the motivations towards object-oriented re-engineering (extendibility, robustness and reusability of the code) and t...

  20. Band gap engineering via doping: A predictive approach

    Energy Technology Data Exchange (ETDEWEB)

    Andriotis, Antonis N., E-mail: andriot@iesl.forth.gr [Institute of Electronic Structure and Laser, FORTH, P.O. Box 1527, 71110 Heraklio, Crete (Greece); Menon, Madhu, E-mail: super250@uky.edu [Department of Physics and Astronomy and Center for Computational Sciences, University of Kentucky, Lexington, Kentucky 40506 (United States)

    2015-03-28

    We employ an extension of Harrison's theory at the tight binding level of approximation to develop a predictive approach for band gap engineering involving isovalent doping of wide band gap semiconductors. Our results indicate that reasonably accurate predictions can be achieved at qualitative as well as quantitative levels. The predictive results were checked against ab initio ones obtained at the level of DFT/SGGA + U approximation. The minor disagreements between predicted and ab initio results can be attributed to the electronic processes not incorporated in Harrison's theory. These include processes such as the conduction band anticrossing [Shan et al., Phys. Rev. Lett. 82, 1221 (1999); Walukiewicz et al., Phys. Rev. Lett. 85, 1552 (2000)] and valence band anticrossing [Alberi et al., Phys. Rev. B 77, 073202 (2008); Appl. Phys. Lett. 92, 162105 (2008); Appl. Phys. Lett. 91, 051909 (2007); Phys. Rev. B 75, 045203 (2007)], as well as the multiorbital rehybridization. Another cause of disagreement between the results of our predictive approach and the ab initio ones is shown to be the result of the shift of Fermi energy within the impurity band formed at the edge of the valence band maximum due to rehybridization. The validity of our approach is demonstrated with example applications for the systems GaN{sub 1−x}Sb{sub x}, GaP{sub 1−x}Sb{sub x}, AlSb{sub 1−x}P{sub x}, AlP{sub 1−x}Sb{sub x}, and InP{sub 1−x}Sb{sub x}.

  1. The catchment based approach using catchment system engineering

    Science.gov (United States)

    Jonczyk, Jennine; Quinn, Paul; Barber, Nicholas; Wilkinson, Mark

    2015-04-01

    The catchment based approach (CaBa) has been championed as a potential mechanism for delivery of environmental directives such as the Water Framework Directive in the UK. However, since its launch in 2013, there has been only limited progress towards achieving sustainable, holistic management, with only a few of examples of good practice ( e.g. from the Tyne Rivers trust). Common issues with developing catchment plans over a national scale include limited data and resources to identify issues and source of those issues, how to systematically identify suitable locations for measures or suites of measures that will have the biggest downstream impact and how to overcome barriers for implementing solutions. Catchment System Engineering (CSE) is an interventionist approach to altering the catchment scale runoff regime through the manipulation of hydrological flow pathways throughout the catchment. A significant component of the runoff generation can be managed by targeting hydrological flow pathways at source, such as overland flow, field drain and ditch function, greatly reducing erosive soil losses. Coupled with management of farm nutrients at source, many runoff attenuation features or measures can be co-located to achieve benefits for water quality and biodiversity. A catchment, community-led mitigation measures plan using the CSE approach will be presented from a catchment in Northumberland, Northern England that demonstrate a generic framework for identification of multi-purpose features that slow, store and filter runoff at strategic locations in the landscape. Measures include within-field barriers, edge of field traps and within-ditch measures. Progress on the implementation of measures will be reported alongside potential impacts on the runoff regime at both local and catchment scale and costs.

  2. A Systems Engineering Approach to Electro-Mechanical Actuator Diagnostic and Prognostic Development

    Data.gov (United States)

    National Aeronautics and Space Administration — The authors have formulated a Comprehensive Systems Engineering approach to Electro-Mechanical Actuator (EMA) Prognostics and Health Management (PHM) system...

  3. A NEW REVERSE ENGINEERING APPROACH TO CONVERT FORM FILL FORMAT DOCUMENT INTO UML CLASS DIAGRAM

    Directory of Open Access Journals (Sweden)

    Mohammad I. Muhairat

    2014-12-01

    Full Text Available This paper propose a new reverse engineering approach to convert a form fill format document into a set of related tables that can be used to generate the entity relationship diagram. A relationship between the set of tables is generated. In addition, the entity relationship diagram will be converted into a UML class diagram. However, this approach will be very helpful for researchers and practitioners in Software Engineering field, since most of the reverse engineering approaches are based on source code. This approach is tested by using several word form fill format documents and the results show a high accuracy rates comparing with the forward engineering.

  4. Multidisciplinary and Active/Collaborative Approaches in Teaching Requirements Engineering

    Science.gov (United States)

    Rosca, Daniela

    2005-01-01

    The requirements engineering course is a core component of the curriculum for the Master's in Software Engineering programme, at Monmouth University (MU). It covers the process, methods and tools specific to this area, together with the corresponding software quality issues. The need to produce software engineers with strong teamwork and…

  5. Multidisciplinary and Active/Collaborative Approaches in Teaching Requirements Engineering

    Science.gov (United States)

    Rosca, Daniela

    2005-01-01

    The requirements engineering course is a core component of the curriculum for the Master's in Software Engineering programme, at Monmouth University (MU). It covers the process, methods and tools specific to this area, together with the corresponding software quality issues. The need to produce software engineers with strong teamwork and…

  6. A Novel Approach to Physiology Education for Biomedical Engineering Students

    Science.gov (United States)

    DiCecco, J.; Wu, J.; Kuwasawa, K.; Sun, Y.

    2007-01-01

    It is challenging for biomedical engineering programs to incorporate an indepth study of the systemic interdependence of cells, tissues, and organs into the rigorous mathematical curriculum that is the cornerstone of engineering education. To be sure, many biomedical engineering programs require their students to enroll in anatomy and physiology…

  7. Sustainable Development in Engineering Education: A Pedagogical Approach

    Science.gov (United States)

    Ahrens, A.; Zascerinska, J.

    2012-01-01

    Engineering education is facing a challenge of the development of student engineers' social responsibility in the context of sustainable development. The aim of the research is to analyze efficiency of engineering curriculum in the context of sustainable development underpinning elaboration of pedagogical guidelines on the development of students'…

  8. The engineering of artificial cellular nanosystems using synthetic biology approaches.

    Science.gov (United States)

    Wu, Fan; Tan, Cheemeng

    2014-01-01

    Artificial cellular systems are minimal systems that mimic certain properties of natural cells, including signaling pathways, membranes, and metabolic pathways. These artificial cells (or protocells) can be constructed following a synthetic biology approach by assembling biomembranes, synthetic gene circuits, and cell-free expression systems. As artificial cells are built from bottom-up using minimal and a defined number of components, they are more amenable to predictive mathematical modeling and engineered controls when compared with natural cells. Indeed, artificial cells have been implemented as drug delivery machineries and in situ protein expression systems. Furthermore, artificial cells have been used as biomimetic systems to unveil new insights into functions of natural cells, which are otherwise difficult to investigate owing to their inherent complexity. It is our vision that the development of artificial cells would bring forth parallel advancements in synthetic biology, cell-free systems, and in vitro systems biology. For further resources related to this article, please visit the WIREs website. Conflict of interests: The authors declare that they have no competing financial interests. © 2014 Wiley Periodicals, Inc.

  9. Reservoir geomechanics: new approach to reservoir engineering analysis

    Energy Technology Data Exchange (ETDEWEB)

    Settari, A.; Walters, D.A.; Behie, G.A. [Duke Engineering and Services Inc., Calgary, AB (Canada)

    1999-07-01

    The rock mechanics aspects of reservoir behavior are reviewed, and a description is included of some recent trends in coupled reservoir and strata mechanics modelling. Case histories are summarized which are field applications of these new trends and tools. These case histories include: (1) high rate injection into an oil sand reservoir; (2) compaction modelling of a North Sea reservoir; and (3) brine disposal at a fracturing pressure. Coupled geomechanical modelling is feasible on a full field scale, and it provides flexibility in the degree of coupling and calculational efficiency. The scope of interest in data gathering and characterization must be extended beyond reservoir boundaries because of the coupled modelling approach. This modelling provides results that can be employed in integrated reservoir management that includes reservoir engineering, drilling and completions. Considering the three case histories, coupled modelling can be used for predicting fracture initiation and re-orientation, reservoir compaction and deformations, and enhancement of injectivity due to stress dependent formation properties. Coupled modelling has brought reservoir modelling to a new realistic level and produces significant economic gains. 15 refs., 8 figs.

  10. A TOTAL QUALITY MANAGEMENT APPROACH TO CIVIL ENGINEERING CONSULTING

    Directory of Open Access Journals (Sweden)

    G.A.L. Ambrose

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: The article describes the development of a framework for the implementation of a Total Quality Management (TQM approach in the civil consulting industry through the five phases of the typical civil engineering project. For any project to be successful the project team members must take collective and individual responsibility for their role in the project implementation. The organisational goal is “to make money now and in the future”. To achieve this goal the organization must provide value to its clientele. The clients are searching for the silver bullet; double the performance at half the price. TQM provides a means to achieve this goal.

    AFRIKAANSE OPSOMMING: Die artikel beskryf die ontwikkeling van 'n raamwerk vir die implementering van 'n gehaltebestuurstelsel vir die siviele raadgewende bedryf soos dit deelneem aan die vyf fases van 'n tipiese siviele ingenieursprojek. Vir die suksesvolle afhandeling van 'n projek is dit noodsaaklik dat alle projekspanlede gesamentlik en afsonderlik verantwoordelikheid moet aanvaar vir hulle eie betrokkenheid by die projekimplementering. Die organisasie se oogmerk is om “nou en in die toekoms geld te maak”. Ten einde hierdie oogmerk te bereik moet die organisasie waarde vir sy kliënte bied. 'n Gehaltebestuurstelsel voorsien die gereedskap om hierdie doelwit te bereik.

  11. Systems approach to managing educational quality in the engineering classroom

    Science.gov (United States)

    Grygoryev, Kostyantyn

    Today's competitive environment in post-secondary education requires universities to demonstrate the quality of their programs in order to attract financing, and student and academic talent. Despite significant efforts devoted to improving the quality of higher education, systematic, continuous performance measurement and management still have not reached the level where educational outputs and outcomes are actually produced---the classroom. An engineering classroom is a complex environment in which educational inputs are transformed by educational processes into educational outputs and outcomes. By treating a classroom as a system, one can apply tools such as Structural Equation Modeling, Statistical Process Control, and System Dynamics in order to discover cause-and-effect relationships among the classroom variables, control the classroom processes, and evaluate the effect of changes to the course organization, content, and delivery, on educational processes and outcomes. Quality improvement is best achieved through the continuous, systematic application of efforts and resources. Improving classroom processes and outcomes is an iterative process that starts with identifying opportunities for improvement, designing the action plan, implementing the changes, and evaluating their effects. Once the desired objectives are achieved, the quality improvement cycle may start again. The goal of this research was to improve the educational processes and outcomes in an undergraduate engineering management course taught at the University of Alberta. The author was involved with the course, first, as a teaching assistant, and, then, as a primary instructor. The data collected from the course over four years were used to create, first, a static and, then, a dynamic model of a classroom system. By using model output and qualitative feedback from students, changes to the course organization and content were introduced. These changes led to a lower perceived course workload and

  12. An Alternative Educational Approach for an Inorganic Chemistry Laboratory Course in Industrial and Chemical Engineering

    Science.gov (United States)

    Garces, Andres; Sanchez-Barba, Luis Fernando

    2011-01-01

    We describe an alternative educational approach for an inorganic chemistry laboratory module named "Experimentation in Chemistry", which is included in Industrial Engineering and Chemical Engineering courses. The main aims of the new approach were to reduce the high levels of failure and dropout on the module and to make the content match the…

  13. An Alternative Educational Approach for an Inorganic Chemistry Laboratory Course in Industrial and Chemical Engineering

    Science.gov (United States)

    Garces, Andres; Sanchez-Barba, Luis Fernando

    2011-01-01

    We describe an alternative educational approach for an inorganic chemistry laboratory module named "Experimentation in Chemistry", which is included in Industrial Engineering and Chemical Engineering courses. The main aims of the new approach were to reduce the high levels of failure and dropout on the module and to make the content match the…

  14. "Bridging" Engineering & Art: An Outreach Approach for Middle and High School Students

    Science.gov (United States)

    Asiabanpour, Bahram; DesChamps-Benke, Nicole; Wilson, Thomas; Loerwald, Matthew; Gourgey, Hannah

    2010-01-01

    This paper describes a novel outreach approach to high school and middle school students to familiarize them with engineering functions and methods. In this approach students participated in a seven-day summer research camp and learned many engineering skills and tools such as CAD solid modeling, finite element analysis, rapid prototyping,…

  15. An Integrated Approach to Recruiting and Retaining Appalachian Engineering Students

    Science.gov (United States)

    Winn, Gary; Hensel, Robin; Curtis, Reagan; Taylor, Lydotta M.; Cilento, Gene

    2012-01-01

    Recruiting and retaining Appalachian engineering students is difficult for a variety of ecological and cultural reasons. At West Virginia University an NSF STEP grant has allowed the development of specific interventions to evolve from an ecological model we describe here. The interventions include web-based, realistic engineering design exercises…

  16. Ramjets: Thermal management – An integrated engineering approach

    NARCIS (Netherlands)

    Veraar, R.G.

    2010-01-01

    Within the framework of the VKI/RTO Lecture Series on ‘High Speed Propulsion: Engine Design – Integration and Thermal Management’, this lecture focuses on thermal management of ramjet propulsion systems. This is done by describing an engineering model that can be used to perform an integrated therma

  17. Translational Approaches in Tissue Engineering and Regenerative Medicine

    CERN Document Server

    Mao, Jeremy J

    2007-01-01

    This landmark book identifies the current and forthcoming roadblocks to scientific research and technological development in stem cell research, tissue engineering, wound healing, and in-vivo animal models. The book is the first to focus on the translational aspect of tissue engineering and regenerative medicine and bridges the gap between laboratory discovery and clinical applications.

  18. An Industrial Engineering Approach to Cost Containment of Pharmacy Education.

    Science.gov (United States)

    Duncan, Wendy; Bottenberg, Michelle; Chase, Marilea; Chesnut, Renae; Clarke, Cheryl; Schott, Kathryn; Torry, Ronald; Welty, Tim

    2015-11-25

    A 2-semester project explored employing teams of fourth-year industrial engineering students to optimize some of our academic management processes. Results included significant cost savings and increases in efficiency, effectiveness, and student and faculty satisfaction. While we did not adopt all of the students' recommendations, we did learn some important lessons. For example, an initial investment of time in developing a mutually clear understanding of the problems, constraints, and goals maximizes the value of industrial engineering analysis and recommendations. Overall, industrial engineering was a valuable tool for optimizing certain academic management processes.

  19. Engineering the just war: examination of an approach to teaching engineering ethics.

    Science.gov (United States)

    Haws, David R

    2006-04-01

    The efficiency of engineering applied to civilian projects sometimes threatens to run away with the social agenda, but in military applications, engineering often adds a devastating sleekness to the inevitable destruction of life. The relative crudeness of terrorism (e.g., 9/11) leaves a stark after-image, which belies the comparative insignificance of random (as opposed to orchestrated) belligerence. Just as engineering dwarfs the bricolage of vernacular design 'moving us past the appreciation of brush-strokes, so to speak' the scale of engineered destruction makes it difficult to focus on the charred remains of individual lives. Engineers need to guard against the inappropriate military subsumption of their effort. Fortunately, the ethics of warfare has been an ongoing topic of discussion for millennia. This paper will examine the university core class I've developed (The Moral Dimensions of Technology) to meet accreditation requirements in engineering ethics, and the discussion with engineering and non-engineering students focused by the life of electrical engineer Vannevar Bush, with selected readings in moral philosophy from the Dao de Jing, Lao Tze, Cicero, Aurelius Augustinus, Kant, Annette Baier, Peter Singer, Elizabeth Anscombe, Philippa Foot, and Judith Thomson.

  20. Engineering issue: Indoor Air Vapor Intrusion Mitigation Approaches

    Science.gov (United States)

    The US Environmental Protection Agency (EPA) Engineering Issues are a new series of technology transfer documents that summarize the latest available information on selected treatment and site remeediation technologies and related issues. They are designed to help remedial projec...

  1. A resilience engineering approach to assess major accident risks

    DEFF Research Database (Denmark)

    Hollnagel, E.

    2013-01-01

    This chapter describes how the principles of Resilience Engineering can be used to make a risk assessment of an Integrated Operations (IO) scenario. It refers to the case study provided in Chapter 12....

  2. Gas Turbine Engine Component Development : An Integrated Approach

    Directory of Open Access Journals (Sweden)

    Willem Jansen

    1988-10-01

    Full Text Available Computer - aided engineering methods have made a significant impact in the design technologies of advanced machinery. These methods have been applied in several areas such as aerodynamics and fluid dynamic theory for high efficiency, stress and vibration theory for reliability, and manufacturing strategies to produce machined components at low cost and with short time schedules. The integration of these various design technologies offer the opportunity for even greater productivity in the engineering design and manufacturing process. This paper addresses the application of various engineering disciplines to the demand of producing a reliable, efficient design and the subsequent manufacture of components with short lead times through the interaction of these computer - aided engineering technologies. The concept is further illustrated by simple cases for a centrifugal compressor and a gas turbine.

  3. Biological augmentation and tissue engineering approaches in meniscus surgery.

    Science.gov (United States)

    Moran, Cathal J; Busilacchi, Alberto; Lee, Cassandra A; Athanasiou, Kyriacos A; Verdonk, Peter C

    2015-05-01

    The purpose of this review was to evaluate the role of biological augmentation and tissue engineering strategies in meniscus surgery. Although clinical (human), preclinical (animal), and in vitro tissue engineering studies are included here, we have placed additional focus on addressing preclinical and clinical studies reported during the 5-year period used in this review in a systematic fashion while also providing a summary review of some important in vitro tissue engineering findings in the field over the past decade. A search was performed on PubMed for original works published from 2009 to March 31, 2014 using the term "meniscus" with all the following terms: "scaffolds," "constructs," "cells," "growth factors," "implant," "tissue engineering," and "regenerative medicine." Inclusion criteria were the following: English-language articles and original clinical, preclinical (in vivo), and in vitro studies of tissue engineering and regenerative medicine application in knee meniscus lesions published from 2009 to March 31, 2014. Three clinical studies and 18 preclinical studies were identified along with 68 tissue engineering in vitro studies. These reports show the increasing promise of biological augmentation and tissue engineering strategies in meniscus surgery. The role of stem cell and growth factor therapy appears to be particularly useful. A review of in vitro tissue engineering studies found a large number of scaffold types to be of promise for meniscus replacement. Limitations include a relatively low number of clinical or preclinical in vivo studies, in addition to the fact there is as yet no report in the literature of a tissue-engineered meniscus construct used clinically. Neither does the literature provide clarity on the optimal meniscus scaffold type or biological augmentation with which meniscus repair or replacement would be best addressed in the future. There is increasing focus on the role of mechanobiology and biomechanical and

  4. A resilience engineering approach to assess major accident risks

    DEFF Research Database (Denmark)

    Hollnagel, E.

    2013-01-01

    This chapter describes how the principles of Resilience Engineering can be used to make a risk assessment of an Integrated Operations (IO) scenario. It refers to the case study provided in Chapter 12.......This chapter describes how the principles of Resilience Engineering can be used to make a risk assessment of an Integrated Operations (IO) scenario. It refers to the case study provided in Chapter 12....

  5. Interactive Approach on Experiments in Mechanical Engineering : Vibration

    Science.gov (United States)

    Kumon, Makoto; Torigoe, Ippei; Mizumoto, Ikuro; Yamaguchi, Teruo; Kohzawa, Ryuichi; Ohshima, Yasutaka

    Experiments in the engineering education play important roles in motivating students to study voluntarily. A trial aiming to enhance this effect in the experiment of vibration at Mechanical System Engineering, Kumamoto University is introduced. The trial consists of 1) oral presentation by students, 2) web-based learning system and 3) feedback through reports. An evaluation by questionnaire was conducted to show the validity of this trial. This result revealed that the trial succeeded to encourage students.

  6. Hybrid Engine Powered City Car: Fuzzy Controlled Approach

    Science.gov (United States)

    Rahman, Ataur; Mohiuddin, AKM; Hawlader, MNA; Ihsan, Sany

    2017-03-01

    This study describes a fuzzy controlled hybrid engine powered car. The car is powered by the lithium ion battery capacity of 1000 Wh is charged by the 50 cc hybrid engine and power regenerative mode. The engine is operated with lean mixture at 3000 rpm to charge the battery. The regenerative mode that connects with the engine generates electrical power of 500-600 W for the deceleration of car from 90 km/h to 20 km/h. The regenerated electrical power has been used to power the air-conditioning system and to meet the other electrical power. The battery power only used to propel the car. The regenerative power also found charging the battery for longer operation about 40 minutes and more. The design flexibility of this vehicle starts with whole-vehicle integration based on radical light weighting, drag reduction, and accessory efficiency. The energy efficient hybrid engine cut carbon dioxide (CO2) and nitrogen oxides (N2O) emission about 70-80% as the loads on the crankshaft such as cam-follower and its associated rotating components are replaced by electromagnetic systems, and the flywheel, alternator and starter motor are replaced by a motor generator. The vehicle was tested and found that it was able to travel 70 km/litre with the power of hybrid engine.

  7. Computational approaches to metabolic engineering utilizing systems biology and synthetic biology.

    Science.gov (United States)

    Fong, Stephen S

    2014-08-01

    Metabolic engineering modifies cellular function to address various biochemical applications. Underlying metabolic engineering efforts are a host of tools and knowledge that are integrated to enable successful outcomes. Concurrent development of computational and experimental tools has enabled different approaches to metabolic engineering. One approach is to leverage knowledge and computational tools to prospectively predict designs to achieve the desired outcome. An alternative approach is to utilize combinatorial experimental tools to empirically explore the range of cellular function and to screen for desired traits. This mini-review focuses on computational systems biology and synthetic biology tools that can be used in combination for prospective in silico strain design.

  8. Knowledge engineering in volcanology: Practical claims and general approach

    Science.gov (United States)

    Pshenichny, Cyril A.

    2014-10-01

    Knowledge engineering, being a branch of artificial intelligence, offers a variety of methods for elicitation and structuring of knowledge in a given domain. Only a few of them (ontologies and semantic nets, event/probability trees, Bayesian belief networks and event bushes) are known to volcanologists. Meanwhile, the tasks faced by volcanology and the solutions found so far favor a much wider application of knowledge engineering, especially tools for handling dynamic knowledge. This raises some fundamental logical and mathematical problems and requires an organizational effort, but may strongly improve panel discussions, enhance decision support, optimize physical modeling and support scientific collaboration.

  9. An engineering approach to an integrated value proposition design framework

    Directory of Open Access Journals (Sweden)

    Van Der Merwe, Carmen

    2015-05-01

    Full Text Available Numerous problems with product quality and time-to-market launches can be traced back to how the product lifecycle process is managed within the organisation. This article provides insight into how an integrated value proposition design framework shifts product lifecycle management from a product-centric view to a customer-centric view, through the use of good engineering practices as found in the systems engineering discipline. Combining this with methods and tools such as the Refined Kano model, Blue Ocean strategy, and the Generalised Bass model enables the organisation to enhance product and service quality while reducing the time-to-market for new value proposition launches.

  10. Biomaterials Science An Integrated Clinical and Engineering Approach

    CERN Document Server

    Rosen, Yitzhak

    2012-01-01

    "This book is essential when designing, developing and studying biomedical materials...provides an excellent review-from a patient, disease, and even genetic point of view-of materials engineering for the biomedical field...This well presented book strongly insists on how the materials can influence patients' needs, the ultimate drive for biomedical engineering...[presents an] Interesting and innovative review from a patient focus perspective-the book emphasizes the importance of the patients, which is not often covered in other biomedical material's books." -Fanny Raisin-Dadre, BioI

  11. Quantum Information Processing and Quantum Error Correction An Engineering Approach

    CERN Document Server

    Djordjevic, Ivan

    2012-01-01

    Quantum Information Processing and Quantum Error Correction is a self-contained, tutorial-based introduction to quantum information, quantum computation, and quantum error-correction. Assuming no knowledge of quantum mechanics and written at an intuitive level suitable for the engineer, the book gives all the essential principles needed to design and implement quantum electronic and photonic circuits. Numerous examples from a wide area of application are given to show how the principles can be implemented in practice. This book is ideal for the electronics, photonics and computer engineer

  12. A systems engineering management approach to resource management applications

    Science.gov (United States)

    Hornstein, Rhoda Shaller

    1989-01-01

    The author presents a program management response to the following question: How can the traditional practice of systems engineering management, including requirements specification, be adapted, enhanced, or modified to build future planning and scheduling systems for effective operations? The systems engineering management process, as traditionally practiced, is examined. Extensible resource management systems are discussed. It is concluded that extensible systems are a partial solution to problems presented by requirements that are incomplete, partially immeasurable, and often dynamic. There are positive indications that resource management systems have been characterized and modeled sufficiently to allow their implementation as extensible systems.

  13. A Constrained and Guided Approach for Managing Software Engineering Course Projects

    Science.gov (United States)

    Cheng, Y.-P.; Lin, J. M.-C.

    2010-01-01

    This paper documents several years of experimentation with a new approach to organizing and managing projects in a software engineering course. The initial failure and subsequent refinements that the new approach has been through since 2004 are described herein. The "constrained and guided" approach, as it is called, has helped to reduce…

  14. A 'reverse network engineering' framework to develop tourism using a lifestyle approach

    NARCIS (Netherlands)

    Kamann, DJF; Strijker, D; Sijtsma, FJ

    1998-01-01

    This paper uses the network approach in the design of policies for regional development focusing on tourism in rural and peripheral areas. The methodology applied - 'reverse network engineering' - is a combination of a top-down and a bottom-up approach, The top-down approach starts with the demand s

  15. A Constrained and Guided Approach for Managing Software Engineering Course Projects

    Science.gov (United States)

    Cheng, Y.-P.; Lin, J. M.-C.

    2010-01-01

    This paper documents several years of experimentation with a new approach to organizing and managing projects in a software engineering course. The initial failure and subsequent refinements that the new approach has been through since 2004 are described herein. The "constrained and guided" approach, as it is called, has helped to reduce…

  16. A Constrained and Guided Approach for Managing Software Engineering Course Projects

    Science.gov (United States)

    Cheng, Y.-P.; Lin, J. M.-C.

    2010-01-01

    This paper documents several years of experimentation with a new approach to organizing and managing projects in a software engineering course. The initial failure and subsequent refinements that the new approach has been through since 2004 are described herein. The "constrained and guided" approach, as it is called, has helped to reduce project…

  17. The Company Approach to Software Engineering Project Courses

    Science.gov (United States)

    Broman, D.; Sandahl, K.; Abu Baker, M.

    2012-01-01

    Teaching larger software engineering project courses at the end of a computing curriculum is a way for students to learn some aspects of real-world jobs in industry. Such courses, often referred to as capstone courses, are effective for learning how to apply the skills they have acquired in, for example, design, test, and configuration management.…

  18. Appendix B: Rapid development approaches for system engineering and design

    Science.gov (United States)

    1993-01-01

    Conventional processes often produce systems which are obsolete before they are fielded. This paper explores some of the reasons for this, and provides a vision of how we can do better. This vision is based on our explorations in improved processes and system/software engineering tools.

  19. Appendix C: Rapid development approaches for system engineering and design

    Science.gov (United States)

    1993-01-01

    Conventional system architectures, development processes, and tool environments often produce systems which exceed cost expectations and are obsolete before they are fielded. This paper explores some of the reasons for this and provides recommendations for how we can do better. These recommendations are based on DoD and NASA system developments and on our exploration and development of system/software engineering tools.

  20. Reverse breeding: a novel breeding approach based on engineered meiosis

    NARCIS (Netherlands)

    Dirks, R.; Dun, van K.P.M.; Snoo, de B.; Berg, van den M.; Lelivelt, C.L.C.; Voermans, W.; Woudenberg, L.; Wit, de J.P.C.; Reinink, K.; Schut, J.W.; Jong, de J.H.S.G.M.; Wijnker, T.G.

    2009-01-01

    Reverse breeding (RB) is a novel plant breeding technique designed to directly produce parental lines for any heterozygous plant, one of the most sought after goals in plant breeding. RB generates perfectly complementing homozygous parental lines through engineered meiosis. The method is based on re

  1. The Company Approach to Software Engineering Project Courses

    Science.gov (United States)

    Broman, D.; Sandahl, K.; Abu Baker, M.

    2012-01-01

    Teaching larger software engineering project courses at the end of a computing curriculum is a way for students to learn some aspects of real-world jobs in industry. Such courses, often referred to as capstone courses, are effective for learning how to apply the skills they have acquired in, for example, design, test, and configuration management.…

  2. Scaffolding in tissue engineering: general approaches and tissue-specific considerations.

    Science.gov (United States)

    Chan, B P; Leong, K W

    2008-12-01

    Scaffolds represent important components for tissue engineering. However, researchers often encounter an enormous variety of choices when selecting scaffolds for tissue engineering. This paper aims to review the functions of scaffolds and the major scaffolding approaches as important guidelines for selecting scaffolds and discuss the tissue-specific considerations for scaffolding, using intervertebral disc as an example.

  3. An Investigation of First-Year Engineering Student and Instructor Perspectives of Learning Analytics Approaches

    Science.gov (United States)

    Knight, David B.; Brozina, Cory; Novoselich, Brian

    2016-01-01

    This paper investigates how first-year engineering undergraduates and their instructors describe the potential for learning analytics approaches to contribute to student success. Results of qualitative data collection in a first-year engineering course indicated that both students and instructors\temphasized a preference for learning analytics…

  4. A multidimensional approach to examine student interdisciplinary learning in science and engineering in higher education

    NARCIS (Netherlands)

    Spelt, Elsbeth; Luning, Pieternelleke Arianne; Boekel, van Tiny; Mulder, Martin

    2016-01-01

    Preparing science and engineering students to work in interdisciplinary teams necessitates research on teaching and learning of interdisciplinary thinking. A multidimensional approach was taken to examine student interdisciplinary learning in a master course on food quality management. The collected

  5. Banding approach for engineered nanomaterial risk assessment and control

    Science.gov (United States)

    Van Hoornick, Nausikaä; Prodanov, Dimiter; Pardon, Alain

    2017-06-01

    Since there is a lack of sufficient toxicological information about engineered nanomaterials, and since within the semiconductor research and manufacturing use is already made of these materials, an alternative for the classical quantitative risk assessment was sought. Within the research facilities of imec use is made of a banding technique to determine the risks associated with the nanomaterial research. The method and the measures that are taken are discussed in the paper. The method has been benchmarked with other available techniques.

  6. Stem Cell-based Tissue Engineering Approaches for Musculoskeletal Regeneration

    Science.gov (United States)

    Brown, Patrick T.; Handorf, Andrew M.; Jeon, Won Bae; Li, Wan-Ju

    2014-01-01

    The field of regenerative medicine and tissue engineering is an ever evolving field that holds promise in treating numerous musculoskeletal diseases and injuries. An important impetus in the development of the field was the discovery and implementation of stem cells. The utilization of mesenchymal stem cells, and later embryonic and induced pluripotent stem cells, opens new arenas for tissue engineering and presents the potential of developing stem cell-based therapies for disease treatment. Multipotent and pluripotent stem cells can produce various lineage tissues, and allow for derivation of a tissue that may be comprised of multiple cell types. As the field grows, the combination of biomaterial scaffolds and bioreactors provides methods to create an environment for stem cells that better represent their microenvironment for new tissue formation. As technologies for the fabrication of biomaterial scaffolds advance, the ability of scaffolds to modulate stem cell behavior advances as well. The composition of scaffolds could be of natural or synthetic materials and could be tailored to enhance cell self-renewal and/or direct cell fates. In addition to biomaterial scaffolds, studies of tissue development and cellular microenvironments have determined other factors, such as growth factors and oxygen tension, that are crucial to the regulation of stem cell activity. The overarching goal of stem cell-based tissue engineering research is to precisely control differentiation of stem cells in culture. In this article, we review current developments in tissue engineering, focusing on several stem cell sources, induction factors including growth factors, oxygen tension, biomaterials, and mechanical stimulation, and the internal and external regulatory mechanisms that govern proliferation and differentiation. PMID:23432679

  7. Metabolic engineering approaches for production of biochemicals in food and medicinal plants.

    Science.gov (United States)

    Wilson, Sarah A; Roberts, Susan C

    2014-04-01

    Historically, plants are a vital source of nutrients and pharmaceuticals. Recent advances in metabolic engineering have made it possible to not only increase the concentration of desired compounds, but also introduce novel biosynthetic pathways to a variety of species, allowing for enhanced nutritional or commercial value. To improve metabolic engineering capabilities, new transformation techniques have been developed to allow for gene specific silencing strategies or stacking of multiple genes within the same region of the chromosome. The 'omics' era has provided a new resource for elucidation of uncharacterized biosynthetic pathways, enabling novel metabolic engineering approaches. These resources are now allowing for advanced metabolic engineering of plant production systems, as well as the synthesis of increasingly complex products in engineered microbial hosts. The status of current metabolic engineering efforts is highlighted for the in vitro production of paclitaxel and the in vivo production of β-carotene in Golden Rice and other food crops.

  8. A General Architecture for Language Engineering (GATE) - a new approach to Language Engineering R&D

    OpenAIRE

    Cunningham, Hamish; Gaizauskas, Robert J.; Wilks, Yorick

    1996-01-01

    This report argues for the provision of a common software infrastructure for NLP systems. Current trends in Language Engineering research are reviewed as motivation for this infrastructure, and relevant recent work discussed. A freely-available system called GATE is described which builds on this work.

  9. Writing Compilers and Interpreters A Software Engineering Approach

    CERN Document Server

    Mak, Ronald

    2011-01-01

    Long-awaited revision to a unique guide that covers both compilers and interpreters Revised, updated, and now focusing on Java instead of C++, this long-awaited, latest edition of this popular book teaches programmers and software engineering students how to write compilers and interpreters using Java. You?ll write compilers and interpreters as case studies, generating general assembly code for a Java Virtual Machine that takes advantage of the Java Collections Framework to shorten and simplify the code. In addition, coverage includes Java Collections Framework, UML modeling, object-oriented p

  10. Approaches to Health Monitoring of the CAT 7 Diesel Engine

    Science.gov (United States)

    2011-09-01

    timely, efficient, and effective decision making can be made both for operations and logistical support. With this in mind , the U.S. Army Research...is the confidence level, and F is the F value from the F-distribution table: ( ) αα ,,2 1 rmrFrm mrT −− − = . (8) The SPE thresholds calculation...sense. These perturbations may or may not adversely affect engine performance. With this in mind , our work is on the detectability of the

  11. A statistical combustion phase control approach of SI engines

    Science.gov (United States)

    Gao, Jinwu; Wu, Yuhu; Shen, Tielong

    2017-02-01

    In order to maximize the performance of internal combustion engine, combustion phase is usually controlled to track its desired reference. However, suffering from the cyclic variability of combustion, it is difficulty but meaningful to control mean of combustion phase and constrain its variance. As a combustion phase indicator, the location of peak pressure (LPP) is utilized for real-time combustion phase control in this research. The purpose of the proposed method is to ensure the mean of LPP statistically tracks its reference and constrains the standard deviation of LPP distribution. To achieve this, LPP is first calculated based on the cylinder pressure sensor, and its characteristics are analyzed at the steady-state operating condition, then the distribution of LPP is examined online using hypothesis test criterion. On the basis of the presented statistical algorithm, current mean of LPP is applied in the feedback channel for designing spark advance adjustment law, and the stability of closed-loop system is theoretically ensured according to a steady statistical model. Finally, the proposed strategy is verified on a spark ignition gasoline engine.

  12. Redesigning the Student Learning Approach through Personality Types and Pedagogies, A Case Study in an Undergraduate Engineering Course

    Science.gov (United States)

    Fleischmann, Corinna; Nakagawa, Elizabeth; Kelley, Tyler

    2016-01-01

    As the National Science Foundation and engineers throughout the world seek to strengthen the future of the engineering profession, the Civil Engineering (CE) program at the United States Coast Guard Academy embodies this initiative with a student focused approach. One course in particular, Materials for Civil and Construction Engineers (CE…

  13. Requirements engineering for e-Government services: A citizen-centric approach and case study

    NARCIS (Netherlands)

    Velsen, van Lex; Geest, van der Thea; Hedde, ter Marc; Derks, Wijnand

    2009-01-01

    Throughout the last decade, user involvement in e-Government service design has been virtually non-existent. Over time, e-Government experts began to realize that these services would benefit from a citizen-centric requirements engineering approach which has led to a demand for such an approach for

  14. Requirements engineering for e-governement services: A citizen-centric approach and case study

    NARCIS (Netherlands)

    van Velsen, Lex Stefan; van der Geest, Thea; ter Hedde, M.J.; Derks, Wijnand

    2009-01-01

    Throughout the last decade, user involvement in e-Government service design has been virtually non-existent. Over time, e-Government experts began to realize that these services would benefit from a citizen-centric requirements engineering approach which has led to a demand for such an approach for

  15. Improving Student Learning in Engineering Discipline Using Student- and Lecturer-Led Assessment Approaches

    Science.gov (United States)

    Imam, Boulent; Rafiq, M. Imran; Kumar, Prashant

    2011-01-01

    This article investigates the effectiveness of two distinct formative assessment methods for promoting deep learning and hence improving the performance amongst engineering students. The first method, applied for undergraduate students, employs a lecturer-led approach whereas the second method uses a student-led approach and e-learning for…

  16. A Knowledge Engineering Approach to Developing Educational Computer Games for Improving Students' Differentiating Knowledge

    Science.gov (United States)

    Hwang, Gwo-Jen; Sung, Han-Yu; Hung, Chun-Ming; Yang, Li-Hsueh; Huang, Iwen

    2013-01-01

    Educational computer games have been recognized as being a promising approach for motivating students to learn. Nevertheless, previous studies have shown that without proper learning strategies or supportive models, the learning achievement of students might not be as good as expected. In this study, a knowledge engineering approach is proposed…

  17. An Integrated Approach to Engineering Education in a Minority Community

    Science.gov (United States)

    Taylor, Bill

    1998-01-01

    Northeastern New Mexico epitomizes regions which are economically depressed, rural, and predominantly Hispanic. New Mexico Highlands University (NMHU), with a small student population of approximately 2800, offers a familiar environment attracting students who might otherwise not attend college. An outreach computer network of minority schools was created in northeastern New Mexico with NASA funding. Rural and urban minority schools gained electronic access to each other, to computer resources, to technical help at New Mexico Highlands University and gained access to the world via the Internet. This outreach program was initiated in the fall of 1992 in an effort to attract and to involve minority students in Engineering and the Mathematical Sciences. We installed 56 Kbs Internet connections to eight elementary schools, two middle schools, two high schools, a public library (servicing the home schooling community) and an International Baccalaureate school. For another fourteen rural schools, we provided computers and free dial-up service to servers on the New Mexico Highlands University campus.

  18. Engineering interrelated electricity markets. An agent-based computational approach

    Energy Technology Data Exchange (ETDEWEB)

    Weidlich, Anke [Mannheim Univ. (Germany). Dieter Schwarz Chair of Business Administration and Information Systems

    2008-07-01

    Due to the characteristics of electricity, power markets rank among the most complex markets operated at present. The requirements of an environmentally sustainable, economically efficient, and secure energy supply have resulted in the emergence of several interrelated markets that have to be carefully engineered in order to ensure efficient market outcomes. This book presents an agent-based simulation model that facilitates electricity market research. Simulation outcomes from this model are validated against price data from German power markets. The results significantly contribute to existing research in agent-based simulation and electricity market modeling, and provide insights into the impact of the market structure and market design on electricity prices. The book addresses researchers, lecturers and students who are interested in applying agent-based simulation to power markets. It provides a thorough discussion of the methodology and helpful details for model implementation. (orig.)

  19. A Theoretical Approach to Engineering a New Enzyme

    Science.gov (United States)

    Anderson, Greg; Behera, Raghu N.; Gomatam, Ravi

    2016-08-01

    Density function theory, a subfield of quantum mechanics (QM), in combination with molecular mechanics (MM) has opened the way to engineer new artificial enzymes. Herein, we report theoretical calculations done using QM/MM to examine whether the regioselectivity and rate of chlorination of the enzyme chloroperoxidase can be improved by replacing the vanadium of this enzyme with niobium through dialysis. Our calculations show that a niobium substituted chloroperoxidase will be able to enter the initial steps of the catalytic cycle for chlorination. Although the protonation state of the niobium substituted enzyme is calculated to be different from than that of the natural vanadium substituted enzyme, our calculations show that the catalytic cycle can still proceed forward. Using natural bond orbitals, we analyse the electronic differences between the niobium substituted enzyme and the natural enzyme. We conclude by briefly examining how good of a model QM/MM provides for understanding the mechanism of catalysis of chloroperoxidase.

  20. Today prospects for tissue engineering therapeutic approach in dentistry.

    Science.gov (United States)

    Bossù, Maurizio; Pacifici, Andrea; Carbone, Daniele; Tenore, Gianluca; Ierardo, Gaetano; Pacifici, Luciano; Polimeni, Antonella

    2014-01-01

    In dental practice there is an increasing need for predictable therapeutic protocols able to regenerate tissues that, due to inflammatory or traumatic events, may suffer from loss of their function. One of the topics arising major interest in the research applied to regenerative medicine is represented by tissue engineering and, in particular, by stem cells. The study of stem cells in dentistry over the years has shown an exponential increase in literature. Adult mesenchymal stem cells have recently been isolated and characterized from tooth-related tissues and they might represent, in the near future, a new gold standard in the regeneration of all oral tissues. The aim of our review is to provide an overview on the topic reporting the current knowledge for each class of dental stem cells and to identify their potential clinical applications as therapeutic tool in various branches of dentistry.

  1. Engineering Approaches for Understanding Osteogenesis: Hydrogels as Synthetic Bone Microenvironments.

    Science.gov (United States)

    Shapiro, J M; Oyen, M L

    2016-11-01

    The microenvironment, which can be considered the sum of all the components and conditions surrounding a particular cell, is critical to moderating cellular behavior. In bone, interactions with the microenvironment can influence osteogenic differentiation, and subsequent extracellular matrix deposition, mineralization, and bone growth. Beyond regenerative medicine purposes, tissue engineering tools, namely cell-scaffold constructs, can be used as models of the bone microenvironment. Hydrogels, which are hydrophilic polymer networks, are popularly used for cell culture constructs due to their substantial water content and their ability to be tailored for specific applications. As synthetic microenvironments, a level of control can be exerted on the hydrogel structure and material properties, such that individual contributions from the scaffold on cellular behavior can be observed. Both biochemical and mechanical stimuli have been shown to modulate cellular behaviors. Hydrogels can be modified to present cell-interactive ligands, include osteoinductive moieties, vary mechanical properties, and be subject to external mechanical stimulation, all of which have been shown to affect osteogenic differentiation. Following "bottom-up" fabrication methods, levels of complexity can be introduced to hydrogel systems, such that the synergistic effects of multiple osteogenic cues can be observed. This review explores the utility of hydrogel scaffolds as synthetic bone microenvironments to observe both individual and synergistic effects from biochemical and mechanical signals on osteogenic differentiation. Ultimately, a better understanding of how material properties can influence cellular behavior will better inform design of tissue engineering scaffolds, not just for studying cell behavior, but also for regenerative medicine purposes. © Georg Thieme Verlag KG Stuttgart · New York.

  2. A Planning Approach of Engineering Characteristics Based on QFD-TRIZ Integrated

    Science.gov (United States)

    Liu, Shang; Shi, Dongyan; Zhang, Ying

    Traditional QFD planning method compromises contradictions between engineering characteristics to achieve higher customer satisfaction. However, this compromise trade-off can not eliminate the contradictions existing among the engineering characteristics which limited the overall customer satisfaction. QFD (Quality function deployment) integrated with TRIZ (the Russian acronym of the Theory of Inventive Problem Solving) becomes hot research recently for TRIZ can be used to solve contradictions between engineering characteristics which construct the roof of HOQ (House of quality). But, the traditional QFD planning approach is not suitable for QFD integrated with TRIZ for that TRIZ requires emphasizing the contradictions between engineering characteristics at problem definition stage instead of compromising trade-off. So, a new planning approach based on QFD / TRIZ integration is proposed in this paper, which based on the consideration of the correlation matrix of engineering characteristics and customer satisfaction on the basis of cost. The proposed approach suggests that TRIZ should be applied to solve contradictions at the first step, and the correlation matrix of engineering characteristics should be amended at the second step, and at next step IFR (ideal final result) must be validated, then planning execute. An example is used to illustrate the proposed approach. The application indicated that higher customer satisfaction can be met and the contradictions between the characteristic parameters are eliminated.

  3. Adapting advanced engineering design approaches to building design. Potential benefits

    NARCIS (Netherlands)

    Böhms, M.

    2006-01-01

    A number of industries continuously progress advancing their design approaches based on the changing market constraints. Examples such as car, ship and airplane manufacturing industries utilize process setups and techniques, that differ significantly from the processes and techniques used by the tra

  4. Adapting advanced engineering design approaches to building design. Potential benefits

    NARCIS (Netherlands)

    Böhms, M.

    2006-01-01

    A number of industries continuously progress advancing their design approaches based on the changing market constraints. Examples such as car, ship and airplane manufacturing industries utilize process setups and techniques, that differ significantly from the processes and techniques used by the

  5. A Blended Learning Approach to Teach Fluid Mechanics in Engineering

    Science.gov (United States)

    Rahman, Ataur

    2017-01-01

    This paper presents a case study on the teaching and learning of fluid mechanics at the University of Western Sydney (UWS), Australia, by applying a blended learning approach (BLA). In the adopted BLA, various flexible learning materials have been made available to the students such as online recorded lectures, online recorded tutorials, hand…

  6. Towards modeling future energy infrastructures - the ELECTRA system engineering approach

    DEFF Research Database (Denmark)

    Uslar, Mathias; Heussen, Kai

    2016-01-01

    Within this contribution, we provide an overview based on previous work conducted in the ELECTRA project to come up with a consistent method for modeling the ELECTRA WoC approach according to the methods established with the M/490 mandate of the European Commission. We will motivate the use of th...

  7. Environmental Engineering Approaches toward Sustainable Management of Spider Mites

    OpenAIRE

    Takeshi Suzuki

    2012-01-01

    Integrated pest management (IPM), which combines physical, biological, and chemical control measures to complementary effect, is one of the most important approaches to environmentally friendly sustainable agriculture. To expand IPM, we need to develop new pest control measures, reinforce existing measures, and investigate interactions between measures. Continued progress in the development of environmental control technologies and consequent price drops have facilitated their integration int...

  8. Towards modeling future energy infrastructures - the ELECTRA system engineering approach

    DEFF Research Database (Denmark)

    Uslar, Mathias; Heussen, Kai

    2016-01-01

    Within this contribution, we provide an overview based on previous work conducted in the ELECTRA project to come up with a consistent method for modeling the ELECTRA WoC approach according to the methods established with the M/490 mandate of the European Commission. We will motivate the use...

  9. Nonlinear approaches in engineering applications applied mechanics, vibration control, and numerical analysis

    CERN Document Server

    Jazar, Reza

    2015-01-01

    This book focuses on the latest applications of nonlinear approaches in different disciplines of engineering. For each selected topic, detailed concept development, derivations, and relevant knowledge are provided for the convenience of the readers. The topics range from dynamic systems and control to optimal approaches in nonlinear dynamics. The volume includes invited chapters from world class experts in the field. The selected topics are of great interest in the fields of engineering and physics and this book is ideal for engineers and researchers working in a broad range of practical topics and approaches. This book also: ·         Explores the most up-to-date applications and underlying principles of nonlinear approaches to problems in engineering and physics, including sections on analytic nonlinearity and practical nonlinearity ·         Enlightens readers to the conceptual significance of nonlinear approaches with examples of applications in scientific and engineering problems from v...

  10. Nonlinear approaches in engineering applications advanced analysis of vehicle related technologies

    CERN Document Server

    Dai, Liming

    2016-01-01

    This book looks at the broad field of engineering science through the lens of nonlinear approaches. Examples focus on issues in vehicle technology, including vehicle dynamics, vehicle-road interaction, steering, and control for electric and hybrid vehicles. Also included are discussions on train and tram systems, aerial vehicles, robot-human interaction, and contact and scratch analysis at the micro/nanoscale. Chapters are based on invited contributions from world-class experts in the field who advance the future of engineering by discussing the development of more optimal, accurate, efficient, and cost and energy effective systems. This book is appropriate for researchers, students, and practicing engineers who are interested in the applications of nonlinear approaches to solving engineering and science problems.

  11. Semiconductor laser engineering, reliability and diagnostics a practical approach to high power and single mode devices

    CERN Document Server

    Epperlein, Peter W

    2013-01-01

    This reference book provides a fully integrated novel approach to the development of high-power, single-transverse mode, edge-emitting diode lasers by addressing the complementary topics of device engineering, reliability engineering and device diagnostics in the same book, and thus closes the gap in the current book literature. Diode laser fundamentals are discussed, followed by an elaborate discussion of problem-oriented design guidelines and techniques, and by a systematic treatment of the origins of laser degradation and a thorough exploration of the engineering means to enhance the optical strength of the laser. Stability criteria of critical laser characteristics and key laser robustness factors are discussed along with clear design considerations in the context of reliability engineering approaches and models, and typical programs for reliability tests and laser product qualifications. Novel, advanced diagnostic methods are reviewed to discuss, for the first time in detail in book literature, performa...

  12. Model Based System Engineering Approach of a Lightweight Embedded TCP/IP

    Directory of Open Access Journals (Sweden)

    M. Z. Rashed

    2011-04-01

    Full Text Available The use of embedded software is growing very rapidly. Accessing the internet is a necessaryservice which has large range of applications in many fields. The Internet is based on TCP/IPwhich is a very important stack. Although TCP/IP is very important there is not a softwareengineering model describing it. The common method in modeling and describing TCP/IP is RFCswhich is not sufficient for software engineer and developers. Therefore there is a need for softwareengineering approach to help engineers and developers to customize their own web basedapplications for embedded systems.This research presents a model based system engineering approach of lightweight TCP/IP. Themodel contains the necessary phases for developing a lightweight TCP/IP for embedded systems.The proposed model is based on SysML as a model based system engineering language.

  13. The engineering faculty today: an approach towards consolidating academic indicators

    Directory of Open Access Journals (Sweden)

    Hernán Cortés

    2012-02-01

    Full Text Available This paper presents analysis related to some key academic aspects in the Universidad Nacional de Colombia’s Engineering Faculty on the Bogota campus. The paper has focused on three academic stages: admission, students’ academic performance throughout their studies (curriculum and our students’ results in the ECAES exam. Regarding admission, this paper has analysed our intake students’ heterogeneity, their behaviour during the different components of the admission exam and analysed the schools providing the most students and which may receive detailed feedback from our faculty. On the topic of curriculum (i.e. overall academic performance during the whole course of studies, this paper has analysed each programme’s desertion rates (average and accumulated and different courses’ academic failure rates and has evaluated the effect of socioeconomic conditions on academic performance. This paper has also analysed our students’ behaviour during the different components of the ECAES exam. Lastly, this paper has described some of the actions achieved by the faculty’s board of directors aimed at addressing some of the academic issues analysed in this document.

  14. Reactor technology assessment and selection utilizing systems engineering approach

    Science.gov (United States)

    Zolkaffly, Muhammed Zulfakar; Han, Ki-In

    2014-02-01

    The first Nuclear power plant (NPP) deployment in a country is a complex process that needs to consider technical, economic and financial aspects along with other aspects like public acceptance. Increased interest in the deployment of new NPPs, both among newcomer countries and those with expanding programs, necessitates the selection of reactor technology among commercially available technologies. This paper reviews the Systems Decision Process (SDP) of Systems Engineering and applies it in selecting the most appropriate reactor technology for the deployment in Malaysia. The integrated qualitative and quantitative analyses employed in the SDP are explored to perform reactor technology assessment and to select the most feasible technology whose design has also to comply with the IAEA standard requirements and other relevant requirements that have been established in this study. A quick Malaysian case study result suggests that the country reside with PWR (pressurized water reactor) technologies with more detailed study to be performed in the future for the selection of the most appropriate reactor technology for Malaysia. The demonstrated technology assessment also proposes an alternative method to systematically and quantitatively select the most appropriate reactor technology.

  15. [Introduction to] : "Sustainability of constructions : integrated approach to life-time structural engineering"

    OpenAIRE

    Bragança, L.; Koukkari, Heli; Blok, Rijk; Gervásio, H.; Veljkovic, Milan, ed. lit.; Plewako, Zbigniew, ed. lit.; Landolfo, Raffaele; Ungureanu, Viorel

    2010-01-01

    The main objective of the COST Action C25 ‘Sustainability of Constructions: Integrated Approach lo Life-time Structural Engineering” is to promote science-based developments in sustainable construction in Europe through the collection and collaborative analysis of scientific results concerning life-time structural engineering and especially integration of environmental assessment methods and tolls of structural engineering. Sustainability of Construction, European Science Foundation : Cost...

  16. Approach control of a gas exchange solenoid actuator for IC engines

    OpenAIRE

    Tsai, Chun-Ming

    2007-01-01

    Application of solenoid valve actuators in internal combustion engines can facilitate operations such as variable valve timing for improved efficiency and emission. Unfortunately, smooth solenoid valve landing is hard to achieve due to limited control authority, limited bandwidth, and time varying disturbances. The resultant valve impact causes unacceptable noise and component wear on the engine. To solve this ``soft seating" problem, the controller is further divided into approach and landin...

  17. Segmentation Based Approach to Dynamic Page Construction from Search Engine Results

    OpenAIRE

    K.S. Kuppusamy,; Aghila, G.

    2012-01-01

    The results rendered by the search engines are mostly a linear snippet list. With the prolific increase in the dynamism of web pages there is a need for enhanced result lists from search engines in order to cope-up with the expectations of the users. This paper proposes a model for dynamic construction of a resultant page from various results fetched by the search engine, based on the web page segmentation approach. With the incorporation of personalization through user profile during the can...

  18. CASTING DEFECT MODELING IN AN INTEGRATED COMPUTATIONAL MATERIALS ENGINEERING APPROACH

    Energy Technology Data Exchange (ETDEWEB)

    Sabau, Adrian S [ORNL

    2015-01-01

    To accelerate the introduction of new cast alloys, the simultaneous modeling and simulation of multiphysical phenomena needs to be considered in the design and optimization of mechanical properties of cast components. The required models related to casting defects, such as microporosity and hot tears, are reviewed. Three aluminum alloys are considered A356, 356 and 319. The data on calculated solidification shrinkage is presented and its effects on microporosity levels discussed. Examples are given for predicting microporosity defects and microstructure distribution for a plate casting. Models to predict fatigue life and yield stress are briefly highlighted here for the sake of completion and to illustrate how the length scales of the microstructure features as well as porosity defects are taken into account for modeling the mechanical properties. Thus, the data on casting defects, including microstructure features, is crucial for evaluating the final performance-related properties of the component. ACKNOWLEDGEMENTS This work was performed under a Cooperative Research and Development Agreement (CRADA) with the Nemak Inc., and Chrysler Co. for the project "High Performance Cast Aluminum Alloys for Next Generation Passenger Vehicle Engines. The author would also like to thank Amit Shyam for reviewing the paper and Andres Rodriguez of Nemak Inc. Research sponsored by the U. S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Vehicle Technologies Office, as part of the Propulsion Materials Program under contract DE-AC05-00OR22725 with UT-Battelle, LLC. Part of this research was conducted through the Oak Ridge National Laboratory's High Temperature Materials Laboratory User Program, which is sponsored by the U. S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Vehicle Technologies Program.

  19. The star system: A production engineering approach to STS

    Science.gov (United States)

    Angier, R. C.; Swartz, L. D.; Wilson, J. H.

    1985-01-01

    A fundamental change to the way Space Transportation System flight preparation is done is documented. It involves (1) systematic restructuring the Space Transportation System flight preparation task, to minimize its R&D content; (2) development of the Space Transportation Automated Reconfiguration (STAR) system to structure and support the remaining work flow. STAR is an integrated software system providing automation and quality control mechanisms necessary to create a production-like process. This approach was implemented using tools and methodology developed by IBM under NASA contract, to produce payload flight data requirements. It offers increased product quality, reduced cost per flight, and greater responsiveness to change.

  20. Segmentation Based Approach to Dynamic Page Construction from Search Engine Results

    CERN Document Server

    Kuppusamy, K S

    2012-01-01

    The results rendered by the search engines are mostly a linear snippet list. With the prolific increase in the dynamism of web pages there is a need for enhanced result lists from search engines in order to cope-up with the expectations of the users. This paper proposes a model for dynamic construction of a resultant page from various results fetched by the search engine, based on the web page segmentation approach. With the incorporation of personalization through user profile during the candidate segment selection, the enriched resultant page is constructed. The benefits of this approach include instant, one-shot navigation to relevant portions from various result items, in contrast to a linear page-by-page visit approach. The experiments conducted on the prototype model with various levels of users, quantifies the improvements in terms of amount of relevant information fetched.

  1. An approach for IC engine coolant energy recovery based on low-temperature organic Rankine cycle

    Institute of Scientific and Technical Information of China (English)

    付建勤; 刘敬平; 徐政欣; 邓帮林; 刘琦

    2015-01-01

    To promote the fuel utilization efficiency of IC engine, an approach was proposed for IC engine coolant energy recovery based on low-temperature organic Rankine cycle (ORC). The ORC system uses IC engine coolant as heat source, and it is coupled to the IC engine cooling system. After various kinds of organic working media were compared, R124 was selected as the ORC working medium. According to IC engine operating conditions and coolant energy characteristics, the major parameters of ORC system were preliminary designed. Then, the effects of various parameters on cycle performance and recovery potential of coolant energy were analyzed via cycle process calculation. The results indicate that cycle efficiency is mainly influenced by the working pressure of ORC, while the maximum working pressure is limited by IC engine coolant temperature. At the same working pressure, cycle efficiency is hardly affected by both the mass flow rate and temperature of working medium. When the bottom cycle working pressure arrives at the maximum allowable value of 1.6 MPa, the fuel utilization efficiency of IC engine could be improved by 12.1%. All these demonstrate that this low-temperature ORC is a useful energy-saving technology for IC engine.

  2. A Semantic Query Transformation Approach Based on Ontology for Search Engine

    Directory of Open Access Journals (Sweden)

    SAJENDRA KUMAR

    2012-05-01

    Full Text Available These days we are using some popular web search engines for information retrieval in all areas, such engine are as Google, Yahoo!, and Live Search, etc. to obtain initial helpful information.Which information we retrieved via search engine may not be relevant to the search target in the search engine user's mind. When user not found relevant information he has to shortlist the results. Thesesearch engines use traditional search service based on "static keywords", which require the users to type in the exact keywords. This approach clearly puts the users in a critical situation of guessing the exact keyword. The users may want to define their search by using attributes of the search target. But the relevancy of results in most cases may not be satisfactory and the users may not be patient enough to browse through complete list of pages to get a relevant result. The reason behind this is the search engines performs search based on the syntax not on semantics. But they seemed to be less efficient to understand the relationship between the keywords which had an adverse effect on the results it produced. Semantic search engines – only solution to this; which returns concepts not documents according to user query matching. In This paper we proposed a semantic query interface which creates a semantic query according the user input query and study of current semantic search engine techniques for semantic search.

  3. Linking biomedical engineering ethics case study approach and policy.

    Science.gov (United States)

    Dibrell, William; Dobie, Elizabeth Ann

    2007-01-01

    In this paper we link bioengineering case study methods to the development of policy. The case study approach to ethics is an excellent way to show the complex nature of practical/moral reasoning. This approach can, however, lead to a kind of overwhelming complexity. The individual nature of each case makes it difficult to identify the most important information and difficult to see what moral considerations are most relevant. In order to make the overwhelming complexity less debilitating, we present a framework for moral decision making derived from suggestions made by W.D. Ross and Virginia Held. Ross articulates the multiple sources of morality and Held deepens the discussion by reminding us of the foundational importance of care and sympathy to our moral natures. We show how to use the notion of prima facie duty and discuss moral conflict. In doing this, we show how the framework, applied to cases, can be of assistance in helping us develop policies and codes of ethics with sufficient plasticity to be useful in the complex world of the bioengineer.

  4. Biogas Production Modelling: A Control System Engineering Approach

    Science.gov (United States)

    Stollenwerk, D.; Rieke, C.; Dahmen, M.; Pieper, M.

    2016-03-01

    Due to the Renewable Energy Act, in Germany it is planned to increase the amount of renewable energy carriers up to 60%. One of the main problems is the fluctuating supply of wind and solar energy. Here biogas plants provide a solution, because a demand-driven supply is possible. Before running such a plant, it is necessary to simulate and optimize the process feeding strategy. Current simulation models are either very detailed like the ADM 1, which leads to very long optimization runtimes or not accurate enough to handle the biogas production kinetics. Therefore this paper provides a new model of a biogas plant, which is easy to parametrize but also has the needed accuracy for the output prediction. It is based on the control system approach of system identification and validated with laboratory results of a real biogas production testing facility.

  5. Environmental Engineering Approaches toward Sustainable Management of Spider Mites.

    Science.gov (United States)

    Suzuki, Takeshi

    2012-10-26

    Integrated pest management (IPM), which combines physical, biological, and chemical control measures to complementary effect, is one of the most important approaches to environmentally friendly sustainable agriculture. To expand IPM, we need to develop new pest control measures, reinforce existing measures, and investigate interactions between measures. Continued progress in the development of environmental control technologies and consequent price drops have facilitated their integration into plant production and pest control. Here I describe environmental control technologies for the IPM of spider mites through: (1) the disturbance of photoperiod-dependent diapause by artificial light, which may lead to death in seasonal environments; (2) the use of ultraviolet radiation to kill or repel mites; and (3) the use of water vapor control for the long-term cold storage of commercially available natural enemies. Such environmental control technologies have great potential for the efficient control of spider mites through direct physical effects and indirect effects via natural enemies.

  6. Environmental Engineering Approaches toward Sustainable Management of Spider Mites

    Directory of Open Access Journals (Sweden)

    Takeshi Suzuki

    2012-10-01

    Full Text Available Integrated pest management (IPM, which combines physical, biological, and chemical control measures to complementary effect, is one of the most important approaches to environmentally friendly sustainable agriculture. To expand IPM, we need to develop new pest control measures, reinforce existing measures, and investigate interactions between measures. Continued progress in the development of environmental control technologies and consequent price drops have facilitated their integration into plant production and pest control. Here I describe environmental control technologies for the IPM of spider mites through: (1 the disturbance of photoperiod-dependent diapause by artificial light, which may lead to death in seasonal environments; (2 the use of ultraviolet radiation to kill or repel mites; and (3 the use of water vapor control for the long-term cold storage of commercially available natural enemies. Such environmental control technologies have great potential for the efficient control of spider mites through direct physical effects and indirect effects via natural enemies.

  7. Orion Flight Test 1 Architecture: Observed Benefits of a Model Based Engineering Approach

    Science.gov (United States)

    Simpson, Kimberly A.; Sindiy, Oleg V.; McVittie, Thomas I.

    2012-01-01

    This paper details how a NASA-led team is using a model-based systems engineering approach to capture, analyze and communicate the end-to-end information system architecture supporting the first unmanned orbital flight of the Orion Multi-Purpose Crew Exploration Vehicle. Along with a brief overview of the approach and its products, the paper focuses on the observed program-level benefits, challenges, and lessons learned; all of which may be applied to improve system engineering tasks for characteristically similarly challenges

  8. [An object-oriented intelligent engineering design approach for lake pollution control].

    Science.gov (United States)

    Zou, Rui; Zhou, Jing; Liu, Yong; Zhu, Xiang; Zhao, Lei; Yang, Ping-Jian; Guo, Huai-Cheng

    2013-03-01

    Regarding the shortage and deficiency of traditional lake pollution control engineering techniques, a new lake pollution control engineering approach was proposed in this study, based on object-oriented intelligent design (OOID) from the perspective of intelligence. It can provide a new methodology and framework for effectively controlling lake pollution and improving water quality. The differences between the traditional engineering techniques and the OOID approach were compared. The key points for OOID were described as object perspective, cause and effect foundation, set points into surface, and temporal and spatial optimization. The blue algae control in lake was taken as an example in this study. The effect of algae control and water quality improvement were analyzed in details from the perspective of object-oriented intelligent design based on two engineering techniques (vertical hydrodynamic mixer and pumping algaecide recharge). The modeling results showed that the traditional engineering design paradigm cannot provide scientific and effective guidance for engineering design and decision-making regarding lake pollution. Intelligent design approach is based on the object perspective and quantitative causal analysis in this case. This approach identified that the efficiency of mixers was much higher than pumps in achieving the goal of low to moderate water quality improvement. However, when the objective of water quality exceeded a certain value (such as the control objective of peak Chla concentration exceeded 100 microg x L(-1) in this experimental water), the mixer cannot achieve this goal. The pump technique can achieve the goal but with higher cost. The efficiency of combining the two techniques was higher than using one of the two techniques alone. Moreover, the quantitative scale control of the two engineering techniques has a significant impact on the actual project benefits and costs.

  9. Emerging nanotechnology approaches in tissue engineering and regenerative medicine

    Directory of Open Access Journals (Sweden)

    Kim ES

    2014-05-01

    Full Text Available Eung-Sam Kim,1,2 Eun Hyun Ahn,3,4 Tal Dvir,5,6 Deok-Ho Kim1,4,71Department of Bioengineering, University of Washington, Seattle, WA, USA; 2Department of Biological Sciences, Chonnam National University, Gwangju, Korea; 3Department of Pathology, 4Institute of Stem Cell and Regenerative Medicine, School of Medicine, University of Washington, Seattle, WA, USA; 5Department of Molecular Microbiology and Biotechnology, 6Center for Nanoscience and Nanotechnology, Tel Aviv University, Tel Aviv, Israel; 7Center for Cardiovascular Biology, University of Washington, Seattle, WA, USAThe history of human kind suggests that there has been a correlation between global population growth and major events in science and technology over the last three centuries. Sharp increases in the world’s population have been triggered by the industrial revolution and scientific and technological breakthroughs including: the advent of the railways, discovery of penicillin and deoxyribonucleic acid (DNA, and the invention of the computer.1 Since the 20th century, interdisciplinary areas in the physical and biological sciences have accelerated the progress of biomedical applications. The recent integration of emerging nanotechnology into biology and biomedicine has resulted in a range of innovative nanoengineering efforts for the repair and regeneration of tissues and organs.2 Thus, it is expected that nanoengineering approaches to biomedical applications can contribute to addressing the present issue of personal and global health care and its economic burden for more than 7 billion people.Why are we paying attention to nanoengineering for biomedical applications? The size of most biomolecules ranges from 0.2 nm to 200 nm (Figure 1. Research has focused on control of the interaction and localization of biomolecules even at the single-molecule level using ever-evolving nanotechnology.3 The evidence indicates that cells can respond to nanoscale changes in the dynamic

  10. CubeSat mission design based on a systems engineering approach

    Science.gov (United States)

    Asundi, S. A.; Fitz-Coy, N. G.

    With the exception of the CubeSat specification, CubeSat design and development approaches have been mostly ad hoc, which has questioned their reliability. A systems engineering approach, based on the guidelines of NASA's Systems Engineering Handbook has been developed for CubeSats to facilitate systematic design, development and address their reliability, traceability, and reusability. The CubeSat systems engineering approach, developed as a repeatable process, uses a top-down design methodology to translate mission definitions into basic building blocks, components, interfaces and tasks, that then facilitate a bottom-up development and fabrication process. Some of the design tools (e.g., N2 diagram) described in NASAs Systems Engineering Handbook are utilized early in the design phase to identify potential conflicts in the mechanical and electrical interfaces. A novel subsystem level flowdown, which transcribes the system level requirements into identifiable CubeSat subsystems, (i.e., building blocks) is described. Utilizing this approach yields full traceability from mission concept to subsystem component to flight software. Additionally, the approach facilitates the estimation of the mission overhead in terms of power, telemetry, and computation associated with each component, interface, and task.

  11. Engineering a Multimission Approach to Navigation Ground Data System Operations

    Science.gov (United States)

    Gerasimatos, Dimitrios V.; Attiyah, Ahlam A.

    2012-01-01

    The Mission Design and Navigation (MDNAV) Section at the Jet Propulsion Laboratory (JPL) supports many deep space and earth orbiting missions from formulation to end of mission operations. The requirements of these missions are met with a multimission approach to MDNAV ground data system (GDS) infrastructure capable of being shared and allocated in a seamless and consistent manner across missions. The MDNAV computing infrastructure consists of compute clusters, network attached storage, mission support area facilities, and desktop hardware. The multimission architecture allows these assets, and even personnel, to be leveraged effectively across the project lifecycle and across multiple missions simultaneously. It provides a more robust and capable infrastructure to each mission than might be possible if each constructed its own. It also enables a consistent interface and environment within which teams can conduct all mission analysis and navigation functions including: trajectory design; ephemeris generation; orbit determination; maneuver design; and entry, descent, and landing analysis. The savings of these efficiencies more than offset the costs of increased complexity and other challenges that had to be addressed: configuration management, scheduling conflicts, and competition for resources. This paper examines the benefits of the multimission MDNAV ground data system infrastructure, focusing on the hardware and software architecture. The result is an efficient, robust, scalable MDNAV ground data system capable of supporting more than a dozen active missions at once.

  12. A Programmatic and Engineering Approach to the Development of a Nuclear Thermal Rocket for Space Exploration

    Science.gov (United States)

    Bordelon, Wayne J., Jr.; Ballard, Rick O.; Gerrish, Harold P., Jr.

    2006-01-01

    With the announcement of the Vision for Space Exploration on January 14, 2004, there has been a renewed interest in nuclear thermal propulsion. Nuclear thermal propulsion is a leading candidate for in-space propulsion for human Mars missions; however, the cost to develop a nuclear thermal rocket engine system is uncertain. Key to determining the engine development cost will be the engine requirements, the technology used in the development and the development approach. The engine requirements and technology selection have not been defined and are awaiting definition of the Mars architecture and vehicle definitions. The paper discusses an engine development approach in light of top-level strategic questions and considerations for nuclear thermal propulsion and provides a suggested approach based on work conducted at the NASA Marshall Space Flight Center to support planning and requirements for the Prometheus Power and Propulsion Office. This work is intended to help support the development of a comprehensive strategy for nuclear thermal propulsion, to help reduce the uncertainty in the development cost estimate, and to help assess the potential value of and need for nuclear thermal propulsion for a human Mars mission.

  13. Tissue-engineering strategies to repair joint tissue in osteoarthritis: nonviral gene-transfer approaches.

    Science.gov (United States)

    Madry, Henning; Cucchiarini, Magali

    2014-10-01

    Loss of articular cartilage is a common clinical consequence of osteoarthritis (OA). In the past decade, substantial progress in tissue engineering, nonviral gene transfer, and cell transplantation have provided the scientific foundation for generating cartilaginous constructs from genetically modified cells. Combining tissue engineering with overexpression of therapeutic genes enables immediate filling of a cartilage defect with an engineered construct that actively supports chondrogenesis. Several pioneering studies have proved that spatially defined nonviral overexpression of growth-factor genes in constructs of solid biomaterials or hydrogels is advantageous compared with gene transfer or scaffold alone, both in vitro and in vivo. Notably, these investigations were performed in models of focal cartilage defects, because advanced cartilage-repair strategies based on the principles of tissue engineering have not advanced sufficiently to enable resurfacing of extensively degraded cartilage as therapy for OA. These studies serve as prototypes for future technological developments, because they raise the possibility that cartilage constructs engineered from genetically modified chondrocytes providing autocrine and paracrine stimuli could similarly compensate for the loss of articular cartilage in OA. Because cartilage-tissue-engineering strategies are already used in the clinic, combining tissue engineering and nonviral gene transfer could prove a powerful approach to treat OA.

  14. Knowledge management through the e-learning approach - a case study of online engineering courses

    Science.gov (United States)

    Aichouni, Mohamed; Benchicou, Soraya; Nehari, Dris

    2013-06-01

    Though it is universally accepted that the face-to-face approach is the best way for education and training, however, with the advent of the information and communication technologies (mainly the World Wide Web) it became possible to enhance further the methods we are using to teach our students and to share the teaching material within a broaden engineering, technical and business communities. This paper is dedicated to making a review of the basic concepts of knowledge management and e-learning and to show how these two modern concepts can be integrated into engineering education to produce knowledge, disseminate it and share it within virtual interest groups and networks of engineering students, academic teachers and industrial engineers and technicians and business managers. A practical case study will be presented and discussed.

  15. Assimilation of Usability Engineering and User-Centered Design using Agile Software Development Approach

    Directory of Open Access Journals (Sweden)

    Hina Iqbal

    2014-10-01

    Full Text Available Various agile software development methodologies, since their commencement, encouraged the development of high quality software product. Quality of a product is the compelling trait that plays a vital role in any product's success. Usability engineering and User centered design are user-centered approaches, covering the customer's concerns. The way these approaches are understood and carried out with agile practices is not properly understood and adopted till now. For software applications to be usable and valuable it is necessary to understand the correct user requirements in order to develop the interface that is usable and valuable to the customer. In this research work, we are discussing the scrum approach of agile development and integrate this with the usability engineering and user centered design approaches which helps the agile development team to understand usability demand of users and develop a product according to their expectations.

  16. Combining engineering and data-driven approaches: Development of a generic fire risk model facilitating calibration

    DEFF Research Database (Denmark)

    De Sanctis, G.; Fischer, K.; Kohler, J.

    2014-01-01

    Fire risk models support decision making for engineering problems under the consistent consideration of the associated uncertainties. Empirical approaches can be used for cost-benefit studies when enough data about the decision problem are available. But often the empirical approaches...... a generic risk model that is calibrated to observed fire loss data. Generic risk models assess the risk of buildings based on specific risk indicators and support risk assessment at a portfolio level. After an introduction to the principles of generic risk assessment, the focus of the present paper...... are not detailed enough. Engineering risk models, on the other hand, may be detailed but typically involve assumptions that may result in a biased risk assessment and make a cost-benefit study problematic. In two related papers it is shown how engineering and data-driven modeling can be combined by developing...

  17. A Story-Telling Approach for a Software Engineering Course Design

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak

    2009-01-01

    Advanced programming and software engineering techniques are challenging to learn due to their inherent complexity. However, to the average student they are even more challenging because they have never experienced the context in which the techniques are appropriate. For instance, why learn design...... patterns to increase maintainability when student exercises are never maintained? In this paper, we outline the contextual problems that software engineering teaching has to deal with and present a story telling approach for course design as a remedy. We outline the stories that over the last five years...... have structured lecturing and mandatory exercises for our advanced programming/software engineering course, and present benefits, liabilities, and experiences with the approach comparing it to the normal, topic structured, course design....

  18. Nonlinear control for a diesel engine: A CLF-based approach

    Directory of Open Access Journals (Sweden)

    Kuzmych Olena

    2014-12-01

    Full Text Available In this paper, we propose a control Lyapunov function based on a nonlinear controller for a turbocharged diesel engine. A model-based approach is used which predicts the experimentally observed engine performance for a biodiesel. The basic idea is to develop an inverse optimal control and to employ a Lyapunov function in order to achieve good performances. The obtained controller gain guarantees the global convergence of the system and regulates the flows for the variable geometry turbocharger as well as exhaust gas recirculation systems in order to minimize the NOx emission and the smoke of a biodiesel engine. Simulation of the control performances based on professional software and experimental results show the effectiveness of this approach.

  19. Optimizing Online Suicide Prevention: A Search Engine-Based Tailored Approach.

    Science.gov (United States)

    Arendt, Florian; Scherr, Sebastian

    2016-10-14

    Search engines are increasingly used to seek suicide-related information online, which can serve both harmful and helpful purposes. Google acknowledges this fact and presents a suicide-prevention result for particular search terms. Unfortunately, the result is only presented to a limited number of visitors. Hence, Google is missing the opportunity to provide help to vulnerable people. We propose a two-step approach to a tailored optimization: First, research will identify the risk factors. Second, search engines will reweight algorithms according to the risk factors. In this study, we show that the query share of the search term "poisoning" on Google shows substantial peaks corresponding to peaks in actual suicidal behavior. Accordingly, thresholds for showing the suicide-prevention result should be set to the lowest levels during the spring, on Sundays and Mondays, on New Year's Day, and on Saturdays following Thanksgiving. Search engines can help to save lives globally by utilizing a more tailored approach to suicide prevention.

  20. Segmentation Based Approach to Dynamic Page Construction from Search Engine Results

    Directory of Open Access Journals (Sweden)

    K.S. Kuppusamy,

    2011-03-01

    Full Text Available The results rendered by the search engines are mostly a linear snippet list. With the prolific increase in the dynamism of web pages there is a need for enhanced result lists from search engines inorder to cope-up with the expectations of the users. This paper proposes a model for dynamic construction of a resultant page from various results fetched by the search engine, based on the web pagesegmentation approach. With the incorporation of personalization through user profile during the candidate segment selection, the enriched resultant page is constructed. The benefits of this approachinclude instant, one-shot navigation to relevant portions from various result items, in contrast to a linear page-by-page visit approach. The experiments conducted on the prototype model with various levels of users, quantifies the improvements in terms of amount of relevant information fetched.

  1. Stennis Space Center's approach to liquid rocket engine health monitoring using exhaust plume diagnostics

    Science.gov (United States)

    Gardner, D. G.; Tejwani, G. D.; Bircher, F. E.; Loboda, J. A.; Van Dyke, D. B.; Chenevert, D. J.

    1991-01-01

    Details are presented of the approach used in a comprehensive program to utilize exhaust plume diagnostics for rocket engine health-and-condition monitoring and assessing SSME component wear and degradation. This approach incorporates both spectral and video monitoring of the exhaust plume. Video monitoring provides qualitative data for certain types of component wear while spectral monitoring allows both quantitative and qualitative information. Consideration is given to spectral identification of SSME materials and baseline plume emissions.

  2. Fast engineering optimization: A novel highly effective control parameterization approach for industrial dynamic processes.

    Science.gov (United States)

    Liu, Ping; Li, Guodong; Liu, Xinggao

    2015-09-01

    Control vector parameterization (CVP) is an important approach of the engineering optimization for the industrial dynamic processes. However, its major defect, the low optimization efficiency caused by calculating the relevant differential equations in the generated nonlinear programming (NLP) problem repeatedly, limits its wide application in the engineering optimization for the industrial dynamic processes. A novel highly effective control parameterization approach, fast-CVP, is first proposed to improve the optimization efficiency for industrial dynamic processes, where the costate gradient formulae is employed and a fast approximate scheme is presented to solve the differential equations in dynamic process simulation. Three well-known engineering optimization benchmark problems of the industrial dynamic processes are demonstrated as illustration. The research results show that the proposed fast approach achieves a fine performance that at least 90% of the computation time can be saved in contrast to the traditional CVP method, which reveals the effectiveness of the proposed fast engineering optimization approach for the industrial dynamic processes. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  3. Teaching English for Science and Technology: An Approach for Reading with Engineering English

    Science.gov (United States)

    Porcaro, James W.

    2013-01-01

    Recognizing the relevance of English for Specific Purposes, this article outlines an approach for using authentic readings in a course in Engineering English. The article describes the importance of needs analysis, rhetorical focus, and reading for content; it suggests content for 15 lessons and provides a sample worksheet and other suggestions…

  4. Approaches to the safety assessment of engineered nanomaterials (ENM) in food

    NARCIS (Netherlands)

    Cockburn, A.; Bradford, R.; Buck, N.; Kampers, F.W.H.

    2012-01-01

    A systematic, tiered approach to assess the safety of engineered nanomaterials (ENMs) in foods is presented. The ENM is first compared to its non-nano form counterpart to determine if ENM-specific assessment is required. Of highest concern from a toxicological perspective are ENMs which have potenti

  5. An industrial engineering approach to laboratory automation for high throughput screening

    OpenAIRE

    Menke, Karl C.

    2000-01-01

    Across the pharmaceutical industry, there are a variety of approaches to laboratory automation for high throughput screening. At Sphinx Pharmaceuticals, the principles of industrial engineering have been applied to systematically identify and develop those automated solutions that provide the greatest value to the scientists engaged in lead generation.

  6. An Integrated Approach to Develop Professional and Technical Skills for Informatics Engineering Students

    Science.gov (United States)

    Fernandes, Joao M.; Van Hattum-Janssen, Natascha; Ribeiro, Antonio Nestor; Fonte, Victor; Santos, Luis Paulo; Sousa, Pedro

    2012-01-01

    Many of the current approaches used in teaching and learning in engineering education are not the most appropriate to prepare students for the challenges they will face in their professional careers. The active involvement of students in their learning process facilitates the development of the technical and professional competencies they need as…

  7. A goal-oriented approach to identify and engineer ;and use systems.

    NARCIS (Netherlands)

    Hengsdijk, H.; Ittersum, van M.K.

    2002-01-01

    This paper describes a formalized approach to identify and engineer future-oriented land use systems. Such land use systems can be used to explore options for strategic decision making with respect to land use policy and to do ex-ante assessment of land use alternatives to be further tested or

  8. Animal models of temporomandibular joint disorders: implications for tissue engineering approaches.

    Science.gov (United States)

    Almarza, Alejandro J; Hagandora, Catherine K; Henderson, Sarah E

    2011-10-01

    Animal models for temporomandibular joint disorder (TMD) or degradation are necessary for assessing the value of current and future tissue engineering therapies. After reviewing the literature, it is quite apparent that most TMD animal studies can be categorized into chemical approaches or surgical/mechanical approaches. Overall, it was found that the top five cited manuscripts for all chemical models were cited by almost 40% more manuscripts than the top five manuscripts for surgical/mechanical models. It is clear that the chemical approaches have focused on the inflammatory aspect of TMDs and its relationship to pain. However, chemical irritants must be tested in larger animal models, and the effect of short-term inflammation on the mechanical properties of the fibrocartilage must be examined. Nevertheless, therapeutic approaches aimed at reducing or controlling inflammation could use the established chemical methods. Surgical/mechanical methods can be used as negative controls for first generation TMJ tissue engineering approaches when the therapy is applied immediately after injury. Next generation tissue engineering approaches will require testing on tissues degenerated for a few months after the surgical/mechanical methods, with enhanced functional assessment techniques.

  9. Avoid, Control, Succumb, or Balance: Engineering Students' Approaches to a Wicked Sustainability Problem

    Science.gov (United States)

    Lönngren, Johanna; Ingerman, Åke; Svanström, Magdalena

    2016-07-01

    Wicked sustainability problems (WSPs) are an important and particularly challenging type of problem. Science and engineering education can play an important role in preparing students to deal with such problems, but current educational practice may not adequately prepare students to do so. We address this gap by providing insights related to students' abilities to address WSPs. Specifically, we aim to (I) describe key constituents of engineering students' approaches to a WSP, (II) evaluate these approaches in relation to the normative context of education for sustainable development (ESD), and (III) identify relevant aspects of learning related to WSPs. Aim I is addressed through a phenomenographic study, while aims II and III are addressed by relating the results to research literature about human problem solving, sustainable development, and ESD. We describe four qualitatively different ways of approaching a specific WSP, as the outcome of the phenomenographic study: A. Simplify and avoid, B. Divide and control, C. Isolate and succumb, and D. Integrate and balance. We identify approach D as the most appropriate approach in the context of ESD, while A and C are not. On this basis, we identify three learning objectives related to students' abilities to address WSPs: learn to use a fully integrative approach, distinguish WSPs from tame and well-structured problems, and understand and consider the normative context of SD. Finally, we provide recommendations for how these learning objectives can be used to guide the design of science and engineering educational activities.

  10. Enhancement of lipid production using biochemical, genetic and transcription factor engineering approaches.

    Science.gov (United States)

    Courchesne, Noémie Manuelle Dorval; Parisien, Albert; Wang, Bei; Lan, Christopher Q

    2009-04-20

    This paper compares three possible strategies for enhanced lipid overproduction in microalgae: the biochemical engineering (BE) approaches, the genetic engineering (GE) approaches, and the transcription factor engineering (TFE) approaches. The BE strategy relies on creating a physiological stress such as nutrient-starvation or high salinity to channel metabolic fluxes to lipid accumulation. The GE strategy exploits our understanding to the lipid metabolic pathway, especially the rate-limiting enzymes, to create a channelling of metabolites to lipid biosynthesis by overexpressing one or more key enzymes in recombinant microalgal strains. The TFE strategy is an emerging technology aiming at enhancing the production of a particular metabolite by means of overexpressing TFs regulating the metabolic pathways involved in the accumulation of target metabolites. Currently, BE approaches are the most established in microalgal lipid production. The TFE is a very promising strategy because it may avoid the inhibitive effects of the BE approaches and the limitation of "secondary bottlenecks" as commonly observed in the GE approaches. However, it is still a novel concept to be investigated systematically.

  11. Avoid, Control, Succumb, or Balance: Engineering Students' Approaches to a Wicked Sustainability Problem

    Science.gov (United States)

    Lönngren, Johanna; Ingerman, Åke; Svanström, Magdalena

    2017-08-01

    Wicked sustainability problems (WSPs) are an important and particularly challenging type of problem. Science and engineering education can play an important role in preparing students to deal with such problems, but current educational practice may not adequately prepare students to do so. We address this gap by providing insights related to students' abilities to address WSPs. Specifically, we aim to (I) describe key constituents of engineering students' approaches to a WSP, (II) evaluate these approaches in relation to the normative context of education for sustainable development (ESD), and (III) identify relevant aspects of learning related to WSPs. Aim I is addressed through a phenomenographic study, while aims II and III are addressed by relating the results to research literature about human problem solving, sustainable development, and ESD. We describe four qualitatively different ways of approaching a specific WSP, as the outcome of the phenomenographic study: A. Simplify and avoid, B. Divide and control, C. Isolate and succumb, and D. Integrate and balance. We identify approach D as the most appropriate approach in the context of ESD, while A and C are not. On this basis, we identify three learning objectives related to students' abilities to address WSPs: learn to use a fully integrative approach, distinguish WSPs from tame and well-structured problems, and understand and consider the normative context of SD. Finally, we provide recommendations for how these learning objectives can be used to guide the design of science and engineering educational activities.

  12. Shaping the Future Landscape: Catchment Systems Engineering and the Decision Support Matrix Approach

    Science.gov (United States)

    Hewett, Caspar; Quinn, Paul; Wilkinson, Mark; Wainwright, John

    2017-04-01

    Land degradation is widely recognised as one of the great environmental challenges facing humanity today, much of which is directly associated with human activity. The negative impacts of climate change and of the way in which we have engineered the landscape through, for example, agriculture intensification and deforestation, need to be addressed. However, the answer is not a simple matter of doing the opposite of current practice. Nor is non-intervention a viable option. There is a need to bring together approaches from the natural and social sciences both to understand the issues and to act to solve real problems. We propose combining a Catchment Systems Engineering (CSE) approach that builds on existing approaches such as Natural Water Retention Measures, Green infrastructure and Nature-Based Solutions with a multi-scale framework for decision support that has been successfully applied to diffuse pollution and flood risk management. The CSE philosophy follows that of Earth Systems Engineering and Management, which aims to engineer and manage complex coupled human-natural systems in a highly integrated, rational manner. CSE is multi-disciplinary, and necessarily involves a wide range of subject areas including anthropology, engineering, environmental science, ethics and philosophy. It offers a rational approach which accepts the fact that we need to engineer and act to improve the functioning of the existing catchment entity on which we rely. The decision support framework proposed draws on physical and mathematical modelling; Participatory Action Research; and demonstration sites at which practical interventions are implemented. It is predicated on the need to work with stakeholders to co-produce knowledge that leads to proactive interventions to reverse the land degradation we observe today while sustaining the agriculture humanity needs. The philosophy behind CSE and examples of where it has been applied successfully are presented. The Decision Support Matrix

  13. Developing Novel Therapeutic Approaches in Small Cell Lung Carcinoma Using Genetically Engineered Mouse Models and Human Circulating Tumor Cells

    Science.gov (United States)

    2015-10-01

    Using Genetically Engineered Mouse Models and Human Circulating Tumor Cells PRINCIPAL INVESTIGATOR: Jeffrey Engelman MD PhD CONTRACTING...SUBTITLE Developiing Novel Therapeutic Approaches in Small Cell Lung 5a. CONTRACT NUMBER Carcinoma Using Genetically Engineered Mouse Models and 5b...biomarkers. 15. SUBJECT TERMS Small cell lung cancer (SCLC), Genetically engineered mouse model (GEMM), BH3 mimetic, TORC inhibitor, Apoptosis

  14. Regenerative endodontics as a tissue engineering approach: past, current and future.

    Science.gov (United States)

    Malhotra, Neeraj; Mala, Kundabala

    2012-12-01

    With the reported startling statistics of high incidence of tooth decay and tooth loss, the current interest is focused on the development of alternate dental tissue replacement therapies. This has led to the application of dental tissue engineering as a clinically relevant method for the regeneration of dental tissues and generation of bioengineered whole tooth. Although, tissue engineering approach requires the three main key elements of stem cells, scaffold and morphogens, a conductive environment (fourth element) is equally important for successful engineering of any tissue and/or organ. The applications of this science has evolved continuously in dentistry, beginning from the application of Ca(OH)(2) in vital pulp therapy to the development of a fully functional bioengineered tooth (mice). Thus, with advances in basic research, recent reports and studies have shown successful application of tissue engineering in the field of dentistry. However, certain practical obstacles are yet to be overcome before dental tissue regeneration can be applied as evidence-based approach in clinics. The article highlights on the past achievements, current developments and future prospects of tissue engineering and regenerative therapy in the field of endodontics and bioengineered teeth (bioteeth). © 2012 The Authors. Australian Endodontic Journal © 2012 Australian Society of Endodontology.

  15. Recent Progress on Systems and Synthetic Biology Approaches to Engineer Fungi As Microbial Cell Factories.

    Science.gov (United States)

    Amores, Gerardo Ruiz; Guazzaroni, María-Eugenia; Arruda, Letícia Magalhães; Silva-Rocha, Rafael

    2016-04-01

    Filamentous fungi are remarkable organisms naturally specialized in deconstructing plant biomass and this feature has a tremendous potential for biofuel production from renewable sources. The past decades have been marked by a remarkable progress in the genetic engineering of fungi to generate industry-compatible strains needed for some biotech applications. In this sense, progress in this field has been marked by the utilization of high-throughput techniques to gain deep understanding of the molecular machinery controlling the physiology of these organisms, starting thus the Systems Biology era of fungi. Additionally, genetic engineering has been extensively applied to modify wellcharacterized promoters in order to construct new expression systems with enhanced performance under the conditions of interest. In this review, we discuss some aspects related to significant progress in the understating and engineering of fungi for biotechnological applications, with special focus on the construction of synthetic promoters and circuits in organisms relevant for industry. Different engineering approaches are shown, and their potential and limitations for the construction of complex synthetic circuits in these organisms are examined. Finally, we discuss the impact of engineered promoter architecture in the single-cell behavior of the system, an often-neglected relationship with a tremendous impact in the final performance of the process of interest. We expect to provide here some new directions to drive future research directed to the construction of high-performance, engineered fungal strains working as microbial cell factories.

  16. A Novel Evolutionary Engineering Design Approach for Mixed-Domain Systems

    DEFF Research Database (Denmark)

    Fan, Zhun; Hu, J.; Seo, K.

    2004-01-01

    to different or mixed physical domains, such as electrical, mechanical, hydraulic, pneumatic, thermal systems and/or a mixture of them. Two important tools are used in this approach, namely, bond graphs and genetic programming. Bond graphs are useful because they are domain independent, amenable to free......This paper presents an approach to engineering design of mixed-domain dynamic systems. The approach aims at system-level design and has two key features: first, it generates engineering designs that satisfy predefined specifications in an automatic manner; second, it can design systems belonging...... structural composition, and are efficient for classification and analysis, allowing rapid determination of various types of acceptability or feasibility of candidate designs. Genetic programming, on the other hand, is a powerful tool for open-ended topological search. To prevent the premature convergence...

  17. Influence of Underhood Flow on Engine Cooling Using 1-D And 3-D Approach

    Directory of Open Access Journals (Sweden)

    Bolehovský Ondřej

    2015-12-01

    Full Text Available This work deals with numerical simulation of complete cooling system of internal combustion engine (GT-SUITE, which also involves the simulation of flow in underhood using the computationally undemanding simulation. A detailed model of the internal combustion engine is extended to a cooling circuit model which is then coupled to a simplified underhood model which is created with the help of GT-COOL application as a 3-D model and afterwards transferred to a 1-D form. The approaches, one using 1-D solution of arrangement of the heat exchangers and the other 3-D approach using the underhood model, were investigated in two steady states corresponding to various vehicle speeds and engine load. These simulations have shown the inappropriateness of 1-D approach when solving the flow in the heat exchangers in the underhood and helped to explore a relatively undemanding method of flow simulation in the underhood, which enables to detect the interaction between the models of the cooling system and the internal combustion engine and the issue of arrangement of the heat exchangers in the underhood.

  18. Fundamentals of Materials Science and Engineering: An Integrated Approach, 2nd Edition

    Science.gov (United States)

    Callister, William D., Jr.

    2004-04-01

    This Second Edition of Fundamentals of Materials Science and Engineering continues to take an integrated approach to the topic organization. One specific structure, characteristic, or property type at a time is discussed for all three basic material types--metals, ceramics, and polymeric materials. This order of presentation allows for early introduction of non-metals and supports the engineer's role of choosing a material based on its characteristics. New copies of this text include a CD at no additional charge. The CD is an integral part of the text package and features animated software modules and the last five text chapters in .pdf format.

  19. Durable ideas in software engineering concepts, methods and approaches from my virtual toolbox

    CERN Document Server

    J Cusick, James

    2013-01-01

    ""Software Engineering now occupies a central place in the development of technology and in the advancement of the economy. From telecommunications to aerospace and from cash registers to medical imaging, software plays a vital and often decisive role in the successful accomplishment of a variety of projects. The creation of software requires a variety of techniques, tools, and especially, properly skilled engineers. This e-book focuses on core concepts and approaches that have proven useful to the author time and time again on many industry projects over a quarter century of research, develo

  20. Towards tailor-made oligosaccharides-chemo-enzymatic approaches by enzyme and substrate engineering.

    Science.gov (United States)

    Homann, Arne; Seibel, Jürgen

    2009-05-01

    Carbohydrate structures have been identified in eukaryotic and prokaryotic cells as glycoconjugates with communication skills. Their recently discussed role in various diseases has attracted high attention in the development of simple and convenient methods for oligosaccharide synthesis. In this review, recent approaches combining nature's power for the design of tailor made biocatalysts by enzyme engineering and substrate engineering will be presented. These strategies lead to highly efficient and selective glycosylation reactions. The introduced concept shall be a first step in the direction to a glycosylation toolbox which paves the way for the tailor-made synthesis of designed carbohydrate structures.

  1. A Novel Outreach to High School Students by Teaching Them the Engineering Skills in a Project-Based Approach

    Science.gov (United States)

    Asiabanpour, Bahram

    2010-01-01

    In this paper a novel outreach approach to high school students to familiarize them with engineering functions and methods is explained. In this approach students participated in a seven days research camp and learned many engineering skills and tools such as CAD solid modeling, finite element analysis, rapid prototyping, mechanical tests, team…

  2. An engineering approach to modelling, decision support and control for sustainable systems.

    Science.gov (United States)

    Day, W; Audsley, E; Frost, A R

    2008-02-12

    Engineering research and development contributes to the advance of sustainable agriculture both through innovative methods to manage and control processes, and through quantitative understanding of the operation of practical agricultural systems using decision models. This paper describes how an engineering approach, drawing on mathematical models of systems and processes, contributes new methods that support decision making at all levels from strategy and planning to tactics and real-time control. The ability to describe the system or process by a simple and robust mathematical model is critical, and the outputs range from guidance to policy makers on strategic decisions relating to land use, through intelligent decision support to farmers and on to real-time engineering control of specific processes. Precision in decision making leads to decreased use of inputs, less environmental emissions and enhanced profitability-all essential to sustainable systems.

  3. On the Brink of Shifting Paradigms, Molecular Systems Engineering Ethics Needs to Take a Proactive Approach.

    Science.gov (United States)

    Heidari, Raheleh; Elger, Bernice S; Stutzki, Ralf

    2016-01-01

    Molecular Systems Engineering (MSE) is a paradigm shift in both engineering and life sciences. While the field is still in its infancy the perspectives of MSE in revolutionising technology is promising. MSE will offer a wide range of applications in clinical, biotechnological and engineering fields while simultaneously posing serious questions on the ethical and societal aspects of such technology. The moral and societal aspects of MSE need systematic investigation from scientific and social perspectives. In a democratic setting, the societal outcomes of MSE's cutting-edge technology need to be consulted and influenced by society itself. For this purpose MSE needs inclusive public engagement strategies that bring together the public, ethicists, scientists and policy makers for optimum flow of information that maximizes the impact of public engagement. In this report we present an MSE consortium and its ethics framework for establishing a proactive approach in the study of the ethics of MSE technology.

  4. A Value-Based Business Approach to Product Line Software Engineering

    Directory of Open Access Journals (Sweden)

    Raman K. Agrawalla

    2009-08-01

    Full Text Available The present conceptual paper is an attempt to provide a Value-Based Business Approach (VBBA to product line software engineering. It argues that Product line software engineering should be seen as a system and considered as a means towards the end of appropriating more and more value for the business firm; contingent upon the fact that it provides value to customer and customer's customers operating its value creating system with agility, speed, economy and innovation; getting governed by the positive sum value creation outlook and guided by value- based management. With our value-based business triad, the product line engineering process can hope to achieve simultaneously value, variety and volume, product differentiation and cost leadership enabling the business firm to land on the virtuous value spiral.

  5. 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...

  6. COMPARISONS BETWEEN AND COMBINATIONS OF DIFFERENT APPROACHES TO ACCELERATE ENGINEERING PROJECTS

    Directory of Open Access Journals (Sweden)

    H. Steyn

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: In this article, traditional project management methods such as PERT and CPM, as well as fast-tracking and systems approaches, viz. concurrent engineering and critical chain, are reviewed with specific reference to their contribution to reducing the duration of the execution phase of engineering projects. Each of these techniques has some role to play in the acceleration of project execution. Combinations of approaches are evaluated by considering the potential of sets consisting of two different approaches each. While PERT and CPM approaches have been combined for many years in a technique called PERT/CPM, new combinations of approaches are discussed. Certain assumptions inherent to PERT and often wrong are not made by the critical chain approach.

    AFRIKAANSE OPSOMMING: In hierdie artikel word tradisionele projekbestuurbenaderings soos PERT en CPM asook projekversnelling en stelselbenaderings, naamlik gelyktydige ingenieurswese, en kritiekeketting-ondersoek met betrekking tot die bydrae wat elk tot die versnelling van die uitvoeringsfase van ingenieursprojekte kan lewer. Elk van hierdie benaderings kan ‘n spesifieke bydrae tot die versnelling van projekte lewer. Kombinasies, elk bestaande uit twee verskillende benaderings, word geëvalueer. Terwyl PERT en CPM reeds baie jare lank in kombinasie gebruik word, word nuwe kombinasies ook hier bespreek. Sekere aannames inherent aan die PERT-benadering is dikwels foutief. Hierdie aannames word nie deur die kritieke-ketting-benadering gemaak nie.

  7. Development of field programmable gate array-based reactor trip functions using systems engineering approach

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jae Cheon; Ahmed, Ibrahim [Nuclear Power Plant Engineering, KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2016-08-15

    Design engineering process for field programmable gate array (FPGA)-based reactor trip functions are developed in this work. The process discussed in this work is based on the systems engineering approach. The overall design process is effectively implemented by combining with design and implementation processes. It transforms its overall development process from traditional V-model to Y-model. This approach gives the benefit of concurrent engineering of design work with software implementation. As a result, it reduces development time and effort. The design engineering process consisted of five activities, which are performed and discussed: needs/systems analysis; requirement analysis; functional analysis; design synthesis; and design verification and validation. Those activities are used to develop FPGA-based reactor bistable trip functions that trigger reactor trip when the process input value exceeds the setpoint. To implement design synthesis effectively, a model-based design technique is implied. The finite-state machine with data path structural modeling technique together with very high speed integrated circuit hardware description language and the Aldec Active-HDL tool are used to design, model, and verify the reactor bistable trip functions for nuclear power plants.

  8. Systematic Approach to Training for System Engineers in Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Jeong-keun [Korea Hydro and Nuclear Power Co., Ulsan (Korea, Republic of)

    2015-10-15

    In my paper, comprehensive preparations, tangible applications, and final establishments of training for system engineers are described using practical materials in KHNP. The purpose of this paper is to formulate SAT based training in KHNP, especially for system engineers. Hence, to achieve this goal, over one year study was performed considering voluminous materials and working experiences. Through the process, SAT based training package for system engineers was finished, in the end. In terms of training in NPPs, SAT methodology is the unwavering trend in South Korea since NPPs export to UAE. Therefore, materialization of SAT based training for system engineers from the origin of SAT to the finalization of SAT should not be overlooked. A variety of accident preventive approaches have been adopted since the first commercial NPP operation in Calder Hall, United Kingdom. Among diverse event preventive ways, training has played an important role for the improvement of NPPs reliability and safety. This is reason why nuclear industry in every country has established and maintained own training institutes and methods. Since the Three Mile Island (TMI) accident, United States Nuclear Regulatory Commission (USNRC) recommended many betterment plans to US nuclear industry for the elevation of NPPs safety. In the suggested considerations, systematic approach to training, so called SAT appeared in the world. Basically, SAT is composed of five stages, what is called ADDIE. Hence, through ADDIE process, holistic and trustworthy training could be realized in the actual NPPs operation and maintenance. For this reason, SAT is the representative training methodology in the US nuclear business.

  9. Hybrid Kalman Filter: A New Approach for Aircraft Engine In-Flight Diagnostics

    Science.gov (United States)

    Kobayashi, Takahisa; Simon, Donald L.

    2006-01-01

    In this paper, a uniquely structured Kalman filter is developed for its application to in-flight diagnostics of aircraft gas turbine engines. The Kalman filter is a hybrid of a nonlinear on-board engine model (OBEM) and piecewise linear models. The utilization of the nonlinear OBEM allows the reference health baseline of the in-flight diagnostic system to be updated to the degraded health condition of the engines through a relatively simple process. Through this health baseline update, the effectiveness of the in-flight diagnostic algorithm can be maintained as the health of the engine degrades over time. Another significant aspect of the hybrid Kalman filter methodology is its capability to take advantage of conventional linear and nonlinear Kalman filter approaches. Based on the hybrid Kalman filter, an in-flight fault detection system is developed, and its diagnostic capability is evaluated in a simulation environment. Through the evaluation, the suitability of the hybrid Kalman filter technique for aircraft engine in-flight diagnostics is demonstrated.

  10. A Model-Based Anomaly Detection Approach for Analyzing Streaming Aircraft Engine Measurement Data

    Science.gov (United States)

    Simon, Donald L.; Rinehart, Aidan Walker

    2015-01-01

    This paper presents a model-based anomaly detection architecture designed for analyzing streaming transient aircraft engine measurement data. The technique calculates and monitors residuals between sensed engine outputs and model predicted outputs for anomaly detection purposes. Pivotal to the performance of this technique is the ability to construct a model that accurately reflects the nominal operating performance of the engine. The dynamic model applied in the architecture is a piecewise linear design comprising steady-state trim points and dynamic state space matrices. A simple curve-fitting technique for updating the model trim point information based on steadystate information extracted from available nominal engine measurement data is presented. Results from the application of the model-based approach for processing actual engine test data are shown. These include both nominal fault-free test case data and seeded fault test case data. The results indicate that the updates applied to improve the model trim point information also improve anomaly detection performance. Recommendations for follow-on enhancements to the technique are also presented and discussed.

  11. Science, technology, engineering, mathematics (STEM) as mathematics learning approach in 21st century

    Science.gov (United States)

    Milaturrahmah, Naila; Mardiyana, Pramudya, Ikrar

    2017-08-01

    This 21st century demands competent human resources in science, technology, engineering design and mathematics so that education is expected to integrate the four disciplines. This paper aims to describe the importance of STEM as mathematics learning approach in Indonesia in the 21st century. This paper uses a descriptive analysis research method, and the method reveals that STEM education growing in developed countries today can be a framework for innovation mathematics in Indonesia in the 21st century. STEM education integrate understanding of science, math skills, and the available technology with the ability to perform engineering design process. Implementation of mathematics learning with STEM approach makes graduates trained in using of mathematics knowledge that they have to create innovative products that are able to solve the problems that exist in society.

  12. Role-play and the Industrial Revolution: an STS approach to the teaching of steam engines

    Science.gov (United States)

    Sabka, Diego; Pereira de Pereira, Alexsandro; Lima Junior, Paulo

    2016-11-01

    Role-play is an interesting, although underexplored, way of teaching physics in high school. This paper presents a science-technology-society (STS) approach to the teaching of heat engines based on a role-play of the Industrial Revolution. Enacting the role-play, students are presented not only to scientific concepts, but also to the social and technological controversies of industrial development.

  13. The limitations of the reverse-engineering approach to cognitive modeling.

    Science.gov (United States)

    Rueckl, Jay G

    2012-10-01

    Frost's critique reveals the limitations of the reverse-engineering approach to cognitive modeling--the style of psychological explanation in which a stipulated internal organization (in the form of a computational mechanism) explains a relatively narrow set of phenomena. An alternative is to view organization as both the explanation for some phenomena and a phenomenon to be explained. This move poses new and interesting theoretical challenges for theories of word reading.

  14. Conceptual framework and system house approach to designing search engine controversy

    Directory of Open Access Journals (Sweden)

    В.В. Шкурко

    2006-04-01

    Full Text Available  Conceptual Principles and System Engineer Principles Approach for Project System to Search for Contradictions There is outlined a range of tasks which are necessary to be solved for the organization of technology for the computer support of logic- linguistic professional findings in the legislative documents. There is shown a model of the informational process to carry out the professional findings, is proposed an information elements interworking, is worked out a model of the contradictions base.

  15. Model-driven engineering approach to design and implementation of robot control system

    OpenAIRE

    Trojanek, Piotr

    2013-01-01

    In this paper we apply a model-driven engineering approach to designing domain-specific solutions for robot control system development. We present a case study of the complete process, including identification of the domain meta-model, graphical notation definition and source code generation for subsumption architecture -- a well-known example of robot control architecture. Our goal is to show that both the definition of the robot-control architecture and its supporting tools fits well into t...

  16. Model-driven engineering approach to design and implementation of robot control system

    OpenAIRE

    Trojanek, Piotr

    2013-01-01

    In this paper we apply a model-driven engineering approach to designing domain-specific solutions for robot control system development. We present a case study of the complete process, including identification of the domain meta-model, graphical notation definition and source code generation for subsumption architecture -- a well-known example of robot control architecture. Our goal is to show that both the definition of the robot-control architecture and its supporting tools fits well into t...

  17. A multi-criteria optimization and decision-making approach for improvement of food engineering processes

    Directory of Open Access Journals (Sweden)

    Alik Abakarov

    2013-04-01

    Full Text Available The objective of this study was to propose a multi-criteria optimization and decision-making technique to solve food engineering problems. This technique was demonstrated using experimental data obtained on osmotic dehydration of carrot cubes in a sodium chloride solution. The Aggregating Functions Approach, the Adaptive Random Search Algorithm, and the Penalty Functions Approach were used in this study to compute the initial set of non-dominated or Pareto-optimal solutions. Multiple non-linear regression analysis was performed on a set of experimental data in order to obtain particular multi-objective functions (responses, namely water loss, solute gain, rehydration ratio, three different colour criteria of rehydrated product, and sensory evaluation (organoleptic quality. Two multi-criteria decision-making approaches, the Analytic Hierarchy Process (AHP and the Tabular Method (TM, were used simultaneously to choose the best alternative among the set of non-dominated solutions. The multi-criteria optimization and decision-making technique proposed in this study can facilitate the assessment of criteria weights, giving rise to a fairer, more consistent, and adequate final compromised solution or food process. This technique can be useful to food scientists in research and education, as well as to engineers involved in the improvement of a variety of food engineering processes.

  18. Learning motor control in the upright position: a mechanical engineering approach.

    Science.gov (United States)

    Major, R E; Johnson, G R; Butler, P B

    2001-01-01

    Motor control problems that result from damage to the central nervous system can make it difficult to learn functional activities. Although several therapeutic approaches attempt to address such problems there is little evidence of their efficacy. Targeted Training is a new approach, based on a biomechanical analysis of the problem, which usually relies on specifically designed equipment. This paper describes the underlying theory, the development of functional specifications, the translation of these specifications into an engineering design and the clinical results of applying the equipment. The promotion of head and trunk control provides an example of the process.

  19. Engineering geological mapping in Wallonia (Belgium) : present state and recent computerized approach

    Science.gov (United States)

    Delvoie, S.; Radu, J.-P.; Ruthy, I.; Charlier, R.

    2012-04-01

    An engineering geological map can be defined as a geological map with a generalized representation of all the components of a geological environment which are strongly required for spatial planning, design, construction and maintenance of civil engineering buildings. In Wallonia (Belgium) 24 engineering geological maps have been developed between the 70s and the 90s at 1/5,000 or 1/10,000 scale covering some areas of the most industrialized and urbanized cities (Liège, Charleroi and Mons). They were based on soil and subsoil data point (boring, drilling, penetration test, geophysical test, outcrop…). Some displayed data present the depth (with isoheights) or the thickness (with isopachs) of the different subsoil layers up to about 50 m depth. Information about geomechanical properties of each subsoil layer, useful for engineers and urban planners, is also synthesized. However, these maps were built up only on paper and progressively needed to be updated with new soil and subsoil data. The Public Service of Wallonia and the University of Liège have recently initiated a study to evaluate the feasibility to develop engineering geological mapping with a computerized approach. Numerous and various data (about soil and subsoil) are stored into a georelational database (the geotechnical database - using Access, Microsoft®). All the data are geographically referenced. The database is linked to a GIS project (using ArcGIS, ESRI®). Both the database and GIS project consist of a powerful tool for spatial data management and analysis. This approach involves a methodology using interpolation methods to update the previous maps and to extent the coverage to new areas. The location (x, y, z) of each subsoil layer is then computed from data point. The geomechanical data of these layers are synthesized in an explanatory booklet joined to maps.

  20. On a Vision to Educating Students in Sustainability and Design—The James Madison University School of Engineering Approach

    Directory of Open Access Journals (Sweden)

    Olga Pierrakos

    2011-12-01

    Full Text Available In order for our future engineers to be able to work toward a sustainable future, they must be versed not only in sustainable engineering but also in engineering design. An engineering education must train our future engineers to think flexibly and to be adaptive, as it is unlikely that their future will have them working in one domain. They must, instead, be versatilists. The School of Engineering at James Madison University has been developed from the ground up to provide this engineering training with an emphasis on engineering design, systems thinking, and sustainability. Neither design nor sustainability are mutually exclusive, and consequently, an education focusing on design and sustainability must integrate these topics, teaching students to follow a sustainable design process. This is the goal of the James Madison University School of Engineering. In this paper, we present our approach to curricular integration of design and sustainability as well as the pedagogical approaches used throughout the curriculum. We do not mean to present the School’s model as an all or nothing approach consisting of dependent elements, but instead as a collection of independent approaches, of which one or more may be appropriate at another university.

  1. How should we foster the professional integrity of engineers in Japan? A pride-based approach.

    Science.gov (United States)

    Iseda, Tetsuji

    2008-06-01

    I discuss the predicament that engineering-ethics education in Japan now faces and propose a solution to this. The predicament is professional motivation, i.e., the problem of how to motivate engineering students to maintain their professional integrity. The special professional responsibilities of engineers are often explained either as an implicit social contract between the profession and society (the "social-contract" view), or as requirements for membership in the profession (the "membership-requirement" view). However, there are empirical data that suggest that such views will not do in Japan, and this is the predicament that confronts us. In this country, the profession of engineering did not exist 10 years ago and is still quite underdeveloped. Engineers in this country do not have privileges, high income, or high social status. Under such conditions, neither the social-contract view nor the membership-requirement view is convincing. As an alternative approach that might work in Japan, I propose a pride-based view. The notion of pride has been analyzed in the virtue-ethics literature, but the full potential of this notion has not been explored. Unlike other kinds of pride, professional pride can directly benefit the general public by motivating engineers to do excellent work even without social rewards, since being proud of themselves is already a reward. My proposal is to foster a particular kind of professional pride associated with the importance of professional services in society, as the motivational basis for professional integrity. There is evidence to suggest that this model works.

  2. Spatiotemporal Characterization of Extracellular Matrix Microstructures in Engineered Tissue: A Whole-Field Spectroscopic Imaging Approach.

    Science.gov (United States)

    Xu, Zhengbin; Ozcelikkale, Altug; Kim, Young L; Han, Bumsoo

    2013-02-01

    Quality and functionality of engineered tissues are closely related to the microstructures and integrity of their extracellular matrix (ECM). However, currently available methods for characterizing ECM structures are often labor-intensive, destructive, and limited to a small fraction of the total area. These methods are also inappropriate for assessing temporal variations in ECM structures. In this study, to overcome these limitations and challenges, we propose an elastic light scattering approach to spatiotemporally assess ECM microstructures in a relatively large area in a nondestructive manner. To demonstrate its feasibility, we analyze spectroscopic imaging data obtained from acellular collagen scaffolds and dermal equivalents as model ECM structures. For spatial characterization, acellular scaffolds are examined after a freeze/thaw process mimicking a cryopreservation procedure to quantify freezing-induced structural changes in the collagen matrix. We further analyze spatial and temporal changes in ECM structures during cell-driven compaction in dermal equivalents. The results show that spectral dependence of light elastically backscattered from engineered tissue is sensitively associated with alterations in ECM microstructures. In particular, a spectral decay rate over the wavelength can serve as an indicator for the pore size changes in ECM structures, which are at nanometer scale. A decrease in the spectral decay rate suggests enlarged pore sizes of ECM structures. The combination of this approach with a whole-field imaging platform further allows visualization of spatial heterogeneity of EMC microstructures in engineered tissues. This demonstrates the feasibility of the proposed method that nano- and micrometer scale alteration of the ECM structure can be detected and visualized at a whole-field level. Thus, we envision that this spectroscopic imaging approach could potentially serve as an effective characterization tool to nondestructively, accurately

  3. Building international experiences into an engineering curriculum - a design project-based approach

    Science.gov (United States)

    Maldonado, Victor; Castillo, Luciano; Carbajal, Gerardo; Hajela, Prabhat

    2014-07-01

    This paper is a descriptive account of how short-term international and multicultural experiences can be integrated into early design experiences in an aerospace engineering curriculum. Such approaches are considered as important not only in fostering a student's interest in the engineering curriculum, but also exposing them to a multicultural setting that they are likely to encounter in their professional careers. In the broader sense, this programme is described as a model that can be duplicated in other engineering disciplines as a first-year experience. In this study, undergraduate students from Rensselaer Polytechnic Institute (RPI) and Universidad del Turabo (UT) in Puerto Rico collaborated on a substantial design project consisting of designing, fabricating, and flight-testing radio-controlled model aircraft as a capstone experience in a semester-long course on Fundamentals of Flight. The two-week long experience in Puerto Rico was organised into academic and cultural components designed with the following objectives: (i) to integrate students in a multicultural team-based academic and social environment, (ii) to practise team-building skills and develop students' critical thinking and analytical skills, and finally (iii) to excite students about their engineering major through practical applications of aeronautics and help them decide if it is a right fit for them.

  4. Determination of knock characteristics in spark ignition engines: an approach based on ensemble empirical mode decomposition

    Science.gov (United States)

    Li, Ning; Yang, Jianguo; Zhou, Rui; Liang, Caiping

    2016-04-01

    Knock is one of the major constraints to improve the performance and thermal efficiency of spark ignition (SI) engines. It can also result in severe permanent engine damage under certain operating conditions. Based on the ensemble empirical mode decomposition (EEMD), this paper proposes a new approach to determine the knock characteristics in SI engines. By adding a uniformly distributed and finite white Gaussian noise, the EEMD can preserve signal continuity in different scales and therefore alleviates the mode-mixing problem occurring in the classic empirical mode decomposition (EMD). The feasibilities of applying the EEMD to detect the knock signatures of a test SI engine via the pressure signal measured from combustion chamber and the vibration signal measured from cylinder head are investigated. Experimental results show that the EEMD-based method is able to detect the knock signatures from both the pressure signal and vibration signal, even in initial stage of knock. Finally, by comparing the application results with those obtained by short-time Fourier transform (STFT), Wigner-Ville distribution (WVD) and discrete wavelet transform (DWT), the superiority of the EEMD method in determining knock characteristics is demonstrated.

  5. Deformation and fracture of solid-state materials field theoretical approach and engineering applications

    CERN Document Server

    Yoshida, Sanichiro

    2015-01-01

    This book introduces a comprehensive theory of deformation and fracture to engineers and applied scientists. The author explains the gist of local symmetry (gauge invariance) intuitively so that engineers and applied physicists can digest it easily, rather than describing physical or mathematical details of the principle. Applications of the theory to practical engineering are also described, such as nondestructive testing, in particular, with the use of an optical interferometric technique called ESPI (Electronic Speckle-Pattern Interferometry). The book provides information on how to apply physical concepts to engineering applications. This book also: ·         Describes a highly original way to reveal loading hysteresis of a given specimen ·         Presents a fundamentally new approach to deformation and fracture, which offers potential for new applications ·         Introduces the unique application of Electric Speckle-Pattern Interferometry—reading fringe patterns to connect...

  6. A Model-Based Approach to Engineering Behavior of Complex Aerospace Systems

    Science.gov (United States)

    Ingham, Michel; Day, John; Donahue, Kenneth; Kadesch, Alex; Kennedy, Andrew; Khan, Mohammed Omair; Post, Ethan; Standley, Shaun

    2012-01-01

    One of the most challenging yet poorly defined aspects of engineering a complex aerospace system is behavior engineering, including definition, specification, design, implementation, and verification and validation of the system's behaviors. This is especially true for behaviors of highly autonomous and intelligent systems. Behavior engineering is more of an art than a science. As a process it is generally ad-hoc, poorly specified, and inconsistently applied from one project to the next. It uses largely informal representations, and results in system behavior being documented in a wide variety of disparate documents. To address this problem, JPL has undertaken a pilot project to apply its institutional capabilities in Model-Based Systems Engineering to the challenge of specifying complex spacecraft system behavior. This paper describes the results of the work in progress on this project. In particular, we discuss our approach to modeling spacecraft behavior including 1) requirements and design flowdown from system-level to subsystem-level, 2) patterns for behavior decomposition, 3) allocation of behaviors to physical elements in the system, and 4) patterns for capturing V&V activities associated with behavioral requirements. We provide examples of interesting behavior specification patterns, and discuss findings from the pilot project.

  7. SOFTWARE BASED APPROACH FOR CLASSROOM TEACHING OF ELECTRICAL ENGINEERING COURSES: A CASE STUDY

    Directory of Open Access Journals (Sweden)

    Hemant Mehar

    2015-06-01

    Full Text Available Electrical engineering concepts are abstract in nature and difficult to explain using conventional teaching tools. The use of software in teaching holds the potential in providing better learning support as these tools can provide visual representations of complex circuits operation and waveforms for enhanced concept and procedural learning in power electronics. The software packages available for simulation of power electronic circuits include MATLAB, PSPICE and PSIM. In this study the author takes an example of an AC voltage controller to explain the software based teaching approach. The author used two software based simulation tools to explain the AC voltage controller concept and compare the software based approach with the blackboard and power point presentation based technique. Results of different approaches are compared in the last session of this paper, so it is helpful for the faculty of electrical engineering to find the various applications of MATLAB, SIMULINK and PSIM in teaching. Overall students find the simulation approach is helpful for their learning.

  8. Maximizing cartilage formation and integration via a trajectory-based tissue engineering approach.

    Science.gov (United States)

    Fisher, Matthew B; Henning, Elizabeth A; Söegaard, Nicole B; Dodge, George R; Steinberg, David R; Mauck, Robert L

    2014-02-01

    Given the limitations of current surgical approaches to treat articular cartilage injuries, tissue engineering (TE) approaches have been aggressively pursued. Despite reproduction of key mechanical attributes of native tissue, the ability of TE cartilage constructs to integrate with native tissue must also be optimized for clinical success. In this paper, we propose a "trajectory-based" tissue engineering (TB-TE) approach, based on the hypothesis that time-dependent increases in construct maturation in-vitro prior to implantation (i.e. positive rates) may provide a reliable predictor of in-vivo success. As an example TE system, we utilized hyaluronic acid hydrogels laden with mesenchymal stem cells. We first modeled the maturation of these constructs in-vitro to capture time-dependent changes. We then performed a sensitivity analysis of the model to optimize the timing and amount of data collection. Finally, we showed that integration to cartilage in-vitro is not correlated to the maturation state of TE constructs, but rather their maturation rate, providing a proof-of-concept for the use of TB-TE to enhance treatment outcomes following cartilage injury. This new approach challenges the traditional TE paradigm of matching only native state parameters of maturity and emphasizes the importance of also establishing an in-vitro trajectory in constructs in order to improve the chance of in-vivo success.

  9. An Integrated Approach for Aircraft Engine Performance Estimation and Fault Diagnostics

    Science.gov (United States)

    imon, Donald L.; Armstrong, Jeffrey B.

    2012-01-01

    A Kalman filter-based approach for integrated on-line aircraft engine performance estimation and gas path fault diagnostics is presented. This technique is specifically designed for underdetermined estimation problems where there are more unknown system parameters representing deterioration and faults than available sensor measurements. A previously developed methodology is applied to optimally design a Kalman filter to estimate a vector of tuning parameters, appropriately sized to enable estimation. The estimated tuning parameters can then be transformed into a larger vector of health parameters representing system performance deterioration and fault effects. The results of this study show that basing fault isolation decisions solely on the estimated health parameter vector does not provide ideal results. Furthermore, expanding the number of the health parameters to address additional gas path faults causes a decrease in the estimation accuracy of those health parameters representative of turbomachinery performance deterioration. However, improved fault isolation performance is demonstrated through direct analysis of the estimated tuning parameters produced by the Kalman filter. This was found to provide equivalent or superior accuracy compared to the conventional fault isolation approach based on the analysis of sensed engine outputs, while simplifying online implementation requirements. Results from the application of these techniques to an aircraft engine simulation are presented and discussed.

  10. Library selection and directed evolution approaches to engineering targeted viral vectors.

    Science.gov (United States)

    Jang, Jae-Hyung; Lim, Kwang-il; Schaffer, David V

    2007-10-15

    Gene therapy, to delivery of genetic material to a patient for therapeutic benefit, has significant promise for translating basic knowledge of disease mechanism into biomedical treatments. The clinical development of the field has been slowed, however, by the need for improvements in the properties and capabilities of gene delivery vehicles. Vehicles based on viruses offer the potential for efficient gene delivery, but because viruses did not evolve to serve human therapeutic needs, many of their properties require significant improvement, including their safety, efficiency, and capacity for targeted gene delivery. Since viruses are highly complex biological entities, engineering such properties at the molecular level can be challenging. However, there has been significant progress in developing approaches that mimic the mechanisms by which viruses arose in the first place. In particular, library-based selection, the generation of one diverse genetic library and selection for new properties, and directed evolution, based on the multiple rounds of library generation and selection for iterative improvement of function, have strong potential in engineering novel properties into these complex biomolecular assemblies. This review will discuss progress in the application of peptide display, library selection, and directed evolution technologies toward engineering vectors based on retrovirus, adeno-associated virus, and adenovirus that are capable of targeted delivery to specific cell types. In addition to creating biomedically useful products, these approaches have future potential to yield novel insights into viral structure-function relationships. Copyright 2007 Wiley Periodicals, Inc.

  11. Towards the design of 3D multiscale instructive tissue engineering constructs: Current approaches and trends.

    Science.gov (United States)

    Oliveira, Sara M; Reis, Rui L; Mano, João F

    2015-11-01

    The design of 3D constructs with adequate properties to instruct and guide cells both in vitro and in vivo is one of the major focuses of tissue engineering. Successful tissue regeneration depends on the favorable crosstalk between the supporting structure, the cells and the host tissue so that a balanced matrix production and degradation are achieved. Herein, the major occurring events and players in normal and regenerative tissue are overviewed. These have been inspiring the selection or synthesis of instructive cues to include into the 3D constructs. We further highlight the importance of a multiscale perception of the range of features that can be included on the biomimetic structures. Lastly, we focus on the current and developing tissue-engineering approaches for the preparation of such 3D constructs: top-down, bottom-up and integrative. Bottom-up and integrative approaches present a higher potential for the design of tissue engineering devices with multiscale features and higher biochemical control than top-down strategies, and are the main focus of this review. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Developing a Standard Approach to the Value Engineering Process for the Civil Engineering Industry: a Theoretical, Case Study and Industry Perspective.

    OpenAIRE

    Mitchell, Charles Anthony

    2013-01-01

    The original Value Engineering process developed in North America in the late 1940‟s, was primarily based on functional analysis. However; the North American Value Engineering process was not adopted in Europe. Instead various mixed methods were assembled under the umbrella term of Value Management. Nowadays there is much debate about what Value Engineering is and how is it defined? This question arises in part due to there being no standard approach in Europe as a whole in undertaking ValueM...

  13. Neural network approach for modification and fitting of digitized data in reverse engineering

    Institute of Scientific and Technical Information of China (English)

    JU Hua(鞠华); WANG Wen(王文); XIE Jin (谢金); CHEN Zi-chen(陈子辰)

    2004-01-01

    Reverse engineering in the manufacturing field is a process in which the digitized data are obtained from an existing object model or a part of it, and then the CAD model is reconstructed. This paper presents an RBF neural network approach to modify and fit the digitized data. The centers for the RBF are selected by using the orthogonal least squares learning algorithm. A mathematically known surface is used for generating a number of samples for training the networks. The trained networks then generated a number of new points which were compared with the calculating points from the equations. Moreover, a series of practice digitizing curves are used to test the approach. The results showed that this approach is effective in modifying and fitting digitized data and generating data points to reconstruct the surface model.

  14. Neural network approach for modification and fitting of digitized data in reverse engineering~

    Institute of Scientific and Technical Information of China (English)

    鞠华; 王文; 谢金; 陈子辰

    2004-01-01

    Reverse engineering in the manufacturing field is a process in which the digitized data are obtained from an existing object model or a part of it, and then the CAD model is reconstructed. This paper presents an RBF neural network approach to modify and fit the digitized data. The centers for the RBF are selected by using the orthogonal least squares learning algorithm. A mathematically known surface is used for generating a number of samples for training the networks. The trained networks then generated a number of new points which were compared with the calculating points from the equations. Moreover, a series of practice digitizing curves are used to test the approach. The results showed that this approach is effective in modifying and fitting digitized data and generating data points to reconstruct the surface model.

  15. Strengthening the Link between Theory and Practice in Teaching Design Engineering: An Empirical Study on a New Approach

    Science.gov (United States)

    Tempelman, E.; Pilot, A.

    2011-01-01

    In 2007, the Faculty of Industrial Design Engineering of the Delft University of Technology introduced a new bachelor program. Based on theories of learning and instruction three design principles were used to develop an approach that aims to make it easier for students to bridge the gap between theoretical design engineering courses and practical…

  16. Strengthening the Link between Theory and Practice in Teaching Design Engineering: An Empirical Study on a New Approach

    Science.gov (United States)

    Tempelman, E.; Pilot, A.

    2011-01-01

    In 2007, the Faculty of Industrial Design Engineering of the Delft University of Technology introduced a new bachelor program. Based on theories of learning and instruction three design principles were used to develop an approach that aims to make it easier for students to bridge the gap between theoretical design engineering courses and practical…

  17. Providing Formative Assessment to Students Solving Multipath Engineering Problems with Complex Arrangements of Interacting Parts: An Intelligent Tutor Approach

    Science.gov (United States)

    Steif, Paul S.; Fu, Luoting; Kara, Levent Burak

    2016-01-01

    Problems faced by engineering students involve multiple pathways to solution. Students rarely receive effective formative feedback on handwritten homework. This paper examines the potential for computer-based formative assessment of student solutions to multipath engineering problems. In particular, an intelligent tutor approach is adopted and…

  18. Genome-wide analytical approaches for reverse metabolic engineering of industrially relevant phenotypes in yeast

    Science.gov (United States)

    Oud, Bart; Maris, Antonius J A; Daran, Jean-Marc; Pronk, Jack T

    2012-01-01

    Successful reverse engineering of mutants that have been obtained by nontargeted strain improvement has long presented a major challenge in yeast biotechnology. This paper reviews the use of genome-wide approaches for analysis of Saccharomyces cerevisiae strains originating from evolutionary engineering or random mutagenesis. On the basis of an evaluation of the strengths and weaknesses of different methods, we conclude that for the initial identification of relevant genetic changes, whole genome sequencing is superior to other analytical techniques, such as transcriptome, metabolome, proteome, or array-based genome analysis. Key advantages of this technique over gene expression analysis include the independency of genome sequences on experimental context and the possibility to directly and precisely reproduce the identified changes in naive strains. The predictive value of genome-wide analysis of strains with industrially relevant characteristics can be further improved by classical genetics or simultaneous analysis of strains derived from parallel, independent strain improvement lineages. PMID:22152095

  19. Software engineering techniques applied to agricultural systems an object-oriented and UML approach

    CERN Document Server

    Papajorgji, Petraq J

    2014-01-01

    Software Engineering Techniques Applied to Agricultural Systems presents cutting-edge software engineering techniques for designing and implementing better agricultural software systems based on the object-oriented paradigm and the Unified Modeling Language (UML). The focus is on the presentation of  rigorous step-by-step approaches for modeling flexible agricultural and environmental systems, starting with a conceptual diagram representing elements of the system and their relationships. Furthermore, diagrams such as sequential and collaboration diagrams are used to explain the dynamic and static aspects of the software system.    This second edition includes: a new chapter on Object Constraint Language (OCL), a new section dedicated to the Model-VIEW-Controller (MVC) design pattern, new chapters presenting details of two MDA-based tools – the Virtual Enterprise and Olivia Nova, and a new chapter with exercises on conceptual modeling.  It may be highly useful to undergraduate and graduate students as t...

  20. Non-Genetic Engineering Approaches for Isolating and Generating Novel Yeasts for Industrial Applications

    Science.gov (United States)

    Chambers, P. J.; Bellon, J. R.; Schmidt, S. A.; Varela, C.; Pretorius, I. S.

    Generating novel yeast strains for industrial applications should be quite straightforward; after all, research into the genetics, biochemistry and physiology of Baker's Yeast, Saccharomyces cerevisiae, has paved the way for many advances in the modern biological sciences. We probably know more about this humble eukaryote than any other, and it is the most tractable of organisms for manipulation using modern genetic engineering approaches. In many countries, however, there are restrictions on the use of genetically-modified organisms (GMOs), particularly in foods and beverages, and the level of consumer acceptance of GMOs is, at best, variable. Thus, many researchers working with industrial yeasts use genetic engineering techniques primarily as research tools, and strain development continues to rely on non-GM technologies. This chapter explores the non-GM tools and strategies available to such researchers.

  1. A Neural Network Approach on Reverse Engineering Surface Reasoning in the Manufacturing Field

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper applied the neural network technology to surfacereasoning in reverse engineering and established the neural network computation model. One of the main advantages of reasoning solid surface using neural network is that no knowledge about surface is needed, and the limited measured points on the surface will do sufficiently. This paper listed the related reasoning cases, including the elementary analytical surfaces and freeform surfaces, discussed the various issues occurring during reasoning process and proved the feasibility and efficiency of this approach from theory and practical computing cases. The results show that a neural network is an excellent aided analysis means for surface reasoning in reversing engineering and possesses practical use for the surface that is complex, incomplete and partially worn-out or damaged.

  2. Non-viral approaches for direct conversion into mesenchymal cell types: Potential application in tissue engineering.

    Science.gov (United States)

    Lee, Eun-Seo; Kim, Seung Hyun L; Lee, Hwajin; Hwang, Nathaniel S

    2016-05-01

    Acquiring adequate number of cells is one of the crucial factors to apply tissue engineering strategies in order to recover critical-sized defects. While the reprogramming technology used for inducing pluripotent stem cells (iPSCs) opened up a direct path for generating pluripotent stem cells, a direct conversion strategy may provide another possibility to obtain desired cells for tissue engineering. In order to convert a somatic cell into any other cell type, diverse approaches have been investigated. Conspicuously, in contrast to traditional viral transduction method, non-viral delivery of conversion factors has the merit of lowering immune responses and provides safer genetic manipulation, thus revolutionizing the generation of directly converted cells and its application in therapeutics. In addition, applying various microenvironmental modulations have potential to ameliorate the conversion of somatic cells into different lineages. In this review, we discuss the recent progress in direct conversion technologies, specifically focusing on generating mesenchymal cell types. © 2016 Wiley Periodicals, Inc.

  3. Growth factor delivery-based tissue engineering: general approaches and a review of recent developments.

    Science.gov (United States)

    Lee, Kangwon; Silva, Eduardo A; Mooney, David J

    2011-02-06

    The identification and production of recombinant morphogens and growth factors that play key roles in tissue regeneration have generated much enthusiasm and numerous clinical trials, but the results of many of these trials have been largely disappointing. Interestingly, the trials that have shown benefit all contain a common denominator, the presence of a material carrier, suggesting strongly that spatio-temporal control over the location and bioactivity of factors after introduction into the body is crucial to achieve tangible therapeutic effect. Sophisticated materials systems that regulate the biological presentation of growth factors represent an attractive new generation of therapeutic agents for the treatment of a wide variety of diseases. This review provides an overview of growth factor delivery in tissue engineering. Certain fundamental issues and design strategies relevant to the material carriers that are being actively pursued to address specific technical objectives are discussed. Recent progress highlights the importance of materials science and engineering in growth factor delivery approaches to regenerative medicine.

  4. Genome-wide analytical approaches for reverse metabolic engineering of industrially relevant phenotypes in yeast.

    Science.gov (United States)

    Oud, Bart; van Maris, Antonius J A; Daran, Jean-Marc; Pronk, Jack T

    2012-03-01

    Successful reverse engineering of mutants that have been obtained by nontargeted strain improvement has long presented a major challenge in yeast biotechnology. This paper reviews the use of genome-wide approaches for analysis of Saccharomyces cerevisiae strains originating from evolutionary engineering or random mutagenesis. On the basis of an evaluation of the strengths and weaknesses of different methods, we conclude that for the initial identification of relevant genetic changes, whole genome sequencing is superior to other analytical techniques, such as transcriptome, metabolome, proteome, or array-based genome analysis. Key advantages of this technique over gene expression analysis include the independency of genome sequences on experimental context and the possibility to directly and precisely reproduce the identified changes in naive strains. The predictive value of genome-wide analysis of strains with industrially relevant characteristics can be further improved by classical genetics or simultaneous analysis of strains derived from parallel, independent strain improvement lineages.

  5. A structured approach for the engineering of biochemical network models, illustrated for signalling pathways.

    Science.gov (United States)

    Breitling, Rainer; Gilbert, David; Heiner, Monika; Orton, Richard

    2008-09-01

    Quantitative models of biochemical networks (signal transduction cascades, metabolic pathways, gene regulatory circuits) are a central component of modern systems biology. Building and managing these complex models is a major challenge that can benefit from the application of formal methods adopted from theoretical computing science. Here we provide a general introduction to the field of formal modelling, which emphasizes the intuitive biochemical basis of the modelling process, but is also accessible for an audience with a background in computing science and/or model engineering. We show how signal transduction cascades can be modelled in a modular fashion, using both a qualitative approach--qualitative Petri nets, and quantitative approaches--continuous Petri nets and ordinary differential equations (ODEs). We review the major elementary building blocks of a cellular signalling model, discuss which critical design decisions have to be made during model building, and present a number of novel computational tools that can help to explore alternative modular models in an easy and intuitive manner. These tools, which are based on Petri net theory, offer convenient ways of composing hierarchical ODE models, and permit a qualitative analysis of their behaviour. We illustrate the central concepts using signal transduction as our main example. The ultimate aim is to introduce a general approach that provides the foundations for a structured formal engineering of large-scale models of biochemical networks.

  6. The Faster, Better, Cheaper Approach to Space Missions: An Engineering Management Assessment

    Science.gov (United States)

    Hamaker, Joe

    2000-01-01

    This paper describes, in viewgraph form, the faster, better, cheaper approach to space missions. The topics include: 1) What drives "Faster, Better, Cheaper"? 2) Why Space Programs are Costly; 3) Background; 4) Aerospace Project Management (Old Culture); 5) Aerospace Project Management (New Culture); 6) Scope of Analysis Limited to Engineering Management Culture; 7) Qualitative Analysis; 8) Some Basic Principles of the New Culture; 9) Cause and Effect; 10) "New Ways of Doing Business" Survey Results; 11) Quantitative Analysis; 12) Recent Space System Cost Trends; 13) Spacecraft Dry Weight Trend; 14) Complexity Factor Trends; 15) Cost Normalization; 16) Cost Normalization Algorithm; 17) Unnormalized Cost vs. Normalized Cost; and 18) Concluding Observations.

  7. Methodologic model to scheduling on service systems: a software engineering approach

    Directory of Open Access Journals (Sweden)

    Eduyn Ramiro Lopez-Santana

    2016-06-01

    Full Text Available This paper presents an approach of software engineering to a research proposal to make an Expert System to scheduling on service systems using methodologies and processes of software development. We use the adaptive software development as methodology for the software architecture based on the description as a software metaprocess that characterizes the research process. We make UML’s diagrams (Unified Modeling Language to provide a visual modeling that describes the research methodology in order to identify the actors, elements and interactions in the research process.

  8. A Problem and Project-Based Learning (PBL) Approach to Motivate Group Creativity in Engineering Education

    DEFF Research Database (Denmark)

    Zhou, Chunfang; Kolmos, Anette; Nielsen, Jens Frederik Dalsgaard

    2012-01-01

    In this paper, we explore how engineering students are motivated to develop group creativity in a Problem and Project- Based Learning (PBL) environment. Theoretically, we take a social cultural approach to group creativity and emphasize the influences of a learning environment on student motivation...... creativity. Thus, the supervisors are encouraged to be more aware of the complex relationships between student, teacher and task and the student response....... in group creativity development. Empirically, a case study was carried out on a student satellite project in the Department of Electronic System at Aalborg University in Denmark, by using qualitative methods including interviews and observation. The findings show that student motivation is stimulated...

  9. A Problem and Project-Based Learning (PBL) Approach to Motivate Group Creativity in Engineering Education

    DEFF Research Database (Denmark)

    Zhou, Chunfang; Kolmos, Anette; Nielsen, Jens Frederik Dalsgaard

    2012-01-01

    In this paper, we explore how engineering students are motivated to develop group creativity in a Problem and Project- Based Learning (PBL) environment. Theoretically, we take a social cultural approach to group creativity and emphasize the influences of a learning environment on student motivation...... in group creativity development. Empirically, a case study was carried out on a student satellite project in the Department of Electronic System at Aalborg University in Denmark, by using qualitative methods including interviews and observation. The findings show that student motivation is stimulated...

  10. Energy flows, material cycles and global development. A process engineering approach to the Earth system

    Energy Technology Data Exchange (ETDEWEB)

    Schaub, Georg [Karlsruher Institut fuer Technologie, Karlsruhe (Germany). Engler-Bunte-Institut; Turek, Thomas [TU Clausthal, Clausthal-Zellerfeld (Germany). Inst. fuer Chemische Verfahrenstechnik

    2011-07-01

    The book deals with the global flows of energy and materials, and changes caused by human activities. Based on these facts, the limitations of anthropogenic energy and material flows and the resulting consequences for the development of human societies are discussed. Different scenarios for lifestyle patterns are correlated with the world's future development of energy supply and climate. The book provides a process engineering approach to the Earth system and global development. It requires basic understanding of mathematics, physics, chemistry and biology, and provides an insight into the complex matter for readers ranging from undergraduate students to experts. (orig.)

  11. An Engineering Approach to Biomedical Sciences: Advanced Testing Methods and Pharmacokinetic Modeling

    Science.gov (United States)

    Lamberti, Gaetano; Cascone, Sara; Titomanlio, Giuseppe

    2012-01-01

    In this paper, the philosophy of a research in pharmacology field, driven by an engineering approach, was described along with some case histories and examples. The improvement in the testing methods for pharmaceutical systems (in-vitro techniques), as well as the proposal and the testing of mathematical models to describe the pharmacokinetics (in-silico techniques) are reported with the aim of pointing out methodologies and tools able to reduce the need of expensive and ethical problematic in-vivo measurements. PMID:23905061

  12. The Engineering and Science Issues Test (ESIT): a discipline-specific approach to assessing moral judgment.

    Science.gov (United States)

    Borenstein, Jason; Drake, Matthew J; Kirkman, Robert; Swann, Julie L

    2010-06-01

    To assess ethics pedagogy in science and engineering, we developed a new tool called the Engineering and Science Issues Test (ESIT). ESIT measures moral judgment in a manner similar to the Defining Issues Test, second edition, but is built around technical dilemmas in science and engineering. We used a quasi-experimental approach with pre- and post-tests, and we compared the results to those of a control group with no overt ethics instruction. Our findings are that several (but not all) stand-alone classes showed a significant improvement compared to the control group when the metric includes multiple stages of moral development. We also found that the written test had a higher response rate and sensitivity to pedagogy than the electronic version. We do not find significant differences on pre-test scores with respect to age, education level, gender or political leanings, but we do on whether subjects were native English speakers. We did not find significant differences on pre-test scores based on whether subjects had previous ethics instruction; this could suggest a lack of a long-term effect from the instruction.

  13. Model-based system engineering approach for the Euclid mission to manage scientific and technical complexity

    Science.gov (United States)

    Lorenzo Alvarez, Jose; Metselaar, Harold; Amiaux, Jerome; Saavedra Criado, Gonzalo; Gaspar Venancio, Luis M.; Salvignol, Jean-Christophe; Laureijs, René J.; Vavrek, Roland

    2016-08-01

    In the last years, the system engineering field is coming to terms with a paradigm change in the approach for complexity management. Different strategies have been proposed to cope with highly interrelated systems, system of systems and collaborative system engineering have been proposed and a significant effort is being invested into standardization and ontology definition. In particular, Model Based System Engineering (MBSE) intends to introduce methodologies for a systematic system definition, development, validation, deployment, operation and decommission, based on logical and visual relationship mapping, rather than traditional 'document based' information management. The practical implementation in real large-scale projects is not uniform across fields. In space science missions, the usage has been limited to subsystems or sample projects with modeling being performed 'a-posteriori' in many instances. The main hurdle for the introduction of MBSE practices in new projects is still the difficulty to demonstrate their added value to a project and whether their benefit is commensurate with the level of effort required to put them in place. In this paper we present the implemented Euclid system modeling activities, and an analysis of the benefits and limitations identified to support in particular requirement break-down and allocation, and verification planning at mission level.

  14. Current Advance and Future Prospects of Tissue Engineering Approach to Dentin/Pulp Regenerative Therapy.

    Science.gov (United States)

    Gong, Ting; Heng, Boon Chin; Lo, Edward Chin Man; Zhang, Chengfei

    2016-01-01

    Recent advances in biomaterial science and tissue engineering technology have greatly spurred the development of regenerative endodontics. This has led to a paradigm shift in endodontic treatment from simply filling the root canal systems with biologically inert materials to restoring the infected dental pulp with functional replacement tissues. Currently, cell transplantation has gained increasing attention as a scientifically valid method for dentin-pulp complex regeneration. This multidisciplinary approach which involves the interplay of three key elements of tissue engineering-stem cells, scaffolds, and signaling molecules-has produced an impressive number of favorable outcomes in preclinical animal studies. Nevertheless, many practical hurdles need to be overcome prior to its application in clinical settings. Apart from the potential health risks of immunological rejection and pathogenic transmission, the lack of a well-established banking system for the isolation and storage of dental-derived stem cells is the most pressing issue that awaits resolution and the properties of supportive scaffold materials vary across different studies and remain inconsistent. This review critically examines the classic triad of tissue engineering utilized in current regenerative endodontics and summarizes the possible techniques developed for dentin/pulp regeneration.

  15. Ecological Engineering Approaches to Improve Hydraulic Properties of Infiltration Basins Designed for Groundwater Recharge.

    Science.gov (United States)

    Gette-Bouvarot, Morgane; Volatier, Laurence; Lassabatere, Laurent; Lemoine, Damien; Simon, Laurent; Delolme, Cécile; Mermillod-Blondin, Florian

    2015-08-18

    Infiltration systems are increasingly used in urban areas for groundwater recharge. The reduction of sediment permeability by physical and/or biological processes is a major problem in management of infiltration systems often requiring expensive engineering operations for hydraulic performance maintenance. To reduce these costs and for the sake of sustainable development, we proposed to evaluate the ability of ecological engineering approaches to reduce the biological clogging of infiltration basins. A 36-day field-scale experiment using enclosures was performed to test the influences of abiotic (light reduction by shading) and biotic (introduction of the macrophyte Vallisneria spiralis (L.) or the gastropod Viviparus viviparus (Linnaeus, 1758)) treatments to limit benthic biofilm biomass and to maintain or even increase hydraulic performances. We coupled biological characterization of sediment (algal biomass, bacterial abundance, total organic carbon, total nitrogen, microbial enzymatic activity, photosynthetic activity, and photosystem II efficiency) with hydraulic conductivity measurements to assess the effects of treatments on sediment permeability. The grazer Viviparus viviparus significantly reduced benthic biofilm biomass and enhanced hydraulic conductivity. The other treatments did not produce significant changes in hydraulic conductivity although Vallisneria spiralis affected photosynthetic activity of biofilm. Finally, our results obtained with Viviparus viviparus are promising for the development of ecological engineering solutions to prevent biological fouling in infiltration systems.

  16. A Federated Search Approach to Facilitate Systematic Literature Review in Software Engineering

    Directory of Open Access Journals (Sweden)

    Mohammad Ghafari

    2012-04-01

    Full Text Available To impact industry, researchers developing technologies in academia need to provide tangible evidence of the advantages of using them. Nowadays, Systematic Literature Review (SLR has become a prominent methodology in evidence-based researches. Although adopting SLR in software engineering does not go far in practice, it has been resulted in valuable researches and is going to be more common. However, digital libraries and scientific databases as the best research resources do not provide enough mechanism for SLRs especially in software engineering. On the other hand, any loss of data may change the SLR results and leads to research bias. Accordingly, the search process and evidence collection in SLR is a critical point. This paper provides some tips to enhance the SLR process. The main contribution of this work ispresenting a federated search tool which provides an automatic integrated search mechanism in wellknown Software Engineering databases. Results of case study show that this approach not only reduces required time to do SLR and facilitate its search process, but also improves its reliability and results in the increasing trend to use SLRs.

  17. An Empirical Learning Approach towards the First Step Engineering Ethics through Field Works on Practical Environmental Issues

    Science.gov (United States)

    Nogami, Atsushi; Murata, Tomomi; Yashiro, Tomonari

    Engineering ethics is a complex hierarchical system consisting of an individual, professional and organizational ethics. It is, therefore, important to recognize the interrelated nature of them, and select the adequate contents according to the aim of engineering ethics at universities. This report describes an empirical learning approach, towards engineering ethics through an environmental engineering program based on field works for freshmen where numerous facts, roles and responsibilities coexist across several fields. We found that the program helps students understand the uncooked but attractive themes, thereby the hierarchical aspects of engineering ethics through role play and proposal for solutions. We also recognized that the proactive and challenging mind raised in this program would be carried on to the following engineering ethics course for sophomores.

  18. Combined analytical and numerical approaches in Dynamic Stability analyses of engineering systems

    Science.gov (United States)

    Náprstek, Jiří

    2015-03-01

    Dynamic Stability is a widely studied area that has attracted many researchers from various disciplines. Although Dynamic Stability is usually associated with mechanics, theoretical physics or other natural and technical disciplines, it is also relevant to social, economic, and philosophical areas of our lives. Therefore, it is useful to occasionally highlight the general aspects of this amazing area, to present some relevant examples and to evaluate its position among the various branches of Rational Mechanics. From this perspective, the aim of this study is to present a brief review concerning the Dynamic Stability problem, its basic definitions and principles, important phenomena, research motivations and applications in engineering. The relationships with relevant systems that are prone to stability loss (encountered in other areas such as physics, other natural sciences and engineering) are also noted. The theoretical background, which is applicable to many disciplines, is presented. In this paper, the most frequently used Dynamic Stability analysis methods are presented in relation to individual dynamic systems that are widely discussed in various engineering branches. In particular, the Lyapunov function and exponent procedures, Routh-Hurwitz, Liénard, and other theorems are outlined together with demonstrations. The possibilities for analytical and numerical procedures are mentioned together with possible feedback from experimental research and testing. The strengths and shortcomings of these approaches are evaluated together with examples of their effective complementing of each other. The systems that are widely encountered in engineering are presented in the form of mathematical models. The analyses of their Dynamic Stability and post-critical behaviour are also presented. The stability limits, bifurcation points, quasi-periodic response processes and chaotic regimes are discussed. The limit cycle existence and stability are examined together with their

  19. Vibration Monitoring of Gas Turbine Engines: Machine-Learning Approaches and Their Challenges

    Directory of Open Access Journals (Sweden)

    Ioannis Matthaiou

    2017-09-01

    Full Text Available In this study, condition monitoring strategies are examined for gas turbine engines using vibration data. The focus is on data-driven approaches, for this reason a novelty detection framework is considered for the development of reliable data-driven models that can describe the underlying relationships of the processes taking place during an engine’s operation. From a data analysis perspective, the high dimensionality of features extracted and the data complexity are two problems that need to be dealt with throughout analyses of this type. The latter refers to the fact that the healthy engine state data can be non-stationary. To address this, the implementation of the wavelet transform is examined to get a set of features from vibration signals that describe the non-stationary parts. The problem of high dimensionality of the features is addressed by “compressing” them using the kernel principal component analysis so that more meaningful, lower-dimensional features can be used to train the pattern recognition algorithms. For feature discrimination, a novelty detection scheme that is based on the one-class support vector machine (OCSVM algorithm is chosen for investigation. The main advantage, when compared to other pattern recognition algorithms, is that the learning problem is being cast as a quadratic program. The developed condition monitoring strategy can be applied for detecting excessive vibration levels that can lead to engine component failure. Here, we demonstrate its performance on vibration data from an experimental gas turbine engine operating on different conditions. Engine vibration data that are designated as belonging to the engine’s “normal” condition correspond to fuels and air-to-fuel ratio combinations, in which the engine experienced low levels of vibration. Results demonstrate that such novelty detection schemes can achieve a satisfactory validation accuracy through appropriate selection of two parameters of the

  20. Finite element methods for engineering sciences. Theoretical approach and problem solving techniques

    Energy Technology Data Exchange (ETDEWEB)

    Chaskalovic, J. [Ariel University Center of Samaria (Israel); Pierre and Marie Curie (Paris VI) Univ., 75 (France). Inst. Jean le Rond d' Alembert

    2008-07-01

    This self-tutorial offers a concise yet thorough grounding in the mathematics necessary for successfully applying FEMs to practical problems in science and engineering. The unique approach first summarizes and outlines the finite-element mathematics in general and then, in the second and major part, formulates problem examples that clearly demonstrate the techniques of functional analysis via numerous and diverse exercises. The solutions of the problems are given directly afterwards. Using this approach, the author motivates and encourages the reader to actively acquire the knowledge of finite- element methods instead of passively absorbing the material, as in most standard textbooks. The enlarged English-language edition, based on the original French, also contains a chapter on the approximation steps derived from the description of nature with differential equations and then applied to the specific model to be used. Furthermore, an introduction to tensor calculus using distribution theory offers further insight for readers with different mathematical backgrounds. (orig.)

  1. Green Materials Science and Engineering Reduces Biofouling: Approaches for Medical and Membrane-based Technologies

    Directory of Open Access Journals (Sweden)

    Kerianne M Dobosz

    2015-03-01

    Full Text Available Numerous engineered and natural environments suffer deleterious effects from biofouling and/or biofilm formation. For instance, bacterial contamination on biomedical devices pose serious health concerns. In membrane-based technologies, such as desalination and wastewater reuse, biofouling decreases membrane lifetime and increases the energy required to produce clean water. Traditionally, approaches have combatted bacteria using bactericidal agents. However, due to globalization, a decline in antibiotic discovery, and the widespread resistance of microbes to many commercial antibiotics and metallic nanoparticles, new materials and approaches to reduce biofilm formation are needed. In this mini-review, we cover the recent strategies that have been explored to combat microbial contamination without exerting evolutionary pressure on microorganisms. Renewable feedstocks, relying on structure-property relationships, bioinspired/nature-derived compounds, and green processing methods are discussed. Greener strategies that mitigate biofouling hold great potential to positively impact human health and safety.

  2. Molecular basis of glyphosate resistance-different approaches through protein engineering.

    Science.gov (United States)

    Pollegioni, Loredano; Schonbrunn, Ernst; Siehl, Daniel

    2011-08-01

    Glyphosate (N-phosphonomethyl-glycine) is the most widely used herbicide in the world: glyphosate-based formulations exhibit broad-spectrum herbicidal activity with minimal human and environmental toxicity. The extraordinary success of this simple, small molecule is mainly attributable to the high specificity of glyphosate for the plant enzyme enolpyruvyl shikimate-3-phosphate synthase in the shikimate pathway, leading to the biosynthesis of aromatic amino acids. Starting in 1996, transgenic glyphosate-resistant plants were introduced, thus allowing application of the herbicide to the crop (post-emergence) to remove emerged weeds without crop damage. This review focuses on mechanisms of resistance to glyphosate as obtained through natural diversity, the gene-shuffling approach to molecular evolution, and a rational, structure-based approach to protein engineering. In addition, we offer a rationale for the means by which the modifications made have had their intended effect.

  3. Green materials science and engineering reduces biofouling: approaches for medical and membrane-based technologies.

    Science.gov (United States)

    Dobosz, Kerianne M; Kolewe, Kristopher W; Schiffman, Jessica D

    2015-01-01

    Numerous engineered and natural environments suffer deleterious effects from biofouling and/or biofilm formation. For instance, bacterial contamination on biomedical devices pose serious health concerns. In membrane-based technologies, such as desalination and wastewater reuse, biofouling decreases membrane lifetime, and increases the energy required to produce clean water. Traditionally, approaches have combatted bacteria using bactericidal agents. However, due to globalization, a decline in antibiotic discovery, and the widespread resistance of microbes to many commercial antibiotics and metallic nanoparticles, new materials, and approaches to reduce biofilm formation are needed. In this mini-review, we cover the recent strategies that have been explored to combat microbial contamination without exerting evolutionary pressure on microorganisms. Renewable feedstocks, relying on structure-property relationships, bioinspired/nature-derived compounds, and green processing methods are discussed. Greener strategies that mitigate biofouling hold great potential to positively impact human health and safety.

  4. Using a holistic approach to assess the impact of engineered nanomaterials inducing toxicity in aquatic systems.

    Science.gov (United States)

    He, Xiaojia; Aker, Winfred G; Leszczynski, Jerzy; Hwang, Huey-Min

    2014-03-01

    In this report, we critically reviewed selected intrinsic physicochemical properties of engineered nanomaterials (ENMs) and their role in the interaction of the ENMs with the immediate surroundings in representative aquatic environments. The behavior of ENMs with respect to dynamic microenvironments at the nano-bio-eco interface level, and the resulting impact on their toxicity, fate, and exposure potential are elaborated. Based on this literature review, we conclude that a holistic approach is urgently needed to fulfill our knowledge gap regarding the safety of discharged ENMs. This comparative approach affords the capability to recognize and understand the potential hazards of ENMs and their toxicity mechanisms, and ultimately to establish a quantitative and reliable system to predict such outcomes.

  5. A Model-Free Diagnosis Approach for Intake Leakage Detection and Characterization in Diesel Engines

    Directory of Open Access Journals (Sweden)

    Ghaleb Hoblos

    2015-07-01

    Full Text Available Feature selection is an essential step for data classification used in fault detection and diagnosis processes. In this work, a new approach is proposed, which combines a feature selection algorithm and a neural network tool for leak detection and characterization tasks in diesel engine air paths. The Chi square classifier is used as the feature selection algorithm and the neural network based on Levenberg-Marquardt is used in system behavior modeling. The obtained neural network is used for leak detection and characterization. The model is learned and validated using data generated by xMOD. This tool is used again for testing. The effectiveness of the proposed approach is illustrated in simulation when the system operates on a low speed/load and the considered leak affecting the air path is very small.

  6. Green materials science and engineering reduces biofouling: approaches for medical and membrane-based technologies

    Science.gov (United States)

    Dobosz, Kerianne M.; Kolewe, Kristopher W.; Schiffman, Jessica D.

    2015-01-01

    Numerous engineered and natural environments suffer deleterious effects from biofouling and/or biofilm formation. For instance, bacterial contamination on biomedical devices pose serious health concerns. In membrane-based technologies, such as desalination and wastewater reuse, biofouling decreases membrane lifetime, and increases the energy required to produce clean water. Traditionally, approaches have combatted bacteria using bactericidal agents. However, due to globalization, a decline in antibiotic discovery, and the widespread resistance of microbes to many commercial antibiotics and metallic nanoparticles, new materials, and approaches to reduce biofilm formation are needed. In this mini-review, we cover the recent strategies that have been explored to combat microbial contamination without exerting evolutionary pressure on microorganisms. Renewable feedstocks, relying on structure-property relationships, bioinspired/nature-derived compounds, and green processing methods are discussed. Greener strategies that mitigate biofouling hold great potential to positively impact human health and safety. PMID:25852659

  7. Tissue Engineering Approaches in the Design of Healthy and Pathological In Vitro Tissue Models

    Science.gov (United States)

    Caddeo, Silvia; Boffito, Monica; Sartori, Susanna

    2017-01-01

    In the tissue engineering (TE) paradigm, engineering and life sciences tools are combined to develop bioartificial substitutes for organs and tissues, which can in turn be applied in regenerative medicine, pharmaceutical, diagnostic, and basic research to elucidate fundamental aspects of cell functions in vivo or to identify mechanisms involved in aging processes and disease onset and progression. The complex three-dimensional (3D) microenvironment in which cells are organized in vivo allows the interaction between different cell types and between cells and the extracellular matrix, the composition of which varies as a function of the tissue, the degree of maturation, and health conditions. In this context, 3D in vitro models can more realistically reproduce a tissue or organ than two-dimensional (2D) models. Moreover, they can overcome the limitations of animal models and reduce the need for in vivo tests, according to the “3Rs” guiding principles for a more ethical research. The design of 3D engineered tissue models is currently in its development stage, showing high potential in overcoming the limitations of already available models. However, many issues are still opened, concerning the identification of the optimal scaffold-forming materials, cell source and biofabrication technology, and the best cell culture conditions (biochemical and physical cues) to finely replicate the native tissue and the surrounding environment. In the near future, 3D tissue-engineered models are expected to become useful tools in the preliminary testing and screening of drugs and therapies and in the investigation of the molecular mechanisms underpinning disease onset and progression. In this review, the application of TE principles to the design of in vitro 3D models will be surveyed, with a focus on the strengths and weaknesses of this emerging approach. In addition, a brief overview on the development of in vitro models of healthy and pathological bone, heart, pancreas, and

  8. Tissue Engineering Approaches in the Design of Healthy and Pathological In Vitro Tissue Models

    Directory of Open Access Journals (Sweden)

    Silvia Caddeo

    2017-07-01

    Full Text Available In the tissue engineering (TE paradigm, engineering and life sciences tools are combined to develop bioartificial substitutes for organs and tissues, which can in turn be applied in regenerative medicine, pharmaceutical, diagnostic, and basic research to elucidate fundamental aspects of cell functions in vivo or to identify mechanisms involved in aging processes and disease onset and progression. The complex three-dimensional (3D microenvironment in which cells are organized in vivo allows the interaction between different cell types and between cells and the extracellular matrix, the composition of which varies as a function of the tissue, the degree of maturation, and health conditions. In this context, 3D in vitro models can more realistically reproduce a tissue or organ than two-dimensional (2D models. Moreover, they can overcome the limitations of animal models and reduce the need for in vivo tests, according to the “3Rs” guiding principles for a more ethical research. The design of 3D engineered tissue models is currently in its development stage, showing high potential in overcoming the limitations of already available models. However, many issues are still opened, concerning the identification of the optimal scaffold-forming materials, cell source and biofabrication technology, and the best cell culture conditions (biochemical and physical cues to finely replicate the native tissue and the surrounding environment. In the near future, 3D tissue-engineered models are expected to become useful tools in the preliminary testing and screening of drugs and therapies and in the investigation of the molecular mechanisms underpinning disease onset and progression. In this review, the application of TE principles to the design of in vitro 3D models will be surveyed, with a focus on the strengths and weaknesses of this emerging approach. In addition, a brief overview on the development of in vitro models of healthy and pathological bone, heart

  9. A system-of-systems approach as a broad and integrated paradigm for sustainable engineered nanomaterials.

    Science.gov (United States)

    Tolaymat, Thabet; El Badawy, Amro; Sequeira, Reynold; Genaidy, Ash

    2015-04-01

    There is an urgent need for a trans-disciplinary approach for the collective evaluation of engineered nanomaterial (ENM) benefits and risks. Currently, research studies are mostly focused on examining effects at individual endpoints with emphasis on ENM risk effects. Less research work is pursuing the integration needed to advance the science of sustainable ENMs. Therefore, the primary objective of this article is to discuss the system-of-systems (SoS) approach as a broad and integrated paradigm to examine ENM benefits and risks to society, environment, and economy (SEE) within a sustainability context. The aims are focused on: (a) current approaches in the scientific literature and the need for a broad and integrated approach, (b) documentation of ENM SoS in terms of architecture and governing rules and practices within sustainability context, and (c) implementation plan for the road ahead. In essence, the SoS architecture is a communication vehicle offering the opportunity to track benefits and risks in an integrated fashion so as to understand the implications and make decisions about advancing the science of sustainable ENMs. In support of the SoS architecture, we propose using an analytic-based decision support system consisting of a knowledge base and analytic engine along the benefit and risk informatics routes in the SEE system to build sound decisions on what constitutes sustainable and unsustainable ENMs in spite of the existing uncertainties and knowledge gaps. The work presented herein is neither a systematic review nor a critical appraisal of the scientific literature. Rather, it is a position paper that largely expresses the views of the authors based on their expert opinion drawn from industrial and academic experience.

  10. App Factory: A Flexible Approach to Rehabilitation Engineering in an Era of Rapid Technology Advancement.

    Science.gov (United States)

    Jones, Michael; Mueller, James; Morris, John

    2016-08-15

    This article describes a flexible and effective approach to research and development in an era of rapid technological advancement. The approach relies on secondary dispersal of grant funds to commercial developers through a competitive selection process. This "App Factory" model balances the practical reliance on multi-year funding needed to sustain a rehabilitation engineering research center (RERC), with the need for agility and adaptability of development efforts undertaken in a rapidly-changing technology environment. This approach also allows us to take advantage of technical expertise needed to accomplish a particular development task, and provides incentives to deliver successful products in a cost-effective manner. In this article, we describe the App Factory structure, process and results achieved to date; and we discuss the lessons learned and the potential relevance of this approach for other grant-funded research and development efforts. Data presented on the direct costs and number of downloads of the 16 app development projects funded in the App Factory's first 3 years show that it can be an effective means for supporting focused, short-term assistive technology development projects.

  11. A Science, Engineering and Technology (SET) Approach Improves Science Process Skills in 4-H Animal Science Participants

    Science.gov (United States)

    Clarke, Katie C.

    2010-01-01

    A new Science, Engineering and Technology (SET) approach was designed for youth who participated in the Minnesota State Fair Livestock interview process. The project and evaluation were designed to determine if the new SET approach increased content knowledge and science process skills in participants. Results revealed that youth participants not…

  12. A Science, Engineering and Technology (SET) Approach Improves Science Process Skills in 4-H Animal Science Participants

    Science.gov (United States)

    Clarke, Katie C.

    2010-01-01

    A new Science, Engineering and Technology (SET) approach was designed for youth who participated in the Minnesota State Fair Livestock interview process. The project and evaluation were designed to determine if the new SET approach increased content knowledge and science process skills in participants. Results revealed that youth participants not…

  13. Development of a Study Module on and Pedagogical Approaches to Industrial Environmental Engineering and Sustainability in Mozambique

    Science.gov (United States)

    Husgafvel, Roope; Martikka, Mikko; Egas, Andrade; Ribiero, Natasha; Dahl, Olli

    2017-01-01

    Addressing the sustainability challenges in the forest sector in Mozambique requires capacity building for higher education and training of new skilled expert and future decision-makers. Our approach was to develop a study module on and pedagogical approaches to industrial environmental engineering and sustainability. The idea was to develop a…

  14. Tissue engineering approaches for studying the effect of biochemical and physiological stimuli on cell behavior

    Science.gov (United States)

    Jimenez Vergara, Andrea Carolina

    Tissue engineering (TE) approaches have emerged as an alternative to traditional tissue and organ replacements. The aim of this work was to contribute to the understanding of the effects of cell-material and endothelial cell (EC) paracrine signaling on cell responses using poly(ethylene glycol) diacrylate (PEGDA) hydrogels as a material platform. Three TE applications were explored. First, the effect of glycosaminoglycan (GAG) identity was evaluated for vocal fold restoration. Second, the influence of GAG identity was explored and a novel approach for stable endothelialization was developed for vascular graft applications. Finally, EC paracrine signaling in the presence of cyclic stretch, and hydrophobicity and inorganic content were studied for osteogenic applications. In terms of vocal fold restoration, it was found that vocal fold fibroblast (VFF) phenotype and extracellular matrix (ECM) production were impacted by GAG identity. VFF phenotype was preserved in long-term cultured hydrogels containing high molecular weight hyaluronan (HAHMW). Furthermore, collagen I deposition, fibronectin production and smooth muscle α-actin (SM-α-actin) expression in PEG-HA, PEG-chondroitin sulfate C and PEG-heparan sulfate (HS) gels suggest that CSC and HS may be undesirable for vocal fold implants. Regarding vascular graft applications, the impact of GAG identity on smooth muscle cell (SMC) foam cell formation was explored. Results support the increasing body of literature that suggests a critical role for dermatan sulfate (DS)-bearing proteoglycans in early atherosclerosis. In addition, an approach for fabricating bi-layered tissue engineering vascular grafts (TEVGs) with stable endothelialization was validated using PEGDA as an intercellular “cementing” agent between adjacent endothelial cells (ECs). Finally, mesenchymal stem cell (MSC) differentiation toward osteogenic like cells was evaluated. ECM and cell phenotypic data showed that elevated scaffold inorganic

  15. Linking biogeomorphic feedbacks from ecosystem engineer to landscape scale: a panarchy approach

    Science.gov (United States)

    Eichel, Jana

    2017-04-01

    Scale is a fundamental concept in both ecology and geomorphology. Therefore, scale-based approaches are a valuable tool to bridge the disciplines and improve the understanding of feedbacks between geomorphic processes, landforms, material and organisms and ecological processes in biogeomorphology. Yet, linkages between biogeomorphic feedbacks on different scales, e.g. between ecosystem engineering and landscape scale patterns and dynamics, are not well understood. A panarchy approach sensu Holling et al. (2002) can help to close this research gap and explain how structure and function are created in biogeomorphic ecosystems. Based on results from previous biogeomorphic research in Turtmann glacier foreland (Switzerland; Eichel, 2017; Eichel et al. 2013, 2016), a panarchy concept is presented for lateral moraine slope biogeomorphic ecosystems. It depicts biogeomorphic feedbacks on different spatiotemporal scales as a set of nested adaptive cycles and links them by 'remember' and 'revolt' connections. On a small scale (cm2 - m2; seconds to years), the life cycle of the ecosystem engineer Dryas octopetala L. is considered as an adaptive cycle. Biogeomorphic succession within patches created by geomorphic processes represents an intermediate scale adaptive cycle (m2 - ha, years to decades), while geomorphic and ecologic pattern development at a landscape scale (ha - km2, decades to centuries) can be illustrated by an adaptive cycle of ‚biogeomorphic patch dynamics' (Eichel, 2017). In the panarchy, revolt connections link the smaller scale adaptive cycles to larger scale cycles: on lateral moraine slopes, the development of ecosystem engineer biomass and cover controls the engineering threshold of the biogeomorphic feedback window (Eichel et al., 2016) and therefore the onset of the biogeomorphic phase during biogeomorphic succession. In this phase, engineer patches and biogeomorphic structures can be created in the patch mosaic of the landscape. Remember connections

  16. Enzymatic Menthol Production: One-Pot Approach Using Engineered Escherichia coli.

    Science.gov (United States)

    Toogood, Helen S; Ní Cheallaigh, Aisling; Tait, Shirley; Mansell, David J; Jervis, Adrian; Lygidakis, Antonios; Humphreys, Luke; Takano, Eriko; Gardiner, John M; Scrutton, Nigel S

    2015-10-16

    Menthol isomers are high-value monoterpenoid commodity chemicals, produced naturally by mint plants, Mentha spp. Alternative clean biosynthetic routes to these compounds are commercially attractive. Optimization strategies for biocatalytic terpenoid production are mainly focused on metabolic engineering of the biosynthesis pathway within an expression host. We circumvent this bottleneck by combining pathway assembly techniques with classical biocatalysis methods to engineer and optimize cell-free one-pot biotransformation systems and apply this strategy to the mint biosynthesis pathway. Our approach allows optimization of each pathway enzyme and avoidance of monoterpenoid toxicity issues to the host cell. We have developed a one-pot (bio)synthesis of (1R,2S,5R)-(-)-menthol and (1S,2S,5R)-(+)-neomenthol from pulegone, using recombinant Escherichia coli extracts containing the biosynthetic genes for an "ene"-reductase (NtDBR from Nicotiana tabacum) and two menthone dehydrogenases (MMR and MNMR from Mentha piperita). Our modular engineering strategy allowed each step to be optimized to improve the final production level. Moderate to highly pure menthol (79.1%) and neomenthol (89.9%) were obtained when E. coli strains coexpressed NtDBR with only MMR or MNMR, respectively. This one-pot biocatalytic method allows easier optimization of each enzymatic step and easier modular combination of reactions to ultimately generate libraries of pure compounds for use in high-throughput screening. It will be, therefore, a valuable addition to the arsenal of biocatalysis strategies, especially when applied for (semi)-toxic chemical compounds.

  17. Gene editing and genetic engineering approaches for advanced probiotics: A Review.

    Science.gov (United States)

    Yadav, Ruby; Kumar, Vishal; Baweja, Mehak; Shukla, Pratyoosh

    2017-01-10

    The applications of probiotics are significant and thus resulted in need of genome analysis of probiotic strains. Various omics methods and systems biology approaches enables us to understand and optimize the metabolic processes. These techniques have increased the researcher's attention towards gut microbiome and provided a new source for the revelation of uncharacterized biosynthetic pathways which enables novel metabolic engineering approaches. In recent years, the broad and quantitative analysis of modified strains relies on systems biology tools such as in silico design which are commonly used methods for improving strain performance. The genetic manipulation of probiotic microorganisms is crucial for defining their role in intestinal microbiota and exploring their beneficial properties. This review describes an overview of gene editing and system biology approaches, highlighting the advent of omics methods which allows the study of new routes for studying probiotic bacteria. We have also summarized gene editing tools like TALEN, ZFNs and CRISPR-Cas that edits or cleave the specific target DNA. Furthermore, in this review an overview of proposed design of advanced customized probiotic is also hypothesized to improvise the probiotics.

  18. Pharmaceutical proteins in plants. A strategic genetic engineering approach for the production of tuberculosis antigens.

    Science.gov (United States)

    Frutos, Roger; Denise, Hubert; Vivares, Christian; Neuhaus, Jean-Marc; Vitale, Sandro; Pedrazzini, Emmanuela; Ma, Julian; Dix, Phil; Gray, John; Pezzotti, Mario; Conrad, Udo; Robinson, David

    2008-12-01

    Tuberculosis (TB) is a re-emerging disease that is considered a major human health priority as well as an important disease of livestock. TB is also a zoonosis, and Mycobacterium tuberculosis and M. bovis, the human and bovine causative agents, respectively, are very closely related. Protection against TB is essentially achieved through vaccination with the Bacille Calmetle-Guerin (BCG) strain of M. bovis. Protection is, however, incomplete, and novel improved vaccines are currently under investigation. Production of protective antigens in transgenic plants, or "pharming," is a promising emerging approach, and a zoonosis-like TB is a good model for investigating the potential of this approach. Pharma-Planta, a European Commission-funded project and consortium, was set up to address this topic, within which a component is aimed at assessing the production efficacy and stability of the TB antigens in different compartments of the plant cell. This article is meant to introduce this promising approach for veterinary medicine by describing the ongoing project and its specific genetic engineering strategy.

  19. A biomedical engineering approach to mitigate the errors of prostate biopsy.

    Science.gov (United States)

    Ahmed, Hashim Uddin; Emberton, Mark; Kepner, Gordon; Kepner, Jeremy

    2012-02-07

    The current protocol for detecting and ruling out prostate cancer involves serum PSA testing followed by sampling of the prostate using a transrectal ultrasonography (TRUS)-guided biopsy. Many specialists have discussed how PSA screening has contributed to underdetection of clinically significant prostate cancer, overdiagnosis of clinically insignificant disease and poor risk stratification; however, little consideration has been given to the role of TRUS-guided biopsy in these errors. The performance of TRUS-guided biopsy is constrained by the biomechanical attributes of the sampling strategy, resulting in suboptimal detection efficiency of each core. By using a biomedical engineering approach, a uniform grid sampling strategy could be used to improve the detection efficiency of prostate biopsy. Moreover, the calibration of the sampling can be adjusted by altering the distance between needle deployments. Our model shows that for any given number of needle trajectories, a uniform grid approach will be superior to a divergent, nonuniform strategy for the detection of clinically important disease. This is an important message that should result in a move away from divergent sampling to a uniform grid approach for prostate biopsy.

  20. Inquiry guided learning in a chemical engineering core curriculum: General instructional approach and specific application to the fluid mechanics case

    OpenAIRE

    Atilhan, Mert; Eljack, Fadwa; Alfadala, Hassan; Froyd, Jeffrey E.; El-Halwagi, Mahmoud; Mahalec, Vladimir

    2014-01-01

    This paper presents results from a preliminary study of the effectiveness of using inquiry-guided learning instructional strategies both in chemical engineering classrooms and laboratories. For readers unfamiliar with the instructional strategy, the paper describes the general approach and then reports on results of its application for the fluid mechanics course taken by undergraduate students in the Chemical Engineering Department at Qatar University. Inquiry-guided activities were developed...

  1. A New Approach for NOx Soft Sensors for the Aftertreatment of Diesel Engines

    Science.gov (United States)

    Ishizuka, S.; Kajiwara, I.; Sato, J.; Hanamura, Y.

    2016-09-01

    To maintain the NOX concentration at an appropriate level, traditionally an air-path control that regulates the intake and exhaust system of diesel engines aims to control the mass air flow and the manifold absolute pressure, which influence the production of NOX. To improve the control accuracy, a more recent approach takes the NOX concentration directly as a controlled output variable, but the sensors monitoring the NOX concentration are slow to respond. Consequently, a direct sensor is inappropriate as a feedback controller. Instead a mechanism called a soft sensor, which computes the NOX concentration from state quantities of diesel engines, is used. Because the prediction accuracy from the sensor model greatly affects the control performance, it is important to improve the model accuracy. However, deviations in the steady state indicate an insufficient model accuracy. This study proposes a method to construct an adaptive NOX soft sensor that corrects the parameters of the sensor model sequentially using the simultaneous perturbation stochastic approximation while comparing the values computed by the software to actual measurements as well as examines the effectiveness of the proposed method experimentally.

  2. The living shunt: a tissue engineering approach in the treatment of hydrocephalus.

    Science.gov (United States)

    Lee, I W; Vacanti, J P; Taylor, G A; Madsen, J R

    2000-01-01

    Tissue engineering is the use of cultured cells seeded into biodegradable polymers to create custom designed, living implantable devices. As a first approach to the use of this technique in the treatment of hydrocephalus, we have prepared chondrocyte-seeded polyglycolic acid (PGA) tubes coated with polylactic glycolic acid (PGLA), implanted initially with thin silastic stents removed four weeks after shunt insertion. The use of bovine xenograft cells in athymic (nude) rats resulted in more efficient seeding with chondrocytes, stiffer tube walls, and better patency. When implanted in 6-week-old rats made hydrocephalic by cisternal injection of kaolin at 4 weeks of age, six of eight 'living shunts' remained patent to radio-opaque contrast injection at two weeks after stent removal. At four weeks after stent removal, all four of the shunts had occluded at the ventricular end, three of the four apparently due to growth of the animal. We conclude that polymer type, cell type, and cell density will require considerable optimization, but a working tissue engineered shunt is feasible and may one day address some problems of interactions of living tissue and inert polymer.

  3. Current Advance and Future Prospects of Tissue Engineering Approach to Dentin/Pulp Regenerative Therapy

    Directory of Open Access Journals (Sweden)

    Ting Gong

    2016-01-01

    Full Text Available Recent advances in biomaterial science and tissue engineering technology have greatly spurred the development of regenerative endodontics. This has led to a paradigm shift in endodontic treatment from simply filling the root canal systems with biologically inert materials to restoring the infected dental pulp with functional replacement tissues. Currently, cell transplantation has gained increasing attention as a scientifically valid method for dentin-pulp complex regeneration. This multidisciplinary approach which involves the interplay of three key elements of tissue engineering—stem cells, scaffolds, and signaling molecules—has produced an impressive number of favorable outcomes in preclinical animal studies. Nevertheless, many practical hurdles need to be overcome prior to its application in clinical settings. Apart from the potential health risks of immunological rejection and pathogenic transmission, the lack of a well-established banking system for the isolation and storage of dental-derived stem cells is the most pressing issue that awaits resolution and the properties of supportive scaffold materials vary across different studies and remain inconsistent. This review critically examines the classic triad of tissue engineering utilized in current regenerative endodontics and summarizes the possible techniques developed for dentin/pulp regeneration.

  4. Current Advance and Future Prospects of Tissue Engineering Approach to Dentin/Pulp Regenerative Therapy

    Science.gov (United States)

    Gong, Ting; Heng, Boon Chin; Lo, Edward Chin Man; Zhang, Chengfei

    2016-01-01

    Recent advances in biomaterial science and tissue engineering technology have greatly spurred the development of regenerative endodontics. This has led to a paradigm shift in endodontic treatment from simply filling the root canal systems with biologically inert materials to restoring the infected dental pulp with functional replacement tissues. Currently, cell transplantation has gained increasing attention as a scientifically valid method for dentin-pulp complex regeneration. This multidisciplinary approach which involves the interplay of three key elements of tissue engineering—stem cells, scaffolds, and signaling molecules—has produced an impressive number of favorable outcomes in preclinical animal studies. Nevertheless, many practical hurdles need to be overcome prior to its application in clinical settings. Apart from the potential health risks of immunological rejection and pathogenic transmission, the lack of a well-established banking system for the isolation and storage of dental-derived stem cells is the most pressing issue that awaits resolution and the properties of supportive scaffold materials vary across different studies and remain inconsistent. This review critically examines the classic triad of tissue engineering utilized in current regenerative endodontics and summarizes the possible techniques developed for dentin/pulp regeneration. PMID:27069484

  5. A MultiAir®/MultiFuel Approach to Enhancing Engine System Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Reese, Ronald [Chrysler Group LLC., Auburn Hills, MI (United States)

    2015-05-20

    FCA US LLC (formally known as Chrysler Group LLC, and hereinafter “Chrysler”) was awarded an American Recovery and Reinvestment Act (ARRA) funded project by the Department of Energy (DOE) titled “A MultiAir®/MultiFuel Approach to Enhancing Engine System Efficiency” (hereinafter “project”). This award was issued after Chrysler submitted a proposal for Funding Opportunity Announcement DE-FOA- 0000079, “Systems Level Technology Development, Integration, and Demonstration for Efficient Class 8 Trucks (SuperTruck) and Advanced Technology Powertrains for Light-Duty Vehicles (ATP-LD).” Chrysler started work on this project on June 01, 2010 and completed testing activities on August 30, 2014. Overall objectives of this project were; Demonstrate a 25% improvement in combined Federal Test Procedure (FTP) City and Highway fuel economy over a 2009 Chrysler minivan; Accelerate the development of highly efficient engine and powertrain systems for light-duty vehicles, while meeting future emissions standards; and Create and retain jobs in accordance with the American Recovery and Reinvestment Act of 2009

  6. Ontological Engineering Approach towards Trust Oriented Security Framework for Adhoc Networks

    Directory of Open Access Journals (Sweden)

    Amandeep Verma

    2012-06-01

    Full Text Available Conventionally, user authentication and access control mechanisms would be almost enough, to handle security for stand-alone computers and small networks. Ad hoc networks are illustrated by multi-hop wireless connectivity and recurrently changing network topology which have made them infrastructure less. Adding trust to the existing security infrastructures would improvise the security of these environments. Describing trust relations and their sub-components using ontologies, creates a methodology and mechanism in order to efficiently design and engineer trust networks. This is going tobe used as a service for providing trust for ad hoc network at any level i.e. routing, authentication or access control. A trust oriented security framework for adhoc network using ontological engineering approach is proposed by modeling ad hoc network, the OLSR (Optimized Link State Routing protocol and trust model as OWL (Ontology Web language ontologies, which are integrated using Jena. In this model, a trustor can calculate its trust about trustee and use the calculated trust values to make decisions depending on the context of the application or interaction about granting or rejecting it. A number ofexperiments with a possible implementation of suggested framework are performed to make out the characteristics of the trust model and its effect on the ad hoc network operations.

  7. An Approach to Integrating Health Disparities within Undergraduate Biomedical Engineering Education.

    Science.gov (United States)

    Vazquez, Maribel; Marte, Otto; Barba, Joseph; Hubbard, Karen

    2017-08-28

    Health disparities are preventable differences in the incidence, prevalence and burden of disease among communities targeted by gender, geographic location, ethnicity and/or socio-economic status. While biomedical research has identified partial origin(s) of divergent burden and impact of disease, the innovation needed to eradicate health disparities in the United States requires unique engagement from biomedical engineers. Increasing awareness of the prevalence and consequences of health disparities is particularly attractive to today's undergraduates, who have undauntedly challenged paradigms believed to foster inequality. Here, the Department of Biomedical Engineering at The City College of New York (CCNY) has leveraged its historical mission of access-and-excellence to integrate the study of health disparities into undergraduate BME curricula. This article describes our novel approach in a multiyear study that: (i) Integrated health disparities modules at all levels of the required undergraduate BME curriculum; (ii) Developed opportunities to include impacts of health disparities into undergraduate BME research projects and mentored High School summer STEM training; and (iii) Established health disparities-based challenges as BME capstone design and/or independent entrepreneurship projects. Results illustrate the rising awareness of health disparities among the youngest BMEs-to-be, as well as abundant undergraduate desire to integrate health disparities within BME education and training.

  8. A Multicellular Approach Forms a Significant Amount of Tissue-Engineered Small Intestine in the Mouse

    Science.gov (United States)

    Sala, Frédéric G.; Matthews, Jamil A.; Speer, Allison L.; Torashima, Yasuhiro; Barthel, Erik R.

    2011-01-01

    Tissue-engineered small intestine (TESI) has successfully been used to rescue Lewis rats after massive small bowel resection. In this study, we transitioned the technique to a mouse model, allowing investigation of the processes involved during TESI formation through the transgenic tools available in this species. This is a necessary step toward applying the technique to human therapy. Multicellular organoid units were derived from small intestines of transgenic mice and transplanted within the abdomen on biodegradable polymers. Immunofluorescence staining was used to characterize the cellular processes during TESI formation. We demonstrate the preservation of Lgr5- and DcamKl1-positive cells, two putative intestinal stem cell populations, in proximity to their niche mesenchymal cells, the intestinal subepithelial myofibroblasts (ISEMFs), at the time of implantation. Maintenance of the relationship between ISEMF and crypt epithelium is observed during the growth of TESI. The engineered small intestine has an epithelium containing a differentiated epithelium next to an innervated muscularis. Lineage tracing demonstrates that all the essential components, including epithelium, muscularis, nerves, and some of the blood vessels, are of donor origin. This multicellular approach provides the necessary cell population to regenerate large amounts of intestinal tissue that could be used to treat short bowel syndrome. PMID:21395443

  9. NDE using sensor based approach to propulsion health monitoring of a turbine engine disk

    Science.gov (United States)

    Abdul-Aziz, Ali; Woike, Mark R.; Abumeri, G.; Lekki, John D.; Baaklini, George Y.

    2009-03-01

    Rotor health monitoring and on-line damage detection have been increasingly gaining interest to manufacturers of aircraft engines, primarily to increase safety of operation and lower the high maintenance costs. But health monitoring in the presence of scatter in the loading conditions, crack size, disk geometry, and material property is rather challenging. However, detection factors that cause fractures and hidden internal cracks can be implemented via noninvasive types of health monitoring and or nondestructive evaluation techniques. These evaluations go further to inspect materials discontinuities and other anomalies that have grown to become critical defects that can lead to failure. To address the bulk of these concerning issues and understand the technical aspects leading to these outcomes, a combined analytical and experimental study is being thought. Results produced from the experiments such as blade tip displacement and other data collected from tests conducted at the NASA Glenn Research Center's Rotordynamics Laboratory, a high precision spin rig, are evaluated, discussed and compared with data predicted from finite element analysis simulating the engine rotor disk spinning at various rotational speeds. Further computations using the progressive failure analysis (PFA) approach with GENOA code [6] to additionally assess the structural response, damage initiation, propagation, and failure criterion are also performed. This study presents an inclusive evaluation of an on-line health monitoring of a rotating disk and an examination for the capability of the in-house spin system in support of ongoing research under the NASA Integrated Vehicle Health Management (IVHM) program.

  10. Aircraft Engine Noise Scattering by Fuselage and Wings: A Computational Approach

    Science.gov (United States)

    Stanescu, D.; Hussaini, M. Y.; Farassat, F.

    2003-01-01

    The paper presents a time-domain method for computation of sound radiation from aircraft engine sources to the far-field. The effects of nonuniform flow around the aircraft and scattering of sound by fuselage and wings are accounted for in the formulation. The approach is based on the discretization of the inviscid flow equations through a collocation form of the Discontinuous Galerkin spectral element method. An isoparametric representation of the underlying geometry is used in order to take full advantage of the spectral accuracy of the method. Large-scale computations are made possible by a parallel implementation based on message passing. Results obtained for radiation from an axisymmetric nacelle alone are compared with those obtained when the same nacelle is installed in a generic configuration, with and without a wing.

  11. Use of Time- and Frequency-Domain Approaches for Damage Detection in Civil Engineering Structures

    Directory of Open Access Journals (Sweden)

    V. H. Nguyen

    2014-01-01

    Full Text Available The aim of this paper is to apply both time- and frequency-domain-based approaches on real-life civil engineering structures and to assess their capability for damage detection. The methodology is based on Principal Component Analysis of the Hankel matrix built from output-only measurements and of Frequency Response Functions. Damage detection is performed using the concept of subspace angles between a current (possibly damaged state and a reference (undamaged state. The first structure is the Champangshiehl Bridge located in Luxembourg. Several damage levels were intentionally created by cutting a growing number of prestressed tendons and vibration data were acquired by the University of Luxembourg for each damaged state. The second example consists in reinforced and prestressed concrete panels. Successive damages were introduced in the panels by loading heavy weights and by cutting steel wires. The illustrations show different consequences in damage identification by the considered techniques.

  12. An integrated approach to develop professional and technical skills for informatics engineering students

    Science.gov (United States)

    Fernandes, João M.; van Hattum-Janssen, Natascha; Nestor Ribeiro, António; Fonte, Victor; Santos, Luís Paulo; Sousa, Pedro

    2012-05-01

    Many of the current approaches used in teaching and learning in engineering education are not the most appropriate to prepare students for the challenges they will face in their professional careers. The active involvement of students in their learning process facilitates the development of the technical and professional competencies they need as professionals. This article describes the organisation and impact of a mini-conference and project work - the creation of a software product and its introduction in the market - aimed at the development of professional competencies in general and writing skills in particular. The course was evaluated by assessing the students' perception of the development of a number of professional competencies through a questionnaire completed by 125 students from two consecutive year groups. The results indicate that the project work and the mini-conference had a positive impact on students' perceptions of the development of professional competencies.

  13. Marine algae sulfated polysaccharides for tissue engineering and drug delivery approaches.

    Science.gov (United States)

    Silva, Tiago H; Alves, Anabela; Popa, Elena G; Reys, Lara L; Gomes, Manuela E; Sousa, Rui A; Silva, Simone S; Mano, João F; Reis, Rui L

    2012-01-01

    Biomedical field is constantly requesting for new biomaterials, with innovative properties. Natural polymers appear as materials of election for this goal due to their biocompatibility and biodegradability. In particular, materials found in marine environment are of great interest since the chemical and biological diversity found in this environment is almost uncountable and continuously growing with the research in deeper waters. Moreover, there is also a slower risk of these materials to pose illnesses to humans.   In particular, sulfated polysaccharides can be found in marine environment, in different algae species. These polysaccharides don't have equivalent in the terrestrial plants and resembles the chemical and biological properties of mammalian glycosaminoglycans. In this perspective, are receiving growing interest for application on health-related fields. On this review, we will focus on the biomedical applications of marine algae sulfated polymers, in particular on the development of innovative systems for tissue engineering and drug delivery approaches.

  14. Vapour and acid components separation from gases by membranes principles and engineering approach to membranes development

    Science.gov (United States)

    Kagramanov, G. G.; Storojuk, I. P.; Farnosova, E. N.

    2016-09-01

    The modern commercially available polymer membranes and membrane modules for purification of gases, containing acid components, simultaneously with dehumidification of treated gas streams, were developed and commercialized in the very end of XXth century. The membranes basic properties - selectivity (separation factor) and permeation flow rates - are relatively far from satisfying the growing and modern-scale industrial need in purification technologies and corresponding equipments. The attempt to formulate the basic principles, scientific and engineering approaches to the development of prospective membranes for the purification of gases, especially such as natural and oil gases, from acid components, simultaneously with drying them, was being made. For this purpose the influence of various factors - polymer nature, membrane type, structure, geometrical and mass-transfer characteristics, etc. - were studied and analyzed in order to formulate the basic principles and demands for development of membranes, capable to withstand successfully the sever conditions of exploitation.

  15. Development of an automated guided vehicle controller using a systems engineering approach

    Directory of Open Access Journals (Sweden)

    Ferreira, Tremaine

    2016-08-01

    Full Text Available Automated guided vehicles (AGVs are widely used for transporting materials in industry and commerce. In this research, an intelligent AGV-based material-handling system was developed using a model- based systems engineering (MBSE approach. The core of the AGV, the controller, was designed in the system modelling language environment using Visual Paradigm software, and then implemented in the hardware. As the result, the AGV’s complex tasks of material handling, navigation, and communication were successfully accomplished and tested in the real industrial environment. The developed AGV is capable of towing trolleys with a weight of up to 200kg at walking speed. The AGV can be incorporated into an intelligent material-handling system with multiple autonomous vehicles and work stations, thus providing flexibility and reconfigurability for the whole manufacturing system. Ergonomic and safety aspects were also considered in the design of the AGV. A comprehensive safety system that is compliant with industrial standards was implemented.

  16. MLET: A Power Efficient Approach for TCAM Based, IP Lookup Engines in Internet Routers

    CERN Document Server

    Mahini, Hamidreza; Mahini, Alireza; 10.5121/ijcnc.2010.2302

    2010-01-01

    Routers are one of the important entities in computer networks specially the Internet. Forwarding IP packets is a valuable and vital function in Internet routers. Routers extract destination IP address from packets and lookup those addresses in their own routing table. This task is called IP lookup. Internet address lookup is a challenging problem due to the increasing routing table sizes. Ternary Content-Addressable Memories (TCAMs)are becoming very popular for designing high-throughput address lookup?engines on routers: they are fast, cost-effective and simple to manage. Despite the TCAMs speed, their high power consumption is their major drawback. In this paper, Multilevel Enabling Technique (MLET), a power efficient TCAM based hardware architecture has been proposed. This scheme is employed after an Espresso-II minimization algorithm to achieve lower power consumption. The performance evaluation of the proposed approach shows that it can save considerable amount of routing table's power consumption.

  17. A Semantic Query Transformation Approach Based on Ontology for Search Engine

    OpenAIRE

    SAJENDRA KUMAR; RAM KUMAR RANA; PAWAN SINGH

    2012-01-01

    These days we are using some popular web search engines for information retrieval in all areas, such engine are as Google, Yahoo!, and Live Search, etc. to obtain initial helpful information.Which information we retrieved via search engine may not be relevant to the search target in the search engine user's mind. When user not found relevant information he has to shortlist the results. Thesesearch engines use traditional search service based on "static keywords", which require the users to ty...

  18. Application of a Sensemaking Approach to Ethics Training in the Physical Sciences and Engineering

    Science.gov (United States)

    Kligyte, Vykinta; Marcy, Richard T.; Waples, Ethan P.; Sevier, Sydney T.; Godfrey, Elaine S.; Mumford, Michael D.; Hougen, Dean F.

    2008-06-01

    Integrity is a critical determinant of the effectiveness of research organizations in terms of producing high quality research and educating the new generation of scientists. A number of responsible conduct of research (RCR) training programs have been developed to address this growing organizational concern. However, in spite of a significant body of research in ethics training, it is still unknown which approach has the highest potential to enhance researchers' integrity. One of the approaches showing some promise in improving researchers' integrity has focused on the development of ethical decision-making skills. The current effort proposes a novel curriculum that focuses on broad metacognitive reasoning strategies researchers use when making sense of day-to-day social and professional practices that have ethical implications for the physical sciences and engineering. This sensemaking training has been implemented in a professional sample of scientists conducting research in electrical engineering, atmospheric and computer sciences at a large multi-cultural, multi-disciplinary, and multi-university research center. A pre-post design was used to assess training effectiveness using scenario-based ethical decision-making measures. The training resulted in enhanced ethical decision-making of researchers in relation to four ethical conduct areas, namely data management, study conduct, professional practices, and business practices. In addition, sensemaking training led to researchers' preference for decisions involving the application of the broad metacognitive reasoning strategies. Individual trainee and training characteristics were used to explain the study findings. Broad implications of the findings for ethics training development, implementation, and evaluation in the sciences are discussed.

  19. Colloidal gas aphron foams: A novel approach to a hydrogel based tissue engineered myocardial patch

    Science.gov (United States)

    Johnson, Elizabeth Edna

    Cardiovascular disease currently affects an estimated 58 million Americans and is the leading cause of death in the US. Over 2.3 million Americans are currently living with heart failure a leading cause of which is acute myocardial infarction, during which a part of the heart muscle is damaged beyond repair. There is a great need to develop treatments for damaged heart tissue. One potential therapy involves replacement of nonfunctioning scar tissue with a patch of healthy, functioning tissue. A tissue engineered cardiac patch would be ideal for such an application. Tissue engineering techniques require the use of porous scaffolds, which serve as a 3-D template for initial cell attachment and grow-th leading to tissue formation. The scaffold must also have mechanical properties closely matching those of the tissues at the site of implantation. Our research presents a new approach to meet these design requirements. A unique interaction between poly(vinyl alcohol) and amino acids has been discovered by our lab, resulting in the production of novel gels. These unique synthetic hydrogels along with one natural hydrogel, alginate (derived from brown seaweed), have been coupled with a new approach to tissue scaffold fabrication using solid colloidal gas aphrons (CGAs). CGAs are colloidal foams containing uniform bubbles with diameters on the order of micrometers. Upon solidification the GCAs form a porous, 3-D network suitable for a tissue scaffold. The project encompasses four specific aims: (I) characterize hydrogel formation mechanism, (II) use colloidal gas aphrons to produce hydrogel scaffolds, (III) chemically and physically characterize scaffold materials and (IV) optimize and evaluate scaffold biocompatibility.

  20. Understanding ill-structured engineering ethics problems through a collaborative learning and argument visualization approach.

    Science.gov (United States)

    Hoffmann, Michael; Borenstein, Jason

    2014-03-01

    As a committee of the National Academy of Engineering recognized, ethics education should foster the ability of students to analyze complex decision situations and ill-structured problems. Building on the NAE's insights, we report about an innovative teaching approach that has two main features: first, it places the emphasis on deliberation and on self-directed, problem-based learning in small groups of students; and second, it focuses on understanding ill-structured problems. The first innovation is motivated by an abundance of scholarly research that supports the value of deliberative learning practices. The second results from a critique of the traditional case-study approach in engineering ethics. A key problem with standard cases is that they are usually described in such a fashion that renders the ethical problem as being too obvious and simplistic. The practitioner, by contrast, may face problems that are ill-structured. In the collaborative learning environment described here, groups of students use interactive and web-based argument visualization software called "AGORA-net: Participate - Deliberate!". The function of the software is to structure communication and problem solving in small groups. Students are confronted with the task of identifying possible stakeholder positions and reconstructing their legitimacy by constructing justifications for these positions in the form of graphically represented argument maps. The argument maps are then presented in class so that these stakeholder positions and their respective justifications become visible and can be brought into a reasoned dialogue. Argument mapping provides an opportunity for students to collaborate in teams and to develop critical thinking and argumentation skills.

  1. Product design for energy reduction in concurrent engineering: An Inverted Pyramid Approach

    Science.gov (United States)

    Alkadi, Nasr M.

    on product, process, and system design parameters. In depth evaluation to how the design and manufacturing normally happen in concurrent engineering provided a framework to develop energy system levels in machining within the concurrent engineering environment using the method of "Inverted Pyramid Approach", (IPA). The IPA features varying levels of output energy based information depending on the input design parameters that is available during each stage (level) of the product design. The experimental work, the in-depth evaluation of design and manufacturing in CE, and the developed energy system levels in machining provided a solid base for the development of the model for the design for energy reduction in CE. The model was used to analyze an example part where 12 evolving designs were thoroughly reviewed to investigate the sensitivity of energy to design parameters in machining. The model allowed product design teams to address manufacturing energy concerns early during the design stage. As a result, ranges for energy sensitive design parameters impacting product manufacturing energy consumption were found in earlier levels. As designer proceeds to deeper levels in the model, this range tightens and results in significant energy reductions.

  2. A Structural Biology and Protein Engineering Approach to the Engineering Highly Proficient Catalytic Bioscavengers for In Vivo Detoxification of a Broad Spectrum of Nerve Agents

    Science.gov (United States)

    2016-06-30

    Final 7 Aug 2015-31 May 2016 4. TITLE AND SUBTITLE Sa. CONTRACT NUMBER A Structural Biology and Protein Engineering Approach to the HDTRA1-11-C...r ------------ DTVL OCR l ------------- OCRL OCRL ooooo!:"o-ftro ooo~o s 1 ~ 1 oi oo --- ------- oooooo! - Figure 2: Sequence alignment of PTE...computationally focused libraries. ACS chemical biology , 8 , 2394-2403 Davis IW, and D. Baker, 2009, Rosettaligand docking with full ligand and receptor

  3. A Model-Driven Engineering Approach to Develop a Cooperative Information System

    Directory of Open Access Journals (Sweden)

    Jean Michel Inglebert

    2013-06-01

    Full Text Available To reuse one or several existing systems in orderto develop a complex system isa common practice insoftware engineering. This approach can be justified by thefact that it is often difficult for a singleInformation System(IS to accomplish all the requested tasks. So, one solution isto combine many differentISs and make them collaboratein order to realize these tasks. We proposed anapproach named AspeCiS(An Aspect-oriented Approach toDevelop a Cooperative Information System to develop aCooperativeInformation System from existing ISs by usingtheir artifacts such as existing requirements, and design.AspeCiS covers the three following phases: (i discoveryand analysis of Cooperative Requirements, (iidesign ofCooperative Requirements models, and (iii preparation ofthe implementation phase. The mainissue of AspeCiS is thedefinition of Cooperative Requirements using the ExistingRequirements andAdditional Requirements, which shouldbe composed with Aspectual Requirements. We earlier studiedhowto elicit the Cooperative Requirements in AspeCiS(phase ofdiscoveryand analysis of CooperativeRequirementsin AspeCiS.We studyherethe second phase of AspeCiS(design ofCooperativeRequirements models, by the way of a model weavingprocess. This process uses so-called AspeCiSWeaving Metamodel, and it weaves Existing andAdditional Requirementsmodels to realize CooperativeRequirements models

  4. Metabolic engineering of lactic acid bacteria, the combined approach: kinetic modelling, metabolic control and experimental analysis.

    Science.gov (United States)

    Hoefnagel, Marcel H N; Starrenburg, Marjo J C; Martens, Dirk E; Hugenholtz, Jeroen; Kleerebezem, Michiel; Van Swam, Iris I; Bongers, Roger; Westerhoff, Hans V; Snoep, Jacky L

    2002-04-01

    Everyone who has ever tried to radically change metabolic fluxes knows that it is often harder to determine which enzymes have to be modified than it is to actually implement these changes. In the more traditional genetic engineering approaches 'bottle-necks' are pinpointed using qualitative, intuitive approaches, but the alleviation of suspected 'rate-limiting' steps has not often been successful. Here the authors demonstrate that a model of pyruvate distribution in Lactococcus lactis based on enzyme kinetics in combination with metabolic control analysis clearly indicates the key control points in the flux to acetoin and diacetyl, important flavour compounds. The model presented here (available at http://jjj.biochem.sun.ac.za/wcfs.html) showed that the enzymes with the greatest effect on this flux resided outside the acetolactate synthase branch itself. Experiments confirmed the predictions of the model, i.e. knocking out lactate dehydrogenase and overexpressing NADH oxidase increased the flux through the acetolactate synthase branch from 0 to 75% of measured product formation rates.

  5. An information-based rough set approach to critical engineering factor identification

    Institute of Scientific and Technical Information of China (English)

    Jing Ji; Zheng Dongjian

    2008-01-01

    In order to analyze the main critical engineering factors, an information-based rough set approach that considers conditional information entropy as a measurement of information has been developed. An algorithm for continuous attribute discretization based on conditional information entropy and an algorithm for rule extraction considering the supports of rules are proposed. The initial decision system is established by collecting enough monitoring data. Then, the continuous attributes are discretized, and the condition attributes are reduced. Finally, the rules that indicate the action law of the main factors are extracted and the results are explained. By applying this approach to a crack in an arch gravity dam, it can be concluded that the water level and the temperature are the main factors affecting the crack opening, and there is a negative correlation between the crack opening and the temperature. This conclusion corresponds with the observation that cracks in most concrete dams are influenced mainly by water level and temperature, and the influence of temperature is more evident.

  6. A Hybrid PCA-CART-MARS-Based Prognostic Approach of the Remaining Useful Life for Aircraft Engines

    Directory of Open Access Journals (Sweden)

    Fernando Sánchez Lasheras

    2015-03-01

    Full Text Available Prognostics is an engineering discipline that predicts the future health of a system. In this research work, a data-driven approach for prognostics is proposed. Indeed, the present paper describes a data-driven hybrid model for the successful prediction of the remaining useful life of aircraft engines. The approach combines the multivariate adaptive regression splines (MARS technique with the principal component analysis (PCA, dendrograms and classification and regression trees (CARTs. Elements extracted from sensor signals are used to train this hybrid model, representing different levels of health for aircraft engines. In this way, this hybrid algorithm is used to predict the trends of these elements. Based on this fitting, one can determine the future health state of a system and estimate its remaining useful life (RUL with accuracy. To evaluate the proposed approach, a test was carried out using aircraft engine signals collected from physical sensors (temperature, pressure, speed, fuel flow, etc.. Simulation results show that the PCA-CART-MARS-based approach can forecast faults long before they occur and can predict the RUL. The proposed hybrid model presents as its main advantage the fact that it does not require information about the previous operation states of the input variables of the engine. The performance of this model was compared with those obtained by other benchmark models (multivariate linear regression and artificial neural networks also applied in recent years for the modeling of remaining useful life. Therefore, the PCA-CART-MARS-based approach is very promising in the field of prognostics of the RUL for aircraft engines.

  7. A Hybrid PCA-CART-MARS-Based Prognostic Approach of the Remaining Useful Life for Aircraft Engines

    Science.gov (United States)

    Lasheras, Fernando Sánchez; Nieto, Paulino José García; de Cos Juez, Francisco Javier; Bayón, Ricardo Mayo; Suárez, Victor Manuel González

    2015-01-01

    Prognostics is an engineering discipline that predicts the future health of a system. In this research work, a data-driven approach for prognostics is proposed. Indeed, the present paper describes a data-driven hybrid model for the successful prediction of the remaining useful life of aircraft engines. The approach combines the multivariate adaptive regression splines (MARS) technique with the principal component analysis (PCA), dendrograms and classification and regression trees (CARTs). Elements extracted from sensor signals are used to train this hybrid model, representing different levels of health for aircraft engines. In this way, this hybrid algorithm is used to predict the trends of these elements. Based on this fitting, one can determine the future health state of a system and estimate its remaining useful life (RUL) with accuracy. To evaluate the proposed approach, a test was carried out using aircraft engine signals collected from physical sensors (temperature, pressure, speed, fuel flow, etc.). Simulation results show that the PCA-CART-MARS-based approach can forecast faults long before they occur and can predict the RUL. The proposed hybrid model presents as its main advantage the fact that it does not require information about the previous operation states of the input variables of the engine. The performance of this model was compared with those obtained by other benchmark models (multivariate linear regression and artificial neural networks) also applied in recent years for the modeling of remaining useful life. Therefore, the PCA-CART-MARS-based approach is very promising in the field of prognostics of the RUL for aircraft engines. PMID:25806876

  8. A hybrid PCA-CART-MARS-based prognostic approach of the remaining useful life for aircraft engines.

    Science.gov (United States)

    Sánchez Lasheras, Fernando; García Nieto, Paulino José; de Cos Juez, Francisco Javier; Mayo Bayón, Ricardo; González Suárez, Victor Manuel

    2015-03-23

    Prognostics is an engineering discipline that predicts the future health of a system. In this research work, a data-driven approach for prognostics is proposed. Indeed, the present paper describes a data-driven hybrid model for the successful prediction of the remaining useful life of aircraft engines. The approach combines the multivariate adaptive regression splines (MARS) technique with the principal component analysis (PCA), dendrograms and classification and regression trees (CARTs). Elements extracted from sensor signals are used to train this hybrid model, representing different levels of health for aircraft engines. In this way, this hybrid algorithm is used to predict the trends of these elements. Based on this fitting, one can determine the future health state of a system and estimate its remaining useful life (RUL) with accuracy. To evaluate the proposed approach, a test was carried out using aircraft engine signals collected from physical sensors (temperature, pressure, speed, fuel flow, etc.). Simulation results show that the PCA-CART-MARS-based approach can forecast faults long before they occur and can predict the RUL. The proposed hybrid model presents as its main advantage the fact that it does not require information about the previous operation states of the input variables of the engine. The performance of this model was compared with those obtained by other benchmark models (multivariate linear regression and artificial neural networks) also applied in recent years for the modeling of remaining useful life. Therefore, the PCA-CART-MARS-based approach is very promising in the field of prognostics of the RUL for aircraft engines.

  9. The reversal of diabetes in rat model using mouse insulin producing cells - a combination approach of tissue engineering and macroencapsulation.

    Science.gov (United States)

    Muthyala, Sudhakar; Raj, V R Rana; Mohanty, Mira; Mohanan, P V; Nair, Prabha D

    2011-05-01

    Type 1 diabetes is a chronic disorder resulting from the autoimmune destruction of insulin-producing cells, a leading cause of morbidity and mortality all over the world. In this study a tissue engineering approach was compared with a macroencapsulation approach to reverse type 1 diabetes in a rat model, using mouse pancreatic progenitor cell (PPC)-derived islet-like clusters and mouse islets. For the tissue engineering approach the cells were cultured on gelatin scaffolds cross-linked with EDC in the presence of polyvinylpyrrolidone in vitro (GPE scaffolds), while for the macroencapsulation approach the cells were encapsulated in polyurethane-polyvinylpyrrolidone semi-interpenetrating networks. In the combination approach the cells cultured on GPE scaffolds were further encapsulated in a polyurethane-polyvinylpyrrolidone capsule. Real time PCR studies and the glucose challenge assay have shown that cells on GPE scaffolds could express and secrete insulin and glucagon in vitro. However, under in vivo conditions the animals treated by the tissue engineering approach died within 15-20 days and showed no reversal of their diabetes, due to infiltration of immune cells such as CD4 and CD8 cells and macrophages. In the macroencapsulation approach the animals showed euglycemia within 25 days, which was maintained for further 20 days, but after that the animals died. Interestingly, in the combination approach the animals showed reversal of hyperglycemia, and remained euglycemic for up to 3 months. The time needed to achieve initial euglycemia was different with different cell types, i.e. the combination approach with mouse islets achieved euglycemia within 15 days, whereas with PPC-derived islet-like clusters euglycemia was achieved within 25 days. This study confirmed that a combination of tissue engineering and macroencapsulation with mouse islets could reverse diabetes and maintain euglycemia in an experimental diabetes rat model for 90 days.

  10. Bayesian approaches to reverse engineer cellular systems: a simulation study on nonlinear Gaussian networks

    Directory of Open Access Journals (Sweden)

    Ramoni Marco F

    2007-05-01

    Full Text Available Abstract Background Reverse engineering cellular networks is currently one of the most challenging problems in systems biology. Dynamic Bayesian networks (DBNs seem to be particularly suitable for inferring relationships between cellular variables from the analysis of time series measurements of mRNA or protein concentrations. As evaluating inference results on a real dataset is controversial, the use of simulated data has been proposed. However, DBN approaches that use continuous variables, thus avoiding the information loss associated with discretization, have not yet been extensively assessed, and most of the proposed approaches have dealt with linear Gaussian models. Results We propose a generalization of dynamic Gaussian networks to accommodate nonlinear dependencies between variables. As a benchmark dataset to test the new approach, we used data from a mathematical model of cell cycle control in budding yeast that realistically reproduces the complexity of a cellular system. We evaluated the ability of the networks to describe the dynamics of cellular systems and their precision in reconstructing the true underlying causal relationships between variables. We also tested the robustness of the results by analyzing the effect of noise on the data, and the impact of a different sampling time. Conclusion The results confirmed that DBNs with Gaussian models can be effectively exploited for a first level analysis of data from complex cellular systems. The inferred models are parsimonious and have a satisfying goodness of fit. Furthermore, the networks not only offer a phenomenological description of the dynamics of cellular systems, but are also able to suggest hypotheses concerning the causal interactions between variables. The proposed nonlinear generalization of Gaussian models yielded models characterized by a slightly lower goodness of fit than the linear model, but a better ability to recover the true underlying connections between

  11. A Biofilm Treatment Approach for Produced Water from Hydraulic Fracturing Using Engineered Microbial Mats

    Science.gov (United States)

    Akyon, B.; Stachler, E.; Bibby, K. J.

    2015-12-01

    Hydraulic fracturing results in large volumes of wastewater, called "produced water". Treatment of produced water is challenged by its high salt, organic compound, and radionuclide concentrations. Current disposal approaches include deep well injection and physical-chemical treatment for surface disposal; however, deep well injection has been recently linked to induced seismicity and physical-chemical treatments suffer from fouling and high cost. The reuse of the produced water has emerged as a desirable management option; however, this requires pretreatment to generate a water of usable quality and limit microbial activity. Biological treatment is an underexplored area in produced water management and has the potential to remove organics and reduce overall costs for physiochemical treatment or reuse. Suspended growth biological treatment techniques are known to be limited by salinity motivating a more robust biofilm approach: 'microbial mats'. In this study, we used engineered microbial mats as a biofilm treatment for the produced water. Evaluation of the biodegradation performance of microbial mats in synthetic and real produced waters showed microbial activity at up to 100,000 mg/L TDS concentration (three times the salt concentration of the ocean). Organic removal rates reached to 1.45 mg COD/gramwet-day at 91,351 mg/L TDS in real produced water samples and initial evaluation demonstrated the potential for field-scale application. Metagenomic analyses of microbial mats demonstrated an adaptive shift in the microbial community treating different samples, suggesting the wide applicability of this treatment approach for produced waters with varying chemical composition. On-going studies focus on the evaluation of the removal of the organics and the contaminants of high concern in produced water using microbial mats as well as the effect of the biofilm growth conditions on the biodegradation in changing salt concentrations.

  12. Noise data for a twin-engine commercial jet aircraft flying conventional, steep, and two-segment approaches

    Science.gov (United States)

    Hastings, E. C., Jr.; Mueller, A. W.; Hamilton, J. R.

    1977-01-01

    Center-line noise measurements of a twin-engine commercial jet aircraft were made during steep landing approach profiles, and during two-segment approach profiles for comparison with similar measurements made during conventional approaches. The steep and two-segment approaches showed significant noise reductions when compared with the -3 deg base line. The measured noise data were also used to develop a method for estimating the noise under the test aircraft at thrust and altitude conditions typical of current landing procedures and of landing procedures under development for the Advanced Air Traffic Control System.

  13. A Grounded Theory Approach: Conceptions of Understanding in Engineering Mathematics Learning

    Science.gov (United States)

    Khiat, Henry

    2010-01-01

    Mathematics is of utmost importance in engineering courses but studies on engineering students' conceptions of understanding in mathematics learning are found lacking in the literature. Therefore, this research attempts to address the above issue by answering the research question: "What are engineering students' conceptions of understanding…

  14. An uncoupled multiphase approach towards modeling ice crystals in jet engines

    Science.gov (United States)

    Nilamdeen, Mohamed Shezad

    A recent series of high altitude turbofan engine malfunctions, characterized by flameout and sudden power losses have been reported in recent years. The source of these incidents has been hypothesized to be due to the presence of ice crystals at high altitudes. Ice crystals have been shown to have ballistic trajectories and consequently enter the core engine flow, without getting centrifuged out towards the engine bypass as droplets do. The crystals may melt as they move downstream to higher temperatures in successive stages, or hit a heated surface. The wetted surface may then act as an interface for further crystal impingement, which locally reduces the temperature and could lead to an ice accretion on the components. Ice can accrete to dangerously high levels, causing compressor surge due to blockage of the primary flowpath, vibrational instabilities due to load imbalances of ice on rotating components, mechanical damage of components downstream due to large shed ice fragments, or performance losses if ice enters the combustor, causing a decreased burner efficiency and an eventual flame-out. In order to provide a numerical tool to analyze such situations, FENSAP-ICE has been extended to model mixed-phase flows that combine air, water and ice crystals, and the related ice accretion. DROP3D has been generalized to calculate particle impingement, concentration, and field velocities in an uncoupled approach that neglects any phase change by assuming both ice crystals and supercooled droplets are in thermodynamic equilibrium. ICE3D then accounts for the contribution of ice crystals that stick and melt on an existing water-film and promote ice accretion. The extended ice crystal impingement and ice accretion model has been validated against test data from Cox and Co. and National Research Council icing tests conducted on a NACA0012 airfoil and unheated non-rotating cylinder respectively. The tests show a consistent agreement with respect to experimental profiles in

  15. Approaches to Curriculum and Teaching Materials to Bring Out Better Skilled Software Engineers-An Indian Perspective

    CERN Document Server

    Padmini, H A; Nair, T R Gopalakrishnan

    2010-01-01

    Development of Curriculum and delivery materials has undergone changes over a period of time, in undergraduate engineering degree system in Indian universities. However, there exists a gap between industry expectations in IT field and skills and knowledge that the graduating engineers possess and this continues to grow. A similar situation has been seen in the developed countries like USA, UK and Australia. Several researchers and practitioners have discussed and tried to come up with innovative approaches to teaching software engineering and IT as a whole. In India, it is of vital importance that steps be taken to address this issue seriously. This paper discusses some of the measures that have been implemented so that this gap is reduced and software engineers with better skills are produced. Changes to curriculum, industry-academia collaboration through conferences, sabbaticals etc., industry internships and live projects for final year students are some of the measures that have been discussed in this pap...

  16. A bottom up approach for engineering catchments through sustainable runoff management

    Science.gov (United States)

    Wilkinson, M.; Quinn, P. F.; Jonczyk, J.; Burke, S.

    2010-12-01

    There is no doubt that our catchments are under great stress. There have been many accounts around the world of severe flood events and water quality issues within channels. As a result of these, ecological habitats in rivers are also under pressure. Within the United Kingdom, all these issues have been identified as key target areas for policy. Traditionally this has been managed by a policy driven top down approach which is usually ineffective. A one ‘size fits all’ attitude often does not work. This paper presents a case study in northern England whereby a bottom up approach is applied to multipurpose managing of catchments at the source (in the order of 1-10km2). This includes simultaneous tackling of water quality, flooding and ecological issues by creating sustainable runoff management solutions such as storage ponds, wetlands, beaver dams and willow riparian features. In order to identify the prevailing issues in a specific catchment, full and transparent stakeholder engagement is essential, with everybody who has a vested interest in the catchment being involved from the beginning. These problems can then be dealt with through the use of a novel catchment management toolkit, which is transferable to similar scale catchments. However, evidence collected on the ground also allows for upscaling of the toolkit. The process gathers the scientific evidence about the effectiveness of existing or new measures, which can really change the catchment functions. Still, we need to get better at communicating the science to policy makers and policy therefore must facilitate a bottom up approach to land and water management. We show a test site for this approach in the Belford burn catchment (6km2), northern England. This catchment has problems with flooding and water quality. Increased sediment loads are affecting the nearby estuary which is an important ecological zone and numerous floods have affected the local village. A catchment engineering toolkit has been

  17. An overview of three promising mechanical, optical, and biochemical engineering approaches to improve selective photothermolysis of refractory port wine stains.

    Science.gov (United States)

    Aguilar, Guillermo; Choi, Bernard; Broekgaarden, Mans; Yang, Owen; Yang, Bruce; Ghasri, Pedram; Chen, Jennifer K; Bezemer, Rick; Nelson, J Stuart; van Drooge, Anne Margreet; Wolkerstorfer, Albert; Kelly, Kristen M; Heger, Michal

    2012-02-01

    During the last three decades, several laser systems, ancillary technologies, and treatment modalities have been developed for the treatment of port wine stains (PWSs). However, approximately half of the PWS patient population responds suboptimally to laser treatment. Consequently, novel treatment modalities and therapeutic techniques/strategies are required to improve PWS treatment efficacy. This overview therefore focuses on three distinct experimental approaches for the optimization of PWS laser treatment. The approaches are addressed from the perspective of mechanical engineering (the use of local hypobaric pressure to induce vasodilation in the laser-irradiated dermal microcirculation), optical engineering (laser-speckle imaging of post-treatment flow in laser-treated PWS skin), and biochemical engineering (light- and heat-activatable liposomal drug delivery systems to enhance the extent of post-irradiation vascular occlusion).

  18. Impacts of light shading and nutrient enrichment geo-engineering approaches on the productivity of a stratified, oligotrophic ocean ecosystem.

    Science.gov (United States)

    Hardman-Mountford, Nick J; Polimene, Luca; Hirata, Takafumi; Brewin, Robert J W; Aiken, Jim

    2013-12-06

    Geo-engineering proposals to mitigate global warming have focused either on methods of carbon dioxide removal, particularly nutrient fertilization of plant growth, or on cooling the Earth's surface by reducing incoming solar radiation (shading). Marine phytoplankton contribute half the Earth's biological carbon fixation and carbon export in the ocean is modulated by the actions of microbes and grazing communities in recycling nutrients. Both nutrients and light are essential for photosynthesis, so understanding the relative influence of both these geo-engineering approaches on ocean ecosystem production and processes is critical to the evaluation of their effectiveness. In this paper, we investigate the relationship between light and nutrient availability on productivity in a stratified, oligotrophic subtropical ocean ecosystem using a one-dimensional water column model coupled to a multi-plankton ecosystem model, with the goal of elucidating potential impacts of these geo-engineering approaches on ecosystem production. We find that solar shading approaches can redistribute productivity in the water column but do not change total production. Macronutrient enrichment is able to enhance the export of carbon, although heterotrophic recycling reduces the efficiency of carbon export substantially over time. Our results highlight the requirement for a fuller consideration of marine ecosystem interactions and feedbacks, beyond simply the stimulation of surface blooms, in the evaluation of putative geo-engineering approaches.

  19. Introducing a Transdisciplinary Approach in Studies regarding Risk Assessment and Management in Educational Programs for Environmental Engineers and Planners

    Science.gov (United States)

    Menoni, Scira

    2006-01-01

    Purpose: The purpose of this paper is to discuss how long term risk prevention and civil protection may enter in university programs for environmental engineers and urban and regional planners. Design/methodology/approach: First the distinction between long term risk prevention and emergency preparedness is made, showing that while the first has…

  20. Using an Evidential Reasoning Approach for Portfolio Assessments in a Project-Based Learning Engineering Design Course

    Science.gov (United States)

    Jaeger, Martin; Adair, Desmond

    2015-01-01

    The purpose of this study is to analyse the feasibility of an evidential reasoning (ER) method for portfolio assessments and comparison of the results found with those based on a traditional holistic judgement. An ER approach has been incorporated into portfolio assessment of an undergraduate engineering design course delivered as a project-based…

  1. The Insertion of Environmental Contents in the Engineering Teaching: A Tentative Approach at the UFMG, Belo Horizonte, Brazil.

    Science.gov (United States)

    Bandeira de Melo, Gilberto C.; Pinto, Joana Darc da Silva

    In this work a tentative approach is described, with the intent of an optimized insertion of the environmental contents in engineering courses, using the existing disciplines, and with a minimal, if any, increase of the disciplines related to environmental protection. The disciplines are firstly classified with regard to the environmental issues…

  2. Incorporating a Systems Approach into Civil and Environmental Engineering Curricula: Effect on Course Redesign, and Student and Faculty Attitudes

    Science.gov (United States)

    Hayden, Nancy J.; Rizzo, Donna M.; Dewoolkar, Mandar M.; Neumann, Maureen D.; Lathem, Sandra; Sadek, Adel

    2011-01-01

    This paper presents a brief overview of the changes made during our department level reform (DLR) process (Grant Title: "A Systems Approach for Civil and Environmental Engineering Education: Integrating Systems Thinking, Inquiry-Based Learning and Catamount Community Service-Learning Projects") and some of the effects of these changes on…

  3. Strengthening the link between theory and practice in teaching design engineering: an empirical study on a new approach

    NARCIS (Netherlands)

    Tempelman, E.; Pilot, A.

    2010-01-01

    In 2007, the Faculty of Industrial Design Engineering of the Delft University of Technology introduced a new bachelor program. Based on theories of learning and instruction three design principles were used to develop an approach that aims to make it easier for students to bridge the gap between the

  4. A user-centered, iterative engineering approach for advanced biomass cookstove design and development

    Science.gov (United States)

    Shan, Ming; Carter, Ellison; Baumgartner, Jill; Deng, Mengsi; Clark, Sierra; Schauer, James J.; Ezzati, Majid; Li, Jiarong; Fu, Yu; Yang, Xudong

    2017-09-01

    Unclean combustion of solid fuel for cooking and other household energy needs leads to severe household air pollution and adverse health impacts in adults and children. Replacing traditional solid fuel stoves with high efficiency, low-polluting semi-gasifier stoves can potentially contribute to addressing this global problem. The success of semi-gasifier cookstove implementation initiatives depends not only on the technical performance and safety of the stove, but also the compatibility of the stove design with local cooking practices, the needs and preferences of stove users, and community economic structures. Many past stove design initiatives have failed to address one or more of these dimensions during the design process, resulting in failure of stoves to achieve long-term, exclusive use and market penetration. This study presents a user-centered, iterative engineering design approach to developing a semi-gasifier biomass cookstove for rural Chinese homes. Our approach places equal emphasis on stove performance and meeting the preferences of individuals most likely to adopt the clean stove technology. Five stove prototypes were iteratively developed following energy market and policy evaluation, laboratory and field evaluations of stove performance and user experience, and direct interactions with stove users. The most current stove prototype achieved high performance in the field on thermal efficiency (ISO Tier 3) and pollutant emissions (ISO Tier 4), and was received favorably by rural households in the Sichuan province of Southwest China. Among household cooks receiving the final prototype of the intervention stove, 88% reported lighting and using it at least once. At five months post-intervention, the semi-gasifier stoves were used at least once on an average of 68% [95% CI: 43, 93] of days. Our proposed design strategy can be applied to other stove development initiatives in China and other countries.

  5. Eco-innovative design approach: Integrating quality and environmental aspects in prioritizing and solving engineering problems

    Science.gov (United States)

    Chakroun, Mahmoud; Gogu, Grigore; Pacaud, Thomas; Thirion, François

    2014-09-01

    This study proposes an eco-innovative design process taking into consideration quality and environmental aspects in prioritizing and solving technical engineering problems. This approach provides a synergy between the Life Cycle Assessment (LCA), the nonquality matrix, the Theory of Inventive Problem Solving (TRIZ), morphological analysis and the Analytical Hierarchy Process (AHP). In the sequence of these tools, LCA assesses the environmental impacts generated by the system. Then, for a better consideration of environmental aspects, a new tool is developed, the non-quality matrix, which defines the problem to be solved first from an environmental point of view. The TRIZ method allows the generation of new concepts and contradiction resolution. Then, the morphological analysis offers the possibility of extending the search space of solutions in a design problem in a systematic way. Finally, the AHP identifies the promising solution(s) by providing a clear logic for the choice made. Their usefulness has been demonstrated through their application to a case study involving a centrifugal spreader with spinning discs.

  6. Problem Solution Processes of Musicians and Engineers: What do Their Approaches Look Like

    Directory of Open Access Journals (Sweden)

    Säde-Pirkko Nissilä

    2015-06-01

    Full Text Available PBL is learning through becoming conscious of practical and abstract problems and finding ways how to solve them. It can be a pattern which doesn’t follow traditional divisions of disciplines. In this article the material was collected from two, in the first sight, very different groups. One was music students (N = 62 who had to learn to solve various practical and theoretical problems in preparing a program for a series of concerts as collective and individual action. The method used was the 7-step method which divides learning into seven phases proceeding from creating the social frame of reference and mental models (steps 1–4 through actual work (steps 5–6 to the evaluation of the outcomes (step 7. Another group consisted of international, multicultural business leaders in engineering (N = 6. In using earlier the 7-step method, the approaches resembled those of the music students: deepening their professional competences. To engage their ability to use imagination and connect reality with brainstorming and mental flexibility, the creative PBL method 635 was used. Three practical problems were solved so that the solutions included new viewpoints which would be applied to meet the real needs in the near future. The results show that not only were the learning targets of both groups reached but, with reflection included, the processes widened the professional competences of the participants.

  7. Cross-disciplinary problem-solving workshop: a pedagogical approach to anticipate ergonomist engineering design collaboration.

    Science.gov (United States)

    Brunier, Elisabeth; Le Chapellier, Michel; Dejean, Pierre Henri

    2012-01-01

    The aims of this paper are to present concept and results of an innovative educational model approach based on ergonomics involvement in industrial project. First we present Cross disciplinary Problem solving Workshop by answering three questions:1) What is a CPW: A partnership between Universities and one or several companies, purposes of it are first to increase health, well being, companies teams competencies, and competitiveness, second to train the "IPOD generation" to include risks prevention in design. 2) How does it work? CPW allows cooperation between experience and new insight through inductive methods. This model follows the Piaget (1) philosophy linking concrete world to abstraction by a learning system associating realization and abstraction. 3) Is it successful? In order to answer this third question we will show examples of studies and models performed during CPWs.It appears that the CPWs produce visible results in companies such as new process designs, new methods, and also changes in lectures. However some less visible results remain unclear: How the company personnel evolve during and after CPW? Does CPW motivate our future engineers enough to continuously improve their skills in risk prevention and innovative design?

  8. Tissue Engineering Approaches to Cell-Based Type 1 Diabetes Therapy

    Science.gov (United States)

    Amer, Luke D.; Mahoney, Melissa J.

    2014-01-01

    Type 1 diabetes mellitus is an autoimmune disease resulting from the destruction of insulin-producing pancreatic β-cells. Cell-based therapies, involving the transplantation of functional β-cells into diabetic patients, have been explored as a potential long-term treatment for this condition; however, success is limited. A tissue engineering approach of culturing insulin-producing cells with extracellular matrix (ECM) molecules in three-dimensional (3D) constructs has the potential to enhance the efficacy of cell-based therapies for diabetes. When cultured in 3D environments, insulin-producing cells are often more viable and secrete more insulin than those in two dimensions. The addition of ECM molecules to the culture environments, depending on the specific type of molecule, can further enhance the viability and insulin secretion. This review addresses the different cell sources that can be utilized as β-cell replacements, the essential ECM molecules for the survival of these cells, and the 3D culture techniques that have been used to benefit cell function. PMID:24417705

  9. Modeling of high-temperature treatment of wood using the reaction engineering approach (REA).

    Science.gov (United States)

    Putranto, Aditya; Chen, Xiao Dong; Xiao, Zongyuan; Webley, Paul A

    2011-05-01

    A simple and accurate model of high-temperature treatment of wood can assist in the process design and the evaluation of performance of equipment. The high-temperature treatment of wood is essentially a drying process under linearly-increased gas temperature up to final temperature of 220-230°C which is a challenging process to model. This study is aimed to assess the applicability and accuracy of the reaction engineering approach (REA) to model the heat treatment of wood. In order to describe the process using the REA, the maximum activation energy (ΔE(v,b)) is evaluated according to the corresponding external conditions during the heat treatment. Results indicate that the REA coupled with the heat balance describes both moisture content and temperature profiles during the heat treatment very well. A good agreement towards the experimental data is indicated. It has also been shown that the current model is highly comparable in accuracy with the complex models.

  10. Approaches to the safety assessment of engineered nanomaterials (ENM) in food.

    Science.gov (United States)

    Cockburn, Andrew; Bradford, Roberta; Buck, Neil; Constable, Anne; Edwards, Gareth; Haber, Bernd; Hepburn, Paul; Howlett, John; Kampers, Frans; Klein, Christoph; Radomski, Marek; Stamm, Hermann; Wijnhoven, Susan; Wildemann, Tanja

    2012-06-01

    A systematic, tiered approach to assess the safety of engineered nanomaterials (ENMs) in foods is presented. The ENM is first compared to its non-nano form counterpart to determine if ENM-specific assessment is required. Of highest concern from a toxicological perspective are ENMs which have potential for systemic translocation, are insoluble or only partially soluble over time or are particulate and bio-persistent. Where ENM-specific assessment is triggered, Tier 1 screening considers the potential for translocation across biological barriers, cytotoxicity, generation of reactive oxygen species, inflammatory response, genotoxicity and general toxicity. In silico and in vitro studies, together with a sub-acute repeat-dose rodent study, could be considered for this phase. Tier 2 hazard characterisation is based on a sentinel 90-day rodent study with an extended range of endpoints, additional parameters being investigated case-by-case. Physicochemical characterisation should be performed in a range of food and biological matrices. A default assumption of 100% bioavailability of the ENM provides a 'worst case' exposure scenario, which could be refined as additional data become available. The safety testing strategy is considered applicable to variations in ENM size within the nanoscale and to new generations of ENM.

  11. Approaches to Affective Computing and Learning towards Interactive Decision Making in Process Control Engineering

    Institute of Scientific and Technical Information of China (English)

    SU Chong; LI Hong-Guang

    2013-01-01

    Numerous multi-objective decision-making problems related to industrial process control engineering such as control and operation performance evaluation are being resolved through human-computer interactions.With regard to the problems that traditional interactive evolutionary computing approaches suffer i.e.,limited searching ability and human's strong subjectivity in multi-objective-attribute decision-making,a novel affective computing and learning solution adapted to human-computer interaction mechanism is explicitly proposed.Therein,a kind of stimulating response based affective computing model (STAM) is constructed,along with quantitative relations between affective space and human's subjective preferences.Thereafter,affective learning strategies based on genetic algorithms are introduced which are responsible for gradually grasping essentials in human's subjective judgments in decision-making,reducing human's subjective fatigue as well as making the decisions more objective and scientific.Affective learning algorithm's complexity and convergence analysis are shown in Appendices A and B.To exemplify applications of the proposed methods,ad-hoc test functions and PID parameter tuning are suggested as case studies,giving rise to satisfying results and showing validity of the contributions.

  12. Design of experiments approach to engineer cell-secreted matrices for directing osteogenic differentiation.

    Science.gov (United States)

    Decaris, Martin L; Leach, J Kent

    2011-04-01

    The presentation of extracellular matrix (ECM) proteins provides an opportunity to instruct the phenotype and behavior of responsive cells. Decellularized cell-secreted matrix coatings (DM) represent a biomimetic culture surface that retains the complexity of the natural ECM. Microenvironmental culture conditions alter the composition of these matrices and ultimately the ability of DMs to direct cell fate. We employed a design of experiments (DOE) multivariable analysis approach to determine the effects and interactions of four variables (culture duration, cell seeding density, oxygen tension, and media supplementation) on the capacity of DMs to direct the osteogenic differentiation of human mesenchymal stem cells (hMSCs). DOE analysis revealed that matrices created with extended culture duration, ascorbate-2-phosphate supplementation, and in ambient oxygen tension exhibited significant correlations with enhanced hMSC differentiation. We validated the DOE model results using DMs predicted to have superior (DM1) or lesser (DM2) osteogenic potential for naïve hMSCs. Compared to cells on DM2, hMSCs cultured on DM1 expressed 2-fold higher osterix levels and deposited 3-fold more calcium over 3 weeks. Cells on DM1 coatings also exhibited greater proliferation and viability compared to DM2-coated substrates. This study demonstrates that DOE-based analysis is a powerful tool for optimizing engineered systems by identifying significant variables that have the greatest contribution to the target output.

  13. Genetic engineering represents a safe approach for innovations improving nutritional contents of major food crops

    Directory of Open Access Journals (Sweden)

    Werner Arber

    2017-05-01

    Full Text Available About 70 years ago early microbial genetic research revealed that inherited phenotypic traits become determined by DNA filaments composed of 4 different nucleotides that are linearly arranged. In the meantime we know that genes, the determinants of specific life functions, are genomic segments of an average size of about 1000 nucleotides, i.e. a very small part of a genome. Fundamental insights into the structures and functions of selected genes can be reached by sorting out the relevant short DNA segment, splicing this fragment into a natural gene vector such as a viral genome or a fertility plasmid. This allows the researchers to transfer the genetic hybrid into an appropriate host cell in order to produce many copies that can then serve for functional and structural analysis. This research approach became efficient in the 1970s. On the request of involved researchers, safety guidelines became proposed 1975 at the Asilomar Conference on Recombinant DNA (Berg, Baltimore, Brenner, Roblin, & Singer, 1975, then generally introduced and still largely followed nowadays. Carefully carried out genetic engineering by horizontally transferring a selected and functionally well known DNA segment into the genome of another organism has in many published biosafety investigations never shown any unexpected harmful effect. We will present below selected examples of research contributions enabling innovations for the benefit of human life conditions.

  14. A knowledge engineering approach for improving secondary recovery in offshore reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, Milton P.; Tovar, Felipe T.R.; Guerra, Fabio A. [Parana Institute of Technology (TECPAR), Curitiba, PR (Brazil). Artificial Intelligence Div.; Andrade, Cynthia; Baptista, Walmar [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas. Tecnologia de Materiais, Equipamentos e Corrosao

    2004-07-01

    Secondary recovery in offshore petroleum reservoirs by seawater injection is a technique traditionally applied in oil and gas industry. However, the injected water quality must be compatible with the reservoir characteristics in order to prevent corrosion, formation plugging and reservoir souring. So, the seawater must be treated before injection in the reservoirs and on-line monitoring equipment are employed to check the treatments efficacy. Nevertheless, the amount of data to analyze is quite big and involves many different experts, which make their evaluation and the establishment of correlations very difficult. For these cases, where it's crucial to detect the contaminants presence as soon as they occur to indicate corrective procedures, the application of knowledge engineering techniques and the development of expert systems are a good solution proposal. This paper presents the expert system InjeX (heuristic approach), developed for seawater injection treatment plants to maintain the water quality in offshore platforms. The description and the analysis of the problem, a proposed solution and some preliminary results are detailed and discussed along the paper. (author)

  15. An engineering approach to dry friction behaviour of numerous engineering plastics with respect to the mechanical properties

    Directory of Open Access Journals (Sweden)

    G. Kalacska

    2013-02-01

    Full Text Available Twenty-one different commercial-grade engineering polymers, including virgin and composite types, were selected for testing, based on mechanical engineering practices. Three groups were formed according to typical applications: 1 Sliding machine element materials; 2 Mechanically load-carrying machine element materials that are often subjected to friction and wear effects; and 3 Additional two amorphous materials used as chemically resistant materials that have rare sliding load properties. The friction running-in state was tested using a dynamic pin-on-plate test rig. During steady-state friction tests, two pv regimes (0.8 and 2 MPa"ms–1 were analysed by a pin-on-disc test system. Based on the measured forces on ground structural steel, surface friction coefficients were calculated and analysed with respect to the mechanical effects of friction. The friction results were evaluated by the measured mechanical properties: yield stress, Shore D hardness, Young’s modulus and elongation at the break. The three material groups exhibited different trends in friction with respect to changing mechanical properties. Linear (with varying positive and negative slopes, logarithmic and exponential relationships were observed, and occasionally there were no effects observed. At steady-state friction, the elongation at the break had less effect on the friction coefficients. The dynamic sliding model, which correlates better to real machine element applications, showed that increasing hardness and yield stress decreases friction. During steady-state friction, an increase in pv regime often changed the sign of the linear relationship between the material property and the friction, which agrees with the frictional theory of polymer/steel sliding pairs.

  16. Teaching Software Engineering Subjects Using a Practical Oriented Approach at the University of Mumbai

    Directory of Open Access Journals (Sweden)

    Mayur S Gondhalekar

    2013-12-01

    Full Text Available The University of Mumbai is one of the oldest and renowned universities in India, catering to nearly 20,000 students in the Computer Engineering and Information Technology Engineering disciplines. This translates to approximately 12,000 qraduates entering the software industry. The structure of the coursework related to Software Engineering subjects - Software Engineering, Software Testing and Quality Assurance, Sofware Project Management and Software Architectures - relies heavily on theoretical classroom teaching. In this paper, we suggest changes to the structure of the coursework by shifting the focus to a project-oriented system, that will give the students a real-world-like experience of the Software Engineering subjects. Graduates with a higher level of practical experience of Software Engineering subjects is a win-win situation for everyone concerned, the software industry, the research institutes, and the students themselves.

  17. Information Flow Through Stages of Complex Engineering Design Projects: A Dynamic Network Analysis Approach

    DEFF Research Database (Denmark)

    Parraguez, Pedro; Eppinger, Steven D.; Maier, Anja

    2015-01-01

    information flows between activities in complex engineering design projects; 2) we show how the network of information flows in a large-scale engineering project evolved over time and how network analysis yields several managerial insights; and 3) we provide a useful new representation of the engineering...... design process and thus support theory-building toward the evolution of information flows through systems engineering stages. Implications include guidance on how to analyze and predict information flows as well as better planning of information flows in engineering design projects according......The pattern of information flow through the network of interdependent design activities is thought to be an important determinant of engineering design process results. A previously unexplored aspect of such patterns relates to the temporal dynamics of information transfer between activities...

  18. Uncovering the Layers of Design Processes of a Global Undergraduate Engineering Course: An Interactional Ethnographic Approach

    Science.gov (United States)

    Joo, Jenna (Ji Eun)

    This dissertation presents an ethnographic study of an instructor's design logic and thinking underlying a global, multi-country undergraduate engineering design course. The study analyzed how, in what ways, and for what purposes, he continually defined and reformulated what counted as (Heap, 1991) "new" learning opportunities and outcomes for engineering design thinking in the 21st century, through his interactions with globally distributed groups of students and teaching teams (i.e., US, India, Israel, China and South Korea). By examining what was discursively made present to students in moment-by-moment and over-time, I identified the processes and practices that members of the class needed to know, understand, produce and engage in (Heath & Street, 2008) to develop their capacities to work in intercultural contexts on local design problems. Discourse analysis guided by an Interactional Ethnographic logic-in-use (Birdwhistell, 1977), grounded in a social construction of knowledge perspective (i.e., Green, Skukauskaite, and Baker, 2012; Castanheira, Crawford, Dixon and Green, 2001), framed the ways in which I examined the work of participants, what they oriented to and were held accountable for, and how what counted as this "new" instructional approach was socially constructed (Heap, 1991; Bloome & Egan-Robertson, 1993, Castanheira et al, 2001). This inquiry process required consideration of multimodal texts available to students in different technology-enabled educational contexts, public (re)presentations of this developing program as well as the construction of transcripts. From this perspective, texts were spoken, written and/or published works (Bakhtin, 1986) constructed by key actors (the designer, the support team, a teaching assistant and students). The analyses made visible how the instructor's discourse focused students on taking a problem-oriented approach to resolving challenges in working interculturally on a common task (e.g., the design thinking

  19. Introduction of Sustainability Concepts into Industrial Engineering Education: A Modular Approach

    Science.gov (United States)

    Nazzal, Dima; Zabinski, Joseph; Hugar, Alexander; Reinhart, Debra; Karwowski, Waldemar; Madani, Kaveh

    2015-01-01

    Sustainability in operations, production, and consumption continues to gain relevance for engineers. This trend will accelerate as demand for goods and services grows, straining resources and requiring ingenuity to replace boundless supply in meeting the needs of a more crowded, more prosperous world. Industrial engineers are uniquely positioned…

  20. A Systematic Approach to Teaching Critical Thinking Skills to Electrical and Computer Engineering Undergraduates

    Science.gov (United States)

    Welch, Karla Conn; Hieb, Jeffrey; Graham, James

    2015-01-01

    Coursework that instills patterns of rigorous logical thought has long been a hallmark of the engineering curriculum. However, today's engineering students are expected to exhibit a wider range of thinking capabilities both to satisfy ABET requirements and to prepare the students to become successful practitioners. This paper presents the initial…

  1. Model-Based Control of an Aircraft Engine using an Optimal Tuner Approach

    Science.gov (United States)

    Connolly, Joseph W.; Chicatelli, Amy; Garg, Sanjay

    2012-01-01

    This paper covers the development of a model-based engine control (MBEC) method- ology applied to an aircraft turbofan engine. Here, a linear model extracted from the Commercial Modular Aero-Propulsion System Simulation 40,000 (CMAPSS40k) at a cruise operating point serves as the engine and the on-board model. The on-board model is up- dated using an optimal tuner Kalman Filter (OTKF) estimation routine, which enables the on-board model to self-tune to account for engine performance variations. The focus here is on developing a methodology for MBEC with direct control of estimated parameters of interest such as thrust and stall margins. MBEC provides the ability for a tighter control bound of thrust over the entire life cycle of the engine that is not achievable using traditional control feedback, which uses engine pressure ratio or fan speed. CMAPSS40k is capable of modeling realistic engine performance, allowing for a verification of the MBEC tighter thrust control. In addition, investigations of using the MBEC to provide a surge limit for the controller limit logic are presented that could provide benefits over a simple acceleration schedule that is currently used in engine control architectures.

  2. An Interactive Simulator-Based Pedagogical (ISP) Approach for Teaching Microcontrollers in Engineering Programs

    Science.gov (United States)

    Tang, Shensheng

    2014-01-01

    Microcontrollers is a required course in most Electrical, Computer, and Mechanic Engineering (Technology) programs at U.S. universities. Most engineering courses (e.g., microcontrollers), by nature, introduce abstract concepts, definitions, and models, and use primarily lectures and readings (words, symbols) to transmit information. This…

  3. A Strategic Approach for Supporting the Future of Civil Engineering Education in Europe

    Science.gov (United States)

    Angelides, Demos C.; Loukogeorgaki, Eva

    2005-01-01

    A new strategic vision of the extensively debated European higher education is proposed with focus on civil engineering. Civil engineering education for the future is considered with relevance to potential world-wide trends and anticipated societal requirements and, therefore, required employee qualifications of the construction-related providers…

  4. One Approach to Senior Level Design in Naval Architecture and Marine Engineering. Report 09-92.

    Science.gov (United States)

    Colella, Kurt J.

    The United States Coast Guard Academy has integrated a successful senior-level ship design course sequence into an undergraduate engineering curriculum in order to achieve specifically desired academic and professional outcomes. The Naval Architecture and Marine Engineering (NAME) curriculum discussed is designed to allow for efficient use of…

  5. Fault Detection of Inline Reciprocating Diesel Engine: A Mass and Gas-Torque Approach

    Directory of Open Access Journals (Sweden)

    S. H. Gawande

    2012-01-01

    Full Text Available Early fault detection and diagnosis for medium-speed diesel engines are important to ensure reliable operation throughout the course of their service. This work presents an investigation of the diesel engine combustion-related fault detection capability of crankshaft torsional vibrations. Proposed methodology state the way of early fault detection in the operating six-cylinder diesel engine. The model of six cylinders DI Diesel engine is developed appropriately. As per the earlier work by the same author the torsional vibration amplitudes are used to superimpose the mass and gas torque. Further mass and gas torque analysis is used to detect fault in the operating engine. The DFT of the measured crankshaft’s speed, under steady-state operating conditions at constant load shows significant variation of the amplitude of the lowest major harmonic order. This is valid both for uniform operating and faulty conditions and the lowest harmonic orders may be used to correlate its amplitude to the gas pressure torque and mass torque for a given engine. The amplitudes of the lowest harmonic orders (0.5, 1, and 1.5 of the gas pressure torque and mass torque are used to map the fault. A method capable to detect faulty cylinder of operating Kirloskar diesel engine of SL90 Engine-SL8800TA type is developed, based on the phases of the lowest three harmonic orders.

  6. Towards Long-Life Replacement Joint Prostheses - A Surface Engineering Approach

    Institute of Scientific and Technical Information of China (English)

    Hanshan Dong

    2004-01-01

    How to improve the wear resistance of bearing surfaces, hereby achieving long life of orthopaedic joint prostheses has long been a technical challenge with much fundamental interest and social and economic impacts. Surface engineering has been emerging as one of the most promising technologies to improve the tribological properties of biomedical materials.A current area of research within the Birmingham Surface Engineering Group has been directed at developing novel surface engineering technologies for biomedical materials towards long-life joint prostheses. Following a brief introduction, the author reports their recent progress in the surface engineering of biomedical materials particular for joint prosthesis. The potential of these innovative surface engineering technologies in enhancing the performance of oral and maxillofacial implants and surgical devices is also discussed.

  7. 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.

  8. Towards Long-Life Replacement Joint Prostheses-A Surface Engineering Approach

    Institute of Scientific and Technical Information of China (English)

    HanshanDong

    2004-01-01

    How to improve the wear resistance of bearing surfaces, hereby achieving long life of orthopaedic joint prostheses has long been a technical challenge with much fundamental interest and social and economic impacts. Surface engineering has been emerging as one of the most promising technologies to improve the tribological properties of biomedical materials. A current area of research within the Birmingham Surface Engineering Group has been directed at developing novel surface engineering technologies for biomedical materials towards long-life joint prostheses. Following a brief introduction, the author reports their recent progress in the surface engineering of biomedical materials particular for joint prosthesis. The potential of these innovative surface engineering technologies in enhancing the performance of oral and maxillofacial implants and surgical devices is also discussed.

  9. 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.

  10. 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.

  11. Applied Laplace transforms and z-transforms for scientists and engineers a computational approach using a Mathematica package

    CERN Document Server

    Graf, Urs

    2004-01-01

    The theory of Laplace transformation is an important part of the mathematical background required for engineers, physicists and mathematicians. Laplace transformation methods provide easy and effective techniques for solving many problems arising in various fields of science and engineering, especially for solving differential equations. What the Laplace transformation does in the field of differential equations, the z-transformation achieves for difference equations. The two theories are parallel and have many analogies. Laplace and z­ transformations are also referred to as operational calculus, but this notion is also used in a more restricted sense to denote the operational calculus of Mikusinski. This book does not use the operational calculus of Mikusinski, whose approach is based on abstract algebra and is not readily accessible to engineers and scientists. The symbolic computation capability of Mathematica can now be used in favor of the Laplace and z-transformations. The first version of the Mathema...

  12. A combinatorial histidine scanning library approach to engineer highly pH-dependent protein switches.

    Science.gov (United States)

    Murtaugh, Megan L; Fanning, Sean W; Sharma, Tressa M; Terry, Alexandra M; Horn, James R

    2011-09-01

    There is growing interest in the development of protein switches, which are proteins whose function, such as binding a target molecule, can be modulated through environmental triggers. Efforts to engineer highly pH sensitive protein-protein interactions typically rely on the rational introduction of ionizable groups in the protein interface. Such experiments are typically time intensive and often sacrifice the protein's affinity at the permissive pH. The underlying thermodynamics of proton-linkage dictate that the presence of multiple ionizable groups, which undergo a pK(a) change on protein binding, are necessary to result in highly pH-dependent binding. To test this hypothesis, a novel combinatorial histidine library was developed where every possible combination of histidine and wild-type residue is sampled throughout the interface of a model anti-RNase A single domain VHH antibody. Antibodies were coselected for high-affinity binding and pH-sensitivity using an in vitro, dual-function selection strategy. The resulting antibodies retained near wild-type affinity yet became highly sensitive to small decreases in pH, drastically decreasing their binding affinity, due to the incorporation of multiple histidine groups. Several trends were observed, such as histidine "hot-spots," which will help enhance the development of pH switch proteins as well as increase our understanding of the role of ionizable residues in protein interfaces. Overall, the combinatorial approach is rapid, general, and robust and should be capable of producing highly pH-sensitive protein affinity reagents for a number of different applications. Copyright © 2011 The Protein Society.

  13. An integrated approach for the in vitro dosimetry of engineered nanomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, J.; Teeguarden, Justin G.; Demokritou, P.

    2014-01-01

    Background: There is a great need for screening tools capable of rapidly assessing nanomaterial toxicity. One impediment to the development of reliable in vitro screening methods is the need for accurate measures of cellular dose. We present here a methodology that enables accurate determination of delivered to cell dose metrics. This methodology includes (1) standardization of engineered nanomaterial (ENM) suspension reparation; (2) measurement of ENM characteristics controlling delivery to cells in culture; and (3) calculation of delivered dose as a function of exposure time using the ISDD model. The approach is validated against experimentally measured doses, and simplified analytical expressions for the delivered dose (Relevant In Vitro Dose (RID)f function) are derived for 20 ENMs. These functions can be used by nanotoxicologists to accurately calculate the total mass (RIDM), surface area (RIDSA), or particle number (RIDN) delivered to cells as a function of exposure time. Results: The proposed methodology was used to derive the effective density, agglomerate diameter and RID functions for 17 industrially-relevant metal and metal oxide ENMs, two carbonaceous nanoparticles, and non-agglomerating gold nanospheres, for two well plate configurations (96 and 384 well plates). For agglomerating ENMs, the measured effective density was on average 60% below the material density. We report great variability in delivered dose metrics, with some materials depositing within 24 hours while others require over 100 hours for delivery to cells. A neutron-activated tracer particle system was employed to validate the proposed in vitro dosimetry methodology for a number of ENMs (measured delivered to cell dose within 9% of estimated). Conclusions: Our findings confirm and extend experimental and computational evidence that agglomerate characteristics affect the dose delivered to cells. Therefore measurement of these characteristics is critical for effective use of in vitro

  14. Polarization engineering and approaches for high-performance III-nitride light emitters

    Science.gov (United States)

    Arif, Ronald A.

    Light emitting diodes (LEDs) have been increasingly integrated into mainstream lighting. In all applications requiring single-colored light, LEDs have outperformed filtered incandescent lamps. However, there are two major challenges. First is the issue of cost. High-performance nitride-based white LEDs cost roughly two orders of magnitude more expensive than incandescent lamps. The second challenge is color rendering---quantified by Color Rendering Index (CRI). Today's nitride white light LEDs still rely on the mixing of blue light from blue InGaN LEDs and yellow phosphor, and the CRI is relatively low. The best white LEDs to date have a CRI of 70--80, in comparison to traditional lamps, which generally have a CRI close to 100, and able to represent the true color of an object. An ideal way to improve the CRI is by mixing the luminescence of primary color LEDs. However, in order to make this approach viable, all the LEDs have to be based on a single materials platform. AlInGaN is the only materials system to date with the potential to fulfill this, since the bandgap of this nitride compound (with varying amount of Al, In, and Ga) can be varied from UV to IR range. There is still a lot of room for improvement in the efficiencies of nitride blue and green LEDs, while nitride-based active region emitting in the red wavelength (lambda ˜ 650-nm) regime is not realizable yet. In this dissertation, methods to increase internal quantum efficiency by polarization field engineering have been proposed. Two novel structures based on (1) staggered InGaN QW and (2) type-II InGaN-GaNAs QW have been investigated. Staggered InGaN QWs have shown improvement in the photoluminescence, cathodoluminescence, and LED output power, which agree well with numerical model prediction. All materials and devices in this work have been designed, grown and fabricated in-house. For the LED fabrication, a method based on selective area epitaxy---which bypasses dry-etching---has been utilized. In

  15. Breaking it into pieces for storage: An engineering approach to enhancing supercritical CO2 entrapment

    Science.gov (United States)

    Wang, Y.; Bryan, C. R.; Dewers, T. A.; Heath, J. E.

    2011-12-01

    Geologic carbon sequestration and storage (CSS) is a possible option for the mitigation of carbon dioxide (CO2) emissions to the atmosphere. Residual trapping of a non-wetting liquid phase in a brine reservoir is considered as an important mechanism for long-term CSS, because similar processes have been observed in a variety of fields such as oil recovery and groundwater remediation of non-aqueous phase liquids. Residual trapping can potentially relax stringent requirements for the integrity of cap rocks and allow utilization of open or dipping structures for carbon storage. Here, we propose an engineering approach to enhancing the immobilization of supercritical CO2 (scCO2) in a brine reservoir. This approach is based on the concept of viscous instability of immiscible flow and the dynamics of the movement of scCO2 ganglia in porous media. The movement of a non-wetting ganglion is inversely dependent on its dimension: the smaller the ganglion, the more difficult to move. The critical size (lc) for a ganglion to become immobilized, given its buoyancy, is determined by: lc=2βσ/(rkrw Δρg) where β is the geometric factor characterizing the grain size and pore neck radius (r), σ is the interfacial tension between scCO2 and water, rkrw is the relative permeability to water, Δρ is the density difference between water and scCO2, and g is the gravity. This suggests that, by dispersing injected scCO2 into small ganglia, we can potentially immobilize the injected scCO2 for very long times. The dispersal of scCO2 into small ganglia could be accomplished by controlling the injection rate and the alternating injection of scCO2 and water. The injection rate is required to be high enough to ensure the scCO2 at the advancing front to be broken into pieces, small enough for immobilization, through viscous instability: v>(2π2 r2 krkrw Δρ2 g2)/(μβ2 σ) where v is the velocity of the advancement of scCO2 front, k is the permeability of water and μ is the viscosity of

  16. Rocket Engine Nozzle Side Load Transient Analysis Methodology: A Practical Approach

    Science.gov (United States)

    Shi, John J.

    2005-01-01

    At the sea level, a phenomenon common with all rocket engines, especially for a highly over-expanded nozzle, during ignition and shutdown is that of flow separation as the plume fills and empties the nozzle, Since the flow will be separated randomly. it will generate side loads, i.e. non-axial forces. Since rocket engines are designed to produce axial thrust to power the vehicles, it is not desirable to be excited by non-axial input forcing functions, In the past, several engine failures were attributed to side loads. During the development stage, in order to design/size the rocket engine components and to reduce the risks, the local dynamic environments as well as dynamic interface loads have to be defined. The methodology developed here is the way to determine the peak loads and shock environments for new engine components. In the past it is not feasible to predict the shock environments, e.g. shock response spectra, from one engine to the other, because it is not scaleable. Therefore, the problem has been resolved and the shock environments can be defined in the early stage of new engine development. Additional information is included in the original extended abstract.

  17. Knowledge-driven approaches for engineering complex metabolic pathways in plants.

    Science.gov (United States)

    Farré, Gemma; Twyman, Richard M; Christou, Paul; Capell, Teresa; Zhu, Changfu

    2015-04-01

    Plant metabolic pathways are complex and often feature multiple levels of regulation. Until recently, metabolic engineering in plants relied on the laborious testing of ad hoc modifications to achieve desirable changes in the metabolic profile. However, technological advances in data mining, modeling, multigene engineering and genome editing are now taking away much of the guesswork by allowing the impact of modifications to be predicted more accurately. In this review we discuss recent developments in knowledge-based metabolic engineering strategies, that is the gathering and mining of genomic, transcriptomic, proteomic and metabolomic data to generate models of metabolic pathways that help to define and refine optimal intervention strategies.

  18. A transient tribodynamic approach for the calculation of internal combustion engine piston slap noise

    Science.gov (United States)

    Dolatabadi, N.; Littlefair, B.; De la Cruz, M.; Theodossiades, S.; Rothberg, S. J.; Rahnejat, H.

    2015-09-01

    An analytical/numerical methodology is presented to calculate the radiated noise due to internal combustion engine piston impacts on the cylinder liner through a film of lubricant. Both quasi-static and transient dynamic analyses coupled with impact elasto-hydrodynamics are reported. The local impact impedance is calculated, as well as the transferred energy onto the cylinder liner. The simulations are verified against experimental results for different engine operating conditions and for noise levels calculated in the vicinity of the engine block. Continuous wavelet signal processing is performed to identify the occurrence of piston slap noise events and their spectral content, showing good conformance between the predictions and experimentally acquired signals.

  19. Multimedia Environmental Fate and Speciation of Engineered Nanoparticles: A Probabilistic Modeling Approach

    NARCIS (Netherlands)

    Meesters, J.; Quik, J.T.K.; Koelmans, A.A.; Hendriks, A.J.; Meent, van de D.

    2016-01-01

    The robustness of novel multimedia fate models in environmental exposure estimation of engineered nanoparticles (ENPs) remains unclear, because of uncertainties in the emission, physicochemical properties and natural variability in environmental systems. Here, we evaluate the uncertainty in predicte

  20. Tissue engineering approaches for the construction of a completely autologous tendon substitute

    Directory of Open Access Journals (Sweden)

    Bassetto Franco

    2008-01-01

    Full Text Available Tissue engineering is a multidisciplinary field that involves the application of the principles and methods of engineering and life sciences towards i the fundamental understanding of structure-function relationships in normal and pathological mammalian tissues and ii the development of biological substitutes that restore, maintain or improve tissue function. The goal of tissue engineering is to surpass the limitations of conventional treatments based on organ transplantation and biomaterial implantation. The field of tendon tissue engineering is relatively unexplored due to the difficulty in in vitro preservation of tenocyte phenotype. Only recently has mechanobiology allowed us to gain a better understanding of the fundamental role of in vitro mechanical stimuli in maintaining the phenotype of tendinous tissue. This review analyzes the techniques used so far for in vitro regeneration of tendinous tissue.

  1. Post engineered nanomaterials lifespan: nanowastes classification, legislative development/implementation challenges, and proactive approaches

    CSIR Research Space (South Africa)

    Musee, N

    2012-05-01

    Full Text Available -1 NANOLCA Symposium, "Safety issues and regulatory challenges of nanomaterials", San Sebastian, Spain, 3-4 May 2012 Post engineered nanomaterials lifespan: nanowastes classification, legislative development/implementation challenges, and proactive...

  2. Multimedia Environmental Fate and Speciation of Engineered Nanoparticles: A Probabilistic Modeling Approach

    NARCIS (Netherlands)

    Meesters, J.; Quik, J.T.K.; Koelmans, A.A.; Hendriks, A.J.; Meent, van de D.

    2016-01-01

    The robustness of novel multimedia fate models in environmental exposure estimation of engineered nanoparticles (ENPs) remains unclear, because of uncertainties in the emission, physicochemical properties and natural variability in environmental systems. Here, we evaluate the uncertainty in

  3. AN EFFICIENT APPROACH FOR KEYWORD SELECTION; IMPROVING ACCESSIBILITY OF WEB CONTENTS BY GENERAL SEARCH ENGINES

    Directory of Open Access Journals (Sweden)

    H. H. Kian

    2011-11-01

    Full Text Available General search engines often provide low precise results even for detailed queries. So there is a vital needto elicit useful information like keywords for search engines to provide acceptable results for user’s searchqueries. Although many methods have been proposed to show how to extract keywords automatically, allattempt to get a better recall, precision and other criteria which describe how the method has done its jobas an author. This paper presents a new automatic keyword extraction method which improves accessibilityof web content by search engines. The proposed method defines some coefficients determining featuresefficiency and tries to optimize them by using a genetic algorithm. Furthermore, it evaluates candidatekeywords by a function that utilizes the result of search engines. When comparing to the other methods,experiments demonstrate that by using the proposed method, a higher score is achieved from searchengines without losing noticeable recall or precision.

  4. An Engineering Approach to Management of Occupational and Community Noise Exposure at NASA Lewis Research Center

    Science.gov (United States)

    Cooper, Beth A.

    1997-01-01

    Workplace and environmental noise issues at NASA Lewis Research Center are effectively managed via a three-part program that addresses hearing conservation, community noise control, and noise control engineering. The Lewis Research Center Noise Exposure Management Program seeks to limit employee noise exposure and maintain community acceptance for critical research while actively pursuing engineered controls for noise generated by more than 100 separate research facilities and the associated services required for their operation.

  5. Review of the Space Mapping Approach to Engineering Optimization and Modeling

    DEFF Research Database (Denmark)

    Bakr, M. H.; Bandler, J. W.; Madsen, Kaj

    2000-01-01

    We review the Space Mapping (SM) concept and its applications in engineering optimization and modeling. The aim of SM is to avoid computationally expensive calculations encountered in simulating an engineering system. The existence of less accurate but fast physically-based models is exploited. S......-based Modeling (SMM). These include Space Derivative Mapping (SDM), Generalized Space Mapping (GSM) and Space Mapping-based Neuromodeling (SMN). Finally, we address open points for research and future development....

  6. Development of Systems Engineering Competency Career Development Model: An Analytical Approach using Blooms Taxonomy

    Science.gov (United States)

    2014-06-01

    highlight application. LIST OF REFERENCES Whitcomb, Clifford, Rabia Khan, and Corina White. 2013. “Systems Engineering Competency Report” Paper...thank my colleagues Rabia Khan, Juli Alexander, Paul Castanzo, and Paul Walter. As a result of Dr. Whitcomb’s vision, each of our projects fits...Master’s thesis, Naval Postgraduate School. Whitcomb, Clifford, Rabia Khan, and Corina White. 2013. “Systems Engineering Competency Report.” Paper

  7. Seeding cell approach for tissue-engineered urethral reconstruction in animal study: A systematic review and meta-analysis.

    Science.gov (United States)

    Xue, Jing-Dong; Gao, Jing; Fu, Qiang; Feng, Chao; Xie, Hong

    2016-07-01

    We systematically reviewed published preclinical studies to evaluate the effectiveness of cell-seeded tissue engineering approach for urethral reconstruction in an animal model. The outcomes were summarized by success factors in the animal experiments, which evaluate the possibility and feasibility of a clinical application in the future. Preclinical studies of tissue engineering approaches for urethral reconstruction were identified through a systematic search in PubMed, Embase, and Biosis Previews (web of science SP) databases for studies published from 1 January 1980 to 23 November 2014. Primary studies were included if urethral reconstruction was performed using a tissue-engineered biomaterial in any animal species (with the experiment group being a cell-seeded scaffold and the control group being a cell-free scaffold) with histology and urethrography as the outcome measure. A total of 15 preclinical studies were included in our meta-analysis. The histology and urethrography outcome between the experimental and control groups were considered to be the most clinically relevant. Through this systematic approach, our outcomes suggested that applying the cell-seeded biomaterial in creating a neo-urethra was stable and effective. And multi-type cells including epithelial cells as well as smooth muscle cells or fibroblasts seemed to be a better strategy. Stem cells, especially after epithelial differentiation, could be a promising choice for future researches. © 2016 by the Society for Experimental Biology and Medicine.

  8. A fault diagnosis approach for diesel engine valve train based on improved ITD and SDAG-RVM

    Science.gov (United States)

    Yu, Liu; Junhong, Zhang; Fengrong, Bi; Jiewei, Lin; Wenpeng, Ma

    2015-02-01

    Targeting the non-stationary characteristics of the vibration signals of a diesel engine valve train, and the limitation of the autoregressive (AR) model, a novel approach based on the improved intrinsic time-scale decomposition (ITD) and relevance vector machine (RVM) is proposed in this paper for the identification of diesel engine valve train faults. The approach mainly consists of three stages: First, prior to the feature extraction, non-uniform B-spline interpolation is introduced to the ITD method for the fitting of baseline signal, then the improved ITD is used to decompose the non-stationary signals into a set of stationary proper rotation components (PRCs). Second, the AR model is established for each PRC, and the first several AR coefficients together with the remnant variance of all PRCs are regarded as the fault feature vectors. Finally, a new separability based directed acyclic graph (SDAG) method is proposed to determine the structure of multi-class RVM, and the fault feature vectors are classified using the SDAG-RVM classifier to recognize the fault of the diesel engine valve train. The experimental results demonstrate that the proposed fault diagnosis approach can effectively extract the fault features and accurately identify the fault patterns.

  9. Enhancing vehicle’s engine warm up using integrated mechanical approach

    Science.gov (United States)

    Ibrahim, T. M.; Syahir, A. Z.; Zulkifli, N. W. M.; Masjuki, H. H.; Osman, A.

    2017-06-01

    Transportation sector covers a large portion of the total energy consumption shares and is highly associated to global warming. Growing concern over the harmful gases being emitted from vehicles and their environmental implications has urged the need for pollutant reduction through more efficient engines. Good engine thermal management especially during cold-start warm up phase has been proven to enhance the engine efficiency in terms of fuel economy and greenhouse emissions specifically. In this study, the viability engine split cooling system was tested in two separate test. The parameters of interest include coolant and transmission temperature as these both parameters indicate the internal engine condition and highly associated with engine efficiency. In the first idle test, coolant temperature within the modified cooling configuration reached the optimum coolant temperature of 60 °C about 41.28% faster when compared to baseline configuration. The modified configuration also heat up the transmission oil around 4 times faster. In the second NEDC test which simulates the real time driving condition, the coolant of the modified vehicle reached the optimum temperature around 28.26% compared to the baseline.

  10. 3D integrated modeling approach to geo-engineering objects of hydraulic and hydroelectric projects

    Institute of Scientific and Technical Information of China (English)

    ZHONG DengHua; LI MingChao; LIU Jie

    2007-01-01

    Aiming at 3D modeling and analyzing problems of hydraulic and hydroelectric engineering geology, a complete scheme of solution is presented. The first basis was NURBS-TIN-BRep hybrid data structure. Then, according to the classified thought of the object-oriented technique, the different 3D models of geological and engineering objects were realized based on the data structure, including terrain class,strata class, fault class, and limit class; and the modeling mechanism was alternative. Finally, the 3D integrated model was established by Boolean operations between 3D geological objects and engineering objects. On the basis of the 3D model,a series of applied analysis techniques of hydraulic and hydroelectric engineering geology were illustrated. They include the visual modeling of rock-mass quality classification, the arbitrary slicing analysis of the 3D model, the geological analysis of the dam, and underground engineering. They provide powerful theoretical principles and technical measures for analyzing the geological problems encountered in hydraulic and hydroelectric engineering under complex geological conditions.

  11. 3D integrated modeling approach to geo-engineering objects of hydraulic and hydroelectric projects

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Aiming at 3D modeling and analyzing problems of hydraulic and hydroelectric en-gineering geology,a complete scheme of solution is presented. The first basis was NURBS-TIN-BRep hybrid data structure. Then,according to the classified thought of the object-oriented technique,the different 3D models of geological and engi-neering objects were realized based on the data structure,including terrain class,strata class,fault class,and limit class;and the modeling mechanism was alterna-tive. Finally,the 3D integrated model was established by Boolean operations be-tween 3D geological objects and engineering objects. On the basis of the 3D model,a series of applied analysis techniques of hydraulic and hydroelectric engineering geology were illustrated. They include the visual modeling of rock-mass quality classification,the arbitrary slicing analysis of the 3D model,the geological analysis of the dam,and underground engineering. They provide powerful theoretical prin-ciples and technical measures for analyzing the geological problems encountered in hydraulic and hydroelectric engineering under complex geological conditions.

  12. MSblender: A probabilistic approach for integrating peptide identifications from multiple database search engines.

    Science.gov (United States)

    Kwon, Taejoon; Choi, Hyungwon; Vogel, Christine; Nesvizhskii, Alexey I; Marcotte, Edward M

    2011-07-01

    Shotgun proteomics using mass spectrometry is a powerful method for protein identification but suffers limited sensitivity in complex samples. Integrating peptide identifications from multiple database search engines is a promising strategy to increase the number of peptide identifications and reduce the volume of unassigned tandem mass spectra. Existing methods pool statistical significance scores such as p-values or posterior probabilities of peptide-spectrum matches (PSMs) from multiple search engines after high scoring peptides have been assigned to spectra, but these methods lack reliable control of identification error rates as data are integrated from different search engines. We developed a statistically coherent method for integrative analysis, termed MSblender. MSblender converts raw search scores from search engines into a probability score for every possible PSM and properly accounts for the correlation between search scores. The method reliably estimates false discovery rates and identifies more PSMs than any single search engine at the same false discovery rate. Increased identifications increment spectral counts for most proteins and allow quantification of proteins that would not have been quantified by individual search engines. We also demonstrate that enhanced quantification contributes to improve sensitivity in differential expression analyses.

  13. Engineered Biosynthesis of Plant Polyketides: Structure-Based and Precursor-Directed Approach

    Science.gov (United States)

    Abe, Ikuro

    benzoyl-CoA as a starter substrate. These results suggested that the engineered biosynthesis of plant polyketides by combination of the structure-based and the precursor-directed approach would lead to further production of chemically and structurally divergent unnatural novel polyketides.

  14. Chemical and engineering approaches to enable organic field-effect transistors for electronic skin applications.

    Science.gov (United States)

    Sokolov, Anatoliy N; Tee, Benjamin C-K; Bettinger, Christopher J; Tok, Jeffrey B-H; Bao, Zhenan

    2012-03-20

    Skin is the body's largest organ and is responsible for the transduction of a vast amount of information. This conformable material simultaneously collects signals from external stimuli that translate into information such as pressure, pain, and temperature. The development of an electronic material, inspired by the complexity of this organ is a tremendous, unrealized engineering challenge. However, the advent of carbon-based electronics may offer a potential solution to this long-standing problem. In this Account, we describe the use of an organic field-effect transistor (OFET) architecture to transduce mechanical and chemical stimuli into electrical signals. In developing this mimic of human skin, we thought of the sensory elements of the OFET as analogous to the various layers and constituents of skin. In this fashion, each layer of the OFET can be optimized to carry out a specific recognition function. The separation of multimodal sensing among the components of the OFET may be considered a "divide and conquer" approach, where the electronic skin (e-skin) can take advantage of the optimized chemistry and materials properties of each layer. This design of a novel microstructured gate dielectric has led to unprecedented sensitivity for tactile pressure events. Typically, pressure-sensitive components within electronic configurations have suffered from a lack of sensitivity or long mechanical relaxation times often associated with elastomeric materials. Within our method, these components are directly compatible with OFETs and have achieved the highest reported sensitivity to date. Moreover, the tactile sensors operate on a time scale comparable with human skin, making them ideal candidates for integration as synthetic skin devices. The methodology is compatible with large-scale fabrication and employs simple, commercially available elastomers. The design of materials within the semiconductor layer has led to the incorporation of selectivity and sensitivity within

  15. A tissue engineering approach to anterior cruciate ligament regeneration using novel shaped capillary channel polymer fibers

    Science.gov (United States)

    Sinclair, Kristofer D.

    2009-12-01

    Ruptures of the anterior cruciate ligament (ACL) are the most frequent of injuries to the knee due to its role in preventing anterior translation of the tibia. It is estimated that as many as 200,000 Americans per year will suffer from a ruptured ACL, resulting in management costs on the order of 5 billion dollars. Without treatment these patients are unable to return to normal activity, as a consequence of the joint instability found within the ACL deficient knee. Over the last thirty years, a variety of non-degradable, synthetic fibers have been evaluated for their use in ACL reconstruction; however, a widely accepted prosthesis has been unattainable due to differences in mechanical properties of the synthetic graft relative to the native tissue. Tissue engineering is an interdisciplinary field charged with the task of developing therapeutic solutions for tissue and organ failure by enhancing the natural wound healing process through the use of cellular transplants, biomaterials, and the delivery of bioactive molecules. The capillary channel polymer (CC-P) fibers used in this research were fabricated by melt extrusion from polyethylene terephthalate and polybutylene terephthalate. These fibers possess aligned micrometer scale surface channels that may serve as physical templates for tissue growth and regeneration. This inherent surface topography offers a unique and industrially viable approach for cellular contact guidance on three dimensional constructs. In this fundamental research the ability of these fiber channels to support the adhesion, alignment, and organization of fibroblasts was demonstrated and found to be superior to round fiber controls. The results demonstrated greater uniformity of seeding and accelerated formation of multi-layered three-dimensional biomass for the CC-P fibers relative to those with a circular cross-section. Furthermore, the CC-P geometry induced nuclear elongation consistent with that observed in native ACL tissue. Through the

  16. THE INTEGRATION OF ENGINEERED AND INSTITUTIONAL CONTROLS: A CASE STUDY APPROACH WITH LESSONS LEARNED FROM PREVIOUSLY CLOSED SITES

    Energy Technology Data Exchange (ETDEWEB)

    Kevin M. Kostelnik; James H. Clarke; Jerry L. Harbour

    2005-02-01

    Environmental remediation efforts that are underway at hundreds of contaminated sites in the United States will not be able to remediate large portions of those sites to conditions that would permit unrestricted access. Rather, large volumes of waste materials, contaminated soils and cleanup residuals will have to be isolated either in place or in new, often on-site, disposal cells with long term monitoring, maintenance and institutional control needs. The challenge continues to be to provide engineering systems and controls that can ensure the protection of public health and the environment over very long time horizons (hundreds to perhaps thousands of years) with minimal intervention. Effective long term management of legacy hazardous and nuclear waste requires an integrated approach that addresses both the engineered containment and control system itself and the institutional controls and other responsibilities that are needed. Decisions concerning system design, monitoring and maintenance, and the institutional controls that will be employed are best done through a "risk-nformed, performance-based" approach. Such an approach should incorporate an analysis of potential "failure" modes and consequences for all important system features, together with lessons learned from experience with systems already in place. The authors will present the preliminary results of a case study approach that included several sites where contamination isolation systems including institutional controls have been implemented. The results are being used together with failure trees and logic diagrams that have been developed for both the engineered barriers and the institutional controls. The use of these analytical tools to evaluate the potential for different levels of failure and associated consequences will be discussed. Of special interest is the robustness of different approaches to providing long-term protection through redundancy and defense in depth.

  17. Validation of engineering dynamic inflow models by experimental and numerical approaches

    Science.gov (United States)

    Yu, W.; Hong, V. W.; Ferreira, C.; van Kuik, G. A. M.

    2016-09-01

    The state of the art engineering dynamic inflow models of Pitt-Peters, Øye and ECN have been used to correct Blade Element Momentum theory for unsteady load prediction of a wind turbine for two decades. However, their accuracy is unknown. This paper is to benchmark the performance of these engineering models by experimental and numerical methods. The experimental load and flow measurements of an unsteady actuator disc were performed in the Open Jet Facility at Delft University of Technology. The unsteady load was generated by a ramp-type variation of porosity of the disc. A Reynolds Averaged Navier-Stokes (RANS) model, a Free Wake Vortex Ring (FWVR) model and a Vortex Tube Model (VTM) simulate the same transient load changes. The velocity field obtained from the experimental and numerical methods are compared with the engineering dynamic inflow models. Velocity comparison aft the disc between the experimental and numerical methods shows the numerical models of RANS and FWVR model are capable to predict the velocity transient behaviour during transient disc loading. Velocity comparison at the disc between the engineering models and the numerical methods further shows that the engineering models predict much faster velocity decay, which implies the need for more advanced or better tuned dynamic inflow models.

  18. Genetic engineering of novel flower colors in floricultural plants: recent advances via transgenic approaches.

    Science.gov (United States)

    Nishihara, Masahiro; Nakatsuka, Takashi

    2010-01-01

    Since the first successful genetic engineering of flower color in petunia, several new techniques have been developed and applied to modify flower color not only in model plants but also in floricultural plants. A typical example is the commercial violet-flowered carnation "Moondust series" developed by Suntry Ltd. and Florigene Ltd. More recently, blue-flowered roses have been successfully produced and are expected to be commercially available in the near future. In recent years, successful modification of flower color by sophisticated regulation of flower-pigment metabolic pathways has become possible. In this chapter, we review recent advances in flower color modification by genetic engineering, especially focusing on the methodology. We have included our own recent results on successful production of flower-color-modified transgenic plants in a model plant, tobacco and an ornamental plant, gentian. Based on these results, genetic engineering of flower color for improvement of floricultural plants is discussed.

  19. Metabolic engineering and synthetic biology approaches driving isoprenoid production in Escherichia coli.

    Science.gov (United States)

    Wang, Chonglong; Zada, Bakht; Wei, Gongyuan; Kim, Seon-Won

    2017-10-01

    Isoprenoids comprise the largest family of natural organic compounds with many useful applications in the pharmaceutical, nutraceutical, and industrial fields. Rapid developments in metabolic engineering and synthetic biology have facilitated the engineering of isoprenoid biosynthetic pathways in Escherichia coli to induce high levels of production of many different isoprenoids. In this review, the stem pathways for synthesizing isoprene units as well as the branch pathways deriving diverse isoprenoids from the isoprene units have been summarized. The review also highlights the metabolic engineering efforts made for the biosynthesis of hemiterpenoids, monoterpenoids, sesquiterpenoids, diterpenoids, carotenoids, retinoids, and coenzyme Q10 in E. coli. Perspectives and future directions for the synthesis of novel isoprenoids, decoration of isoprenoids using cytochrome P450 enzymes, and secretion or storage of isoprenoids in E. coli have also been included. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Biotechnology and synthetic biology approaches for metabolic engineering of bioenergy crops.

    Science.gov (United States)

    Shih, Patrick M; Liang, Yan; Loqué, Dominique

    2016-07-01

    The Green Revolution has fuelled an exponential growth in human population since the mid-20th century. Due to population growth, food and energy demands will soon surpass supply capabilities. To overcome these impending problems, significant improvements in genetic engineering will be needed to complement breeding efforts in order to accelerate the improvement of agronomical traits. The new field of plant synthetic biology has emerged in recent years and is expected to support rapid, precise, and robust engineering of plants. In this review, we present recent advances made in the field of plant synthetic biology, specifically in genome editing, transgene expression regulation, and bioenergy crop engineering, with a focus on traits related to lignocellulose, oil, and soluble sugars. Ultimately, progress and innovation in these fields may facilitate the development of beneficial traits in crop plants to meet society's bioenergy needs.

  1. Applying Rock Engineering Systems (RES approach to Evaluate and Classify the Coal Spontaneous Combustion Potential in Eastern Alborz Coal Mines

    Directory of Open Access Journals (Sweden)

    Amir Saffari

    2013-12-01

    Full Text Available Subject analysis of the potential of spontaneous combustion in coal layers with analytical and numerical methods has been always considered as a difficult task because of the complexity of the coal behavior and the number of factors influencing it. Empirical methods, due to accounting for certain and specific factors, have not accuracy and efficiency for all positions. The Rock Engineering Systems (RES approach as a systematic method for analyzing and classifying is proposed in engineering projects. The present study is concerned with employing the RES approach to categorize coal spontaneous combustion in coal regions. Using this approach, the interaction of parameters affecting each other in an equal scale on the coal spontaneous combustion was evaluated. The Intrinsic, geological and mining characteristics of coal seams were studied in order to identifying important parameters. Then, the main stages of implementation of the RES method i.e. interaction matrix formation, coding matrix and forming a list category were performed. Later, an index of Coal Spontaneous Combustion Potential (CSCPi was determined to format the mathematical equation. Then, the obtained data related to the intrinsic, geological and mining, and special index were calculated for each layer in the case study (Pashkalat coal region, Iran. So, the study offers a perfect and comprehensive classification of the layers. Finally, by using the event of spontaneous combustion occurred in Pashkalat coal region, an initial validation for this systematic approach in the study area was conducted, which suggested relatively good concordance in Pashkalat coal region.

  2. An Approach to Enhance the Efficiency of a Brownian Heat Engine

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yan-Ping; HE Ji-Zhou; XIAO Yu-Ling

    2011-01-01

    A Brownian microscopic heat engine, driven by temperature difference and consisting of a Brownian particle moving in a sawtooth potential with an external load, is investigated. The heat Hows, driven by both potential and kinetic energies, are taken into account. Based on the master equation, the expressions for efficiency and power output are derived analytically, and performance characteristic curves are plotted. It is shown that the heat How via the kinetic energy of the particle decreases. The efficiency of the engine is enhanced, but the power output reduces as the a shape parameter of the sawtooth potential increases. The influence of the a shape parameter on efficiency and power output is then analyzed in detail.%A Brownian microscopic heat engine,driven by temperature difference and consisting of a Brownian particle moving in a sawtooth potential with an external load,is investigated.The heat flows,driven by both potential and kinetic energies,are taken into account.Based on the master equation,the expressions for efficiency and power output are derived analytically,and performance characteristic curves are plotted.It is shown that the heat flow via the kinetic energy of the particle decreases.The efficiency of the engine is enhanced,but the power output reduces as the α shape parameter of the sawtooth potential increases.The influence of the α shape parameter on efficiency and power output is then analyzed in detail.Like the Carnot cycle,the Brownian heat engine can extract work from the temperature difference between heat reservoirs,where the Brownian working material operates as a transducer of thermal energy into mechanical work.In the last few decades,the study of Brownian heat engines has received considerable attention,not only for the construction of the miniaturized engine that helps us utilize energy resources at microscopic scales,but also for a better understanding of nonequilibrium statistical physics.[1-3] The thermodynamic properties of the

  3. An Approach to Checking 3D Model with Related Engineering Drawings

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    For some reasons, engineers build their product 3D mo del according to a set of related engineering drawings. The problem is how we ca n know the 3D model is correct. The manual checking is very boring and time cons uming, and still could not avoid mistakes. Thus, we could not confirm the model, maybe try checking again. It will effect the production preparing cycle greatly , and should be solved in a intelligent way. The difficulties are quite obvious, unlike word checking in a word processing package, ...

  4. BUSINESS MANAGEMENT THEORY DEVELOPED ON THE BASIS OF SYSTEM APPROACH AND BUSINESS ENGINEERING TOOLS

    Directory of Open Access Journals (Sweden)

    N. I. Strich

    2011-01-01

    Full Text Available Management should be carried out with due account of the system theory and using tools and opportunities offered by such modern management components as business engineering and reengineering. Main points of this theory are given along with detailed determination of business engineering and reengineering particularly efficient while determining measures needed to reorganize an enterprise (or a group of enterprises through updating its organizational structure as well as economic, personnel or other system. Out-sourcing also described in detail is considered as modern enterprise management system’s most efficient instrument.

  5. Gasoline compression ignition approach to efficient, clean and affordable future engines

    KAUST Repository

    Kalghatgi, Gautam

    2017-04-03

    The worldwide demand for transport fuels will increase significantly but will still be met substantially (a share of around 90%) from petroleum-based fuels. This increase in demand will be significantly skewed towards commercial vehicles and hence towards diesel and jet fuels, leading to a probable surplus of lighter low-octane fuels. Current diesel engines are efficient but expensive and complicated because they try to reduce the nitrogen oxide and soot emissions simultaneously while using conventional diesel fuels which ignite very easily. Gasoline compression ignition engines can be run on gasoline-like fuels with a long ignition delay to make low-nitrogen-oxide low-soot combustion very much easier. Moreover, the research octane number of the optimum fuel for gasoline compression ignition engines is likely to be around 70 and hence the surplus low-octane components could be used without much further processing. Also, the final boiling point can be higher than those of current gasolines. The potential advantages of gasoline compression ignition engines are as follows. First, the engine is at least as efficient and clean as current diesel engines but is less complicated and hence could be cheaper (lower injection pressure and after-treatment focus on control of carbon monoxide and hydrocarbon emissions rather than on soot and nitrogen oxide emissions). Second, the optimum fuel requires less processing and hence would be easier to make in comparison with current gasoline or diesel fuel and will have a lower greenhouse-gas footprint. Third, it provides a path to mitigate the global demand imbalance between heavier fuels and lighter fuels that is otherwise projected and improve the sustainability of refineries. The concept has been well demonstrated in research engines but development work is needed to make it feasible on practical vehicles, e.g. on cold start, adequate control of exhaust carbon monoxide and hydrocarbons and control of noise at medium to high loads

  6. 3D game engine design a practical approach to real-time computer graphics

    CERN Document Server

    Eberly, David H

    2006-01-01

    A major revision of the international bestseller on game programming!Graphics hardware has evolved enormously in the last decade. Hardware can now be directly controlled through techniques such as shader programming, which requires an entirely new thought process of a programmer. 3D Game Engine Design, Second Edition shows step-by-step how to make a shader-based graphics engine and how to tame the new technology. Much new material has been added, including more than twice the coverage of the essential techniques of scene graph management, as well as new methods for manag

  7. A contemporary view of systems engineering. [definition of system and discussion of systems approach

    Science.gov (United States)

    Miles, R. F., Jr.

    1974-01-01

    The concept of a 'system' is defined, and the 'systems approach' is discussed. Four contemporary examples of the systems approach are presented: an operations research project, the planning-programming-budgeting system, an information processing system, and aerospace programs.

  8. Prognostic and health management for engineering systems: a review of the data-driven approach and algorithms

    Directory of Open Access Journals (Sweden)

    Thamo Sutharssan

    2015-07-01

    Full Text Available Prognostics and health management (PHM has become an important component of many engineering systems and products, where algorithms are used to detect anomalies, diagnose faults and predict remaining useful lifetime (RUL. PHM can provide many advantages to users and maintainers. Although primary goals are to ensure the safety, provide state of the health and estimate RUL of the components and systems, there are also financial benefits such as operational and maintenance cost reductions and extended lifetime. This study aims at reviewing the current status of algorithms and methods used to underpin different existing PHM approaches. The focus is on providing a structured and comprehensive classification of the existing state-of-the-art PHM approaches, data-driven approaches and algorithms.

  9. Successful K-12 STEM Education: Identifying Effective Approaches in Science, Technology, Engineering, and Mathematics

    Science.gov (United States)

    National Academies Press, 2011

    2011-01-01

    Science, technology, engineering, and mathematics (STEM) are cultural achievements that reflect our humanity, power our economy, and constitute fundamental aspects of our lives as citizens, consumers, parents, and members of the workforce. Providing all students with access to quality education in the STEM disciplines is important to our nation's…

  10. Application of the Total Quality Management Approach Principles and the ISO 9000 Standards in Engineering Education.

    Science.gov (United States)

    Waks, Shlomo; Frank, Moti

    1999-01-01

    Discusses the applicability of the definition, principles, and underlying strategies of total quality management (TQM) for engineering education. Describes several tools and methods for the implementation of TQM and its suitability for a variety of school activities. Presents a TQM course outline combining lectures, discussions, suggested…

  11. Trends and approaches in N-Glycosylation engineering in Chinese hamster ovary cell culture

    DEFF Research Database (Denmark)

    Fan, Yuzhou; Kildegaard, Helene Faustrup; Andersen, Mikael Rørdam

    , in particular, of those as drug substances, is extremely concerned in drug development andapproval, as it will largely affect their stability, efficacy, clearance rate and immunogenicity. Therefore to engineering N-glycosylationof CHO cell-derived recombinant proteins are extremely important. Here, we...

  12. Diversifying Science, Technology, Engineering, and Mathematics (STEM): An Inquiry into Successful Approaches in Chemistry

    Science.gov (United States)

    Wilson, Zakiya S.; McGuire, Saundra Y.; Limbach, Patrick A.; Doyle, Michael P.; Marzilli, Luigi G.; Warner, Isiah M.

    2014-01-01

    For many years, the U.S. has underutilized its human resources, as evidenced by the pervasive underrepresentation of several racial and ethnic groups within academia in general and the science, technology, engineering, and mathematics (STEM) disciplines, in particular. To address this underutilization, academic departments within U.S. universities…

  13. Establishing the Overall Service Quality of Engineering Education: Fuzzy Logic Approach

    Science.gov (United States)

    Shekhar, N. Chandra; Venkatasubbaiah, K.; Kandukuria, N. R.

    2012-01-01

    Measuring overall service quality (OSQ) is gaining prominence in higher education due to the increased competition among engineering education institutions (EEIs) and growing awareness about value for money among the public. Determination of OSQ on certain institutional aspects is done by various agencies throughout the world. Each system uses a…

  14. The Chemical Engineer's Toolbox: A Glass Box Approach to Numerical Problem Solving

    Science.gov (United States)

    Coronell, Daniel G.; Hariri, M. Hossein

    2009-01-01

    Computer programming in undergraduate engineering education all too often begins and ends with the freshman programming course. Improvements in computer technology and curriculum revision have improved this situation, but often at the expense of the students' learning due to the use of commercial "black box" software. This paper describes the…

  15. Thrust Performance Evaluation of a Turbofan Engine Based on Exergetic Approach and Thrust Management in Aircraft

    Science.gov (United States)

    Yalcin, Enver

    2017-05-01

    The environmental parameters such as temperature and air pressure which are changing depending on altitudes are effective on thrust and fuel consumption of aircraft engines. In flights with long routes, thrust management function in airplane information system has a structure that ensures altitude and performance management. This study focused on thrust changes throughout all flight were examined by taking into consideration their energy and exergy performances for fuel consumption of an aircraft engine used in flight with long route were taken as reference. The energetic and exergetic performance evaluations were made under the various altitude conditions. The thrust changes for different altitude conditions were obtained to be at 86.53 % in descending direction and at 142.58 % in ascending direction while the energy and exergy efficiency changes for the referenced engine were found to be at 80.77 % and 84.45 %, respectively. The results revealed here can be helpful to manage thrust and reduce fuel consumption, but engine performance will be in accordance with operation requirements.

  16. Approaches to evaluating weathering effects on release of engineered nanomaterials from solid matrices

    Science.gov (United States)

    Increased production and use of engineered nanomaterials (ENMs) over the past decade has increased the potential for the transport and release of these materials into the environment. Here we present results of two separate studies designed to simulate the effects of weathering o...

  17. Facebook and the engineering of connectivity: a multi-layered approach to social media platforms

    NARCIS (Netherlands)

    van Dijck, J.

    2013-01-01

    This article aims to explain how Web 2.0 platforms in general, and Facebook in particular, engineers online connections. Connectivity has become the material and metaphorical wiring of our culture, a culture in which technologies shape and are shaped not only by economic and legal frames, but also

  18. Application of the Total Quality Management Approach Principles and the ISO 9000 Standards in Engineering Education.

    Science.gov (United States)

    Waks, Shlomo; Frank, Moti

    1999-01-01

    Discusses the applicability of the definition, principles, and underlying strategies of total quality management (TQM) for engineering education. Describes several tools and methods for the implementation of TQM and its suitability for a variety of school activities. Presents a TQM course outline combining lectures, discussions, suggested…

  19. SysML for systems engineering a model-based approach

    CERN Document Server

    Holt, Jon

    2013-01-01

    This new edition of this popular text has been fully updated to reflect SysML 1.3, the latest version of the standard, and the discussion has been extended to show the power of SysML as a tool for systems engineering in an MBSE context.

  20. The Chemical Engineer's Toolbox: A Glass Box Approach to Numerical Problem Solving

    Science.gov (United States)

    Coronell, Daniel G.; Hariri, M. Hossein

    2009-01-01

    Computer programming in undergraduate engineering education all too often begins and ends with the freshman programming course. Improvements in computer technology and curriculum revision have improved this situation, but often at the expense of the students' learning due to the use of commercial "black box" software. This paper describes the…

  1. Inkjet Gene Printing: A Novel Approach to Achieve Gene Modified Cells for Tissue Engineering

    Science.gov (United States)

    2008-12-01

    and pIRES-VEGF-GFP (BD Biosciences, Bedford, MA) encoding the cDNAs of jellyfish Aequorea victoria green fluorescent protein, driven by the...Engineering C-Biomimetic and Supramolecular Systems, 27, 372-376. Cartagena, J., Personal communication: HP R&D, ISB Americas . Dang, J. M., and K. W

  2. Women in Science, Mathematics, Engineering, and Technology: An Experimental Approach in an Undergraduate Course

    Science.gov (United States)

    Benjamin, Diane

    2005-01-01

    The author's primary purpose of this article is to share her working process--that is, the organization of a three-credit undergraduate course entitled Women in Science and Engineering, as well as the design and development of its curriculum, pedagogy, and methodology--and to reflect upon the results. To give life to this structure, a variety of…

  3. Facebook and the engineering of connectivity: a multi-layered approach to social media platforms

    NARCIS (Netherlands)

    van Dijck, J.

    2013-01-01

    This article aims to explain how Web 2.0 platforms in general, and Facebook in particular, engineers online connections. Connectivity has become the material and metaphorical wiring of our culture, a culture in which technologies shape and are shaped not only by economic and legal frames, but also b

  4. Tissue-engineered mandibular bone reconstruction for continuity defects: a systematic approach to the literature

    NARCIS (Netherlands)

    Chanchareonsook, N.; Junker, R.; Jongpaiboonkit, L.; Jansen, J.A.

    2014-01-01

    Background: Despite significant surgical advances over the last decades, segmental mandibular bone repair remains a challenge. In light of this, tissue engineering might offer a next step in the evolution of mandibular reconstruction. Purpose: The purpose of the present report was to (1) systematica

  5. Establishing the Overall Service Quality of Engineering Education: Fuzzy Logic Approach

    Science.gov (United States)

    Shekhar, N. Chandra; Venkatasubbaiah, K.; Kandukuria, N. R.

    2012-01-01

    Measuring overall service quality (OSQ) is gaining prominence in higher education due to the increased competition among engineering education institutions (EEIs) and growing awareness about value for money among the public. Determination of OSQ on certain institutional aspects is done by various agencies throughout the world. Each system uses a…

  6. Composite adaptive and input observer-based approaches to the cylinder flow estimation in spark ignition automotive engines

    Energy Technology Data Exchange (ETDEWEB)

    Stotsky, A.; Eriksson, S. [Volvo Car Corporation, Gothenburg (Sweden). Engine Design and Development Dept.; Kolmanovsky, I. [Ford Motor Co., Dearborn, MI (United States)

    2004-07-01

    The performance of air charge estimation algorithms in spark ignition automotive engines can be enhanced using advanced estimation techniques available in the controls literature. This paper illustrates two approaches of this kind that can improve the cylinder flow estimation for gasoline engines without external exhaust gas recirculation (EGR). The first approach is based on an input observer, while the second approach relies on an adaptive estimator. Assuming that the cylinder flow is nominally estimated via a speed-density calculation, and that the uncertainty is additive to the volumetric efficiency, the straightforward application of an input observer provides an easy to implement algorithm that corrects the nominal air flow estimate. The experimental results that we report in the paper point to a sufficiently good transient behaviour of the estimator. The signal quality may deteriorate, however, for extremely fast transients. This motivates the development of an adaptive estimator that relies mostly on the feedforward speed-density calculation during transients, while during engine operation close to steady-state conditions, it relies mostly on the adaptation. In our derivation of the adaptive estimator, the uncertainty is modelled as an unknown parameter multiplying the intake manifold temperature. We use the tracking error between the measured and modelled intake manifold pressure together with an appropriately defined prediction error estimate to develop an adaptation algorithm with improved identifiability and convergence rate. A robustness enhancement, via a {sigma}-modification with the {sigma}-factor depending on the prediction error estimate, ensures that in transients the parameter estimate converges to a predetermined a priori value. In close to steady-state conditions, the {sigma}-modification is rendered inactive and the evolution of the parameter estimate is determined by both tracking error and prediction error estimate. Further enhancements are

  7. An approach for environmental risk assessment of engineered nanomaterials using Analytical Hierarchy Process (AHP) and fuzzy inference rules.

    Science.gov (United States)

    Topuz, Emel; van Gestel, Cornelis A M

    2016-01-01

    The usage of Engineered Nanoparticles (ENPs) in consumer products is relatively new and there is a need to conduct environmental risk assessment (ERA) to evaluate their impacts on the environment. However, alternative approaches are required for ERA of ENPs because of the huge gap in data and knowledge compared to conventional pollutants and their unique properties that make it difficult to apply existing approaches. This study aims to propose an ERA approach for ENPs by integrating Analytical Hierarchy Process (AHP) and fuzzy inference models which provide a systematic evaluation of risk factors and reducing uncertainty about the data and information, respectively. Risk is assumed to be the combination of occurrence likelihood, exposure potential and toxic effects in the environment. A hierarchy was established to evaluate the sub factors of these components. Evaluation was made with fuzzy numbers to reduce uncertainty and incorporate the expert judgements. Overall score of each component was combined with fuzzy inference rules by using expert judgements. Proposed approach reports the risk class and its membership degree such as Minor (0.7). Therefore, results are precise and helpful to determine the risk management strategies. Moreover, priority weights calculated by comparing the risk factors based on their importance for the risk enable users to understand which factor is effective on the risk. Proposed approach was applied for Ag (two nanoparticles with different coating) and TiO2 nanoparticles for different case studies. Results verified the proposed benefits of the approach.

  8. AN ALGORITHMIC AND SOFTWARE ENGINEERING BASED APPROACH TO ROBUST VIDEO GAME DESIGN

    Directory of Open Access Journals (Sweden)

    Hollie Boudreaux

    2011-08-01

    Full Text Available Design and development of a large video game is a challenging software engineering and projectmanagement problem. Thus, it is a non-trivial task. This paper describes the design and development of agame, entitled N-STAL, which embodies nearly every aspect of game design and implementation,including researching, crafting of assets, selection and usage of proper tools, software development,testing, and team play. Key software engineering principles are followed throughout the design,development, and validation stages. Successful execution of such design and development in an academicsetting inspires team-based learning in students. It challenges them to meet project deadlines, preparesthem for life-long learning, and helps them understand some of the challenges that are faced withmodeling, simulation, and user interfacing.

  9. A New Approach to Design Graph Based Search Engine for Multiple Domains Using Different Ontologies

    CERN Document Server

    Mukhopadhyay, Debajyoti

    2011-01-01

    Search Engine has become a major tool for searching any information from the World Wide Web (WWW). While searching the huge digital library available in the WWW, every effort is made to retrieve the most relevant results. But in WWW majority of the Web pages are in HTML format and there are no such tags which tells the crawler to find any specific domain. To find more relevant result we use Ontology for that particular domain. If we are working with multiple domains then we use multiple ontologies. Now in order to design a domain specific search engine for multiple domains, crawler must crawl through the domain specific Web pages in the WWW according to the predefined ontologies.

  10. Optimal Configuration of Human Motion Tracking Systems: A Systems Engineering Approach

    Science.gov (United States)

    Henderson, Steve

    2005-01-01

    Human motion tracking systems represent a crucial technology in the area of modeling and simulation. These systems, which allow engineers to capture human motion for study or replication in virtual environments, have broad applications in several research disciplines including human engineering, robotics, and psychology. These systems are based on several sensing paradigms, including electro-magnetic, infrared, and visual recognition. Each of these paradigms requires specialized environments and hardware configurations to optimize performance of the human motion tracking system. Ideally, these systems are used in a laboratory or other facility that was designed to accommodate the particular sensing technology. For example, electromagnetic systems are highly vulnerable to interference from metallic objects, and should be used in a specialized lab free of metal components.

  11. Trends and approaches in N-Glycosylation engineering in Chinese hamster ovary cell culture

    DEFF Research Database (Denmark)

    Fan, Yuzhou; Kildegaard, Helene Faustrup; Andersen, Mikael Rørdam

    , in particular, of those as drug substances, is extremely concerned in drug development andapproval, as it will largely affect their stability, efficacy, clearance rate and immunogenicity. Therefore to engineering N-glycosylationof CHO cell-derived recombinant proteins are extremely important. Here, we...... will summarize a group of recent strategies andapproaches and come up with case studies for N-glycosylation engineering in CHO cells and show several examples of relevantstudy cases from our research: 1) media and feed design, 2) culture process optimization, 3) substrate addition, 4) geneticengineering, 5......Chinese hamster ovary (CHO) cells have become the preferred expression system for the production of complex recombinantglycoproteins. It has been historically successful in industrial scale-up application and in generating human-like protein glycosylation.N-glycosylation of recombinant proteins...

  12. Philosophical Approach to Engineering Education Under the Introduction of the Smart Grid Concept in Russia

    Directory of Open Access Journals (Sweden)

    Makienko Marina A.

    2015-01-01

    Full Text Available The development of power industry in the world today is driven by two main trends: the search for renewable energy sources and their use and the energy efficiency which require the development of smart grids. This paper brings up the issue of staff training for professional development of the Smart Grid technology and for use of its elements by customers in households. The problem of consumer readiness for the use of smart meters was studied. It was revealed that the considerable part of the respondents was not familiar with the definition of Smart Grid. That required the development of communication skills by energy engineering students and their social activity as well. The reasons mentioned make actual the following elements of engineering education: social responsibility, stress resistance, ability to forecast the future.

  13. Multimedia Environmental Fate and Speciation of Engineered Nanoparticles: A Probabilistic Modeling Approach

    OpenAIRE

    Meesters, J.A.J.; Quik, J.T.K.; Koelmans, A.A.; Hendriks, A.J.; Meent, D. van de

    2016-01-01

    The robustness of novel multimedia fate models in environmental exposure estimation of engineered nanoparticles (ENPs) remains unclear, because of uncertainties in the emission, physicochemical properties and natural variability in environmental systems. Here, we evaluate the uncertainty in predicted environmental concentrations (PECs) by using the SimpleBox4nano (SB4N) model. Monte Carlo (MC) simulations were performed on the environmental fate, concentrations and speciation of nano-CeO2, -T...

  14. Combustion Control of Diesel Engine using Feedback Error Learning with Kernel Online Learning Approach

    Science.gov (United States)

    Widayaka, Elfady Satya; Ohmori, Hiromitsu

    2016-09-01

    This paper shows how to design Multivariable Model Reference Adaptive Control System (MRACS) for “Tokyo University discrete-time engine model” proposed by Yasuda et al (2014). This controller configuration has the structure of “Feedback error learning (FEL)” and adaptive law is based on kernel method. Simulation results indicate that “kernelized” adaptive controllers can improve the tracking performance, the speed of convergence and the robustness to disturbances.

  15. An analysis of the aircraft engine Component Improvement Program (CIP) : a life cycle cost approach

    OpenAIRE

    Borer, Chris Joseph

    1990-01-01

    Approved for public release; distribution unlimited. Increasing budgetary constraints have prompted actions to reduce the maintenance cost of current naval aircraft. This thesis examines the Aircraft Engine Component Improvement Program (CIP), its impact on these cost at the organizational and intermediate levels of maintenance, and savings from these improvements. The objectives of the research were to identify current life cycle cost (LCC) models used by the Navy andor the other services...

  16. A modern approach to storing of 3D geometry of objects in machine engineering industry

    Science.gov (United States)

    Sokolova, E. A.; Aslanov, G. A.; Sokolov, A. A.

    2017-02-01

    3D graphics is a kind of computer graphics which has absorbed a lot from the vector and raster computer graphics. It is used in interior design projects, architectural projects, advertising, while creating educational computer programs, movies, visual images of parts and products in engineering, etc. 3D computer graphics allows one to create 3D scenes along with simulation of light conditions and setting up standpoints.

  17. Interleukin 7-engineered stromal cells: a new approach for hastening naive T cell recruitment.

    Science.gov (United States)

    Di Ianni, Mauro; Del Papa, Beatrice; De Ioanni, Maria; Terenzi, Adelmo; Sportoletti, Paolo; Moretti, Lorenzo; Falzetti, Franca; Gaozza, Eugenia; Zei, Tiziana; Spinozzi, Fabrizio; Bagnis, Claude; Mannoni, Patrice; Bonifacio, Elisabetta; Falini, Brunangelo; Martelli, Massimo F; Tabilio, Antonio

    2005-06-01

    In this study we determined whether human stromal cells could be engineered with a retroviral vector carrying the interleukin 7 (IL-7) gene and investigated the effects on T cells in vitro and in vivo in a murine model. Transduced mesenchymal cells strongly express CD90 (98.15%), CD105 (87.6%), and STRO-1 (86.7%). IL-7 production was 16.37 (+/-2 SD) pg/ml, which remained stable for 60 days. In vitro-immunoselected naive T cells maintained the CD45RA+ CD45RO- naive phenotype (4.2 times more than controls) after 7 days of culture with IL-7-engineered stromal cells. The apoptosis rate (4.7%) of the naive T cells cultured with transduced stromal cells overlapped with that of freshly isolated cells. Immunohistological analysis detected stromal cells in bone marrow, spleen, and thymus. Cotransplantation of IL-7-engineered stromal cells with CD34+ cells improved engraftment in terms of CD45+ cells and significantly increased the CD3+ cell count in peripheral blood, bone marrow, and spleen. These data demonstrate the following: (1) human stromal cells can be transduced, generating a normal layer; (2) transduced stromal cells in vitro maintain the naive T cell phenotype; and (3) IL-7-transduced stromal cells in vivo home to lymphoid organs and produce sufficient IL-7 in loco, supporting T cell development in a cotransplantation model. Because of their efficient cytokine production and homing, IL-7-engineered stromal cells might be an ideal vehicle to hasten immunological reconstitution in T cell-depleted hosts.

  18. A Problem-Solving Approach to Teaching Creativity for Engineering and Other Disciplines

    Directory of Open Access Journals (Sweden)

    Chelsey Bradford

    2014-08-01

    Full Text Available Creativity is an integral part in the careers of every professional, including artists, actors, as well as businessmen and engineers. Engineers, the focus of this effort, are traditionally considered to be systematic thinkers and implementers of constrained procedures and algorithms. In order to challenge this perception, ECE490DI is a class designed to show engineering students that their majors and future careers will not only use creativity, but be fully immersed in it. Once the students realize this fact, the next step is to help them discover their own creativity skills and show them that creativity, like other talents, can be nurtured and strengthened through repetitive use. To accomplish these goals, students in ECE490DI take a class trip to renowned theme parks in Orlando, FL, where they attend multiple workshops in the areas of leadership, teamwork, and creativity. The workshops allow students to exercise their leadership, teamwork, and creativity and show them several tools to expand and further improve their abilities in those areas. Students are also given the chance to meet and interact with theme parks' engineers, also known as "Imagineers," to see the practical applications of creativity in a hands-on creative work environment. While the objectives of ECE490DI were successfully met in previous semesters, the class was redesigned to have a broader scope and a multidisciplinary nature. The multidisciplinary version of the class builds on the assessment results of the previous offerings as well as feedback from participating students, faculty members, and theme parks staff members. The new version of the class includes more meetings throughout the semester to further reinforce the ideas and concepts from the workshops.

  19. Effective therapeutic approach for head and neck cancer by an engineered minibody targeting the EGFR receptor.

    Directory of Open Access Journals (Sweden)

    Young Pil Kim

    Full Text Available Cetuximab, a chimeric monoclonal antibody developed for targeting the Epidermal Growth Factor Receptor (EGFR, has been intensively used to treat cancer patients with metastatic colorectal cancer and head and neck cancer. Intact immunoglobulin G (IgG antibody like cetuximab, however, has some limitations such as high production cost and low penetration rate from vasculature into solid tumor mass due to its large size. In attempt to overcome these limitations, we engineered cetuximab to create single chain variable fragments (scFv-CH3; Minibody that were expressed in bacterial system. Among three engineered minibodies, we found that MI061 minibody, which is composed of the variable heavy (VH and light (VL region joined by an 18-residue peptide linker, displays higher solubility and better extraction properties from bacterial lysate. In addition, we validated that purified MI061 significantly interferes ligand binding to EGFR and blocks EGFR's phosphorylation. By using a protein microarray composed of 16,368 unique human proteins covering around 2,400 plasma membrane associated proteins such as receptors and channels, we also demonstrated that MI061 only recognizes the EGFR but not other proteins as compared with cetuximab. These results indicated that engineered MI061 retains both binding specificity and affinity of cetuximab for EGFR. Although it had relatively short half-life in serum, it was shown to be highly significant anti-tumor effect by inhibiting ERK pathway in A431 xenograft model. Taken together, our present study provides compelling evidence that engineered minibody is more effective and promising agent for in vivo targeting of solid tumors.

  20. Using a Formal Approach for Reverse Engineering and Design Recovery to Support Software Reuse

    Science.gov (United States)

    Gannod, Gerald C.

    2002-01-01

    This document describes 3rd year accomplishments and summarizes overall project accomplishments. Included as attachments are all published papers from year three. Note that the budget for this project was discontinued after year two, but that a residual budget from year two allowed minimal continuance into year three. Accomplishments include initial investigations into log-file based reverse engineering, service-based software reuse, and a source to XML generator.

  1. Photonic waveguide engineering using pulsed lasers – A novel approach for non-clean room fabrication!

    OpenAIRE

    Jha, A.; Murray, M; Irranejad, M.; Zhao, Z.; Fernandez, TT; Hogg, RA; Zhang, ZY; Bamiedakis, N; Plenty, RV; White, IH

    2015-01-01

    This is the accepted manuscript. The final version is available from IEEE at http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6876466. Over the last 25 years has seen an unprecedented increase in the growth of phonic components based on semiconductor and solid-state lasers, glass and polymer based optical fibres, and organic LEDs. Emerging technology for component engineering must embed dissimilar materials based devices into an integrated form which is more efficient. In this...

  2. Detecting Injector Deactivation Failure Modes in Diesel Engines Using Time and Order Domain Approaches

    Science.gov (United States)

    2012-09-01

    the engine with respect to the piston’s orientation. This is usally referenced to the piston’s Top Dead Center ( TDC ) location of 0 degrees. Top...duration (∆T) and the relative delay/offset from Top Dead Center ( TDC ) for each respective pulse profile event occurring during the record set. In...cylinder three injector misfire. This plot is predicated on the fact the algorithm has identified TDC of cylinder one. Once the cylinder one TDC is

  3. A tool-mediated cognitive apprenticeship approach for a computer engineering course

    OpenAIRE

    Murray, Sarah; Ryan, James; Pahl, Claus

    2003-01-01

    Teaching database engineers involves a variety of learning activities. A strong focus is on practical problems that go beyond the acquisition of knowledge. Skills and experience are equally important. We propose a virtual apprenticeship model for the knowledge- and skillsoriented Web-based education of database students. We adapt the classical cognitive apprenticeship theory to the Web context utilising scaffolding and activity theory. The choice of educational media and the forms of student ...

  4. Software Engineering Environments for Mission Critical Applications -- STARS Alternative Programmatic Approaches.

    Science.gov (United States)

    1984-08-01

    Tools by B. Kernighan and T. Plauger (Prentice-Hall, 1975) and the paper "A Software Engineering Environment for Weapon System Software" by H. Steubing...DoD use. Examples of some available and soon to be available environments include Xerox Development Environment (XDE), Unix , ITT Programming Support...VMS (TM), and some implementations of AT&T’s UNIX (TM) or UNIX -look- alikes are the prime examples. Some of these might be used as the base

  5. Advances in combining gene therapy with cell and tissue engineering-based approaches to enhance healing of the meniscus.

    Science.gov (United States)

    Cucchiarini, M; McNulty, A L; Mauck, R L; Setton, L A; Guilak, F; Madry, H

    2016-08-01

    Meniscal lesions are common problems in orthopaedic surgery and sports medicine, and injury or loss of the meniscus accelerates the onset of knee osteoarthritis (OA). Despite a variety of therapeutic options in the clinics, there is a critical need for improved treatments to enhance meniscal repair. In this regard, combining gene-, cell-, and tissue engineering-based approaches is an attractive strategy to generate novel, effective therapies to treat meniscal lesions. In the present work, we provide an overview of the tools currently available to improve meniscal repair and discuss the progress and remaining challenges for potential future translation in patients.

  6. Active Learning Strategies: An illustrative approach to bring out better learning outcomes from Science, Technology, Engineering and Mathematics (STEM) students

    OpenAIRE

    Adusumilli Srinath

    2014-01-01

    Teaching in a Teacher centric manner has been the mainframe teaching style in engineering education, however students feel it as a single sided approach and feel they are only passive listeners thus this style has now paved way to a Learner centric style of teaching-learning which is ACTIVE LEARNING, wherein every student is actively involved in one or the other form of learning and thus gets a chance to develop the key aspects of the course either on their own or by being a member of an acti...

  7. TOPSIS Multi-Criteria Decision Modeling Approach for Biolubricant Selection for Two-Stroke Petrol Engines

    Directory of Open Access Journals (Sweden)

    Masoud Dehghani Soufi

    2015-12-01

    Full Text Available Exhaust pollutants from two-stroke petrol engines are a problem for the environment. Biolubricants are a new generation of renewable and eco-friendly vegetable-based lubricants, which have attracted a lot of attention in recent years. In this paper, the applicability of the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS method to support the process of building the scoring system for selecting an appropriate two-stroke lubricant has been analyzed. For this purpose, biolubricants (TMP-triesters based on castor oil, palm oil, and waste cooking oil were produced and then utilized in a 200 cc two-stroke gasoline engine to investigate their effects on its performance and exhaust emissions. The results obtained from the use of the entropy technique in the TOPSIS algorithm showed that palm oil-based lubricant took up the greatest distance from the Negative Ideal Solution (NIS and was selected as the most optimal lubricant for these types of engines.

  8. A Comparison of Hybrid Approaches for Turbofan Engine Gas Path Fault Diagnosis

    Science.gov (United States)

    Lu, Feng; Wang, Yafan; Huang, Jinquan; Wang, Qihang

    2016-09-01

    A hybrid diagnostic method utilizing Extended Kalman Filter (EKF) and Adaptive Genetic Algorithm (AGA) is presented for performance degradation estimation and sensor anomaly detection of turbofan engine. The EKF is used to estimate engine component performance degradation for gas path fault diagnosis. The AGA is introduced in the integrated architecture and applied for sensor bias detection. The contributions of this work are the comparisons of Kalman Filters (KF)-AGA algorithms and Neural Networks (NN)-AGA algorithms with a unified framework for gas path fault diagnosis. The NN needs to be trained off-line with a large number of prior fault mode data. When new fault mode occurs, estimation accuracy by the NN evidently decreases. However, the application of the Linearized Kalman Filter (LKF) and EKF will not be restricted in such case. The crossover factor and the mutation factor are adapted to the fitness function at each generation in the AGA, and it consumes less time to search for the optimal sensor bias value compared to the Genetic Algorithm (GA). In a word, we conclude that the hybrid EKF-AGA algorithm is the best choice for gas path fault diagnosis of turbofan engine among the algorithms discussed.

  9. An approach to architecture 3D scaffold with interconnective microchannel networks inducing angiogenesis for tissue engineering.

    Science.gov (United States)

    Sun, Jiaoxia; Wang, Yuanliang; Qian, Zhiyong; Hu, Chenbo

    2011-11-01

    The angiogenesis of 3D scaffold is one of the major current limitations in clinical practice tissue engineering. The new strategy of construction 3D scaffold with microchannel circulation network may improve angiogenesis. In this study, 3D poly(D: ,L: -lactic acid) scaffolds with controllable microchannel structures were fabricated using sacrificial sugar structures. Melt drawing sugar-fiber network produced by a modified filament spiral winding method was used to form the microchannel with adjustable diameters and porosity. This fabrication process was rapid, inexpensive, and highly scalable. The porosity, microchannel diameter, interconnectivity and surface topographies of the scaffold were characterized by scanning electron microscopy. Mechanical properties were evaluated by compression tests. The mean porosity values of the scaffolds were in the 65-78% and the scaffold exhibited microchannel structure with diameter in the 100-200 μm range. The results showed that the scaffolds exhibited an adequate porosity, interconnective microchannel network, and mechanical properties. The cell culture studies with endothelial cells (ECs) demonstrated that the scaffold allowed cells to proliferate and penetrate into the volume of the entire scaffold. Overall, these findings suggest that the fabrication process offers significant advantages and flexibility in generating a variety of non-cytotoxic tissue engineering scaffolds with controllable distributions of porosity and physical properties that could provide the necessary physical cues for ECs and further improve angiogenesis for tissue engineering.

  10. Gas turbine engine prognostics using Bayesian hierarchical models: A variational approach

    Science.gov (United States)

    Zaidan, Martha A.; Mills, Andrew R.; Harrison, Robert F.; Fleming, Peter J.

    2016-03-01

    Prognostics is an emerging requirement of modern health monitoring that aims to increase the fidelity of failure-time predictions by the appropriate use of sensory and reliability information. In the aerospace industry it is a key technology to reduce life-cycle costs, improve reliability and asset availability for a diverse fleet of gas turbine engines. In this work, a Bayesian hierarchical model is selected to utilise fleet data from multiple assets to perform probabilistic estimation of remaining useful life (RUL) for civil aerospace gas turbine engines. The hierarchical formulation allows Bayesian updates of an individual predictive model to be made, based upon data received asynchronously from a fleet of assets with different in-service lives and for the entry of new assets into the fleet. In this paper, variational inference is applied to the hierarchical formulation to overcome the computational and convergence concerns that are raised by the numerical sampling techniques needed for inference in the original formulation. The algorithm is tested on synthetic data, where the quality of approximation is shown to be satisfactory with respect to prediction performance, computational speed, and ease of use. A case study of in-service gas turbine engine data demonstrates the value of integrating fleet data for accurately predicting degradation trajectories of assets.

  11. General approach for engineering small-molecule-binding DNA split aptamers.

    Science.gov (United States)

    Kent, Alexandra D; Spiropulos, Nicholas G; Heemstra, Jennifer M

    2013-10-15

    Here we report a general method for engineering three-way junction DNA aptamers into split aptamers. Split aptamers show significant potential for use as recognition elements in biosensing applications, but reliable methods for generating these sequences are currently lacking. We hypothesize that the three-way junction is a "privileged architecture" for the elaboration of aptamers into split aptamers, as it provides two potential splitting sites that are distal from the target binding pocket. We propose a general method for split aptamer engineering that involves removing one loop region, then systematically modifying the number of base pairs in the remaining stem regions in order to achieve selective assembly only in the presence of the target small molecule. We screen putative split aptamer sequence pairs using split aptamer proximity ligation (StAPL) technology developed by our laboratory, but we validate that the results obtained using StAPL translate directly to systems in which the aptamer fragments are assembling noncovalently. We introduce four new split aptamer sequences, which triples the number of small-molecule-binding DNA split aptamers reported to date, and the methods described herein provide a reliable route for the engineering of additional split aptamers, dramatically advancing the potential substrate scope of DNA assembly based biosensors.

  12. An innovative approach for combustion assessment of an high performance engine, based in cylce-resolved pressure indicating technology

    Energy Technology Data Exchange (ETDEWEB)

    Mammetti, M.; Marcigliano, F.; Cipolla, G. [Ferrari S.p.A., Maranello (Italy)

    2002-07-01

    Cycle-to-cycle and cylinderto-cylinder stochastic variation is ''stressed'' in high performance engines by analyzing the pressure traces and angular velocity signals. The wide operating range (min-to-max load vs rotational speed) of such engines causes a much more difficult optimization for the coefficient of variation (COV) of IMEP especially at low loads. The COV of IMEP has very bad effects on the NVH overall behaviour generally related to high fuel consumption and emissions at part load and reduces performance at full load, moreover it inhibits a cood combustion diagnostic (i.e. misfiring detection) for an board diagnostics (EOBD/OBD II). The experimental indicating pressure traces and the resulting IMEP for individual cylinder in each cycle has been processed in order to extract the main statistical features through ensemble-averaged and cycle resolved approach for new V8/4.2 l engine of Maserati Spyder. For data processing different tools have been used in order to properly evaluate the stability of the combustion by means of the investigation of the angular velocity signals especially for the diagnosis of misfiring events. (orig.)

  13. Conceptual and Procedural Approaches to Mathematics in the Engineering Curriculum--Comparing Views of Junior and Senior Engineering Students in Two Countries

    Science.gov (United States)

    Bergsten, Christer; Engelbrecht, Johann; Kågesten, Owe

    2017-01-01

    One challenge for an optimal design of the mathematical components in engineering education curricula is to understand how the procedural and conceptual dimensions of mathematical work can be matched with different demands and contexts from the education and practice of engineers. The focus in this paper is on how engineering students respond to…

  14. The Formation of Conservation-Based Behaviour of Mechanical Engineering Students through Contextual Learning Approach

    Science.gov (United States)

    Sudarman; Djuniadi; Sutopo, Yeri

    2017-01-01

    This study was aimed to figure out: (1) the implementation of contextual learning approaches; (2) the learning outcome of conservation education using contextual approach on the internship program preparation class; (3) the conservation-based behaviour of the internship program participants; (4) the contribution of conservation education results…

  15. A personalized and control systems engineering conceptual approach to target childhood anxiety in the contexts of cultural diversity.

    Science.gov (United States)

    Pina, Armando A; Holly, Lindsay E; Zerr, Argero A; Rivera, Daniel E

    2014-01-01

    In the child and adolescent anxiety area, some progress has been made to develop evidence-based prevention protocols, but less is known about how to best target these problems in children and families of color. In general, data show differential program effects with some minority children benefiting significantly less. Our preliminary data, however, show promise and suggest cultural parameters to consider in the tailoring process beyond language and cultural symbols. It appears that a more focused approach to culture might help activate intervention components and its intended effects by focusing, for example, on the various facets of familismo when working with some Mexican parents. However, testing the effects and nuances of cultural adaption vis-à-vis a focused personalized approach is methodologically challenging. For this reason, we identify control systems engineering design methods and provide example scenarios relevant to our data and recent intervention work.

  16. A Practice Approach to Software Engineering Teaching%软件工程实践教学方法探索

    Institute of Scientific and Technical Information of China (English)

    曾红卫; 刘悦; 刘炜

    2011-01-01

    Based on our teaching experience, this paper analyses the existing problems in the practical teaching of software engineering. According to the programme of the course, we propose that the practice for software engineering teaching should be partitioned into two stages: specific task experiment and practice for project development. The former aims at mastering the theory of software engineering by practicing the key knowledge points of some software development method. The latter aims at training the students' basic skills for the software development practice. It is performed in the form of team, and gives the students opportunities for applying comprehensively software engineering approach to the practical software development.%本文结合教学体会,分析了软件工程实验教学中存在的问题.紧扣教学计划,以学生的知识和能力为基础,建议将软件工程实践分为专项任务实验和项目开发实践两个阶段.专项任务实验针对软件开发方法的主要知识点,以巩固软件工程理论知识为目的;项目开发实践以小组形式进行实际软件项目的开发,培养学生的软件工程方法综合运用能力和基本的软件开发实践能力.

  17. Suggested approach for establishing a rehabilitation engineering information service for the state of California

    Science.gov (United States)

    Christy, L. F.; Kelton-Fogg, G.; Lizak, R.; Vahlkamp, C.

    1978-01-01

    An ever expanding body of rehabilitation engineering technology is developing in this country, but it rarely reaches the people for whom it is intended. The increasing concern of state and federal departments of rehabilitation for this technology lag was the stimulus for a series of problem-solving workshops held in California during 1977. As a result of the workshops, the recommendation emerged that the California Department of Rehabilitation take the lead in the development of a coordinated delivery system that would eventually serve the entire state and be a model for similar systems across the nation.

  18. Biomaterial-engineering and neurobiological approaches for regenerating the injured cerebral cortex

    Directory of Open Access Journals (Sweden)

    Itsuki Ajioka

    2016-03-01

    Full Text Available The cerebral cortex is responsible for higher functions of the central nervous system (CNS, such as movement, sensation, and cognition. When the cerebral cortex is severely injured, these functions are irreversibly impaired. Although recent neurobiological studies reveal that the cortex has the potential for regeneration, therapies for functional recovery face some technological obstacles. Biomaterials have been used to evoke regenerative potential and promote regeneration in several tissues, including the CNS. This review presents a brief overview of new therapeutic strategies for cortical regeneration from the perspectives of neurobiology and biomaterial engineering, and discusses a promising technology for evoking the regenerative potential of the cerebral cortex.

  19. A systems engineering approach to automated failure cause diagnosis in space power systems

    Science.gov (United States)

    Dolce, James L.; Faymon, Karl A.

    1987-01-01

    Automatic failure-cause diagnosis is a key element in autonomous operation of space power systems such as Space Station's. A rule-based diagnostic system has been developed for determining the cause of degraded performance. The knowledge required for such diagnosis is elicited from the system engineering process by using traditional failure analysis techniques. Symptoms, failures, causes, and detector information are represented with structured data; and diagnostic procedural knowledge is represented with rules. Detected symptoms instantiate failure modes and possible causes consistent with currently held beliefs about the likelihood of the cause. A diagnosis concludes with an explanation of the observed symptoms in terms of a chain of possible causes and subcauses.

  20. Engineering the path to higher-order thinking in elementary education: A problem-based learning approach for STEM integration

    Science.gov (United States)

    Rehmat, Abeera Parvaiz

    As we progress into the 21st century, higher-order thinking skills and achievement in science and math are essential to meet the educational requirement of STEM careers. Educators need to think of innovative ways to engage and prepare students for current and future challenges while cultivating an interest among students in STEM disciplines. An instructional pedagogy that can capture students' attention, support interdisciplinary STEM practices, and foster higher-order thinking skills is problem-based learning. Problem-based learning embedded in the social constructivist view of teaching and learning (Savery & Duffy, 1995) promotes self-regulated learning that is enhanced through exploration, cooperative social activity, and discourse (Fosnot, 1996). This quasi-experimental mixed methods study was conducted with 98 fourth grade students. The study utilized STEM content assessments, a standardized critical thinking test, STEM attitude survey, PBL questionnaire, and field notes from classroom observations to investigate the impact of problem-based learning on students' content knowledge, critical thinking, and their attitude towards STEM. Subsequently, it explored students' experiences of STEM integration in a PBL environment. The quantitative results revealed a significant difference between groups in regards to their content knowledge, critical thinking skills, and STEM attitude. From the qualitative results, three themes emerged: learning approaches, increased interaction, and design and engineering implementation. From the overall data set, students described the PBL environment to be highly interactive that prompted them to employ multiple approaches, including design and engineering to solve the problem.

  1. Improving the Ranking Capability of the Hyperlink Based Search Engines Using Heuristic Approach

    Directory of Open Access Journals (Sweden)

    Haider A. Ramadhan

    2006-01-01

    Full Text Available To evaluate the informative content of a Web page, the Web structure has to be carefully analyzed. Hyperlink analysis, which is capable of measuring the potential information contained in a Web page with respect to the Web space, is gaining more attention. The links to and from Web pages are an important resource that has largely gone unused in existing search engines. Web pages differ from general text in that they posse’s external and internal structure. The Web links between documents can provide useful information in finding pages for a given set of topics. Making use of the Web link information would allow the construction of more powerful tools for answering user queries. Google has been among the first search engines to utilize hyper links in page ranking. Still two main flaws in Google need to be tackled. First, all the backlinks to a page are assigned equal weights. Second, less content rich pages, such as intermediate and transient pages, are not differentiated from more content rich pages. To overcome these pitfalls, this paper proposes a heuristic based solution to differentiate the significance of various backlinks by assigning a different weight factor to them depending on their location in the directory tree of the Web space.

  2. Wire frame: A reliable approach to build sealed engineering geological models

    Science.gov (United States)

    Xu, Nengxiong; Tian, Hong

    2009-08-01

    The technique of 3D geological modeling (3DGM) is an effective tool for representing complex geological objects. In order to improve the accuracy of geological models applied in numerical simulation methods such as finite elements and finite differences, we can use 3DGM as a modeling tool. To do this, however, 3DGM must provide the ability to model geological and artificial objects in a unified way, and its geological model must be seamless for mesh generation. We present the concept of a sealed engineering geological model (SEGM), and describe its topological representation. Three kinds of conditions: geometric continuity, topological consistency and geological consistency, which must be satisfied by SEGM, are discussed in detail. A new method for constructing an SEGM based on a wire frame is proposed. It includes three main components: wire frame construction, interface modification and reconstruction, and block tracing. Building a unitary wire frame, which is composed of many simple arcs and connects all interfaces seamlessly, is the key of this method. An algorithm, involving two intersections computations and partition of simple arcs, is proposed for building a wire frame. Additionally, we also propose a local iterative algorithm for computing fault traces. As an example, we build an SEGM for the dam area of a hydraulic engineering project in the HuNan province of China.

  3. Comprehensive approach to photonics education for technicians, engineers, and scientists in 4+2+2 programs

    Science.gov (United States)

    Pedrotti, Leno S.; Massa, Nicholas J.; Soulsby, Eric P.; Enderle, John; Roychoudhuri, Chandrasekhar

    1995-10-01

    This paper outlines a curricular plan for the education of photonics technicians, engineers, and scientists in 4 + 2 + 2 programs. These programs begin at the 9th grade in high school and end either at the 14th grade (4 + 2 programs) with an associate of applied science degree, or at the 16th grade (4 + 2 + 2 programs) with a bachelor of science degrees. Beginning with comprehensive lists of appropriate tasks for photonics technicians - as identified by phonics-related industries - extrapolation is made to specific courses, sequences of courses, and suggested programs. The foundations are set in place first in four-year high school programs, with emphasis on basics in mathematics, science, communications and introductory technology courses. The postsecondary level programs, through the 13th and 14th year, present the breadth and depth of skills required for the development of entry-level photonics technicians. Finally articulated programs from two-year colleges on to four-year colleges are outlined for those who opt to continue on for a bachelor of science degree and who plan to enter the phonics workforce with concentration in electrical engineering and/or optics.

  4. A DMAIC approach for process capability improvement an engine crankshaft manufacturing process

    Science.gov (United States)

    Sharma, G. V. S. S.; Rao, P. Srinivasa

    2014-05-01

    The define-measure-analyze-improve-control (DMAIC) approach is a five-strata approach, namely DMAIC. This approach is the scientific approach for reducing the deviations and improving the capability levels of the manufacturing processes. The present work elaborates on DMAIC approach applied in reducing the process variations of the stub-end-hole boring operation of the manufacture of crankshaft. This statistical process control study starts with selection of the critical-to-quality (CTQ) characteristic in the define stratum. The next stratum constitutes the collection of dimensional measurement data of the CTQ characteristic identified. This is followed by the analysis and improvement strata where the various quality control tools like Ishikawa diagram, physical mechanism analysis, failure modes effects analysis and analysis of variance are applied. Finally, the process monitoring charts are deployed at the workplace for regular monitoring and control of the concerned CTQ characteristic. By adopting DMAIC approach, standard deviation is reduced from 0.003 to 0.002. The process potential capability index ( C P) values improved from 1.29 to 2.02 and the process performance capability index ( C PK) values improved from 0.32 to 1.45, respectively.

  5. Solvent engineering for high-quality perovskite solar cell with an efficiency approaching 20%

    Science.gov (United States)

    Wu, Tongyue; Wu, Jihuai; Tu, Yongguang; He, Xin; Lan, Zhang; Huang, Miaoliang; Lin, Jianming

    2017-10-01

    The perovskite layer is the most crucial factor for the high performance perovskite solar cells. Based on solvent engineering, we develop a ternary-mixed-solvent method for the growth of high-quality [Cs0.05(MA0.17FA0.83)0.95Pb(I0.83Br0.17)3] cation-anion-mixed perovskite films by introducing N-methyl-2-pyrrolidone (NMP) into the precursor mixed solution. By controlling rapid nucleation and retarding crystal growth via intermediate phase PbI2-NMP (Lewis acid-base adduct), a dense, large grain, pinhole-free and long charge carrier lifetime perovskite film is obtained. By optimizing the precursor solvent composition, the perovskite solar cell achieves an impressive power conversion efficiency of 19.61% under one-sun illumination. The research presented here provides a facile, low-cost and highly efficient way for the preparation of perovskite solar cells.

  6. A New Approach for Labeling Images Using CAPTCHA in Image Semantic Search Engines

    Directory of Open Access Journals (Sweden)

    Amir Golchini

    2013-07-01

    Full Text Available In this paper, we present PICTCHA as a CAPTCHA system (Completely Automated Public Turing test to tell Computers and Humans Apart. This system is a security tool for recognition of human users and instead of a complex text, it uses image labels as a valuable output. PICTCHA is made by Web images. In order to verify this CAPTCHA, users are obliged to enter two words for labeling (naming a couple of images. In case of convenient names for the images, the presented meaningful names are used for specifying the content of images. Furthermore, meaningful graphics are created for names and images according which we may develop an image semantic search engine. Due to benefiting from images in the proposed system and its architecture, it has higher security level in comparison with other rivals. In experiments with 60 participants, the correctness of PICTCHA words was %98.18 while about %61.26 users verified this challenge successfully.

  7. A requirements engineering approach for improving the quality of diabetes education websites.

    Science.gov (United States)

    Shabestari, Omid; Roudsari, Abdul

    2011-01-01

    Diabetes Mellitus is a major chronic disease with multi-organ involvement and high-cost complications. Although it has been proved that structured education can control the risk of developing these complications, there is big room for improvement in the educational services for these patients. e-learning can be a good solution to fill this gap. Most of the current e-learning solutions for diabetes were designed by computer experts and healthcare professionals but the patients, as end-users of these systems, haven't been deeply involved in the design process. Considering the expectations of the patients, this article investigates a requirement engineering process comparing the level of importance given to different attributes of the e-learning by patients and healthcare professionals. The results of this comparison can be used for improving the currently developed online diabetes education systems.

  8. Engineering safe and secure cyber-physical systems the specification PEARL approach

    CERN Document Server

    Gumzej, Roman

    2016-01-01

    This book introduces the concept of holistic design and development of cyber physical systems to achieve their safe and secure operation. It shows that by following the standards for embedded system’s safety and using appropriate hardware and software components inherently safe system’s architectures can be devised and certified. While the standards already enable testing and certification of inherently safe and sound hardware, this is still not the case with software. The book demonstrates that Specification PEARL(SPEARL) addresses this issue and proposes appropriate solutions from the viewpoints of software engineering as well as concrete program components. By doing so it reduces the complexity of cyber physical systems design in an innovative way. Three ultimate goals are being followed in the course of defining this new PEARL standard, namely: 1. simplicity over complexity, 2. inherent real-time ability, and 3. conformity to safety integrity and security capability levels.

  9. Establishing the overall service quality of engineering education: fuzzy logic approach

    Science.gov (United States)

    Shekhar, N. Chandra; Venkatasubbaiah, K.; Kandukuria, N. R.

    2012-12-01

    Measuring overall service quality (OSQ) is gaining prominence in higher education due to the increased competition among engineering education institutions (EEIs) and growing awareness about value for money among the public. Determination of OSQ on certain institutional aspects is done by various agencies throughout the world. Each system uses a different set of weighted indicators to measure the overall service quality of institutions. Five service quality factors, namely professionalism, integrated education, facilities, responsiveness and empathy are considered in the study. Trapezoidal fuzzy numbers are used to determine the aggregate weights of the factors to handle the vagueness present in the linguistic values of the stakeholders' subjective opinions. Final weights of the factors are assessed by taking the distances of each factor between Fuzzy Positive Ideal Rating and Fuzzy Negative Ideal Rating. An illustrative study is presented to determine the OSQ of EEIs. The results help to focus on the factors which need immediate attention to enhance the quality of EEIs.

  10. Effects of system-bath coupling on Photosynthetic heat engine: A polaron master equation approach

    CERN Document Server

    Qin, M; Zhao, X L; Yi, X X

    2016-01-01

    In this paper, we apply the polaron master equation, which offers the possibilities to interpolate between weak and strong system-bath coupling, to study how system-bath couplings affect charge transfer processes in Photosystem II reaction center (PSII RC) inspired quantum heat engine (QHE) model in a wide parameter range. The effects of bath correlation and temperature, together with the combined effects of these factors are also discussed in details. The results show a variety of dynamical behaviours. We interpret these results in terms of noise-assisted transport effect and dynamical localization which correspond to two mechanisms underpinning the transfer process in photosynthetic complexes: One is resonance energy transfer and the other is dynamical localization effect captured by the polaron master equation. The effects of system-bath coupling and bath correlation are incorporated in the effective system-bath coupling strength determining whether noise-assisted transport effect or dynamical localization...

  11. Unifying the Classical Approach with New Technologies: An Innovative Proposal for Teaching Mathematics in Engineering

    Directory of Open Access Journals (Sweden)

    Sergio Amat

    2015-08-01

    Full Text Available The aim of this paper is to present a teaching experience developed in the Polytechnic University of Cartagena and, more specifically, in the subject of Mathematical Methods Applied to Civil Engineering, that belongs to the Master Degree of Paths, Channels and Ports. Our classes were a mix between the traditional system and the new educational system. Moreover, we tried to adapt the evaluation process to the new European Framework for Higher Education. We have used videos developed by us and by students in our classes. We have noticed that the interest and motivation in class has grown. Also the grades have improved. We did a survey during this academic year and the results were strongly positive for both students and teachers.

  12. Thermodynamic optimization of a Penrose process: an engineers' approach to black hole thermodynamics

    CERN Document Server

    Bravetti, Alessandro; Lopez-Monsalvo, Cesar S

    2015-01-01

    In this work we present a new view on the thermodynamics of black holes introducing effects of irreversibility by employing thermodynamic optimization and finite-time thermodynamics. These questions are of importance both in physics and in engineering, combining standard thermodynamics with optimal control theory in order to find optimal protocols and bounds for realistic processes without assuming anything about the microphysics involved. We find general bounds on the maximum work and the efficiency of thermodynamic processes involving black holes that can be derived exclusively from the knowledge of thermodynamic relations at equilibrium. Since these new bounds consider the finite duration of the processes, they are more realistic and stringent than their reversible counterparts. To illustrate our arguments, we consider in detail the thermodynamic optimization of a Penrose process, i.e. the problem of finding the least dissipative process extracting all the angular momentum from a Kerr black hole in finite ...

  13. Crosslinked fibrin gels for tissue engineering: two approaches to improve their properties.

    Science.gov (United States)

    Gamboa-Martínez, Tatiana C; Luque-Guillén, Victoria; González-García, Cristina; Gómez Ribelles, José Luis; Gallego-Ferrer, Gloria

    2015-02-01

    Fibrin is a protein that can be used as an ideal scaffolding material to promote tissue regeneration. In order to enhance its physical properties in this study a natural crosslinker, genipin (GP), was employed with the aim to obtain a hydrogel with tuneable properties for tissue engineering applications. The fibrin gel was crosslinked by two different methods using four concentrations of GP to get a stable hydrogel network. Crosslinking density, mechanical properties, swelling, and enzymatic degradation of the hydrogels were tested for each GP content and method employed. The method I: Crosslinking after gel formation promotes a high crosslinking and retains the gel shape for long term whilst the method II: Simultaneous gel formation and crosslinking improves the mechanical properties of the gel. This study confirms the use of GP at different concentrations as a suitable crosslinker of fibrin that promotes the cellular viability of L929 for 21 days of in vitro culture.

  14. Factors affecting students' satisfaction in engineering disciplines: traditional vs. blended approaches

    Science.gov (United States)

    Martínez-Caro, Eva; Campuzano-Bolarín, Francisco

    2011-10-01

    In this paper a two-year field study was carried out to analyse how satisfaction differs across the traditional and blended learning methods. Altogether, 21 courses for graduate and postgraduate engineering students were evaluated. Several variables and their relationship with student satisfaction in the first year, with all courses delivered in traditional mode, were compared with student satisfaction in the second year, which had the same courses delivered in blended mode. Results suggest that student satisfaction is greater in blended courses than in face-to-face courses. This can be explained because the levels of class attendance, motivation and collaboration with classmates were higher in blended learning than in classroom instruction. In addition, class attendance, access to teachers, collaboration with classmates and motivation were found to be leading predictors of student satisfaction in blended environments.

  15. Early Experiences in Traffic Engineering Exploiting Path Diversity: A Practical Approach

    CERN Document Server

    Muscariello, Luca

    2008-01-01

    Recent literature has proved that stable dynamic routing algorithms have solid theoretical foundation that makes them suitable to be implemented in a real protocol, and used in practice in many different operational network contexts. Such algorithms inherit much of the properties of congestion controllers implementing one of the possible combination of AQM/ECN schemes at nodes and flow control at sources. In this paper we propose a linear program formulation of the multi-commodity flow problem with congestion control, under max-min fairness, comprising demands with or without exogenous peak rates. Our evaluations of the gain, using path diversity, in scenarios as intra-domain traffic engineering and wireless mesh networks encourages real implementations, especially in presence of hot spots demands and non uniform traffic matrices. We propose a flow aware perspective of the subject by using a natural multi-path extension to current congestion controllers and show its performance with respect to current proposa...

  16. Coordination, Organisation and Model-driven Approaches for Dynamic, Flexible, Robust Software and Services Engineering

    Science.gov (United States)

    Nieves, Juan Carlos; Padget, Julian; Vasconcelos, Wamberto; Staikopoulos, Athanasios; Cliffe, Owen; Dignum, Frank; Vázquez-Salceda, Javier; Clarke, Siobhán; Reed, Chris

    Enterprise systems are increasingly composed of (and even functioning as) components in a dynamic, digital ecosystem. On the one hand, this new situation requires flexible, spontaneous and opportunistic collaboration activities to be identified and established among (electronic) business parties. On the other, it demands engineering methods that are able to integrate new functionalities and behaviours into running systems composed by active, distributed, interdependent processes. Here we present a multi-level architecture that combines organisational and coordination theories with model driven development, for the implementation, deployment and management of dynamic, flexible and robust service-oriented business applications, combined with a service layer that accommodates semantic service description, fine-grained semantic service discovery and the dynamic adaptation of services to meet changing circumstances.

  17. Vascular tissue engineering of small-diameter blood vessels: reviewing the electrospinning approach.

    Science.gov (United States)

    Ercolani, Enrico; Del Gaudio, Costantino; Bianco, Alessandra

    2015-08-01

    Vascular tissue engineering is a relevant research field aimed at elaborating and proposing innovative solutions to overcome the drawbacks related to the use of conventional blood vessel substitutes, especially referring to small-diameter grafts. For this aim, electrospinning can be regarded as a valuable technique to produce novel scaffolds with several functional characteristics that can be usefully tailored for the application discussed here. The reproduction of the natural extracellular matrix obtained by processing bioresorbable polymers, either functionalized or not, is driving the biomedical research towards technical solutions that can lead to an actual therapeutic improvement. In this context, this paper reviews those studies focused on the selection of suitable biomaterials for vascular applications, their microstructure, the cell response to polymeric fibres and the strategies considered so far to modify and therefore enhance the performance of final electrospun scaffolds.

  18. Orthographic Software Modelling: A Novel Approach to View-Based Software Engineering

    Science.gov (United States)

    Atkinson, Colin

    The need to support multiple views of complex software architectures, each capturing a different aspect of the system under development, has been recognized for a long time. Even the very first object-oriented analysis/design methods such as the Booch method and OMT supported a number of different diagram types (e.g. structural, behavioral, operational) and subsequent methods such as Fusion, Kruchten's 4+1 views and the Rational Unified Process (RUP) have added many more views over time. Today's leading modeling languages such as the UML and SysML, are also oriented towards supporting different views (i.e. diagram types) each able to portray a different facets of a system's architecture. More recently, so called enterprise architecture frameworks such as the Zachman Framework, TOGAF and RM-ODP have become popular. These add a whole set of new non-functional views to the views typically emphasized in traditional software engineering environments.

  19. A comprehensive training approach for biomedical engineers in biochemistry and in vitro diagnostics technology.

    Science.gov (United States)

    Spyropoulos, Basile; Tzavaras, Aris

    2007-01-01

    The purpose of this paper is to review 20 years (1987-2007) of experience in training young Biomedical Engineers in Biochemistry and in vitro Diagnostics (IVD) Technology. This encountering has resulted in the gradual formation of a comprehensive training package that includes lectures and laboratory practicals, supported by both, traditional and on-line digital means, such as lecture-notes, slides, videos, demos and equipment simulations. Further, this course is maintained up to date by several research and development activities that offer partially feed back to the course and enrich its contents with custom developed devices, methods and application software. In this paper are presented, first, the structure and the components of this course, and second, the most important custom developed novelties, which have been integrated in the IVD Technology laboratory-practicals.

  20. The system approach to energy savings in engineering networks of buildings

    Directory of Open Access Journals (Sweden)

    L.L. Goshka

    2011-01-01

    Full Text Available Taking into consideration that there is not definite differentiation between definitions "economy of energy" and "energy saving", often the effect of energy effective technologies can be received only by reduction of air exchange, that is breach of sanitary and hygienic regulations. In the article the attempt to distinguish these definitions with using system approach is done. In building branch absence of the system approach to building and city leads to serious system errors. For example, warming of building wallings using natural ventilation don't give real energy saving, but it leads to the air exchange decrease, therefore the given action raises risk of various diseases. In the article various system errors which can lead to acceptance of the erroneous decisions, influencing the sensitive initial data through air exchange reduction, are considered. A consequence of it are diseases of noninfectious character. To decrease quantity of system errors it is offered to use the system approach to these problems.