WorldWideScience

Sample records for models based engineering

  1. Principles of models based engineering

    Energy Technology Data Exchange (ETDEWEB)

    Dolin, R.M.; Hefele, J.

    1996-11-01

    This report describes a Models Based Engineering (MBE) philosophy and implementation strategy that has been developed at Los Alamos National Laboratory`s Center for Advanced Engineering Technology. A major theme in this discussion is that models based engineering is an information management technology enabling the development of information driven engineering. Unlike other information management technologies, models based engineering encompasses the breadth of engineering information, from design intent through product definition to consumer application.

  2. Model-based Software Engineering

    DEFF Research Database (Denmark)

    Kindler, Ekkart

    2010-01-01

    The vision of model-based software engineering is to make models the main focus of software development and to automatically generate software from these models. Part of that idea works already today. But, there are still difficulties when it comes to behaviour. Actually, there is no lack in models...

  3. Model based development of engine control algorithms

    NARCIS (Netherlands)

    Dekker, H.J.; Sturm, W.L.

    1996-01-01

    Model based development of engine control systems has several advantages. The development time and costs are strongly reduced because much of the development and optimization work is carried out by simulating both engine and control system. After optimizing the control algorithm it can be executed

  4. Model-Based Systems Engineering in Concurrent Engineering Centers

    Science.gov (United States)

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

    2015-01-01

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

  5. Mars 2020 Model Based Systems Engineering Pilot

    Science.gov (United States)

    Dukes, Alexandra Marie

    2017-01-01

    The pilot study is led by the Integration Engineering group in NASA's Launch Services Program (LSP). The Integration Engineering (IE) group is responsible for managing the interfaces between the spacecraft and launch vehicle. This pilot investigates the utility of Model-Based Systems Engineering (MBSE) with respect to managing and verifying interface requirements. The main objectives of the pilot are to model several key aspects of the Mars 2020 integrated operations and interface requirements based on the design and verification artifacts from Mars Science Laboratory (MSL) and to demonstrate how MBSE could be used by LSP to gain further insight on the interface between the spacecraft and launch vehicle as well as to enhance how LSP manages the launch service. The method used to accomplish this pilot started through familiarization of SysML, MagicDraw, and the Mars 2020 and MSL systems through books, tutorials, and NASA documentation. MSL was chosen as the focus of the model since its processes and verifications translate easily to the Mars 2020 mission. The study was further focused by modeling specialized systems and processes within MSL in order to demonstrate the utility of MBSE for the rest of the mission. The systems chosen were the In-Flight Disconnect (IFD) system and the Mass Properties process. The IFD was chosen as a system of focus since it is an interface between the spacecraft and launch vehicle which can demonstrate the usefulness of MBSE from a system perspective. The Mass Properties process was chosen as a process of focus since the verifications for mass properties occur throughout the lifecycle and can demonstrate the usefulness of MBSE from a multi-discipline perspective. Several iterations of both perspectives have been modeled and evaluated. While the pilot study will continue for another 2 weeks, pros and cons of using MBSE for LSP IE have been identified. A pro of using MBSE includes an integrated view of the disciplines, requirements, and

  6. Graph-based modelling in engineering

    CERN Document Server

    Rysiński, Jacek

    2017-01-01

    This book presents versatile, modern and creative applications of graph theory in mechanical engineering, robotics and computer networks. Topics related to mechanical engineering include e.g. machine and mechanism science, mechatronics, robotics, gearing and transmissions, design theory and production processes. The graphs treated are simple graphs, weighted and mixed graphs, bond graphs, Petri nets, logical trees etc. The authors represent several countries in Europe and America, and their contributions show how different, elegant, useful and fruitful the utilization of graphs in modelling of engineering systems can be. .

  7. Implementing model based systems engineering in South Africa

    CSIR Research Space (South Africa)

    Oosthuizen, Rudolph

    2017-10-01

    Full Text Available and validation activities beginning in the conceptual design phase and continuing throughout development and later life cycle phases”. Model-Based Systems Engineering (MBSE) employs modelling languages, such as Systems Modelling Language (SysML) or Unified...). Model Based Systems Engineering General Concepts MBSE is defined as the formalized application of modeling to support system requirements, design, analysis, verification and validation activities throughout the system life cycle phases (Gau...

  8. A quantum heat engine based on Tavis-Cummings model

    Science.gov (United States)

    Sun, Kai-Wei; Li, Ran; Zhang, Guo-Feng

    2017-09-01

    This paper will investigate a four-stroke quantum heat engine based on the Tavis-Cummings model. The cycle of the heat engine is similar to the Otto cycle in classical thermodynamics. The relationship between output power as well as cycle efficiency and external physical system parameters are given. Under this condition, the entanglement behavior of the system will be studied. The system can show considerable entanglement by strictly controlling relevant parameters. Unlike common two-level quantum heat engines, efficiency is a function of temperature, showing interesting and unexpected phenomena. Several ways to adjust engine properties by external parameters are proposed, with which the output power and efficiency can be optimized. The heat engine model exhibits high efficiency and output power with the participation of a small number of photons, and decay rapidly as the number of photons increases in entangled area but shows interesting behaviors in non-entangled area of photon numbers.

  9. Applying Model Based Systems Engineering to NASA's Space Communications Networks

    Science.gov (United States)

    Bhasin, Kul; Barnes, Patrick; Reinert, Jessica; Golden, Bert

    2013-01-01

    System engineering practices for complex systems and networks now require that requirement, architecture, and concept of operations product development teams, simultaneously harmonize their activities to provide timely, useful and cost-effective products. When dealing with complex systems of systems, traditional systems engineering methodology quickly falls short of achieving project objectives. This approach is encumbered by the use of a number of disparate hardware and software tools, spreadsheets and documents to grasp the concept of the network design and operation. In case of NASA's space communication networks, since the networks are geographically distributed, and so are its subject matter experts, the team is challenged to create a common language and tools to produce its products. Using Model Based Systems Engineering methods and tools allows for a unified representation of the system in a model that enables a highly related level of detail. To date, Program System Engineering (PSE) team has been able to model each network from their top-level operational activities and system functions down to the atomic level through relational modeling decomposition. These models allow for a better understanding of the relationships between NASA's stakeholders, internal organizations, and impacts to all related entities due to integration and sustainment of existing systems. Understanding the existing systems is essential to accurate and detailed study of integration options being considered. In this paper, we identify the challenges the PSE team faced in its quest to unify complex legacy space communications networks and their operational processes. We describe the initial approaches undertaken and the evolution toward model based system engineering applied to produce Space Communication and Navigation (SCaN) PSE products. We will demonstrate the practice of Model Based System Engineering applied to integrating space communication networks and the summary of its

  10. Fusing Quantitative Requirements Analysis with Model-based Systems Engineering

    Science.gov (United States)

    Cornford, Steven L.; Feather, Martin S.; Heron, Vance A.; Jenkins, J. Steven

    2006-01-01

    A vision is presented for fusing quantitative requirements analysis with model-based systems engineering. This vision draws upon and combines emergent themes in the engineering milieu. "Requirements engineering" provides means to explicitly represent requirements (both functional and non-functional) as constraints and preferences on acceptable solutions, and emphasizes early-lifecycle review, analysis and verification of design and development plans. "Design by shopping" emphasizes revealing the space of options available from which to choose (without presuming that all selection criteria have previously been elicited), and provides means to make understandable the range of choices and their ramifications. "Model-based engineering" emphasizes the goal of utilizing a formal representation of all aspects of system design, from development through operations, and provides powerful tool suites that support the practical application of these principles. A first step prototype towards this vision is described, embodying the key capabilities. Illustrations, implications, further challenges and opportunities are outlined.

  11. Enhanced Engine Performance During Emergency Operation Using a Model-Based Engine Control Architecture

    Science.gov (United States)

    Csank, Jeffrey T.; Connolly, Joseph W.

    2016-01-01

    This paper discusses the design and application of model-based engine control (MBEC) for use during emergency operation of the aircraft. The MBEC methodology is applied to the Commercial Modular Aero-Propulsion System Simulation 40k (CMAPSS40k) and features an optimal tuner Kalman Filter (OTKF) to estimate unmeasured engine parameters, which can then be used for control. During an emergency scenario, normally-conservative engine operating limits may be relaxed to increase the performance of the engine and overall survivability of the aircraft; this comes at the cost of additional risk of an engine failure. The MBEC architecture offers the advantage of estimating key engine parameters that are not directly measureable. Estimating the unknown parameters allows for tighter control over these parameters, and on the level of risk the engine will operate at. This will allow the engine to achieve better performance than possible when operating to more conservative limits on a related, measurable parameter.

  12. Model-Based Engineering for Supply Chain Risk Management

    Science.gov (United States)

    2015-09-30

    General Accounting Office has placed ICT Supply Chain Risk Management on its annual “Key Issues, High Risk” list [9]. A primary contributor to...Model-Based Engineering for Supply Chain Risk Management Dan Shoemaker, Ph.D. University of Detroit Mercy Carol Woody, Ph.D. Carnegie Mellon...Design Language (AADL), which has tools for modeling and compliance verification, provides an effective capability to model and describe all component

  13. Product Lifecycle Management Architecture: A Model Based Systems Engineering Analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Noonan, Nicholas James [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-07-01

    This report is an analysis of the Product Lifecycle Management (PLM) program. The analysis is centered on a need statement generated by a Nuclear Weapons (NW) customer. The need statement captured in this report creates an opportunity for the PLM to provide a robust service as a solution. Lifecycles for both the NW and PLM are analyzed using Model Based System Engineering (MBSE).

  14. Mechanics and model-based control of advanced engineering systems

    CERN Document Server

    Irschik, Hans; Krommer, Michael

    2014-01-01

    Mechanics and Model-Based Control of Advanced Engineering Systems collects 32 contributions presented at the International Workshop on Advanced Dynamics and Model Based Control of Structures and Machines, which took place in St. Petersburg, Russia in July 2012. The workshop continued a series of international workshops, which started with a Japan-Austria Joint Workshop on Mechanics and Model Based Control of Smart Materials and Structures and a Russia-Austria Joint Workshop on Advanced Dynamics and Model Based Control of Structures and Machines. In the present volume, 10 full-length papers based on presentations from Russia, 9 from Austria, 8 from Japan, 3 from Italy, one from Germany and one from Taiwan are included, which represent the state of the art in the field of mechanics and model based control, with particular emphasis on the application of advanced structures and machines.

  15. Building a Narrative Based Requirements Engineering Mediation Model

    Science.gov (United States)

    Ma, Nan; Hall, Tracy; Barker, Trevor

    This paper presents a narrative-based Requirements Engineering (RE) mediation model to help RE practitioners to effectively identify, define, and resolve conflicts of interest, goals, and requirements. Within the SPI community, there is a common belief that social, human, and organizational issues significantly impact on the effectiveness of software process improvement in general and the requirements engineering process in particularl. Conflicts among different stakeholders are an important human and social issue that need more research attention in the SPI and RE community. By drawing on the conflict resolution literature and IS literature, we argue that conflict resolution in RE is a mediated process, in which a requirements engineer can act as a mediator among different stakeholders. To address socio-psychological aspects of conflict in RE and SPI, Winslade and Monk (2000)'s narrative mediation model is introduced, justified, and translated into the context of RE.

  16. Test-Driven, Model-Based Systems Engineering

    DEFF Research Database (Denmark)

    Munck, Allan

    Hearing systems have evolved over many years from simple mechanical devices (horns) to electronic units consisting of microphones, amplifiers, analog filters, loudspeakers, batteries, etc. Digital signal processors replaced analog filters to provide better performance end new features. Central....... This thesis concerns methods for identifying, selecting and implementing tools for various aspects of model-based systems engineering. A comprehensive method was proposed that include several novel steps such as techniques for analyzing the gap between requirements and tool capabilities. The method...... was verified with good results in two case studies for selection of a traceability tool (single-tool scenario) and a set of modeling tools (multi-tool scenarios). Models must be subjected to testing to allow engineers to predict functionality and performance of systems. Test-first strategies are known...

  17. Model-based engineering for medical-device software.

    Science.gov (United States)

    Ray, Arnab; Jetley, Raoul; Jones, Paul L; Zhang, Yi

    2010-01-01

    This paper demonstrates the benefits of adopting model-based design techniques for engineering medical device software. By using a patient-controlled analgesic (PCA) infusion pump as a candidate medical device, the authors show how using models to capture design information allows for i) fast and efficient construction of executable device prototypes ii) creation of a standard, reusable baseline software architecture for a particular device family, iii) formal verification of the design against safety requirements, and iv) creation of a safety framework that reduces verification costs for future versions of the device software. 1.

  18. Model based document and report generation for systems engineering

    Science.gov (United States)

    Delp, C.; Lam, D.; Fosse, E.; Lee, Cin-Young

    As Model Based Systems Engineering (MBSE) practices gain adoption, various approaches have been developed in order to simplify and automate the process of generating documents from models. Essentially, all of these techniques can be unified around the concept of producing different views of the model according to the needs of the intended audience. In this paper, we will describe a technique developed at JPL of applying SysML Viewpoints and Views to generate documents and reports. An architecture of model-based view and document generation will be presented, and the necessary extensions to SysML with associated rationale will be explained. A survey of examples will highlight a variety of views that can be generated, and will provide some insight into how collaboration and integration is enabled. We will also describe the basic architecture for the enterprise applications that support this approach.

  19. Model Based Document and Report Generation for Systems Engineering

    Science.gov (United States)

    Delp, Christopher; Lam, Doris; Fosse, Elyse; Lee, Cin-Young

    2013-01-01

    As Model Based Systems Engineering (MBSE) practices gain adoption, various approaches have been developed in order to simplify and automate the process of generating documents from models. Essentially, all of these techniques can be unified around the concept of producing different views of the model according to the needs of the intended audience. In this paper, we will describe a technique developed at JPL of applying SysML Viewpoints and Views to generate documents and reports. An architecture of model-based view and document generation will be presented, and the necessary extensions to SysML with associated rationale will be explained. A survey of examples will highlight a variety of views that can be generated, and will provide some insight into how collaboration and integration is enabled. We will also describe the basic architecture for the enterprise applications that support this approach.

  20. Combustion engine diagnosis model-based condition monitoring of gasoline and diesel engines and their components

    CERN Document Server

    Isermann, Rolf

    2017-01-01

    This book offers first a short introduction to advanced supervision, fault detection and diagnosis methods. It then describes model-based methods of fault detection and diagnosis for the main components of gasoline and diesel engines, such as the intake system, fuel supply, fuel injection, combustion process, turbocharger, exhaust system and exhaust gas aftertreatment. Additionally, model-based fault diagnosis of electrical motors, electric, pneumatic and hydraulic actuators and fault-tolerant systems is treated. In general series production sensors are used. It includes abundant experimental results showing the detection and diagnosis quality of implemented faults. Written for automotive engineers in practice, it is also of interest to graduate students of mechanical and electrical engineering and computer science. The Content Introduction.- I SUPERVISION, FAULT DETECTION AND DIAGNOSIS METHODS.- Supervision, Fault-Detection and Fault-Diagnosis Methods - a short Introduction.- II DIAGNOSIS OF INTERNAL COMBUST...

  1. Model based methods and tools for process systems engineering

    DEFF Research Database (Denmark)

    Gani, Rafiqul

    Process systems engineering (PSE) provides means to solve a wide range of problems in a systematic and efficient manner. This presentation will give a perspective on model based methods and tools needed to solve a wide range of problems in product-process synthesis-design. These methods and tools...... need to be integrated with work-flows and data-flows for specific product-process synthesis-design problems within a computer-aided framework. The framework therefore should be able to manage knowledge-data, models and the associated methods and tools needed by specific synthesis-design work...... of model based methods and tools within a computer aided framework for product-process synthesis-design will be highlighted....

  2. Model-based engineering for laser weapons systems

    Science.gov (United States)

    Panthaki, Malcolm; Coy, Steve

    2011-10-01

    The Comet Performance Engineering Workspace is an environment that enables integrated, multidisciplinary modeling and design/simulation process automation. One of the many multi-disciplinary applications of the Comet Workspace is for the integrated Structural, Thermal, Optical Performance (STOP) analysis of complex, multi-disciplinary space systems containing Electro-Optical (EO) sensors such as those which are designed and developed by and for NASA and the Department of Defense. The CometTM software is currently able to integrate performance simulation data and processes from a wide range of 3-D CAD and analysis software programs including CODE VTM from Optical Research Associates and SigFitTM from Sigmadyne Inc. which are used to simulate the optics performance of EO sensor systems in space-borne applications. Over the past year, Comet Solutions has been working with MZA Associates of Albuquerque, NM, under a contract with the Air Force Research Laboratories. This funded effort is a "risk reduction effort", to help determine whether the combination of Comet and WaveTrainTM, a wave optics systems engineering analysis environment developed and maintained by MZA Associates and used by the Air Force Research Laboratory, will result in an effective Model-Based Engineering (MBE) environment for the analysis and design of laser weapons systems. This paper will review the results of this effort and future steps.

  3. Model-Based Engineering and Manufacturing CAD/CAM Benchmark

    International Nuclear Information System (INIS)

    Domm, T.D.; Underwood, R.S.

    1999-01-01

    The Benehmark Project was created from a desire to identify best practices and improve the overall efficiency and performance of the Y-12 Plant's systems and personnel supporting the manufacturing mission. The mission of the benchmark team was to search out industry leaders in manufacturing and evaluate their engineering practices and processes to determine direction and focus fm Y-12 modmizadon efforts. The companies visited included several large established companies and anew, small, high-tech machining firm. As a result of this effort changes are recommended that will enable Y-12 to become a more responsive cost-effective manufacturing facility capable of suppording the needs of the Nuclear Weapons Complex (NW at sign) and Work Fw Others into the 21' century. The benchmark team identified key areas of interest, both focused and gencml. The focus arm included Human Resources, Information Management, Manufacturing Software Tools, and Standarda/ Policies and Practices. Areas of general interest included Inhstructure, Computer Platforms and Networking, and Organizational Structure. The method for obtaining the desired information in these areas centered on the creation of a benchmark questionnaire. The questionnaire was used throughout each of the visits as the basis for information gathering. The results of this benchmark showed that all companies are moving in the direction of model-based engineering and manufacturing. There was evidence that many companies are trying to grasp how to manage current and legacy data. In terms of engineering design software tools, the companies contacted were using both 3-D solid modeling and surfaced Wire-frame models. The manufacturing computer tools were varie4 with most companies using more than one software product to generate machining data and none currently performing model-based manufacturing (MBM) ftom a common medel. The majority of companies were closer to identifying or using a single computer-aided design (CAD) system

  4. 3D modeling based on CityEngine

    Science.gov (United States)

    Jia, Guangyin; Liao, Kaiju

    2017-03-01

    Currently, there are many 3D modeling softwares, like 3DMAX, AUTOCAD, and more populous BIM softwares represented by REVIT. CityEngine modeling software introduced in this paper can fully utilize the existing GIS data and combine other built models to make 3D modeling on internal and external part of buildings in a rapid and batch manner, so as to improve the 3D modeling efficiency.

  5. Software-engineering-based model for mitigating Repetitive Strain ...

    African Journals Online (AJOL)

    The incorporation of Information and Communication Technology (ICT) in virtually all facets of human endeavours has fostered the use of computers. This has induced Repetitive Stress Injury (RSI) for continuous and persistent computer users. Proposing a software engineering model capable of enacted RSI force break ...

  6. Model Based Systems Engineering on the Europa Mission Concept Study

    Science.gov (United States)

    Bayer, Todd J.; Chung, Seung; Cole, Bjorn; Cooke, Brian; Dekens, Frank; Delp, Chris; Gontijo, I.; Lewis, Kari; Moshir, Mehrdad; Rasmussen, Robert; hide

    2012-01-01

    At the start of 2011, the proposed Jupiter Europa Orbiter (JEO) mission was staffing up in expectation of becoming an official project later in the year for a launch in 2020. A unique aspect of the pre-project work was a strong emphasis and investment on the foundations of Model-Based Systems Engineering (MBSE). As so often happens in this business, plans changed: NASA's budget and science priorities were released and together fundamentally changed the course of JEO. As a result, it returned to being a study task whose objective is to propose more affordable ways to accomplish the science. As part of this transition, the question arose as to whether it could continue to afford the investment in MBSE. In short, the MBSE infusion has survived and is providing clear value to the study effort. By leveraging the existing infrastructure and a modest additional investment, striking advances in the capture and analysis of designs using MBSE were achieved. In the process, the need to remain relevant in the new environment has brought about a wave of innovation and progress. The effort has reaffirmed the importance of architecting. It has successfully harnessed the synergistic relationship of architecting to system modeling. We have found that MBSE can provide greater agility than traditional methods. We have also found that a diverse 'ecosystem' of modeling tools and languages (SysML, Mathematica, even Excel) is not only viable, but an important enabler of agility and adaptability. This paper will describe the successful application of MBSE in the dynamic environment of early mission formulation, the significant results produced and lessons learned in the process.

  7. Femur Model Reconstruction Based on Reverse Engineering and Rapid Prototyping

    Science.gov (United States)

    Tang, Tongming; Zhang, Zheng; Ni, Hongjun; Deng, Jiawen; Huang, Mingyu

    Precise reconstruction of 3D models is fundamental and crucial to the researches of human femur. In this paper we present our approach towards tackling this problem. The surface of a human femur was scanned using a hand-held 3D laser scanner. The data obtained, in the form of point cloud, was then processed using the reverse engineering software Geomagic and the CAD/CAM software CimatronE to reconstruct a digital 3D model. The digital model was then used by the rapid prototyping machine to build a physical model of human femur using 3D printing. The geometric characteristics of the obtained physical model matched that of the original femur. The process of "physical object - 3D data - digital 3D model - physical model" presented in this paper provides a foundation of precise modeling for the digital manufacturing, virtual assembly, stress analysis, and simulated surgery of artificial bionic femurs.

  8. Optimization of Component Based Software Engineering Model Using Neural Network

    OpenAIRE

    Gaurav Kumar; Pradeep Kumar Bhatia

    2014-01-01

    The goal of Component Based Software Engineering (CBSE) is to deliver high quality, more reliable and more maintainable software systems in a shorter time and within limited budget by reusing and combining existing quality components. A high quality system can be achieved by using quality components, framework and integration process that plays a significant role. So, techniques and methods used for quality assurance and assessment of a component based system is different from those of the tr...

  9. Seamless Method- and Model-based Software and Systems Engineering

    Science.gov (United States)

    Broy, Manfred

    Today engineering software intensive systems is still more or less handicraft or at most at the level of manufacturing. Many steps are done ad-hoc and not in a fully systematic way. Applied methods, if any, are not scientifically justified, not justified by empirical data and as a result carrying out large software projects still is an adventure. However, there is no reason why the development of software intensive systems cannot be done in the future with the same precision and scientific rigor as in established engineering disciplines. To do that, however, a number of scientific and engineering challenges have to be mastered. The first one aims at a deep understanding of the essentials of carrying out such projects, which includes appropriate models and effective management methods. What is needed is a portfolio of models and methods coming together with a comprehensive support by tools as well as deep insights into the obstacles of developing software intensive systems and a portfolio of established and proven techniques and methods with clear profiles and rules that indicate when which method is ready for application. In the following we argue that there is scientific evidence and enough research results so far to be confident that solid engineering of software intensive systems can be achieved in the future. However, yet quite a number of scientific research problems have to be solved.

  10. Integration of supervisory control synthesis in model-based systems engineering

    NARCIS (Netherlands)

    J.C.M. Baeten (Jos); J.M. van de Mortel-Fronczak (Joanna); J.E. Rooda (Jacobus)

    2011-01-01

    htmlabstractDue to increasing system complexity, time-to-market and development costs reduction, there are higher demands on engineering processes. Model-based engineering processes can play a role here because they support system development by enabling the use of various model-based analysis

  11. Modeling of Engine Parameters for Condition-Based Maintenance of the MTU Series 2000 Diesel Engine

    Science.gov (United States)

    2016-09-01

    temperature and combined B exhaust temperature. Combined A exhaust temperature measures exhaust gas temperature of cylinders located on the left side of the...engine, and combined B exhaust temperature measures exhaust gas temperature of cylinders on the right side of the engine. For our analysis, the...exhaust gas temperature. 59 V. CONCLUSION AND FUTURE WORK Condition-based maintenance (CBM) is a preventive maintenance method that predicts the onset

  12. Recognition of Aircraft Engine Sound Based on GMM-UBM Model

    Directory of Open Access Journals (Sweden)

    Yuan Shuai

    2017-01-01

    Full Text Available Gaussian mixture model-universal background model (GMM-UBM is a commonly-used speaker recognition technology, and which has achieved good effect for detection speaker’s sound. In this paper, we explore GMM-UBM method for use with abnormal aircraft engine sound detection. We designed a GMM-UBM based aircraft engine sound recognition system, which extracts MFCC feature parameters and trains the GMM-UBM models using maximum a posteriori (MAP adaptive algorithm. Experimental results show the GMM-UBM based aircraft engine sound recognition system can achieve higher recognize rate in real-word aircraft engine sound test.

  13. Integration of supervisory control synthesis in model-based systems engineering

    NARCIS (Netherlands)

    J.C.M. Baeten (Jos); J.M. van de Mortel-Fronczak (Joanna); J.E. Rooda (Jacobus)

    2016-01-01

    htmlabstractIncreasing system complexity, time to market and development costs reduction place higher demands on engineering processes. Formal models play an important role here because they enable the use of various model-based analyses and early integration techniques and tools. Engineering

  14. State of the Art : Integrated Management of Requirements in Model-Based Software Engineering

    OpenAIRE

    Thörn, Christer

    2006-01-01

    This report describes the background and future of research concerning integrated management of requirements in model-based software engineering. The focus is on describing the relevant topics and existing theoretical backgrounds that form the basis for the research. The report describes the fundamental difficulties of requirements engineering for software projects, and proposes that the results and methods of models in software engineering can help leverage those problems. Taking inspiration...

  15. Electric Power Engineer Fostering Program based on a New Conceptual Model of Engineers' Ability

    Science.gov (United States)

    Amano, Minoru; Katabami, Tsutomu; Yokosawa, Hiroyuki; Akamine, Yotaro

    We made a new fostering program for electric power engineer aiming to win market and to reduce management risk. The program is based on the best learning method of three skills of Robert L Katz (1)----expansion of human skill and conceptual skill put together at expansion speed of technical skill---- from four study verification results. This method is applied to the electric power engineer, and confirmed by Kirkpatrick level II.(2) It is thought that the above-mentioned two problems can be cleared by achieving the result which will correspond to level III and IV in the near future.

  16. Model-Based Fault Management Engineering Tool Suite, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's successful development of next generation space vehicles, habitats, and robotic systems will rely on effective Fault Management Engineering. Our proposed...

  17. Model-Based Fault Management Engineering Tool Suite, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's successful development of next generation space vehicles, habitats, and robotic systems will rely on effective Fault Management Engineering. Our proposed...

  18. Rate-Based Model Predictive Control of Turbofan Engine Clearance

    Science.gov (United States)

    DeCastro, Jonathan A.

    2006-01-01

    An innovative model predictive control strategy is developed for control of nonlinear aircraft propulsion systems and sub-systems. At the heart of the controller is a rate-based linear parameter-varying model that propagates the state derivatives across the prediction horizon, extending prediction fidelity to transient regimes where conventional models begin to lose validity. The new control law is applied to a demanding active clearance control application, where the objectives are to tightly regulate blade tip clearances and also anticipate and avoid detrimental blade-shroud rub occurrences by optimally maintaining a predefined minimum clearance. Simulation results verify that the rate-based controller is capable of satisfying the objectives during realistic flight scenarios where both a conventional Jacobian-based model predictive control law and an unconstrained linear-quadratic optimal controller are incapable of doing so. The controller is evaluated using a variety of different actuators, illustrating the efficacy and versatility of the control approach. It is concluded that the new strategy has promise for this and other nonlinear aerospace applications that place high importance on the attainment of control objectives during transient regimes.

  19. An Open-Source Simulation Environment for Model-Based Engineering, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed work is a new spacecraft simulation environment for model-based engineering of flight algorithms and software. The goal is to provide a much faster way...

  20. A Physics-Based Starting Model for Gas Turbine Engines, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this proposal is to demonstrate the feasibility of producing an integrated starting model for gas turbine engines using a new physics-based...

  1. Model-Based Fault Diagnosis for Turboshaft Engines

    National Research Council Canada - National Science Library

    Green, Michael

    1998-01-01

    Tests are described which, when used to augment the existing periodic maintenance and pre-flight checks of T700 engines, can greatly improve the chances of uncovering a problem compared to the current practice...

  2. Reliability Estimation of Aero-engine Based on Mixed Weibull Distribution Model

    Science.gov (United States)

    Yuan, Zhongda; Deng, Junxiang; Wang, Dawei

    2018-02-01

    Aero-engine is a complex mechanical electronic system, based on analysis of reliability of mechanical electronic system, Weibull distribution model has an irreplaceable role. Till now, only two-parameter Weibull distribution model and three-parameter Weibull distribution are widely used. Due to diversity of engine failure modes, there is a big error with single Weibull distribution model. By contrast, a variety of engine failure modes can be taken into account with mixed Weibull distribution model, so it is a good statistical analysis model. Except the concept of dynamic weight coefficient, in order to make reliability estimation result more accurately, three-parameter correlation coefficient optimization method is applied to enhance Weibull distribution model, thus precision of mixed distribution reliability model is improved greatly. All of these are advantageous to popularize Weibull distribution model in engineering applications.

  3. A Software Technology Transition Entropy Based Engineering Model

    Science.gov (United States)

    2002-03-01

    D., The Double Helix, A Personal Account of the Discovery of the Structure of DNA , Simon and Schuster, New York, 1968. (Wehrl 1978) Wehrl, Alfred...Basili, Victor R., and Musa , John D., “The Future Engineering of Software: A Management Perspective,” Computer, pp. 90-96, September 1991. (Basili...calculations required. The tables and data were extracted from a supporting document (Behnke 2001) which describes the calculations. This represents

  4. Focus on connections for successful organizational transformation to model based engineering

    Science.gov (United States)

    Babineau, Guy L.

    2015-05-01

    Organizational Transformation to a Model Based Engineering Culture is a significant goal for Northrop Grumman Electronic Systems in order to achieve objectives of increased engineering performance. While organizational change is difficult, a focus on connections is creating success. Connections include model to model, program phase to program phase and organization to organization all through Model Based techniques. This presentation will address the techniques employed by Northrop Grumman to achieve these results as well as address continued focus and efforts. Model to model connections are very effective in automating implicit linkages between models for the purpose of ensuring consistency across a set of models and also for rapidly assessing impact of change. Program phase to phase connections are very important for reducing development time as well as reducing potential errors in moving from one program phase to another. Organization to organization communication is greatly facilitated using model based techniques to eliminate ambiguity and drive consistency and reuse.

  5. The Validation of Computer-based Models in Engineering: Some Lessons from Computing Science

    Directory of Open Access Journals (Sweden)

    D. J. Murray-Smith

    2001-01-01

    Full Text Available Questions of the quality of computer-based models and the formal processes of model testing, involving internal verification and external validation, are usually given only passing attention in engineering reports and in technical publications. However, such models frequently provide a basis for analysis methods, design calculations or real-time decision-making in complex engineering systems. This paper reviews techniques used for external validation of computer-based models and contrasts the somewhat casual approach which is usually adopted in this field with the more formal approaches to software testing and documentation recommended for large software projects. Both activities require intimate knowledge of the intended application, a systematic approach and considerable expertise and ingenuity in the design of tests. It is concluded that engineering degree courses dealing with modelling techniques and computer simulation should put more emphasis on model limitations, testing and validation.

  6. Model-based Acceleration Control of Turbofan Engines with a Hammerstein-Wiener Representation

    Science.gov (United States)

    Wang, Jiqiang; Ye, Zhifeng; Hu, Zhongzhi; Wu, Xin; Dimirovsky, Georgi; Yue, Hong

    2017-05-01

    Acceleration control of turbofan engines is conventionally designed through either schedule-based or acceleration-based approach. With the widespread acceptance of model-based design in aviation industry, it becomes necessary to investigate the issues associated with model-based design for acceleration control. In this paper, the challenges for implementing model-based acceleration control are explained; a novel Hammerstein-Wiener representation of engine models is introduced; based on the Hammerstein-Wiener model, a nonlinear generalized minimum variance type of optimal control law is derived; the feature of the proposed approach is that it does not require the inversion operation that usually upsets those nonlinear control techniques. The effectiveness of the proposed control design method is validated through a detailed numerical study.

  7. Development Of Entrepreneur Learning Model Based On Problem Based Learning To Increase Competency Independence And Creativity Students Of Industrial Engineering

    Directory of Open Access Journals (Sweden)

    Leola Dewiyani

    2017-10-01

    Full Text Available Currently it is undeniable that the competition to get a job is very tight and of course universities have an important role in printing human resources that can compete globally not least with the Department of Industrial Engineering Faculty of Engineering Muhammadiyah University of Jakarta FT UMJ. Problems that occur is based on the analysis obtained from the track record of graduates researchers found that 60 percent of students of Industrial Engineering FT UMJ work not in accordance with the level of education owned so financially their income is still below the standard. This study aims to improve the competence of students of Industrial Engineering Department FT UMJ in entrepreneurship courses especially through the development of Problem Based Learning based learning model. Specific targets of this research were conducted with the aim to identify and analyze the need to implement learning model based on Problem Based Learning Entrepreneurship and to design and develop the model of entrepreneurship based on Problem Based Learning to improve the competence independence and creativity of Industrial Engineering students of FT UMJ in Entrepreneurship course. To achieve the above objectives this research uses research and development R amp D method. The product produced in this research is the detail of learning model of entrepreneurial model based on Problem Based Learning entrepreneurship model based on Problem Based Learning and international journals

  8. 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.

  9. Model-Based Engineering Design for Trade Space Exploration throughout the Design Cycle

    Science.gov (United States)

    Lamassoure, Elisabeth S.; Wall, Stephen D.; Easter, Robert W.

    2004-01-01

    This paper presents ongoing work to standardize model-based system engineering as a complement to point design development in the conceptual design phase of deep space missions. It summarizes two first steps towards practical application of this capability within the framework of concurrent engineering design teams and their customers. The first step is standard generation of system sensitivities models as the output of concurrent engineering design sessions, representing the local trade space around a point design. A review of the chosen model development process, and the results of three case study examples, demonstrate that a simple update to the concurrent engineering design process can easily capture sensitivities to key requirements. It can serve as a valuable tool to analyze design drivers and uncover breakpoints in the design. The second step is development of rough-order- of-magnitude, broad-range-of-validity design models for rapid exploration of the trade space, before selection of a point design. At least one case study demonstrated the feasibility to generate such models in a concurrent engineering session. The experiment indicated that such a capability could yield valid system-level conclusions for a trade space composed of understood elements. Ongoing efforts are assessing the practicality of developing end-to-end system-level design models for use before even convening the first concurrent engineering session, starting with modeling an end-to-end Mars architecture.

  10. An assessment of CFD-based wall heat transfer models in piston engines

    Energy Technology Data Exchange (ETDEWEB)

    Sircar, Arpan [Pennsylvania State Univ., University Park, PA (United States); Paul, Chandan [Pennsylvania State Univ., University Park, PA (United States); Ferreyro-Fernandez, Sebastian [Pennsylvania State Univ., University Park, PA (United States); Imren, Abdurrahman [Pennsylvania State Univ., University Park, PA (United States); Haworth, Daniel C [Pennsylvania State Univ., University Park, PA (United States)

    2017-04-26

    The lack of accurate submodels for in-cylinder heat transfer has been identified as a key shortcoming in developing truly predictive, physics-based computational fluid dynamics (CFD) models that can be used to develop combustion systems for advanced high-efficiency, low-emissions engines. Only recently have experimental methods become available that enable accurate near-wall measurements to enhance simulation capability via advancing models. Initial results show crank-angle dependent discrepancies with respect to previously used boundary-layer models of up to 100%. However, available experimental data is quite sparse (only few data points on engine walls) and limited (available measurements are those of heat flux only). Predictive submodels are needed for medium-resolution ("engineering") LES and for unsteady Reynolds-averaged simulations (URANS). Recently, some research groups have performed DNS studies on engine-relevant conditions using simple geometries. These provide very useful data for benchmarking wall heat transfer models under such conditions. Further, a number of new and more sophisticated models have also become available in the literature which account for these engine-like conditions. Some of these have been incorporated while others of a more complex nature, which include solving additional partial differential equations (PDEs) within the thin boundary layer near the wall, are underway. These models will then be tested against the available DNS/experimental data in both SI (spark-ignition) and CI (compression-ignition) engines.

  11. A mixing based model for DME combustion in diesel engines

    DEFF Research Database (Denmark)

    Bek, Bjarne Hjort; Sorenson, Spencer C

    2001-01-01

    A series of studies has been conducted investigating the behavior of di-methyl ether (DME) fuel jets injected into quiescent combustion chambers. These studies have shown that it is possible to make a good estimate of the penetration of the jet based on existing correlations for diesel fuel...

  12. A Mixing Based Model for DME Combustion in Diesel Engines

    DEFF Research Database (Denmark)

    Bek, Bjarne H.; Sorenson, Spencer C.

    1998-01-01

    A series of studies has been conducted investigating the behavior of di-methyl ether (DME) fuel jets injected into quiescent combus-tion chambers. These studies have shown that it is possible to make a good estimate of the penetration of the jet based on existing correlations for diesel fuel...

  13. A Mixing Based Model for DME Combustion in Diesel Engines

    DEFF Research Database (Denmark)

    Bek, Bjarne H.; Sorenson, Spencer C.

    1998-01-01

    A series of studies has been conducted investigating the behavior of di-methyl ether (DME) fuel jets injected into quiescent combus-tion chambers. These studies have shown that it is possible to make a good estimate of the penetration of the jet based on existing correlations for diesel fuel, by ...

  14. Engine Modelling for Control Applications

    DEFF Research Database (Denmark)

    Hendricks, Elbert

    1997-01-01

    In earlier work published by the author and co-authors, a dynamic engine model called a Mean Value Engine Model (MVEM) was developed. This model is physically based and is intended mainly for control applications. In its newer form, it is easy to fit to many different engines and requires little ...

  15. Mean Value Engine Modelling of an SI Engine with EGR

    DEFF Research Database (Denmark)

    Føns, Michael; Müller, Martin; Chevalier, Alain

    1999-01-01

    Mean Value Engine Models (MVEMs) are simplified, dynamic engine models what are physically based. Such models are useful for control studies, for engine control system analysis and for model based engine control systems. Very few published MVEMs have included the effects of Exhaust Gas Recirculat...

  16. Particulate matter emission modelling based on soot and SOF from direct injection diesel engines

    International Nuclear Information System (INIS)

    Tan, P.Q.; Hu, Z.Y.; Deng, K.Y.; Lu, J.X.; Lou, D.M.; Wan, G.

    2007-01-01

    Particulate matter (PM) emission is one of the major pollutants from diesel engines, and it is harmful for human health and influences the atmospheric visibility. In investigations for reducing PM emission, a simulation model for PM emission is a useful tool. In this paper, a phenomenological, composition based PM model of direct injection (DI) diesel engines has been proposed and formulated to simulate PM emission. The PM emission model is based on a quasi-dimensional multi-zone combustion model using the formation mechanisms of the two main compositions of PM: soot and soluble organic fraction (SOF). First, the quasi-dimensional multi-zone combustion model is given. Then, two models for soot and SOF emissions are established, respectively, and after that, the two models are integrated into a single PM emission model. The soot emission model is given by the difference between a primary formation model and an oxidation model of soot. The soot primary formation model is the Hiroyasu soot formation model, and the Nagle and Strickland-Constable model is adopted for soot oxidation. The SOF emission model is based on an unburned hydrocarbons (HC) emission model, and the HC emission model is given by the difference between a HC primary formation model and a HC oxidation model. The HC primary formation model considers fuel injected and mixed beyond the lean combustion limit during ignition delay and fuel effusing from the nozzle sac volume at low pressure and low velocity. In order to validate the PM emission model, experiments were performed on a six cylinder, turbocharged and intercooled DI diesel engine. The simulation results show good agreement with the experimental data, which indicates the validity of the PM emission model. The calculation results show that the distinctions between PM and soot formation rates are mainly in the early combustion stage. The SOF formation has an important influence on the PM formation at lower loads, and soot formation dominates the

  17. A Co-modeling Method Based on Component Features for Mechatronic Devices in Aero-engines

    Science.gov (United States)

    Wang, Bin; Zhao, Haocen; Ye, Zhifeng

    2017-08-01

    Data-fused and user-friendly design of aero-engine accessories is required because of their structural complexity and stringent reliability. This paper gives an overview of a typical aero-engine control system and the development process of key mechatronic devices used. Several essential aspects of modeling and simulation in the process are investigated. Considering the limitations of a single theoretic model, feature-based co-modeling methodology is suggested to satisfy the design requirements and compensate for diversity of component sub-models for these devices. As an example, a stepper motor controlled Fuel Metering Unit (FMU) is modeled in view of the component physical features using two different software tools. An interface is suggested to integrate the single discipline models into the synthesized one. Performance simulation of this device using the co-model and parameter optimization for its key components are discussed. Comparison between delivery testing and the simulation shows that the co-model for the FMU has a high accuracy and the absolute superiority over a single model. Together with its compatible interface with the engine mathematical model, the feature-based co-modeling methodology is proven to be an effective technical measure in the development process of the device.

  18. Model Based Mission Assurance in a Model Based Systems Engineering (MBSE) Framework: State-of-the-Art Assessment

    Science.gov (United States)

    Cornford, Steven L.; Feather, Martin S.

    2016-01-01

    This report explores the current state of the art of Safety and Mission Assurance (S&MA) in projects that have shifted towards Model Based Systems Engineering (MBSE). Its goal is to provide insight into how NASA's Office of Safety and Mission Assurance (OSMA) should respond to this shift. In MBSE, systems engineering information is organized and represented in models: rigorous computer-based representations, which collectively make many activities easier to perform, less error prone, and scalable. S&MA practices must shift accordingly. The "Objective Structure Hierarchies" recently developed by OSMA provide the framework for understanding this shift. Although the objectives themselves will remain constant, S&MA practices (activities, processes, tools) to achieve them are subject to change. This report presents insights derived from literature studies and interviews. The literature studies gleaned assurance implications from reports of space-related applications of MBSE. The interviews with knowledgeable S&MA and MBSE personnel discovered concerns and ideas for how assurance may adapt. Preliminary findings and observations are presented on the state of practice of S&MA with respect to MBSE, how it is already changing, and how it is likely to change further. Finally, recommendations are provided on how to foster the evolution of S&MA to best fit with MBSE.

  19. Improved Traceability of Mission Concept to Requirements Using Model Based Systems Engineering

    Science.gov (United States)

    Reil, Robin

    2014-01-01

    Model Based Systems Engineering (MBSE) has recently been gaining significant support as a means to improve the traditional document-based systems engineering (DBSE) approach to engineering complex systems. In the spacecraft design domain, there are many perceived and propose benefits of an MBSE approach, but little analysis has been presented to determine the tangible benefits of such an approach (e.g. time and cost saved, increased product quality). This thesis presents direct examples of how developing a small satellite system model can improve traceability of the mission concept to its requirements. A comparison of the processes and approaches for MBSE and DBSE is made using the NASA Ames Research Center SporeSat CubeSat mission as a case study. A model of the SporeSat mission is built using the Systems Modeling Language standard and No Magics MagicDraw modeling tool. The model incorporates mission concept and requirement information from the missions original DBSE design efforts. Active dependency relationships are modeled to analyze the completeness and consistency of the requirements to the mission concept. Overall experience and methodology are presented for both the MBSE and original DBSE design efforts of SporeSat.

  20. Improved Traceability of a Small Satellite Mission Concept to Requirements Using Model Based System Engineering

    Science.gov (United States)

    Reil, Robin L.

    2014-01-01

    Model Based Systems Engineering (MBSE) has recently been gaining significant support as a means to improve the "traditional" document-based systems engineering (DBSE) approach to engineering complex systems. In the spacecraft design domain, there are many perceived and propose benefits of an MBSE approach, but little analysis has been presented to determine the tangible benefits of such an approach (e.g. time and cost saved, increased product quality). This paper presents direct examples of how developing a small satellite system model can improve traceability of the mission concept to its requirements. A comparison of the processes and approaches for MBSE and DBSE is made using the NASA Ames Research Center SporeSat CubeSat mission as a case study. A model of the SporeSat mission is built using the Systems Modeling Language standard and No Magic's MagicDraw modeling tool. The model incorporates mission concept and requirement information from the mission's original DBSE design efforts. Active dependency relationships are modeled to demonstrate the completeness and consistency of the requirements to the mission concept. Anecdotal information and process-duration metrics are presented for both the MBSE and original DBSE design efforts of SporeSat.

  1. 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

  2. EDUCATIONAL COMPLEX ON ELECTRICAL ENGINEERING AND ELECTRONICS BASED ON MODELING IN PROGRAM TINA

    Directory of Open Access Journals (Sweden)

    Vladimir A. Alekhin

    2014-01-01

    Full Text Available The educational complex on the electrical engineering and electronics has been developed. It contains a course of lectures and lecture notes in the electronic form, a new computer laboratory practical work and practical training. All electronic manuals are based on modeling of electric and electronic circuits in the new effective program TINA. The educational complex is being successfully used in educational process on internal and distant learning. 

  3. Model-based engineering:a strategy for RRW and future weapons programs.

    Energy Technology Data Exchange (ETDEWEB)

    Harris, Rick; Martinez, Jacky R.

    2007-05-01

    To meet Sandia's engineering challenges it is crucial that we shorten the product realization process. The challenge of RRW is to produce exceptional high quality designs and respond to changes quickly. Computer aided design models are an important element in realizing these objectives. Advances in the use of three dimensional geometric models on the Reliable Robust Warhead (RRW) activity have resulted in business advantage. This approach is directly applicable to other programs within the Laboratories. This paper describes the RRW approach and rationale. Keys to this approach are defined operational states that indicate a pathway for greater model-based realization and responsive infrastructure.

  4. Engineering model for body armor

    NARCIS (Netherlands)

    Roebroeks, G.H.J.J.; Carton, E.P.

    2014-01-01

    TNO has developed an engineering model for flexible body armor, as one of their energy based engineering models that describe the physics of projectile to target interactions (weaves, metals, ceramics). These models form the basis for exploring the possibilities for protection improvement. This

  5. 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.

  6. Model-Based Engine Control Architecture with an Extended Kalman Filter

    Science.gov (United States)

    Csank, Jeffrey T.; Connolly, Joseph W.

    2016-01-01

    This paper discusses the design and implementation of an extended Kalman filter (EKF) for model-based engine control (MBEC). Previously proposed MBEC architectures feature an optimal tuner Kalman Filter (OTKF) to produce estimates of both unmeasured engine parameters and estimates for the health of the engine. The success of this approach relies on the accuracy of the linear model and the ability of the optimal tuner to update its tuner estimates based on only a few sensors. Advances in computer processing are making it possible to replace the piece-wise linear model, developed off-line, with an on-board nonlinear model running in real-time. This will reduce the estimation errors associated with the linearization process, and is typically referred to as an extended Kalman filter. The nonlinear extended Kalman filter approach is applied to the Commercial Modular Aero-Propulsion System Simulation 40,000 (C-MAPSS40k) and compared to the previously proposed MBEC architecture. The results show that the EKF reduces the estimation error, especially during transient operation.

  7. Using A Model-Based Systems Engineering Approach For Exploration Medical System Development

    Science.gov (United States)

    Hanson, A.; Mindock, J.; McGuire, K.; Reilly, J.; Cerro, J.; Othon, W.; Rubin, D.; Urbina, M.; Canga, M.

    2017-01-01

    NASA's Human Research Program's Exploration Medical Capabilities (ExMC) element is defining the medical system needs for exploration class missions. ExMC's Systems Engineering (SE) team will play a critical role in successful design and implementation of the medical system into exploration vehicles. The team's mission is to "Define, develop, validate, and manage the technical system design needed to implement exploration medical capabilities for Mars and test the design in a progression of proving grounds." Development of the medical system is being conducted in parallel with exploration mission architecture and vehicle design development. Successful implementation of the medical system in this environment will require a robust systems engineering approach to enable technical communication across communities to create a common mental model of the emergent engineering and medical systems. Model-Based Systems Engineering (MBSE) improves shared understanding of system needs and constraints between stakeholders and offers a common language for analysis. The ExMC SE team is using MBSE techniques to define operational needs, decompose requirements and architecture, and identify medical capabilities needed to support human exploration. Systems Modeling Language (SysML) is the specific language the SE team is utilizing, within an MBSE approach, to model the medical system functional needs, requirements, and architecture. Modeling methods are being developed through the practice of MBSE within the team, and tools are being selected to support meta-data exchange as integration points to other system models are identified. Use of MBSE is supporting the development of relationships across disciplines and NASA Centers to build trust and enable teamwork, enhance visibility of team goals, foster a culture of unbiased learning and serving, and be responsive to customer needs. The MBSE approach to medical system design offers a paradigm shift toward greater integration between

  8. Industrial Adoption of Model-Based Systems Engineering: Challenges and Strategies

    Science.gov (United States)

    Maheshwari, Apoorv

    As design teams are becoming more globally integrated, one of the biggest challenges is to efficiently communicate across the team. The increasing complexity and multi-disciplinary nature of the products are also making it difficult to keep track of all the information generated during the design process by these global team members. System engineers have identified Model-based Systems Engineering (MBSE) as a possible solution where the emphasis is placed on the application of visual modeling methods and best practices to systems engineering (SE) activities right from the beginning of the conceptual design phases through to the end of the product lifecycle. Despite several advantages, there are multiple challenges restricting the adoption of MBSE by industry. We mainly consider the following two challenges: a) Industry perceives MBSE just as a diagramming tool and does not see too much value in MBSE; b) Industrial adopters are skeptical if the products developed using MBSE approach will be accepted by the regulatory bodies. To provide counter evidence to the former challenge, we developed a generic framework for translation from an MBSE tool (Systems Modeling Language, SysML) to an analysis tool (Agent-Based Modeling, ABM). The translation is demonstrated using a simplified air traffic management problem and provides an example of a potential quite significant value: the ability to use MBSE representations directly in an analysis setting. For the latter challenge, we are developing a reference model that uses SysML to represent a generic infusion pump and SE process for planning, developing, and obtaining regulatory approval of a medical device. This reference model demonstrates how regulatory requirements can be captured effectively through model-based representations. We will present another case study at the end where we will apply the knowledge gained from both case studies to a UAV design problem.

  9. A Systematic Approach for Model-Based Aircraft Engine Performance Estimation

    Science.gov (United States)

    Simon, Donald L.; Garg, Sanjay

    2010-01-01

    A requirement for effective aircraft engine performance estimation is the ability to account for engine degradation, generally described in terms of unmeasurable health parameters such as efficiencies and flow capacities related to each major engine module. This paper presents a linear point design methodology for minimizing the degradation-induced error in model-based aircraft engine performance estimation applications. The technique specifically focuses on the underdetermined estimation problem, where there are more unknown health parameters than available sensor measurements. A condition for Kalman filter-based estimation is that the number of health parameters estimated cannot exceed the number of sensed measurements. In this paper, the estimated health parameter vector will be replaced by a reduced order tuner vector whose dimension is equivalent to the sensed measurement vector. The reduced order tuner vector is systematically selected to minimize the theoretical mean squared estimation error of a maximum a posteriori estimator formulation. This paper derives theoretical estimation errors at steady-state operating conditions, and presents the tuner selection routine applied to minimize these values. Results from the application of the technique to an aircraft engine simulation are presented and compared to the estimation accuracy achieved through conventional maximum a posteriori and Kalman filter estimation approaches. Maximum a posteriori estimation results demonstrate that reduced order tuning parameter vectors can be found that approximate the accuracy of estimating all health parameters directly. Kalman filter estimation results based on the same reduced order tuning parameter vectors demonstrate that significantly improved estimation accuracy can be achieved over the conventional approach of selecting a subset of health parameters to serve as the tuner vector. However, additional development is necessary to fully extend the methodology to Kalman filter-based

  10. Improving Metabolic Pathway Efficiency by Statistical Model-Based Multivariate Regulatory Metabolic Engineering.

    Science.gov (United States)

    Xu, Peng; Rizzoni, Elizabeth Anne; Sul, Se-Yeong; Stephanopoulos, Gregory

    2017-01-20

    Metabolic engineering entails target modification of cell metabolism to maximize the production of a specific compound. For empowering combinatorial optimization in strain engineering, tools and algorithms are needed to efficiently sample the multidimensional gene expression space and locate the desirable overproduction phenotype. We addressed this challenge by employing design of experiment (DoE) models to quantitatively correlate gene expression with strain performance. By fractionally sampling the gene expression landscape, we statistically screened the dominant enzyme targets that determine metabolic pathway efficiency. An empirical quadratic regression model was subsequently used to identify the optimal gene expression patterns of the investigated pathway. As a proof of concept, our approach yielded the natural product violacein at 525.4 mg/L in shake flasks, a 3.2-fold increase from the baseline strain. Violacein production was further increased to 1.31 g/L in a controlled benchtop bioreactor. We found that formulating discretized gene expression levels into logarithmic variables (Linlog transformation) was essential for implementing this DoE-based optimization procedure. The reported methodology can aid multivariate combinatorial pathway engineering and may be generalized as a standard procedure for accelerating strain engineering and improving metabolic pathway efficiency.

  11. The Design and Engineering of Mobile Data Services: Developing an Ontology Based on Business Model Thinking

    Science.gov (United States)

    Al-Debei, Mutaz M.; Fitzgerald, Guy

    This paper addresses the design and engineering problem related to mobile data services. The aim of the research is to inform and advise mobile service design and engineering by looking at this issue from a rigorous and holistic perspective. To this aim, this paper develops an ontology based on business model thinking. The developed ontology identifies four primary dimensions in designing business models of mobile data services: value proposition, value network, value architecture, and value finance. Within these dimensions, 15 key design concepts are identified along with their interrelationships and rules in the telecommunication service business model domain and unambiguous semantics are produced. The developed ontology is of value to academics and practitioners alike, particularly those interested in strategic-oriented IS/IT and business developments in telecommunications. Employing the developed ontology would systemize mobile service engineering functions and make them more manageable, effective, and creative. The research approach to building the mobile service business model ontology essentially follows the design science paradigm. Within this paradigm, we incorporate a number of different research methods, so the employed methodology might be better characterized as a pluralist approach.

  12. An Arts-Based Instructional Model for Student Creativity in Engineering Design

    Directory of Open Access Journals (Sweden)

    Brian Laduca

    2017-02-01

    Full Text Available Over the past twenty years, nearly all job growth in the United States has emerged from new companies and organizations with assumedly innovative products, services, and practices. Yet, the nurturing of student creative thinking and problem solving is infrequent in engineering education. Inherent to developing these creativity skills and attributes is the need to be exposed to difference — in people and environment. Engineering education rarely offers such opportunities. Additionally, engineering students are rarely presented opportunities to develop designs responding to real human problems. This paper puts forth a new instructional model to address these needs by utilizing arts processes and practices as catalysts for both creativity development in students and transdisciplinary collaboration on problems addressing deep human needs. This model is premised on the substantiated role of the arts in developing creativity and growing understanding of the human condition. This art-based instructional model was piloted as exploratory pedagogical research during the summers of 2015 and 2016 as a partnership between the Arts Nexus (IAN and the School of Engineering at the University of Dayton. In each year, this program supported twelve student interns from engineering, business, science, the arts, and the humanities to develop innovative technologies and services meeting client needs. Student growth in creative problem-solving and transdisciplinary collaboration, as well as the success of the completed innovation technology prototype were assessed by the project mentors and participating students via survey evaluations and narrative responses. The assessment results revealed substantial student growth in student creativity and transdisciplinary collaboration and a remarkably strong evaluation of the success of the students’ innovations. Also realized for all students was a transformation in their perception of their place in the world as

  13. Extending the Activity Theory Based Model for Serious Games Design in Engineering to Integrate Analytics

    Directory of Open Access Journals (Sweden)

    Michael Callaghan

    2018-02-01

    Full Text Available Serious Games (SG have been shown to have instructional potential and a number of formal models, frameworks and methodologies have emerged to support their design and analysis. The Activity Theory-based Model of Serious Games (ATMSG facilitates a systematic and detailed representation of educational SG describing how game elements are connected together to contribute to pedagogical goals. This paper proposes and presents an extension to the ATMSG framework to facilitate the identification, selection and integration of analytics into serious games. A practical example of the approach in use in the analysis and design phase of a SG for engineering is demonstrated.

  14. Category Theory as a Formal Mathematical Foundation for Model-Based Systems Engineering

    KAUST Repository

    Mabrok, Mohamed

    2017-01-09

    In this paper, we introduce Category Theory as a formal foundation for model-based systems engineering. A generalised view of the system based on category theory is presented, where any system can be considered as a category. The objects of the category represent all the elements and components of the system and the arrows represent the relations between these components (objects). The relationship between these objects are the arrows or the morphisms in the category. The Olog is introduced as a formal language to describe a given real-world situation description and requirement writing. A simple example is provided.

  15. Vibration-based health monitoring and model refinement of civil engineering structures

    Energy Technology Data Exchange (ETDEWEB)

    Farrar, C.R.; Doebling, S.W.

    1997-10-01

    Damage or fault detection, as determined by changes in the dynamic properties of structures, is a subject that has received considerable attention in the technical literature beginning approximately 30 years ago. The basic idea is that changes in the structure`s properties, primarily stiffness, will alter the dynamic properties of the structure such as resonant frequencies and mode shapes, and properties derived from these quantities such as modal-based flexibility. Recently, this technology has been investigated for applications to health monitoring of large civil engineering structures. This presentation will discuss such a study undertaken by engineers from New Mexico Sate University, Sandia National Laboratory and Los Alamos National Laboratory. Experimental modal analyses were performed in an undamaged interstate highway bridge and immediately after four successively more severe damage cases were inflicted in the main girder of the structure. Results of these tests provide insight into the abilities of modal-based damage ID methods to identify damage and the current limitations of this technology. Closely related topics that will be discussed are the use of modal properties to validate computer models of the structure, the use of these computer models in the damage detection process, and the general lack of experimental investigation of large civil engineering structures.

  16. Reverse engineering Boolean networks: from Bernoulli mixture models to rule based systems.

    Directory of Open Access Journals (Sweden)

    Mehreen Saeed

    Full Text Available A Boolean network is a graphical model for representing and analyzing the behavior of gene regulatory networks (GRN. In this context, the accurate and efficient reconstruction of a Boolean network is essential for understanding the gene regulation mechanism and the complex relations that exist therein. In this paper we introduce an elegant and efficient algorithm for the reverse engineering of Boolean networks from a time series of multivariate binary data corresponding to gene expression data. We call our method ReBMM, i.e., reverse engineering based on Bernoulli mixture models. The time complexity of most of the existing reverse engineering techniques is quite high and depends upon the indegree of a node in the network. Due to the high complexity of these methods, they can only be applied to sparsely connected networks of small sizes. ReBMM has a time complexity factor, which is independent of the indegree of a node and is quadratic in the number of nodes in the network, a big improvement over other techniques and yet there is little or no compromise in accuracy. We have tested ReBMM on a number of artificial datasets along with simulated data derived from a plant signaling network. We also used this method to reconstruct a network from real experimental observations of microarray data of the yeast cell cycle. Our method provides a natural framework for generating rules from a probabilistic model. It is simple, intuitive and illustrates excellent empirical results.

  17. A Dynamic Model for the Evaluation of Aircraft Engine Icing Detection and Control-Based Mitigation Strategies

    Science.gov (United States)

    Simon, Donald L.; Rinehart, Aidan W.; Jones, Scott M.

    2017-01-01

    Aircraft flying in regions of high ice crystal concentrations are susceptible to the buildup of ice within the compression system of their gas turbine engines. This ice buildup can restrict engine airflow and cause an uncommanded loss of thrust, also known as engine rollback, which poses a potential safety hazard. The aviation community is conducting research to understand this phenomena, and to identify avoidance and mitigation strategies to address the concern. To support this research, a dynamic turbofan engine model has been created to enable the development and evaluation of engine icing detection and control-based mitigation strategies. This model captures the dynamic engine response due to high ice water ingestion and the buildup of ice blockage in the engines low pressure compressor. It includes a fuel control system allowing engine closed-loop control effects during engine icing events to be emulated. The model also includes bleed air valve and horsepower extraction actuators that, when modulated, change overall engine operating performance. This system-level model has been developed and compared against test data acquired from an aircraft turbofan engine undergoing engine icing studies in an altitude test facility and also against outputs from the manufacturers customer deck. This paper will describe the model and show results of its dynamic response under open-loop and closed-loop control operating scenarios in the presence of ice blockage buildup compared against engine test cell data. Planned follow-on use of the model for the development and evaluation of icing detection and control-based mitigation strategies will also be discussed. The intent is to combine the model and control mitigation logic with an engine icing risk calculation tool capable of predicting the risk of engine icing based on current operating conditions. Upon detection of an operating region of risk for engine icing events, the control mitigation logic will seek to change the

  18. Multidisciplinary model-based-engineering for laser weapon systems: recent progress

    Science.gov (United States)

    Coy, Steve; Panthaki, Malcolm

    2013-09-01

    We are working to develop a comprehensive, integrated software framework and toolset to support model-based engineering (MBE) of laser weapons systems. MBE has been identified by the Office of the Director, Defense Science and Engineering as one of four potentially "game-changing" technologies that could bring about revolutionary advances across the entire DoD research and development and procurement cycle. To be effective, however, MBE requires robust underlying modeling and simulation technologies capable of modeling all the pertinent systems, subsystems, components, effects, and interactions at any level of fidelity that may be required in order to support crucial design decisions at any point in the system development lifecycle. Very often the greatest technical challenges are posed by systems involving interactions that cut across two or more distinct scientific or engineering domains; even in cases where there are excellent tools available for modeling each individual domain, generally none of these domain-specific tools can be used to model the cross-domain interactions. In the case of laser weapons systems R&D these tools need to be able to support modeling of systems involving combined interactions among structures, thermal, and optical effects, including both ray optics and wave optics, controls, atmospheric effects, target interaction, computational fluid dynamics, and spatiotemporal interactions between lasing light and the laser gain medium. To address this problem we are working to extend Comet™, to add the addition modeling and simulation capabilities required for this particular application area. In this paper we will describe our progress to date.

  19. Model-Based Engineering and Manufacturing CAD/CAM Benchmark.; FINAL

    International Nuclear Information System (INIS)

    Domm, T.C.; Underwood, R.S.

    1999-01-01

    The Benchmark Project was created from a desire to identify best practices and improve the overall efficiency and performance of the Y-12 Plant's systems and personnel supporting the manufacturing mission. The mission of the benchmark team was to search out industry leaders in manufacturing and evaluate their engineering practices and processes to determine direction and focus for Y-12 modernization efforts. The companies visited included several large established companies and a new, small, high-tech machining firm. As a result of this effort, changes are recommended that will enable Y-12 to become a more modern, responsive, cost-effective manufacturing facility capable of supporting the needs of the Nuclear Weapons Complex (NWC) into the 21st century. The benchmark team identified key areas of interest, both focused and general. The focus areas included Human Resources, Information Management, Manufacturing Software Tools, and Standards/Policies and Practices. Areas of general interest included Infrastructure, Computer Platforms and Networking, and Organizational Structure. The results of this benchmark showed that all companies are moving in the direction of model-based engineering and manufacturing. There was evidence that many companies are trying to grasp how to manage current and legacy data. In terms of engineering design software tools, the companies contacted were somewhere between 3-D solid modeling and surfaced wire-frame models. The manufacturing computer tools were varied, with most companies using more than one software product to generate machining data and none currently performing model-based manufacturing (MBM) from a common model. The majority of companies were closer to identifying or using a single computer-aided design (CAD) system than a single computer-aided manufacturing (CAM) system. The Internet was a technology that all companies were looking to either transport information more easily throughout the corporation or as a conduit for

  20. Development and Application of Back-Propagation-Based Artificial Neural Network Models in Solving Engineering

    Directory of Open Access Journals (Sweden)

    Saleh Mohammed Al-Alawi

    2002-06-01

    Full Text Available Artificial Neural Networks (ANNs are computer software programs that mimic the human brain's ability to classify patterns or to make forecasts or decisions based on past experience.  The development of this research area can be attributed to two factors, sufficient computer power to begin practical ANN-based research in the late 1970s and the development of back-propagation in 1986 that enabled ANN models to solve everyday business, scientific, and industrial problems.  Since then, significant applications have been implemented in several fields of study, and many useful intelligent applications and systems have been developed.  The objective of this paper is to generate awareness and to encourage applications development using artificial intelligence-based systems.  Therefore, this paper provides basic ANN concepts, outlines steps used for ANN model development, and lists examples of engineering applications based on the use of the back-propagation paradigm conducted in Oman.  The paper is intended to provide guidelines and necessary references and resources for novice individuals interested in conducting research in engineering or other fields of study using back-propagation artificial neural networks.

  1. A new closed-form analytical thermal model for simulating Stirling engines based on polytropic-finite speed thermodynamics

    International Nuclear Information System (INIS)

    Hosseinzade, Hadi; Sayyaadi, Hoseyn; Babaelahi, Mojtaba

    2015-01-01

    Highlights: • A closed-form thermal model was presented for Stirling engines. • The new model was used to simulate the GPU-3 Stirling engine. • Results were compared with experimental data as well as other models. • The new model was more accurate and simple in calculation than other models. • Effects of the engines’ parameters on operation of engine were evaluated. - Abstract: Thermal models for the simulation of Stirling engines need to have greater accuracy along with simple and low-cost calculation. In this regard, a new closed-form thermal model was presented for the thermal simulation of Stirling engines. The new model called PFST (polytropic-finite speed thermodynamics) was developed based on the combination of polytropic analysis of expansion/compression processes and the concept of finite speed thermodynamics (FST). Therefore, compression/expansion works of compression/expansion processes and transferred heat into the heater of Stirling engines were determined based on polytropic analysis, instead of isothermal processes of the ideal Stirling cycle. The calculated work of polytropic processes was corrected to include the effects of internal irreversibilities including pressure throttling in heat exchangers, mechanical friction, and finite motion of the pistons. Output power and thermal efficiency of Stirling engines were calculated as functions of various engine parameters. The developed PFST model was implemented on a prototype Stirling engine, called GPU-3 engine, and the obtained results were compared with those of other closed-form and numerical models as well as experimental data. It was found that the new closed-form model, in addition to its simple and low-cost calculation, had the same order of accuracy as recently developed numerical models

  2. MODELS OF PROJECT REVERSE ENGINEERING

    Directory of Open Access Journals (Sweden)

    Віктор Володимирович ІВАНОВ

    2017-03-01

    Full Text Available Reverse engineering decided important scientific and technical problems of increasing the cost of the existing technical product by transforming it into a product with other features or design. Search ideas of the new application of existing products on the base of heuristic analysis were created. The concept of reverse engineering and its division into three types: conceptual, aggregate and complete was expanded. The use of heuristic methods for reverse engineering concept was showed. The modification model of Reverse engineering based on the model of РМВОК was developed. Our model includes two new phases: identification and transformation. At the identification phase, technical control is made. At the transformation phase, search heuristic idea of the new applied existing technical product was made. The model of execution phase that included heuristic methods, metrological equipment, and CAD/CAM/CAE program complex was created. The model that connected economic indicators of reverse engineering project was developed.

  3. Effectiveness and Utility of a Case-Based Model for Delivering Engineering Ethics Professional Development Units

    Directory of Open Access Journals (Sweden)

    Heidi Ann Hahn

    2014-10-01

    Full Text Available This article describes an action research project conducted at Los Alamos National Laboratory (LANL to resolve a problem with the ability of licensed and/or certified engineers to obtain the ethics-related professional development units or hours (PDUs or PDHs needed to maintain their credentials. Because of the recurring requirement and the static nature of the information, an initial, in-depth training followed by annually updated refresher training was proposed. A case model approach, with online delivery, was selected as the optimal pedagogical model for the refresher training. In the first two years, the only data that was collected was throughput and information retention. Response rates indicated that the approach was effective in helping licensed professional engineers obtain the needed PDUs. The rates of correct responses suggested that knowledge transfer regarding ethical reasoning had occurred in the initial training and had been retained in the refresher. In FY13, after completing the refresher, learners received a survey asking their opinion of the effectiveness and utility of the course, as well as their impressions of the case study format vs. the typical presentation format. Results indicate that the courses have been favorably received and that the case study method supports most of the pedagogical needs of adult learners as well as, if not better than, presentation-based instruction. Future plans for improvement are focused on identifying and evaluating methods for enriching online delivery of the engineering ethics cases.

  4. Effectiveness and Utility of a Case-Based Model for Delivering Engineering Ethics Professional Development Units

    Directory of Open Access Journals (Sweden)

    Heidi Ann Hahn

    2015-04-01

    Full Text Available This article describes an action research project conducted at Los Alamos National Laboratory (LANL to resolve a problem with the ability of licensed and/or certified engineers to obtain the ethics-related professional development units or hours (PDUs or PDHs needed to maintain their credentials. Because of the recurring requirement and the static nature of the information, an initial, in-depth training followed by annually updated refresher training was proposed. A case model approach, with online delivery, was selected as the optimal pedagogical model for the refresher training. In the first two years, the only data that was collected was throughput and information retention. Response rates indicated that the approach was effective in helping licensed professional engineers obtain the needed PDUs. The rates of correct responses suggested that knowledge transfer regarding ethical reasoning had occurred in the initial training and had been retained in the refresher. In FY13, after completing the refresher, learners received a survey asking their opinion of the effectiveness and utility of the course, as well as their impressions of the case study format vs. the typical presentation format. Results indicate that the courses have been favorably received and that the case study method supports most of the pedagogical needs of adult learners as well as, if not better than, presentation-based instruction. Future plans for improvement are focused on identifying and evaluating methods for enriching online delivery of the engineering ethics cases.

  5. Using model based systems engineering for the development of the Large Synoptic Survey Telescope's operational plan

    Science.gov (United States)

    Selvy, Brian M.; Claver, Charles; Willman, Beth; Petravick, Don; Johnson, Margaret; Reil, Kevin; Marshall, Stuart; Thomas, Sandrine; Lotz, Paul; Schumacher, German; Lim, Kian-Tat; Jenness, Tim; Jacoby, Suzanne; Emmons, Ben; Axelrod, Tim

    2016-08-01

    We† provide an overview of the Model Based Systems Engineering (MBSE) language, tool, and methodology being used in our development of the Operational Plan for Large Synoptic Survey Telescope (LSST) operations. LSST's Systems Engineering (SE) team is using a model-based approach to operational plan development to: 1) capture the topdown stakeholders' needs and functional allocations defining the scope, required tasks, and personnel needed for operations, and 2) capture the bottom-up operations and maintenance activities required to conduct the LSST survey across its distributed operations sites for the full ten year survey duration. To accomplish these complimentary goals and ensure that they result in self-consistent results, we have developed a holistic approach using the Sparx Enterprise Architect modeling tool and Systems Modeling Language (SysML). This approach utilizes SysML Use Cases, Actors, associated relationships, and Activity Diagrams to document and refine all of the major operations and maintenance activities that will be required to successfully operate the observatory and meet stakeholder expectations. We have developed several customized extensions of the SysML language including the creation of a custom stereotyped Use Case element with unique tagged values, as well as unique association connectors and Actor stereotypes. We demonstrate this customized MBSE methodology enables us to define: 1) the rolls each human Actor must take on to successfully carry out the activities associated with the Use Cases; 2) the skills each Actor must possess; 3) the functional allocation of all required stakeholder activities and Use Cases to organizational entities tasked with carrying them out; and 4) the organization structure required to successfully execute the operational survey. Our approach allows for continual refinement utilizing the systems engineering spiral method to expose finer levels of detail as necessary. For example, the bottom-up, Use Case

  6. Design of personalized search engine based on user-webpage dynamic model

    Science.gov (United States)

    Li, Jihan; Li, Shanglin; Zhu, Yingke; Xiao, Bo

    2013-12-01

    Personalized search engine focuses on establishing a user-webpage dynamic model. In this model, users' personalized factors are introduced so that the search engine is better able to provide the user with targeted feedback. This paper constructs user and webpage dynamic vector tables, introduces singular value decomposition analysis in the processes of topic categorization, and extends the traditional PageRank algorithm.

  7. Using Model-Based System Engineering to Provide Artifacts for NASA Project Life-Cycle and Technical Reviews Presentation

    Science.gov (United States)

    Parrott, Edith L.; Weiland, Karen J.

    2017-01-01

    This is the presentation for the AIAA Space conference in September 2017. It highlights key information from Using Model-Based Systems Engineering to Provide Artifacts for NASA Project Life-cycle and Technical Reviews paper.

  8. Two-vehicle injury severity models based on integration of pavement management and traffic engineering factors.

    Science.gov (United States)

    Jiang, Ximiao; Huang, Baoshan; Yan, Xuedong; Zaretzki, Russell L; Richards, Stephen

    2013-01-01

    The severity of traffic-related injuries has been studied by many researchers in recent decades. However, the evaluation of many factors is still in dispute and, until this point, few studies have taken into account pavement management factors as points of interest. The objective of this article is to evaluate the combined influences of pavement management factors and traditional traffic engineering factors on the injury severity of 2-vehicle crashes. This study examines 2-vehicle rear-end, sideswipe, and angle collisions that occurred on Tennessee state routes from 2004 to 2008. Both the traditional ordered probit (OP) model and Bayesian ordered probit (BOP) model with weak informative prior were fitted for each collision type. The performances of these models were evaluated based on the parameter estimates and deviances. The results indicated that pavement management factors played identical roles in all 3 collision types. Pavement serviceability produces significant positive effects on the severity of injuries. The pavement distress index (PDI), rutting depth (RD), and rutting depth difference between right and left wheels (RD_df) were not significant in any of these 3 collision types. The effects of traffic engineering factors varied across collision types, except that a few were consistently significant in all 3 collision types, such as annual average daily traffic (AADT), rural-urban location, speed limit, peaking hour, and light condition. The findings of this study indicated that improved pavement quality does not necessarily lessen the severity of injuries when a 2-vehicle crash occurs. The effects of traffic engineering factors are not universal but vary by the type of crash. The study also found that the BOP model with a weak informative prior can be used as an alternative but was not superior to the traditional OP model in terms of overall performance.

  9. Preliminary Modelling Results for an Otto Cycle/Stirling Cycle Hybrid-engine-based Power Generation System

    OpenAIRE

    Cullen, Barry; McGovern, Jim; Feidt, Michel; Petrescu, Stoian

    2009-01-01

    This paper presents preliminary data and results for a system mathematical model for a proposed Otto Cycle / Stirling Cycle hybrid-engine-based power generation system. The system is a combined cycle system with the Stirling cycle machine operating as a bottoming cycle on the Otto cycle exhaust. The application considered is that of a stationary power generation scenario wherein the Stirling cycle engine operates as a waste heat recovery device on the exhaust stream of the Otto cycle engine. ...

  10. Identifying potential misfit items in cognitive process of learning engineering mathematics based on Rasch model

    Science.gov (United States)

    Ataei, Sh; Mahmud, Z.; Khalid, M. N.

    2014-04-01

    The students learning outcomes clarify what students should know and be able to demonstrate after completing their course. So, one of the issues on the process of teaching and learning is how to assess students' learning. This paper describes an application of the dichotomous Rasch measurement model in measuring the cognitive process of engineering students' learning of mathematics. This study provides insights into the perspective of 54 engineering students' cognitive ability in learning Calculus III based on Bloom's Taxonomy on 31 items. The results denote that some of the examination questions are either too difficult or too easy for the majority of the students. This analysis yields FIT statistics which are able to identify if there is data departure from the Rasch theoretical model. The study has identified some potential misfit items based on the measurement of ZSTD where the removal misfit item was accomplished based on the MNSQ outfit of above 1.3 or less than 0.7 logit. Therefore, it is recommended that these items be reviewed or revised to better match the range of students' ability in the respective course.

  11. Identifying potential misfit items in cognitive process of learning engineering mathematics based on Rasch model

    International Nuclear Information System (INIS)

    Ataei, Sh; Mahmud, Z; Khalid, M N

    2014-01-01

    The students learning outcomes clarify what students should know and be able to demonstrate after completing their course. So, one of the issues on the process of teaching and learning is how to assess students' learning. This paper describes an application of the dichotomous Rasch measurement model in measuring the cognitive process of engineering students' learning of mathematics. This study provides insights into the perspective of 54 engineering students' cognitive ability in learning Calculus III based on Bloom's Taxonomy on 31 items. The results denote that some of the examination questions are either too difficult or too easy for the majority of the students. This analysis yields FIT statistics which are able to identify if there is data departure from the Rasch theoretical model. The study has identified some potential misfit items based on the measurement of ZSTD where the removal misfit item was accomplished based on the MNSQ outfit of above 1.3 or less than 0.7 logit. Therefore, it is recommended that these items be reviewed or revised to better match the range of students' ability in the respective course.

  12. Goal-Based Domain Modeling as a Basis for Cross-Disciplinary Systems Engineering

    Science.gov (United States)

    Jarke, Matthias; Nissen, Hans W.; Rose, Thomas; Schmitz, Dominik

    Small and medium-sized enterprises (SMEs) are important drivers for innovation. In particular, project-driven SMEs that closely cooperate with their customers have specific needs in regard to information engineering of their development process. They need a fast requirements capture since this is most often included in the (unpaid) offer development phase. At the same time, they need to maintain and reuse the knowledge and experiences they have gathered in previous projects extensively as it is their core asset. The situation is complicated further if the application field crosses disciplinary boundaries. To bridge the gaps and perspectives, we focus on shared goals and dependencies captured in models at a conceptual level. Such a model-based approach also offers a smarter connection to subsequent development stages, including a high share of automated code generation. In the approach presented here, the agent- and goal-oriented formalism i * is therefore extended by domain models to facilitate information organization. This extension permits a domain model-based similarity search, and a model-based transformation towards subsequent development stages. Our approach also addresses the evolution of domain models reflecting the experiences from completed projects. The approach is illustrated with a case study on software-intensive control systems in an SME of the automotive domain.

  13. Constitutive Relation of Engineering Material Based on SIR Model and HAM

    Directory of Open Access Journals (Sweden)

    Haoxiang He

    2014-01-01

    Full Text Available As an epidemic mathematical model, the SIR model represents the transition of the Susceptible, Infected, and Recovered. The profound implication of the SIR model is viewed as the propagation and dynamic evolutionary process of the different internal components and the characteristics in a complex system subject to external effect. The uniaxial stress-strain curve of engineering material represents the basic constitutive relation, which also represents the damage propagation in the units of the damaged member. Hence, a novel dynamic stress-strain model is established based on the SIR model. The analytical solution and the approximate solution for the proposed model are represented according to the homotopy analysis method (HAM, and the relationship of the solution and the size effect and the strain rate is discussed. In addition, an experiment on the size effect of confined concrete is carried out and the solution of SIR model is suitable for simulation. The results show that the mechanical mechanism of the parameters of the uniaxial stress-strain model proposed in this paper reflects the actual characteristics of the materials. The solution of the SIR model can fully and accurately show the change of the mechanical performance and the influence of the size effect and the strain rate.

  14. Implementing model-based system engineering for the whole lifecycle of a spacecraft

    Science.gov (United States)

    Fischer, P. M.; Lüdtke, D.; Lange, C.; Roshani, F.-C.; Dannemann, F.; Gerndt, A.

    2017-09-01

    Design information of a spacecraft is collected over all phases in the lifecycle of a project. A lot of this information is exchanged between different engineering tasks and business processes. In some lifecycle phases, model-based system engineering (MBSE) has introduced system models and databases that help to organize such information and to keep it consistent for everyone. Nevertheless, none of the existing databases approached the whole lifecycle yet. Virtual Satellite is the MBSE database developed at DLR. It has been used for quite some time in Phase A studies and is currently extended for implementing it in the whole lifecycle of spacecraft projects. Since it is unforeseeable which future use cases such a database needs to support in all these different projects, the underlying data model has to provide tailoring and extension mechanisms to its conceptual data model (CDM). This paper explains the mechanisms as they are implemented in Virtual Satellite, which enables extending the CDM along the project without corrupting already stored information. As an upcoming major use case, Virtual Satellite will be implemented as MBSE tool in the S2TEP project. This project provides a new satellite bus for internal research and several different payload missions in the future. This paper explains how Virtual Satellite will be used to manage configuration control problems associated with such a multi-mission platform. It discusses how the S2TEP project starts using the software for collecting the first design information from concurrent engineering studies, then making use of the extension mechanisms of the CDM to introduce further information artefacts such as functional electrical architecture, thus linking more and more processes into an integrated MBSE approach.

  15. Analyzing Cyber Security Threats on Cyber-Physical Systems Using Model-Based Systems Engineering

    Science.gov (United States)

    Kerzhner, Aleksandr; Pomerantz, Marc; Tan, Kymie; Campuzano, Brian; Dinkel, Kevin; Pecharich, Jeremy; Nguyen, Viet; Steele, Robert; Johnson, Bryan

    2015-01-01

    The spectre of cyber attacks on aerospace systems can no longer be ignored given that many of the components and vulnerabilities that have been successfully exploited by the adversary on other infrastructures are the same as those deployed and used within the aerospace environment. An important consideration with respect to the mission/safety critical infrastructure supporting space operations is that an appropriate defensive response to an attack invariably involves the need for high precision and accuracy, because an incorrect response can trigger unacceptable losses involving lives and/or significant financial damage. A highly precise defensive response, considering the typical complexity of aerospace environments, requires a detailed and well-founded understanding of the underlying system where the goal of the defensive response is to preserve critical mission objectives in the presence of adversarial activity. In this paper, a structured approach for modeling aerospace systems is described. The approach includes physical elements, network topology, software applications, system functions, and usage scenarios. We leverage Model-Based Systems Engineering methodology by utilizing the Object Management Group's Systems Modeling Language to represent the system being analyzed and also utilize model transformations to change relevant aspects of the model into specialized analyses. A novel visualization approach is utilized to visualize the entire model as a three-dimensional graph, allowing easier interaction with subject matter experts. The model provides a unifying structure for analyzing the impact of a particular attack or a particular type of attack. Two different example analysis types are demonstrated in this paper: a graph-based propagation analysis based on edge labels, and a graph-based propagation analysis based on node labels.

  16. A Model for the Development of a CDIO Based Curriculum in Electrical Engineering

    DEFF Research Database (Denmark)

    Bruun, Erik; Kjærgaard, Claus

    2011-01-01

    at the Technical University of Denmark and this gives a strong direct impact of the university environment on the resulting curriculum in electrical engineering. The resulting Bachelor of Engineering curriculum is presented and it is discussed how it complies with the model for curriculum development. The main......This paper deals with a model providing a structured method for engineering curriculum design. The model is developed to show the major influencers on the curriculum design and the relations between the influencers. These influencers are identified as the engineering science, the business...... environment, the university environment, and the teachers and students. Each of them and their influence on the curriculum is described and the sources of information about the influencers are discussed. The CDIO syllabus has been defined as part of the basis for the Bachelor of Engineering programs...

  17. Computer-Aided Design Methods for Model-Based Nonlinear Engine Control Systems, Phase I

    Data.gov (United States)

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

  18. Collaborative Model-based Systems Engineering for Cyber-Physical Systems, with a Building Automation Case Study

    DEFF Research Database (Denmark)

    Fitzgerald, John; Gamble, Carl; Payne, Richard

    2016-01-01

    We describe an approach to the model-based engineering of cyber-physical systems that permits the coupling of diverse discrete-event and continuous-time models and their simulators. A case study in the building automation domain demonstrates how such co-models and co-simulation can promote early...

  19. Mean Value Engine Modelling of an SI Engine with EGR

    DEFF Research Database (Denmark)

    Føns, Michael; Müller, Martin; Chevalier, Alain

    1999-01-01

    Mean Value Engine Models (MVEMs) are simplified, dynamic engine models what are physically based. Such models are useful for control studies, for engine control system analysis and for model based engine control systems. Very few published MVEMs have included the effects of Exhaust Gas...... Recirculation (EGR). The purpose of this paper is to present a modified MVEM which includes EGR in a physical way. It has been tested using newly developed, very fast manifold pressure, manifold temperature, port and EGR mass flow sensors. Reasonable agreement has been obtained on an experimental engine...

  20. Engineering of centrifugal dust-collectors based on parallel comparing tests applying computer modelling

    Science.gov (United States)

    Bulygin, Y. I.; Koronchik, D. A.; Abuzyarov, A. A.

    2015-09-01

    Currently researchers are giving serious consideration to studying questions, related to issues of atmosphere protection, in particular, studying of new construction of gas-cleaning SPM cyclonic devices effectivity. Engineering new devices is impossible without applying mathematical model methods, computer modeling and making physical models of studying processes due nature tests.

  1. Adopting Problem-Based Learning Model for AN Electrical Engineering Curriculum

    Science.gov (United States)

    Khan, Mohamed Khan Aftab Ahmed; Sinnadurai, Rajendran; Amudha, M.; Elamvazuthi, I.; Vasant, P.

    2010-06-01

    The shortage of highly qualified academicians in a knowledge-based economy and potential benefits of Problem-Based Learning (PBL) approach has necessitated the adoption of PBL in many areas of education. This paper discusses a PBL experience for an electrical engineering undergraduate course. Some preliminary experiences of implementing them are described and discussed. It was found that PBL approach seem to be an efficient strategy not only for undergraduate engineering education but also for instilling lifelong learning.

  2. A Model-Based Systems Engineering Methodology for Employing Architecture In System Analysis: Developing Simulation Models Using Systems Modeling Language Products to Link Architecture and Analysis

    Science.gov (United States)

    2016-06-01

    Filling Designs for Complex System Simulations.” Ph.D. Dissertation, Naval Postgraduate School. MacCalman, Alex, Hyangshim Kwak, Mary McDonald, and...Michael, Peter Bryant, Mike Wilkinson, Paul King, Ady James, and Stuart Arnold. 2012. “Interpreting ‘Systems Architecting.’” Systems Engineering 15(4...Hyangshim Kwak, Mary McDonald, and Stephen Upton. 2015. “Capturing experimental design insights in support of the model-based systems engineering approach

  3. Using Model-Based Systems Engineering To Provide Artifacts for NASA Project Life-Cycle and Technical Reviews

    Science.gov (United States)

    Parrott, Edith L.; Weiland, Karen J.

    2017-01-01

    The ability of systems engineers to use model-based systems engineering (MBSE) to generate self-consistent, up-to-date systems engineering products for project life-cycle and technical reviews is an important aspect for the continued and accelerated acceptance of MBSE. Currently, many review products are generated using labor-intensive, error-prone approaches based on documents, spreadsheets, and chart sets; a promised benefit of MBSE is that users will experience reductions in inconsistencies and errors. This work examines features of SysML that can be used to generate systems engineering products. Model elements, relationships, tables, and diagrams are identified for a large number of the typical systems engineering artifacts. A SysML system model can contain and generate most systems engineering products to a significant extent and this paper provides a guide on how to use MBSE to generate products for project life-cycle and technical reviews. The use of MBSE can reduce the schedule impact usually experienced for review preparation, as in many cases the review products can be auto-generated directly from the system model. These approaches are useful to systems engineers, project managers, review board members, and other key project stakeholders.

  4. Working towards a scalable model of problem-based learning instruction in undergraduate engineering education

    Science.gov (United States)

    Mantri, Archana

    2014-05-01

    The intent of the study presented in this paper is to show that the model of problem-based learning (PBL) can be made scalable by designing curriculum around a set of open-ended problems (OEPs). The detailed statistical analysis of the data collected to measure the effects of traditional and PBL instructions for three courses in Electronics and Communication Engineering, namely Analog Electronics, Digital Electronics and Pulse, Digital & Switching Circuits is presented here. It measures the effects of pedagogy, gender and cognitive styles on the knowledge, skill and attitude of the students. The study was conducted two times with content designed around same set of OEPs but with two different trained facilitators for all the three courses. The repeatability of results for effects of the independent parameters on dependent parameters is studied and inferences are drawn.

  5. Interface Management for a NASA Flight Project Using Model-Based Systems Engineering (MBSE)

    Science.gov (United States)

    Vipavetz, Kevin; Shull, Thomas A.; Infeld, Samatha; Price, Jim

    2016-01-01

    The goal of interface management is to identify, define, control, and verify interfaces; ensure compatibility; provide an efficient system development; be on time and within budget; while meeting stakeholder requirements. This paper will present a successful seven-step approach to interface management used in several NASA flight projects. The seven-step approach using Model Based Systems Engineering will be illustrated by interface examples from the Materials International Space Station Experiment-X (MISSE-X) project. The MISSE-X was being developed as an International Space Station (ISS) external platform for space environmental studies, designed to advance the technology readiness of materials and devices critical for future space exploration. Emphasis will be given to best practices covering key areas such as interface definition, writing good interface requirements, utilizing interface working groups, developing and controlling interface documents, handling interface agreements, the use of shadow documents, the importance of interface requirement ownership, interface verification, and product transition.

  6. A probabilistic maintenance model for diesel engines

    Science.gov (United States)

    Pathirana, Shan; Abeygunawardane, Saranga Kumudu

    2018-02-01

    In this paper, a probabilistic maintenance model is developed for inspection based preventive maintenance of diesel engines based on the practical model concepts discussed in the literature. Developed model is solved using real data obtained from inspection and maintenance histories of diesel engines and experts' views. Reliability indices and costs were calculated for the present maintenance policy of diesel engines. A sensitivity analysis is conducted to observe the effect of inspection based preventive maintenance on the life cycle cost of diesel engines.

  7. D Modelling and Visualization Based on the Unity Game Engine - Advantages and Challenges

    Science.gov (United States)

    Buyuksalih, I.; Bayburt, S.; Buyuksalih, G.; Baskaraca, A. P.; Karim, H.; Rahman, A. A.

    2017-11-01

    3D City modelling is increasingly popular and becoming valuable tools in managing big cities. Urban and energy planning, landscape, noise-sewage modelling, underground mapping and navigation are among the applications/fields which really depend on 3D modelling for their effectiveness operations. Several research areas and implementation projects had been carried out to provide the most reliable 3D data format for sharing and functionalities as well as visualization platform and analysis. For instance, BIMTAS company has recently completed a project to estimate potential solar energy on 3D buildings for the whole Istanbul and now focussing on 3D utility underground mapping for a pilot case study. The research and implementation standard on 3D City Model domain (3D data sharing and visualization schema) is based on CityGML schema version 2.0. However, there are some limitations and issues in implementation phase for large dataset. Most of the limitations were due to the visualization, database integration and analysis platform (Unity3D game engine) as highlighted in this paper.

  8. 3D MODELLING AND VISUALIZATION BASED ON THE UNITY GAME ENGINE – ADVANTAGES AND CHALLENGES

    Directory of Open Access Journals (Sweden)

    I. Buyuksalih

    2017-11-01

    Full Text Available 3D City modelling is increasingly popular and becoming valuable tools in managing big cities. Urban and energy planning, landscape, noise-sewage modelling, underground mapping and navigation are among the applications/fields which really depend on 3D modelling for their effectiveness operations. Several research areas and implementation projects had been carried out to provide the most reliable 3D data format for sharing and functionalities as well as visualization platform and analysis. For instance, BIMTAS company has recently completed a project to estimate potential solar energy on 3D buildings for the whole Istanbul and now focussing on 3D utility underground mapping for a pilot case study. The research and implementation standard on 3D City Model domain (3D data sharing and visualization schema is based on CityGML schema version 2.0. However, there are some limitations and issues in implementation phase for large dataset. Most of the limitations were due to the visualization, database integration and analysis platform (Unity3D game engine as highlighted in this paper.

  9. Towards Continuous Integration in Model-Based Engineering of Automated Production Systems

    OpenAIRE

    Jakob Mund, Iman Badr, Safa Bougouffa, Birgit Vogel-Heuser

    2017-01-01

    Continuous integration (CI) is widely used in software engineering. The observed benefits include reduced efforts for system integration, which is particularly appealing for engineering automated production systems (aPS) due to the different disciplines involved. Yet, while many individual quality assurance means for aPS have been proposed, their adequacy for and systematic use in CI remains unclear. In this article, we provide two key contributions: First, we propose a quality model for mode...

  10. The development of performance-based practical assessment model at civil engineering workshop in state polytechnic

    Science.gov (United States)

    Kristinayanti, W. S.; Mas Pertiwi, I. G. A. I.; Evin Yudhi, S.; Lokantara, W. D.

    2018-01-01

    Assessment is an important element in education that shall oversees students’ competence not only in terms of cognitive aspect, but alsothe students’ psychomotorin a comprehensive way. Civil Engineering Department at Bali State Polytechnic,as a vocational education institution, emphasizes on not only the theoretical foundation of the study, but also the application throughpracticum in workshop-based learning. We are aware of a need for performance-based assessment for these students, which would be essential for the student’s all-round performance in their studies.We try to develop a performance-based practicum assessment model that is needed to assess student’s ability in workshop-based learning. This research was conducted in three stages, 1) learning needs analysis, 2) instruments development, and 3) testing of instruments. The study uses rubrics set-up to test students’ competence in the workshop and test the validity. We obtained 34-point valid statement out of 35, and resulted in value of Cronbach’s alpha equal to 0.977. In expert test we obtained a value of CVI = 0.75 which means that the drafted assessment is empirically valid within thetrial group.

  11. Agent-based re-engineering of ErbB signaling: a modeling pipeline for integrative systems biology.

    Science.gov (United States)

    Das, Arya A; Ajayakumar Darsana, T; Jacob, Elizabeth

    2017-03-01

    Experiments in systems biology are generally supported by a computational model which quantitatively estimates the parameters of the system by finding the best fit to the experiment. Mathematical models have proved to be successful in reverse engineering the system. The data generated is interpreted to understand the dynamics of the underlying phenomena. The question we have sought to answer is that - is it possible to use an agent-based approach to re-engineer a biological process, making use of the available knowledge from experimental and modelling efforts? Can the bottom-up approach benefit from the top-down exercise so as to create an integrated modelling formalism for systems biology? We propose a modelling pipeline that learns from the data given by reverse engineering, and uses it for re-engineering the system, to carry out in-silico experiments. A mathematical model that quantitatively predicts co-expression of EGFR-HER2 receptors in activation and trafficking has been taken for this study. The pipeline architecture takes cues from the population model that gives the rates of biochemical reactions, to formulate knowledge-based rules for the particle model. Agent-based simulations using these rules, support the existing facts on EGFR-HER2 dynamics. We conclude that, re-engineering models, built using the results of reverse engineering, opens up the possibility of harnessing the power pack of data which now lies scattered in literature. Virtual experiments could then become more realistic when empowered with the findings of empirical cell biology and modelling studies. Implemented on the Agent Modelling Framework developed in-house. C ++ code templates available in Supplementary material . liz.csir@gmail.com. Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

  12. Model-Based Control of a Nonlinear Aircraft Engine Simulation using an Optimal Tuner Kalman Filter Approach

    Science.gov (United States)

    Connolly, Joseph W.; Csank, Jeffrey Thomas; Chicatelli, Amy; Kilver, Jacob

    2013-01-01

    This paper covers the development of a model-based engine control (MBEC) methodology featuring a self tuning on-board model applied to an aircraft turbofan engine simulation. Here, the Commercial Modular Aero-Propulsion System Simulation 40,000 (CMAPSS40k) serves as the MBEC application engine. CMAPSS40k is capable of modeling realistic engine performance, allowing for a verification of the MBEC over a wide range of operating points. The on-board model is a piece-wise linear model derived from CMAPSS40k and updated 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. Investigations using the MBEC to provide a stall margin limit for the controller protection logic are presented that could provide benefits over a simple acceleration schedule that is currently used in traditional engine control architectures.

  13. Use of DXA-Based Structural Engineering Models of the Proximal Femur to Discriminate Hip Fracture

    Science.gov (United States)

    Yang, Lang; Peel, Nicola; Clowes, Jackie A; McCloskey, Eugene V; Eastell, Richard

    2011-01-01

    Several DXA-based structural engineering models (SEMs) of the proximal femur have been developed to estimate stress caused by sideway falls. Their usefulness in discriminating hip fracture has not yet been established and we therefore evaluated these models. The hip DXA scans of 51 postmenopausal women with hip fracture (30 femoral neck, 17 trochanteric, and 4 unspecified) and 153 age-, height-, and weight-matched controls were reanalyzed using a special version of Hologic’s software that produced a pixel-by-pixel BMD map. For each map, a curved-beam, a curved composite-beam, and a finite element model were generated to calculate stress within the bone when falling sideways. An index of fracture risk (IFR) was defined over the femoral neck, trochanter, and total hip as the stress divided by the yield stress at each pixel and averaged over the regions of interest. Hip structure analysis (HSA) was also performed using Hologic APEX analysis software. Hip BMD and almost all parameters derived from HSA and SEM were discriminators of hip fracture on their own because their ORs were significantly >1. Because of the high correlation of total hip BMD to HSA and SEM-derived parameters, only the bone width discriminated hip fracture independently from total hip BMD. Judged by the area under the receiver operating characteristics curve, the trochanteric IFR derived from the finite element model was significant better than total hip BMD alone and similar to the total hip BMD plus bone width in discriminating all hip fracture and femoral neck fracture. No index was better than total hip BMD for discriminating trochanteric fractures. In conclusion, the finite element model has the potential to replace hip BMD in discriminating hip fractures. PMID:18767924

  14. Application for managing model-based material properties for simulation-based engineering

    Science.gov (United States)

    Hoffman, Edward L [Alameda, CA

    2009-03-03

    An application for generating a property set associated with a constitutive model of a material includes a first program module adapted to receive test data associated with the material and to extract loading conditions from the test data. A material model driver is adapted to receive the loading conditions and a property set and operable in response to the loading conditions and the property set to generate a model response for the material. A numerical optimization module is adapted to receive the test data and the model response and operable in response to the test data and the model response to generate the property set.

  15. Implementation of a Goal-Based Systems Engineering Process Using the Systems Modeling Language (SysML)

    Science.gov (United States)

    Breckenridge, Jonathan T.; Johnson, Stephen B.

    2013-01-01

    Building upon the purpose, theoretical approach, and use of a Goal-Function Tree (GFT) being presented by Dr. Stephen B. Johnson, described in a related Infotech 2013 ISHM abstract titled "Goal-Function Tree Modeling for Systems Engineering and Fault Management", this paper will describe the core framework used to implement the GFTbased systems engineering process using the Systems Modeling Language (SysML). These two papers are ideally accepted and presented together in the same Infotech session. Statement of problem: SysML, as a tool, is currently not capable of implementing the theoretical approach described within the "Goal-Function Tree Modeling for Systems Engineering and Fault Management" paper cited above. More generally, SysML's current capabilities to model functional decompositions in the rigorous manner required in the GFT approach are limited. The GFT is a new Model-Based Systems Engineering (MBSE) approach to the development of goals and requirements, functions, and its linkage to design. As a growing standard for systems engineering, it is important to develop methods to implement GFT in SysML. Proposed Method of Solution: Many of the central concepts of the SysML language are needed to implement a GFT for large complex systems. In the implementation of those central concepts, the following will be described in detail: changes to the nominal SysML process, model view definitions and examples, diagram definitions and examples, and detailed SysML construct and stereotype definitions.

  16. PBL-SEE: An Authentic Assessment Model for PBL-Based Software Engineering Education

    Science.gov (United States)

    dos Santos, Simone C.

    2017-01-01

    The problem-based learning (PBL) approach has been successfully applied to teaching software engineering thanks to its principles of group work, learning by solving real problems, and learning environments that match the market realities. However, the lack of well-defined methodologies and processes for implementing the PBL approach represents a…

  17. Developing a blended learning based model for teaching foreign languages in engineering institutions

    Directory of Open Access Journals (Sweden)

    Kudryashova Alexandra V.

    2016-01-01

    Full Text Available The present paper deals with studying theoretical and methodical background of the concept of blended learning, which is the major didactic tool of the modern methods of foreign languages teaching. It also considers the principles of integrating blended learning in teaching foreign languages in engineering institutions. The basics of pedagogical modelling used for developing a model of integrating blended learning in the foreign language teaching are defined. The schematic model representation is given and the way of implementing the described model into the educational process is shown via the example of the lesson on “Cohesive devices”.

  18. Reliability growth modeling analysis of the space shuttle main engines based upon the Weibull process

    Science.gov (United States)

    Wheeler, J. T.

    1990-01-01

    The Weibull process, identified as the inhomogeneous Poisson process with the Weibull intensity function, is used to model the reliability growth assessment of the space shuttle main engine test and flight failure data. Additional tables of percentage-point probabilities for several different values of the confidence coefficient have been generated for setting (1-alpha)100-percent two sided confidence interval estimates on the mean time between failures. The tabled data pertain to two cases: (1) time-terminated testing, and (2) failure-terminated testing. The critical values of the three test statistics, namely Cramer-von Mises, Kolmogorov-Smirnov, and chi-square, were calculated and tabled for use in the goodness of fit tests for the engine reliability data. Numerical results are presented for five different groupings of the engine data that reflect the actual response to the failures.

  19. Studies on combined model based on functional objectives of large scale complex engineering

    Science.gov (United States)

    Yuting, Wang; Jingchun, Feng; Jiabao, Sun

    2018-03-01

    As various functions were included in large scale complex engineering, and each function would be conducted with completion of one or more projects, combined projects affecting their functions should be located. Based on the types of project portfolio, the relationship of projects and their functional objectives were analyzed. On that premise, portfolio projects-technics based on their functional objectives were introduced, then we studied and raised the principles of portfolio projects-technics based on the functional objectives of projects. In addition, The processes of combined projects were also constructed. With the help of portfolio projects-technics based on the functional objectives of projects, our research findings laid a good foundation for management of large scale complex engineering portfolio management.

  20. Streaming Model Based Volume Ray Casting Implementation for Cell Broadband Engine

    Directory of Open Access Journals (Sweden)

    Jusub Kim

    2009-01-01

    Full Text Available Interactive high quality volume rendering is becoming increasingly more important as the amount of more complex volumetric data steadily grows. While a number of volumetric rendering techniques have been widely used, ray casting has been recognized as an effective approach for generating high quality visualization. However, for most users, the use of ray casting has been limited to datasets that are very small because of its high demands on computational power and memory bandwidth. However the recent introduction of the Cell Broadband Engine (Cell B.E. processor, which consists of 9 heterogeneous cores designed to handle extremely demanding computations with large streams of data, provides an opportunity to put the ray casting into practical use. In this paper, we introduce an efficient parallel implementation of volume ray casting on the Cell B.E. The implementation is designed to take full advantage of the computational power and memory bandwidth of the Cell B.E. using an intricate orchestration of the ray casting computation on the available heterogeneous resources. Specifically, we introduce streaming model based schemes and techniques to efficiently implement acceleration techniques for ray casting on Cell B.E. In addition to ensuring effective SIMD utilization, our method provides two key benefits: there is no cost for empty space skipping and there is no memory bottleneck on moving volumetric data for processing. Our experimental results show that we can interactively render practical datasets on a single Cell B.E. processor.

  1. Surface modeling method for aircraft engine blades by using speckle patterns based on the virtual stereo vision system

    Science.gov (United States)

    Yu, Zhijing; Ma, Kai; Wang, Zhijun; Wu, Jun; Wang, Tao; Zhuge, Jingchang

    2018-03-01

    A blade is one of the most important components of an aircraft engine. Due to its high manufacturing costs, it is indispensable to come up with methods for repairing damaged blades. In order to obtain a surface model of the blades, this paper proposes a modeling method by using speckle patterns based on the virtual stereo vision system. Firstly, blades are sprayed evenly creating random speckle patterns and point clouds from blade surfaces can be calculated by using speckle patterns based on the virtual stereo vision system. Secondly, boundary points are obtained in the way of varied step lengths according to curvature and are fitted to get a blade surface envelope with a cubic B-spline curve. Finally, the surface model of blades is established with the envelope curves and the point clouds. Experimental results show that the surface model of aircraft engine blades is fair and accurate.

  2. A collagen based vitro model of angiogenesis designed for tissue-engineering material

    Science.gov (United States)

    Feng, Ting; Chen, Yuanwei; Shi, Guoqi; Yu, Xixun; Wan, Changxiu

    2008-11-01

    Angiogenesis is central importance to tissue-engineering. Many vitro models are developed to study the mechanism of angiogenesis, making a great deal of contribution to drug development against tumor, and often may be expensive, time-consuming. Till now, few reported models have been applied to evaluating the effect of degradation fluid of tissue-engineering material to angiogenesis. In present study, we used ECV304 cell as the model cell line, type I collagen matrix that contained no stimulatory factors as a culture substratum to develop a testing model. Tube-like structure (TLS) formed within 8 h on lower density of collagen (0.2, 0.5 mg/ml), which is not found on dense collagen (1, 2 mg/ml). After ECV304 cells were seeded on the surface of collagen matrix, adherence occurred within 1 h. Soon afterwards, ECV304 cells migrated into cell aggregates, then sent out elongated cell processes to form TLS by cytoplasmic anastomosis. Proliferation was obviously perceived during the course. To investigate the efficiency of the model, we took poly(lactic acid) (PLA) degradation fluid with degradation time varying from 1 to 120 days as the testing material. TLS formation is enhanced by ECV304 cells exposed to early degradation fluid before 50-day point, and the trend of inhibition grew as the degradation time increased. Further, no formation was found in degradation fluid after 90-day point. The model is sensitive to the surrounding environment, and can demonstrate the effects of testing material quantitatively to angiogenesis. In summary, the simplicity, reproducibility and miniaturized character of the model described here may make it highly useful as a medium to test the effect of degradation fluid of tissue-engineering material to angiogenesis.

  3. A proposal of ecologic taxes based on thermo-economic performance of heat engine models

    Energy Technology Data Exchange (ETDEWEB)

    Barranco-Jimenez, M. A. [Departamento de Ciencias Basicas, Escuela Superior de Computo del IPN, Av. Miguel Bernal Esq. Juan de Dios Batiz U.P. Zacatenco CP 07738, D.F. (Mexico); Ramos-Gayosso, I. [Unidad de Administracion de Riesgos, Banco de Mexico, 5 de Mayo, Centro, D.F. (Mexico); Rosales, M. A. [Departamento de Fisica y Matematicas, Universidad de las Americas, Puebla Exhacienda Sta. Catarina Martir, Cholula 72820, Puebla (Mexico); Angulo-Brown, F. [Departamento de Fisica, Escuela Superior de Fisica y Matematicas del IPN, Edif. 9 U.P. Zacatenco CP 07738, D.F. (Mexico)

    2009-07-01

    Within the context of Finite-Time Thermodynamics (FTT) a simplified thermal power plant model (the so-called Novikov engine) is analyzed under economical criteria by means of the concepts of profit function and the costs involved in the performance of the power plant. In this study, two different heat transfer laws are used, the so called Newton's law of cooling and the Dulong-Petit's law of cooling. Two FTT optimization criteria for the performance analysis are used: the maximum power regime (MP) and the so-called ecological criterion. This last criterion leads the engine model towards a mode of performance that appreciably diminishes the engine's wasted energy. In this work, it is shown that the energy-unit price produced under maximum power conditions is cheaper than that produced under maximum ecological (ME) conditions. This was accomplished by using a typical definition of profits function stemming from economics. The MP-regime produces considerably more wasted energy toward the environment, thus the MP energy-unit price is subsidized by nature. Due to this fact, an ecological tax is proposed, which could be a certain function of the price difference between the MP and ME modes of power production. (author)

  4. Connecting Requirements to Architecture and Analysis via Model-Based Systems Engineering

    Science.gov (United States)

    Cole, Bjorn F.; Jenkins, J. Steven

    2015-01-01

    In traditional systems engineering practice, architecture, concept development, and requirements development are related but still separate activities. Concepts for operation, key technical approaches, and related proofs of concept are developed. These inform the formulation of an architecture at multiple levels, starting with the overall system composition and functionality and progressing into more detail. As this formulation is done, a parallel activity develops a set of English statements that constrain solutions. These requirements are often called "shall statements" since they are formulated to use "shall." The separation of requirements from design is exacerbated by well-meaning tools like the Dynamic Object-Oriented Requirements System (DOORS) that remained separated from engineering design tools. With the Europa Clipper project, efforts are being taken to change the requirements development approach from a separate activity to one intimately embedded in formulation effort. This paper presents a modeling approach and related tooling to generate English requirement statements from constraints embedded in architecture definition.

  5. Implementation of a model based fault detection and diagnosis for actuation faults of the Space Shuttle main engine

    Science.gov (United States)

    Duyar, A.; Guo, T.-H.; Merrill, W.; Musgrave, J.

    1992-01-01

    In a previous study, Guo, Merrill and Duyar, 1990, reported a conceptual development of a fault detection and diagnosis system for actuation faults of the space shuttle main engine. This study, which is a continuation of the previous work, implements the developed fault detection and diagnosis scheme for the real time actuation fault diagnosis of the space shuttle main engine. The scheme will be used as an integral part of an intelligent control system demonstration experiment at NASA Lewis. The diagnosis system utilizes a model based method with real time identification and hypothesis testing for actuation, sensor, and performance degradation faults.

  6. Final Report for NFE-07-00912: Development of Model Fuels Experimental Engine Data Base & Kinetic Modeling Parameter Sets

    Energy Technology Data Exchange (ETDEWEB)

    Bunting, Bruce G [ORNL

    2012-10-01

    The automotive and engine industries are in a period of very rapid change being driven by new emission standards, new types of after treatment, new combustion strategies, the introduction of new fuels, and drive for increased fuel economy and efficiency. The rapid pace of these changes has put more pressure on the need for modeling of engine combustion and performance, in order to shorten product design and introduction cycles. New combustion strategies include homogeneous charge compression ignition (HCCI), partial-premixed combustion compression ignition (PCCI), and dilute low temperature combustion which are being developed for lower emissions and improved fuel economy. New fuels include bio-fuels such as ethanol or bio-diesel, drop-in bio-derived fuels and those derived from new crude oil sources such as gas-to-liquids, coal-to-liquids, oil sands, oil shale, and wet natural gas. Kinetic modeling of the combustion process for these new combustion regimes and fuels is necessary in order to allow modeling and performance assessment for engine design purposes. In this research covered by this CRADA, ORNL developed and supplied experimental data related to engine performance with new fuels and new combustion strategies along with interpretation and analysis of such data and consulting to Reaction Design, Inc. (RD). RD performed additional analysis of this data in order to extract important parameters and to confirm engine and kinetic models. The data generated was generally published to make it available to the engine and automotive design communities and also to the Reaction Design Model Fuels Consortium (MFC).

  7. Engineering and Modeling Carbon Nanofiller-Based Scaffolds for Tissue Regeneration

    Science.gov (United States)

    Al Habis, Nuha Hamad

    Conductive biopolymers are starting to emerge as potential scaffolds of the future. These scaffolds exhibit some unique properties such as inherent conductivity, mechanical and surface properties. Traditionally, a conjugated polymer is used to constitute a conductive network. An alternative method currently being used is nanofillers as additives in the polymer. In this dissertation, we fabricated an intelligent scaffold for use in tissue engineering applications. The main idea was to enhance the mechanical, electrical properties and cell growth of scaffolds by using distinct types of nanofillers such as graphene, carbon nanofiber and carbon black. We identified the optimal concentrations of nano-additive in both fibrous and film scaffolds to obtain the highest mechanical and electrical properties without neglecting any of them. Lastly, we investigated the performance of these scaffold with cell biology. To accomplish these tasks, we first studied the mechanical properties of the scaffold as a function of morphology, concentration and variety of carbon nanofillers. Results showed that there was a gradual increase of the modulus and the fracture strength while using carbon black, carbon nanofiber and graphene, due to the small and strong carbon-to-carbon bonds and the length of the interlayer spacing. Moreover, regardless of the fabrication method, there was an increase in mechanical properties as the concentration of nanofillers increased until a threshold of 7 wt% was reached for the nanofiller film scaffold and 1%wt for the fibrous scaffold. Experimental results of carbon black exhibited a good agreement when compared with data obtained using numerical approaches and analytical models, especially in the case of lower carbon black fractions. Second, we examined the influence of electrical properties of nanofillers based on the concentration and the geometry of carbon nanofillers in the polymer matrix using experimental and numerical simulation approaches. The

  8. A dislocation-based crystal viscoplasticity model with application to micro-engineered plasma-facing materials

    International Nuclear Information System (INIS)

    Rivera, David; Huang, Yue; Po, Giacomo; Ghoniem, Nasr M.

    2017-01-01

    Materials developed with special surface architecture are shown here to be more resilient to the transient thermomechanical environments imposed by intermittent exposures to high heat flux thermal loading typical of long-pulse plasma transients. In an accompanying article, we present experimental results that show the relaxation of residual thermal stresses in micro-engineered W surfaces. A dislocation-based model is extended here within the framework of large deformation crystal plasticity. The model is applied to the deformation of single crystals, polycrystals, and micro-engineered surfaces composed of a uniform density of micro-pillars. The model is utilized to design tapered surface micro-pillar architecture, composed of a Re core and W coatings. Residual stresses generated by cyclic thermomechanical loading of these architectures show that the surface can be in a compressive stress state, following a short shakedown plasma exposure, thus mitigating surface fracture. - • Materials developed with special surface architecture are shown to be more resilient to the transient thermomechanical plasma transients. • A dislocation-based model is extended within the framework of large deformation crystal plasticity. • The model is applied to the deformation of single crystals, polycrystals, and micro-engineered surfaces. • The model is utilized to design tapered surface micro-pillar architecture, composed of a Re core and W coatings. • Residual stresses generated by cyclic thermomechanical loading show that the surface can be in a compressive stress state, thus mitigating surface fracture.

  9. Development of a Model-Based Systems Engineering Application for the Ground Vehicle Robotics Sustainment Industrial Base

    Science.gov (United States)

    2013-02-04

    symbols, human perceptual processing, human eye properties, visual attention, the Gestalt laws of pattern perception, visual objects perception...visual grammars like Systems Modeling Language (SysML), are considered to be applications of Gestalt laws. Specialized software available in the market... psychological inertia (PI) associated with engineers stepping outside their background to observe useful patterns. The authors deemed that aligning the 39

  10. Model-Based Systems Engineering for Capturing Mission Architecture System Processes with an Application Case Study - Orion Flight Test 1

    Science.gov (United States)

    Bonanne, Kevin H.

    2011-01-01

    Model-based Systems Engineering (MBSE) is an emerging methodology that can be leveraged to enhance many system development processes. MBSE allows for the centralization of an architecture description that would otherwise be stored in various locations and formats, thus simplifying communication among the project stakeholders, inducing commonality in representation, and expediting report generation. This paper outlines the MBSE approach taken to capture the processes of two different, but related, architectures by employing the Systems Modeling Language (SysML) as a standard for architecture description and the modeling tool MagicDraw. The overarching goal of this study was to demonstrate the effectiveness of MBSE as a means of capturing and designing a mission systems architecture. The first portion of the project focused on capturing the necessary system engineering activities that occur when designing, developing, and deploying a mission systems architecture for a space mission. The second part applies activities from the first to an application problem - the system engineering of the Orion Flight Test 1 (OFT-1) End-to-End Information System (EEIS). By modeling the activities required to create a space mission architecture and then implementing those activities in an application problem, the utility of MBSE as an approach to systems engineering can be demonstrated.

  11. In vivo remodeling and structural characterization of fibrin-based tissue-engineered heart valves in the adult sheep model.

    Science.gov (United States)

    Flanagan, Thomas C; Sachweh, Jörg S; Frese, Julia; Schnöring, Heike; Gronloh, Nina; Koch, Sabine; Tolba, Rene H; Schmitz-Rode, Thomas; Jockenhoevel, Stefan

    2009-10-01

    Autologous fibrin-based tissue-engineered heart valves have demonstrated excellent potential as patient-derived valve replacements. The present pilot study aims to evaluate the structure and mechanical durability of fibrin-based heart valves after implantation in a large-animal model (sheep). Tissue-engineered heart valves were molded using a fibrin scaffold and autologous arterial-derived cells before 28 days of mechanical conditioning. Conditioned valves were subsequently implanted in the pulmonary trunk of the same animals from which the cells were harvested. After 3 months in vivo, explanted valve conduits (n = 4) had remained intact and exhibited native tissue consistency, although leaflets demonstrated insufficiency because of tissue contraction. Routine histology showed remarkable tissue development and cell distribution, along with functional blood vessel ingrowth. A confluent monolayer of endothelial cells was present on the valve surface, as evidenced by scanning electron microscopy and positive von Willebrand factor staining. Immunohistochemistry and extracellular matrix (ECM) assay demonstrated complete resorption of the fibrin scaffold and replacement with ECM proteins. Transmission electron microscopy revealed mature collagen formation and viable, active resident tissue cells. The preliminary findings of implanted fibrin-based tissue-engineered heart valves are encouraging, with excellent tissue remodeling and structural durability after 3 months in vivo. The results from this pilot study highlight the potential for construction of completely "autologous" customized tissue-engineered heart valves based on a patient-derived fibrin scaffold.

  12. A Proposal of Ecologic Taxes Based on Thermo-Economic Performance of Heat Engine Models

    Directory of Open Access Journals (Sweden)

    Fernando Angulo-Brown

    2009-11-01

    Full Text Available Within the context of Finite-Time Thermodynamics (FTT a simplified thermal power plant model (the so-called Novikov engine is analyzed under economical criteria by means of the concepts of profit function and the costs involved in the performance of the power plant. In this study, two different heat transfer laws are used, the so called Newton’s law of cooling and the Dulong-Petit’s law of cooling. Two FTT optimization criteria for the performance analysis are used: the maximum power regime (MP and the so-called ecological criterion. This last criterion leads the engine model towards a mode of performance that appreciably diminishes the engine’s wasted energy. In this work, it is shown that the energy-unit price produced under maximum power conditions is cheaper than that produced under maximum ecological (ME conditions. This was accomplished by using a typical definition of profits function stemming from economics. The MP-regime produces considerably more wasted energy toward the environment, thus the MP energy-unit price is subsidized by nature. Due to this fact, an ecological tax is proposed, which could be a certain function of the price difference between the MP and ME modes of power production.

  13. Introduction to Information Visualization (InfoVis) Techniques for Model-Based Systems Engineering

    Science.gov (United States)

    Sindiy, Oleg; Litomisky, Krystof; Davidoff, Scott; Dekens, Frank

    2013-01-01

    This paper presents insights that conform to numerous system modeling languages/representation standards. The insights are drawn from best practices of Information Visualization as applied to aerospace-based applications.

  14. A model-based approach to associate complexity and robustness in engineering systems

    DEFF Research Database (Denmark)

    Göhler, Simon Moritz; D. Frey, Daniel; Howard, Thomas J.

    2017-01-01

    Ever increasing functionality and complexity of products and systems challenge development companies in achieving high and consistent quality. A model-based approach is used to investigate the relationship between system complexity and system robustness. The measure for complexity is based...

  15. A development process meta-model for Web based expert systems: The Web engineering point of view

    DEFF Research Database (Denmark)

    Dokas, I.M.; Alapetite, Alexandre

    2006-01-01

    Similar to many legacy computer systems, expert systems can be accessed via the Web, forming a set of Web applications known as Web based expert systems. The tough Web competition, the way people and organizations rely on Web applications and theincreasing user requirements for better services have...... raised their complexity. Unfortunately, there is so far no clear answer to the question: How may the methods and experience of Web engineering and expert systems be combined and applied in order todevelop effective and successful Web based expert systems? In an attempt to answer this question......, a development process meta-model for Web based expert systems will be presented. Based on this meta-model, a publicly available Web based expert systemcalled Landfill Operation Management Advisor (LOMA) was developed. In addition, the results of an accessibility evaluation on LOMA – the first ever reported...

  16. Model-based system-of-systems engineering for space-based command, control, communication, and information architecture design

    Science.gov (United States)

    Sindiy, Oleg V.

    This dissertation presents a model-based system-of-systems engineering (SoSE) approach as a design philosophy for architecting in system-of-systems (SoS) problems. SoS refers to a special class of systems in which numerous systems with operational and managerial independence interact to generate new capabilities that satisfy societal needs. Design decisions are more complicated in a SoS setting. A revised Process Model for SoSE is presented to support three phases in SoS architecting: defining the scope of the design problem, abstracting key descriptors and their interrelations in a conceptual model, and implementing computer-based simulations for architectural analyses. The Process Model enables improved decision support considering multiple SoS features and develops computational models capable of highlighting configurations of organizational, policy, financial, operational, and/or technical features. Further, processes for verification and validation of SoS models and simulations are also important due to potential impact on critical decision-making and, thus, are addressed. Two research questions frame the research efforts described in this dissertation. The first concerns how the four key sources of SoS complexity---heterogeneity of systems, connectivity structure, multi-layer interactions, and the evolutionary nature---influence the formulation of SoS models and simulations, trade space, and solution performance and structure evaluation metrics. The second question pertains to the implementation of SoSE architecting processes to inform decision-making for a subset of SoS problems concerning the design of information exchange services in space-based operations domain. These questions motivate and guide the dissertation's contributions. A formal methodology for drawing relationships within a multi-dimensional trade space, forming simulation case studies from applications of candidate architecture solutions to a campaign of notional mission use cases, and

  17. 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.

  18. Development of an Organizational Effectiveness Model for Base Level Civil Engineering Organizations.

    Science.gov (United States)

    1983-09-01

    known as content analysis ( Kohlhaas & Williams, 1980) to create a functional model to define organizational effec- tiveness within base level civil...fresearcher) reliability of this technique is quite respectable. ( Kohlhaas & Williams, 1980, p. 34) For the purposes of this research effort, the grouping...ing management graduate students of the School of Systems and Logistics, AFIT, Wright-Patterson Air Force Base, Oh., November 5, 198 2. Kohlhaas

  19. Studies and analyses of the space shuttle main engine. Failure information propagation model data base and software

    Science.gov (United States)

    Tischer, A. E.

    1987-01-01

    The failure information propagation model (FIPM) data base was developed to store and manipulate the large amount of information anticipated for the various Space Shuttle Main Engine (SSME) FIPMs. The organization and structure of the FIPM data base is described, including a summary of the data fields and key attributes associated with each FIPM data file. The menu-driven software developed to facilitate and control the entry, modification, and listing of data base records is also discussed. The transfer of the FIPM data base and software to the NASA Marshall Space Flight Center is described. Complete listings of all of the data base definition commands and software procedures are included in the appendixes.

  20. Usage of Parameterized Fatigue Spectra and Physics-Based Systems Engineering Models for Wind Turbine Component Sizing: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Parsons, Taylor; Guo, Yi; Veers, Paul; Dykes, Katherine; Damiani, Rick

    2016-01-26

    Software models that use design-level input variables and physics-based engineering analysis for estimating the mass and geometrical properties of components in large-scale machinery can be very useful for analyzing design trade-offs in complex systems. This study uses DriveSE, an OpenMDAO-based drivetrain model that uses stress and deflection criteria to size drivetrain components within a geared, upwind wind turbine. Because a full lifetime fatigue load spectrum can only be defined using computationally-expensive simulations in programs such as FAST, a parameterized fatigue loads spectrum that depends on wind conditions, rotor diameter, and turbine design life has been implemented. The parameterized fatigue spectrum is only used in this paper to demonstrate the proposed fatigue analysis approach. This paper details a three-part investigation of the parameterized approach and a comparison of the DriveSE model with and without fatigue analysis on the main shaft system. It compares loads from three turbines of varying size and determines if and when fatigue governs drivetrain sizing compared to extreme load-driven design. It also investigates the model's sensitivity to shaft material parameters. The intent of this paper is to demonstrate how fatigue considerations in addition to extreme loads can be brought into a system engineering optimization.

  1. A Curriculum Model: Engineering Design Graphics Course Updates Based on Industrial and Academic Institution Requirements

    Science.gov (United States)

    Meznarich, R. A.; Shava, R. C.; Lightner, S. L.

    2009-01-01

    Engineering design graphics courses taught in colleges or universities should provide and equip students preparing for employment with the basic occupational graphics skill competences required by engineering and technology disciplines. Academic institutions should introduce and include topics that cover the newer and more efficient graphics…

  2. A Web-based modeling tool for the SEMAT Essence theory of software engineering

    Directory of Open Access Journals (Sweden)

    Daniel Graziotin

    2013-09-01

    Full Text Available As opposed to more mature subjects, software engineering lacks general theories that establish its foundations as a discipline. The Essence Theory of software engineering (Essence has been proposed by the Software Engineering Methods and Theory (SEMAT initiative. The goal of Essence is to develop a theoretically sound basis for software engineering practice and its wide adoption. However, Essence is far from reaching academic- and industry-wide adoption. The reasons for this include a struggle to foresee its utilization potential and a lack of tools for implementation. SEMAT Accelerator (SematAcc is a Web-positioning tool for a software engineering endeavor, which implements the SEMAT’s Essence kernel. SematAcc permits the use of Essence, thus helping to understand it. The tool enables the teaching, adoption, and research of Essence in controlled experiments and case studies.

  3. Transforming Systems Engineering through Model Centric Engineering

    Science.gov (United States)

    2017-08-08

    for Creative Technologies ( ICT ). Section 5 describes research into the use of mission and system modeling and simulation, and its relationships to...be used in MDAO (UC03).  The metamodel provided by ICT represents information and metrics captured while observing the users of the gaming...Engineering Simulation MDAO 4.2 GRAPHICAL CONOPS (USC ICT – RICHMOND VIEW) The USC Institute for Creative Technologies ( ICT ) will support this use

  4. An Analysis of Organizational Commitment among Base Level Civilian Engineers in Air Force Civil Engineering.

    Science.gov (United States)

    Services will significantly influence organizational commitment and turnover among civilian engineers in the base level Civil Engineering organization. A...model of organizational commitment was developed and tested to determine the significant factors that contribute to commitment among civilian engineers...results confirmed previous research on organizational commitment among engineers. Engineers were found to value the intrinsic aspects of their job more than

  5. An Arts-Based Instructional Model for Student Creativity in Engineering Design

    OpenAIRE

    Brian Laduca; Adrienne Ausdenmoore; Jen Katz-Buonincontro; Kevin Patrick Hallinan; Karlos Marshall

    2017-01-01

    Over the past twenty years, nearly all job growth in the United States has emerged from new companies and organizations with assumedly innovative products, services, and practices. Yet, the nurturing of student creative thinking and problem solving is infrequent in engineering education. Inherent to developing these creativity skills and attributes is the need to be exposed to difference — in people and environment. Engineering education rarely offers such opportunities. Additionally, enginee...

  6. Reverse engineering a social agent-based hidden markov model--visage.

    Science.gov (United States)

    Chen, Hung-Ching Justin; Goldberg, Mark; Magdon-Ismail, Malik; Wallace, William A

    2008-12-01

    We present a machine learning approach to discover the agent dynamics that drives the evolution of the social groups in a community. We set up the problem by introducing an agent-based hidden Markov model for the agent dynamics: an agent's actions are determined by micro-laws. Nonetheless, We learn the agent dynamics from the observed communications without knowing state transitions. Our approach is to identify the appropriate micro-laws corresponding to an identification of the appropriate parameters in the model. The model identification problem is then formulated as a mixed optimization problem. To solve the problem, we develop a multistage learning process for determining the group structure, the group evolution, and the micro-laws of a community based on the observed set of communications among actors, without knowing the semantic contents. Finally, to test the quality of our approximations and the feasibility of the approach, we present the results of extensive experiments on synthetic data as well as the results on real communities, such as Enron email and Movie newsgroups. Insight into agent dynamics helps us understand the driving forces behind social evolution.

  7. Model-based design of bistable cell factories for metabolic engineering.

    Science.gov (United States)

    Srinivasan, Shyam; Cluett, William R; Mahadevan, Radhakrishnan

    2018-04-15

    Metabolism can exhibit dynamic phenomena like bistability due to the presence of regulatory motifs like the positive feedback loop. As cell factories, microorganisms with bistable metabolism can have a high and a low product flux at the two stable steady states, respectively. The exclusion of metabolic regulation and network dynamics limits the ability of pseudo-steady state stoichiometric models to detect the presence of bistability, and reliably assess the outcomes of design perturbations to metabolic networks. Using kinetic models of metabolism, we assess the change in the bistable characteristics of the network, and suggest designs based on perturbations to the positive feedback loop to enable the network to produce at its theoretical maximum rate. We show that the most optimal production design in parameter space, for a small bistable metabolic network, may exist at the boundary of the bistable region separating it from the monostable region of low product fluxes. The results of our analysis can be broadly applied to other bistable metabolic networks with similar positive feedback network topologies. This can complement existing model-based design strategies by providing a smaller number of feasible designs that need to be tested in vivo. http://lmse.biozone.utoronto.ca/downloads/. krishna.mahadevan@utoronto.ca. Supplementary data are available at Bioinformatics online.

  8. Model-based software engineering for an optical navigation system for spacecraft

    Science.gov (United States)

    Franz, T.; Lüdtke, D.; Maibaum, O.; Gerndt, A.

    2017-09-01

    The project Autonomous Terrain-based Optical Navigation (ATON) at the German Aerospace Center (DLR) is developing an optical navigation system for future landing missions on celestial bodies such as the moon or asteroids. Image data obtained by optical sensors can be used for autonomous determination of the spacecraft's position and attitude. Camera-in-the-loop experiments in the Testbed for Robotic Optical Navigation (TRON) laboratory and flight campaigns with unmanned aerial vehicle (UAV) are performed to gather flight data for further development and to test the system in a closed-loop scenario. The software modules are executed in the C++ Tasking Framework that provides the means to concurrently run the modules in separated tasks, send messages between tasks, and schedule task execution based on events. Since the project is developed in collaboration with several institutes in different domains at DLR, clearly defined and well-documented interfaces are necessary. Preventing misconceptions caused by differences between various development philosophies and standards turned out to be challenging. After the first development cycles with manual Interface Control Documents (ICD) and manual implementation of the complex interactions between modules, we switched to a model-based approach. The ATON model covers a graphical description of the modules, their parameters and communication patterns. Type and consistency checks on this formal level help to reduce errors in the system. The model enables the generation of interfaces and unified data types as well as their documentation. Furthermore, the C++ code for the exchange of data between the modules and the scheduling of the software tasks is created automatically. With this approach, changing the data flow in the system or adding additional components (e.g., a second camera) have become trivial.

  9. Applied, theoretical modeling of space-based assembly, using expert system architecture for computer-aided engineering tool development

    Science.gov (United States)

    Jolly, Steven Douglas

    1992-01-01

    The challenges associated with constructing interplanetary spacecraft and space platforms in low earth orbit are such that it is imperative that comprehensive, preliminary process planning analyses be completed before committing funds for Phase B design (detail design, development). Phase A and 'pre-Phase A' design activities will commonly address engineering questions such as mission-design structural integrity, attitude control, thermal control, etc. But the questions of constructability, maintainability and reliability during the assembly phase usually go unaddressed until the more mature stages of design (or very often production) are reached. This is an unacceptable strategy for future space missions whether they be government or commercial ventures. After interviews with expert Aerospace and Construction industry planners a new methodology was formulated and a Blackboard Metaphor Knowledge-based Expert System synthesis model has been successfully developed which can decompose interplanetary vehicles into deliverable orbital subassemblies. Constraint propagation, including launch vehicle payload shroud envelope, is accomplished with heuristic and numerical algorithms including a unique adaptation of a reasoning technique used by Stanford researchers in terrestrial automated process planning. The model is a hybrid combination of rule and frame-based representations, designed to integrate into a Computer-Aided Engineering (CAE) environment. Emphasis is placed on the actual joining, rendezvous, and refueling of the orbiting, dynamic spacecraft. Significant results of this new methodology upon a large Mars interplanetary spacecraft (736,000 kg) designed by Boeing, show high correlation to manual decomposition and planning analysis studies, but at a fraction of the time, and with little user interaction. Such Computer-Aided Engineering (CAE) tools would greatly leverage the designers ability to assess constructability.

  10. 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.

  11. Model-Based Systems Engineering in the Execution of Search and Rescue Operations

    Science.gov (United States)

    2015-09-01

    SAR DRM Activity Simulation Gantt Chart ...................................................82 Figure 19. SAR DRM Action Utilization Simulation Output...characteristics of the search object. Simulation software , such as the U.S. Coast Guard’s SAROPS, calculates Monte Carlo probability distributions for...construct tends to be somewhat software - centric so the International Council on Systems Engineering decided in 2001 to customize UML for systems

  12. Development and evaluation of a biomedical search engine using a predicate-based vector space model.

    Science.gov (United States)

    Kwak, Myungjae; Leroy, Gondy; Martinez, Jesse D; Harwell, Jeffrey

    2013-10-01

    Although biomedical information available in articles and patents is increasing exponentially, we continue to rely on the same information retrieval methods and use very few keywords to search millions of documents. We are developing a fundamentally different approach for finding much more precise and complete information with a single query using predicates instead of keywords for both query and document representation. Predicates are triples that are more complex datastructures than keywords and contain more structured information. To make optimal use of them, we developed a new predicate-based vector space model and query-document similarity function with adjusted tf-idf and boost function. Using a test bed of 107,367 PubMed abstracts, we evaluated the first essential function: retrieving information. Cancer researchers provided 20 realistic queries, for which the top 15 abstracts were retrieved using a predicate-based (new) and keyword-based (baseline) approach. Each abstract was evaluated, double-blind, by cancer researchers on a 0-5 point scale to calculate precision (0 versus higher) and relevance (0-5 score). Precision was significantly higher (psearching than keywords, laying the foundation for rich and sophisticated information search. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Analysis of the relation between knowledge engineering and knowledge management based on the Nonaka and Takeuchi models

    Directory of Open Access Journals (Sweden)

    Christian Reyes

    2007-07-01

    Full Text Available The use of the Knowledge Management is fundamental in the creation of value within the companies, being at the present time a new form to obtain competitive advantages in specific market. Also, for the process of value creation is necessary to use specifics Information Technologies that they allow to reach the objectives drawn up when implementing a Knowledge Management project. In this sense, one of the more complete and efficient Information Technologies is the Knowledge Based System that as well comprises of the Knowledge Engineering. This article tries to analyze the existing relation between Knowledge Management, a specific model of knowledge creation, the Knowledge Based System and how this Information Technologies play a very important role in the creation, codification and transference of knowledge.

  14. Model Wind Turbine Design in a Project-Based Middle School Engineering Curriculum Built on State Frameworks

    Science.gov (United States)

    Cogger, Steven D.; Miley, Daniel H.

    2012-01-01

    This paper proposes that project-based active learning is a key part of engineering education at the middle school level. One project from a comprehensive middle school engineering curriculum developed by the authors is described to show how active learning and state frameworks can coexist. The theoretical basis for learning and assessment in a…

  15. Modeling the internal combustion engine

    Science.gov (United States)

    Zeleznik, F. J.; Mcbride, B. J.

    1985-01-01

    A flexible and computationally economical model of the internal combustion engine was developed for use on large digital computer systems. It is based on a system of ordinary differential equations for cylinder-averaged properties. The computer program is capable of multicycle calculations, with some parameters varying from cycle to cycle, and has restart capabilities. It can accommodate a broad spectrum of reactants, permits changes in physical properties, and offers a wide selection of alternative modeling functions without any reprogramming. It readily adapts to the amount of information available in a particular case because the model is in fact a hierarchy of five models. The models range from a simple model requiring only thermodynamic properties to a complex model demanding full combustion kinetics, transport properties, and poppet valve flow characteristics. Among its many features the model includes heat transfer, valve timing, supercharging, motoring, finite burning rates, cycle-to-cycle variations in air-fuel ratio, humid air, residual and recirculated exhaust gas, and full combustion kinetics.

  16. Non-linear model-based predictive control of a low-temperature gasoline combustion engine

    OpenAIRE

    Hoffmann, Kai

    2010-01-01

    Topic of this thesis is the development of a non-linear MPC for the lowtemperature gasoline combustion (CAI) in a four-stroke single-cylinder engine. This process must be steered without the actuator of the spark plug. Moreover, smallest changes in the ambient conditions move the self-ignition towards disadvantageous timings and a rough combustion. For actuating the combustion in the single-cylinder demonstrator, the valve timings of the electro-mechanical valve train and the direct injection...

  17. MODELS OF PROJECT REVERSE ENGINEERING

    OpenAIRE

    Віктор Володимирович ІВАНОВ

    2017-01-01

    Reverse engineering decided important scientific and technical problems of increasing the cost of the existing technical product by transforming it into a product with other features or design. Search ideas of the new application of existing products on the base of heuristic analysis were created. The concept of reverse engineering and its division into three types: conceptual, aggregate and complete was expanded. The use of heuristic methods for reverse engineering concept was showed. The mo...

  18. Computational Modeling in Tissue Engineering

    CERN Document Server

    2013-01-01

    One of the major challenges in tissue engineering is the translation of biological knowledge on complex cell and tissue behavior into a predictive and robust engineering process. Mastering this complexity is an essential step towards clinical applications of tissue engineering. This volume discusses computational modeling tools that allow studying the biological complexity in a more quantitative way. More specifically, computational tools can help in:  (i) quantifying and optimizing the tissue engineering product, e.g. by adapting scaffold design to optimize micro-environmental signals or by adapting selection criteria to improve homogeneity of the selected cell population; (ii) quantifying and optimizing the tissue engineering process, e.g. by adapting bioreactor design to improve quality and quantity of the final product; and (iii) assessing the influence of the in vivo environment on the behavior of the tissue engineering product, e.g. by investigating vascular ingrowth. The book presents examples of each...

  19. Assessment on Time-Varying Thermal Loading of Engineering Structures Based on a New Solar Radiation Model

    Directory of Open Access Journals (Sweden)

    Bo Chen

    2014-01-01

    Full Text Available This paper aims to carry out the condition assessment on solar radiation model and thermal loading of bridges. A modification factor is developed to change the distribution of solar intensities during a whole day. In addition, a new solar radiation model for civil engineering structures is proposed to consider the shelter effects induced by cloud, mountains, and surrounding structures. The heat transfer analysis of bridge components is conducted to calculate the temperature distributions based on the proposed new solar radiation model. By assuming that the temperature along the bridge longitudinal direction is constant, one typical bridge segment is specially studied. Fine finite element models of deck plates and corrugate sheets are constructed to examine the temperature distributions and thermal loading of bridge components. The feasibility and validity of the proposed solar radiation model are investigated through detailed numerical simulation and parametric study. The numerical results are compared with the field measurement data obtained from the long-term monitoring system of the bridge and they shows a very good agreement in terms of temperature distribution in different time instants and in different seasons. The real application verifies effectiveness and validity of the proposed solar radiation and heat transfer analysis.

  20. Modeling Diesel Engine Injector Flows

    National Research Council Canada - National Science Library

    Heister, S

    2001-01-01

    Models have been developed to assess flow fields inside diesel injector orifice passages in order to increase our understanding of the spray formation process which governs performance and emissions in these engines...

  1. Model based systems engineering (MBSE) applied to Radio Aurora Explorer (RAX) CubeSat mission operational scenarios

    Science.gov (United States)

    Spangelo, S. C.; Cutler, J.; Anderson, L.; Fosse, E.; Cheng, L.; Yntema, R.; Bajaj, M.; Delp, C.; Cole, B.; Soremekum, G.; Kaslow, D.

    Small satellites are more highly resource-constrained by mass, power, volume, delivery timelines, and financial cost relative to their larger counterparts. Small satellites are operationally challenging because subsystem functions are coupled and constrained by the limited available commodities (e.g. data, energy, and access times to ground resources). Furthermore, additional operational complexities arise because small satellite components are physically integrated, which may yield thermal or radio frequency interference. In this paper, we extend our initial Model Based Systems Engineering (MBSE) framework developed for a small satellite mission by demonstrating the ability to model different behaviors and scenarios. We integrate several simulation tools to execute SysML-based behavior models, including subsystem functions and internal states of the spacecraft. We demonstrate utility of this approach to drive the system analysis and design process. We demonstrate applicability of the simulation environment to capture realistic satellite operational scenarios, which include energy collection, the data acquisition, and downloading to ground stations. The integrated modeling environment enables users to extract feasibility, performance, and robustness metrics. This enables visualization of both the physical states (e.g. position, attitude) and functional states (e.g. operating points of various subsystems) of the satellite for representative mission scenarios. The modeling approach presented in this paper offers satellite designers and operators the opportunity to assess the feasibility of vehicle and network parameters, as well as the feasibility of operational schedules. This will enable future missions to benefit from using these models throughout the full design, test, and fly cycle. In particular, vehicle and network parameters and schedules can be verified prior to being implemented, during mission operations, and can also be updated in near real-time with oper

  2. Proposal of thinking process model based on putting a question to oneself for problem solving by skilled engineers

    International Nuclear Information System (INIS)

    Fukumoto, Toshihiko; Kishi, Yoshiki

    2007-01-01

    The retirement of the skilled engineers and researchers, who have been working in the field of water chemistry of BWRs since the establishment of Japanese BWRs, has been accelerating so that it is necessary to preserve and share the knowledge and know-how of these skilled engineers and to effectively and securely inherit them to the following generations. Moreover, in order for other engineers to share knowledge, including the tacit knowledge of a skilled engineer, it is necessary not only to understand the knowledge obtained as the results of the thinking of the skilled engineers but also to externalize and experience their thinking processes as the processes of problem solving that produced the results. The target of this research is to build a new thinking process model that can externalize thinking processes effectively by analyzing the knowledge and thinking contents of the skilled engineers for investigating causes of changes in the quality of reactor water in boiling water reactor type power plants. As part of this research, we found out a new metacognitive activity, Putting a Question to Oneself, which plays a large role in the thinking process structure. In addition, we developed a new fundamental thinking process model, which can externalize thinking processes effectively by integrating the concept of Putting a Question to Oneself into the thinking process model. (author)

  3. Model-Based Systems Engineering With the Architecture Analysis and Design Language (AADL) Applied to NASA Mission Operations

    Science.gov (United States)

    Munoz Fernandez, Michela Miche

    2014-01-01

    The potential of Model Model Systems Engineering (MBSE) using the Architecture Analysis and Design Language (AADL) applied to space systems will be described. AADL modeling is applicable to real-time embedded systems- the types of systems NASA builds. A case study with the Juno mission to Jupiter showcases how this work would enable future missions to benefit from using these models throughout their life cycle from design to flight operations.

  4. An engineered 3D human airway mucosa model based on an SIS scaffold.

    Science.gov (United States)

    Steinke, Maria; Gross, Roy; Walles, Heike; Gangnus, Rainer; Schütze, Karin; Walles, Thorsten

    2014-08-01

    To investigate interrelations of human obligate airway pathogens, such as Bordetella pertussis, and their hosts test systems with high in vitro/in vivo correlation are of urgent need. Using a tissue engineering approach, we generated a 3D test system of the airway mucosa with human tracheobronchial epithelial cells (hTEC) and fibroblasts seeded on a clinically implemented biological scaffold. To investigate if hTEC display tumour-specific characteristics we analysed Raman spectra of hTEC and the adenocarcinoma cell line Calu-3. To establish optimal conditions for infection studies, we treated human native airway mucosa segments with B. pertussis. Samples were processed for morphologic analysis. Whereas our test system consisting of differentiated epithelial cells and migrating fibroblasts shows high in vitro/in vivo correlation, hTEC seeded on the scaffold as monocultures did not resemble the in vivo situation. Differences in Raman spectra of hTEC and Calu-3 were identified in distinct wave number ranges between 720 and 1662 cm(-1) indicating that hTEC do not display tumour-specific characteristics. Infection of native tissue with B. pertussis led to cytoplasmic vacuoles, damaged mitochondria and destroyed epithelial cells. Our test system is suitable for infection studies with human obligate airway pathogens by mimicking the physiological microenvironment of the human airway mucosa. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Modelling and Simulation of Search Engine

    Science.gov (United States)

    Nasution, Mahyuddin K. M.

    2017-01-01

    The best tool currently used to access information is a search engine. Meanwhile, the information space has its own behaviour. Systematically, an information space needs to be familiarized with mathematics so easily we identify the characteristics associated with it. This paper reveal some characteristics of search engine based on a model of document collection, which are then estimated the impact on the feasibility of information. We reveal some of characteristics of search engine on the lemma and theorem about singleton and doubleton, then computes statistically characteristic as simulating the possibility of using search engine. In this case, Google and Yahoo. There are differences in the behaviour of both search engines, although in theory based on the concept of documents collection.

  6. TriBITS lifecycle model. Version 1.0, a lean/agile software lifecycle model for research-based computational science and engineering and applied mathematical software.

    Energy Technology Data Exchange (ETDEWEB)

    Willenbring, James M.; Bartlett, Roscoe Ainsworth (Oak Ridge National Laboratory, Oak Ridge, TN); Heroux, Michael Allen

    2012-01-01

    Software lifecycles are becoming an increasingly important issue for computational science and engineering (CSE) software. The process by which a piece of CSE software begins life as a set of research requirements and then matures into a trusted high-quality capability is both commonplace and extremely challenging. Although an implicit lifecycle is obviously being used in any effort, the challenges of this process - respecting the competing needs of research vs. production - cannot be overstated. Here we describe a proposal for a well-defined software lifecycle process based on modern Lean/Agile software engineering principles. What we propose is appropriate for many CSE software projects that are initially heavily focused on research but also are expected to eventually produce usable high-quality capabilities. The model is related to TriBITS, a build, integration and testing system, which serves as a strong foundation for this lifecycle model, and aspects of this lifecycle model are ingrained in the TriBITS system. Here, we advocate three to four phases or maturity levels that address the appropriate handling of many issues associated with the transition from research to production software. The goals of this lifecycle model are to better communicate maturity levels with customers and to help to identify and promote Software Engineering (SE) practices that will help to improve productivity and produce better software. An important collection of software in this domain is Trilinos, which is used as the motivation and the initial target for this lifecycle model. However, many other related and similar CSE (and non-CSE) software projects can also make good use of this lifecycle model, especially those that use the TriBITS system. Indeed this lifecycle process, if followed, will enable large-scale sustainable integration of many complex CSE software efforts across several institutions.

  7. Modeling of Combined Heat and Power Plant Based on a Multi-Stage Gasifier and Internal Combustion Engines of Various Power Outputs

    Science.gov (United States)

    Khudyakova, G. I.; Kozlov, A. N.; Svishchev, D. A.

    2017-11-01

    The paper is concerned with an integrated system of internal combustion engine and mini combined heat and power plant (ICE-CHP). The system is based on multi-stage wood biomass gasification. The use of producer gas in the system affects negatively the internal combustion engine performance and, therefore, reduces the efficiency of the ICE-CHP plant. A mathematical model of an internal combustion engine running on low-calorie producer gas was developed using an overview of Russian and foreign manufacturers of reciprocating units, that was made in the research. A thermal calculation was done for four-stroke gas engines of different rated power outputs (30, 100 and 250 kW), running on producer gas (CO2 - 10.2, CO - 45.8, N2 - 38.8%). Thermal calculation demonstrates that the engine exhaust gas temperature reaches 500 - 600°C at the rated power level and with the lower engine power, the temperature gets higher. For example, for an internal combustion engine power of 1000 kW the temperature of exhaust gases equals 400°C. A comparison of the efficiency of engine operation on natural gas and producer gas shows that with the use of producer gas the power output declines from 300 to 250 kWe. The reduction in the effective efficiency in this case makes up 2%. The measures are proposed to upgrade the internal combustion engine to enable it to run on low-calorie producer gas.

  8. A Novel Machine Learning Strategy Based on Two-Dimensional Numerical Models in Financial Engineering

    Directory of Open Access Journals (Sweden)

    Qingzhen Xu

    2013-01-01

    Full Text Available Machine learning is the most commonly used technique to address larger and more complex tasks by analyzing the most relevant information already present in databases. In order to better predict the future trend of the index, this paper proposes a two-dimensional numerical model for machine learning to simulate major U.S. stock market index and uses a nonlinear implicit finite-difference method to find numerical solutions of the two-dimensional simulation model. The proposed machine learning method uses partial differential equations to predict the stock market and can be extensively used to accelerate large-scale data processing on the history database. The experimental results show that the proposed algorithm reduces the prediction error and improves forecasting precision.

  9. Development of Demonstrably Predictive Models for Emissions from Alternative Fuels Based Aircraft Engines

    Science.gov (United States)

    2017-05-01

    requires detailed models from the small scales (chemical reactions, soot evolution) to the largest scales (energy containing turbulence features). The...was a mixture of 75% n- dodecane and 25% m-xylene by volume. Table 2 and 3 contain relevant information for all fuels considered in this investigation...beam, and h the height above the burner. By measuring the integral extinction and utilizing the Lambert- Beer formula IhLaser = I0Laser;hexpZ0 L

  10. Volterra-series-based nonlinear system modeling and its engineering applications: A state-of-the-art review

    Science.gov (United States)

    Cheng, C. M.; Peng, Z. K.; Zhang, W. M.; Meng, G.

    2017-03-01

    Nonlinear problems have drawn great interest and extensive attention from engineers, physicists and mathematicians and many other scientists because most real systems are inherently nonlinear in nature. To model and analyze nonlinear systems, many mathematical theories and methods have been developed, including Volterra series. In this paper, the basic definition of the Volterra series is recapitulated, together with some frequency domain concepts which are derived from the Volterra series, including the general frequency response function (GFRF), the nonlinear output frequency response function (NOFRF), output frequency response function (OFRF) and associated frequency response function (AFRF). The relationship between the Volterra series and other nonlinear system models and nonlinear problem solving methods are discussed, including the Taylor series, Wiener series, NARMAX model, Hammerstein model, Wiener model, Wiener-Hammerstein model, harmonic balance method, perturbation method and Adomian decomposition. The challenging problems and their state of arts in the series convergence study and the kernel identification study are comprehensively introduced. In addition, a detailed review is then given on the applications of Volterra series in mechanical engineering, aeroelasticity problem, control engineering, electronic and electrical engineering.

  11. Engine modeling and control modeling and electronic management of internal combustion engines

    CERN Document Server

    Isermann, Rolf

    2014-01-01

    The increasing demands for internal combustion engines with regard to fuel consumption, emissions and driveability lead to more actuators, sensors and complex control functions. A systematic implementation of the electronic control systems requires mathematical models from basic design through simulation to calibration. The book treats physically-based as well as models based experimentally on test benches for gasoline (spark ignition) and diesel (compression ignition) engines and uses them for the design of the different control functions. The main topics are: - Development steps for engine control - Stationary and dynamic experimental modeling - Physical models of intake, combustion, mechanical system, turbocharger, exhaust, cooling, lubrication, drive train - Engine control structures, hardware, software, actuators, sensors, fuel supply, injection system, camshaft - Engine control methods, static and dynamic feedforward and feedback control, calibration and optimization, HiL, RCP, control software developm...

  12. Conceptual Models for Search Engines

    Science.gov (United States)

    Hendry, D. G.; Efthimiadis, E. N.

    Search engines have entered popular culture. They touch people in diverse private and public settings and thus heighten the importance of such important social matters as information privacy and control, censorship, and equitable access. To fully benefit from search engines and to participate in debate about their merits, people necessarily appeal to their understandings for how they function. In this chapter we examine the conceptual understandings that people have of search engines by performing a content analysis on the sketches that 200 undergraduate and graduate students drew when asked to draw a sketch of how a search engine works. Analysis of the sketches reveals a diverse range of conceptual approaches, metaphors, representations, and misconceptions. On the whole, the conceptual models articulated by these students are simplistic. However, students with higher levels of academic achievement sketched more complete models. This research calls attention to the importance of improving students' technical knowledge of how search engines work so they can be better equipped to develop and advocate policies for how search engines should be embedded in, and restricted from, various private and public information settings.

  13. Atmospheric Models for Engineering Applications

    Science.gov (United States)

    Johnson, Dale L.; Roberts, Barry C.; Vaughan, William W.; Justus, C. G.

    2002-01-01

    This paper will review the historical development of reference and standard atmosphere models and their applications. The evolution of the U.S. Standard Atmosphere will be addressed, along with the Range Reference Atmospheres and, in particular, the NASA Global Reference Atmospheric Model (GRAM). The extensive scope and content of the GRAM will be addressed since it represents the most extensive and complete 'Reference' atmosphere model in use today. Its origin was for engineering applications and that remains today as its principal use.

  14. A mathematical framework for yield (vs. rate) optimization in constraint-based modeling and applications in metabolic engineering.

    Science.gov (United States)

    Klamt, Steffen; Müller, Stefan; Regensburger, Georg; Zanghellini, Jürgen

    2018-02-07

    The optimization of metabolic rates (as linear objective functions) represents the methodical core of flux-balance analysis techniques which have become a standard tool for the study of genome-scale metabolic models. Besides (growth and synthesis) rates, metabolic yields are key parameters for the characterization of biochemical transformation processes, especially in the context of biotechnological applications. However, yields are ratios of rates, and hence the optimization of yields (as nonlinear objective functions) under arbitrary linear constraints is not possible with current flux-balance analysis techniques. Despite the fundamental importance of yields in constraint-based modeling, a comprehensive mathematical framework for yield optimization is still missing. We present a mathematical theory that allows one to systematically compute and analyze yield-optimal solutions of metabolic models under arbitrary linear constraints. In particular, we formulate yield optimization as a linear-fractional program. For practical computations, we transform the linear-fractional yield optimization problem to a (higher-dimensional) linear problem. Its solutions determine the solutions of the original problem and can be used to predict yield-optimal flux distributions in genome-scale metabolic models. For the theoretical analysis, we consider the linear-fractional problem directly. Most importantly, we show that the yield-optimal solution set (like the rate-optimal solution set) is determined by (yield-optimal) elementary flux vectors of the underlying metabolic model. However, yield- and rate-optimal solutions may differ from each other, and hence optimal (biomass or product) yields are not necessarily obtained at solutions with optimal (growth or synthesis) rates. Moreover, we discuss phase planes/production envelopes and yield spaces, in particular, we prove that yield spaces are convex and provide algorithms for their computation. We illustrate our findings by a small

  15. Estimating decades-long trends in petroleum field energy return on investment (EROI) with an engineering-based model.

    Science.gov (United States)

    Tripathi, Vinay S; Brandt, Adam R

    2017-01-01

    This paper estimates changes in the energy return on investment (EROI) for five large petroleum fields over time using the Oil Production Greenhouse Gas Emissions Estimator (OPGEE). The modeled fields include Cantarell (Mexico), Forties (U.K.), Midway-Sunset (U.S.), Prudhoe Bay (U.S.), and Wilmington (U.S.). Data on field properties and production/processing parameters were obtained from a combination of government and technical literature sources. Key areas of uncertainty include details of the oil and gas surface processing schemes. We aim to explore how long-term trends in depletion at major petroleum fields change the effective energetic productivity of petroleum extraction. Four EROI ratios are estimated for each field as follows: The net energy ratio (NER) and external energy ratio (EER) are calculated, each using two measures of energy outputs, (1) oil-only and (2) all energy outputs. In all cases, engineering estimates of inputs are used rather than expenditure-based estimates (including off-site indirect energy use and embodied energy). All fields display significant declines in NER over the modeling period driven by a combination of (1) reduced petroleum production and (2) increased energy expenditures on recovery methods such as the injection of water, steam, or gas. The fields studied had NER reductions ranging from 46% to 88% over the modeling periods (accounting for all energy outputs). The reasons for declines in EROI differ by field. Midway-Sunset experienced a 5-fold increase in steam injected per barrel of oil produced. In contrast, Prudhoe Bay has experienced nearly a 30-fold increase in amount of gas processed and reinjected per unit of oil produced. In contrast, EER estimates are subject to greater variability and uncertainty due to the relatively small magnitude of external energy investments in most cases.

  16. Model-based system engineering to evaluate I and C systems human performance in nuclear power plants - 15207

    International Nuclear Information System (INIS)

    Alves, P.; Mesquita, F.; Kessel, D.; Jung, J.

    2015-01-01

    In a Nuclear Power Plant, many advantages can be obtained by introducing digital instrumentation and control (I and C) systems, such as safety improvement in fault tolerance, self-testing, signal validation, better calibration and greater data capacity. The digital system must be able to meet the needs of the plants and also be compatible with operator capabilities, in a matter that will reduce human error probability. The safety systems must be reliable, with high functionality and availability, and it is essential to have redundancy, independence and diversity among components. I and C systems require a full understanding from plant operators. This paper is intent to propose, by using the C4ISR framework, a simpler and more comprehensive way to represent the architecture of the I and C system framework. The C4ISR framework gives the possibility to define the system under 3 different views: Operational View, Systems View, and Technical View; By using the CORE model-based system engineering software, the systems view of the Plant Protection System is analyzed

  17. The Development and Evaluation of a Time Based Network Model of the Industrial Engineering Technology Curriculum at the Southern Technical Institute.

    Science.gov (United States)

    Bannerman, James W.

    A practicum was conducted to develop a scientific management tool that would assist students in obtaining a systems view of their college curriculum and to coordinate planning with curriculum requirements. A modification of the critical path method was employed and the result was a time-based network model of the Industrial Engineering Technology…

  18. Technique for obtaining an engine emissions model based on continuous EPA-CVS test data and a dynamic vehicle model. SAE Paper 760156

    Energy Technology Data Exchange (ETDEWEB)

    Radtke, R.; Frank, A.; Beachley, N.

    1976-01-01

    A new technique for obtaining engine emission flow rate maps has been developed. The maps are based on specific emissions data obtained on a continuous basis over a single EPA-CVS urban driving cycle test. The data are averaged for the various torque-speed ranges of the engine. It has been found that these dynamic average emission flow rate maps, which are functions only of engine torque and speed, allow instantaneous emissions to be fairly accurately predicted. It also appears that the technique might be used advantageously to determine engine calibration parameters.

  19. Cycle Engine Modelling Of Spark Ignition Engine Processes during Wide-Open Throttle (WOT) Engine Operation Running By Gasoline Fuel

    International Nuclear Information System (INIS)

    Rahim, M F Abdul; Rahman, M M; Bakar, R A

    2012-01-01

    One-dimensional engine model is developed to simulate spark ignition engine processes in a 4-stroke, 4 cylinders gasoline engine. Physically, the baseline engine is inline cylinder engine with 3-valves per cylinder. Currently, the engine's mixture is formed by external mixture formation using piston-type carburettor. The model of the engine is based on one-dimensional equation of the gas exchange process, isentropic compression and expansion, progressive engine combustion process, and accounting for the heat transfer and frictional losses as well as the effect of valves overlapping. The model is tested for 2000, 3000 and 4000 rpm of engine speed and validated using experimental engine data. Results showed that the engine is able to simulate engine's combustion process and produce reasonable prediction. However, by comparing with experimental data, major discrepancy is noticeable especially on the 2000 and 4000 rpm prediction. At low and high engine speed, simulated cylinder pressures tend to under predict the measured data. Whereas the cylinder temperatures always tend to over predict the measured data at all engine speed. The most accurate prediction is obtained at medium engine speed of 3000 rpm. Appropriate wall heat transfer setup is vital for more precise calculation of cylinder pressure and temperature. More heat loss to the wall can lower cylinder temperature. On the hand, more heat converted to the useful work mean an increase in cylinder pressure. Thus, instead of wall heat transfer setup, the Wiebe combustion parameters are needed to be carefully evaluated for better results.

  20. Genetically engineered mesenchymal stromal cells produce IL-3 and TPO to further improve human scaffold-based xenograft models.

    Science.gov (United States)

    Carretta, Marco; de Boer, Bauke; Jaques, Jenny; Antonelli, Antonella; Horton, Sarah J; Yuan, Huipin; de Bruijn, Joost D; Groen, Richard W J; Vellenga, Edo; Schuringa, Jan Jacob

    2017-07-01

    Recently, NOD-SCID IL2Rγ -/- (NSG) mice were implanted with human mesenchymal stromal cells (MSCs) in the presence of ceramic scaffolds or Matrigel to mimic the human bone marrow (BM) microenvironment. This approach allowed the engraftment of leukemic samples that failed to engraft in NSG mice without humanized niches and resulted in a better preservation of leukemic stem cell self-renewal properties. To further improve our humanized niche scaffold model, we genetically engineered human MSCs to secrete human interleukin-3 (IL-3) and thrombopoietin (TPO). In vitro, these IL-3- and TPO-producing MSCs were superior in expanding human cord blood (CB) CD34 + hematopoietic stem/progenitor cells. MLL-AF9-transduced CB CD34 + cells could be transformed efficiently along myeloid or lymphoid lineages on IL-3- and TPO-producing MSCs. In vivo, these genetically engineered MSCs maintained their ability to differentiate into bone, adipocytes, and other stromal components. Upon transplantation of MLL-AF9-transduced CB CD34 + cells, acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) developed in engineered scaffolds, in which a significantly higher percentage of myeloid clones was observed in the mouse compartments compared with previous models. Engraftment of primary AML, B-cell ALL, and biphenotypic acute leukemia (BAL) patient samples was also evaluated, and all patient samples could engraft efficiently; the myeloid compartment of the BAL samples was better preserved in the human cytokine scaffold model. In conclusion, we show that we can genetically engineer the ectopic human BM microenvironment in a humanized scaffold xenograft model. This approach will be useful for functional study of the importance of niche factors in normal and malignant human hematopoiesis. Copyright © 2017 ISEH - International Society for Experimental Hematology. All rights reserved.

  1. Impact of two-stage turbocharging architectures on pumping losses of automotive engines based on an analytical model

    International Nuclear Information System (INIS)

    Galindo, J.; Serrano, J.R.; Climent, H.; Varnier, O.

    2010-01-01

    Present work presents an analytical study of two-stage turbocharging configuration performance. The aim of this work is to understand the influence of different two-stage-architecture parameters to optimize the use of exhaust manifold gases energy and to aid decision making process. An analytical model giving the relationship between global compression ratio and global expansion ratio is developed as a function of basic engine and turbocharging system parameters. Having an analytical solution, the influence of different variables, such as expansion ratio between HP and LP turbine, intercooler efficiency, turbochargers efficiency, cooling fluid temperature and exhaust temperature are studied independently. Engine simulations with proposed analytical model have been performed to analyze the influence of these different parameters on brake thermal efficiency and pumping mean effective pressure. The results obtained show the overall performance of the two-stage system for the whole operative range and characterize the optimum control of the elements for each operative condition. The model was also used to compare single-stage and two-stage architectures performance for the same engine operative conditions. Benefits and limits in terms of breathing capabilities and brake thermal efficiency of each type of system have been presented and analyzed.

  2. A New Predictive Model Based on the ABC Optimized Multivariate Adaptive Regression Splines Approach for Predicting the Remaining Useful Life in Aircraft Engines

    Directory of Open Access Journals (Sweden)

    Paulino José García Nieto

    2016-05-01

    Full Text Available Remaining useful life (RUL estimation is considered as one of the most central points in the prognostics and health management (PHM. The present paper describes a nonlinear hybrid ABC–MARS-based model for the prediction of the remaining useful life of aircraft engines. Indeed, it is well-known that an accurate RUL estimation allows failure prevention in a more controllable way so that the effective maintenance can be carried out in appropriate time to correct impending faults. The proposed hybrid model combines multivariate adaptive regression splines (MARS, which have been successfully adopted for regression problems, with the artificial bee colony (ABC technique. This optimization technique involves parameter setting in the MARS training procedure, which significantly influences the regression accuracy. However, its use in reliability applications has not yet been widely explored. Bearing this in mind, remaining useful life values have been predicted here by using the hybrid ABC–MARS-based model from the remaining measured parameters (input variables for aircraft engines with success. A correlation coefficient equal to 0.92 was obtained when this hybrid ABC–MARS-based model was applied to experimental data. The agreement of this model with experimental data confirmed its good performance. The main advantage of this predictive model is that it does not require information about the previous operation states of the aircraft engine.

  3. Tag Based Audio Search Engine

    OpenAIRE

    Parameswaran Vellachu; Sunitha Abburu

    2012-01-01

    The volume of the music database is increasing day by day. Getting the required song as per the choice of the listener is a big challenge. Hence, it is really hard to manage this huge quantity, in terms of searching, filtering, through the music database. It is surprising to see that the audio and music industry still rely on very simplistic metadata to describe music files. However, while searching audio resource, an efficient "Tag Based Audio Search Engine" is necessary. The current researc...

  4. A Model-Based Product Evaluation Protocol for Comparison of Safety-Engineered Protection Mechanisms of Winged Blood Collection Needles.

    Science.gov (United States)

    Haupt, C; Spaeth, J; Ahne, T; Goebel, U; Steinmann, D

    2016-05-01

    To evaluate differences in product characteristics and user preferences of safety-engineered protection mechanisms of winged blood collection needles. Randomized model-based simulation study. University medical center. A total of 33 third-year medical students. Venipuncture was performed using winged blood collection needles with 4 different safety mechanisms: (a) Venofix Safety, (b) BD Vacutainer Push Button, (c) Safety-Multifly, and (d) Surshield Surflo. Each needle type was used in 3 consecutive tries: there was an uninstructed first handling, then instructions were given according to the operating manual; subsequently, a first trial and second trial were conducted. Study end points included successful activation, activation time, single-handed activation, correct activation, possible risk of needlestick injury, possibility of deactivation, and preferred safety mechanism. The overall successful activation rate during the second trial was equal for all 4 devices (94%-100%). Median activation time was (a) 7 s, (b) 2 s, (c) 9 s, and (d) 7 s. Single-handed activation during the second trial was (a) 18%, (b) 82%, (c) 15%, and (d) 45%. Correct activation during the second trial was (a) 3%, (b) 64%, (c) 15%, and (d) 39%. Possible risk of needlestick injury during the second trial was highest with (d). Possibility of deactivation was (a) 0%, (b) 12%, (c) 9%, and (d) 18%. Individual preferences for each system were (a) 11, (b) 17, (c) 5, and (d) 0. The main reason for preference was the comprehensive safety mechanism. Significant differences exist between safety mechanisms of winged blood collection needles.

  5. Engineered Swine Models of Cancer

    Directory of Open Access Journals (Sweden)

    Adrienne L. Watson

    2016-05-01

    Full Text Available Over the past decade, the technology to engineer genetically modified swine has seen many advancements, and because their physiology is remarkably similar to that of humans, swine models of cancer may be extremely valuable for preclinical safety studies as well as toxicity testing of pharmaceuticals prior to the start of human clinical trials. Hence, the benefits of using swine as a large animal model in cancer research and the potential applications and future opportunities of utilizing pigs in cancer modeling are immense. In this review, we discuss how pigs have been and can be used as a biomedical models for cancer research, with an emphasis on current technologies. We have focused on applications of precision genetics that can provide models that mimic human cancer predisposition syndromes. In particular, we describe the advantages of targeted gene-editing using custom endonucleases, specifically TALENs and CRISPRs, and transposon systems, to make novel pig models of cancer with broad preclinical applications.

  6. Service Modeling for Service Engineering

    Science.gov (United States)

    Shimomura, Yoshiki; Tomiyama, Tetsuo

    Intensification of service and knowledge contents within product life cycles is considered crucial for dematerialization, in particular, to design optimal product-service systems from the viewpoint of environmentally conscious design and manufacturing in advanced post industrial societies. In addition to the environmental limitations, we are facing social limitations which include limitations of markets to accept increasing numbers of mass-produced artifacts and such environmental and social limitations are restraining economic growth. To attack and remove these problems, we need to reconsider the current mass production paradigm and to make products have more added values largely from knowledge and service contents to compensate volume reduction under the concept of dematerialization. Namely, dematerialization of products needs to enrich service contents. However, service was mainly discussed within marketing and has been mostly neglected within traditional engineering. Therefore, we need new engineering methods to look at services, rather than just functions, called "Service Engineering." To establish service engineering, this paper proposes a modeling technique of service.

  7. Developing photoreceptor-based models of visual attraction in riverine tsetse, for use in the engineering of more-attractive polyester fabrics for control devices.

    Directory of Open Access Journals (Sweden)

    Roger D Santer

    2017-03-01

    Full Text Available Riverine tsetse transmit the parasites that cause the most prevalent form of human African trypanosomiasis, Gambian HAT. In response to the imperative for cheap and efficient tsetse control, insecticide-treated 'tiny targets' have been developed through refinement of tsetse attractants based on blue fabric panels. However, modern blue polyesters used for this purpose attract many less tsetse than traditional phthalogen blue cottons. Therefore, colour engineering polyesters for improved attractiveness has great potential for tiny target development. Because flies have markedly different photoreceptor spectral sensitivities from humans, and the responses of these photoreceptors provide the inputs to their visually guided behaviours, it is essential that polyester colour engineering be guided by fly photoreceptor-based explanations of tsetse attraction. To this end, tsetse attraction to differently coloured fabrics was recently modelled using the calculated excitations elicited in a generic set of fly photoreceptors as predictors. However, electrophysiological data from tsetse indicate the potential for modified spectral sensitivities versus the generic pattern, and processing of fly photoreceptor responses within segregated achromatic and chromatic channels has long been hypothesised. Thus, I constructed photoreceptor-based models explaining the attraction of G. f. fuscipes to differently coloured tiny targets recorded in a previously published investigation, under differing assumptions about tsetse spectral sensitivities and organisation of visual processing. Models separating photoreceptor responses into achromatic and chromatic channels explained attraction better than earlier models combining weighted photoreceptor responses in a single mechanism, regardless of the spectral sensitivities assumed. However, common principles for fabric colour engineering were evident across the complete set of models examined, and were consistent with earlier

  8. Model engineering in a modular PSA

    International Nuclear Information System (INIS)

    Friedlhuber, Thomas

    2014-01-01

    For the purpose of PSA (Probabilistic Safety Analysis) for complex industrial systems, often PSA models in the form of fault and event trees are developed to model the risk of unwanted situations (hazards). While the recent decades, PSA models have gained high acceptance and have been developed massively. This lead to an increase in model sizes and complexity. Today, PSA models are often difficult to understand and maintain. This manuscript presents the concept of a modular PSA. A modular PSA tries to cope with the increased complexity by the techniques of modularization and instantiation. Modularization targets to treat a model by smaller pieces (the 'modules') to regain control over models. Instantiation aims to configure a generic model to different contexts. Both try to reduce model complexity. A modular PSA proposes new functionality to manage PSA models. Current model management is rather limited and not efficient. This manuscript shows new methods to manage the evolutions (versions) and deviations (variants) of PSA models in a modular PSA. The concepts of version and variant management are presented in this thesis. In this context, a model comparison and fusion of PSA models is precised. Model comparison provides important feedback to model engineers and model fusion kind of combines the work from different model engineers (concurrent model engineering). Apart from model management, methods to understand the content of PSA models are presented. The methods focus to highlight the dependencies between modules rather than their contents. Dependencies are automatically derived from a model structure. They express relations between model objects (for example a fault tree may have dependencies to basic events). To visualize those dependencies (for example in form of a model cartography) can constitute a crucial aid to model engineers for understanding complex interrelations in PSA models. Within the scope of this thesis, a software named 'Andromeda' has been

  9. Noise exposure levels from model airplane engines.

    Science.gov (United States)

    Pearlman, R C; Miller, M

    1985-01-01

    Previous research indicates that noise levels from unmuffled model airplane engines produce sufficient noise to cause TTS. The present study explored SPLs of smaller engines under 3.25 cc (.19 cu. in.) and the effectiveness of engine mufflers. Results showed that model airplanes can exceed a widely used damage risk criterion (DRC) but that engine mufflers can reduce levels below DRC. Handling model gasoline engines should be added to the list of recreational activities such as snow-mobile and motorcycle riding, shooting, etc. in which the participant's hearing may be in jeopardy. Suggestions are presented to the model engine enthusiast for avoiding damage to hearing.

  10. Engineering graphic modelling a workbook for design engineers

    CERN Document Server

    Tjalve, E; Frackmann Schmidt, F

    2013-01-01

    Engineering Graphic Modelling: A Practical Guide to Drawing and Design covers how engineering drawing relates to the design activity. The book describes modeled properties, such as the function, structure, form, material, dimension, and surface, as well as the coordinates, symbols, and types of projection of the drawing code. The text provides drawing techniques, such as freehand sketching, bold freehand drawing, drawing with a straightedge, a draughting machine or a plotter, and use of templates, and then describes the types of drawing. Graphic designers, design engineers, mechanical engine

  11. Integrating Surface Modeling into the Engineering Design Graphics Curriculum

    Science.gov (United States)

    Hartman, Nathan W.

    2006-01-01

    It has been suggested there is a knowledge base that surrounds the use of 3D modeling within the engineering design process and correspondingly within engineering design graphics education. While solid modeling receives a great deal of attention and discussion relative to curriculum efforts, and rightly so, surface modeling is an equally viable 3D…

  12. Markov Logic Based Inference Engine for CDSS

    International Nuclear Information System (INIS)

    Bajwa, I.S.; Ramzan, B.; Ramzan, S.

    2017-01-01

    CDSS (Clinical Decision Support System) is typically a diagnostic application and a modern technology that can be employed to provide standardized and quality medical facilities to the medical patients especially when expert doctors are not available at the medical centres. These days the use of the CDSSs is quite common in medical practice at remote areas. A CDSS can be very helpful not only in preventive health care but also in computerized diagnosis. However, a typical problem of CDSS based diagnosis is uncertainty. Typically, an ambiguity can occur when a patient is not able to explain the symptoms of his disease in a better way. The typically used forward chaining mechanisms in rule based decision support systems perform reasoning with uncertain data. ML (Markov Logic) is a new technique that has ability to deal with uncertainty of data by integrating FOL (First-Order-Logic) with probabilistic graphical models. In this paper, we have proposed the architecture of a ML based inference engine for a rule based CDSS and we have also presented an algorithm to use ML based forward chaining mechanism in the proposed inference engine. The results of the experiments show that the proposed inference engine would be intelligent enough to diagnose a patient's disease even from uncertain or incomplete/partial information. (author)

  13. Energy Return on Investment (EROI) for Forty Global Oilfields Using a Detailed Engineering-Based Model of Oil Production

    Science.gov (United States)

    Brandt, Adam R.; Sun, Yuchi; Bharadwaj, Sharad; Livingston, David; Tan, Eugene; Gordon, Deborah

    2015-01-01

    Studies of the energy return on investment (EROI) for oil production generally rely on aggregated statistics for large regions or countries. In order to better understand the drivers of the energy productivity of oil production, we use a novel approach that applies a detailed field-level engineering model of oil and gas production to estimate energy requirements of drilling, producing, processing, and transporting crude oil. We examine 40 global oilfields, utilizing detailed data for each field from hundreds of technical and scientific data sources. Resulting net energy return (NER) ratios for studied oil fields range from ≈2 to ≈100 MJ crude oil produced per MJ of total fuels consumed. External energy return (EER) ratios, which compare energy produced to energy consumed from external sources, exceed 1000:1 for fields that are largely self-sufficient. The lowest energy returns are found to come from thermally-enhanced oil recovery technologies. Results are generally insensitive to reasonable ranges of assumptions explored in sensitivity analysis. Fields with very large associated gas production are sensitive to assumptions about surface fluids processing due to the shifts in energy consumed under different gas treatment configurations. This model does not currently include energy invested in building oilfield capital equipment (e.g., drilling rigs), nor does it include other indirect energy uses such as labor or services. PMID:26695068

  14. Energy Return on Investment (EROI for Forty Global Oilfields Using a Detailed Engineering-Based Model of Oil Production.

    Directory of Open Access Journals (Sweden)

    Adam R Brandt

    Full Text Available Studies of the energy return on investment (EROI for oil production generally rely on aggregated statistics for large regions or countries. In order to better understand the drivers of the energy productivity of oil production, we use a novel approach that applies a detailed field-level engineering model of oil and gas production to estimate energy requirements of drilling, producing, processing, and transporting crude oil. We examine 40 global oilfields, utilizing detailed data for each field from hundreds of technical and scientific data sources. Resulting net energy return (NER ratios for studied oil fields range from ≈2 to ≈100 MJ crude oil produced per MJ of total fuels consumed. External energy return (EER ratios, which compare energy produced to energy consumed from external sources, exceed 1000:1 for fields that are largely self-sufficient. The lowest energy returns are found to come from thermally-enhanced oil recovery technologies. Results are generally insensitive to reasonable ranges of assumptions explored in sensitivity analysis. Fields with very large associated gas production are sensitive to assumptions about surface fluids processing due to the shifts in energy consumed under different gas treatment configurations. This model does not currently include energy invested in building oilfield capital equipment (e.g., drilling rigs, nor does it include other indirect energy uses such as labor or services.

  15. Energy Return on Investment (EROI) for Forty Global Oilfields Using a Detailed Engineering-Based Model of Oil Production.

    Science.gov (United States)

    Brandt, Adam R; Sun, Yuchi; Bharadwaj, Sharad; Livingston, David; Tan, Eugene; Gordon, Deborah

    2015-01-01

    Studies of the energy return on investment (EROI) for oil production generally rely on aggregated statistics for large regions or countries. In order to better understand the drivers of the energy productivity of oil production, we use a novel approach that applies a detailed field-level engineering model of oil and gas production to estimate energy requirements of drilling, producing, processing, and transporting crude oil. We examine 40 global oilfields, utilizing detailed data for each field from hundreds of technical and scientific data sources. Resulting net energy return (NER) ratios for studied oil fields range from ≈2 to ≈100 MJ crude oil produced per MJ of total fuels consumed. External energy return (EER) ratios, which compare energy produced to energy consumed from external sources, exceed 1000:1 for fields that are largely self-sufficient. The lowest energy returns are found to come from thermally-enhanced oil recovery technologies. Results are generally insensitive to reasonable ranges of assumptions explored in sensitivity analysis. Fields with very large associated gas production are sensitive to assumptions about surface fluids processing due to the shifts in energy consumed under different gas treatment configurations. This model does not currently include energy invested in building oilfield capital equipment (e.g., drilling rigs), nor does it include other indirect energy uses such as labor or services.

  16. Engineering sustainable ecosystems: using GIS-based habitat modeling for oil sands mine reclamation and closure planning

    International Nuclear Information System (INIS)

    Seel, K.

    1997-01-01

    A GIS model was built to predict the climax vegetation habitat types on reclaimed mine surfaces in the Fort McMurray region of the Mid-Boreal Mixedwood Ecoregion of northwestern Alberta. Regional vegetation habitat types were classified by digital remote sensing using Landsat Thematic Mapper satellite data. Terrain data was derived from a high-resolution digital elevation model. The validated model was applied to the GIS database of Syncrude Canada's Mildred Lake Mine to predict future vegetation patterns based on the final closure mine surface. The results were compared to revegetation and closure plans created by experts to analyze performance and sustainability of reclamation efforts

  17. Analysis on the heating performance of a gas engine driven air to water heat pump based on a steady-state model

    International Nuclear Information System (INIS)

    Zhang, R.R.; Lu, X.S.; Li, S.Z.; Lin, W.S.; Gu, A.Z.

    2005-01-01

    In this study, the heating performance of a gas engine driven air to water heat pump was analyzed using a steady state model. The thermodynamic model of a natural gas engine is identified by the experimental data and the compressor model is created by several empirical equations. The heat exchanger models are developed by the theory of heat balance. The system model is validated by comparing the experimental and simulation data, which shows good agreement. To understand the heating characteristic in detail, the performance of the system is analyzed in a wide range of operating conditions, and especially the effect of engine waste heat on the heating performance is discussed. The results show that engine waste heat can provide about 1/3 of the total heating capacity in this gas engine driven air to water heat pump. The performance of the engine, heat pump and integral system are analyzed under variations of engine speed and ambient temperature. It shows that engine speed has remarkable effects on both the engine and heat pump, but ambient temperature has little influence on the engine's performance. The system and component performances in variable speed operating conditions is also discussed at the end of the paper

  18. Wheels, Cranks, and Cams: An Animated Spreadsheet-Based Mathematical Model of a Four-Stroke Engine.

    Science.gov (United States)

    Callender, J. T.; Jackson, R.

    1998-01-01

    Analyzes the mathematics of rotational and translational motion and how one can influence the other in the context of cams and cranks. Describes how the individual components can be brought together to simulate a four-stroke engine and how the engine animates again using the same simple macro. (Author/ASK)

  19. Engineering spinal fusion: evaluating ceramic materials for cell based tissue engineered approaches

    NARCIS (Netherlands)

    Wilson, C.E.

    2011-01-01

    The principal aim of this thesis was to advance the development of tissue engineered posterolateral spinal fusion by investigating the potential of calcium phosphate ceramic materials to support cell based tissue engineered bone formation. This was accomplished by developing several novel model

  20. Gade4all: Developing Multi-platform Videogames based on Domain Specific Languages and Model Driven Engineering

    Directory of Open Access Journals (Sweden)

    Edward Rolando Nuñez-Valdez

    2013-06-01

    Full Text Available The development of applications for mobile devices is a constantly growing market which and more and more enterprises support the development of applications for this kind of devices. In that sense, videogames for mobile devices have become very popular worldwide and are now part of highly profitable and competitive industry. Due to the diversity of platforms and mobile devices and the complexity of this kind of applications, the development time and the number of errors within that development process have increased. The productivity of the developers has also decreased due to the necessity of using many programming languages in the development process. One of the most popular strategies is to employ specialized people to perform the development tasks more efficiently, but this involves an increase of the costs, which makes some applications economically unviable. In this article we present the Gade4all Project, consisting in a new platform that aims to facilitate the development of videogames and entertainment software through the use of Domain Specific Languages and Model Driven Engineering. This tool makes possible for users without previous knowledge in the field of software development to create 2D videogames for multiplatform mobile devices in a simple and innovative way.

  1. Philosophical analysis of models of engineering education in Russia

    Directory of Open Access Journals (Sweden)

    Fadeeva V. N.

    2016-01-01

    Full Text Available This article defines the principles of the philosophical approach to the problems of engineering education. Ontological, epistemological and axiological components of the proposed approach are distinguished. Assessment criteria of engineering education models are specified. Basing on the presented principles and criteria, the analysis of Russian engineering education models is performed. The authors distinguish the following models: classical (tsarism, soviet transitional, soviet industrial, physicotechnical model, soviet mass (reproductive and Russian transitional models. In addition among developing models it is possible to recognize the following ones: methodological (creative and outrunning (advanced models. On the basis of the performed analysis, positive and negative aspects of the distinguished models are determined, and, it is possible to make a conclusion that every accomplished model emergence was reasoned by particular issues raised in the state at the particular period of time. The talking point of the necessity to design a proactive model of engineering education is formulated.

  2. An Exploratory Study of Cost Engineering in Axiomatic Design: Creation of the Cost Model Based on an FR-DP Map

    Science.gov (United States)

    Lee, Taesik; Jeziorek, Peter

    2004-01-01

    Large complex projects cost large sums of money throughout their life cycle for a variety of reasons and causes. For such large programs, the credible estimation of the project cost, a quick assessment of the cost of making changes, and the management of the project budget with effective cost reduction determine the viability of the project. Cost engineering that deals with these issues requires a rigorous method and systematic processes. This paper introduces a logical framework to a&e effective cost engineering. The framework is built upon Axiomatic Design process. The structure in the Axiomatic Design process provides a good foundation to closely tie engineering design and cost information together. The cost framework presented in this paper is a systematic link between the functional domain (FRs), physical domain (DPs), cost domain (CUs), and a task/process-based model. The FR-DP map relates a system s functional requirements to design solutions across all levels and branches of the decomposition hierarchy. DPs are mapped into CUs, which provides a means to estimate the cost of design solutions - DPs - from the cost of the physical entities in the system - CUs. The task/process model describes the iterative process ot-developing each of the CUs, and is used to estimate the cost of CUs. By linking the four domains, this framework provides a superior traceability from requirements to cost information.

  3. Aircraft Engine Thrust Estimator Design Based on GSA-LSSVM

    Science.gov (United States)

    Sheng, Hanlin; Zhang, Tianhong

    2017-08-01

    In view of the necessity of highly precise and reliable thrust estimator to achieve direct thrust control of aircraft engine, based on support vector regression (SVR), as well as least square support vector machine (LSSVM) and a new optimization algorithm - gravitational search algorithm (GSA), by performing integrated modelling and parameter optimization, a GSA-LSSVM-based thrust estimator design solution is proposed. The results show that compared to particle swarm optimization (PSO) algorithm, GSA can find unknown optimization parameter better and enables the model developed with better prediction and generalization ability. The model can better predict aircraft engine thrust and thus fulfills the need of direct thrust control of aircraft engine.

  4. Semoogle - An Ontology Based Search Engine

    OpenAIRE

    Aghajani, Nooshin

    2012-01-01

    In this thesis, we present a prototype for search engine to show how such a semantic search application based on ontology techniques contributes to save time for user, and improve the quality of relevant search results compared to a traditional search engine. This system is built as a query improvement module, which uses ontology and sorts the results search based on four predefined categories. The first and important part of the implementation of search engine prototype is to apply ontology ...

  5. Performing Verification and Validation in Reuse-Based Software Engineering

    Science.gov (United States)

    Addy, Edward A.

    1999-01-01

    The implementation of reuse-based software engineering not only introduces new activities to the software development process, such as domain analysis and domain modeling, it also impacts other aspects of software engineering. Other areas of software engineering that are affected include Configuration Management, Testing, Quality Control, and Verification and Validation (V&V). Activities in each of these areas must be adapted to address the entire domain or product line rather than a specific application system. This paper discusses changes and enhancements to the V&V process, in order to adapt V&V to reuse-based software engineering.

  6. Modeling of hybrid vehicle fuel economy and fuel engine efficiency

    Science.gov (United States)

    Wu, Wei

    "Near-CV" (i.e., near-conventional vehicle) hybrid vehicles, with an internal combustion engine, and a supplementary storage with low-weight, low-energy but high-power capacity, are analyzed. This design avoids the shortcoming of the "near-EV" and the "dual-mode" hybrid vehicles that need a large energy storage system (in terms of energy capacity and weight). The small storage is used to optimize engine energy management and can provide power when needed. The energy advantage of the "near-CV" design is to reduce reliance on the engine at low power, to enable regenerative braking, and to provide good performance with a small engine. The fuel consumption of internal combustion engines, which might be applied to hybrid vehicles, is analyzed by building simple analytical models that reflect the engines' energy loss characteristics. Both diesel and gasoline engines are modeled. The simple analytical models describe engine fuel consumption at any speed and load point by describing the engine's indicated efficiency and friction. The engine's indicated efficiency and heat loss are described in terms of several easy-to-obtain engine parameters, e.g., compression ratio, displacement, bore and stroke. Engine friction is described in terms of parameters obtained by fitting available fuel measurements on several diesel and spark-ignition engines. The engine models developed are shown to conform closely to experimental fuel consumption and motored friction data. A model of the energy use of "near-CV" hybrid vehicles with different storage mechanism is created, based on simple algebraic description of the components. With powertrain downsizing and hybridization, a "near-CV" hybrid vehicle can obtain a factor of approximately two in overall fuel efficiency (mpg) improvement, without considering reductions in the vehicle load.

  7. 76 FR 56637 - Airworthiness Directives; Lycoming Engines Model IO-720-A1B Reciprocating Engines

    Science.gov (United States)

    2011-09-14

    ... Airworthiness Directives; Lycoming Engines Model IO-720-A1B Reciprocating Engines AGENCY: Federal Aviation... directive (AD) for certain model IO-720-A1B Lycoming Engines reciprocating engines. This AD requires a... two Lycoming Engines model IO- 720-A1B reciprocating engines, installed on airplanes of U.S. registry...

  8. Model for fracture mechanics based prediction of the fatigue strength of engineering alloys containing microscopical initial defects

    Directory of Open Access Journals (Sweden)

    Zerbst Uwe

    2014-06-01

    Full Text Available Recently two of the authors of the present paper proposed a model for fracture mechanics based prediction of the S-N characteristics of metallic components with large microstructural defects and supported this by a validation excercise on an aluminium alloy AL5380 H321. Within this presentation the authors extend the study using a number of data sets from the literature. Despite of necessary assumptions for the compensation of partially missing input information the results are fairly reasonable, with the exception of high loading levels where the analyses of two of the data sets yield non-conservative results. The authors propose multiple crack initiation as the potential root of the problem and discuss methods for extending the model for taking into account crack initiation.

  9. Mean Value Modelling of Turbocharged SI Engines

    DEFF Research Database (Denmark)

    Müller, Martin; Hendricks, Elbert; Sorenson, Spencer C.

    1998-01-01

    The development of a computer simulation to predict the performance of a turbocharged spark ignition engine during transient operation. New models have been developed for the turbocharged and the intercooling system. An adiabatic model for the intake manifold is presented.......The development of a computer simulation to predict the performance of a turbocharged spark ignition engine during transient operation. New models have been developed for the turbocharged and the intercooling system. An adiabatic model for the intake manifold is presented....

  10. A Plastic Damage Mechanics Model for Engineered Cementitious Composites

    DEFF Research Database (Denmark)

    Dick-Nielsen, Lars; Stang, Henrik; Poulsen, Peter Noe

    2007-01-01

    This paper discusses the establishment of a plasticity-based damage mechanics model for Engineered Cementitious Composites (ECC). The present model differs from existing models by combining a matrix and fiber description in order to describe the behavior of the ECC material. The model provides...

  11. Optimization in engineering models and algorithms

    CERN Document Server

    Sioshansi, Ramteen

    2017-01-01

    This textbook covers the fundamentals of optimization, including linear, mixed-integer linear, nonlinear, and dynamic optimization techniques, with a clear engineering focus. It carefully describes classical optimization models and algorithms using an engineering problem-solving perspective, and emphasizes modeling issues using many real-world examples related to a variety of application areas. Providing an appropriate blend of practical applications and optimization theory makes the text useful to both practitioners and students, and gives the reader a good sense of the power of optimization and the potential difficulties in applying optimization to modeling real-world systems. The book is intended for undergraduate and graduate-level teaching in industrial engineering and other engineering specialties. It is also of use to industry practitioners, due to the inclusion of real-world applications, opening the door to advanced courses on both modeling and algorithm development within the industrial engineering ...

  12. Mathematical model of the Amazon Stirling engine

    Energy Technology Data Exchange (ETDEWEB)

    Vidal Medina, Juan Ricardo [Universidad Autonoma de Occidente (Colombia)], e-mail: jrvidal@uao.edu.co; Cobasa, Vladimir Melian; Silva, Electo [Universidade Federal de Itajuba, MG (Brazil)], e-mail: vlad@unifei.edu.br

    2010-07-01

    The Excellency Group in Thermoelectric and Distributed Generation (NEST, for its acronym in Portuguese) at the Federal University of Itajuba, has designed a Stirling engine prototype to provide electricity to isolated regions of Brazil. The engine was designed to operate with residual biomass from timber process. This paper presents mathematical models of heat exchangers (hot, cold and regenerator) integrated into second order adiabatic models. The general model takes into account the pressure drop losses, hysteresis and internal losses. The results of power output, engine efficiency, optimal velocity of the exhaust gases and the influence of dead volume in engine efficiency are presented in this paper. The objective of this modeling is to propose improvements to the manufactured engine design. (author)

  13. Novel Model-Based Inquiry of Ionic Bonding in Alginate Hydrogels Used in Tissue Engineering for High School Students

    Science.gov (United States)

    Bowles, Robby D.; Saroka, James M.; Archer, Shivaun D.; Bonassar, Lawrence J.

    2012-01-01

    Because of cost and time, it is difficult to relate to students how fundamental chemical principles are involved in cutting edge biomedical breakthroughs being reported in the national media. The laboratory exercise presented here is aimed at high school chemistry students and uses alginate hydrogels, a common material used in tissue engineering,…

  14. Academic program models for undergraduate biomedical engineering.

    Science.gov (United States)

    Krishnan, Shankar M

    2014-01-01

    There is a proliferation of medical devices across the globe for the diagnosis and therapy of diseases. Biomedical engineering (BME) plays a significant role in healthcare and advancing medical technologies thus creating a substantial demand for biomedical engineers at undergraduate and graduate levels. There has been a surge in undergraduate programs due to increasing demands from the biomedical industries to cover many of their segments from bench to bedside. With the requirement of multidisciplinary training within allottable duration, it is indeed a challenge to design a comprehensive standardized undergraduate BME program to suit the needs of educators across the globe. This paper's objective is to describe three major models of undergraduate BME programs and their curricular requirements, with relevant recommendations to be applicable in institutions of higher education located in varied resource settings. Model 1 is based on programs to be offered in large research-intensive universities with multiple focus areas. The focus areas depend on the institution's research expertise and training mission. Model 2 has basic segments similar to those of Model 1, but the focus areas are limited due to resource constraints. In this model, co-op/internship in hospitals or medical companies is included which prepares the graduates for the work place. In Model 3, students are trained to earn an Associate Degree in the initial two years and they are trained for two more years to be BME's or BME Technologists. This model is well suited for the resource-poor countries. All three models must be designed to meet applicable accreditation requirements. The challenges in designing undergraduate BME programs include manpower, facility and funding resource requirements and time constraints. Each academic institution has to carefully analyze its short term and long term requirements. In conclusion, three models for BME programs are described based on large universities, colleges, and

  15. Proceedings of the 2012 Model-Based Systems Engineering Symposium, 27 - 28 November 2012, DSTO Edinburgh, South Australia

    Science.gov (United States)

    2013-02-01

    Australia, Asia and Europe, including Mitsubishi Motors, Ford and Caterpillar . He currently works for Aerospace Concepts, a systems engineering consulting...understanding of military SoS in terms of its variety, formation, evolution and complexity; 2) an understanding of SoS activities throughout lifecycles and...in evolution ; 3) potential roles of MBSE in and relation to SoSE practice; and 4) key challenges and opportunities for applications of MBSE for

  16. A genetically engineered ovarian cancer mouse model based on fallopian tube transformation mimics human high-grade serous carcinoma development.

    Science.gov (United States)

    Sherman-Baust, Cheryl A; Kuhn, Elisabetta; Valle, Blanca L; Shih, Ie-Ming; Kurman, Robert J; Wang, Tian-Li; Amano, Tomokazu; Ko, Minoru S H; Miyoshi, Ichiro; Araki, Yoshihiko; Lehrmann, Elin; Zhang, Yongqing; Becker, Kevin G; Morin, Patrice J

    2014-07-01

    Recent evidence suggests that ovarian high-grade serous carcinoma (HGSC) originates from the epithelium of the fallopian tube. However, most mouse models are based on the previous prevailing view that ovarian cancer develops from the transformation of the ovarian surface epithelium. Here, we report the extensive histological and molecular characterization of the mogp-TAg transgenic mouse, which expresses the SV40 large T-antigen (TAg) under the control of the mouse müllerian-specific Ovgp-1 promoter. Histological analysis of the fallopian tubes of mogp-TAg mice identified a variety of neoplastic lesions analogous to those described as precursors to ovarian HGSC. We identified areas of normal-appearing p53-positive epithelium that are similar to 'p53 signatures' in the human fallopian tube. More advanced proliferative lesions with nuclear atypia and epithelial stratification were also identified that were morphologically and immunohistochemically reminiscent of human serous tubal intraepithelial carcinoma (STIC), a potential precursor of ovarian HGSC. Beside these non-invasive precursor lesions, we also identified invasive adenocarcinoma in the ovaries of 56% of the mice. Microarray analysis revealed several genes differentially expressed between the fallopian tube of mogp-TAg and wild-type (WT) C57BL/6. One of these genes, Top2a, which encodes topoisomerase IIα, was shown by immunohistochemistry to be concurrently expressed with elevated p53 and was specifically elevated in mouse STICs but not in the surrounding tissues. TOP2A protein was also found elevated in human STICs, low-grade and high-grade serous carcinoma. The mouse model reported here displays a progression from normal tubal epithelium to invasive HGSC in the ovary, and therefore closely simulates the current emerging model of human ovarian HGSC pathogenesis. This mouse therefore has the potential to be a very useful new model for elucidating the mechanisms of serous ovarian tumourigenesis, as well as

  17. Web-based education in bioprocess engineering

    NARCIS (Netherlands)

    Sessink, O.D.T.; Schaaf, van der H.; Beeftink, H.H.; Hartog, R.; Tramper, J.

    2007-01-01

    The combination of web technology, knowledge of bioprocess engineering, and theories on learning and instruction might yield innovative learning material for bioprocess engineering. In this article, an overview of the characteristics of web-based learning material is given, as well as guidelines for

  18. Measuring Model Rocket Engine Thrust Curves

    Science.gov (United States)

    Penn, Kim; Slaton, William V.

    2010-01-01

    This paper describes a method and setup to quickly and easily measure a model rocket engine's thrust curve using a computer data logger and force probe. Horst describes using Vernier's LabPro and force probe to measure the rocket engine's thrust curve; however, the method of attaching the rocket to the force probe is not discussed. We show how a…

  19. Toward design-based engineering of industrial microbes.

    Science.gov (United States)

    Tyo, Keith E J; Kocharin, Kanokarn; Nielsen, Jens

    2010-06-01

    Engineering industrial microbes has been hampered by incomplete knowledge of cell biology. Thus an iterative engineering cycle of modeling, implementation, and analysis has been used to increase knowledge of the underlying biology while achieving engineering goals. Recent advances in Systems Biology technologies have drastically improved the amount of information that can be collected in each iteration. As well, Synthetic Biology tools are melding modeling and molecular implementation. These advances promise to move microbial engineering from the iterative approach to a design-oriented paradigm, similar to electrical circuits and architectural design. Genome-scale metabolic models, new tools for controlling expression, and integrated -omics analysis are described as key contributors in moving the field toward Design-based Engineering. Copyright 2010 Elsevier Ltd. All rights reserved.

  20. [STUDY OF HUMORAL IMMUNE RESPONSE FEATURES BASED ON MODELLING OF ANTIGEN DETERMINANTS OF HEPATITIS C VIRUS BY SYNTHETIC PEPTIDES AND GENETICALLY ENGINEERED POLYPEPTIDES].

    Science.gov (United States)

    Kruglov, I V

    2015-01-01

    Study of humoral immune response features in patients with acute hepatitis C (AHC) with various disease outcomes based on modelling of antigen determinants of hepatitis C virus (HCV) by synthetic peptides and genetically engineered polypeptides. 20 patients with icteric form of AHC based on clinical-biochemical presentation and HCV RNA detection by PCR in blood sera during 12 months from the disease onset were included into the study. Antibody seroconversion study was carried out by EIA. Genetically engineered proteins and synthetic peptides were used as antigens. Similarity and differences of humoral immune response against the HCV antigens used in this study depending on the disease outcome (convalescence or chronicity) were shown. Significant difference of the humoral immune response to both HCV core protein and various fragments of the immune dominant region of this protein were detected, that indicates on a link of these features of immune response with perspectives of a more or less favorable disease development. The regularities of seroconversion detected allow to consider anti-NS5 IgG as a prognostic marker of the disease chronicity. Such marker, as anti-NS3 IgG, is important for diagnostics, but not for disease outcome prognosis.

  1. Evaluating Quality in Model-Driven Engineering

    OpenAIRE

    Mohagheghi, Parastoo; Aagedal, Jan

    2007-01-01

    In Model-Driven Engineering (MDE), models are the prime artifacts, and developing high-quality systems depends on developing high-quality models and performing transformations that preserve quality or even improve it. This paper presents quality goals in MDE and states that the quality of models is affected by the quality of modeling languages, tools, modeling processes, the knowledge and experience of modelers, and the quality assurance techniques applied. The paper further presents related ...

  2. Automated Model Fit Method for Diesel Engine Control Development

    NARCIS (Netherlands)

    Seykens, X.; Willems, F.P.T.; Kuijpers, B.; Rietjens, C.

    2014-01-01

    This paper presents an automated fit for a control-oriented physics-based diesel engine combustion model. This method is based on the combination of a dedicated measurement procedure and structured approach to fit the required combustion model parameters. Only a data set is required that is

  3. Enhanced thermodynamic modelling of a gamma-type Stirling engine

    International Nuclear Information System (INIS)

    Alfarawi, S.; AL-Dadah, R.; Mahmoud, S.

    2016-01-01

    Highlights: • Enhanced thermodynamic model for gamma-type Stirling engine was developed. • Validation against experiments was performed. • Influence of different parameters on engine performance was investigated. • Deeper insight into engine improvements was highlighted. • Effect of low temperature cooling on engine performance was addressed. - Abstract: Modelling can substantially contribute to the development of Stirling engines technology and help understanding the fundamental processes of the real cycle for further performance improvement. In the present work, an enhanced thermodynamic model for Gamma-type Stirling engine simulation was developed based on the reconfiguration of non-ideal adiabatic analysis. The developed model was validated against experimental measurements on Stirling engine prototype (ST05 CNC), available at University of Birmingham. Good agreement was found between the model and experiment in predicting the indicated power, shaft power and thermal efficiency at different operating conditions. A parametric study was carried out to investigate the effect of phase angle, gas type, regenerator matrix type and dead volume on engine performance. The feasibility of utilizing the stored cold energy of LN2 to maximize the shaft power was also presented. Results showed that shaft power can be significantly enhanced by 49% for helium and 35% for nitrogen when cooling temperature is lowered to −50 °C while heating temperature remains constant at 650 °C.

  4. 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.

  5. Numerical methods and modelling for engineering

    CERN Document Server

    Khoury, Richard

    2016-01-01

    This textbook provides a step-by-step approach to numerical methods in engineering modelling. The authors provide a consistent treatment of the topic, from the ground up, to reinforce for students that numerical methods are a set of mathematical modelling tools which allow engineers to represent real-world systems and compute features of these systems with a predictable error rate. Each method presented addresses a specific type of problem, namely root-finding, optimization, integral, derivative, initial value problem, or boundary value problem, and each one encompasses a set of algorithms to solve the problem given some information and to a known error bound. The authors demonstrate that after developing a proper model and understanding of the engineering situation they are working on, engineers can break down a model into a set of specific mathematical problems, and then implement the appropriate numerical methods to solve these problems. Uses a “building-block” approach, starting with simpler mathemati...

  6. Statistical models of petrol engines vehicles dynamics

    Science.gov (United States)

    Ilie, C. O.; Marinescu, M.; Alexa, O.; Vilău, R.; Grosu, D.

    2017-10-01

    This paper focuses on studying statistical models of vehicles dynamics. It was design and perform a one year testing program. There were used many same type cars with gasoline engines and different mileage. Experimental data were collected of onboard sensors and those on the engine test stand. A database containing data of 64th tests was created. Several mathematical modelling were developed using database and the system identification method. Each modelling is a SISO or a MISO linear predictive ARMAX (AutoRegressive-Moving-Average with eXogenous inputs) model. It represents a differential equation with constant coefficients. It were made 64th equations for each dependency like engine torque as output and engine’s load and intake manifold pressure, as inputs. There were obtained strings with 64 values for each type of model. The final models were obtained using average values of the coefficients. The accuracy of models was assessed.

  7. Updating the U.S. Life Cycle GHG Petroleum Baseline to 2014 with Projections to 2040 Using Open-Source Engineering-Based Models.

    Science.gov (United States)

    Cooney, Gregory; Jamieson, Matthew; Marriott, Joe; Bergerson, Joule; Brandt, Adam; Skone, Timothy J

    2017-01-17

    The National Energy Technology Laboratory produced a well-to-wheels (WTW) life cycle greenhouse gas analysis of petroleum-based fuels consumed in the U.S. in 2005, known as the NETL 2005 Petroleum Baseline. This study uses a set of engineering-based, open-source models combined with publicly available data to calculate baseline results for 2014. An increase between the 2005 baseline and the 2014 results presented here (e.g., 92.4 vs 96.2 g CO 2 e/MJ gasoline, + 4.1%) are due to changes both in modeling platform and in the U.S. petroleum sector. An updated result for 2005 was calculated to minimize the effect of the change in modeling platform, and emissions for gasoline in 2014 were about 2% lower than in 2005 (98.1 vs 96.2 g CO 2 e/MJ gasoline). The same methods were utilized to forecast emissions from fuels out to 2040, indicating maximum changes from the 2014 gasoline result between +2.1% and -1.4%. The changing baseline values lead to potential compliance challenges with frameworks such as the Energy Independence and Security Act (EISA) Section 526, which states that Federal agencies should not purchase alternative fuels unless their life cycle GHG emissions are less than those of conventionally produced, petroleum-derived fuels.

  8. Learning to Model in Engineering

    Science.gov (United States)

    Gainsburg, Julie

    2013-01-01

    Policymakers and education scholars recommend incorporating mathematical modeling into mathematics education. Limited implementation of modeling instruction in schools, however, has constrained research on how students learn to model, leaving unresolved debates about whether modeling should be reified and explicitly taught as a competence, whether…

  9. Exploring the Integration of COSYSMO with a Model-Based Systems Engineering Methodology in Early Trade Space Analytics and Decisions

    Science.gov (United States)

    2016-06-01

    methodology , analysis, and recommendations that appear in Chapters 3-5. 2.1 Major Defense Acquisition Programs: The Big Ticket Items Major defense...Chapter Summary: Methodology This chapter identifies and discusses the specific SysML models, data requirements, and model entities that relate to the...The background, methodology , and results presented in this thesis highlighted themes of compliance, use of system models, data utility, and an

  10. Software Engineering Laboratory (SEL) cleanroom process model

    Science.gov (United States)

    Green, Scott; Basili, Victor; Godfrey, Sally; Mcgarry, Frank; Pajerski, Rose; Waligora, Sharon

    1991-01-01

    The Software Engineering Laboratory (SEL) cleanroom process model is described. The term 'cleanroom' originates in the integrated circuit (IC) production process, where IC's are assembled in dust free 'clean rooms' to prevent the destructive effects of dust. When applying the clean room methodology to the development of software systems, the primary focus is on software defect prevention rather than defect removal. The model is based on data and analysis from previous cleanroom efforts within the SEL and is tailored to serve as a guideline in applying the methodology to future production software efforts. The phases that are part of the process model life cycle from the delivery of requirements to the start of acceptance testing are described. For each defined phase, a set of specific activities is discussed, and the appropriate data flow is described. Pertinent managerial issues, key similarities and differences between the SEL's cleanroom process model and the standard development approach used on SEL projects, and significant lessons learned from prior cleanroom projects are presented. It is intended that the process model described here will be further tailored as additional SEL cleanroom projects are analyzed.

  11. Model-driven and software product line engineering

    CERN Document Server

    Royer, Jean-Claude

    2013-01-01

    Many approaches to creating Software Product Lines have emerged that are based on Model-Driven Engineering. This book introduces both Software Product Lines and Model-Driven Engineering, which have separate success stories in industry, and focuses on the practical combination of them. It describes the challenges and benefits of merging these two software development trends and provides the reader with a novel approach and practical mechanisms to improve software development productivity.The book is aimed at engineers and students who wish to understand and apply software product lines

  12. Semantic modeling and interoperability in product and process engineering a technology for engineering informatics

    CERN Document Server

    2013-01-01

    In the past decade, feature-based design and manufacturing has gained some momentum in various engineering domains to represent and reuse semantic patterns with effective applicability. However, the actual scope of feature application is still very limited. Semantic Modeling and Interoperability in Product and Process Engineering provides a systematic solution for the challenging engineering informatics field aiming at the enhancement of sustainable knowledge representation, implementation and reuse in an open and yet practically manageable scale.   This semantic modeling technology supports uniform, multi-facet and multi-level collaborative system engineering with heterogeneous computer-aided tools, such as CADCAM, CAE, and ERP.  This presented unified feature model can be applied to product and process representation, development, implementation and management. Practical case studies and test samples are provided to illustrate applications which can be implemented by the readers in real-world scenarios. �...

  13. Reverse engineering of the robot base platform

    International Nuclear Information System (INIS)

    Anwar A Rahman; Azizul Rahman A Aziz; Mohd Arif Hamzah; Muhd Nor Atan; Fadil Ismail; Rosli Darmawan

    2009-01-01

    The robot base platform used to place the robotic arm version 2 was imported through a local company. The robot base platform is used as a reference for reverse egineering development for a smaller size robot. The paper will discuss the reverse engineering design process and parameters involved in the development of the robot base platform. (Author)

  14. Combustion modeling in internal combustion engines

    Science.gov (United States)

    Zeleznik, F. J.

    1976-01-01

    The fundamental assumptions of the Blizard and Keck combustion model for internal combustion engines are examined and a generalization of that model is derived. The most significant feature of the model is that it permits the occurrence of unburned hydrocarbons in the thermodynamic-kinetic modeling of exhaust gases. The general formulas are evaluated in two specific cases that are likely to be significant in the applications of the model.

  15. ZMOTTO- MODELING THE INTERNAL COMBUSTION ENGINE

    Science.gov (United States)

    Zeleznik, F. J.

    1994-01-01

    The ZMOTTO program was developed to model mathematically a spark-ignited internal combustion engine. ZMOTTO is a large, general purpose program whose calculations can be established at five levels of sophistication. These five models range from an ideal cycle requiring only thermodynamic properties, to a very complex representation demanding full combustion kinetics, transport properties, and poppet valve flow characteristics. ZMOTTO is a flexible and computationally economical program based on a system of ordinary differential equations for cylinder-averaged properties. The calculations assume that heat transfer is expressed in terms of a heat transfer coefficient and that the cylinder average of kinetic plus potential energies remains constant. During combustion, the pressures of burned and unburned gases are assumed equal and their heat transfer areas are assumed proportional to their respective mass fractions. Even the simplest ZMOTTO model provides for residual gas effects, spark advance, exhaust gas recirculation, supercharging, and throttling. In the more complex models, 1) finite rate chemistry replaces equilibrium chemistry in descriptions of both the flame and the burned gases, 2) poppet valve formulas represent fluid flow instead of a zero pressure drop flow, and 3) flame propagation is modeled by mass burning equations instead of as an instantaneous process. Input to ZMOTTO is determined by the model chosen. Thermodynamic data is required for all models. Transport properties and chemical kinetics data are required only as the model complexity grows. Other input includes engine geometry, working fluid composition, operating characteristics, and intake/exhaust data. ZMOTTO accommodates a broad spectrum of reactants. The program will calculate many Otto cycle performance parameters for a number of consecutive cycles (a cycle being an interval of 720 crankangle degrees). A typical case will have a number of initial ideal cycles and progress through levels

  16. Mathematical Modeling of Hybrid Electrical Engineering Systems

    Directory of Open Access Journals (Sweden)

    A. A. Lobaty

    2016-01-01

    Full Text Available A large class of systems that have found application in various industries and households, electrified transportation facilities and energy sector has been classified as electrical engineering systems. Their characteristic feature is a combination of continuous and discontinuous modes of operation, which is reflected in the appearance of a relatively new term “hybrid systems”. A wide class of hybrid systems is pulsed DC converters operating in a pulse width modulation, which are non-linear systems with variable structure. Using various methods for linearization it is possible to obtain linear mathematical models that rather accurately simulate behavior of such systems. However, the presence in the mathematical models of exponential nonlinearities creates considerable difficulties in the implementation of digital hardware. The solution can be found while using an approximation of exponential functions by polynomials of the first order, that, however, violates the rigor accordance of the analytical model with characteristics of a real object. There are two practical approaches to synthesize algorithms for control of hybrid systems. The first approach is based on the representation of the whole system by a discrete model which is described by difference equations that makes it possible to synthesize discrete algorithms. The second approach is based on description of the system by differential equations. The equations describe synthesis of continuous algorithms and their further implementation in a digital computer included in the control loop system. The paper considers modeling of a hybrid electrical engineering system using differential equations. Neglecting the pulse duration, it has been proposed to describe behavior of vector components in phase coordinates of the hybrid system by stochastic differential equations containing generally non-linear differentiable random functions. A stochastic vector-matrix equation describing dynamics of the

  17. Development and evaluation of a digital dental modeling method based on grating projection and reverse engineering software.

    Science.gov (United States)

    Zhou, Qin; Wang, Zhenzhen; Chen, Jun; Song, Jun; Chen, Lu; Lu, Yi

    2016-01-01

    For reasons of convenience and economy, attempts have been made to transform traditional dental gypsum casts into 3-dimensional (3D) digital casts. Different scanning devices have been developed to generate digital casts; however, each has its own limitations and disadvantages. The purpose of this study was to develop an advanced method for the 3D reproduction of dental casts by using a high-speed grating projection system and noncontact reverse engineering (RE) software and to evaluate the accuracy of the method. The methods consisted of 3 main steps: the scanning and acquisition of 3D dental cast data with a high-resolution grating projection system, the reconstruction and measurement of digital casts with RE software, and the evaluation of the accuracy of this method using 20 dental gypsum casts. The common anatomic landmarks were measured directly on the gypsum casts with a Vernier caliper and on the 3D digital casts with the Geomagic software measurement tool. Data were statistically assessed with the t test. The grating projection system had a rapid scanning speed, and smooth 3D dental casts were obtained. The mean differences between the gypsum and 3D measurements were approximately 0.05 mm, and no statistically significant differences were found between the 2 methods (P>.05), except for the measurements of the incisor tooth width and maxillary arch length. A method for the 3D reconstruction of dental casts was developed by using a grating projection system and RE software. The accuracy of the casts generated using the grating projection system was comparable with that of the gypsum casts. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  18. Finite Element Model to Analyze an Installation Load-based Stress-Strain State of the Parts Forming Gas Joint of a Medium-Speed Diesel Engine

    Directory of Open Access Journals (Sweden)

    N. D. Chainov

    2015-01-01

    Full Text Available The paper considers a developed computational model to study a stress-strain state of the assembly unit components of a medium-speed diesel engine of new generation, type CH26.5/31, which comprises a cylinder head, a sleeve, a gasket, a block, two mounting studs and four power studs.The developed three-dimensional finite element model presented in this article allows us to take into consideration all the components that make up a gas joint, regardless of their geometric complexity. Its use enables us to estimate the cylinder head - gasket - sleeve tightness of sealing when applying the mounting, temperature, and gas loads, to define the stress and strain components of parts, as well as to study the gasket condition, including pressure distribution across its surface.Based on the results obtained in the study the finite element model of the cylinder head was modified considering a more detailed description of its geometry, thus reducing the principal tensile stresses.

  19. Basic science through engineering? Synthetic modeling and the idea of biology-inspired engineering.

    Science.gov (United States)

    Knuuttila, Tarja; Loettgers, Andrea

    2013-06-01

    Synthetic biology is often understood in terms of the pursuit for well-characterized biological parts to create synthetic wholes. Accordingly, it has typically been conceived of as an engineering dominated and application oriented field. We argue that the relationship of synthetic biology to engineering is far more nuanced than that and involves a sophisticated epistemic dimension, as shown by the recent practice of synthetic modeling. Synthetic models are engineered genetic networks that are implanted in a natural cell environment. Their construction is typically combined with experiments on model organisms as well as mathematical modeling and simulation. What is especially interesting about this combinational modeling practice is that, apart from greater integration between these different epistemic activities, it has also led to the questioning of some central assumptions and notions on which synthetic biology is based. As a result synthetic biology is in the process of becoming more "biology inspired." Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. The Strutjet Rocket Based Combined Cycle Engine

    Science.gov (United States)

    Siebenhaar, A.; Bulman, M. J.; Bonnar, D. K.

    1998-01-01

    The multi stage chemical rocket has been established over many years as the propulsion System for space transportation vehicles, while, at the same time, there is increasing concern about its continued affordability and rather involved reusability. Two broad approaches to addressing this overall launch cost problem consist in one, the further development of the rocket motor, and two, the use of airbreathing propulsion to the maximum extent possible as a complement to the limited use of a conventional rocket. In both cases, a single-stage-to-orbit (SSTO) vehicle is considered a desirable goal. However, neither the "all-rocket" nor the "all-airbreathing" approach seems realizable and workable in practice without appreciable advances in materials and manufacturing. An affordable system must be reusable with minimal refurbishing on-ground, and large mean time between overhauls, and thus with high margins in design. It has been suggested that one may use different engine cycles, some rocket and others airbreathing, in a combination over a flight trajectory, but this approach does not lead to a converged solution with thrust-to-mass, specific impulse, and other performance and operational characteristics that can be obtained in the different engines. The reason is this type of engine is simply a combination of different engines with no commonality of gas flowpath or components, and therefore tends to have the deficiencies of each of the combined engines. A further development in this approach is a truly combined cycle that incorporates a series of cycles for different modes of propulsion along a flight path with multiple use of a set of components and an essentially single gas flowpath through the engine. This integrated approach is based on realizing the benefits of both a rocket engine and airbreathing engine in various combinations by a systematic functional integration of components in an engine class usually referred to as a rocket-based combined cycle (RBCC) engine

  1. Experiences with Formal Engineering : Model-Based Specification, Implementation and Testing of a Software Bus at Neopost

    NARCIS (Netherlands)

    Sijtema, Marten; Stoelinga, Mariëlle Ida Antoinette; Belinfante, Axel; Marinelli, Lawrence; Salaün, Gwen; Schätz, Bernhard

    We report on the actual industrial use of formal methods during the development of a software bus. At Neopost Inc., we developed the server component of a software bus, called the XBus, using formal methods during the design, validation and testing phase: We modeled our design of the XBus in the

  2. Systems Engineering Model for ART Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Mendez Cruz, Carmen Margarita [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rochau, Gary E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wilson, Mollye C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-02-01

    The near-term objective of the EC team is to establish an operating, commercially scalable Recompression Closed Brayton Cycle (RCBC) to be constructed for the NE - STEP demonstration system (demo) with the lowest risk possible. A systems engineering approach is recommended to ensure adequate requirements gathering, documentation, and mode ling that supports technology development relevant to advanced reactors while supporting crosscut interests in potential applications. A holistic systems engineering model was designed for the ART Energy Conversion program by leveraging Concurrent Engineering, Balance Model, Simplified V Model, and Project Management principles. The resulting model supports the identification and validation of lifecycle Brayton systems requirements, and allows designers to detail system-specific components relevant to the current stage in the lifecycle, while maintaining a holistic view of all system elements.

  3. Engineering Abstractions in Model Checking and Testing

    DEFF Research Database (Denmark)

    Achenbach, Michael; Ostermann, Klaus

    2009-01-01

    Abstractions are used in model checking to tackle problems like state space explosion or modeling of IO. The application of these abstractions in real software development processes, however, lacks engineering support. This is one reason why model checking is not widely used in practice yet...... and testing is still state of the art in falsification. We show how user-defined abstractions can be integrated into a Java PathFinder setting with tools like AspectJ or Javassist and discuss implications of remaining weaknesses of these tools. We believe that a principled engineering approach to designing...

  4. Mathematical modeling a chemical engineer's perspective

    CERN Document Server

    Rutherford, Aris

    1999-01-01

    Mathematical modeling is the art and craft of building a system of equations that is both sufficiently complex to do justice to physical reality and sufficiently simple to give real insight into the situation. Mathematical Modeling: A Chemical Engineer's Perspective provides an elementary introduction to the craft by one of the century's most distinguished practitioners.Though the book is written from a chemical engineering viewpoint, the principles and pitfalls are common to all mathematical modeling of physical systems. Seventeen of the author's frequently cited papers are reprinted to illus

  5. An Integrated Knowledge Based Engineering Mechatronics Modeling Approach to Support the Design of Unstable and Unmanned Aircraft

    NARCIS (Netherlands)

    Tian, F.N.

    2015-01-01

    The commercial transport aircraft industry is currently developing new “more electric aircraft” (MEA) designs in which various conventional mechanical, hydraulic and pneumatic power systems are replaced with electrically-based power systems. Their objective is to improve the overall flight

  6. Engineering model for impact of blunt projectiles on metallic sheets

    NARCIS (Netherlands)

    Roebroeks, G.; Carton, E.P.

    2014-01-01

    At TNO mind sized engineering models are created for specific penetration conditions. The models are energy based and calculate the energy absorbed by target deformation (strain energy) and displacement (kinetic energy). The input parameters are restricted to basic target material properties

  7. Systems metabolic engineering: genome-scale models and beyond.

    Science.gov (United States)

    Blazeck, John; Alper, Hal

    2010-07-01

    The advent of high throughput genome-scale bioinformatics has led to an exponential increase in available cellular system data. Systems metabolic engineering attempts to use data-driven approaches--based on the data collected with high throughput technologies--to identify gene targets and optimize phenotypical properties on a systems level. Current systems metabolic engineering tools are limited for predicting and defining complex phenotypes such as chemical tolerances and other global, multigenic traits. The most pragmatic systems-based tool for metabolic engineering to arise is the in silico genome-scale metabolic reconstruction. This tool has seen wide adoption for modeling cell growth and predicting beneficial gene knockouts, and we examine here how this approach can be expanded for novel organisms. This review will highlight advances of the systems metabolic engineering approach with a focus on de novo development and use of genome-scale metabolic reconstructions for metabolic engineering applications. We will then discuss the challenges and prospects for this emerging field to enable model-based metabolic engineering. Specifically, we argue that current state-of-the-art systems metabolic engineering techniques represent a viable first step for improving product yield that still must be followed by combinatorial techniques or random strain mutagenesis to achieve optimal cellular systems.

  8. Sensor Based Engine Life Calculation: A Probabilistic Perspective

    Science.gov (United States)

    Guo, Ten-Huei; Chen, Philip

    2003-01-01

    It is generally known that an engine component will accumulate damage (life usage) during its lifetime of use in a harsh operating environment. The commonly used cycle count for engine component usage monitoring has an inherent range of uncertainty which can be overly costly or potentially less safe from an operational standpoint. With the advance of computer technology, engine operation modeling, and the understanding of damage accumulation physics, it is possible (and desirable) to use the available sensor information to make a more accurate assessment of engine component usage. This paper describes a probabilistic approach to quantify the effects of engine operating parameter uncertainties on the thermomechanical fatigue (TMF) life of a selected engine part. A closed-loop engine simulation with a TMF life model is used to calculate the life consumption of different mission cycles. A Monte Carlo simulation approach is used to generate the statistical life usage profile for different operating assumptions. The probabilities of failure of different operating conditions are compared to illustrate the importance of the engine component life calculation using sensor information. The results of this study clearly show that a sensor-based life cycle calculation can greatly reduce the risk of component failure as well as extend on-wing component life by avoiding unnecessary maintenance actions.

  9. Reliability-Based Optimization in Structural Engineering

    DEFF Research Database (Denmark)

    Enevoldsen, I.; Sørensen, John Dalsgaard

    1994-01-01

    In this paper reliability-based optimization problems in structural engineering are formulated on the basis of the classical decision theory. Several formulations are presented: Reliability-based optimal design of structural systems with component or systems reliability constraints, reliability-b...

  10. An Integrated Knowledge Based Engineering Mechatronics Modeling Approach to Support the Design of Unstable and Unmanned Aircraft

    OpenAIRE

    Tian, F.N.

    2015-01-01

    The commercial transport aircraft industry is currently developing new “more electric aircraft” (MEA) designs in which various conventional mechanical, hydraulic and pneumatic power systems are replaced with electrically-based power systems. Their objective is to improve the overall flight performance by reducing the aircraft weight and by a lower overall energy requirement for the systems. The vision for the future is to ultimately replace all systems with electrical systems and even to repl...

  11. Spent fuel reprocessing system security engineering capability maturity model

    International Nuclear Information System (INIS)

    Liu Yachun; Zou Shuliang; Yang Xiaohua; Ouyang Zigen; Dai Jianyong

    2011-01-01

    In the field of nuclear safety, traditional work places extra emphasis on risk assessment related to technical skills, production operations, accident consequences through deterministic or probabilistic analysis, and on the basis of which risk management and control are implemented. However, high quality of product does not necessarily mean good safety quality, which implies a predictable degree of uniformity and dependability suited to the specific security needs. In this paper, we make use of the system security engineering - capability maturity model (SSE-CMM) in the field of spent fuel reprocessing, establish a spent fuel reprocessing systems security engineering capability maturity model (SFR-SSE-CMM). The base practices in the model are collected from the materials of the practice of the nuclear safety engineering, which represent the best security implementation activities, reflect the regular and basic work of the implementation of the security engineering in the spent fuel reprocessing plant, the general practices reveal the management, measurement and institutional characteristics of all process activities. The basic principles that should be followed in the course of implementation of safety engineering activities are indicated from 'what' and 'how' aspects. The model provides a standardized framework and evaluation system for the safety engineering of the spent fuel reprocessing system. As a supplement to traditional methods, this new assessment technique with property of repeatability and predictability with respect to cost, procedure and quality control, can make or improve the activities of security engineering to become a serial of mature, measurable and standard activities. (author)

  12. Mathematical Model of the Jet Engine Fuel System

    Directory of Open Access Journals (Sweden)

    Klimko Marek

    2015-01-01

    Full Text Available The paper discusses the design of a simplified mathematical model of the jet (turbo-compressor engine fuel system. The solution will be based on the regulation law, where the control parameter is a fuel mass flow rate and the regulated parameter is the rotational speed. A differential equation of the jet engine and also differential equations of other fuel system components (fuel pump, throttle valve, pressure regulator will be described, with respect to advanced predetermined simplifications.

  13. Mathematical Model of the Jet Engine Fuel System

    OpenAIRE

    Klimko Marek

    2015-01-01

    The paper discusses the design of a simplified mathematical model of the jet (turbo-compressor) engine fuel system. The solution will be based on the regulation law, where the control parameter is a fuel mass flow rate and the regulated parameter is the rotational speed. A differential equation of the jet engine and also differential equations of other fuel system components (fuel pump, throttle valve, pressure regulator) will be described, with respect to advanced predetermined simplifications.

  14. Mathematical Model of the Jet Engine Fuel System

    Science.gov (United States)

    Klimko, Marek

    2015-05-01

    The paper discusses the design of a simplified mathematical model of the jet (turbo-compressor) engine fuel system. The solution will be based on the regulation law, where the control parameter is a fuel mass flow rate and the regulated parameter is the rotational speed. A differential equation of the jet engine and also differential equations of other fuel system components (fuel pump, throttle valve, pressure regulator) will be described, with respect to advanced predetermined simplifications.

  15. Software Engineering Tools for Scientific Models

    Science.gov (United States)

    Abrams, Marc; Saboo, Pallabi; Sonsini, Mike

    2013-01-01

    Software tools were constructed to address issues the NASA Fortran development community faces, and they were tested on real models currently in use at NASA. These proof-of-concept tools address the High-End Computing Program and the Modeling, Analysis, and Prediction Program. Two examples are the NASA Goddard Earth Observing System Model, Version 5 (GEOS-5) atmospheric model in Cell Fortran on the Cell Broadband Engine, and the Goddard Institute for Space Studies (GISS) coupled atmosphere- ocean model called ModelE, written in fixed format Fortran.

  16. Software engineering with process algebra: Modelling client / server architecures

    NARCIS (Netherlands)

    Diertens, B.

    2009-01-01

    In previous work we described how the process algebra based language PSF can be used in software engineering, using the ToolBus, a coordination architecture also based on process algebra, as implementation model. We also described this software development process more formally by presenting the

  17. Vibrational Based Inspection of Civil Engineering Structures

    DEFF Research Database (Denmark)

    Rytter, Anders

    and Structural Engineering at the University of Aalborg since the beginning of 1992. Both projects have been supported by the Danish Technical Research Council. Further, the first mentioned project was supported by the Danish Energy Agency. Their financial support is gratefully acknowledged.......The thesis has been written in relation to two different research projects. Firstly, an offshore test programme, Integrated Experimental/Numerical Analysis of the Dynamic behavior of offshore structures, which was performed at the department of Building Technology and Structural Engineering...... at the University of Aalborg from 1988 to 1991. Secondly, a research project, In-Field Vibration Based Inspection of Civil Engineering Structures, which has been performed as a pilot project by the Consulting Engineers Rambøll, Hannemann and Højlund in cooperation with the department of Building Technology...

  18. Activity-based DEVS modeling

    DEFF Research Database (Denmark)

    Alshareef, Abdurrahman; Sarjoughian, Hessam S.; Zarrin, Bahram

    2018-01-01

    architecture and the UML concepts. In this paper, we further this work by grounding Activity-based DEVS modeling and developing a fully-fledged modeling engine to demonstrate applicability. We also detail the relevant aspects of the created metamodel in terms of modeling and simulation. A significant number...

  19. Engineering models and methods for industrial cell control

    DEFF Research Database (Denmark)

    Lynggaard, Hans Jørgen Birk; Alting, Leo

    1997-01-01

    This paper is concerned with the engineering, i.e. the designing and making, of industrial cell control systems. The focus is on automated robot welding cells in the shipbuilding industry. The industrial research project defines models and methods for design and implemen-tation of computer based....... Further, an engineering methodology is defined. The three elements enablers, architecture and methodology constitutes the Cell Control Engineering concept which has been defined and evaluated through the implementation of two cell control systems for robot welding cells in production at ODENSE STEEL...

  20. Engineering uses of physics-based ground motion simulations

    Science.gov (United States)

    Baker, Jack W.; Luco, Nicolas; Abrahamson, Norman A.; Graves, Robert W.; Maechling, Phillip J.; Olsen, Kim B.

    2014-01-01

    This paper summarizes validation methodologies focused on enabling ground motion simulations to be used with confidence in engineering applications such as seismic hazard analysis and dynmaic analysis of structural and geotechnical systems. Numberical simullation of ground motion from large erthquakes, utilizing physics-based models of earthquake rupture and wave propagation, is an area of active research in the earth science community. Refinement and validatoin of these models require collaboration between earthquake scientists and engineering users, and testing/rating methodolgies for simulated ground motions to be used with confidence in engineering applications. This paper provides an introduction to this field and an overview of current research activities being coordinated by the Souther California Earthquake Center (SCEC). These activities are related both to advancing the science and computational infrastructure needed to produce ground motion simulations, as well as to engineering validation procedures. Current research areas and anticipated future achievements are also discussed.

  1. Cloud-based Virtual Organization Engineering

    Directory of Open Access Journals (Sweden)

    Liviu Gabriel CRETU

    2012-01-01

    Full Text Available Nowadays we may notice that SOA arrived to its maturity stage and Cloud Computing brings the next paradigm-shift regarding the software delivery business model. In such a context, we consider that there is a need for frameworks to guide the creation, execution and management of virtual organizations (VO based on services from different Clouds. This paper will introduce the main components of such a framework that will innovatively combine the principles of event-driven SOA, REST and ISO/IEC 42010:2007 multiple views and viewpoints in order to provide the required methodology for Cloud-based virtual organization (Cloud-VO engi-neering. The framework will consider the resource concept found in software architectures like REST or RDF as the basic building block of Cloud-VO. and will make use of resources’ URIs to create the Cloud-VO’s resource allocation matrix. While the matrix is used to declare activity-resources relationships, the resource catalogue concept will be introduced as a way to describe the resource in one place, using as many viewpoints as needed, and then to reuse that description for the creation or simulation of different VOs.

  2. A theoretical model of biochemical control engineering based on the relation between oestrogens/progestagens and prostaglandins.

    Science.gov (United States)

    van der Veen, P H E

    2015-06-01

    A biological complex organism is involuntarily guided from all sides by measure and regulation systems. The human being is such a complex organism. Many cyclical processes are simultaneously at work, making it unclear how and why which process takes place at which moment. Noticeable examples are the 28-day menstrual cycle and the 40-week pregnancy. The time of activation in the middle of the menstrual is fairly clear. Hormonal changes also occur in this period. Why the hormonal changes occur, and what their relationship is with the activation of the processes is unclear. That is also the case during pregnancies. What is it that determines that a pregnancy should last an average of 40 weeks? What causes the changes in a complicated pregnancy? What are those changes? Prostaglandin concentrations have been found to have some relationship with these changes, but the activation of these changes and how to examine them is unknown. Using an example from practical experience, this article illustrates what Horrobin and Manku already reported in 1977, namely, the properties of prostaglandin E1 and 6-keto pgF1α: reversal effect with elevated concentration. The properties described is exceptionally suitable for the time of activation in a biochemically regulated measure and regulation system. These properties can help explain the occurrence of physiological cycles. The known electronic saw-tooth wave has a biochemical analogue with this. This paper describes the presumed relationship between hormones and the accompanying prostaglandins with the hormone effects based on what is known regarding their concentrations progress. This relationship reveals the practical consequences of the experimentally found sensitivity of biochemical effects with regard to the accompanying prostaglandins. This paper shows how the theoretical relationship between effects of oestrogens and progestagens result in a curve that comprise observable aspects of the Basal Body Temperature Curve. The

  3. Space shuttle main engine vibration data base

    Science.gov (United States)

    Lewallen, Pat

    1986-01-01

    The Space Shuttle Main Engine Vibration Data Base is described. Included is a detailed description of the data base components, the data acquisition process, the more sophisticated software routines, and the future data acquisition methods. Several figures and plots are provided to illustrate the various output formats accessible to the user. The numerous vibration data recall and analysis capabilities available through automated data base techniques are revealed.

  4. Project based learning for reactor engineering education

    International Nuclear Information System (INIS)

    Narabayashi, Tadashi; Tsuji, Masashi; Shimazu, Yoichiro

    2009-01-01

    Trial in education of nuclear engineering in Hokkaido University has proved to be quite attractive for students. It is an education system called Project Based Learning (PBL), which is not based on education by lecture only but based mostly on practice of students in the classroom. The system was adopted four years ago. In the actual class, we separated the student into several groups of the size about 6 students. In the beginning of each class room time, a brief explanations of the related theory or technical bases. Then the students discuss in their own group how to precede their design calculations and do the required calculation and evaluation. The target reactor type of each group was selected by the group members for themselves at the beginning of the semester as the first step of the project. The reactor types range from a small in house type to that for a nuclear ship. At the end of the semester, each group presents the final design. The presentation experience gives students a kind of fresh sensation. Nowadays the evaluation results of the subject by the students rank in the highest in the faculty of engineering. Based on the considerations above, we designed the framework of our PBL for reactor engineering. In this paper, we will present some lessons learned in this PBL education system from the educational points of view. The PBL education program is supported by IAE/METI in Japan for Nuclear Engineering Education. (author)

  5. Numerical modeling in materials science and engineering

    CERN Document Server

    Rappaz, Michel; Deville, Michel

    2003-01-01

    This book introduces the concepts and methodologies related to the modelling of the complex phenomena occurring in materials processing. After a short reminder of conservation laws and constitutive relationships, the authors introduce the main numerical methods: finite differences, finite volumes and finite elements. These techniques are developed in three main chapters of the book that tackle more specific problems: phase transformation, solid mechanics and fluid flow. The two last chapters treat inverse methods to obtain the boundary conditions or the material properties and stochastic methods for microstructural simulation. This book is intended for undergraduate and graduate students in materials science and engineering, mechanical engineering and physics and for engineering professionals or researchers who want to get acquainted with numerical simulation to model and compute materials processing.

  6. Engineering models and methods for industrial cell control

    DEFF Research Database (Denmark)

    Lynggaard, Hans Jørgen Birk; Alting, Leo

    1997-01-01

    This paper is concerned with the engineering, i.e. the designing and making, of industrial cell control systems. The focus is on automated robot welding cells in the shipbuilding industry. The industrial research project defines models and methods for design and implemen-tation of computer based...... control and monitor-ing systems for production cells. The project participants are The Danish Academy of Technical Sciences, the Institute of Manufacturing Engineering at the Technical University of Denmark and ODENSE STEEL SHIPYARD Ltd.The manufacturing environment and the current practice...... for engineering of cell control systems has been analysed as well as automation software enablers. A number of problems related to these issues are identified.In order to support engineering of cell control systems by the use of enablers, a generic cell control data model and an architecture has been defined...

  7. Space engineering modeling and optimization with case studies

    CERN Document Server

    Pintér, János

    2016-01-01

    This book presents a selection of advanced case studies that cover a substantial range of issues and real-world challenges and applications in space engineering. Vital mathematical modeling, optimization methodologies and numerical solution aspects of each application case study are presented in detail, with discussions of a range of advanced model development and solution techniques and tools. Space engineering challenges are discussed in the following contexts: •Advanced Space Vehicle Design •Computation of Optimal Low Thrust Transfers •Indirect Optimization of Spacecraft Trajectories •Resource-Constrained Scheduling, •Packing Problems in Space •Design of Complex Interplanetary Trajectories •Satellite Constellation Image Acquisition •Re-entry Test Vehicle Configuration Selection •Collision Risk Assessment on Perturbed Orbits •Optimal Robust Design of Hybrid Rocket Engines •Nonlinear Regression Analysis in Space Engineering< •Regression-Based Sensitivity Analysis and Robust Design ...

  8. Computer-assisted engineering data base

    Science.gov (United States)

    Dube, R. P.; Johnson, H. R.

    1983-01-01

    General capabilities of data base management technology are described. Information requirements posed by the space station life cycle are discussed, and it is asserted that data base management technology supporting engineering/manufacturing in a heterogeneous hardware/data base management system environment should be applied to meeting these requirements. Today's commercial systems do not satisfy all of these requirements. The features of an R&D data base management system being developed to investigate data base management in the engineering/manufacturing environment are discussed. Features of this system represent only a partial solution to space station requirements. Areas where this system should be extended to meet full space station information management requirements are discussed.

  9. Problem Based Learning in Engineering Education

    DEFF Research Database (Denmark)

    Dahms, Mona-Lisa; Sauerbier, Gabriele; Stubbe, Korinna

    2006-01-01

    This paper describes a recent EU-project from five European Institutions. The aim was the development and implementation of a new international Master’s programme for staff development, directed towards the introduction of Problem Based Learning methods in the field of engineering education...

  10. Qualitative models for space system engineering

    Science.gov (United States)

    Forbus, Kenneth D.

    1990-01-01

    The objectives of this project were: (1) to investigate the implications of qualitative modeling techniques for problems arising in the monitoring, diagnosis, and design of Space Station subsystems and procedures; (2) to identify the issues involved in using qualitative models to enhance and automate engineering functions. These issues include representing operational criteria, fault models, alternate ontologies, and modeling continuous signals at a functional level of description; and (3) to develop a prototype collection of qualitative models for fluid and thermal systems commonly found in Space Station subsystems. Potential applications of qualitative modeling to space-systems engineering, including the notion of intelligent computer-aided engineering are summarized. Emphasis is given to determining which systems of the proposed Space Station provide the most leverage for study, given the current state of the art. Progress on using qualitative models, including development of the molecular collection ontology for reasoning about fluids, the interaction of qualitative and quantitative knowledge in analyzing thermodynamic cycles, and an experiment on building a natural language interface to qualitative reasoning is reported. Finally, some recommendations are made for future research.

  11. 76 FR 54373 - Airworthiness Directives; Austro Engine GmbH Model E4 Diesel Piston Engines

    Science.gov (United States)

    2011-09-01

    ... Airworthiness Directives; Austro Engine GmbH Model E4 Diesel Piston Engines AGENCY: Federal Aviation..., contact Austro Engine GmbH, Rudolf-Diesel-Strasse 11, A-2700 Weiner Neustadt, Austria, phone: +43 2622... information, we estimate that this AD will affect about 32 model E4 diesel piston engines, installed on...

  12. 75 FR 68179 - Airworthiness Directives; Austro Engine GmbH Model E4 Diesel Piston Engines

    Science.gov (United States)

    2010-11-05

    ... Airworthiness Directives; Austro Engine GmbH Model E4 Diesel Piston Engines AGENCY: Federal Aviation.... Affected ADs (b) None. Applicability (c) This AD applies to Austro Engine GmbH model E4 diesel piston.... Contact Austro Engine GmbH, Rudolf-Diesel- Strasse 11, A-2700 Weiner Neustadt, Austria, telephone: +43...

  13. Quasi-1 Dimensional Modeling of Rotational Detonation Engines

    Data.gov (United States)

    National Aeronautics and Space Administration — This project looks to investigate the modeling of rotational detonation engines (RDE). RDEs are an alternative engine cycle to conventional liquid rocket engines,...

  14. Basis and tests for a service life model of cement based engineering Barrier materials of the low and medium radioactive waste Repository of El Cabril-Cordoba-Spain

    International Nuclear Information System (INIS)

    Andrade, C.; Castellote, M.; Zuloaga, P.; Navarro, M.; Ordofiez, M.

    2004-01-01

    The main cement based materials used as engineer barrier in the repository of El Cabril for low and medium radioactive wastes are the Cells, the Containers and the mortar filling the gaps between the drums introduced in the containers. Cells and containers are made of the same concrete composition while the mortar was specifically designed to be pump able and with high impermeability. The repository has a design life of 300-500 years and therefore, these structures should remain until this target service life. The possible aggressions that the cement based materials can suffer have been identified to be: carbonation, water permeation (leaching) and reinforcement corrosion. More unlikely might be the bio-attack. Chlorides are not in the environment but they are inside the drums as part of analytical wastes. In order to resist for the target period the concrete and mortar have been properly designed. The cement used is of low alkali content to avoid alkali-aggregate reaction and in spite there are not significant amount of sulphates in the groundwaters the cement is of low C3A content. The resulting concrete has a characteristic strength higher than 50 Mpa. Tests of mercury porosimetry, water absorption, oxygen and air permeability. carbonation depths, chloride diffusion coefficients and reinforcement corrosion rate. are currently carried out in order to control the actual production of containers and to monitor the aging of the existing structures. A service life model is being developed taking into account several scenarios with different concentrations of aggressive substances. A preliminary version of this service life model RSS presented in the paper. In conclusion: the establishment of a suitable model of service life of CBM used in repositories of radioactive wastes has the main difficulty of the lack of proper calibration of existing models and their use for much shorter service lives. In addition, there are still important items to be measured and collected

  15. Mechanics, Models and Methods in Civil Engineering

    CERN Document Server

    Maceri, Franco

    2012-01-01

    „Mechanics, Models and Methods in Civil Engineering” collects leading papers dealing with actual Civil Engineering problems. The approach is in the line of the Italian-French school and therefore deeply couples mechanics and mathematics creating new predictive theories, enhancing clarity in understanding, and improving effectiveness in applications. The authors of the contributions collected here belong to the Lagrange Laboratory, an European Research Network active since many years. This book will be of a major interest for the reader aware of modern Civil Engineering.

  16. Experiment-Based Teaching in Advanced Control Engineering

    Science.gov (United States)

    Precup, R.-E.; Preitl, S.; Radac, M.-B.; Petriu, E. M.; Dragos, C.-A.; Tar, J. K.

    2011-01-01

    This paper discusses an experiment-based approach to teaching an advanced control engineering syllabus involving controlled plant analysis and modeling, control structures and algorithms, real-time laboratory experiments, and their assessment. These experiments are structured around the representative case of the longitudinal slip control of an…

  17. Complete modeling for systems of a marine diesel engine

    Science.gov (United States)

    Nahim, Hassan Moussa; Younes, Rafic; Nohra, Chadi; Ouladsine, Mustapha

    2015-03-01

    This paper presents a simulator model of a marine diesel engine based on physical, semi-physical, mathematical and thermodynamic equations, which allows fast predictive simulations. The whole engine system is divided into several functional blocks: cooling, lubrication, air, injection, combustion and emissions. The sub-models and dynamic characteristics of individual blocks are established according to engine working principles equations and experimental data collected from a marine diesel engine test bench for SIMB Company under the reference 6M26SRP1. The overall engine system dynamics is expressed as a set of simultaneous algebraic and differential equations using sub-blocks and S-Functions of Matlab/Simulink. The simulation of this model, implemented on Matlab/Simulink has been validated and can be used to obtain engine performance, pressure, temperature, efficiency, heat release, crank angle, fuel rate, emissions at different sub-blocks. The simulator will be used, in future work, to study the engine performance in faulty conditions, and can be used to assist marine engineers in fault diagnosis and estimation (FDI) as well as designers to predict the behavior of the cooling system, lubrication system, injection system, combustion, emissions, in order to optimize the dimensions of different components. This program is a platform for fault simulator, to investigate the impact on sub-blocks engine's output of changing values for faults parameters such as: faulty fuel injector, leaky cylinder, worn fuel pump, broken piston rings, a dirty turbocharger, dirty air filter, dirty air cooler, air leakage, water leakage, oil leakage and contamination, fouling of heat exchanger, pumps wear, failure of injectors (and many others).

  18. Reliability modeling of an engineered barrier system

    International Nuclear Information System (INIS)

    Ananda, M.M.A.; Singh, A.K.; Flueck, J.A.

    1993-01-01

    The Weibull distribution is widely used in reliability literature as a distribution of time to failure, as it allows for both increasing failure rate (IFR) and decreasing failure rate (DFR) models. It has also been used to develop models for an engineered barrier system (EBS), which is known to be one of the key components in a deep geological repository for high level radioactive waste (HLW). The EBS failure time can more realistically be modelled by an IFR distribution, since the failure rate for the EBS is not expected to decrease with time. In this paper, we use an IFR distribution to develop a reliability model for the EBS

  19. Mean Value Modelling of a Turbocharged SI Engine

    DEFF Research Database (Denmark)

    Müller, Martin; Hendricks, Elbert; Sorenson, Spencer C.

    1998-01-01

    but not the cycle-by-cycle behavior. In principle such models are also physically based,are very compact in a mathematical sense but nevertheless can have reasonable prediction accuracy. Presently no MVEMs have been constructed for intercooled turbocharged SI engines because their complexity confounds the simple...... reasonable accuracy for realistic operating scenarios....

  20. Concurrent engineering and product models in seafood companies

    DEFF Research Database (Denmark)

    Jonsdottir, Stella; Vesterager, Johan; Børresen, Torger

    1998-01-01

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

  1. Efficient Proof Engines for Bounded Model Checking of Hybrid Systems

    DEFF Research Database (Denmark)

    Fränzle, Martin; Herde, Christian

    2005-01-01

    In this paper we present HySat, a new bounded model checker for linear hybrid systems, incorporating a tight integration of a DPLL-based pseudo-Boolean SAT solver and a linear programming routine as core engine. In contrast to related tools like MathSAT, ICS, or CVC, our tool exploits all...

  2. Human factors engineering program review model

    International Nuclear Information System (INIS)

    1994-07-01

    The staff of the Nuclear Regulatory Commission is performing nuclear power plant design certification reviews based on a design process plan that describes the human factors engineering (HFE) program elements that are necessary and sufficient to develop an acceptable detailed design specification and an acceptable implemented design. There are two principal reasons for this approach. First, the initial design certification applications submitted for staff review did not include detailed design information. Second, since human performance literature and industry experiences have shown that many significant human factors issues arise early in the design process, review of the design process activities and results is important to the evaluation of an overall design. However, current regulations and guidance documents do not address the criteria for design process review. Therefore, the HFE Program Review Model (HFE PRM) was developed as a basis for performing design certification reviews that include design process evaluations as well as review of the final design. A central tenet of the HFE PRM is that the HFE aspects of the plant should be developed, designed, and evaluated on the basis of a structured top-down system analysis using accepted HFE principles. The HFE PRM consists of ten component elements. Each element in divided into four sections: Background, Objective, Applicant Submittals, and Review Criteria. This report describes the development of the HFE PRM and gives a detailed description of each HFE review element

  3. Human factors engineering program review model

    Energy Technology Data Exchange (ETDEWEB)

    1994-07-01

    The staff of the Nuclear Regulatory Commission is performing nuclear power plant design certification reviews based on a design process plan that describes the human factors engineering (HFE) program elements that are necessary and sufficient to develop an acceptable detailed design specification and an acceptable implemented design. There are two principal reasons for this approach. First, the initial design certification applications submitted for staff review did not include detailed design information. Second, since human performance literature and industry experiences have shown that many significant human factors issues arise early in the design process, review of the design process activities and results is important to the evaluation of an overall design. However, current regulations and guidance documents do not address the criteria for design process review. Therefore, the HFE Program Review Model (HFE PRM) was developed as a basis for performing design certification reviews that include design process evaluations as well as review of the final design. A central tenet of the HFE PRM is that the HFE aspects of the plant should be developed, designed, and evaluated on the basis of a structured top-down system analysis using accepted HFE principles. The HFE PRM consists of ten component elements. Each element in divided into four sections: Background, Objective, Applicant Submittals, and Review Criteria. This report describes the development of the HFE PRM and gives a detailed description of each HFE review element.

  4. Mathematical modeling and computational intelligence in engineering applications

    CERN Document Server

    Silva Neto, Antônio José da; Silva, Geraldo Nunes

    2016-01-01

    This book brings together a rich selection of studies in mathematical modeling and computational intelligence, with application in several fields of engineering, like automation, biomedical, chemical, civil, electrical, electronic, geophysical and mechanical engineering, on a multidisciplinary approach. Authors from five countries and 16 different research centers contribute with their expertise in both the fundamentals and real problems applications based upon their strong background on modeling and computational intelligence. The reader will find a wide variety of applications, mathematical and computational tools and original results, all presented with rigorous mathematical procedures. This work is intended for use in graduate courses of engineering, applied mathematics and applied computation where tools as mathematical and computational modeling, numerical methods and computational intelligence are applied to the solution of real problems.

  5. Model Based Definition

    Science.gov (United States)

    Rowe, Sidney E.

    2010-01-01

    In September 2007, the Engineering Directorate at the Marshall Space Flight Center (MSFC) created the Design System Focus Team (DSFT). MSFC was responsible for the in-house design and development of the Ares 1 Upper Stage and the Engineering Directorate was preparing to deploy a new electronic Configuration Management and Data Management System with the Design Data Management System (DDMS) based upon a Commercial Off The Shelf (COTS) Product Data Management (PDM) System. The DSFT was to establish standardized CAD practices and a new data life cycle for design data. Of special interest here, the design teams were to implement Model Based Definition (MBD) in support of the Upper Stage manufacturing contract. It is noted that this MBD does use partially dimensioned drawings for auxiliary information to the model. The design data lifecycle implemented several new release states to be used prior to formal release that allowed the models to move through a flow of progressive maturity. The DSFT identified some 17 Lessons Learned as outcomes of the standards development, pathfinder deployments and initial application to the Upper Stage design completion. Some of the high value examples are reviewed.

  6. On science versus engineering in hydrological modelling

    Science.gov (United States)

    Melsen, Lieke

    2017-04-01

    It is always stressed that hydrological modelling is very important, to prevent floods, to mitigate droughts, to ensure food production or nature conservation. All very true, but I believe that focussing so much on the application of our knowledge (which I call `the engineering approach'), does not stimulate thorough system understanding (which I call `the scientific approach'). In many studies, science and engineering approaches are mixed, which results in large uncertainty e.g. due to a lack of system understanding. To what extent engineering and science approached are mixed depends on the Philosophy of Science of the researcher; verificationism seems to be closer related to engineering, than falsificationism or Bayesianism. In order to grow our scientific knowledge, which means increasing our understanding of the system, we need to be more critical towards the models that we use, but also recognize all the processes that influence the hydrological cycle. In an era called 'The Anthropocene' the influence of humans on the water system can no longer be neglected, and if we choose a scientific approach we have to account for human-induced processes. Summarizing, I believe that we have to account for human impact on the hydrological system, but we have to resist the temptation to directly quantify the hydrological impact on the human system.

  7. A control engineering model of calcium regulation.

    Science.gov (United States)

    Christie, Christopher R; Achenie, Luke E K; Ogunnaike, Babatunde A

    2014-08-01

    A control engineering perspective provides a framework for representing important mechanistic details of the calcium (Ca) regulatory system efficiently. The resulting model facilitates the testing of hypotheses about mechanisms underlying the emergence of known Ca-related pathologies. The objective of this work is to develop a comprehensive computational model that will enable quantitative understanding of plasma Ca regulation under normal and pathological conditions. Ca regulation is represented as an engineering control system where physiological subprocesses are mapped onto corresponding block components (sensor, controller, actuator, and process), and underlying mechanisms are represented by differential equations. The resulting model is validated with clinical observations of induced hypo- or hypercalcemia in healthy subjects, and its applicability is demonstrated by comparing model predictions of Ca-related pathologies to corresponding clinical data. Our model accurately predicts clinical responses to induced hypo- and hypercalcemia in healthy subjects within a framework that facilitates the representation of Ca-related pathologies in terms of control system component defects. The model also enables a deeper understanding of the emergence of pathologies and the testing of hypotheses about related features of Ca regulation-for example, why primary hyperparathyroidism and hypoparathyroidism arise from "controller defects." The control engineering framework provides an efficient means of organizing the subprocesses constituting Ca regulation, thereby facilitating a fundamental understanding of this complex process. The resulting validated model's predictions are consistent with clinically observed short- and long-term dynamic characteristics of the Ca regulatory system in both healthy and diseased patients. The model also enables simulation of currently infeasible clinical tests and generates predictions of physiological variables that are currently not

  8. TOWARD SOFTWARE ENGINEERING PRINCIPLES BASED ON ISLAMIC ETHICAL VALUES

    Directory of Open Access Journals (Sweden)

    shihab A. Hameed

    2010-09-01

    Full Text Available Software is the core for Computer-based applications which became an essential part for critical control systems, health and human life guard systems, financial and banking systems, educational and other systems. It requires qualified software engineers professionally and ethically. L.R and survey results show that software engineering professionals facing several ethical related problems which are costly, harmful and affected high ratio of people. Professional organizations like ACM, IEEE, ABET and CSAC have established codes of ethics to help software engineering professionals to understand and manage their ethical responsibilities. Islam considers ethics an essential factor to build individuals,communities and society. Islamic Ethics are set of moral principles and guidance that recognizes what is right behavior from wrong, which are comprehensive, stable, fair, and historically prove success in building ethically great society. The 1.3 billions of Muslims with 10s of thousands of software engineers should have an effective role in software development and life, which requires them to understand and implement ethics, specially the Islamic ethics in their work. This paper is a frame-work for modeling software engineering principle. It focuses mainly on adopting a new version of software engineering principle based on Islamic ethical values.

  9. Estimation of some stochastic models used in reliability engineering

    International Nuclear Information System (INIS)

    Huovinen, T.

    1989-04-01

    The work aims to study the estimation of some stochastic models used in reliability engineering. In reliability engineering continuous probability distributions have been used as models for the lifetime of technical components. We consider here the following distributions: exponential, 2-mixture exponential, conditional exponential, Weibull, lognormal and gamma. Maximum likelihood method is used to estimate distributions from observed data which may be either complete or censored. We consider models based on homogeneous Poisson processes such as gamma-poisson and lognormal-poisson models for analysis of failure intensity. We study also a beta-binomial model for analysis of failure probability. The estimators of the parameters for three models are estimated by the matching moments method and in the case of gamma-poisson and beta-binomial models also by maximum likelihood method. A great deal of mathematical or statistical problems that arise in reliability engineering can be solved by utilizing point processes. Here we consider the statistical analysis of non-homogeneous Poisson processes to describe the failing phenomena of a set of components with a Weibull intensity function. We use the method of maximum likelihood to estimate the parameters of the Weibull model. A common cause failure can seriously reduce the reliability of a system. We consider a binomial failure rate (BFR) model as an application of the marked point processes for modelling common cause failure in a system. The parameters of the binomial failure rate model are estimated with the maximum likelihood method

  10. 76 FR 33660 - Airworthiness Directives; Austro Engine GmbH Model E4 Diesel Piston Engines

    Science.gov (United States)

    2011-06-09

    ... Model E4 Diesel Piston Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of... 2010-23-09, Amendment 39-16498 (75 FR 68179, November 5, 2010), for Austro Engine GmbH model E4 diesel... 2011-0039, dated March 8, 2011, adding a terminating action on Austro Engine GmbH model E4 diesel...

  11. Porous titanium bases for osteochondral tissue engineering

    Science.gov (United States)

    Nover, Adam B.; Lee, Stephanie L.; Georgescu, Maria S.; Howard, Daniel R.; Saunders, Reuben A.; Yu, William T.; Klein, Robert W.; Napolitano, Anthony P.; Ateshian, Gerard A.

    2015-01-01

    Tissue engineering of osteochondral grafts may offer a cell-based alternative to native allografts, which are in short supply. Previous studies promote the fabrication of grafts consisting of a viable cell-seeded hydrogel integrated atop a porous, bone-like metal. Advantages of the manufacturing process have led to the evaluation of porous titanium as the bone-like base material. Here, porous titanium was shown to support the growth of cartilage to produce native levels of Young’s modulus, using a clinically relevant cell source. Mechanical and biochemical properties were similar or higher for the osteochondral constructs compared to chondral-only controls. Further investigation into the mechanical influence of the base on the composite material suggests that underlying pores may decrease interstitial fluid pressurization and applied strains, which may be overcome by alterations to the base structure. Future studies aim to optimize titanium-based tissue engineered osteochondral constructs to best match the structural architecture and strength of native grafts. Statement of Significance The studies described in this manuscript follow up on previous studies from our lab pertaining to the fabrication of osteochondral grafts that consist of a bone-like porous metal and a chondrocyte-seeded hydrogel. Here, tissue engineered osteochondral grafts were cultured to native stiffness using adult chondrocytes, a clinically relevant cell source, and a porous titanium base, a material currently used in clinical implants. This porous titanium is manufactured via selective laser melting, offering the advantages of precise control over shape, pore size, and orientation. Additionally, this manuscript describes the mechanical influence of the porous base, which may have applicability to porous bases derived from other materials. PMID:26320541

  12. Defining a region of optimization based on engine usage data

    Science.gov (United States)

    Jiang, Li; Lee, Donghoon; Yilmaz, Hakan; Stefanopoulou, Anna

    2015-08-04

    Methods and systems for engine control optimization are provided. One or more operating conditions of a vehicle engine are detected. A value for each of a plurality of engine control parameters is determined based on the detected one or more operating conditions of the vehicle engine. A range of the most commonly detected operating conditions of the vehicle engine is identified and a region of optimization is defined based on the range of the most commonly detected operating conditions of the vehicle engine. The engine control optimization routine is initiated when the one or more operating conditions of the vehicle engine are within the defined region of optimization.

  13. Repository-based software engineering program

    Science.gov (United States)

    Wilson, James

    1992-01-01

    The activities performed during September 1992 in support of Tasks 01 and 02 of the Repository-Based Software Engineering Program are outlined. The recommendations and implementation strategy defined at the September 9-10 meeting of the Reuse Acquisition Action Team (RAAT) are attached along with the viewgraphs and reference information presented at the Institute for Defense Analyses brief on legal and patent issues related to software reuse.

  14. Comparison of drug and cell-based delivery: engineered adult mesenchymal stem cells expressing soluble tumor necrosis factor receptor II prevent arthritis in mouse and rat animal models.

    Science.gov (United States)

    Liu, Linda N; Wang, Gang; Hendricks, Kyle; Lee, Keunmyoung; Bohnlein, Ernst; Junker, Uwe; Mosca, Joseph D

    2013-05-01

    Rheumatoid arthritis (RA) is a systemic autoimmune disease with unknown etiology where tumor necrosis factor-α (TNFα) plays a critical role. Etanercept, a recombinant fusion protein of human soluble tumor necrosis factor receptor II (hsTNFR) linked to the Fc portion of human IgG1, is used to treat RA based on the rationale that sTNFR binds TNFα and blocks TNFα-mediated inflammation. We compared hsTNFR protein delivery from genetically engineered human mesenchymal stem cells (hMSCs) with etanercept. Blocking TNFα-dependent intercellular adhesion molecule-1 expression on transduced hMSCs and inhibition of nitric oxide production from TNFα-treated bovine chondrocytes by conditioned culture media from transduced hMSCs demonstrated the functionality of the hsTNFR construction. Implanted hsTNFR-transduced mesenchymal stem cells (MSCs) reduced mouse serum circulating TNFα generated from either implanted TNFα-expressing cells or lipopolysaccharide induction more effectively than etanercept (TNFα, 100%; interleukin [IL]-1α, 90%; and IL-6, 60% within 6 hours), suggesting faster clearance of the soluble tumor necrosis factor receptor (sTNFR)-TNFα complex from the animals. In vivo efficacy of sTNFR-transduced MSCs was illustrated in two (immune-deficient and immune-competent) arthritic rodent models. In the antibody-induced arthritis BalbC/SCID mouse model, intramuscular injection of hsTNFR-transduced hMSCs reduced joint inflammation by 90% compared with untransduced hMSCs; in the collagen-induced arthritis Fischer rat model, both sTNFR-transduced rat MSCs and etanercept inhibited joint inflammation by 30%. In vitro chondrogenesis assays showed the ability of TNFα and IL1α, but not interferon γ, to inhibit hMSC differentiation to chondrocytes, illustrating an additional negative role for inflammatory cytokines in joint repair. The data support the utility of hMSCs as therapeutic gene delivery vehicles and their potential to be used in alleviating inflammation

  15. Radiological Engineering: A graduate engineering - based curriculum for radiation protection

    International Nuclear Information System (INIS)

    Kearfott, K.J.; Wepfer, W.J.

    1994-01-01

    Several U.S. universities maintain formal graduate health physics curricula within their Colleges of Engineering. The term radiological engineering was coined to describe the discipline of applying engineering principles to the radiation protection aspects of nuclear technology. Radiological engineering programmes may require a specific core group of courses such as radiation biology, radiation protection practice, nuclear physics, radiation detectors, and radiation dosimetry. Students then might specialist in environmental, nuclear facilities or medical applications areas by selecting advanced courses and graduate design or research projects. In some instances the master's degree may be completed through remotely-delivered lectures. Such programmes promise to assist in educating a new group of engineering professionals dedicated to the safe utilisation of nuclear technology. The Georgis Institute of Technology's programme will serve as the specific example for this report. 8 refs., 1 fig

  16. Multifunctional Collaborative Modeling and Analysis Methods in Engineering Science

    Science.gov (United States)

    Ransom, Jonathan B.; Broduer, Steve (Technical Monitor)

    2001-01-01

    Engineers are challenged to produce better designs in less time and for less cost. Hence, to investigate novel and revolutionary design concepts, accurate, high-fidelity results must be assimilated rapidly into the design, analysis, and simulation process. This assimilation should consider diverse mathematical modeling and multi-discipline interactions necessitated by concepts exploiting advanced materials and structures. Integrated high-fidelity methods with diverse engineering applications provide the enabling technologies to assimilate these high-fidelity, multi-disciplinary results rapidly at an early stage in the design. These integrated methods must be multifunctional, collaborative, and applicable to the general field of engineering science and mechanics. Multifunctional methodologies and analysis procedures are formulated for interfacing diverse subdomain idealizations including multi-fidelity modeling methods and multi-discipline analysis methods. These methods, based on the method of weighted residuals, ensure accurate compatibility of primary and secondary variables across the subdomain interfaces. Methods are developed using diverse mathematical modeling (i.e., finite difference and finite element methods) and multi-fidelity modeling among the subdomains. Several benchmark scalar-field and vector-field problems in engineering science are presented with extensions to multidisciplinary problems. Results for all problems presented are in overall good agreement with the exact analytical solution or the reference numerical solution. Based on the results, the integrated modeling approach using the finite element method for multi-fidelity discretization among the subdomains is identified as most robust. The multiple-method approach is advantageous when interfacing diverse disciplines in which each of the method's strengths are utilized. The multifunctional methodology presented provides an effective mechanism by which domains with diverse idealizations are

  17. A Plastic Damage Mechanics Model for Engineered Cementitious Composites

    DEFF Research Database (Denmark)

    Dick-Nielsen, Lars; Stang, Henrik; Poulsen, Peter Noe

    2007-01-01

    This paper discusses the establishment of a plasticity-based damage mechanics model for Engineered Cementitious Composites (ECC). The present model differs from existing models by combining a matrix and fiber description in order to describe the behavior of the ECC material. The model provides in...... information about crack opening and spacing, which makes it possible to assess the condition of a structure in the serviceability state. A simulation of a four point bending beam is performed to demonstrate the capability of the model....

  18. Model Based Temporal Reasoning

    Science.gov (United States)

    Rabin, Marla J.; Spinrad, Paul R.; Fall, Thomas C.

    1988-03-01

    Systems that assess the real world must cope with evidence that is uncertain, ambiguous, and spread over time. Typically, the most important function of an assessment system is to identify when activities are occurring that are unusual or unanticipated. Model based temporal reasoning addresses both of these requirements. The differences among temporal reasoning schemes lies in the methods used to avoid computational intractability. If we had n pieces of data and we wanted to examine how they were related, the worst case would be where we had to examine every subset of these points to see if that subset satisfied the relations. This would be 2n, which is intractable. Models compress this; if several data points are all compatible with a model, then that model represents all those data points. Data points are then considered related if they lie within the same model or if they lie in models that are related. Models thus address the intractability problem. They also address the problem of determining unusual activities if the data do not agree with models that are indicated by earlier data then something out of the norm is taking place. The models can summarize what we know up to that time, so when they are not predicting correctly, either something unusual is happening or we need to revise our models. The model based reasoner developed at Advanced Decision Systems is thus both intuitive and powerful. It is currently being used on one operational system and several prototype systems. It has enough power to be used in domains spanning the spectrum from manufacturing engineering and project management to low-intensity conflict and strategic assessment.

  19. Simulation based engineering in fluid flow design

    CERN Document Server

    Rao, J S

    2017-01-01

    This volume offers a tool for High Performance Computing (HPC). A brief historical background on the subject is first given. Fluid Statics dealing with Pressure in fluids at rest, Buoyancy and Basics of Thermodynamics are next presented. The Finite Volume Method, the most convenient process for HPC, is explained in one-dimensional approach to diffusion with convection and pressure velocity coupling. Adiabatic, isentropic and supersonic flows in quasi-one dimensional flows in axisymmetric nozzles is considered before applying CFD solutions. Though the theory is restricted to one-dimensional cases, three-dimensional CFD examples are also given. Lastly, nozzle flows with normal shocks are presented using turbulence models. Worked examples and exercises are given in each chapter. Fluids transport thermal energy for its conversion to kinetic energy, thus playing a major role that is central to all heat engines. With the advent of rotating machinery in the 20th century, Fluid Engineering was developed in the form o...

  20. Distributed search engine architecture based on topic specific searches

    Science.gov (United States)

    Abudaqqa, Yousra; Patel, Ahmed

    2015-05-01

    Indisputably, search engines (SEs) abound. The monumental growth of users performing online searches on the Web is a contending issue in the contemporary world nowadays. For example, there are tens of billions of searches performed everyday, which typically offer the users many irrelevant results which are time consuming and costly to the user. Based on the afore-going problem it has become a herculean task for existing Web SEs to provide complete, relevant and up-to-date information response to users' search queries. To overcome this problem, we developed the Distributed Search Engine Architecture (DSEA), which is a new means of smart information query and retrieval of the World Wide Web (WWW). In DSEAs, multiple autonomous search engines, owned by different organizations or individuals, cooperate and act as a single search engine. This paper includes the work reported in this research focusing on development of DSEA, based on topic-specific specialised search engines. In DSEA, the results to specific queries could be provided by any of the participating search engines, for which the user is unaware of. The important design goal of using topic-specific search engines in the research is to build systems that can effectively be used by larger number of users simultaneously. Efficient and effective usage with good response is important, because it involves leveraging the vast amount of searched data from the World Wide Web, by categorising it into condensed focused topic -specific results that meet the user's queries. This design model and the development of the DSEA adopt a Service Directory (SD) to route queries towards topic-specific document hosting SEs. It displays the most acceptable performance which is consistent with the requirements of the users. The evaluation results of the model return a very high priority score which is associated with each frequency of a keyword.

  1. Software Engineering and Swarm-Based Systems

    Science.gov (United States)

    Hinchey, Michael G.; Sterritt, Roy; Pena, Joaquin; Rouff, Christopher A.

    2006-01-01

    We discuss two software engineering aspects in the development of complex swarm-based systems. NASA researchers have been investigating various possible concept missions that would greatly advance future space exploration capabilities. The concept mission that we have focused on exploits the principles of autonomic computing as well as being based on the use of intelligent swarms, whereby a (potentially large) number of similar spacecraft collaborate to achieve mission goals. The intent is that such systems not only can be sent to explore remote and harsh environments but also are endowed with greater degrees of protection and longevity to achieve mission goals.

  2. An engineering model for seismicity of India

    Directory of Open Access Journals (Sweden)

    S. Jayalakshmi

    2015-01-01

    Full Text Available This article explores an engineering approach to model the seismic activity in India. Finite element analysis is carried out to estimate the stresses and displacements in the Indian plate. Assuming the Himalayan boundary as fixed, the plate-driving forces are modelled as axial forces applied at the mid-oceanic ridge between the Indian and African plates. The effect of Aravali, Dharwar and Bundelkhand cratons on the stress patterns in the plate is also studied. The obtained results are validated to the extent possible with the available recorded seismicity data and measurements from Global Positioning System (GPS.

  3. Generomak: Fusion physics, engineering and costing model

    International Nuclear Information System (INIS)

    Delene, J.G.; Krakowski, R.A.; Sheffield, J.; Dory, R.A.

    1988-06-01

    A generic fusion physics, engineering and economics model (Generomak) was developed as a means of performing consistent analysis of the economic viability of alternative magnetic fusion reactors. The original Generomak model developed at Oak Ridge by Sheffield was expanded for the analyses of the Senior Committee on Environmental Safety and Economics of Magnetic Fusion Energy (ESECOM). This report describes the Generomak code as used by ESECOM. The input data used for each of the ten ESECOM fusion plants and the Generomak code output for each case is given. 14 refs., 3 figs., 17 tabs

  4. Finite element modeling for materials engineers using Matlab

    CERN Document Server

    Oluwole, Oluleke

    2014-01-01

    Finite Element Modeling for Materials Engineers Using MATLAB® combines the finite element method with MATLAB to offer materials engineers a fast and code-free way of modeling for many materials processes.

  5. Numerical modeling of hydrogen-fueled internal combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, N.L.; Amsden, A.A.

    1996-12-31

    The planned use of hydrogen as the energy carrier of the future introduces new challenges and opportunities, especially to the engine design community. Hydrogen is a bio-friendly fuel that can be produced from renewable resources and has no carbon dioxide combustion products; and in a properly designed ICE, almost zero NO{sub x} and hydrocarbon emissions can be achieved. Because of the unique properties of hydrogen combustion - in particular the highly wrinkled nature of the laminar flame front due to the preferential diffusion instability - modeling approaches for hydrocarbon gaseous fuels are not generally applicable to hydrogen combustion. This paper reports on the current progress to develop a engine design capability based on KIVA family of codes for hydrogen-fueled, spark-ignited engines in support of the National Hydrogen Program. A turbulent combustion model, based on a modified eddy-turnover model in conjunction with an intake flow valve model, is found to describe well the efficiency and NO{sub x} emissions of this engine satisfy the Equivalent Zero Emission Vehicle (EZEV) standard established by the California Resource Board. 26 refs., 10 figs., 1 tab.

  6. Simulation based engineering in solid mechanics

    CERN Document Server

    Rao, J S

    2017-01-01

    This book begins with a brief historical perspective of the advent of rotating machinery in 20th century Solid Mechanics and the development of the discipline of the Strength of Materials. High Performance Computing (HPC) and Simulation Based Engineering Science (SBES) have gradually replaced the conventional approach in Design bringing science directly into engineering without approximations. A recap of the required mathematical principles is given. The science of deformation, strain and stress at a point under the application of external traction loads is next presented. Only one-dimensional structures classified as Bars (axial loads), Rods (twisting loads) and Beams (bending loads) are considered in this book. The principal stresses and strains and von Mises stress and strain that used in design of structures are next presented. Lagrangian solution was used to derive the governing differential equations consistent with assumed deformation field and solution for deformations, strains and stresses were obtai...

  7. Problem-based teaching in engineering education

    Directory of Open Access Journals (Sweden)

    Kuimova Marina

    2016-01-01

    Full Text Available The aerospace industry requires highly educated, motivated engineers capable of working with increasingly complex processes and equipment, rapidly-changing requirements, and the need to constantly improve production efficiency. Colleges and universities throughout the world strive to provide training to young professionals for jobs in high-tech industries and to provide not only core technical knowledge, but also training on how to approach problems creatively and to generate novel solutions to problems. Problem-based learning (PBL contributes to solving this problem. This paper reviews the literature on PBL, studies its benefits and drawbacks, and presents the positive results achieved by its implementation in the training of engineering students at Tomsk Polytechnic University.

  8. Matrix models, geometric engineering and elliptic genera

    International Nuclear Information System (INIS)

    Hollowood, Timothy; Iqbal, Amer; Vafa, Cumrun

    2008-01-01

    We compute the prepotential of N = 2 supersymmetric gauge theories in four dimensions obtained by toroidal compactifications of gauge theories from 6 dimensions, as a function of Kaehler and complex moduli of T 2 . We use three different methods to obtain this: matrix models, geometric engineering and instanton calculus. Matrix model approach involves summing up planar diagrams of an associated gauge theory on T 2 . Geometric engineering involves considering F-theory on elliptic threefolds, and using topological vertex to sum up worldsheet instantons. Instanton calculus involves computation of elliptic genera of instanton moduli spaces on R 4 . We study the compactifications of N = 2* theory in detail and establish equivalence of all these three approaches in this case. As a byproduct we geometrically engineer theories with massive adjoint fields. As one application, we show that the moduli space of mass deformed M5-branes wrapped on T 2 combines the Kaehler and complex moduli of T 2 and the mass parameter into the period matrix of a genus 2 curve

  9. Practice-based systems engineering programme

    CSIR Research Space (South Africa)

    Goncalves, D

    2010-08-01

    Full Text Available South Africa, and indeed internationally, has been experiencing a shortage of systems engineers. On the other hand we seem to have only introductory systems engineering courses at local universities. Systems engineers have developed by means...

  10. Computational Fluid Dynamics Modeling of a Supersonic Nozzle and Integration into a Variable Cycle Engine Model

    Science.gov (United States)

    Connolly, Joseph W.; Friedlander, David; Kopasakis, George

    2015-01-01

    This paper covers the development of an integrated nonlinear dynamic simulation for a variable cycle turbofan engine and nozzle that can be integrated with an overall vehicle Aero-Propulso-Servo-Elastic (APSE) model. A previously developed variable cycle turbofan engine model is used for this study and is enhanced here to include variable guide vanes allowing for operation across the supersonic flight regime. The primary focus of this study is to improve the fidelity of the model's thrust response by replacing the simple choked flow equation convergent-divergent nozzle model with a MacCormack method based quasi-1D model. The dynamic response of the nozzle model using the MacCormack method is verified by comparing it against a model of the nozzle using the conservation element/solution element method. A methodology is also presented for the integration of the MacCormack nozzle model with the variable cycle engine.

  11. Post-Synapse Model Cell for Synaptic Glutamate Receptor (GluR-Based Biosensing: Strategy and Engineering to Maximize Ligand-Gated Ion-Flux Achieving High Signal-to-Noise Ratio

    Directory of Open Access Journals (Sweden)

    Tetsuya Haruyama

    2012-01-01

    Full Text Available Cell-based biosensing is a “smart” way to obtain efficacy-information on the effect of applied chemical on cellular biological cascade. We have proposed an engineered post-synapse model cell-based biosensors to investigate the effects of chemicals on ionotropic glutamate receptor (GluR, which is a focus of attention as a molecular target for clinical neural drug discovery. The engineered model cell has several advantages over native cells, including improved ease of handling and better reproducibility in the application of cell-based biosensors. However, in general, cell-based biosensors often have low signal-to-noise (S/N ratios due to the low level of cellular responses. In order to obtain a higher S/N ratio in model cells, we have attempted to design a tactic model cell with elevated cellular response. We have revealed that the increase GluR expression level is not directly connected to the amplification of cellular responses because the saturation of surface expression of GluR, leading to a limit on the total ion influx. Furthermore, coexpression of GluR with a voltage-gated potassium channel increased Ca2+ ion influx beyond levels obtained with saturating amounts of GluR alone. The construction of model cells based on strategy of amplifying ion flux per individual receptors can be used to perform smart cell-based biosensing with an improved S/N ratio.

  12. Post-synapse model cell for synaptic glutamate receptor (GluR)-based biosensing: strategy and engineering to maximize ligand-gated ion-flux achieving high signal-to-noise ratio.

    Science.gov (United States)

    Tateishi, Akito; Coleman, Sarah K; Migita, Satoshi; Keinänen, Kari; Haruyama, Tetsuya

    2012-01-01

    Cell-based biosensing is a "smart" way to obtain efficacy-information on the effect of applied chemical on cellular biological cascade. We have proposed an engineered post-synapse model cell-based biosensors to investigate the effects of chemicals on ionotropic glutamate receptor (GluR), which is a focus of attention as a molecular target for clinical neural drug discovery. The engineered model cell has several advantages over native cells, including improved ease of handling and better reproducibility in the application of cell-based biosensors. However, in general, cell-based biosensors often have low signal-to-noise (S/N) ratios due to the low level of cellular responses. In order to obtain a higher S/N ratio in model cells, we have attempted to design a tactic model cell with elevated cellular response. We have revealed that the increase GluR expression level is not directly connected to the amplification of cellular responses because the saturation of surface expression of GluR, leading to a limit on the total ion influx. Furthermore, coexpression of GluR with a voltage-gated potassium channel increased Ca(2+) ion influx beyond levels obtained with saturating amounts of GluR alone. The construction of model cells based on strategy of amplifying ion flux per individual receptors can be used to perform smart cell-based biosensing with an improved S/N ratio.

  13. Logistics Systems Engineer – Interdisciplinary Competence Model for Modern Education

    Directory of Open Access Journals (Sweden)

    Tarvo Niine

    2015-05-01

    Full Text Available Logistics is an interdisciplinary field of study. Modern logisticians need to integrate business management and administration skills with technology design, IT systems and other engineering fields. However, based on research of university curricula and competence standards in logistics, the engineering aspect is not represented to full potential. There are some treatments of logistician competences which relate to engineering, but not a modernized one with wide-spread recognition. This paper aims to explain the situation from the conceptual development point of view and suggests a competence profile for “logistics system engineer”, which introduces the viewpoint of systems engineering into logistics. For that purpose, the paper analyses requirements of various topical competence models and merges the introductory competences of systems engineering into logistics. In current interpretation, logistics systems engineering view integrates networks, technologies and ICT, process and service design and offers broader interdisciplinary approach. Another term suitable for this field would be intelligent logistics. The practical implication of such a competence profile is to utilize it in curriculum development and also present it as an occupational standard. The academic relevance of such concept is to offer a specific way to differentiate education in logistics.

  14. FPGA implementation of predictive degradation model for engine oil lifetime

    Science.gov (United States)

    Idros, M. F. M.; Razak, A. H. A.; Junid, S. A. M. Al; Suliman, S. I.; Halim, A. K.

    2018-03-01

    This paper presents the implementation of linear regression model for degradation prediction on Register Transfer Logic (RTL) using QuartusII. A stationary model had been identified in the degradation trend for the engine oil in a vehicle in time series method. As for RTL implementation, the degradation model is written in Verilog HDL and the data input are taken at a certain time. Clock divider had been designed to support the timing sequence of input data. At every five data, a regression analysis is adapted for slope variation determination and prediction calculation. Here, only the negative value are taken as the consideration for the prediction purposes for less number of logic gate. Least Square Method is adapted to get the best linear model based on the mean values of time series data. The coded algorithm has been implemented on FPGA for validation purposes. The result shows the prediction time to change the engine oil.

  15. Thermodynamics of Paint Related Systems with Engineering Models

    DEFF Research Database (Denmark)

    Lindvig, Thomas; Michelsen, Michael Locht; Kontogeorgis, Georgios

    2001-01-01

    to solid surfaces and drying. Many engineering models have been applied over the last decades for solutions with commoditity polymers. In this work the performance of some of these models is investigated for paint-related systems, focusing on those drying by the so-called " lacquer mechanism " (evaporation......Paints are complex materials composed of polymers (binders) dissolved in one or more solvents, pigments, and other additives. The thermodynamics of such systems is essential, for example, for selecting improved solvents and understanding a number of phenomena related especially! to adhesion...... that, despite the uncertainties involved, several models yield reasonably accurate activity coefficients, even at infinite dilution. Thus, engineering models may be useful for solvent selection via semiempirical rules of thumb, which are based on thermodynamic considerations....

  16. Engine Performance Test of the 1975 Chrysler - Nissan Model CN633 Diesel Engine

    Science.gov (United States)

    1975-09-01

    An engine test of the Chrysler-Nissan Model CN633 diesel engine was performed to determine its steady-state fuel consumption and emissions (HC, CO, NOx) maps. The data acquired are summarized in this report.

  17. Real Time Engineering Analysis Based on a Generative Component Implementation

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Klitgaard, Jens

    2007-01-01

    The present paper outlines the idea of a conceptual design tool with real time engineering analysis which can be used in the early conceptual design phase. The tool is based on a parametric approach using Generative Components with embedded structural analysis. Each of these components uses...... without jumping from aesthetics to structural digital design tools and back, but to work with both simultaneously and real time. The engineering level of knowledge is incorporated at a conceptual thinking level, i.e. qualitative information is used in stead of using quantitative information. An example...... with a static determinate roof structure modelled by beam components is given. The example outlines the idea of the tool for conceptual design in early phase of a multidisciplinary design process between architecture and structural engineering....

  18. Powder-based 3D printing for bone tissue engineering.

    Science.gov (United States)

    Brunello, G; Sivolella, S; Meneghello, R; Ferroni, L; Gardin, C; Piattelli, A; Zavan, B; Bressan, E

    2016-01-01

    Bone tissue engineered 3-D constructs customized to patient-specific needs are emerging as attractive biomimetic scaffolds to enhance bone cell and tissue growth and differentiation. The article outlines the features of the most common additive manufacturing technologies (3D printing, stereolithography, fused deposition modeling, and selective laser sintering) used to fabricate bone tissue engineering scaffolds. It concentrates, in particular, on the current state of knowledge concerning powder-based 3D printing, including a description of the properties of powders and binder solutions, the critical phases of scaffold manufacturing, and its applications in bone tissue engineering. Clinical aspects and future applications are also discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Spray/wall interaction models for multidimensional engine simulation

    Energy Technology Data Exchange (ETDEWEB)

    Han, Z.; Trigui, N. [Ford Motor Co., Dearborn, MI (United States); Xu, Z. [ICEM CFD Engineering, Livonia, MI (United States)

    2000-02-01

    Models were developed to describe the spray wall impingement processes that take place in internal combustion engines. In this report focus is placed on the model formulation and experiment assessment of the spray/wall interaction submodels. It is identified that the Leidenfrost phenomenon is very unlikely to occur in a spark ignition (SI) engine including stratified-charge operation in a direct injection spark ignition (DISI) engine. A more comprehensive splashing/deposition threshold function is proposed to include the effects of surface roughness and pre-existing liquid film. Based on the wave phenomena observed on the surface of the liquid crown formed during drop impingement, a new splash breakup model is developed using linear instability analysis. The predicted drop size agrees well with available single-drop impingement experimental data. A new formulation for the post-impingement droplet velocity is also given which uses statistical sampling and jet impingement theory. The proposed models were assessed by comparing computations with two sets of experimental sprays impinging on a flat plate with the use of a pintle nozzle injector for port fuel injection (PFI) engines. The computed spray shape, normal and tangential penetration and droplet size show good agreement with experimental data. (Author)

  20. Problems in event based engine control

    DEFF Research Database (Denmark)

    Hendricks, Elbert; Jensen, Michael; Chevalier, Alain Marie Roger

    1994-01-01

    Physically a four cycle spark ignition engine operates on the basis of four engine processes or events: intake, compression, ignition (or expansion) and exhaust. These events each occupy approximately 180° of crank angle. In conventional engine controllers, it is an accepted practice to sample...... problems on accurate air/fuel ratio control of a spark ignition (SI) engine....

  1. Validation of GPU based TomoTherapy dose calculation engine.

    Science.gov (United States)

    Chen, Quan; Lu, Weiguo; Chen, Yu; Chen, Mingli; Henderson, Douglas; Sterpin, Edmond

    2012-04-01

    The graphic processing unit (GPU) based TomoTherapy convolution/superposition(C/S) dose engine (GPU dose engine) achieves a dramatic performance improvement over the traditional CPU-cluster based TomoTherapy dose engine (CPU dose engine). Besides the architecture difference between the GPU and CPU, there are several algorithm changes from the CPU dose engine to the GPU dose engine. These changes made the GPU dose slightly different from the CPU-cluster dose. In order for the commercial release of the GPU dose engine, its accuracy has to be validated. Thirty eight TomoTherapy phantom plans and 19 patient plans were calculated with both dose engines to evaluate the equivalency between the two dose engines. Gamma indices (Γ) were used for the equivalency evaluation. The GPU dose was further verified with the absolute point dose measurement with ion chamber and film measurements for phantom plans. Monte Carlo calculation was used as a reference for both dose engines in the accuracy evaluation in heterogeneous phantom and actual patients. The GPU dose engine showed excellent agreement with the current CPU dose engine. The majority of cases had over 99.99% of voxels with Γ(1%, 1 mm) GPU dose engine also showed similar degree of accuracy in heterogeneous media as the current TomoTherapy dose engine. It is verified and validated that the ultrafast TomoTherapy GPU dose engine can safely replace the existing TomoTherapy cluster based dose engine without degradation in dose accuracy.

  2. Systems Engineering Model and Training Application for Desktop Environment

    Science.gov (United States)

    May, Jeffrey T.

    2010-01-01

    Provide a graphical user interface based simulator for desktop training, operations and procedure development and system reference. This simulator allows for engineers to train and further understand the dynamics of their system from their local desktops. It allows the users to train and evaluate their system at a pace and skill level based on the user's competency and from a perspective based on the user's need. The simulator will not require any special resources to execute and should generally be available for use. The interface is based on a concept of presenting the model of the system in ways that best suits the user's application or training needs. The three levels of views are Component View, the System View (overall system), and the Console View (monitor). These views are portals into a single model, so changing the model from one view or from a model manager Graphical User Interface will be reflected on all other views.

  3. Genetically engineered livestock for biomedical models.

    Science.gov (United States)

    Rogers, Christopher S

    2016-06-01

    To commemorate Transgenic Animal Research Conference X, this review summarizes the recent progress in developing genetically engineered livestock species as biomedical models. The first of these conferences was held in 1997, which turned out to be a watershed year for the field, with two significant events occurring. One was the publication of the first transgenic livestock animal disease model, a pig with retinitis pigmentosa. Before that, the use of livestock species in biomedical research had been limited to wild-type animals or disease models that had been induced or were naturally occurring. The second event was the report of Dolly, a cloned sheep produced by somatic cell nuclear transfer. Cloning subsequently became an essential part of the process for most of the models developed in the last 18 years and is stilled used prominently today. This review is intended to highlight the biomedical modeling achievements that followed those key events, many of which were first reported at one of the previous nine Transgenic Animal Research Conferences. Also discussed are the practical challenges of utilizing livestock disease models now that the technical hurdles of model development have been largely overcome.

  4. Engineering models for catastrophe risk and their application to insurance

    Science.gov (United States)

    Dong, Weimin

    2002-06-01

    Internationally earthquake insurance, like all other insurance (fire, auto), adopted actuarial approach in the past, which is, based on historical loss experience to determine insurance rate. Due to the fact that earthquake is a rare event with severe consequence, irrational determination of premium rate and lack of understanding scale of potential loss led to many insurance companies insolvent after Northridge earthquake in 1994. Along with recent advances in earth science, computer science and engineering, computerized loss estimation methodologies based on first principles have been developed to the point that losses from destructive earthquakes can be quantified with reasonable accuracy using scientific modeling techniques. This paper intends to introduce how engineering models can assist to quantify earthquake risk and how insurance industry can use this information to manage their risk in the United States and abroad.

  5. Next-generation genome-scale models for metabolic engineering

    DEFF Research Database (Denmark)

    King, Zachary A.; Lloyd, Colton J.; Feist, Adam M.

    2015-01-01

    Constraint-based reconstruction and analysis (COBRA) methods have become widely used tools for metabolic engineering in both academic and industrial laboratories. By employing a genome-scale in silico representation of the metabolic network of a host organism, COBRA methods can be used to predict...... optimal genetic modifications that improve the rate and yield of chemical production. A new generation of COBRA models and methods is now being developed. -. encompassing many biological processes and simulation strategies. -. and next-generation models enable new types of predictions. Here, three key...... examples of applying COBRA methods to strain optimization are presented and discussed. Then, an outlook is provided on the next generation of COBRA models and the new types of predictions they will enable for systems metabolic engineering....

  6. Reverse engineering systems models of regulation: discovery, prediction and mechanisms.

    Science.gov (United States)

    Ashworth, Justin; Wurtmann, Elisabeth J; Baliga, Nitin S

    2012-08-01

    Biological systems can now be understood in comprehensive and quantitative detail using systems biology approaches. Putative genome-scale models can be built rapidly based upon biological inventories and strategic system-wide molecular measurements. Current models combine statistical associations, causative abstractions, and known molecular mechanisms to explain and predict quantitative and complex phenotypes. This top-down 'reverse engineering' approach generates useful organism-scale models despite noise and incompleteness in data and knowledge. Here we review and discuss the reverse engineering of biological systems using top-down data-driven approaches, in order to improve discovery, hypothesis generation, and the inference of biological properties. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Engine control system having speed-based timing

    Science.gov (United States)

    Willi, Martin L [Dunlap, IL; Fiveland, Scott B [Metamora, IL; Montgomery, David T [Edelstein, IL; Gong, Weidong [Dunlap, IL

    2012-02-14

    A control system for an engine having a cylinder is disclosed having an engine valve movable to regulate a fluid flow of the cylinder and an actuator associated with the engine valve. The control system also has a controller in communication with the actuator. The controller is configured to receive a signal indicative of engine speed and compare the engine speed signal with a desired engine speed. The controller is also configured to selectively regulate the actuator to adjust a timing of the engine valve to control an amount of air/fuel mixture delivered to the cylinder based on the comparison.

  8. Development of Systems Engineering Model for Spent Fuel Extraction Process

    International Nuclear Information System (INIS)

    Sun, Lijian; Royyuru, Haritha; Hsieh, Hsuan-Tsung 'Sean'; Chen, Yitung; Clarksean, Randy; Vandegrift, George; Copple, Jackie; Laidler, James

    2004-01-01

    The mission of the Transmutation Research Program (TRP) at University of Nevada, Las Vegas (UNLV) is to establish a nuclear engineering test bed that can carry out effective transmutation and advanced reactor research and development effort. The Nevada Center for Advanced Computational Methods (NCACM) at UNLV is currently developing the systems engineering model, TRPSEMPro (Transmutation Research Program System Engineering Model Project, that provides process optimization through the automatic adjustment on input parameters, such as feed compositions, stages, flow rates, etc., based on the extraction efficiency of components and concerned output factors. An object-oriented programming (OOP) is considered. Such systems engineering model consists of task manager, task integration and solution monitor modules. A MS SQL server database is implemented for managing data flow from optimization processing. Task manager coordinates and interacts with other two modules. Task integration module works as a flowsheet constructor that builds task hierarchy, input parameter values and constrains. Task solution monitor component presents both in-progress and final outputs in tabulated and graphical formats. The system can monitor parameter justification outputs from optimization toolbox developed by Mathworks' MatLab commercial software. While initial parameter constraint identifications for using optimization process is tedious and time-consuming, the interface also provides a multiple-run process that executes a design matrix without invoking any optimization module. Experimental reports can be flexibly generated through database query and formatting. (authors)

  9. Mean Value Engine Modelling of an SI Engine with EGR

    DEFF Research Database (Denmark)

    Føns, Michael; Müller, Martin; Chevalier, Alain

    1999-01-01

    Recirculation (EGR). The purpose of this paper is to present a modified MVEM which includes EGR in a physical way. It has been tested using newly developed, very fast manifold pressure, manifold temperature, port and EGR mass flow sensors. Reasonable agreement has been obtained on an experimental engine...

  10. Transforming System Engineering through Model-Centric Engineering

    Science.gov (United States)

    2015-11-18

    Richard Yates Bill Brickner Fatma Dandashi Keith Carter Rob Cloutier Bhawana Sharma Fran Chamberlain Leslie Taylor Sara Shaddix Brad Kidwell Geethesh... Blakely 1 EXECUTIVE SUMMARY This is the final report of the Systems Engineering Research Center (SERC) research task RT-141 that

  11. An engineering based on love: responding to climate change

    International Nuclear Information System (INIS)

    Catalano, G.D.

    2009-01-01

    'Full text:' Recent death of a beloved member of my family has served as a catalyst for my reflection on not only the nature of my work but also upon my approach to the issue of reforms in engineering and engineering education which are desperately needed. In engineering we often speak of development. Far too often it seems that the model used in engineering education is education for profit making. The ultimate goal is economic growth with no interest in peace, social or environmental justice or wealth distribution. Such a model ignores inequalities, has contempt for the arts and literature, promotes group think, needs docile students and de-emphasizes critical thinking. I would like to offer a different paradigm for engineering education, one which has as its priority the development of not only the human spirit but also the rest of the natural world. Using such a paradigm, each and every being matters, groups are disaggregated into individuals and equal respect exists for each individual. Ultimately the goal of such an education would be to enable each of us to transcend our own particular situations and imagine a global society which is based upon equality and on love. Key elements of an education based upon love would include the capacity for true, rigorous critical thought, the development of a culture in which individual dissent is honored and revered and in which each of us considers our self a citizen of the Earth. Lastly an education based upon love would enable each of us to develop our own individual narrative of moral imagination, that is, to develop the ability to be in another's shoes, to cultivate our inner eye of seeing and knowing and to overcome the blindness that we have all become far too accustomed. (author)

  12. An engineering based on love: responding to climate change

    Energy Technology Data Exchange (ETDEWEB)

    Catalano, G.D. [State Univ. of New York at Binghamton (United States)

    2009-07-01

    'Full text:' Recent death of a beloved member of my family has served as a catalyst for my reflection on not only the nature of my work but also upon my approach to the issue of reforms in engineering and engineering education which are desperately needed. In engineering we often speak of development. Far too often it seems that the model used in engineering education is education for profit making. The ultimate goal is economic growth with no interest in peace, social or environmental justice or wealth distribution. Such a model ignores inequalities, has contempt for the arts and literature, promotes group think, needs docile students and de-emphasizes critical thinking. I would like to offer a different paradigm for engineering education, one which has as its priority the development of not only the human spirit but also the rest of the natural world. Using such a paradigm, each and every being matters, groups are disaggregated into individuals and equal respect exists for each individual. Ultimately the goal of such an education would be to enable each of us to transcend our own particular situations and imagine a global society which is based upon equality and on love. Key elements of an education based upon love would include the capacity for true, rigorous critical thought, the development of a culture in which individual dissent is honored and revered and in which each of us considers our self a citizen of the Earth. Lastly an education based upon love would enable each of us to develop our own individual narrative of moral imagination, that is, to develop the ability to be in another's shoes, to cultivate our inner eye of seeing and knowing and to overcome the blindness that we have all become far too accustomed. (author)

  13. Engineering models for merging wakes in wind farm optimization applications

    DEFF Research Database (Denmark)

    Machefaux, Ewan; Larsen, Gunner Chr.; Murcia Leon, Juan Pablo

    2015-01-01

    The present paper deals with validation of 4 different engineering wake superposition approaches against detailed CFD simulations and covering different turbine interspacing, ambient turbulence intensities and mean wind speeds. The first engineering model is a simple linear superposition of wake ...

  14. Career Persistence Model for Female Engineers in the Indonesian Context

    Directory of Open Access Journals (Sweden)

    Lies Dahlia

    2017-08-01

    Full Text Available Extant studies about female engineers have suggested their career persistency in the engineering career is influenced by the workplace, which is characterized by male dominated culture making them feel marginalized. In Indonesia, similar studies for reference are limited. This paper is based on an exploratory quantitative study using a questionnaire developed based on the Career Persistence Model. This paper is based on an empirical exploratory quantitative study by adopting Buse’s et al. Career Persistence Model (2013. The intention is to contribute to the literature in the context of Indonesia. It explores the Indonesian cultural dimensions and investigates their relationship to the roles of women in family, society and the workplace, and how women manage to navigate barriers to avoid taking alternative career paths. Contrary to extant studies, findings show women feel equally treated to men in the workplace, however some work demands may hinder. The strong acknowledgement of one’s roles in this collective society outdoes the opinions that the Islamic jurisprudence (fiqh has marginalized empowerment of women, resulting in gender-based injustices and discrimination. Future studies should look into social supports at the workplace in an attempt to retain and increase the share of women in the engineering career in Indonesia.

  15. Four-Stroke, Internal Combustion Engine Performance Modeling

    Science.gov (United States)

    Wagner, Richard C.

    In this thesis, two models of four-stroke, internal combustion engines are created and compared. The first model predicts the intake and exhaust processes using isentropic flow equations augmented by discharge coefficients. The second model predicts the intake and exhaust processes using a compressible, time-accurate, Quasi-One-Dimensional (Q1D) approach. Both models employ the same heat release and reduced-order modeling of the cylinder charge. Both include friction and cylinder loss models so that the predicted performance values can be compared to measurements. The results indicate that the isentropic-based model neglects important fluid mechanics and returns inaccurate results. The Q1D flow model, combined with the reduced-order model of the cylinder charge, is able to capture the dominant intake and exhaust fluid mechanics and produces results that compare well with measurement. Fluid friction, convective heat transfer, piston ring and skirt friction and temperature-varying specific heats in the working fluids are all shown to be significant factors in engine performance predictions. Charge blowby is shown to play a lesser role.

  16. Tool for the Synthesis of Mechanisms of New Engines Based on Dasy

    Directory of Open Access Journals (Sweden)

    Richtr David

    2017-12-01

    Full Text Available The article presents a tool for the synthesis of engine mechanisms based on DASY and the use thereof for designing the parameters of an experimental single-cylinder engine. The tool includes a parametric engine model based on DASY. The model will make it possible to simulate the engine thermodynamics and its mechanisms. It consists of sub-models which deal with the thermodynamics, kinematics and dynamics of the valve timing mechanism, its belt drive, and hydraulic circuit for camshaft adjustment. The methodologies of synthesis of mechanisms were used to determine the values of the calibration parameters. The parameters of the sub-models were subsequently validated by experimental data, and the values thereof are included in DASY. The sub-models were used to assemble the model of an experimental single-cylinder engine which validates the design thereof, makes it possible to optimize its parameters and predict its behavior in different simulated conditions.

  17. Zero-dimensional mathematical model of the torch ignited engine

    International Nuclear Information System (INIS)

    Cruz, Igor William Santos Leal; Alvarez, Carlos Eduardo Castilla; Teixeira, Alysson Fernandes; Valle, Ramon Molina

    2016-01-01

    Highlights: • Publications about the torch ignition system are mostly CFD or experimental research. • A zero-dimensional mathematical model is presented. • The model is based on classical thermodynamic equations. • Approximations are based on empirical functions. • The model is applied to a prototype by means of a computer code. - Abstract: Often employed in the analysis of conventional SI and CI engines, mathematical models can also be applied to engines with torch ignition, which have been researched almost exclusively by CFD or experimentally. The objective of this work is to describe the development and application of a zero-dimensional model of the compression and power strokes of a torch ignited engine. It is an initial analysis that can be used as a basis for future models. The processes of compression, combustion and expansion were described mathematically and applied to an existing prototype by means of a computer code written in MATLAB language. Conservation of energy and mass and the ideal gas law were used in determining gas temperature, pressure, and mass flow rate within the cylinder. Gas motion through the orifice was modelled as an isentropic compressible flow. The thermodynamic properties of the mixture were found by a weighted arithmetic mean of the data for each component, computed by polynomial functions of temperature. Combustion was modelled by the Wiebe function. Heat transfer to the cylinder walls was estimated by Annand’s correlations. Results revealed the behaviour of pressure, temperature, jet velocity, energy transfer, thermodynamic properties, among other variables, and how some of these are influenced by others.

  18. Social Engineering Attack Detection Model: SEADMv2

    CSIR Research Space (South Africa)

    Mouton, F

    2015-10-01

    Full Text Available and is only able to cater for social engineering attacks that use bidirectional communication. Previous research discovered that social engineering attacks can be classified into three different categories, namely attacks that utilise bidirectional...

  19. Diagrammatic Models in the Engineering Sciences.

    NARCIS (Netherlands)

    Boon, Mieke

    2008-01-01

    This paper is concerned with scientific reasoning in the engineering sciences. Engineering sciences aim at explaining, predicting and describing physical phenomena occurring in technological devices. The focus of this paper is on mathematical description. These mathematical descriptions are

  20. Computational modeling for eco engineering: Making the connections between engineering and ecology (Invited)

    Science.gov (United States)

    Bowles, C.

    2013-12-01

    Ecological engineering, or eco engineering, is an emerging field in the study of integrating ecology and engineering, concerned with the design, monitoring, and construction of ecosystems. According to Mitsch (1996) 'the design of sustainable ecosystems intends to integrate human society with its natural environment for the benefit of both'. Eco engineering emerged as a new idea in the early 1960s, and the concept has seen refinement since then. As a commonly practiced field of engineering it is relatively novel. Howard Odum (1963) and others first introduced it as 'utilizing natural energy sources as the predominant input to manipulate and control environmental systems'. Mtisch and Jorgensen (1989) were the first to define eco engineering, to provide eco engineering principles and conceptual eco engineering models. Later they refined the definition and increased the number of principles. They suggested that the goals of eco engineering are: a) the restoration of ecosystems that have been substantially disturbed by human activities such as environmental pollution or land disturbance, and b) the development of new sustainable ecosystems that have both human and ecological values. Here a more detailed overview of eco engineering is provided, particularly with regard to how engineers and ecologists are utilizing multi-dimensional computational models to link ecology and engineering, resulting in increasingly successful project implementation. Descriptions are provided pertaining to 1-, 2- and 3-dimensional hydrodynamic models and their use at small- and large-scale applications. A range of conceptual models that have been developed to aid the in the creation of linkages between ecology and engineering are discussed. Finally, several case studies that link ecology and engineering via computational modeling are provided. These studies include localized stream rehabilitation, spawning gravel enhancement on a large river system, and watershed-wide floodplain modeling of

  1. Computational modeling, optimization and manufacturing simulation of advanced engineering materials

    CERN Document Server

    2016-01-01

    This volume presents recent research work focused in the development of adequate theoretical and numerical formulations to describe the behavior of advanced engineering materials.  Particular emphasis is devoted to applications in the fields of biological tissues, phase changing and porous materials, polymers and to micro/nano scale modeling. Sensitivity analysis, gradient and non-gradient based optimization procedures are involved in many of the chapters, aiming at the solution of constitutive inverse problems and parameter identification. All these relevant topics are exposed by experienced international and inter institutional research teams resulting in a high level compilation. The book is a valuable research reference for scientists, senior undergraduate and graduate students, as well as for engineers acting in the area of computational material modeling.

  2. Formal Model-Driven Engineering: Generating Data and Behavioural Components

    Directory of Open Access Journals (Sweden)

    Chen-Wei Wang

    2012-12-01

    Full Text Available Model-driven engineering is the automatic production of software artefacts from abstract models of structure and functionality. By targeting a specific class of system, it is possible to automate aspects of the development process, using model transformations and code generators that encode domain knowledge and implementation strategies. Using this approach, questions of correctness for a complex, software system may be answered through analysis of abstract models of lower complexity, under the assumption that the transformations and generators employed are themselves correct. This paper shows how formal techniques can be used to establish the correctness of model transformations used in the generation of software components from precise object models. The source language is based upon existing, formal techniques; the target language is the widely-used SQL notation for database programming. Correctness is established by giving comparable, relational semantics to both languages, and checking that the transformations are semantics-preserving.

  3. Artificial Intelligence Software Engineering (AISE) model

    Science.gov (United States)

    Kiss, Peter A.

    1990-01-01

    The American Institute of Aeronautics and Astronautics has initiated a committee on standards for Artificial Intelligence. Presented are the initial efforts of one of the working groups of that committee. A candidate model is presented for the development life cycle of knowledge based systems (KBSs). The intent is for the model to be used by the aerospace community and eventually be evolved into a standard. The model is rooted in the evolutionary model, borrows from the spiral model, and is embedded in the standard Waterfall model for software development. Its intent is to satisfy the development of both stand-alone and embedded KBSs. The phases of the life cycle are shown and detailed as are the review points that constitute the key milestones throughout the development process. The applicability and strengths of the model are discussed along with areas needing further development and refinement by the aerospace community.

  4. Proposing an Evidence-Based Strategy for Software Requirements Engineering.

    Science.gov (United States)

    Lindoerfer, Doris; Mansmann, Ulrich

    2016-01-01

    This paper discusses an evidence-based approach to software requirements engineering. The approach is called evidence-based, since it uses publications on the specific problem as a surrogate for stakeholder interests, to formulate risks and testing experiences. This complements the idea that agile software development models are more relevant, in which requirements and solutions evolve through collaboration between self-organizing cross-functional teams. The strategy is exemplified and applied to the development of a Software Requirements list used to develop software systems for patient registries.

  5. Engineering Glass Passivation Layers -Model Results

    Energy Technology Data Exchange (ETDEWEB)

    Skorski, Daniel C.; Ryan, Joseph V.; Strachan, Denis M.; Lepry, William C.

    2011-08-08

    The immobilization of radioactive waste into glass waste forms is a baseline process of nuclear waste management not only in the United States, but worldwide. The rate of radionuclide release from these glasses is a critical measure of the quality of the waste form. Over long-term tests and using extrapolations of ancient analogues, it has been shown that well designed glasses exhibit a dissolution rate that quickly decreases to a slow residual rate for the lifetime of the glass. The mechanistic cause of this decreased corrosion rate is a subject of debate, with one of the major theories suggesting that the decrease is caused by the formation of corrosion products in such a manner as to present a diffusion barrier on the surface of the glass. Although there is much evidence of this type of mechanism, there has been no attempt to engineer the effect to maximize the passivating qualities of the corrosion products. This study represents the first attempt to engineer the creation of passivating phases on the surface of glasses. Our approach utilizes interactions between the dissolving glass and elements from the disposal environment to create impermeable capping layers. By drawing from other corrosion studies in areas where passivation layers have been successfully engineered to protect the bulk material, we present here a report on mineral phases that are likely have a morphological tendency to encrust the surface of the glass. Our modeling has focused on using the AFCI glass system in a carbonate, sulfate, and phosphate rich environment. We evaluate the minerals predicted to form to determine the likelihood of the formation of a protective layer on the surface of the glass. We have also modeled individual ions in solutions vs. pH and the addition of aluminum and silicon. These results allow us to understand the pH and ion concentration dependence of mineral formation. We have determined that iron minerals are likely to form a complete incrustation layer and we plan

  6. The Implementation and Evaluation of a Project-Oriented Problem-Based Learning Module in a First Year Engineering Programme

    Science.gov (United States)

    McLoone, Seamus C.; Lawlor, Bob J.; Meehan, Andrew R.

    2016-01-01

    This paper describes how a circuits-based project-oriented problem-based learning educational model was integrated into the first year of a Bachelor of Engineering in Electronic Engineering programme at Maynooth University, Ireland. While many variations of problem based learning exist, the presented model is closely aligned with the model used in…

  7. Journal of Modeling, Design and Management of Engineering ...

    African Journals Online (AJOL)

    The Journal of Modeling, Design & Management of Engineering Systems publishes original research reports, short communications, and critical reviews in any branch of engineering and allied fields such as applied mathematics, applied physics, applied chemistry and ... Department of Mechanical Engineering, University ...

  8. Teaching Agile Software Engineering Using Problem-Based Learning

    Science.gov (United States)

    El-Khalili, Nuha H.

    2013-01-01

    Many studies have reported the utilization of Problem-Based Learning (PBL) in teaching Software Engineering courses. However, these studies have different views of the effectiveness of PBL. This paper presents the design of an Advanced Software Engineering course for undergraduate Software Engineering students that uses PBL to teach them Agile…

  9. Analytical Study of Component Based Software Engineering

    OpenAIRE

    Iqbaldeep Kaur; Parvinder S. Sandhu; Hardeep Singh; Vandana Saini

    2009-01-01

    This paper is a survey of current component-based software technologies and the description of promotion and inhibition factors in CBSE. The features that software components inherit are also discussed. Quality Assurance issues in componentbased software are also catered to. The feat research on the quality model of component based system starts with the study of what the components are, CBSE, its development life cycle and the pro & cons of CBSE. Various attributes are s...

  10. Civil engineering: EDF needs for concrete modelling

    International Nuclear Information System (INIS)

    Didry, O.; Gerard, B.; Bui, D.

    1997-01-01

    Concrete structures which are encountered at EDF, like all civil engineering structures, age. In order to adapt the maintenance conditions of these structures, particularly to extend their service life, and also to prepare constructions of future structures, tools for predicting the behaviour of these structures in their environment should be available. For EDF the technical risks are high and consequently very appropriate R and D actions are required. In this context the Direction des Etudes et Recherches (DER) has developed a methodology for analysing concrete structure behaviour modelling. This approach has several aims: - making a distinction between the problems which refer to the existing models and those which require R and D; - displaying disciplinary links between different problems encountered on EDF structures (non-linear mechanical, chemical - hydraulic - mechanical coupling, etc); - listing of the existing tools and positioning the DER 'Aster' finite element code among them. This document is a state of the art of scientific knowledge intended to shed light on the fields in which one should be involved when there is, on one part a strong requirement on the side of structure operators, and on the other one, the present tools do not allow this requirement to be satisfactorily met. The analysis has been done on 12 scientific subjects: 1) Hydration of concrete at early ages: exothermicity, hardening, autogenous shrinkage; 2) Drying and drying shrinkage; 3) Alkali-silica reaction and bulky stage formation; 4) Long term deterioration by leaching; 5) Ionic diffusion and associated attacks: the chlorides case; 6) Permeability / tightness of concrete; 7) Concretes -nonlinear behaviour and cracking (I): contribution of the plasticity models; 8) Concretes - nonlinear behaviour and cracking (II): contribution of the damage models; 9) Concretes - nonlinear behaviour and cracking (III): the contribution of the probabilistic analysis model; 10) Delayed behaviour of

  11. Underwater striling engine design with modified one-dimensional model

    OpenAIRE

    Li, Daijin; Qin, Kan; Luo, Kai

    2015-01-01

    Stirling engines are regarded as an efficient and promising power system for underwater devices. Currently, many researches on one-dimensional model is used to evaluate thermodynamic performance of Stirling engine, but in which there are still some aspects which cannot be modeled with proper mathematical models such as mechanical loss or auxiliary power. In this paper, a four-cylinder double-acting Stirling engine for Unmanned Underwater Vehicles (UUVs) is discussed. And a one-dimensional mod...

  12. Dimensionality reduction for uncertainty quantification of nuclear engineering models.

    Energy Technology Data Exchange (ETDEWEB)

    Roderick, O.; Wang, Z.; Anitescu, M. (Mathematics and Computer Science)

    2011-01-01

    The task of uncertainty quantification consists of relating the available information on uncertainties in the model setup to the resulting variation in the outputs of the model. Uncertainty quantification plays an important role in complex simulation models of nuclear engineering, where better understanding of uncertainty results in greater confidence in the model and in the improved safety and efficiency of engineering projects. In our previous work, we have shown that the effect of uncertainty can be approximated by polynomial regression with derivatives (PRD): a hybrid regression method that uses first-order derivatives of the model output as additional fitting conditions for a polynomial expansion. Numerical experiments have demonstrated the advantage of this approach over classical methods of uncertainty analysis: in precision, computational efficiency, or both. To obtain derivatives, we used automatic differentiation (AD) on the simulation code; hand-coded derivatives are acceptable for simpler models. We now present improvements on the method. We use a tuned version of the method of snapshots, a technique based on proper orthogonal decomposition (POD), to set up the reduced order representation of essential information on uncertainty in the model inputs. The automatically obtained sensitivity information is required to set up the method. Dimensionality reduction in combination with PRD allows analysis on a larger dimension of the uncertainty space (>100), at modest computational cost.

  13. Survey of Traceability Approaches in Model-Driven Engineering

    NARCIS (Netherlands)

    Galvao, I.; Göknil, Arda

    2007-01-01

    Models have been used in various engineering fields to help managing complexity and represent information in different abstraction levels, according to specific notations and stakeholder's viewpoints. Model-Driven Engineering (MDE) gives the basic principles for the use of models as primary

  14. Interactive Computer Based Lessons for Engineering Education

    Science.gov (United States)

    Bennett, James A.

    1975-01-01

    Discusses the advantages and disadvantages of three types of computer instruction in engineering education: tutorial, design, and simulations. Includes comments on efficiency, student acceptance, and scheduling problems. (MLH)

  15. Engineering virtual-environment-based training simulators

    Science.gov (United States)

    Jense, Hans; Kuijper, Frido

    1998-04-01

    While the potential of Virtual Environments (VE's) for training simulators has been recognized right from the start of the emergence of the technology, to date most VE systems that claim to be training simulators have been developed in an adhoc fashion. Based on requirements of the Royal Netherlands Army and Air Force, we have recently developed VE based training simulators following basic systems engineering practice. This paper reports on our approach in general, and specifically focuses on two examples. The first is a distributed VE system for training Forward Air Controllers (FAC's). This system comprises an immersive VE for the FAC trainee, as well as a number of other components, all interconnected in a network infrastructure utilizing the DIS/HLA standard protocols for distributed simulation. The prototype VE FAC simulator is currently being used in the training program of the Netherlands Integrated Air/Ground Operations School. Feedback from the users is being collected as input for a follow-on development activity. A second development is aimed at the evaluation of VE technology for training gunnery procedures with the Stinger man-portable air-defense system. In this project, a system is being developed that enables us to evaluate a number of different configurations with respect to both human and systems performance characteristics.

  16. Applied data analysis and modeling for energy engineers and scientists

    CERN Document Server

    Reddy, T Agami

    2011-01-01

    ""Applied Data Analysis and Modeling for Energy Engineers and Scientists"" discusses mathematical models, data analysis, and decision analysis in modeling. The approach taken in this volume focuses on the modeling and analysis of thermal systems in an engineering environment, while also covering a number of other critical areas. Other material covered includes the tools that researchers and engineering professionals will need in order to explore different analysis methods, use critical assessment skills and reach sound engineering conclusions. The book also covers process and system design and

  17. Developing a Consensus-Driven, Core Competency Model to Shape Future Audio Engineering Technology Curriculum: A Web-Based Modified Delphi Study

    Science.gov (United States)

    Tough, David T.

    2009-01-01

    The purpose of this online study was to create a ranking of essential core competencies and technologies required by AET (audio engineering technology) programs 10 years in the future. The study was designed to facilitate curriculum development and improvement in the rapidly expanding number of small to medium sized audio engineering technology…

  18. Combustion Model and Control Parameter Optimization Methods for Single Cylinder Diesel Engine

    Directory of Open Access Journals (Sweden)

    Bambang Wahono

    2014-01-01

    Full Text Available This research presents a method to construct a combustion model and a method to optimize some control parameters of diesel engine in order to develop a model-based control system. The construction purpose of the model is to appropriately manage some control parameters to obtain the values of fuel consumption and emission as the engine output objectives. Stepwise method considering multicollinearity was applied to construct combustion model with the polynomial model. Using the experimental data of a single cylinder diesel engine, the model of power, BSFC, NOx, and soot on multiple injection diesel engines was built. The proposed method succesfully developed the model that describes control parameters in relation to the engine outputs. Although many control devices can be mounted to diesel engine, optimization technique is required to utilize this method in finding optimal engine operating conditions efficiently beside the existing development of individual emission control methods. Particle swarm optimization (PSO was used to calculate control parameters to optimize fuel consumption and emission based on the model. The proposed method is able to calculate control parameters efficiently to optimize evaluation item based on the model. Finally, the model which added PSO then was compiled in a microcontroller.

  19. Real Time Engineering Analysis Based on a Generative component Implementation

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Klitgaard, Jens

    2007-01-01

    The present paper outlines the idea of a conceptual design tool with real time engineering analysis which can be used in the early conceptual design phase. The tool is based on a parametric approach using Generative Components with embedded structural analysis. Each of these components uses...... the geometry, material properties and fixed point characteristics to calculate the dimensions and subsequent feasibility of any architectural design. The proposed conceptual design tool provides the possibility for the architect to work with both the aesthetic as well as the structural aspects of architecture...... with a static determinate roof structure modelled by beam components is given. The example outlines the idea of the tool for conceptual design in early phase of a multidisciplinary design process between architecture and structural engineering....

  20. Building Information Modeling in engineering teaching

    DEFF Research Database (Denmark)

    Andersson, Niclas; Andersson, Pernille Hammar

    2010-01-01

    The application of Information and Communication Technology (ICT) in construction supports business as well as project processes by providing integrated systems for communication, administration, quantity takeoff, time scheduling, cost estimating, progress control among other things. The rapid....... In engineering education there is an obvious aim to provide students with sufficient disciplinary knowledge in science and engineering principles. The implementation of ICT in engineering education requires, however, that valuable time and teaching efforts are spent on adequate software training needed...

  1. Statistical Validation of Engineering and Scientific Models: Background

    International Nuclear Information System (INIS)

    Hills, Richard G.; Trucano, Timothy G.

    1999-01-01

    A tutorial is presented discussing the basic issues associated with propagation of uncertainty analysis and statistical validation of engineering and scientific models. The propagation of uncertainty tutorial illustrates the use of the sensitivity method and the Monte Carlo method to evaluate the uncertainty in predictions for linear and nonlinear models. Four example applications are presented; a linear model, a model for the behavior of a damped spring-mass system, a transient thermal conduction model, and a nonlinear transient convective-diffusive model based on Burger's equation. Correlated and uncorrelated model input parameters are considered. The model validation tutorial builds on the material presented in the propagation of uncertainty tutoriaI and uses the damp spring-mass system as the example application. The validation tutorial illustrates several concepts associated with the application of statistical inference to test model predictions against experimental observations. Several validation methods are presented including error band based, multivariate, sum of squares of residuals, and optimization methods. After completion of the tutorial, a survey of statistical model validation literature is presented and recommendations for future work are made

  2. Teaching learning based optimization algorithm and its engineering applications

    CERN Document Server

    Rao, R Venkata

    2016-01-01

    Describing a new optimization algorithm, the “Teaching-Learning-Based Optimization (TLBO),” in a clear and lucid style, this book maximizes reader insights into how the TLBO algorithm can be used to solve continuous and discrete optimization problems involving single or multiple objectives. As the algorithm operates on the principle of teaching and learning, where teachers influence the quality of learners’ results, the elitist version of TLBO algorithm (ETLBO) is described along with applications of the TLBO algorithm in the fields of electrical engineering, mechanical design, thermal engineering, manufacturing engineering, civil engineering, structural engineering, computer engineering, electronics engineering, physics and biotechnology. The book offers a valuable resource for scientists, engineers and practitioners involved in the development and usage of advanced optimization algorithms.

  3. Practical Techniques for Modeling Gas Turbine Engine Performance

    Science.gov (United States)

    Chapman, Jeffryes W.; Lavelle, Thomas M.; Litt, Jonathan S.

    2016-01-01

    The cost and risk associated with the design and operation of gas turbine engine systems has led to an increasing dependence on mathematical models. In this paper, the fundamentals of engine simulation will be reviewed, an example performance analysis will be performed, and relationships useful for engine control system development will be highlighted. The focus will be on thermodynamic modeling utilizing techniques common in industry, such as: the Brayton cycle, component performance maps, map scaling, and design point criteria generation. In general, these topics will be viewed from the standpoint of an example turbojet engine model; however, demonstrated concepts may be adapted to other gas turbine systems, such as gas generators, marine engines, or high bypass aircraft engines. The purpose of this paper is to provide an example of gas turbine model generation and system performance analysis for educational uses, such as curriculum creation or student reference.

  4. Transforming Systems Engineering through Model-Centric Engineering

    Science.gov (United States)

    2018-02-28

    Department of Defense stakeholders . This report covers research performed against the RT-157 objectives, and at the request of our sponsor has expanded to...Technical Report We have also produced models, demonstrations, videos, examples and assembled tools for an Integrated Modeling Environment (IME) for the...information and its use will be provided in future technical reports . 54 Figure 21. Integrating and Interoperability Framework (IoIF) 55

  5. Towards artificial intelligence based diesel engine performance control under varying operating conditions using support vector regression

    Directory of Open Access Journals (Sweden)

    Naradasu Kumar Ravi

    2013-01-01

    Full Text Available Diesel engine designers are constantly on the look-out for performance enhancement through efficient control of operating parameters. In this paper, the concept of an intelligent engine control system is proposed that seeks to ensure optimized performance under varying operating conditions. The concept is based on arriving at the optimum engine operating parameters to ensure the desired output in terms of efficiency. In addition, a Support Vector Machines based prediction model has been developed to predict the engine performance under varying operating conditions. Experiments were carried out at varying loads, compression ratios and amounts of exhaust gas recirculation using a variable compression ratio diesel engine for data acquisition. It was observed that the SVM model was able to predict the engine performance accurately.

  6. Sensor fault diagnosis of aero-engine based on divided flight status

    Science.gov (United States)

    Zhao, Zhen; Zhang, Jun; Sun, Yigang; Liu, Zhexu

    2017-11-01

    Fault diagnosis and safety analysis of an aero-engine have attracted more and more attention in modern society, whose safety directly affects the flight safety of an aircraft. In this paper, the problem concerning sensor fault diagnosis is investigated for an aero-engine during the whole flight process. Considering that the aero-engine is always working in different status through the whole flight process, a flight status division-based sensor fault diagnosis method is presented to improve fault diagnosis precision for the aero-engine. First, aero-engine status is partitioned according to normal sensor data during the whole flight process through the clustering algorithm. Based on that, a diagnosis model is built for each status using the principal component analysis algorithm. Finally, the sensors are monitored using the built diagnosis models by identifying the aero-engine status. The simulation result illustrates the effectiveness of the proposed method.

  7. Validation of a zero-dimensional model for prediction of NOx and engine performance for electronically controlled marine two-stroke diesel engines

    DEFF Research Database (Denmark)

    Scappin, Fabio; Stefansson, Sigurður H.; Haglind, Fredrik

    2012-01-01

    The aim of this paper is to derive a methodology suitable for energy system analysis for predicting the performance and NOx emissions of marine low speed diesel engines. The paper describes a zero-dimensional model, evaluating the engine performance by means of an energy balance and a two zone...... experimental data from two MAN B&W engines; one case being data subject to engine parameter changes corresponding to simulating an electronically controlled engine; the second case providing data covering almost all model input and output parameters. The first case of validation suggests that the model can...... predict specific fuel oil consumption and NOx emissions within the 95% confidence intervals given by the experimental measurements. The second validation confirms the capability of the model to match measured engine output parameters based on measured engine input parameters with a maximum 5% deviation....

  8. Constructing an Efficient Self-Tuning Aircraft Engine Model for Control and Health Management Applications

    Science.gov (United States)

    Armstrong, Jeffrey B.; Simon, Donald L.

    2012-01-01

    Self-tuning aircraft engine models can be applied for control and health management applications. The self-tuning feature of these models minimizes the mismatch between any given engine and the underlying engineering model describing an engine family. This paper provides details of the construction of a self-tuning engine model centered on a piecewise linear Kalman filter design. Starting from a nonlinear transient aerothermal model, a piecewise linear representation is first extracted. The linearization procedure creates a database of trim vectors and state-space matrices that are subsequently scheduled for interpolation based on engine operating point. A series of steady-state Kalman gains can next be constructed from a reduced-order form of the piecewise linear model. Reduction of the piecewise linear model to an observable dimension with respect to available sensed engine measurements can be achieved using either a subset or an optimal linear combination of "health" parameters, which describe engine performance. The resulting piecewise linear Kalman filter is then implemented for faster-than-real-time processing of sensed engine measurements, generating outputs appropriate for trending engine performance, estimating both measured and unmeasured parameters for control purposes, and performing on-board gas-path fault diagnostics. Computational efficiency is achieved by designing multidimensional interpolation algorithms that exploit the shared scheduling of multiple trim vectors and system matrices. An example application illustrates the accuracy of a self-tuning piecewise linear Kalman filter model when applied to a nonlinear turbofan engine simulation. Additional discussions focus on the issue of transient response accuracy and the advantages of a piecewise linear Kalman filter in the context of validation and verification. The techniques described provide a framework for constructing efficient self-tuning aircraft engine models from complex nonlinear

  9. The Application of Problem-Based Learning in Mechanical Engineering

    Science.gov (United States)

    Putra, Z. A.; Dewi, M.

    2018-02-01

    The course of Technology and Material Testing prepare students with the ability to do a variety of material testing in the study of mechanical engineering. Students find it difficult to understand the materials to make them unable to carry out the material testing in accordance with the purpose of study. This happens because they knowledge is not adequately supported by the competence to find and construct learning experience. In this study, quasy experiment research method with pre-post-test with control group design was used. The subjects of the study were students divided in two groups; control and experiment with twenty-two students in each group. Study result: their grades showed no difference in between the pre-test or post-test in control group, but the difference in grade existed between the pre-test and post-test in experiment group. Yet, there is no significant difference in the study result on both groups. The researcher recommend that it is necessary to develop Problem-Based Learning that suits need analysis on D3 Program for Mechanical Engineering Department at the State University of Padang, to ensure the compatibility between Model of Study and problems and need. This study aims to analyze how Problem-Based Learning effects on the course of Technology and Material Testing for the students of D3 Program of Mechanical Engineering of the State University of Padang.

  10. A concise wall temperature model for DI Diesel engines

    Energy Technology Data Exchange (ETDEWEB)

    Torregrosa, A.; Olmeda, P.; Degraeuwe, B. [CMT-Motores Termicos, Universidad Politecnica de Valencia (Spain); Reyes, M. [Centro de Mecanica de Fluidos y Aplicaciones, Universidad Simon Bolivar (Venezuela)

    2006-08-15

    A concise resistor model for wall temperature prediction in diesel engines with piston cooling is presented here. The model uses the instantaneous in-cylinder pressure and some usually measured operational parameters to predict the temperature of the structural elements of the engine. The resistor model was adjusted by means of temperature measurements in the cylinder head, the liner and the piston. For each model parameter, an expression as a function of the engine geometry, operational parameters and material properties was derived to make the model applicable to other similar engines. The model predicts well the cylinder head, liner and piston temperature and is sensitive to variations of operational parameters such as the start of injection, coolant and oil temperature and engine speed and load. (author)

  11. Genetic-evolution-based optimization methods for engineering design

    Science.gov (United States)

    Rao, S. S.; Pan, T. S.; Dhingra, A. K.; Venkayya, V. B.; Kumar, V.

    1990-01-01

    This paper presents the applicability of a biological model, based on genetic evolution, for engineering design optimization. Algorithms embodying the ideas of reproduction, crossover, and mutation are developed and applied to solve different types of structural optimization problems. Both continuous and discrete variable optimization problems are solved. A two-bay truss for maximum fundamental frequency is considered to demonstrate the continuous variable case. The selection of locations of actuators in an actively controlled structure, for minimum energy dissipation, is considered to illustrate the discrete variable case.

  12. Modeling Engineered Nanomaterials (ENMs) Fate and ...

    Science.gov (United States)

    Under the Toxic Substances Control Act (TSCA), the Environmental Protection Agency (EPA) is required to perform new chemical reviews of engineered nanomaterials (ENMs) identified in pre-manufacture notices. However, environmental fate models developed for traditional contaminants are limited in their ability to simulate the environmental behavior of nanomaterials due to incomplete understanding and representation of the processes governing nanomaterial distribution in the environment and by scarce empirical data quantifying the interaction of nanomaterials with environmental surfaces. We have updated the Water Quality Analysis Simulation Program (WASP), version S, to incorporate nanomaterials as an explicitly simulated state variable. WASPS now has the capability to simulate nanomaterial fate and transport in surface waters and sediments using heteroaggregation, the kinetic process governing the attachment of nanomaterials to particles and subsequently ENM distribution in the aqueous and sediment phases. Unlike dissolved chemicals which use equilibrium partition coefficients, heteroaggregation consists of a particle collision rate and an attachment efficiency ( lXhet) that generally acts as a one direction process. To demonstrate, we used a derived a het value from sediment attachment studies to parameterize WASP for simulation of multi walled carbon nanotube (MWCNT) transport in Brier Creek, a coastal plain river located in central eastern Georgia, USA and a tr

  13. Modelling and Inverse-Modelling: Experiences with O.D.E. Linear Systems in Engineering Courses

    Science.gov (United States)

    Martinez-Luaces, Victor

    2009-01-01

    In engineering careers courses, differential equations are widely used to solve problems concerned with modelling. In particular, ordinary differential equations (O.D.E.) linear systems appear regularly in Chemical Engineering, Food Technology Engineering and Environmental Engineering courses, due to the usefulness in modelling chemical kinetics,…

  14. Model-based neural networks to predict emissions in a diesel engine operating with biodiesel blends of castor; Modelo basado en redes neuronales para predecir las emisiones en un motor diésel que opera con mezclas de biodiésel de higuerilla

    Directory of Open Access Journals (Sweden)

    Fabio Narváez

    2012-12-01

    Full Text Available Some identification methods of nonlinear systems using artificialneural networks are explained. Also, a model based on Neural Networks“Supervised Feed Forward” is presented, developed to identifyand predict the behavior of volumetric emissions from combustion of astationary diésel engine based on two input variables: the engine load and the mixture of castor biodiésel. The neural network training and model validation was performed by using the NNModel.

  15. The role of technology and engineering models in transforming healthcare.

    Science.gov (United States)

    Pavel, Misha; Jimison, Holly Brugge; Wactlar, Howard D; Hayes, Tamara L; Barkis, Will; Skapik, Julia; Kaye, Jeffrey

    2013-01-01

    The healthcare system is in crisis due to challenges including escalating costs, the inconsistent provision of care, an aging population, and high burden of chronic disease related to health behaviors. Mitigating this crisis will require a major transformation of healthcare to be proactive, preventive, patient-centered, and evidence-based with a focus on improving quality-of-life. Information technology, networking, and biomedical engineering are likely to be essential in making this transformation possible with the help of advances, such as sensor technology, mobile computing, machine learning, etc. This paper has three themes: 1) motivation for a transformation of healthcare; 2) description of how information technology and engineering can support this transformation with the help of computational models; and 3) a technical overview of several research areas that illustrate the need for mathematical modeling approaches, ranging from sparse sampling to behavioral phenotyping and early detection. A key tenet of this paper concerns complementing prior work on patient-specific modeling and simulation by modeling neuropsychological, behavioral, and social phenomena. The resulting models, in combination with frequent or continuous measurements, are likely to be key components of health interventions to enhance health and wellbeing and the provision of healthcare.

  16. Modelling and Simulation of Gas Engines Using Aspen HYSYS

    Directory of Open Access Journals (Sweden)

    M. C. Ekwonu

    2013-12-01

    Full Text Available In this paper gas engine model was developed in Aspen HYSYS V7.3 and validated with Waukesha 16V275GL+ gas engine. Fuel flexibility, fuel types and part load performance of the gas engine were investigated. The design variability revealed that the gas engine can operate on poor fuel with low lower heating value (LHV such as landfill gas, sewage gas and biogas with biogas offering potential integration with bottoming cycles when compared to natural gas. The result of the gas engine simulation gave an efficiency 40.7% and power output of 3592kW.

  17. Two Models of Engineering Education for the Professional Practice

    NARCIS (Netherlands)

    Ir. Dick van Schenk Brill; Ir Peter Boots; Ir. Peter van Kollenburg

    2002-01-01

    Two models for engineering education that may answer the needs for "Renaissance Engineers" are described in this paper. They were the outcome of an educational renewal project, funded by the Dutch Ministry of Education and industrial companies. The first model (Corporate Curriculum) aims to bring

  18. Support of Modelling in Process-Engineering Education

    NARCIS (Netherlands)

    Schaaf, van der H.; Vermuë, M.H.; Tramper, J.; Hartog, R.J.M.

    2006-01-01

    An objective of the Process Technology curriculum at Wageningen University is to teach students a stepwise modeling approach in the context of process engineering. Many process-engineering students have difficulty with learning to design a model. Some common problems are lack of structure in the

  19. Engineering teacher training models and experiences

    Science.gov (United States)

    González-Tirados, R. M.

    2009-04-01

    Education Area, we renewed the programme, content and methodology, teaching the course under the name of "Initial Teacher Training Course within the framework of the European Higher Education Area". Continuous Training means learning throughout one's life as an Engineering teacher. They are actions designed to update and improve teaching staff, and are systematically offered on the current issues of: Teaching Strategies, training for research, training for personal development, classroom innovations, etc. They are activities aimed at conceptual change, changing the way of teaching and bringing teaching staff up-to-date. At the same time, the Institution is at the disposal of all teaching staff as a meeting point to discuss issues in common, attend conferences, department meetings, etc. In this Congress we present a justification of both training models and their design together with some results obtained on: training needs, participation, how it is developing and to what extent students are profiting from it.

  20. Human performance models for computer-aided engineering

    Science.gov (United States)

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

    1989-01-01

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

  1. Adaptive Hardware Cryptography Engine Based on FPGA

    International Nuclear Information System (INIS)

    Afify, M.A.A.

    2011-01-01

    In the last two decades, with spread of the real time applications over public networks or communications the need for information security become more important but with very high speed for data processing, to keep up with the real time applications requirements, that is the reason for using FPGA as an implementation platform for the proposed cryptography engine. Hence in this thesis a new S-Box design has been demonstrated and implemented, there is a comparison for the simulation results for proposed S-Box simulation results with respect to different designs for S-Box in DES, Two fish and Rijndael algorithms and another comparison among proposed S-Box with different sizes. The proposed S-Box implemented with 32-bits Input data lines and compared with different designs in the encryption algorithms with the same input lines, the proposed S-Box gives implementation results for the maximum frequency 120 MHz but the DES S-Box gives 34 MHz and Rijndael gives 71 MHz, on the other hand the proposed design gives the best implementation area, hence it gives 50 Configurable logic Block CLB but DES gives 88 CLB. The proposed S-Box implemented in different sizes 64-bits, 128-bits, and 256-bits for input data lines. The implementation carried out by using UniDAq PCI card with FPGA Chip XCV 800, synthesizing carried out for all designs by using Leonardo spectrum and simulation carried out by using model sim simulator program form the FPGA advantage package. Finally the results evaluation and verifications carried out using the UniDAq FPGA PCI card with chip XCV 800. Different cases study have been implemented, data encryption, images encryption, voice encryption, and video encryption. A prototype for Remote Monitoring Control System has been implemented. Finally the proposed design for S-Box has a significant achievement in maximum frequency, implementation area, and encryption strength.

  2. Three-Dimensional Analysis and Modeling of a Wankel Engine

    Science.gov (United States)

    Raju, M. S.; Willis, E. A.

    1991-01-01

    A new computer code, AGNI-3D, has been developed for the modeling of combustion, spray, and flow properties in a stratified-charge rotary engine (SCRE). The mathematical and numerical details of the new code are described by the first author in a separate NASA publication. The solution procedure is based on an Eulerian-Lagrangian approach where the unsteady, three-dimensional Navier-Stokes equations for a perfect gas-mixture with variable properties are solved in generalized, Eulerian coordinates on a moving grid by making use of an implicit finite-volume, Steger-Warming flux vector splitting scheme. The liquid-phase equations are solved in Lagrangian coordinates. The engine configuration studied was similar to existing rotary engine flow-visualization and hot-firing test rigs. The results of limited test cases indicate a good degree of qualitative agreement between the predicted and measured pressures. It is conjectured that the impulsive nature of the torque generated by the observed pressure nonuniformity may be one of the mechanisms responsible for the excessive wear of the timing gears observed during the early stages of the rotary combustion engine (RCE) development. It was identified that the turbulence intensities near top-dead-center were dominated by the compression process and only slightly influenced by the intake and exhaust processes. Slow mixing resulting from small turbulence intensities within the rotor pocket and also from a lack of formation of any significant recirculation regions within the rotor pocket were identified as the major factors leading to incomplete combustion. Detailed flowfield results during exhaust and intake, fuel injection, fuel vaporization, combustion, mixing and expansion processes are also presented. The numerical procedure is very efficient as it takes 7 to 10 CPU hours on a CRAY Y-MP for one entire engine cycle when the computations are performed over a 31 x16 x 20 grid.

  3. Study on Fault Diagnostics of a Turboprop Engine Using Inverse Performance Model and Artificial Intelligent Methods

    Science.gov (United States)

    Kong, Changduk; Lim, Semyeong

    2011-12-01

    Recently, the health monitoring system of major gas path components of gas turbine uses mostly the model based method like the Gas Path Analysis (GPA). This method is to find quantity changes of component performance characteristic parameters such as isentropic efficiency and mass flow parameter by comparing between measured engine performance parameters such as temperatures, pressures, rotational speeds, fuel consumption, etc. and clean engine performance parameters without any engine faults which are calculated by the base engine performance model. Currently, the expert engine diagnostic systems using the artificial intelligent methods such as Neural Networks (NNs), Fuzzy Logic and Genetic Algorithms (GAs) have been studied to improve the model based method. Among them the NNs are mostly used to the engine fault diagnostic system due to its good learning performance, but it has a drawback due to low accuracy and long learning time to build learning data base if there are large amount of learning data. In addition, it has a very complex structure for finding effectively single type faults or multiple type faults of gas path components. This work builds inversely a base performance model of a turboprop engine to be used for a high altitude operation UAV using measured performance data, and proposes a fault diagnostic system using the base engine performance model and the artificial intelligent methods such as Fuzzy logic and Neural Network. The proposed diagnostic system isolates firstly the faulted components using Fuzzy Logic, then quantifies faults of the identified components using the NN leaned by fault learning data base, which are obtained from the developed base performance model. In leaning the NN, the Feed Forward Back Propagation (FFBP) method is used. Finally, it is verified through several test examples that the component faults implanted arbitrarily in the engine are well isolated and quantified by the proposed diagnostic system.

  4. The use of mathematical models in teaching wastewater treatment engineering

    DEFF Research Database (Denmark)

    Morgenroth, Eberhard Friedrich; Arvin, Erik; Vanrolleghem, P.

    2002-01-01

    Mathematical modeling of wastewater treatment processes has become increasingly popular in recent years. To prepare students for their future careers, environmental engineering education should provide students with sufficient background and experiences to understand and apply mathematical models...

  5. Using cognitive modeling for requirements engineering in anesthesiology

    NARCIS (Netherlands)

    Pott, C; le Feber, J

    2005-01-01

    Cognitive modeling is a complexity reducing method to describe significant cognitive processes under a specified research focus. Here, a cognitive process model for decision making in anesthesiology is presented and applied in requirements engineering. Three decision making situations of

  6. Enhanced Fan Noise Modeling for Turbofan Engines

    Science.gov (United States)

    Krejsa, Eugene A.; Stone, James R.

    2014-01-01

    This report describes work by consultants to Diversitech Inc. for the NASA Glenn Research Center (GRC) to revise the fan noise prediction procedure based on fan noise data obtained in the 9- by 15 Foot Low-Speed Wind Tunnel at GRC. The purpose of this task is to begin development of an enhanced, analytical, more physics-based, fan noise prediction method applicable to commercial turbofan propulsion systems. The method is to be suitable for programming into a computational model for eventual incorporation into NASA's current aircraft system noise prediction computer codes. The scope of this task is in alignment with the mission of the Propulsion 21 research effort conducted by the coalition of NASA, state government, industry, and academia to develop aeropropulsion technologies. A model for fan noise prediction was developed based on measured noise levels for the R4 rotor with several outlet guide vane variations and three fan exhaust areas. The model predicts the complete fan noise spectrum, including broadband noise, tones, and for supersonic tip speeds, combination tones. Both spectra and directivity are predicted. Good agreement with data was achieved for all fan geometries. Comparisons with data from a second fan, the ADP fan, also showed good agreement.

  7. Property-Based Software Engineering Measurement

    Science.gov (United States)

    Briand, Lionel C.; Morasca, Sandro; Basili, Victor R.

    1997-01-01

    Little theory exists in the field of software system measurement. Concepts such as complexity, coupling, cohesion or even size are very often subject to interpretation and appear to have inconsistent definitions in the literature. As a consequence, there is little guidance provided to the analyst attempting to define proper measures for specific problems. Many controversies in the literature are simply misunderstandings and stem from the fact that some people talk about different measurement concepts under the same label (complexity is the most common case). There is a need to define unambiguously the most important measurement concepts used in the measurement of software products. One way of doing so is to define precisely what mathematical properties characterize these concepts, regardless of the specific software artifacts to which these concepts are applied. Such a mathematical framework could generate a consensus in the software engineering community and provide a means for better communication among researchers, better guidelines for analysts, and better evaluation methods for commercial static analyzers for practitioners. In this paper, we propose a mathematical framework which is generic, because it is not specific to any particular software artifact and rigorous, because it is based on precise mathematical concepts. We use this framework to propose definitions of several important measurement concepts (size, length, complexity, cohesion, coupling). It does not intend to be complete or fully objective; other frameworks could have been proposed and different choices could have been made. However, we believe that the formalisms and properties we introduce are convenient and intuitive. This framework contributes constructively to a firmer theoretical ground of software measurement.

  8. A Model for Implementing Practical Design in the Education of Mechanical Engineers

    DEFF Research Database (Denmark)

    Hansen, Michael Rygaard; Mouritsen, Ole Ø.; Andersen, Torben Ole

    2006-01-01

    In this paper the PBL model used at Aalborg University in the mechanical engineering is shortly presented. A specific semester with a both theoretical and practical content that allow the students to is presented in detail. It is then used as a reference project for a subsequent discussion on three...... potential concerns with respect to the continued succes of problem and project based learning in mechanical and mechatronics engineering namely: individual assessment, bologna (student exchange) model and research based teaching....

  9. An algebraic approach to modeling in software engineering

    International Nuclear Information System (INIS)

    Loegel, C.J.; Ravishankar, C.V.

    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

  10. Mean Value SI Engine Model for Control Studies

    DEFF Research Database (Denmark)

    Hendricks, Elbert; Sorenson, Spencer C

    1990-01-01

    This paper presents a mathematically simple nonlinear three state (three differential equation) dynamic model of an SI engine which has the same steady state accuracy as a typical dynamometer measurement of the engine over its entire speed/load operating range (± 2.0%). The model's accuracy for l....... The model can easily be run on a Personal Computer (PC) using a ordinary differential equation (ODE) integrating routine or package. This makes the model is useful for control system design and evaluation....

  11. Computational fluid dynamics modeling in yarn engineering

    CSIR Research Space (South Africa)

    Patanaik, A

    2011-07-01

    Full Text Available pattern in the nozzles plays a significant role in the reduction of hairiness. CFD has been effectively utilized in yarn engineering to understand the actual mechanism of reducing yarn hairiness. The influence of different nozzle parameters...

  12. Mechanical properties of Composite Engineering Structures by Multivolume Micromechanical Modelling

    Directory of Open Access Journals (Sweden)

    B. Novotný

    2000-01-01

    Full Text Available Engineering structures often consist of elements having the character of a periodically repeated composite structure. A multivolume micromechanical model based on a representative cell division into r1 × r2 × r3 subcells with different elastic material properties has been used in this paper to derive macromechanical characteristics of the composite construction response to applied load and temperature changes. The multivolume method is based on ensuring the equilibrium of the considered volume on an average basis. In the same (average way, the continuity conditions of displacements and tractions at the interfaces between subcells and between neighboring representative elements are imposed, resulting in a homogenization procedure that eliminates the discrete nature of the composite model. The details of the method are shown for the case of a concrete block pavement. A parametric study is presented illustrating the influence of joint thickness, joint filling material properties and the quality of bonding between block and filler elements.

  13. Subsidence characterization and modeling for engineered facilities in Arizona, USA

    Directory of Open Access Journals (Sweden)

    M. L. Rucker

    2015-11-01

    Full Text Available Several engineered facilities located on deep alluvial basins in southern Arizona, including flood retention structures (FRS and a coal ash disposal facility, have been impacted by up to as much as 1.8 m of differential land subsidence and associated earth fissuring. Compressible basin alluvium depths are as deep as about 300 m, and historic groundwater level declines due to pumping range from 60 to more than 100 m at these facilities. Addressing earth fissure-inducing ground strain has required alluvium modulus characterization to support finite element modeling. The authors have developed Percolation Theory-based methodologies to use effective stress and generalized geo-material types to estimate alluvium modulus as a function of alluvium lithology, depth and groundwater level. Alluvial material modulus behavior may be characterized as high modulus gravel-dominated, low modulus sand-dominated, or very low modulus fines-dominated (silts and clays alluvium. Applied at specific aquifer stress points, such as significant pumping wells, this parameter characterization and quantification facilitates subsidence magnitude modeling at its' sources. Modeled subsidence is then propagated over time across the basin from the source(s using a time delay exponential decay function similar to the soil mechanics consolidation coefficient, only applied laterally. This approach has expanded subsidence modeling capabilities on scales of engineered facilities of less than 2 to more than 15 km.

  14. Engine control system having fuel-based adjustment

    Science.gov (United States)

    Willi, Martin L [Dunlap, IL; Fiveland, Scott B [Metamora, IL; Montgomery, David T [Edelstein, IL; Gong, Weidong [Dunlap, IL

    2011-03-15

    A control system for an engine having a cylinder is disclosed having an engine valve configured to affect a fluid flow of the cylinder, an actuator configured to move the engine valve, and an in-cylinder sensor configured to generate a signal indicative of a characteristic of fuel entering the cylinder. The control system also has a controller in communication with the actuator and the sensor. The controller is configured to determine the characteristic of the fuel based on the signal and selectively regulate the actuator to adjust a timing of the engine valve based on the characteristic of the fuel.

  15. Performance Analysis of the Vehicle Diesel Engine-ORC Combined System Based on a Screw Expander

    Directory of Open Access Journals (Sweden)

    Kai Yang

    2014-05-01

    Full Text Available To achieve energy saving and emission reduction for vehicle diesel engines, the organic Rankine cycle (ORC was employed to recover waste heat from vehicle diesel engines, R245fa was used as ORC working fluid, and the resulting vehicle diesel engine-ORC combined system was presented. The variation law of engine exhaust energy rate under various operating conditions was obtained, and the running performances of the screw expander were introduced. Based on thermodynamic models and theoretical calculations, the running performance of the vehicle diesel engine-ORC combined system was analyzed under various engine operating condition scenarios. Four evaluation indexes were defined: engine thermal efficiency increasing ratio (ETEIR, waste heat recovery efficiency (WHRE, brake specific fuel consumption (BSFC of the combined system, and improvement ratio of BSFC (IRBSFC. Results showed that when the diesel engine speed is 2200 r/min and diesel engine torque is 1200 N·m, the power output of the combined system reaches its maximum of approximately 308.6 kW, which is 28.6 kW higher than that of the diesel engine. ETEIR, WHRE, and IRBSFC all reach their maxima at 10.25%, 9.90%, and 9.30%, respectively. Compared with that of the diesel engine, the BSFC of the combined system is obviously improved under various engine operating conditions.

  16. Comparing in Cylinder Pressure Modelling of a DI Diesel Engine Fuelled on Alternative Fuel Using Two Tabulated Chemistry Approaches.

    Science.gov (United States)

    Ngayihi Abbe, Claude Valery; Nzengwa, Robert; Danwe, Raidandi

    2014-01-01

    The present work presents the comparative simulation of a diesel engine fuelled on diesel fuel and biodiesel fuel. Two models, based on tabulated chemistry, were implemented for the simulation purpose and results were compared with experimental data obtained from a single cylinder diesel engine. The first model is a single zone model based on the Krieger and Bormann combustion model while the second model is a two-zone model based on Olikara and Bormann combustion model. It was shown that both models can predict well the engine's in-cylinder pressure as well as its overall performances. The second model showed a better accuracy than the first, while the first model was easier to implement and faster to compute. It was found that the first method was better suited for real time engine control and monitoring while the second one was better suited for engine design and emission prediction.

  17. LOGISTICS RISK RESEARCH OF PREFABRICATED HOUSE CONSTRUCTION ENGINEERING BASED ON CREDIBILITY METHOD

    Directory of Open Access Journals (Sweden)

    Xiaoping Bai

    2017-07-01

    Full Text Available In recent years, the prefabricated house industry has rapid development,.Because of fewer suppliers, higher demand transport scheme and complex quality test, the risks of construction engineering logistics links are relatively high. Studying how to effectively evaluate the risks of construction engineering logistics links is significant. According to the characteristics of the prefabricated house construction engineering, we analyse the construction engineering logistics risks and use the combined weights method to determine the weight of indexes which contains both subjective and objective factors, to improve the scientific value and the validity of the assessment. Based on credibility measure method, a new logistics risk evaluation model in prefabricated housing is established to estimate the risk during making prefabricated house construction engineering. The presented model can avoid the subjectivity of selecting the membership function and solve the problem of how to comprehensively assess the construction engineering logistics risk in a certain extent.

  18. Process-based Cost Estimation for Ramjet/Scramjet Engines

    Science.gov (United States)

    Singh, Brijendra; Torres, Felix; Nesman, Miles; Reynolds, John

    2003-01-01

    Process-based cost estimation plays a key role in effecting cultural change that integrates distributed science, technology and engineering teams to rapidly create innovative and affordable products. Working together, NASA Glenn Research Center and Boeing Canoga Park have developed a methodology of process-based cost estimation bridging the methodologies of high-level parametric models and detailed bottoms-up estimation. The NASA GRC/Boeing CP process-based cost model provides a probabilistic structure of layered cost drivers. High-level inputs characterize mission requirements, system performance, and relevant economic factors. Design alternatives are extracted from a standard, product-specific work breakdown structure to pre-load lower-level cost driver inputs and generate the cost-risk analysis. As product design progresses and matures the lower level more detailed cost drivers can be re-accessed and the projected variation of input values narrowed, thereby generating a progressively more accurate estimate of cost-risk. Incorporated into the process-based cost model are techniques for decision analysis, specifically, the analytic hierarchy process (AHP) and functional utility analysis. Design alternatives may then be evaluated not just on cost-risk, but also user defined performance and schedule criteria. This implementation of full-trade study support contributes significantly to the realization of the integrated development environment. The process-based cost estimation model generates development and manufacturing cost estimates. The development team plans to expand the manufacturing process base from approximately 80 manufacturing processes to over 250 processes. Operation and support cost modeling is also envisioned. Process-based estimation considers the materials, resources, and processes in establishing cost-risk and rather depending on weight as an input, actually estimates weight along with cost and schedule.

  19. An Engineering Approach to Atomic Transaction Verification : Use of a Simple Object Model to Achieve Semantics-based Reasoning at Compile-time

    NARCIS (Netherlands)

    Spelt, D.; Even, S.J.

    In this paper, we take an engineering approach to atomic transaction verification. We discuss the design and implementation of a verification tool that can reason about the semantics of atomic database operations. To bridge the gap between language design and automated reasoning, we make use of a

  20. Validation of a zero-dimensional model for prediction of NOx and engine performance for electronically controlled marine two-stroke diesel engines

    International Nuclear Information System (INIS)

    Scappin, Fabio; Stefansson, Sigurður H.; Haglind, Fredrik; Andreasen, Anders; Larsen, Ulrik

    2012-01-01

    The aim of this paper is to derive a methodology suitable for energy system analysis for predicting the performance and NO x emissions of marine low speed diesel engines. The paper describes a zero-dimensional model, evaluating the engine performance by means of an energy balance and a two zone combustion model using ideal gas law equations over a complete crank cycle. The combustion process is divided into intervals, and the product composition and flame temperature are calculated in each interval. The NO x emissions are predicted using the extended Zeldovich mechanism. The model is validated using experimental data from two MAN B and W engines; one case being data subject to engine parameter changes corresponding to simulating an electronically controlled engine; the second case providing data covering almost all model input and output parameters. The first case of validation suggests that the model can predict specific fuel oil consumption and NO x emissions within the 95% confidence intervals given by the experimental measurements. The second validation confirms the capability of the model to match measured engine output parameters based on measured engine input parameters with a maximum 5% deviation. - Highlights: ► A fast realistic model of a marine two-stroke low speed diesel engine was derived. ► The model is fast and accurate enough for future complex energy systems analysis. ► The effects of engine tuning were validated with experimental tests. ► The model was validated while constrained by experimental input and output data.

  1. Coastal flood protection by a combined nature-based and engineering approach: Modeling the effects of marsh geometry and surrounding dikes

    Science.gov (United States)

    Stark, Jeroen; Plancke, Yves; Ides, Stefaan; Meire, Patrick; Temmerman, Stijn

    2016-06-01

    As ecosystem-based adaptation to global change is gaining ground, strategies to protect coastal and estuarine areas from increasing flood hazards are starting to consist of natural tidal wetland conservation and restoration in addition to conventional coastal defense structures. In this study, the capacity of tidal wetlands to locally attenuate peak water levels during storm tides is analyzed using a two-dimensional hydrodynamic model (TELEMAC2D) for a 3000 ha intertidal marsh (SW Netherlands). Model results indicate that peak water level reduction largely varies between individual flooding events and between different locations in the marsh. Model scenarios with variable dike positions show that attenuation rates can be minimized by blockage and set up of water levels against dikes or other structures confining the marsh size. This blockage only affects peak water level attenuation across wetlands if the duration of the flood wave is long compared to the marsh size. A minimum marsh width of 6-10 km is required to completely avoid blockage effects for the storm tidal cases assessed in this study. If blockage does not affect flood wave propagation, variations in attenuation rates between different locations in the marsh and between tides with varying high water levels can be explained with a single relationship based on the ratio between the water volume on the marsh platform and the total water volume on the platform and in the channels. Attenuation starts to occur when this ratio exceeds 0.2-0.4 and increases from there on up to a maximum of 29 cm/km for a ratio of about 0.85. Furthermore, model scenarios with varying marsh channel depth show that marsh scale attenuation rates increase by up to 4 cm/km if the channel elevation is raised by 0.7 m on average. Conversely, marsh scale attenuation rates decrease by up to 2 cm/km for scenarios in which the channels are lowered by 0.9 m on average. The marsh platform elevation has little effect on the maximum attenuation

  2. Project Based Learning Activities in Engineering Education

    Directory of Open Access Journals (Sweden)

    Tiago Faustino Andrade

    2013-03-01

    Full Text Available In the present work, the author reports examples of his involvement in different teaching/learning methodologies during his five years of the Integrated Master Degree in Mechanical Engineering at the Faculty of Engineering of University of Porto. The aim is to explain how useful those experiences have been, allowing him to explore many techno-scientific activities within his engineering education while student as well as other transferable skills and later, up to the present, as a professional in academic environment. The author wishes to underline the excellent opportunity he had to practice reflection processes as an essential methodology of his engineering education.

  3. Underwater striling engine design with modified one-dimensional model

    Science.gov (United States)

    Li, Daijin; Qin, Kan; Luo, Kai

    2015-09-01

    Stirling engines are regarded as an efficient and promising power system for underwater devices. Currently, many researches on one-dimensional model is used to evaluate thermodynamic performance of Stirling engine, but in which there are still some aspects which cannot be modeled with proper mathematical models such as mechanical loss or auxiliary power. In this paper, a four-cylinder double-acting Stirling engine for Unmanned Underwater Vehicles (UUVs) is discussed. And a one-dimensional model incorporated with empirical equations of mechanical loss and auxiliary power obtained from experiments is derived while referring to the Stirling engine computer model of National Aeronautics and Space Administration (NASA). The P-40 Stirling engine with sufficient testing results from NASA is utilized to validate the accuracy of this one-dimensional model. It shows that the maximum error of output power of theoretical analysis results is less than 18% over testing results, and the maximum error of input power is no more than 9%. Finally, a Stirling engine for UUVs is designed with Schmidt analysis method and the modified one-dimensional model, and the results indicate this designed engine is capable of showing desired output power.

  4. Underwater striling engine design with modified one-dimensional model

    Directory of Open Access Journals (Sweden)

    Daijin Li

    2015-05-01

    Full Text Available Stirling engines are regarded as an efficient and promising power system for underwater devices. Currently, many researches on one-dimensional model is used to evaluate thermodynamic performance of Stirling engine, but in which there are still some aspects which cannot be modeled with proper mathematical models such as mechanical loss or auxiliary power. In this paper, a four-cylinder double-acting Stirling engine for Unmanned Underwater Vehicles (UUVs is discussed. And a one-dimensional model incorporated with empirical equations of mechanical loss and auxiliary power obtained from experiments is derived while referring to the Stirling engine computer model of National Aeronautics and Space Administration (NASA. The P-40 Stirling engine with sufficient testing results from NASA is utilized to validate the accuracy of this one-dimensional model. It shows that the maximum error of output power of theoretical analysis results is less than 18% over testing results, and the maximum error of input power is no more than 9%. Finally, a Stirling engine for UUVs is designed with Schmidt analysis method and the modified one-dimensional model, and the results indicate this designed engine is capable of showing desired output power.

  5. The use of mathematical models in teaching wastewater treatment engineering

    DEFF Research Database (Denmark)

    Morgenroth, Eberhard Friedrich; Arvin, Erik; Vanrolleghem, P.

    2002-01-01

    Mathematical modeling of wastewater treatment processes has become increasingly popular in recent years. To prepare students for their future careers, environmental engineering education should provide students with sufficient background and experiences to understand and apply mathematical models...... efficiently and responsibly. Approaches for introducing mathematical modeling into courses on wastewater treatment engineering are discussed depending on the learning objectives, level of the course and the time available....

  6. Development Testing of 1-Newton ADN-Based Rocket Engines

    Science.gov (United States)

    Anflo, K.; Gronland, T.-A.; Bergman, G.; Nedar, R.; Thormählen, P.

    2004-10-01

    With the objective to reduce operational hazards and improve specific and density impulse as compared with hydrazine, the Research and Development (R&D) of a new monopropellant for space applications based on AmmoniumDiNitramide (ADN), was first proposed in 1997. This pioneering work has been described in previous papers1,2,3,4 . From the discussion above, it is clear that cost savings as well as risk reduction are the main drivers to develop a new generation of reduced hazard propellants. However, this alone is not enough to convince a spacecraft builder to choose a new technology. Cost, risk and schedule reduction are good incentives, but a spacecraft supplier will ask for evidence that this new propulsion system meets a number of requirements within the following areas: This paper describes the ongoing effort to develop a storable liquid monopropellant blend, based on AND, and its specific rocket engines. After building and testing more than 20 experimental rocket engines, the first Engineering Model (EM-1) has now accumulated more than 1 hour of firing-time. The results from test firings have validated the design. Specific impulse, combustion stability, blow-down capability and short pulse capability are amongst the requirements that have been demonstrated. The LMP-103x propellant candidate has been stored for more than 1 year and initial material compatibility screening and testing has started. 1. Performance &life 2. Impact on spacecraft design &operation 3. Flight heritage Hereafter, the essential requirements for some of these areas are outlined. These issues are discussed in detail in a previous paper1 . The use of "Commercial Of The Shelf" (COTS) propulsion system components as much as possible is essential to minimize the overall cost, risk and schedule. This leads to the conclusion that the Technology Readiness Level (TRL) 5 has been reached for the thruster and propellant. Furthermore, that the concept of ADN-based propulsion is feasible.

  7. Logistics Systems Engineer – Interdisciplinary Competence Model for Modern Education

    OpenAIRE

    Tarvo Niine; Ott Koppel

    2015-01-01

    Logistics is an interdisciplinary field of study. Modern logisticians need to integrate business management and administration skills with technology design, IT systems and other engineering fields. However, based on research of university curricula and competence standards in logistics, the engineering aspect is not represented to full potential. There are some treatments of logistician competences which relate to engineering, but not a modernized one with wide-spread recognition. This paper...

  8. Journal of Modeling, Design and Management of Engineering ...

    African Journals Online (AJOL)

    The Journal of Modeling, Design & Management of Engineering Systems publishes original research reports, short communications, and critical reviews in any branch of engineering and allied fields ... Adsorption studies on bleaching of palm-kernel oil with activated bentonite clay · EMAIL FULL TEXT EMAIL FULL TEXT

  9. 3D engineered models for highway construction : the Iowa experience.

    Science.gov (United States)

    2015-06-01

    3D engineered modeling is a relatively new and developing technology that can provide numerous bene ts to owners, engineers, : contractors, and the general public. This manual is for highway agencies that are considering or are in the process of s...

  10. Chemical Information in Scirus and BASE (Bielefeld Academic Search Engine)

    Science.gov (United States)

    Bendig, Regina B.

    2009-01-01

    The author sought to determine to what extent the two search engines, Scirus and BASE (Bielefeld Academic Search Engines), would be useful to first-year university students as the first point of searching for chemical information. Five topics were searched and the first ten records of each search result were evaluated with regard to the type of…

  11. Problem-Based Learning in Engineering Ethics Courses

    Science.gov (United States)

    Kirkman, Robert

    2016-01-01

    I describe the first stages of a process of design research in which I employ problem-based learning in a course in engineering ethics, which fulfills a requirement for students in engineering degree programs. The aim of the course is to foster development of particular cognitive skills contributing to moral imagination, a capacity to notice,…

  12. Biodegradable Polymer-Based Scaffolds for Bone Tissue Engineering

    CERN Document Server

    Sultana, Naznin

    2013-01-01

    This book addresses the principles, methods and applications of biodegradable polymer based scaffolds for bone tissue engineering. The general principle of bone tissue engineering is reviewed and the traditional and novel scaffolding materials, their properties and scaffold fabrication techniques are explored. By acting as temporary synthetic extracellular matrices for cell accommodation, proliferation, and differentiation, scaffolds play a pivotal role in tissue engineering. This book does not only provide the comprehensive summary of the current trends in scaffolding design but also presents the new trends and directions for scaffold development for the ever expanding tissue engineering applications.

  13. Engine control system having fuel-based timing

    Science.gov (United States)

    Willi, Martin L [Dunlap, IL; Fiveland, Scott B [Metamora, IL; Montgomery, David T [Edelstein, IL; Gong, Weidong [Dunlap, IL

    2012-04-03

    A control system for an engine having a cylinder is disclosed having an engine valve movable to regulate a fluid flow of the cylinder and an actuator associated with the engine valve. The control system also has a sensor configured to generate a signal indicative of an amount of an air/fuel mixture remaining within the cylinder after completion of a first combustion event and a controller in communication with the actuator and the sensor. The controller may be configured to compare the amount with a desired amount, and to selectively regulate the actuator to adjust a timing of the engine valve associated with a subsequent combustion event based on the comparison.

  14. THERMODYNAMIC MODELLING OF A PISTONS ENGINE ...

    African Journals Online (AJOL)

    2013-06-30

    Jun 30, 2013 ... Simulation is carried out for a gasoline engine, and the results obtained show that: the maximum of NO concentrations corresponds to an equivalent ratio of 0,9. For leaner or richer equivalence ratios, concentration decreased. The. NO concentrations depend of various parameters (spark timing angle, ...

  15. Modeling uncertainty in requirements engineering decision support

    Science.gov (United States)

    Feather, Martin S.; Maynard-Zhang, Pedrito; Kiper, James D.

    2005-01-01

    One inherent characteristic of requrements engineering is a lack of certainty during this early phase of a project. Nevertheless, decisions about requirements must be made in spite of this uncertainty. Here we describe the context in which we are exploring this, and some initial work to support elicitation of uncertain requirements, and to deal with the combination of such information from multiple stakeholders.

  16. A new closed-form thermodynamic model for thermal simulation of spark ignition internal combustion engines

    International Nuclear Information System (INIS)

    Barjaneh, Afshin; Sayyaadi, Hoseyn

    2015-01-01

    Highlights: • A new closed-form thermal model was developed for SI engines. • Various irreversibilities of real engines were integrated into the model. • The accuracy of the model was examined on two real SI engines. • The superiority of the model to previous closed-form models was shown. • Accuracy and losses were studied over the operating range of engines. - Abstract: A closed form model based on finite speed thermodynamics, FST, modified to consider various losses was developed on Otto cycle. In this regard, the governing equations of the finite speed thermodynamics were developed for expansion/compression processes while heat absorption/rejection of the Otto cycle was determined based on finite time thermodynamics, FTT. In addition, other irreversibility including power loss caused by heat transfer through the cylinder walls and irreversibility due to throttling process was integrated into the model. The developed model was verified by implementing on two different spark ignition internal combustion engines and the results of modeling were compared with experimental results as well as FTT model. It was found that the developed model was not only very simple in use like a closed form thermodynamic model, but also it models a real spark ignition engine with reasonable accuracy. The error in predicting the output power at rated operating range of the engine was 39%, while in the case of the FTT model, this figure was 167.5%. This comparison for predicting thermal efficiency was +7% error (as difference) for the developed model compared to +39.4% error of FTT model.

  17. Problem-based learning biotechnology courses in chemical engineering.

    Science.gov (United States)

    Glatz, Charles E; Gonzalez, Ramon; Huba, Mary E; Mallapragada, Surya K; Narasimhan, Balaji; Reilly, Peter J; Saunders, Kevin P; Shanks, Jacqueline V

    2006-01-01

    We have developed a series of upper undergraduate/graduate lecture and laboratory courses on biotechnological topics to supplement existing biochemical engineering, bioseparations, and biomedical engineering lecture courses. The laboratory courses are based on problem-based learning techniques, featuring two- and three-person teams, journaling, and performance rubrics for guidance and assessment. Participants initially have found them to be difficult, since they had little experience with problem-based learning. To increase enrollment, we are combining the laboratory courses into 2-credit groupings and allowing students to substitute one of them for the second of our 2-credit chemical engineering unit operations laboratory courses.

  18. Engine control system having pressure-based timing

    Science.gov (United States)

    Willi, Martin L [Dunlap, IL; Fiveland, Scott B [Metamora, IL; Montgomery, David T [Edelstein, IL; Gong, Weidong [Dunlap, IL

    2011-10-04

    A control system for an engine having a first cylinder and a second cylinder is disclosed having a first engine valve movable to regulate a fluid flow of the first cylinder and a first actuator associated with the first engine valve. The control system also has a second engine valve movable to regulate a fluid flow of the second cylinder and a sensor configured to generate a signal indicative of a pressure within the first cylinder. The control system also has a controller that is in communication with the first actuator and the sensor. The controller is configured to compare the pressure within the first cylinder with a desired pressure and selectively regulate the first actuator to adjust a timing of the first engine valve independently of the timing of the second engine valve based on the comparison.

  19. Modeling a distributed environment for a petroleum reservoir engineering application with software product line

    International Nuclear Information System (INIS)

    Scheidt, Rafael de Faria; Vilain, Patrícia; Dantas, M A R

    2014-01-01

    Petroleum reservoir engineering is a complex and interesting field that requires large amount of computational facilities to achieve successful results. Usually, software environments for this field are developed without taking care out of possible interactions and extensibilities required by reservoir engineers. In this paper, we present a research work which it is characterized by the design and implementation based on a software product line model for a real distributed reservoir engineering environment. Experimental results indicate successfully the utilization of this approach for the design of distributed software architecture. In addition, all components from the proposal provided greater visibility of the organization and processes for the reservoir engineers

  20. Radioisotope power system based on derivative of existing Stirling engine

    International Nuclear Information System (INIS)

    Schock, A.; Or, C.T.; Kumar, V.

    1995-01-01

    In a recent paper, the authors presented the results of a system design study of a 75-watt(c) RSG (Radioisotope Stirling Generator) for possible application to the Pluto Fast Flyby mission. That study was based on a Stirling engine design generated by MTI (Mechanical Technology, Inc.). The MTI design was a derivative of a much larger (13 kwe) engine that they had developed and tested for NASA's LERC. Clearly, such a derivative would be a major extrapolation (downsizing) from what has actually been built and tested. To avoid that, the present paper describes a design for a 75-watt RSG system based on derivatives of a small (11-watt) engine and linear alternator system that has been under development by STC (Stirling Technology Company) for over three years and that has operated successfully for over 15,000 hours as of March 1995. Thus, the STC engines would require much less extrapolation from proven designs. The design employs a heat source consisting of two standard General Purpose Heat Source (GPHS) modules, coupled to four Stirling engines with linear alternators, any three of which could deliver the desired 75-watt(e) output if the fourth should fail. The four engines are coupled to four common radiators with redundant heatpipes for rejecting the engines' waste heat to space. The above engine and radiator redundancies promote system reliability. The paper describes detailed analyses to determine the effect of radiator geometry on system mass and performance, before and after an engine or heatpipe failure

  1. An Example of Competence-Based Learning: Use of Maxima in Linear Algebra for Engineers

    Science.gov (United States)

    Diaz, Ana; Garcia, Alfonsa; de la Villa, Agustin

    2011-01-01

    This paper analyses the role of Computer Algebra Systems (CAS) in a model of learning based on competences. The proposal is an e-learning model Linear Algebra course for Engineering, which includes the use of a CAS (Maxima) and focuses on problem solving. A reference model has been taken from the Spanish Open University. The proper use of CAS is…

  2. A Comparison of Different Engineering Models for Computation of Lightning Magnetic Field of Negative First Strokes

    Directory of Open Access Journals (Sweden)

    V. Javor

    2012-11-01

    Full Text Available A comparison of different engineering models results for a lightning magnetic field of negative first strokes is presented in this paper. A new function for representing double-peaked channel-base current is used for lightning stroke modeling. This function includes the initial and subsidiary peak in a current waveform. For experimentally measured currents, a magnetic field is calculated for the three engineering models: transmission line (TL model, TL model with linear decay (MTLL, and TL model with exponential decay (MTLE.

  3. Enhancing food engineering education with interactive web-based simulations

    Directory of Open Access Journals (Sweden)

    Alexandros Koulouris

    2015-04-01

    Full Text Available In the traditional deductive approach in teaching any engineering topic, teachers would first expose students to the derivation of the equations that govern the behavior of a physical system and then demonstrate the use of equations through a limited number of textbook examples. This methodology, however, is rarely adequate to unmask the cause-effect and quantitative relationships between the system variables that the equations embody. Web-based simulation, which is the integration of simulation and internet technologies, has the potential to enhance the learning experience by offering an interactive and easily accessible platform for quick and effortless experimentation with physical phenomena.This paper presents the design and development of a web-based platform for teaching basic food engineering phenomena to food technology students. The platform contains a variety of modules (“virtual experiments” covering the topics of mass and energy balances, fluid mechanics and heat transfer. In this paper, the design and development of three modules for mass balances and heat transfer is presented. Each webpage representing an educational module has the following features: visualization of the studied phenomenon through graphs, charts or videos, computation through a mathematical model and experimentation.  The student is allowed to edit key parameters of the phenomenon and observe the effect of these changes on the outputs. Experimentation can be done in a free or guided fashion with a set of prefabricated examples that students can run and self-test their knowledge by answering multiple-choice questions.

  4. Engineering Student's Ethical Awareness and Behavior: A New Motivational Model.

    Science.gov (United States)

    Bairaktarova, Diana; Woodcock, Anna

    2017-08-01

    Professional communities are experiencing scandals involving unethical and illegal practices daily. Yet it should not take a national major structure failure to highlight the importance of ethical awareness and behavior, or the need for the development and practice of ethical behavior in engineering students. Development of ethical behavior skills in future engineers is a key competency for engineering schools as ethical behavior is a part of the professional identity and practice of engineers. While engineering educators have somewhat established instructional methods to teach engineering ethics, they still rely heavily on teaching ethical awareness, and pay little attention to how well ethical awareness predicts ethical behavior. However the ability to exercise ethical judgement does not mean that students are ethically educated or likely to behave in an ethical manner. This paper argues measuring ethical judgment is insufficient for evaluating the teaching of engineering ethics, because ethical awareness has not been demonstrated to translate into ethical behavior. The focus of this paper is to propose a model that correlates with both, ethical awareness and ethical behavior. This model integrates the theory of planned behavior, person and thing orientation, and spheres of control. Applying this model will allow educators to build confidence and trust in their students' ability to build a professional identity and be prepared for the engineering profession and practice.

  5. Mathematical modeling of a four-stroke resonant engine for micro and mesoscale applications

    Science.gov (United States)

    Preetham, B. S.; Anderson, M.; Richards, C.

    2014-12-01

    In order to mitigate frictional and leakage losses in small scale engines, a compliant engine design is proposed in which the piston in cylinder arrangement is replaced by a flexible cavity. A physics-based nonlinear lumped-parameter model is derived to predict the performance of a prototype engine. The model showed that the engine performance depends on input parameters, such as heat input, heat loss, and load on the engine. A sample simulation for a reference engine with octane fuel/air ratio of 0.043 resulted in an indicated thermal efficiency of 41.2%. For a fixed fuel/air ratio, higher output power is obtained for smaller loads and vice-versa. The heat loss from the engine and the work done on the engine during the intake stroke are found to decrease the indicated thermal efficiency. The ratio of friction work to indicated work in the prototype engine is about 8%, which is smaller in comparison to the traditional reciprocating engines.

  6. Dynamic material characterization by combining ballistic testing and an engineering model

    NARCIS (Netherlands)

    Carton, E.P.; Roebroeks, G.H.J.J.; Wal, R. van der

    2013-01-01

    At TNO several energy-based engineering models have been created for various failure mechanism occurring in ballistic testing of materials, like ductile hole growth, denting, plugging, etc. Such models are also under development for ceramic and fiberbased materials (fabrics). As the models are

  7. Experience with performance based training of nuclear criticality safety engineers

    International Nuclear Information System (INIS)

    Taylor, R.G.

    1993-01-01

    For non-reactor nuclear facilities, the U.S. Department of Energy (DOE) does not require that nuclear criticality safety engineers demonstrate qualification for their job. It is likely, however, that more formalism will be required in the future. Current DOE requirements for those positions which do have to demonstrate qualification indicate that qualification should be achieved by using a systematic approach such as performance based training (PBT). Assuming that PBT would be an acceptable mechanism for nuclear criticality safety engineer training in a more formal environment, a site-specific analysis of the nuclear criticality safety engineer job was performed. Based on this analysis, classes are being developed and delivered to a target audience of newer nuclear criticality safety engineers. Because current interest is in developing training for selected aspects of the nuclear criticality safety engineer job, the analysis is incompletely developed in some areas

  8. Compact and Accurate Turbocharger Modelling for Engine Control

    DEFF Research Database (Denmark)

    Sorenson, Spencer C; Hendricks, Elbert; Magnússon, Sigurjón

    2005-01-01

    With the current trend towards engine downsizing, the use of turbochargers to obtain extra engine power has become common. A great díffuculty in the use of turbochargers is in the modelling of the compressor map. In general this is done by inserting the compressor map directly into the engine ECU...... (Engine Control Unit) as a table. This method uses a great deal of memory space and often requires on-line interpolation and thus a large amount of CPU time. In this paper a more compact, accurate and rapid method of dealing with the compressor modelling problem is presented and is applicable to all...... turbocharges with radial compressors for either Spark Ignition (SI) or diesel engines...

  9. Modeling Engineered Nanomaterials (ENMs) Fate and Transport in Aquatic Ecosystems

    Science.gov (United States)

    Under the Toxic Substances Control Act (TSCA), the Environmental Protection Agency (EPA) is required to perform new chemical reviews of engineered nanomaterials (ENMs) identified in pre-manufacture notices. However, environmental fate models developed for traditional contaminants...

  10. Engineered Barrier System: Physical and Chemical Environment Model

    International Nuclear Information System (INIS)

    Jolley, D. M.; Jarek, R.; Mariner, P.

    2004-01-01

    The conceptual and predictive models documented in this Engineered Barrier System: Physical and Chemical Environment Model report describe the evolution of the physical and chemical conditions within the waste emplacement drifts of the repository. The modeling approaches and model output data will be used in the total system performance assessment (TSPA-LA) to assess the performance of the engineered barrier system and the waste form. These models evaluate the range of potential water compositions within the emplacement drifts, resulting from the interaction of introduced materials and minerals in dust with water seeping into the drifts and with aqueous solutions forming by deliquescence of dust (as influenced by atmospheric conditions), and from thermal-hydrological-chemical (THC) processes in the drift. These models also consider the uncertainty and variability in water chemistry inside the drift and the compositions of introduced materials within the drift. This report develops and documents a set of process- and abstraction-level models that constitute the engineered barrier system: physical and chemical environment model. Where possible, these models use information directly from other process model reports as input, which promotes integration among process models used for total system performance assessment. Specific tasks and activities of modeling the physical and chemical environment are included in the technical work plan ''Technical Work Plan for: In-Drift Geochemistry Modeling'' (BSC 2004 [DIRS 166519]). As described in the technical work plan, the development of this report is coordinated with the development of other engineered barrier system analysis model reports

  11. Engineering Seismic Base Layer for Defining Design Earthquake Motion

    International Nuclear Information System (INIS)

    Yoshida, Nozomu

    2008-01-01

    Engineer's common sense that incident wave is common in a widespread area at the engineering seismic base layer is shown not to be correct. An exhibiting example is first shown, which indicates that earthquake motion at the ground surface evaluated by the analysis considering the ground from a seismic bedrock to a ground surface simultaneously (continuous analysis) is different from the one by the analysis in which the ground is separated at the engineering seismic base layer and analyzed separately (separate analysis). The reason is investigated by several approaches. Investigation based on eigen value problem indicates that the first predominant period in the continuous analysis cannot be found in the separate analysis, and predominant period at higher order does not match in the upper and lower ground in the separate analysis. The earthquake response analysis indicates that reflected wave at the engineering seismic base layer is not zero, which indicates that conventional engineering seismic base layer does not work as expected by the term ''base''. All these results indicate that wave that goes down to the deep depths after reflecting in the surface layer and again reflects at the seismic bedrock cannot be neglected in evaluating the response at the ground surface. In other words, interaction between the surface layer and/or layers between seismic bedrock and engineering seismic base layer cannot be neglected in evaluating the earthquake motion at the ground surface

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

    NARCIS (Netherlands)

    dr. Martijn Zoet; Stijn Hoppenbrouwers; Inge van de Weerd; Johan Versendaal

    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

  13. Rotary engine performance limits predicted by a zero-dimensional model

    Science.gov (United States)

    Bartrand, Timothy A.; Willis, Edward A.

    1992-01-01

    A parametric study was performed to determine the performance limits of a rotary combustion engine. This study shows how well increasing the combustion rate, insulating, and turbocharging increase brake power and decrease fuel consumption. Several generalizations can be made from the findings. First, it was shown that the fastest combustion rate is not necessarily the best combustion rate. Second, several engine insulation schemes were employed for a turbocharged engine. Performance improved only for a highly insulated engine. Finally, the variability of turbocompounding and the influence of exhaust port shape were calculated. Rotary engines performance was predicted by an improved zero-dimensional computer model based on a model developed at the Massachusetts Institute of Technology in the 1980's. Independent variables in the study include turbocharging, manifold pressures, wall thermal properties, leakage area, and exhaust port geometry. Additions to the computer programs since its results were last published include turbocharging, manifold modeling, and improved friction power loss calculation. The baseline engine for this study is a single rotor 650 cc direct-injection stratified-charge engine with aluminum housings and a stainless steel rotor. Engine maps are provided for the baseline and turbocharged versions of the engine.

  14. Towards a Curation and Preservation Architecture for CAD Engineering Models

    OpenAIRE

    Ball, Alexander; Patel, Manjula; Ding, Lian

    2008-01-01

    For many decades, computer-aided design (CAD) packages have played an important part in the design of product models within the engineering domain. Within the last ten years, however, the increasing complexity of CAD models and their tighter integration into the workflow of engineering enterprises has led to their becoming the definitive expression of a design.At the same time, a paradigm shift has been emerging whereby manufacturers and construction companies enter into contracts to take res...

  15. MATLAB-Based Teaching Modules in Biochemical Engineering

    Science.gov (United States)

    Lee, Kilho; Comolli, Noelle K.; Kelly, William J.; Huang, Zuyi

    2015-01-01

    Mathematical models play an important role in biochemical engineering. For example, the models developed in the field of systems biology have been used to identify drug targets to treat pathogens such as Pseudomonas aeruginosa in biofilms. In addition, competitive binding models for chromatography processes have been developed to predict expanded…

  16. Reliability-based optimization of engineering structures

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2008-01-01

    The theoretical basis for reliability-based structural optimization within the framework of Bayesian statistical decision theory is briefly described. Reliability-based cost benefit problems are formulated and exemplitied with structural optimization. The basic reliability-based optimization prob...

  17. Biomineralization of Engineered Spider Silk Protein-Based Composite Materials for Bone Tissue Engineering

    Directory of Open Access Journals (Sweden)

    John G. Hardy

    2016-07-01

    Full Text Available Materials based on biodegradable polyesters, such as poly(butylene terephthalate (PBT or poly(butylene terephthalate-co-poly(alkylene glycol terephthalate (PBTAT, have potential application as pro-regenerative scaffolds for bone tissue engineering. Herein, the preparation of films composed of PBT or PBTAT and an engineered spider silk protein, (eADF4(C16, that displays multiple carboxylic acid moieties capable of binding calcium ions and facilitating their biomineralization with calcium carbonate or calcium phosphate is reported. Human mesenchymal stem cells cultured on films mineralized with calcium phosphate show enhanced levels of alkaline phosphatase activity suggesting that such composites have potential use for bone tissue engineering.

  18. Design of nuclear power generation plants adopting model engineering method

    International Nuclear Information System (INIS)

    Waki, Masato

    1983-01-01

    The utilization of model engineering as the method of design has begun about ten years ago in nuclear power generation plants. By this method, the result of design can be confirmed three-dimensionally before actual production, and it is the quick and sure method to meet the various needs in design promptly. The adoption of models aims mainly at the improvement of the quality of design since the high safety is required for nuclear power plants in spite of the complex structure. The layout of nuclear power plants and piping design require the model engineering to arrange rationally enormous quantity of things in a limited period. As the method of model engineering, there are the use of check models and of design models, and recently, the latter method has been mainly taken. The procedure of manufacturing models and engineering is explained. After model engineering has been completed, the model information must be expressed in drawings, and the automation of this process has been attempted by various methods. The computer processing of design is in progress, and its role is explained (CAD system). (Kako, I.)

  19. Considerations for the development of task-based search engines

    DEFF Research Database (Denmark)

    Petcu, Paula; Dragusin, Radu

    2013-01-01

    Based on previous experience from working on a task-based search engine, we present a list of suggestions and ideas for an Information Retrieval (IR) framework that could inform the development of next generation professional search systems. The specific task that we start from is the clinicians......' information need in finding rare disease diagnostic hypotheses at the time and place where medical decisions are made. Our experience from the development of a search engine focused on supporting clinicians in completing this task has provided us valuable insights in what aspects should be considered...... by the developers of vertical search engines....

  20. Visualizing and modelling complex rockfall slopes using game-engine hosted models

    Science.gov (United States)

    Ondercin, Matthew; Hutchinson, D. Jean; Harrap, Rob

    2015-04-01

    Innovations in computing in the past few decades have resulted in entirely new ways to collect 3d geological data and visualize it. For example, new tools and techniques relying on high performance computing capabilities have become widely available, allowing us to model rockfalls with more attention to complexity of the rock slope geometry and rockfall path, with significantly higher quality base data, and with more analytical options. Model results are used to design mitigation solutions, considering the potential paths of the rockfall events and the energy they impart on impacted structures. Such models are currently implemented as general-purpose GIS tools and in specialized programs. These tools are used to inspect geometrical and geomechanical data, model rockfalls, and communicate results to researchers and the larger community. The research reported here explores the notion that 3D game engines provide a high speed, widely accessible platform on which to build rockfall modelling workflows and to provide a new and accessible outreach method. Taking advantage of the in-built physics capability of the 3D game codes, and ability to handle large terrains, these models are rapidly deployed and generate realistic visualizations of rockfall trajectories. Their utility in this area is as yet unproven, but preliminary research shows that they are capable of producing results that are comparable to existing approaches. Furthermore, modelling of case histories shows that the output matches the behaviour that is observed in the field. The key advantage of game-engine hosted models is their accessibility to the general public and to people with little to no knowledge of rockfall hazards. With much of the younger generation being very familiar with 3D environments such as Minecraft, the idea of a game-like simulation is intuitive and thus offers new ways to communicate to the general public. We present results from using the Unity game engine to develop 3D voxel worlds

  1. GEO-ENGINEERING MODELING THROUGH INTERNET INFORMATICS (GEMINI)

    Energy Technology Data Exchange (ETDEWEB)

    W. Lynn Watney; John H. Doveton

    2004-05-13

    GEMINI (Geo-Engineering Modeling through Internet Informatics) is a public-domain web application focused on analysis and modeling of petroleum reservoirs and plays (http://www.kgs.ukans.edu/Gemini/index.html). GEMINI creates a virtual project by ''on-the-fly'' assembly and analysis of on-line data either from the Kansas Geological Survey or uploaded from the user. GEMINI's suite of geological and engineering web applications for reservoir analysis include: (1) petrofacies-based core and log modeling using an interactive relational rock catalog and log analysis modules; (2) a well profile module; (3) interactive cross sections to display ''marked'' wireline logs; (4) deterministic gridding and mapping of petrophysical data; (5) calculation and mapping of layer volumetrics; (6) material balance calculations; (7) PVT calculator; (8) DST analyst, (9) automated hydrocarbon association navigator (KHAN) for database mining, and (10) tutorial and help functions. The Kansas Hydrocarbon Association Navigator (KHAN) utilizes petrophysical databases to estimate hydrocarbon pay or other constituent at a play- or field-scale. Databases analyzed and displayed include digital logs, core analysis and photos, DST, and production data. GEMINI accommodates distant collaborations using secure password protection and authorized access. Assembled data, analyses, charts, and maps can readily be moved to other applications. GEMINI's target audience includes small independents and consultants seeking to find, quantitatively characterize, and develop subtle and bypassed pays by leveraging the growing base of digital data resources. Participating companies involved in the testing and evaluation of GEMINI included Anadarko, BP, Conoco-Phillips, Lario, Mull, Murfin, and Pioneer Resources.

  2. Re-engineering pre-employment check-up systems: a model for improving health services.

    Science.gov (United States)

    Rateb, Said Abdel Hakim; El Nouman, Azza Abdel Razek; Rateb, Moshira Abdel Hakim; Asar, Mohamed Naguib; El Amin, Ayman Mohammed; Gad, Saad abdel Aziz; Mohamed, Mohamed Salah Eldin

    2011-01-01

    The purpose of this paper is to develop a model for improving health services provided by the pre-employment medical fitness check-up system affiliated to Egypt's Health Insurance Organization (HIO). Operations research, notably system re-engineering, is used in six randomly selected centers and findings before and after re-engineering are compared. The re-engineering model follows a systems approach, focusing on three areas: structure, process and outcome. The model is based on six main components: electronic booking, standardized check-up processes, protected medical documents, advanced archiving through an electronic content management (ECM) system, infrastructure development, and capacity building. The model originates mainly from customer needs and expectations. The centers' monthly customer flow increased significantly after re-engineering. The mean time spent per customer cycle improved after re-engineering--18.3 +/- 5.5 minutes as compared to 48.8 +/- 14.5 minutes before. Appointment delay was also significantly decreased from an average 18 to 6.2 days. Both beneficiaries and service providers were significantly more satisfied with the services after re-engineering. The model proves that re-engineering program costs are exceeded by increased revenue. Re-engineering in this study involved multiple structure and process elements. The literature review did not reveal similar re-engineering healthcare packages. Therefore, each element was compared separately. This model is highly recommended for improving service effectiveness and efficiency. This research is the first in Egypt to apply the re-engineering approach to public health systems. Developing user-friendly models for service improvement is an added value.

  3. FY 1999 report on the results of the R and D project on the venture support regional consortium - small-/medium-sized firm creation base type. R and D of a flight model of the satellite posture control use small microwave engine; 1999 nendo chiiki consortium kenkyu kaihatsu jigyo - venture kigyo shiengata chiiki consortium kenkyu kaihatsu jigyo (chusho kigyo sozo kibangata) seika hokokusho. Jinko eisei shisei seigyoyo kogata micro ha engine no furaito model no kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    The R and D were conducted of the posture control use engine with power of 50W or below which is necessary/indispensable for small satellite. In the study, based on the technology seeds on the microwave engine of Advanced Technology Institute, Inc., a flight model was designed/manufactured in consideration of the space environment and launching environment. The following were carried out: X-ray test on CPU used for control circuit; random vibration test in which the rocket launching environment was simulated; heat vacuum test in which the vacuum environment and heat environment in space were simulated. As a result of the tests, development was achieved of a microwave engine flight model of thrust of 0.36 millinewton and of gross power of 22 watt, assuming a small satellite of 100kg class. Further, to simulate weightlessness and the vacuum environment by ground equipment, small electric propulsion which simulated microwave engine was actuated at Japan Microgravity Center at Sunagawa town, Hokkaido. Experiment of the flight of about 10 seconds was successfully made. (NEDO)

  4. The Influence of Engineers' Training Models on Ethics and Civic Education Component in Engineering Courses in Portugal

    Science.gov (United States)

    Monteiro, Fátima; Leite, Carlinda; Rocha, Cristina

    2017-01-01

    The recognition of the need and importance of including ethical and civic education in engineering courses, as well as the training profile on ethical issues, relies heavily on the engineer's concept and the perception of the engineering action. These views are strongly related to the different engineer education model conceptions and its…

  5. D Model Visualization Enhancements in Real-Time Game Engines

    Science.gov (United States)

    Merlo, A.; Sánchez Belenguer, C.; Vendrell Vidal, E.; Fantini, F.; Aliperta, A.

    2013-02-01

    This paper describes two procedures used to disseminate tangible cultural heritage through real-time 3D simulations providing accurate-scientific representations. The main idea is to create simple geometries (with low-poly count) and apply two different texture maps to them: a normal map and a displacement map. There are two ways to achieve models that fit with normal or displacement maps: with the former (normal maps), the number of polygons in the reality-based model may be dramatically reduced by decimation algorithms and then normals may be calculated by rendering them to texture solutions (baking). With the latter, a LOD model is needed; its topology has to be quad-dominant for it to be converted to a good quality subdivision surface (with consistent tangency and curvature all over). The subdivision surface is constructed using methodologies for the construction of assets borrowed from character animation: these techniques have been recently implemented in many entertainment applications known as "retopology". The normal map is used as usual, in order to shade the surface of the model in a realistic way. The displacement map is used to finish, in real-time, the flat faces of the object, by adding the geometric detail missing in the low-poly models. The accuracy of the resulting geometry is progressively refined based on the distance from the viewing point, so the result is like a continuous level of detail, the only difference being that there is no need to create different 3D models for one and the same object. All geometric detail is calculated in real-time according to the displacement map. This approach can be used in Unity, a real-time 3D engine originally designed for developing computer games. It provides a powerful rendering engine, fully integrated with a complete set of intuitive tools and rapid workflows that allow users to easily create interactive 3D contents. With the release of Unity 4.0, new rendering features have been added, including Direct

  6. Observing and modeling nonlinear dynamics in an internal combustion engine

    International Nuclear Information System (INIS)

    Daw, C.S.; Kennel, M.B.; Finney, C.E.; Connolly, F.T.

    1998-01-01

    We propose a low-dimensional, physically motivated, nonlinear map as a model for cyclic combustion variation in spark-ignited internal combustion engines. A key feature is the interaction between stochastic, small-scale fluctuations in engine parameters and nonlinear deterministic coupling between successive engine cycles. Residual cylinder gas from each cycle alters the in-cylinder fuel-air ratio and thus the combustion efficiency in succeeding cycles. The model close-quote s simplicity allows rapid simulation of thousands of engine cycles, permitting statistical studies of cyclic-variation patterns and providing physical insight into this technologically important phenomenon. Using symbol statistics to characterize the noisy dynamics, we find good quantitative matches between our model and experimental time-series measurements. copyright 1998 The American Physical Society

  7. Modeling of combustion noise in helicopter engines

    OpenAIRE

    Livebardon, Thomas

    2015-01-01

    The growth of air traffic at the vicinity of areas at high population density imposes to make quieter aircrafts on aeronautical manufacturers.The engine noise is one of the major contributors to the overall sound levels. Furthermore, the combustion is known to be responsible for a broadband noise generation at low-frequency. The combustion noise can be put into two main mechanisms. The first one is the emission of sound pulses by the unsteady heat release of the combustion process and is call...

  8. Cell-Based Strategies for Meniscus Tissue Engineering

    Science.gov (United States)

    Niu, Wei; Guo, Weimin; Han, Shufeng; Zhu, Yun; Liu, Shuyun; Guo, Quanyi

    2016-01-01

    Meniscus injuries remain a significant challenge due to the poor healing potential of the inner avascular zone. Following a series of studies and clinical trials, tissue engineering is considered a promising prospect for meniscus repair and regeneration. As one of the key factors in tissue engineering, cells are believed to be highly beneficial in generating bionic meniscus structures to replace injured ones in patients. Therefore, cell-based strategies for meniscus tissue engineering play a fundamental role in meniscal regeneration. According to current studies, the main cell-based strategies for meniscus tissue engineering are single cell type strategies; cell coculture strategies also were applied to meniscus tissue engineering. Likewise, on the one side, the zonal recapitulation strategies based on mimicking meniscal differing cells and internal architectures have received wide attentions. On the other side, cell self-assembling strategies without any scaffolds may be a better way to build a bionic meniscus. In this review, we primarily discuss cell seeds for meniscus tissue engineering and their application strategies. We also discuss recent advances and achievements in meniscus repair experiments that further improve our understanding of meniscus tissue engineering. PMID:27274735

  9. Hydrogen engines based on liquid fuels, a review

    Science.gov (United States)

    Houseman, J.; Voecks, G. E.

    1981-01-01

    The concept of storing hydrogen as part of a liquid fuel, such as gasoline or methanol, and subsequent onboard generation of the hydrogen from such liquids, is reviewed. Hydrogen generation processes, such as steam reforming, partial oxidation, and thermal decomposition are evaluated in terms of theoretical potential and practical limitations, and a summary is presented on the major experimental work on conversion of gasoline and methanol. Results of experiments indicate that onboard hydrogen generation from methanol is technically feasible and will yield substantial improvements in fuel economy and emissions, especially if methanol decomposition is brought about by the use of engine exhaust heat; e.g., a methanol decomposition reactor of 3.8 provides hydrogen-rich gas for a 4 cylinder engine (1.952), and 80% of the methanol is converted, engine exhaust gas being the only heat supply. A preliminary outline of the development of a methanol-based hydrogen engine and a straight hydrogen engine is presented.

  10. Modern earthquake engineering offshore and land-based structures

    CERN Document Server

    Jia, Junbo

    2017-01-01

    This book addresses applications of earthquake engineering for both offshore and land-based structures. It is self-contained as a reference work and covers a wide range of topics, including topics related to engineering seismology, geotechnical earthquake engineering, structural engineering, as well as special contents dedicated to design philosophy, determination of ground motions, shock waves, tsunamis, earthquake damage, seismic response of offshore and arctic structures, spatial varied ground motions, simplified and advanced seismic analysis methods, sudden subsidence of offshore platforms, tank liquid impacts during earthquakes, seismic resistance of non-structural elements, and various types of mitigation measures, etc. The target readership includes professionals in offshore and civil engineering, officials and regulators, as well as researchers and students in this field.

  11. An introductory model of a one-piston engine

    International Nuclear Information System (INIS)

    GlarIa, Jaime; Wendler, Thomas; Goodwin, Graham

    2005-01-01

    Reciprocating internal combustion engine models have the antithetical goals of accurately describing complex nonlinear behaviour and being simple enough for such purposes as automatic control and online diagnosis. A one-piston four-stroke engine is modelled here by recursively stating simple physical equations. To do that, the domestic ideas of domination and dependence are called as methodological tools for modelling, since they hand out necessary and sufficient equations with few manoeuvres, allocate simulations with the same characteristic and, hopefully, provide a fine way to understanding. The resulting model reveals both steady cycles and transient behaviour

  12. Generic domain models in software engineering

    Science.gov (United States)

    Maiden, Neil

    1992-01-01

    This paper outlines three research directions related to domain-specific software development: (1) reuse of generic models for domain-specific software development; (2) empirical evidence to determine these generic models, namely elicitation of mental knowledge schema possessed by expert software developers; and (3) exploitation of generic domain models to assist modelling of specific applications. It focuses on knowledge acquisition for domain-specific software development, with emphasis on tool support for the most important phases of software development.

  13. Applications and issues of GIS as tool for civil engineering modeling

    Science.gov (United States)

    Miles, S.B.; Ho, C.L.

    1999-01-01

    A tool that has proliferated within civil engineering in recent years is geographic information systems (GIS). The goal of a tool is to supplement ability and knowledge that already exists, not to serve as a replacement for that which is lacking. To secure the benefits and avoid misuse of a burgeoning tool, engineers must understand the limitations, alternatives, and context of the tool. The common benefits of using GIS as a supplement to engineering modeling are summarized. Several brief case studies of GIS modeling applications are taken from popular civil engineering literature to demonstrate the wide use and varied implementation of GIS across the discipline. Drawing from the case studies, limitations regarding traditional GIS data models find the implementation of civil engineering models within current GIS are identified and countered by discussing the direction of the next generation of GIS. The paper concludes by highlighting the potential for the misuse of GIS in the context of engineering modeling and suggests that this potential can be reduced through education and awareness. The goal of this paper is to promote awareness of the issues related to GIS-based modeling and to assist in the formulation of questions regarding the application of current GIS. The technology has experienced much publicity of late, with many engineers being perhaps too excited about the usefulness of current GIS. An undoubtedly beneficial side effect of this, however, is that engineers are becoming more aware of GIS and, hopefully, the associated subtleties. Civil engineers must stay informed of GIS issues and progress, but more importantly, civil engineers must inform the GIS community to direct the technology development optimally.

  14. Rule-based decision making model

    International Nuclear Information System (INIS)

    Sirola, Miki

    1998-01-01

    A rule-based decision making model is designed in G2 environment. A theoretical and methodological frame for the model is composed and motivated. The rule-based decision making model is based on object-oriented modelling, knowledge engineering and decision theory. The idea of safety objective tree is utilized. Advanced rule-based methodologies are applied. A general decision making model 'decision element' is constructed. The strategy planning of the decision element is based on e.g. value theory and utility theory. A hypothetical process model is built to give input data for the decision element. The basic principle of the object model in decision making is division in tasks. Probability models are used in characterizing component availabilities. Bayes' theorem is used to recalculate the probability figures when new information is got. The model includes simple learning features to save the solution path. A decision analytic interpretation is given to the decision making process. (author)

  15. Cost Risk Analysis Based on Perception of the Engineering Process

    Science.gov (United States)

    Dean, Edwin B.; Wood, Darrell A.; Moore, Arlene A.; Bogart, Edward H.

    1986-01-01

    process parameters are elicited from the engineer/expert on the project and are based on that expert's technical knowledge. These are converted by a parametric cost model into a cost estimate. The method discussed makes no assumptions about the distribution underlying the distribution of possible costs, and is not tied to the analysis of previous projects, except through the expert calibrations performed by the parametric cost analyst.

  16. Evaluation of air pollution modelling tools as environmental engineering courseware.

    Science.gov (United States)

    Souto González, J A; Bello Bugallo, P M; Casares Long, J J

    2004-01-01

    The study of phenomena related to the dispersion of pollutants usually takes advantage of the use of mathematical models based on the description of the different processes involved. This educational approach is especially important in air pollution dispersion, when the processes follow a non-linear behaviour so it is difficult to understand the relationships between inputs and outputs, and in a 3D context where it becomes hard to analyze alphanumeric results. In this work, three different software tools, as computer solvers for typical air pollution dispersion phenomena, are presented. Each software tool developed to be implemented on PCs, follows approaches that represent three generations of programming languages (Fortran 77, VisualBasic and Java), applied over three different environments: MS-DOS, MS-Windows and the world wide web. The software tools were tested by students of environmental engineering (undergraduate) and chemical engineering (postgraduate), in order to evaluate the ability of these software tools to improve both theoretical and practical knowledge of the air pollution dispersion problem, and the impact of the different environment in the learning process in terms of content, ease of use and visualization of results.

  17. Engineering approach to model and compute electric power markets settlements

    International Nuclear Information System (INIS)

    Kumar, J.; Petrov, V.

    2006-01-01

    Back-office accounting settlement activities are an important part of market operations in Independent System Operator (ISO) organizations. A potential way to measure ISO market design correctness is to analyze how well market price signals create incentives or penalties for creating an efficient market to achieve market design goals. Market settlement rules are an important tool for implementing price signals which are fed back to participants via the settlement activities of the ISO. ISO's are currently faced with the challenge of high volumes of data resulting from the increasing size of markets and ever-changing market designs, as well as the growing complexity of wholesale energy settlement business rules. This paper analyzed the problem and presented a practical engineering solution using an approach based on mathematical formulation and modeling of large scale calculations. The paper also presented critical comments on various differences in settlement design approaches to electrical power market design, as well as further areas of development. The paper provided a brief introduction to the wholesale energy market settlement systems and discussed problem formulation. An actual settlement implementation framework and discussion of the results and conclusions were also presented. It was concluded that a proper engineering approach to this domain can yield satisfying results by formalizing wholesale energy settlements. Significant improvements were observed in the initial preparation phase, scoping and effort estimation, implementation and testing. 5 refs., 2 figs

  18. Decision models in engineering and management

    CERN Document Server

    2015-01-01

    Providing a comprehensive overview of various methods  and applications in decision engineering, this book presents chapters written by a range experts in the field. It presents conceptual aspects of decision support applications in various areas including finance, vendor selection, construction, process management, water management and energy, agribusiness , production scheduling and control, and waste management. In addition to this, a special focus is given to methods of multi-criteria decision analysis. Decision making in organizations is a recurrent theme and is essential for business continuity.  Managers from various fields including public, private, industrial, trading or service sectors are required to make decisions. Consequently managers need the support of these structured methods in order to engage in effective decision making. This book provides a valuable resource for graduate students, professors and researchers of decision analysis, multi-criteria decision analysis and group decision analys...

  19. A WEAR MODEL FOR DIESEL ENGINE EXHAUST VALVES

    Energy Technology Data Exchange (ETDEWEB)

    Blau, Peter Julian [ORNL

    2009-11-01

    The work summarized here comprises the concluding effort of a multi-year project, funded by the U.S. Department of Energy, Office of Vehicle Technologies. It supports the development of a better understanding of advanced diesel engine designs in which enhanced power density, energy efficiency, and emissions control place increasing demands upon the durability of engine materials. Many kinds of metallic alloys are used in engines depending on the operating stresses, temperatures, and chemical environments. Exhaust valves, for example, are subjected to high temperatures and repetitive surface contacts that place demands on durability and frictional characteristics of the materials. Valves must continue to seal the combustion chamber properly for thousands of hours of cyclic engine operation and under varying operating conditions. It was the focus of this effort to understand the wear processes in the valve-seat area and to develop a model for the surface deformation and wear of that important interface. An annotated bibliography is provided to illustrate efforts to understand valve wear and to investigate the factors of engine operation that affect its severity and physical manifestation. The project for which this modeling effort was the final task, involved construction of a high-temperature repetitive impact test system as well as basic tribology studies of the combined processes of mechanical wear plus oxidation at elevated temperatures. Several publications resulted from this work, and are cited in this report. The materials selected for the experimental work were high-performance alloys based on nickel and cobalt. In some cases, engine-tested exhaust valves were made available for wear analysis and to ensure that the modes of surface damage produced in experiments were simulative of service. New, production-grade exhaust valves were also used to prepare test specimens for experimental work along with the other alloy samples. Wear analysis of valves and seats

  20. V&V Within Reuse-Based Software Engineering

    Science.gov (United States)

    Addy, Edward A.

    1996-01-01

    Verification and Validation (V&V) is used to increase the level of assurance of critical software, particularly that of safety-critical and mission-critical software. V&V is a systems engineering discipline that evaluates the software in a systems context, and is currently applied during the development of a specific application system. In order to bring the effectiveness of V&V to bear within reuse-based software engineering, V&V must be incorporated within the domain engineering process.

  1. Review: Polymeric-Based 3D Printing for Tissue Engineering.

    Science.gov (United States)

    Wu, Geng-Hsi; Hsu, Shan-Hui

    Three-dimensional (3D) printing, also referred to as additive manufacturing, is a technology that allows for customized fabrication through computer-aided design. 3D printing has many advantages in the fabrication of tissue engineering scaffolds, including fast fabrication, high precision, and customized production. Suitable scaffolds can be designed and custom-made based on medical images such as those obtained from computed tomography. Many 3D printing methods have been employed for tissue engineering. There are advantages and limitations for each method. Future areas of interest and progress are the development of new 3D printing platforms, scaffold design software, and materials for tissue engineering applications.

  2. Fire-safety engineering and performance-based codes

    DEFF Research Database (Denmark)

    Sørensen, Lars Schiøtt

    thermodynamics • Heat exchange during the fire process • Skin burns • Burning rate, energy release rate and design fires • Proposal to Risk-based design fires • Proposal to a Fire scale • Material ignition and flame spread • Fire dynamics in buildings • Combustion products and toxic gases • Smoke inhalation......Fire-safety Engineering is written as a textbook for Engineering students at universities and other institutions of higher education that teach in the area of fire. The book can also be used as a work of reference for consulting engineers, Building product manufacturers, contractors, building...

  3. WDM Systems and Networks Modeling, Simulation, Design and Engineering

    CERN Document Server

    Ellinas, Georgios; Roudas, Ioannis

    2012-01-01

    WDM Systems and Networks: Modeling, Simulation, Design and Engineering provides readers with the basic skills, concepts, and design techniques used to begin design and engineering of optical communication systems and networks at various layers. The latest semi-analytical system simulation techniques are applied to optical WDM systems and networks, and a review of the various current areas of optical communications is presented. Simulation is mixed with experimental verification and engineering to present the industry as well as state-of-the-art research. This contributed volume is divided into three parts, accommodating different readers interested in various types of networks and applications. The first part of the book presents modeling approaches and simulation tools mainly for the physical layer including transmission effects, devices, subsystems, and systems), whereas the second part features more engineering/design issues for various types of optical systems including ULH, access, and in-building system...

  4. Experimental study on distributed optical fiber-based approach monitoring saturation line in levee engineering

    Science.gov (United States)

    Su, Huaizhi; Li, Hao; Kang, Yeyuan; Wen, Zhiping

    2018-02-01

    Seepage is one of key factors which affect the levee engineering safety. The seepage danger without timely detection and rapid response may likely lead to severe accidents such as seepage failure, slope instability, and even levee break. More than 90 percent of levee break events are caused by the seepage. It is very important for seepage behavior identification to determine accurately saturation line in levee engineering. Furthermore, the location of saturation line has a major impact on slope stability in levee engineering. Considering the structure characteristics and service condition of levee engineering, the distributed optical fiber sensing technology is introduced to implement the real-time observation of saturation line in levee engineering. The distributed optical fiber temperature sensor system (DTS)-based monitoring principle of saturation line in levee engineering is investigated. An experimental platform, which consists of DTS, heating system, water-supply system, auxiliary analysis system and levee model, is designed and constructed. The monitoring experiment of saturation line in levee model is implemented on this platform. According to the experimental results, the numerical relationship between moisture content and thermal conductivity in porous medium is identified. A line heat source-based distributed optical fiber method obtaining the thermal conductivity in porous medium is developed. A DTS-based approach is proposed to monitor the saturation line in levee engineering. The embedment pattern of optical fiber for monitoring saturation line is presented.

  5. Mechanical Modelling and Computational Issues in Civil Engineering

    OpenAIRE

    FREMOND, M; MACERI, F

    2005-01-01

    In this edited book various novel approaches to problems of modern civil engineering are demonstrated. Experts associated within the Lagrange Laboratory present recent research results in civil engineering dealing both with modelling and computational aspects. Many modern topics are covered, such as monumental dams, soil mechanics and geotechnics, granular media, contact and friction problems, damage and fracture, new structural materials, and vibration damping -presenting the state of the ar...

  6. Multiscale computer modeling in biomechanics and biomedical engineering

    CERN Document Server

    2013-01-01

    This book reviews the state-of-the-art in multiscale computer modeling, in terms of both accomplishments and challenges. The information in the book is particularly useful for biomedical engineers, medical physicists and researchers in systems biology, mathematical biology, micro-biomechanics and biomaterials who are interested in how to bridge between traditional biomedical engineering work at the organ and tissue scales, and the newer arenas of cellular and molecular bioengineering.

  7. Introducing Risk Management Techniques Within Project Based Software Engineering Courses

    Science.gov (United States)

    Port, Daniel; Boehm, Barry

    2002-03-01

    In 1996, USC switched its core two-semester software engineering course from a hypothetical-project, homework-and-exam course based on the Bloom taxonomy of educational objectives (knowledge, comprehension, application, analysis, synthesis, and evaluation). The revised course is a real-client team-project course based on the CRESST model of learning objectives (content understanding, problem solving, collaboration, communication, and self-regulation). We used the CRESST cognitive demands analysis to determine the necessary student skills required for software risk management and the other major project activities, and have been refining the approach over the last 5 years of experience, including revised versions for one-semester undergraduate and graduate project course at Columbia. This paper summarizes our experiences in evolving the risk management aspects of the project course. These have helped us mature more general techniques such as risk-driven specifications, domain-specific simplifier and complicator lists, and the schedule as an independent variable (SAIV) process model. The largely positive results in terms of review of pass / fail rates, client evaluations, product adoption rates, and hiring manager feedback are summarized as well.

  8. Modeling and Engineering Algorithms for Mobile Data

    DEFF Research Database (Denmark)

    Blunck, Henrik; Hinrichs, Klaus; Sondern, Joëlle

    2006-01-01

    In this paper, we present an object-oriented approach to modeling mobile data and algorithms operating on such data. Our model is general enough to capture any kind of continuous motion while at the same time allowing for encompassing algorithms optimized for specific types of motion. Such motion...

  9. Thermodynamic modeling of direct injection methanol fueled engines

    International Nuclear Information System (INIS)

    Shen Yuan; Bedford, Joshua; Wichman, Indrek S.

    2009-01-01

    In-cylinder pressure is an important parameter that is used to investigate the combustion process in internal combustion (IC) engines. In this paper, a thermodynamic model of IC engine combustion is presented and examined. A heat release function and an empirical conversion efficiency factor are introduced to solve the model. The pressure traces obtained by solving the thermodynamic model are compared with measured pressure data for a fully instrumented laboratory IC spark ignition (SI) engine. Derived scaling parameters for time to peak pressure, peak pressure, and maximum rate of pressure rise (among others) are developed and compared with the numerical simulations. The models examined here may serve as pedagogic tools and, when suitably refined, as preliminary design tools.

  10. 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. SM...... drives the optimization iterates of the time-intensive model using the fast model. Several algorithms have been developed for SM optimization, including the original SM algorithm, Aggressive Space Mapping (ASM), Trust Region Aggressive Space Mapping (TRASM) and Hybrid Aggressive Space Mapping (HASM...

  11. Human Modeling For Ground Processing Human Factors Engineering Analysis

    Science.gov (United States)

    Tran, Donald; Stambolian, Damon; Henderson, Gena; Barth, Tim

    2011-01-01

    There have been many advancements and accomplishments over that last few years using human modeling for human factors engineering analysis for design of spacecraft and launch vehicles. The key methods used for this are motion capture and computer generated human models. The focus of this paper is to explain the different types of human modeling used currently and in the past at Kennedy Space Center (KSC) currently, and to explain the future plans for human modeling for future spacecraft designs.

  12. Brazilian minipig as a large-animal model for basic research and stem cell-based tissue engineering. Characterization and in vitro differentiation of bone marrow-derived mesenchymal stem cells.

    Science.gov (United States)

    Stramandinoli-Zanicotti, Roberta Targa; Carvalho, André Lopes; Rebelatto, Carmen Lúcia Kuniyoshi; Sassi, Laurindo Moacir; Torres, Maria Fernanda; Senegaglia, Alexandra Cristina; Boldrinileite, Lidiane Maria; Correa-Dominguez, Alejandro; Kuligovsky, Crisciele; Brofman, Paulo Roberto Slud

    2014-06-01

    Stem cell-based regenerative medicine is one of the most intensively researched medical issues. Pre-clinical studies in a large-animal model, especially in swine or miniature pigs, are highly relevant to human applications. Mesenchymal stem cells (MSCs) have been isolated and expanded from different sources. This study aimed at isolating and characterizing, for the first time, bone marrow-derived MSCs (BM-MSCs) from a Brazilian minipig (BR1). Also, this aimed to validate a new large-animal model for stem cell-based tissue engineering. Bone marrow (BM) was aspirated from the posterior iliac crest of twelve adult male BR1 under general anesthesia. MSCs were selected by plastic-adherence as originally described by Friedenstein. Cell morphology, surface marker expression, and cellular differentiation were examined. The immunophenotypic profile was determined by flow cytometry. The differentiation potential was assessed by cytological staining and by RT-PCR. MSCs were present in all minipig BM samples. These cells showed fibroblastic morphology and were positive for the surface markers CD90 (88.6%), CD29 (89.8%), CD44 (86.9%) and negative for CD34 (1.61%), CD45 (1.83%), CD14 (1.77%) and MHC-II (2.69%). MSCs were differentiated into adipocytes, osteoblasts, and chondroblasts as demonstrated by the presence of lipidic-rich vacuoles, the mineralized extracellular matrix, and the great presence of glycosaminoglycans, respectively. The higher gene expression of adipocyte fatty-acid binding protein (AP2), alkaline phosphatase (ALP) and collagen type 2 (COLII) also confirmed the trilineage differentiation (panimal eligible as a useful large-animal model for stem cell-based studies in Brazil.

  13. Mathematical Modelling in Engineering: A Proposal to Introduce Linear Algebra Concepts

    Science.gov (United States)

    Cárcamo Bahamonde, Andrea; Gómez Urgelles, Joan; Fortuny Aymemí, Josep

    2016-01-01

    The modern dynamic world requires that basic science courses for engineering, including linear algebra, emphasise the development of mathematical abilities primarily associated with modelling and interpreting, which are not exclusively calculus abilities. Considering this, an instructional design was created based on mathematical modelling and…

  14. Modeling the Anisotropic Reflectance of a Surface with Microstructure Engineered to Obtain Visible Contrast after Rotation

    DEFF Research Database (Denmark)

    Luongo, Andrea; Falster, Viggo; Doest, Mads Emil Brix

    2017-01-01

    rotating it 90 degrees around its normal axis. We build an analytic anisotropic reflectance model based on the microstructure engineered to obtain such contrast. Using our model to render synthetic images, we predict the above mentioned contrasts and compare our predictions with the measurements reported...

  15. Strategies for the Curation of CAD Engineering Models

    Directory of Open Access Journals (Sweden)

    Manjula Patel

    2009-06-01

    Full Text Available Normal 0 Product Lifecycle Management (PLM has become increasingly important in the engineering community over the last decade or so, due to the globalisation of markets and the rising popularity of products provided as services. It demands the efficient capture, representation, organisation, retrieval and reuse of product data over its entire life. Simultaneously, there is now a much greater reliance on CAD models for communicating designs to manufacturers, builders, maintenance crews and regulators, and for definitively expressing designs. Creating the engineering record digitally, however, presents problems not only for its long-term maintenance and accessibility - due in part to the rapid obsolescence of the hardware, software and file formats involved - but also for recording the evolution of designs, artefacts and products. We examine the curation and preservation requirements in PLM and suggest ways of alleviating the problems of sustaining CAD engineering models through the use of lightweight formats, layered annotation and the collection of Representation Information as defined in the Open Archival Information System (OAIS Reference Model.  We describe two tools which have been specifically developed to aid in the curation of CAD engineering models in the context of PLM: Lightweight Models with Multilayered Annotation (LiMMA and a Registry/Repository of Representation Information for Engineering (RRoRIfE.

  16. Two-Compartment Pharmacokinetic Models for Chemical Engineers

    Science.gov (United States)

    Kanneganti, Kumud; Simon, Laurent

    2011-01-01

    The transport of potassium permanganate between two continuous-stirred vessels was investigated to help chemical and biomedical engineering students understand two-compartment pharmacokinetic models. Concepts of modeling, mass balance, parameter estimation and Laplace transform were applied to the two-unit process. A good agreement was achieved…

  17. A Team Building Model for Software Engineering Courses Term Projects

    Science.gov (United States)

    Sahin, Yasar Guneri

    2011-01-01

    This paper proposes a new model for team building, which enables teachers to build coherent teams rapidly and fairly for the term projects of software engineering courses. Moreover, the model can also be used to build teams for any type of project, if the team member candidates are students, or if they are inexperienced on a certain subject. The…

  18. Modeling for Control of a Wobble–Yoke Stirling Engine

    NARCIS (Netherlands)

    García–Canseco, Eloísa; Scherpen, Jacquelien M.A.; Kuindersma, Marnix

    2009-01-01

    In this paper we derive the dynamic model of a four–cylinder double–acting wobble–yoke Stirling engine. In contrast with the classical thermodynamics methods that dominate the literature of Stirling mechanisms, we present a control system perspective to obtain a useful model for the analysis and

  19. Performance Characteristics of Automotive Engines in the United States : Report No. 7. Mercedes Benz Model OM617 Diesel Engine.

    Science.gov (United States)

    1977-01-01

    Experimental data were obtained in dynamometer tests of the Mercedes Benz Model OM617 diesel engine to determine fuel consumption and emissions (hydrocarbon, carbon monoxide, oxides of nitroge, and smoke) at steady-state engine-operating modes. The o...

  20. Web Based VRML Modelling

    NARCIS (Netherlands)

    Kiss, S.; Sarfraz, M.

    2004-01-01

    Presents a method to connect VRML (Virtual Reality Modeling Language) and Java components in a Web page using EAI (External Authoring Interface), which makes it possible to interactively generate and edit VRML meshes. The meshes used are based on regular grids, to provide an interaction and modeling

  1. Web Based VRML Modelling

    NARCIS (Netherlands)

    Kiss, S.; Banissi, E.; Khosrowshahi, F.; Sarfraz, M.; Ursyn, A.

    2001-01-01

    Presents a method to connect VRML (Virtual Reality Modeling Language) and Java components in a Web page using EAI (External Authoring Interface), which makes it possible to interactively generate and edit VRML meshes. The meshes used are based on regular grids, to provide an interaction and modeling

  2. Meteoroid Environment Modeling: the Meteoroid Engineering Model and Shower Forecasting

    Science.gov (United States)

    Moorhead, Althea V.

    2017-01-01

    The meteoroid environment is often divided conceptually into meteor showers plus a sporadic background component. The sporadic complex poses the bulk of the risk to spacecraft, but showers can produce significant short-term enhancements of the meteoroid flux. The Meteoroid Environment Office (MEO) has produced two environment models to handle these cases: the Meteoroid Engineering Model (MEM) and an annual meteor shower forecast. Both MEM and the forecast are used by multiple manned spaceflight projects in their meteoroid risk evaluation, and both tools are being revised to incorporate recent meteor velocity, density, and timing measurements. MEM describes the sporadic meteoroid complex and calculates the flux, speed, and directionality of the meteoroid environment relative to a user-supplied spacecraft trajectory, taking the spacecraft's motion into account. MEM is valid in the inner solar system and offers near-Earth and cis-lunar environments. While the current version of MEM offers a nominal meteoroid environment corresponding to a single meteoroid bulk density, the next version of MEMR3 will offer both flux uncertainties and a density distribution in addition to a revised near-Earth environment. We have updated the near-Earth meteor speed distribution and have made the first determination of uncertainty in this distribution. We have also derived a meteor density distribution from the work of Kikwaya et al. (2011). The annual meteor shower forecast takes the form of a report and data tables that can be used in conjunction with an existing MEM assessment. Fluxes are typically quoted to a constant limiting kinetic energy in order to comport with commonly used ballistic limit equations. For the 2017 annual forecast, the MEO substantially revised the list of showers and their characteristics using 14 years of meteor flux measurements from the Canadian Meteor Orbit Radar (CMOR). Defunct or insignificant showers were removed and the temporal profiles of many showers

  3. Engineering a new mouse model for vitiligo.

    Science.gov (United States)

    Manga, Prashiela; Orlow, Seth J

    2012-07-01

    Although the precise mechanisms that trigger vitiligo remain elusive, autoimmune responses mediate its progression. The development of therapies has been impeded by a paucity of animal models, since mice lack interfollicular melanocytes, the primary targets in vitiligo. In this issue, Harris et al. describe a mouse model in which interfollicular melanocytes are retained by Kit ligand overexpression and an immune response is initiated by transplanting melanocyte-targeting CD8+ T cells.

  4. A unified architecture for biomedical search engines based on semantic web technologies.

    Science.gov (United States)

    Jalali, Vahid; Matash Borujerdi, Mohammad Reza

    2011-04-01

    There is a huge growth in the volume of published biomedical research in recent years. Many medical search engines are designed and developed to address the over growing information needs of biomedical experts and curators. Significant progress has been made in utilizing the knowledge embedded in medical ontologies and controlled vocabularies to assist these engines. However, the lack of common architecture for utilized ontologies and overall retrieval process, hampers evaluating different search engines and interoperability between them under unified conditions. In this paper, a unified architecture for medical search engines is introduced. Proposed model contains standard schemas declared in semantic web languages for ontologies and documents used by search engines. Unified models for annotation and retrieval processes are other parts of introduced architecture. A sample search engine is also designed and implemented based on the proposed architecture in this paper. The search engine is evaluated using two test collections and results are reported in terms of precision vs. recall and mean average precision for different approaches used by this search engine.

  5. Mathematical Modelling in Engineering: An Alternative Way to Teach Linear Algebra

    Science.gov (United States)

    Domínguez-García, S.; García-Planas, M. I.; Taberna, J.

    2016-01-01

    Technological advances require that basic science courses for engineering, including Linear Algebra, emphasize the development of mathematical strengths associated with modelling and interpretation of results, which are not limited only to calculus abilities. Based on this consideration, we have proposed a project-based learning, giving a dynamic…

  6. Optimization of Aero Engine Acceleration Control in Combat State Based on Genetic Algorithms

    Science.gov (United States)

    Li, Jie; Fan, Ding; Sreeram, Victor

    2012-03-01

    In order to drastically exploit the potential of the aero engine and improve acceleration performance in the combat state, an on-line optimized controller based on genetic algorithms is designed for an aero engine. For testing the validity of the presented control method, detailed joint simulation tests of the designed controller and the aero engine model are performed in the whole flight envelope. Simulation test results show that the presented control algorithm has characteristics of rapid convergence speed, high efficiency and can fully exploit the acceleration performance potential of the aero engine. Compared with the former controller, the designed on-line optimized controller (DOOC) can improve the security of the acceleration process and greatly enhance the aero engine thrust in the whole range of the flight envelope, the thrust increases an average of 8.1% in the randomly selected working states. The plane which adopts DOOC can acquire better fighting advantage in the combat state.

  7. Simulation of Road Traffic Applying Model-Driven Engineering

    Directory of Open Access Journals (Sweden)

    Alberto FERNÁNDEZ-ISABEL

    2016-05-01

    Full Text Available Road traffic is an important phenomenon in modern societies. The study of its different aspects in the multiple scenarios where it happens is relevant for a huge number of problems. At the same time, its scale and complexity make it hard to study. Traffic simulations can alleviate these difficulties, simplifying the scenarios to consider and controlling their variables. However, their development also presents difficulties. The main ones come from the need to integrate the way of working of researchers and developers from multiple fields. Model-Driven Engineering (MDE addresses these problems using Modelling Languages (MLs and semi-automatic transformations to organise and describe the development, from requirements to code. This paper presents a domain-specific MDE framework for simulations of road traffic. It comprises an extensible ML, support tools, and development guidelines. The ML adopts an agent-based approach, which is focused on the roles of individuals in road traffic and their decision-making. A case study shows the process to model a traffic theory with the ML, and how to specialise that specification for an existing target platform and its simulations. The results are the basis for comparison with related work.

  8. A Network-Based Electrical Engineering Laboratory

    Science.gov (United States)

    Asimopoulos, Nikolaos D.; Kyriakos, Nathanail; Mpatzakis, Vlasios

    2007-01-01

    Technical education is, by definition, a field that requires hands-on practice and experience by the student. When it comes to distant learning, technical education suffers from lack of such practical study, given the fact that e-learning is based on theoretical material being provided remotely to the student. This article presents the idea of…

  9. Engineering virtual environment based training simulators

    NARCIS (Netherlands)

    Jense, G.J.; Kuijper, F.

    1998-01-01

    While the potential of Virtual Environments (VE's) for training simulators has been recognized right from the start of the emergence of the technology, to date most VE systems that claim to be training simulators have been developed in an adhoc fashion. Based on requirements of the Royal Netherlands

  10. Bioinstrumentation: A Project-Based Engineering Course

    Science.gov (United States)

    Kyle, Aaron M.; Jangraw, David C.; Bouchard, Matthew B.; Downs, Matthew E.

    2016-01-01

    This paper presents the development, implementation, and assessment of a project-based Bioinstrumentation course. All course lectures and hands-on laboratory activities are related to a central project theme: a cardiac pacemaker. The students create a benchtop cardiac pacemaker by applying instrumentation knowledge acquired in the course to each…

  11. Case Based Reasoning in Engineering Design

    Science.gov (United States)

    1993-06-30

    Physics Based on Confluences. Artificial Intelligence 24:7-83, 1984. [7] Didier Dubois and Henri Prade . Possibility Theory: An Approach to...in Design. PhD thesis, Massachusetts Institute of Technology, 1982. [53] Rosenauer, N. and A.H. Willis . Kinematics of Mechanisms. Associated General

  12. Engineered Barrier System: Physical and Chemical Environment Model

    Energy Technology Data Exchange (ETDEWEB)

    D. M. Jolley; R. Jarek; P. Mariner

    2004-02-09

    The conceptual and predictive models documented in this Engineered Barrier System: Physical and Chemical Environment Model report describe the evolution of the physical and chemical conditions within the waste emplacement drifts of the repository. The modeling approaches and model output data will be used in the total system performance assessment (TSPA-LA) to assess the performance of the engineered barrier system and the waste form. These models evaluate the range of potential water compositions within the emplacement drifts, resulting from the interaction of introduced materials and minerals in dust with water seeping into the drifts and with aqueous solutions forming by deliquescence of dust (as influenced by atmospheric conditions), and from thermal-hydrological-chemical (THC) processes in the drift. These models also consider the uncertainty and variability in water chemistry inside the drift and the compositions of introduced materials within the drift. This report develops and documents a set of process- and abstraction-level models that constitute the engineered barrier system: physical and chemical environment model. Where possible, these models use information directly from other process model reports as input, which promotes integration among process models used for total system performance assessment. Specific tasks and activities of modeling the physical and chemical environment are included in the technical work plan ''Technical Work Plan for: In-Drift Geochemistry Modeling'' (BSC 2004 [DIRS 166519]). As described in the technical work plan, the development of this report is coordinated with the development of other engineered barrier system analysis model reports.

  13. Anti-angiogenesis therapy based on the bone marrow-derived stromal cells genetically engineered to express sFlt-1 in mouse tumor model

    Directory of Open Access Journals (Sweden)

    Chen X-C

    2008-10-01

    Full Text Available Abstract Background Bone marrow-derived stromal cells (BMSCs are important for development, tissue cell replenishment, and wound healing in physiological and pathological conditions. BMSCs were found to preferably reach sites undergoing the process of cell proliferation, such as wound and tumor, suggesting that BMSCs may be used as a vehicle for gene therapy of tumor. Methods Mouse BMSCs were loaded with recombinant adenoviruses which express soluble Vascular Endothelial Growth Factor Receptor-1 (sFlt-1. The anti-angiogenesis of sFlt-1 in BMSCs was determined using endothelial cells proliferation inhibition assay and alginate encapsulation assay. The anti-tumor effects of BMSCs expressing sFlt-1 through tail-vein infusion were evaluated in two mouse tumor metastases models. Results BMSCs genetically modified with Adv-GFP-sFlt-1 could effectively express and secret sFlt-1. BMSCs loaded with sFlt-1 gene could preferentially home to tumor loci and decrease lung metastases and prolong lifespan in mouse tumor model through inducing anti-angiogenesis and apoptosis in tumors. Conclusion We demonstrated that BMSCs might be employed as a promising vehicle for tumor gene therapy which can effectively not only improve the concentration of anticancer therapeutics in tumors, but also modify the tumor microenvironment.

  14. A Mathematical Model of Marine Diesel Engine Speed Control System

    Science.gov (United States)

    Sinha, Rajendra Prasad; Balaji, Rajoo

    2018-02-01

    Diesel engine is inherently an unstable machine and requires a reliable control system to regulate its speed for safe and efficient operation. Also, the diesel engine may operate at fixed or variable speeds depending upon user's needs and accordingly the speed control system should have essential features to fulfil these requirements. This paper proposes a mathematical model of a marine diesel engine speed control system with droop governing function. The mathematical model includes static and dynamic characteristics of the control loop components. Model of static characteristic of the rotating fly weights speed sensing element provides an insight into the speed droop features of the speed controller. Because of big size and large time delay, the turbo charged diesel engine is represented as a first order system or sometimes even simplified to a pure integrator with constant gain which is considered acceptable in control literature. The proposed model is mathematically less complex and quick to use for preliminary analysis of the diesel engine speed controller performance.

  15. Model Validation in Ontology Based Transformations

    Directory of Open Access Journals (Sweden)

    Jesús M. Almendros-Jiménez

    2012-10-01

    Full Text Available Model Driven Engineering (MDE is an emerging approach of software engineering. MDE emphasizes the construction of models from which the implementation should be derived by applying model transformations. The Ontology Definition Meta-model (ODM has been proposed as a profile for UML models of the Web Ontology Language (OWL. In this context, transformations of UML models can be mapped into ODM/OWL transformations. On the other hand, model validation is a crucial task in model transformation. Meta-modeling permits to give a syntactic structure to source and target models. However, semantic requirements have to be imposed on source and target models. A given transformation will be sound when source and target models fulfill the syntactic and semantic requirements. In this paper, we present an approach for model validation in ODM based transformations. Adopting a logic programming based transformational approach we will show how it is possible to transform and validate models. Properties to be validated range from structural and semantic requirements of models (pre and post conditions to properties of the transformation (invariants. The approach has been applied to a well-known example of model transformation: the Entity-Relationship (ER to Relational Model (RM transformation.

  16. Semantic Web and Model-Driven Engineering

    CERN Document Server

    Parreiras, Fernando S

    2012-01-01

    The next enterprise computing era will rely on the synergy between both technologies: semantic web and model-driven software development (MDSD). The semantic web organizes system knowledge in conceptual domains according to its meaning. It addresses various enterprise computing needs by identifying, abstracting and rationalizing commonalities, and checking for inconsistencies across system specifications. On the other side, model-driven software development is closing the gap among business requirements, designs and executables by using domain-specific languages with custom-built syntax and se

  17. Functional Security Model: Managers Engineers Working Together

    Science.gov (United States)

    Guillen, Edward Paul; Quintero, Rulfo

    2008-05-01

    Information security has a wide variety of solutions including security policies, network architectures and technological applications, they are usually designed and implemented by security architects, but in its own complexity this solutions are difficult to understand by company managers and they are who finally fund the security project. The main goal of the functional security model is to achieve a solid security platform reliable and understandable in the whole company without leaving of side the rigor of the recommendations and the laws compliance in a single frame. This paper shows a general scheme of the model with the use of important standards and tries to give an integrated solution.

  18. Subcontinuum thermal transport in tip-based thermal engineering

    Science.gov (United States)

    Hamian, Sina

    For the past two decades, tip-based thermal engineering has made remarkable advances to realize unprecedented nanoscale thermal applications, such as thermomechanical data storage, thermophysical/chemical property characterization of materials in nanometer scale, and scanning thermal imaging and analysis. All these applications involve localized heating with elevated temperature, generally in the order of mean free paths of heat carriers, thus necessitates fundamental understanding of sub-continuum thermal transport across point constrictions and within thin films. Considering the demands, this dissertation is divided into three main scopes providing: (1) a numerical model that provides insight onto nanoscale thermal transport, (2) an electrothermal characterization of a heated microcantilever as a localized heating source, and (3) qualitative measurement of tip-substrate thermal transport using high resolution nanothermometer/heater. This dissertation starts with a literature review on the three aforementioned scopes followed by a numerical model for two-dimensional transient ballistic-diffusive heat transfer combining finite element analysis with discrete ordinate method (DOM-FEA), seeking to provide insight on subcontinuum thermal transport. The phonon Boltzmann transport equation (BTE) under grey relaxation time approximation is solved for different Knudsen numbers. Next, a thermal microcantilever, as one of the main tools in tip-based thermal engineering, is characterized under periodic heating operation in air and vacuum using 3o technique. A three-dimensional FEA simulation of a thermal microcantilever is used to model heat transfer in frequency domain resulting in good agreement with the experiment. Next, quantitative thermal transport is measured by a home-built nanothermometer fabricated using combination of electron-beam lithography and photolithography. An atomic force microscope (AFM) cantilever is used to scan over the sensing probe of the

  19. Genetically engineered mouse models of prostate cancer

    NARCIS (Netherlands)

    Nawijn, Martijn C.; Bergman, Andreas M.; van der Poel, Henk G.

    Objectives: Mouse models of prostate cancer are used to test the contribution of individual genes to the transformation process, evaluate the collaboration between multiple genetic lesions observed in a single tumour, and perform preclinical intervention studies in prostate cancer research. Methods:

  20. Knowledge-based engineering of a PLC controlled telescope

    Science.gov (United States)

    Pessemier, Wim; Raskin, Gert; Saey, Philippe; Van Winckel, Hans; Deconinck, Geert

    2016-08-01

    As the new control system of the Mercator Telescope is being finalized, we can review some technologies and design methodologies that are advantageous, despite their relative uncommonness in astronomical instrumentation. Particular for the Mercator Telescope is that it is controlled by a single high-end soft-PLC (Programmable Logic Controller). Using off-the-shelf components only, our distributed embedded system controls all subsystems of the telescope such as the pneumatic primary mirror support, the hydrostatic bearing, the telescope axes, the dome, the safety system, and so on. We show how real-time application logic can be written conveniently in typical PLC languages (IEC 61131-3) and in C++ (to implement the pointing kernel) using the commercial TwinCAT 3 programming environment. This software processes the inputs and outputs of the distributed system in real-time via an observatory-wide EtherCAT network, which is synchronized with high precision to an IEEE 1588 (PTP, Precision Time Protocol) time reference clock. Taking full advantage of the ability of soft-PLCs to run both real-time and non real-time software, the same device also hosts the most important user interfaces (HMIs or Human Machine Interfaces) and communication servers (OPC UA for process data, FTP for XML configuration data, and VNC for remote control). To manage the complexity of the system and to streamline the development process, we show how most of the software, electronics and systems engineering aspects of the control system have been modeled as a set of scripts written in a Domain Specific Language (DSL). When executed, these scripts populate a Knowledge Base (KB) which can be queried to retrieve specific information. By feeding the results of those queries to a template system, we were able to generate very detailed "browsable" web-based documentation about the system, but also PLC software code, Python client code, model verification reports, etc. The aim of this paper is to