WorldWideScience

Sample records for based engineering techniques

  1. 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.

  2. On teaching software engineering based on formal techniques

    DEFF Research Database (Denmark)

    Bjørner, Dines

    2001-01-01

    thoughts about and plans for a different software engineering text book peter Lucas Farewell Symposium......thoughts about and plans for a different software engineering text book peter Lucas Farewell Symposium...

  3. A New Project-Based Curriculum of Design Thinking with Systems Engineering Techniques

    NARCIS (Netherlands)

    Haruyama, S.; Kim, S.K.; Beiter, K.A.; Dijkema, G.P.J.; De Weck, O.L.

    2012-01-01

    We developed a new education curriculum called "ALPS" (Active Learning Project Sequence) at Keio University that emphasizes team project-based learning and design thinking with systems engineering techniques. ALPS is a 6 month course, in which students work as a team and design and propose

  4. Diesel Engine Valve Clearance Fault Diagnosis Based on Features Extraction Techniques and FastICA-SVM

    Science.gov (United States)

    Jing, Ya-Bing; Liu, Chang-Wen; Bi, Feng-Rong; Bi, Xiao-Yang; Wang, Xia; Shao, Kang

    2017-07-01

    Numerous vibration-based techniques are rarely used in diesel engines fault diagnosis in a direct way, due to the surface vibration signals of diesel engines with the complex non-stationary and nonlinear time-varying features. To investigate the fault diagnosis of diesel engines, fractal correlation dimension, wavelet energy and entropy as features reflecting the diesel engine fault fractal and energy characteristics are extracted from the decomposed signals through analyzing vibration acceleration signals derived from the cylinder head in seven different states of valve train. An intelligent fault detector FastICA-SVM is applied for diesel engine fault diagnosis and classification. The results demonstrate that FastICA-SVM achieves higher classification accuracy and makes better generalization performance in small samples recognition. Besides, the fractal correlation dimension and wavelet energy and entropy as the special features of diesel engine vibration signal are considered as input vectors of classifier FastICA-SVM and could produce the excellent classification results. The proposed methodology improves the accuracy of feature extraction and the fault diagnosis of diesel engines.

  5. A DIC Based Technique to Measure the Contraction of a Skeletal Muscle Engineered Tissue

    Directory of Open Access Journals (Sweden)

    Emanuele Rizzuto

    2016-01-01

    Full Text Available Tissue engineering is a multidisciplinary science based on the application of engineering approaches to biologic tissue formation. Engineered tissue internal organization represents a key aspect to increase biofunctionality before transplant and, as regarding skeletal muscles, the potential of generating contractile forces is dependent on the internal fiber organization and is reflected by some macroscopic parameters, such as the spontaneous contraction. Here we propose the application of digital image correlation (DIC as an independent tool for an accurate and noninvasive measurement of engineered muscle tissue spontaneous contraction. To validate the proposed technique we referred to the X-MET, a promising 3-dimensional model of skeletal muscle. The images acquired through a high speed camera were correlated with a custom-made algorithm and the longitudinal strain predictions were employed for measuring the spontaneous contraction. The spontaneous contraction reference values were obtained by studying the force response. The relative error between the spontaneous contraction frequencies computed in both ways was always lower than 0.15%. In conclusion, the use of a DIC based system allows for an accurate and noninvasive measurement of biological tissues’ spontaneous contraction, in addition to the measurement of tissue strain field on any desired region of interest during electrical stimulation.

  6. Manufacturing Techniques and Surface Engineering of Polymer Based Nanoparticles for Targeted Drug Delivery to Cancer

    Directory of Open Access Journals (Sweden)

    Yichao Wang

    2016-02-01

    Full Text Available The evolution of polymer based nanoparticles as a drug delivery carrier via pharmaceutical nano/microencapsulation has greatly promoted the development of nano- and micro-medicine in the past few decades. Poly(lactide-co-glycolide (PLGA and chitosan, which are biodegradable and biocompatible polymers, have been approved by both the Food & Drug Administration (FDA and European Medicine Agency (EMA, making them ideal biomaterials that can be advanced from laboratory development to clinical oral and parental administrations. PLGA and chitosan encapsulated nanoparticles (NPs have successfully been developed as new oral drug delivery systems with demonstrated high efficacy. This review aims to provide a comprehensive overview of the fabrication of PLGA and chitosan particulate systems using nano/microencapsulation methods, the current progress and the future outlooks of the nanoparticulate drug delivery systems. Especially, we focus on the formulations and nano/micro-encapsulation techniques using top-down techniques. It also addresses how the different phases including the organic and aqueous ones in the emulsion system interact with each other and subsequently influence the properties of the drug delivery system. Besides, surface modification strategies which can effectively engineer intrinsic physicochemical properties are summarised. Finally, future perspectives and potential directions of PLGA and chitosan nano/microencapsulated drug systems are outlined.

  7. Low-dose phase-based X-ray imaging techniques for in situ soft tissue engineering assessments.

    Science.gov (United States)

    Izadifar, Zohreh; Honaramooz, Ali; Wiebe, Sheldon; Belev, George; Chen, Xiongbiao; Chapman, Dean

    2016-03-01

    In tissue engineering, non-invasive imaging of biomaterial scaffolds and tissues in living systems is essential to longitudinal animal studies for assessments without interrupting the repair process. Conventional X-ray imaging is inadequate for use in soft tissue engineering due to the limited absorption difference between the soft tissue and biomaterial scaffolds. X-ray phase-based imaging techniques that derive contrast from refraction or phase effects rather than absorption can provide the necessary contrast to see low-density biomaterial scaffolds and tissues in large living systems. This paper explores and compares three synchrotron phase-based X-ray imaging techniques-computed tomography (CT)-diffraction enhanced imaging (DEI), -analyzer based imaging (ABI), and -phase contrast imaging (PCI)-for visualization and characterization of low-density biomaterial scaffolds and tissues in situ for non-invasive soft tissue engineering assessments. Intact pig joints implanted with polycaprolactone scaffolds were used as the model to assess and compare the imaging techniques in terms of different qualitative and quantitative criteria. For long-term in vivo live animal imaging, different strategies for reducing the imaging radiation dose and scan time-reduced number of CT projections, region of interest, and low resolution imaging-were examined with the presented phase-based imaging techniques. The results demonstrated promising capabilities of the phase-based techniques for visualization of biomaterial scaffolds and soft tissues in situ. The low-dose imaging strategies were illustrated effective for reducing the radiation dose to levels appropriate for live animal imaging. The comparison among the imaging techniques suggested that CT-DEI has the highest efficiency in retaining image contrast at considerably low radiation doses. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. In-cylinder pressure-based direct techniques and time frequency analysis for combustion diagnostics in IC engines

    International Nuclear Information System (INIS)

    D’Ambrosio, S.; Ferrari, A.; Galleani, L.

    2015-01-01

    Highlights: • Direct pressure-based techniques have been applied successfully to spark-ignition engines. • The burned mass fraction of pressure-based techniques has been compared with that of 2- and 3-zone combustion models. • The time frequency analysis has been employed to simulate complex diesel combustion events. - Abstract: In-cylinder pressure measurement and analysis has historically been a key tool for off-line combustion diagnosis in internal combustion engines, but online applications for real-time condition monitoring and combustion management have recently become popular. The present investigation presents and compares different low computing-cost in-cylinder pressure based methods for the analyses of the main features of combustion, that is, the start of combustion, the end of combustion and the crankshaft angle that responds to half of the overall burned mass. The instantaneous pressure in the combustion chamber has been used as an input datum for the described analytical procedures and it has been measured by means of a standard piezoelectric transducer. Traditional pressure-based techniques have been shown to be able to predict the burned mass fraction time history more accurately in spark ignition engines than in diesel engines. The most suitable pressure-based techniques for both spark ignition and compression ignition engines have been chosen on the basis of the available experimental data. Time–frequency analysis has also been applied to the analysis of diesel combustion, which is richer in events than spark ignited combustion. Time frequency algorithms for the calculation of the mean instantaneous frequency are computationally efficient, allow the main events of the diesel combustion to be identified and provide the greatest benefits in the presence of multiple injection events. These algorithms can be optimized and applied to onboard diagnostics tools designed for real control, but can also be used as an advanced validation tool for

  9. A Review of the Piezoelectric Electromechanical Impedance Based Structural Health Monitoring Technique for Engineering Structures

    Directory of Open Access Journals (Sweden)

    Wongi S. Na

    2018-04-01

    Full Text Available The birth of smart materials such as piezoelectric (PZT transducers has aided in revolutionizing the field of structural health monitoring (SHM based on non-destructive testing (NDT methods. While a relatively new NDT method known as the electromechanical (EMI technique has been investigated for more than two decades, there are still various problems that must be solved before it is applied to real structures. The technique, which has a significant potential to contribute to the creation of one of the most effective SHM systems, involves the use of a single PZT for exciting and sensing of the host structure. In this paper, studies applied for the past decade related to the EMI technique have been reviewed to understand its trend. In addition, new concepts and ideas proposed by various authors are also surveyed, and the paper concludes with a discussion of the potential directions for future works.

  10. Development of free-piston Stirling engine performance and optimization codes based on Martini simulation technique

    Science.gov (United States)

    Martini, William R.

    1989-01-01

    A FORTRAN computer code is described that could be used to design and optimize a free-displacer, free-piston Stirling engine similar to the RE-1000 engine made by Sunpower. The code contains options for specifying displacer and power piston motion or for allowing these motions to be calculated by a force balance. The engine load may be a dashpot, inertial compressor, hydraulic pump or linear alternator. Cycle analysis may be done by isothermal analysis or adiabatic analysis. Adiabatic analysis may be done using the Martini moving gas node analysis or the Rios second-order Runge-Kutta analysis. Flow loss and heat loss equations are included. Graphical display of engine motions and pressures and temperatures are included. Programming for optimizing up to 15 independent dimensions is included. Sample performance results are shown for both specified and unconstrained piston motions; these results are shown as generated by each of the two Martini analyses. Two sample optimization searches are shown using specified piston motion isothermal analysis. One is for three adjustable input and one is for four. Also, two optimization searches for calculated piston motion are presented for three and for four adjustable inputs. The effect of leakage is evaluated. Suggestions for further work are given.

  11. An Electronic Engineering Curriculum Design Based on Concept-Mapping Techniques

    Science.gov (United States)

    Toral, S. L.; Martinez-Torres, M. R.; Barrero, F.; Gallardo, S.; Duran, M. J.

    2007-01-01

    Curriculum design is a concern in European Universities as they face the forthcoming European Higher Education Area (EHEA). This process can be eased by the use of scientific tools such as Concept-Mapping Techniques (CMT) that extract and organize the most relevant information from experts' experience using statistics techniques, and helps a…

  12. 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.

  13. Tracer-based laser-induced fluorescence measurement technique for quantitative fuel/air-ratio measurements in a hydrogen internal combustion engine.

    Science.gov (United States)

    Blotevogel, Thomas; Hartmann, Matthias; Rottengruber, Hermann; Leipertz, Alfred

    2008-12-10

    A measurement technique for the quantitative investigation of mixture formation processes in hydrogen internal combustion engines (ICEs) has been developed using tracer-based laser-induced fluorescence (TLIF). This technique can be employed to fired and motored engine operation. The quantitative TLIF fuel/air-ratio results have been verified by means of linear Raman scattering measurements. Exemplary results of the simultaneous investigation of mixture formation and combustion obtained at an optical accessible hydrogen ICE are shown.

  14. 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.

  15. Genome scale engineering techniques for metabolic engineering.

    Science.gov (United States)

    Liu, Rongming; Bassalo, Marcelo C; Zeitoun, Ramsey I; Gill, Ryan T

    2015-11-01

    Metabolic engineering has expanded from a focus on designs requiring a small number of genetic modifications to increasingly complex designs driven by advances in genome-scale engineering technologies. Metabolic engineering has been generally defined by the use of iterative cycles of rational genome modifications, strain analysis and characterization, and a synthesis step that fuels additional hypothesis generation. This cycle mirrors the Design-Build-Test-Learn cycle followed throughout various engineering fields that has recently become a defining aspect of synthetic biology. This review will attempt to summarize recent genome-scale design, build, test, and learn technologies and relate their use to a range of metabolic engineering applications. Copyright © 2015 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  16. Novel development of carbonate apatite-chitosan scaffolds based on lyophilization technique for bone tissue engineering

    Directory of Open Access Journals (Sweden)

    Maretaningtias Dwi Ariani

    2012-09-01

    Full Text Available Background: The natural biopolymer chitosan (Ch is currently regarded as a candidate for bone tissue engineering. However, Ch is poor for cell adhesion and low bone formation ability. In order to enhance cell adhesion and bone formation ability, combination of Ch with carbonate apatite (CA was developed. Purpose: The aim of this study was to make carbonate apatite-chitosan scaffolds (CAChSs and evaluate its osteoconductivity in terms of cell proliferation. Methods: Chitosan scaffolds (ChSs were made by the following procedure. Twenty-five, 50, 100, 200 and 400 mg Ch was dissolved into 5 ml of 2% acetic acid (CH3COOH, shaked for 15 min and neutralized with 15 ml of 0.1 M sodium hydroxide (NaOH solution. After centrifugation, Ch gel was packed into the molds then frozen at -80°C for 2h and dried in a freeze dry machine for 24h. The sponges were subjected to UV radiation for 2h. To make CA-ChSs, 200 mg Ch was selected. After neutralization, 50 mg of 0.06 M CA were added into the 200 mg Ch gel. The structure of CA-ChSs was observed by scanning electron microscope (SEM. Mouse osteoblast-like cell (MC3T3-E1 proliferation in these scaffolds was investigated at 1, 7, 14 and 21 days. Results: Three dimensional porous structures of CA-ChSs were clearly observed by SEM. Proliferated cell numbers in CA-ChSs was significantly higher than those in ChSs (control at each stage (p<0.05. Conclusion: It can be concluded that newly developed CA-ChSs had three-dimensional interconnected porous structure, good handling property and supporting ability of proliferation of osteoblasts. It is suggested that newly developed CA-ChSs could be considered as a scaffolds material for bone tissue enginearing.Latar belakang: Kitosan yang merupakan biopolimer alami dianggap sebagai salah satu kandidat untuk rekayasa jaringan tulang. Namun, kitosan memiliki kelemahan terhadap adhesi sel dan kurang mampu membentuk tulang yang cukup. Untuk meningkatkan adhesi sel dan kemampuan

  17. Soft computing techniques in engineering applications

    CERN Document Server

    Zhong, Baojiang

    2014-01-01

    The Soft Computing techniques, which are based on the information processing of biological systems are now massively used in the area of pattern recognition, making prediction & planning, as well as acting on the environment. Ideally speaking, soft computing is not a subject of homogeneous concepts and techniques; rather, it is an amalgamation of distinct methods that confirms to its guiding principle. At present, the main aim of soft computing is to exploit the tolerance for imprecision and uncertainty to achieve tractability, robustness and low solutions cost. The principal constituents of soft computing techniques are probabilistic reasoning, fuzzy logic, neuro-computing, genetic algorithms, belief networks, chaotic systems, as well as learning theory. This book covers contributions from various authors to demonstrate the use of soft computing techniques in various applications of engineering.  

  18. Fabrication of polyurethane and polyurethane based composite fibres by the electrospinning technique for soft tissue engineering of cardiovascular system.

    Science.gov (United States)

    Kucinska-Lipka, J; Gubanska, I; Janik, H; Sienkiewicz, M

    2015-01-01

    Electrospinning is a unique technique, which provides forming of polymeric scaffolds for soft tissue engineering, which include tissue scaffolds for soft tissues of the cardiovascular system. Such artificial soft tissues of the cardiovascular system may possess mechanical properties comparable to native vascular tissues. Electrospinning technique gives the opportunity to form fibres with nm- to μm-scale in diameter. The arrangement of obtained fibres and their surface determine the biocompatibility of the scaffolds. Polyurethanes (PUs) are being commonly used as a prosthesis of cardiovascular soft tissues due to their excellent biocompatibility, non-toxicity, elasticity and mechanical properties. PUs also possess fine spinning properties. The combination of a variety of PU properties with an electrospinning technique, conducted at the well tailored conditions, gives unlimited possibilities of forming novel polyurethane materials suitable for soft tissue scaffolds applied in cardiovascular tissue engineering. This paper can help researches to gain more widespread and deeper understanding of designing electrospinable PU materials, which may be used as cardiovascular soft tissue scaffolds. In this paper we focus on reagents used in PU synthesis designed to increase PU biocompatibility (polyols) and biodegradability (isocyanates). We also describe suggested surface modifications of electrospun PUs, and the direct influence of surface wettability on providing enhanced biocompatibility of scaffolds. We indicate a great influence of electrospinning parameters (voltage, flow rate, working distance) and used solvents (mostly DMF, THF and HFIP) on fibre alignment and diameter - what impacts the biocompatibility and hemocompatibility of such electrospun PU scaffolds. Moreover, we present PU modifications with natural polymers with novel approach applied in electrospinning of PU scaffolds. This work may contribute with further developing of novel electrospun PUs, which may be

  19. PHBV/PLLA-based composite scaffolds fabricated using an emulsion freezing/freeze-drying technique for bone tissue engineering: surface modification and in vitro biological evaluation

    International Nuclear Information System (INIS)

    Sultana, Naznin; Wang Min

    2012-01-01

    Tissue engineering combines living cells with biodegradable materials and/or bioactive components. Composite scaffolds containing biodegradable polymers and nanosized osteoconductive bioceramic with suitable properties are promising for bone tissue regeneration. In this paper, based on blending two biodegradable and biocompatible polymers, namely poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) and poly(l-lactic acid) (PLLA) with incorporated nano hydroxyapatite (HA), three-dimensional composite scaffolds with controlled microstructures and an interconnected porous structure, together with high porosity, were fabricated using an emulsion freezing/freeze-drying technique. The influence of various parameters involved in the emulsion freezing/freeze-drying technique was studied for the fabrication of good-quality polymer scaffolds based on PHBV polymers. The morphology, mechanical properties and crystallinity of PHBV/PLLA and HA in PHBV/PLLA composite scaffolds and PHBV polymer scaffolds were studied. The scaffolds were coated with collagen in order to improve wettability. During in vitro biological evaluation study, it was observed that SaOS-2 cells had high attachment on collagen-coated scaffolds. Significant improvement in cell proliferation and alkaline phosphatase activity for HA-incorporated composite scaffolds was observed due to the incorporation of HA. After 3 and 7 days of culture on all scaffolds, SaOS-2 cells also had normal morphology and growth. These results indicated that PHBV/PLLA-based scaffolds fabricated via an emulsion freezing/freeze-drying technique were favorable sites for osteoblastic cells and are promising for the applications of bone tissue engineering.

  20. Analyzing Convergence in e-Learning Resource Filtering Based on ACO Techniques: A Case Study with Telecommunication Engineering Students

    Science.gov (United States)

    Munoz-Organero, Mario; Ramirez, Gustavo A.; Merino, Pedro Munoz; Kloos, Carlos Delgado

    2010-01-01

    The use of swarm intelligence techniques in e-learning scenarios provides a way to combine simple interactions of individual students to solve a more complex problem. After getting some data from the interactions of the first students with a central system, the use of these techniques converges to a solution that the rest of the students can…

  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. Development of mechanically expanded gelatin-AAc-PLLA/PLCL nanofibers for vascular tissue engineering by radiation-based techniques

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Jin Oh; Jeong, Sung In; Seo, Da Eun; Park, Jong Seok; Gwon, Hui Jeong; Ahn, Sung Jun; Lim, Youn Mook [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Shin, Young Min [Dept. of Bioengineering, Division of Applied Chemical and Bio Engineering, Hanyang University, Seoul (Korea, Republic of)

    2015-12-15

    Vascular tissue engineering has been accessed to mimic the natural composition of the blood vessel containing inmate, media, and adventitia layers. We fabricated mechanically expanded PLLA/PLCL nanofibers using electrospinning and UTM. The pore size of the meshes was increased the gelatin immobilized AAc-PLLA/PLCL nanofibers (203.30±49.62 microns) than PLLA/PLCL nanofibers (59.99±8.66 microns) after mechanical expansion. To increase the cell adhesion and proliferation, we introduced carboxyl group, and gelatin was conjugated on them. The properties of the PLLA/PLCL nanofibers were analyzed with SEM, ATR-FTIR, TBO staining, and water contact angle measurement, general cell responses on the PLLA/PLCL nanofibers such as adhesion, proliferation, and infiltration were also investigated using smooth muscle cell (SMC). During the SMC culture, the initial viability of the cells was significantly increased on the gelatin immobilized AAc-PLLA/PLCL nanofibers, and infiltration of the cells was also enhanced on them. Therefore, gelatin immobilized AAc-PLLA/PLCL nanofibers and mechanically expanded meshes may be a good tool for vascular tissue engineering application.

  3. Evaluation of the Use of Two Teaching Techniques in Engineering

    Directory of Open Access Journals (Sweden)

    Jose Antonio Alvarez Salas

    2014-06-01

    Full Text Available This paper presents an analysis of the practical implementation of two teaching techniques so-called Problem-Based Learning and Cooperative Learning. These techniques were applied to some courses in the Department of Mechanical and Electrical Engineering and evaluated through assessment rubrics. In a sample of students and teachers, the assessment rubrics were applied to numerically evaluate the proportion of each course, in which the teacher uses traditional teaching versus teaching for meaningful learning. The results of the presented analysis allow to verify the use of these teaching techniques by professors of the Department of Mechanical and Electrical Engineering. This activity was developed as a part of the work established by the Institutional Development Plan of the Faculty of Engineering, which includes the strategic objective of developing an innovative educational model in the following ten years.

  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. Novel injector techniques for coal-fueled diesel engines

    Energy Technology Data Exchange (ETDEWEB)

    Badgley, P.R.

    1992-09-01

    This report, entitled Novel Injector Techniques for Coal-Fueled Diesel Engines,'' describes the progress and findings of a research program aimed at development of a dry coal powder fuel injector in conjunction with the Thermal Ignition Combustion System (TICS) concept to achieve autoignition of dry powdered coal in a single-cylinder high speed diesel engine. The basic program consisted of concept selection, analysis and design, bench testing and single cylinder engine testing. The coal injector concept which was selected was a one moving part dry-coal-powder injector utilizing air blast injection. Adiabatics has had previous experience running high speed diesel engines on both direct injected directed coal-water-slurry (CWS) fuel and also with dry coal powder aspirated into the intake air. The Thermal Ignition Combustion System successfully ignited these fuels at all speeds and loads without requiring auxiliary ignition energy such as pilot diesel fuel, heated intake air or glow or spark plugs. Based upon this prior experience, it was shown that the highest efficiency and fastest combustion was with the dry coal, but that the use of aspiration of coal resulted in excessive coal migration into the engine lubrication system. Based upon a desire of DOE to utilize a more modern test engine, the previous naturally-aspirated Caterpillar model 1Y73 single cylinder engine was replaced with a turbocharged (by use of shop air compressor and back pressure control valve) single cylinder version of the Cummins model 855 engine.

  6. Experimental Technique of Titanium Fire in Aero-engine

    Directory of Open Access Journals (Sweden)

    MI Guangbao

    2016-06-01

    Full Text Available Titanium fire is the typical catastrophic fault in the aero-engine. Aiming at the urgent demand for experimental technique of titanium fire from advanced high thrust-weight ratio aero-engine, the combustion technology and theory of titanium alloy based on friction oxygen concentration method (FOC were systematically studied. The evaluation method of fireproof property and the friction ignition model were built, and the fireproof mechanism was illustrated. By generalizing recent progress in experimental technique of titanium fire from three levels, including evolutionary rule, mechanism and prevention and control technology, the ideas and directions of experimental technique associated with the application research of titanium fire in the future were proposed, namely overall evaluation of fireproof property close to air flow environment of the aero-engine, prediction model of fireproof property and experimental verification of fireproof technique under the air flow environment of aero-engine. It is necessary to establish the prevention system of titanium fire in aero-engine, which contributes to the realization of "full titanium" in compressor and to the increase of high thrust-weight ratio.

  7. Additive manufacturing techniques for the production of tissue engineering constructs.

    Science.gov (United States)

    Mota, Carlos; Puppi, Dario; Chiellini, Federica; Chiellini, Emo

    2015-03-01

    'Additive manufacturing' (AM) refers to a class of manufacturing processes based on the building of a solid object from three-dimensional (3D) model data by joining materials, usually layer upon layer. Among the vast array of techniques developed for the production of tissue-engineering (TE) scaffolds, AM techniques are gaining great interest for their suitability in achieving complex shapes and microstructures with a high degree of automation, good accuracy and reproducibility. In addition, the possibility of rapidly producing tissue-engineered constructs meeting patient's specific requirements, in terms of tissue defect size and geometry as well as autologous biological features, makes them a powerful way of enhancing clinical routine procedures. This paper gives an extensive overview of different AM techniques classes (i.e. stereolithography, selective laser sintering, 3D printing, melt-extrusion-based techniques, solution/slurry extrusion-based techniques, and tissue and organ printing) employed for the development of tissue-engineered constructs made of different materials (i.e. polymeric, ceramic and composite, alone or in combination with bioactive agents), by highlighting their principles and technological solutions. Copyright © 2012 John Wiley & Sons, Ltd.

  8. Intelligent techniques in engineering management theory and applications

    CERN Document Server

    Onar, Sezi

    2015-01-01

    This book presents recently developed intelligent techniques with applications and theory in the area of engineering management. The involved applications of intelligent techniques such as neural networks, fuzzy sets, Tabu search, genetic algorithms, etc. will be useful for engineering managers, postgraduate students, researchers, and lecturers. The book has been written considering the contents of a classical engineering management book but intelligent techniques are used for handling the engineering management problem areas. This comprehensive characteristics of the book makes it an excellent reference for the solution of complex problems of engineering management. The authors of the chapters are well-known researchers with their previous works in the area of engineering management.

  9. Engine control techniques to account for fuel effects

    Science.gov (United States)

    Kumar, Shankar; Frazier, Timothy R.; Stanton, Donald W.; Xu, Yi; Bunting, Bruce G.; Wolf, Leslie R.

    2014-08-26

    A technique for engine control to account for fuel effects including providing an internal combustion engine and a controller to regulate operation thereof, the engine being operable to combust a fuel to produce an exhaust gas; establishing a plurality of fuel property inputs; establishing a plurality of engine performance inputs; generating engine control information as a function of the fuel property inputs and the engine performance inputs; and accessing the engine control information with the controller to regulate at least one engine operating parameter.

  10. Techniques for Analysing Problems in Engineering Projects

    DEFF Research Database (Denmark)

    Thorsteinsson, Uffe

    1998-01-01

    Description of how CPM network can be used for analysing complex problems in engineering projects.......Description of how CPM network can be used for analysing complex problems in engineering projects....

  11. Decomposition techniques in mathematical programming engineering and science applications

    CERN Document Server

    Conejo, Antonio J; Minguez, Roberto; Garcia-Bertrand, Raquel

    2006-01-01

    Optimization plainly dominates the design, planning, operation, and c- trol of engineering systems. This is a book on optimization that considers particular cases of optimization problems, those with a decomposable str- ture that can be advantageously exploited. Those decomposable optimization problems are ubiquitous in engineering and science applications. The book considers problems with both complicating constraints and complicating va- ables, and analyzes linear and nonlinear problems, with and without in- ger variables. The decomposition techniques analyzed include Dantzig-Wolfe, Benders, Lagrangian relaxation, Augmented Lagrangian decomposition, and others. Heuristic techniques are also considered. Additionally, a comprehensive sensitivity analysis for characterizing the solution of optimization problems is carried out. This material is particularly novel and of high practical interest. This book is built based on many clarifying, illustrative, and compu- tional examples, which facilitate the learning p...

  12. Statistical Techniques in Electrical and Computer Engineering

    Indian Academy of Sciences (India)

    Stochastic models and statistical inference from them have been popular methodologies in a variety of engineering disciplines, notably in electrical and computer engineering. Recent years have seen explosive growth in this area, driven by technological imperatives. These now go well beyond their traditional domain of ...

  13. [Advanced online search techniques and dedicated search engines for physicians].

    Science.gov (United States)

    Nahum, Yoav

    2008-02-01

    In recent years search engines have become an essential tool in the work of physicians. This article will review advanced search techniques from the world of information specialists, as well as some advanced search engine operators that may help physicians improve their online search capabilities, and maximize the yield of their searches. This article also reviews popular dedicated scientific and biomedical literature search engines.

  14. In Situ Characterization Techniques Based on Synchrotron Radiation and Neutrons Applied for the Development of an Engineering Intermetallic Titanium Aluminide Alloy

    Directory of Open Access Journals (Sweden)

    Petra Erdely

    2016-01-01

    Full Text Available Challenging issues concerning energy efficiency and environmental politics require novel approaches to materials design. A recent example with regard to structural materials is the emergence of lightweight intermetallic TiAl alloys. Their excellent high-temperature mechanical properties, low density and high stiffness constitute a profile perfectly suitable for their application as advanced aero-engine turbine blades or as turbocharger turbine wheels in next-generation automotive engines. As the properties of TiAl alloys during processing as well as during service are dependent on the phases occurring, detailed knowledge of their volume fractions and distribution within the microstructure is of paramount importance. Furthermore, the behavior of the individual phases during hot deformation and subsequent heat treatments is of interest to define reliable and cost-effective industrial production processes. In situ high-energy X-ray diffraction methods allow tracing the evolution of phase fractions over a large temperature range. Neutron diffraction unveils information on order-disorder transformations in TiAl alloys. Small-angle scattering experiments offer insights into the materials’ precipitation behavior. This review attempts to shine a light on selected in situ diffraction and scattering techniques and the ways in which they promoted the development of an advanced engineering TiAl alloy.

  15. Bone tissue engineering scaffolding: computer-aided scaffolding techniques.

    Science.gov (United States)

    Thavornyutikarn, Boonlom; Chantarapanich, Nattapon; Sitthiseripratip, Kriskrai; Thouas, George A; Chen, Qizhi

    Tissue engineering is essentially a technique for imitating nature. Natural tissues consist of three components: cells, signalling systems (e.g. growth factors) and extracellular matrix (ECM). The ECM forms a scaffold for its cells. Hence, the engineered tissue construct is an artificial scaffold populated with living cells and signalling molecules. A huge effort has been invested in bone tissue engineering, in which a highly porous scaffold plays a critical role in guiding bone and vascular tissue growth and regeneration in three dimensions. In the last two decades, numerous scaffolding techniques have been developed to fabricate highly interconnective, porous scaffolds for bone tissue engineering applications. This review provides an update on the progress of foaming technology of biomaterials, with a special attention being focused on computer-aided manufacturing (Andrade et al. 2002) techniques. This article starts with a brief introduction of tissue engineering (Bone tissue engineering and scaffolds) and scaffolding materials (Biomaterials used in bone tissue engineering). After a brief reviews on conventional scaffolding techniques (Conventional scaffolding techniques), a number of CAM techniques are reviewed in great detail. For each technique, the structure and mechanical integrity of fabricated scaffolds are discussed in detail. Finally, the advantaged and disadvantage of these techniques are compared (Comparison of scaffolding techniques) and summarised (Summary).

  16. High frequency techniques an introduction to RF and microwave engineering

    CERN Document Server

    White, Joseph F

    2004-01-01

    A practical guide for today's wireless engineerHigh Frequency Techniques: An Introduction to RF and Microwave Engineering is a clearly written classical circuit and field theory text illustrated with modern computer simulation software. The book's ten chapters cover: *The origins and current uses of wireless transmission *A review of AC analysis, Kirchhoff's laws, RLC elements, skin effect, and introduction to the use of computer simulation software*Resonators, Q definitions, and Q-based impedance matching *Transmission lines, waves, VSWR, reflection phenomena, Fano's reflection bandwidth limits, telegrapher, and impedance transformation equations*Development and in-depth use of the Smith Chart *Matrix algebra with Z, Y, ABCD, S, and T matrix applications*An unusually thorough introduction to electromagnetic field theory, step-by-step development of vector calculus, Maxwell's equations, waveguides, propagation, and antennas*Backward wave, branch line, rat race and Wilkinson couplers, impedance measurements, a...

  17. 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.

  18. [Development of computer aided forming techniques in manufacturing scaffolds for bone tissue engineering].

    Science.gov (United States)

    Wei, Xuelei; Dong, Fuhui

    2011-12-01

    To review recent advance in the research and application of computer aided forming techniques for constructing bone tissue engineering scaffolds. The literature concerning computer aided forming techniques for constructing bone tissue engineering scaffolds in recent years was reviewed extensively and summarized. Several studies over last decade have focused on computer aided forming techniques for bone scaffold construction using various scaffold materials, which is based on computer aided design (CAD) and bone scaffold rapid prototyping (RP). CAD include medical CAD, STL, and reverse design. Reverse design can fully simulate normal bone tissue and could be very useful for the CAD. RP techniques include fused deposition modeling, three dimensional printing, selected laser sintering, three dimensional bioplotting, and low-temperature deposition manufacturing. These techniques provide a new way to construct bone tissue engineering scaffolds with complex internal structures. With rapid development of molding and forming techniques, computer aided forming techniques are expected to provide ideal bone tissue engineering scaffolds.

  19. On Industrial Use of Requirements Engineering Techniques

    DEFF Research Database (Denmark)

    Bækgaard, Lars; Bæk Jørgensen, Jens; Bisgaard Lassen, Kristian

    2007-01-01

    The basis for this paper is a workshop, which was organised by the first and second author, together with colleagues, and held in February 2007. The theme of the workshop was "requirements engineering for innovative administrative systems". The workshop participants came from software companies......, which are suppliers of administrative systems and organisations, which are users of administrative systems. The result of the workshop was a number of research questions that the participants saw as important to address further. To get started with that, two pilot projects were initiated. The first...... project is about application of the requirements engineering approach called Executable Use Cases in the development of a certain IT system for the Public Utilities in Aalborg, Denmark. The second project is about application of the analysis approach called Activity Cases for a public library in Vejle...

  20. Partial differential equations mathematical techniques for engineers

    CERN Document Server

    Epstein, Marcelo

    2017-01-01

    This monograph presents a graduate-level treatment of partial differential equations (PDEs) for engineers. The book begins with a review of the geometrical interpretation of systems of ODEs, the appearance of PDEs in engineering is motivated by the general form of balance laws in continuum physics. Four chapters are devoted to a detailed treatment of the single first-order PDE, including shock waves and genuinely non-linear models, with applications to traffic design and gas dynamics. The rest of the book deals with second-order equations. In the treatment of hyperbolic equations, geometric arguments are used whenever possible and the analogy with discrete vibrating systems is emphasized. The diffusion and potential equations afford the opportunity of dealing with questions of uniqueness and continuous dependence on the data, the Fourier integral, generalized functions (distributions), Duhamel's principle, Green's functions and Dirichlet and Neumann problems. The target audience primarily comprises graduate s...

  1. Photographic and drafting techniques simplify method of producing engineering drawings

    Science.gov (United States)

    Provisor, H.

    1968-01-01

    Combination of photographic and drafting techniques has been developed to simplify the preparation of three dimensional and dimetric engineering drawings. Conventional photographs can be converted to line drawings by making copy negatives on high contrast film.

  2. Protein engineering techniques gateways to synthetic protein universe

    CERN Document Server

    Poluri, Krishna Mohan

    2017-01-01

    This brief provides a broad overview of protein-engineering research, offering a glimpse of the most common experimental methods. It also presents various computational programs with applications that are widely used in directed evolution, computational and de novo protein design. Further, it sheds light on the advantages and pitfalls of existing methodologies and future perspectives of protein engineering techniques.

  3. Methods and experimental techniques in computer engineering

    CERN Document Server

    Schiaffonati, Viola

    2014-01-01

    Computing and science reveal a synergic relationship. On the one hand, it is widely evident that computing plays an important role in the scientific endeavor. On the other hand, the role of scientific method in computing is getting increasingly important, especially in providing ways to experimentally evaluate the properties of complex computing systems. This book critically presents these issues from a unitary conceptual and methodological perspective by addressing specific case studies at the intersection between computing and science. The book originates from, and collects the experience of, a course for PhD students in Information Engineering held at the Politecnico di Milano. Following the structure of the course, the book features contributions from some researchers who are working at the intersection between computing and science.

  4. Sputtering. [as deposition technique in mechanical engineering

    Science.gov (United States)

    Spalvins, T.

    1976-01-01

    This paper primarily reviews the potential of using the sputtering process as a deposition technique; however, the manufacturing and sputter etching aspects are also discussed. Since sputtering is not regulated by classical thermodynamics, new multicomponent materials can be developed in any possible chemical composition. The basic mechanism for dc and rf sputtering is described. Sputter-deposition is described in terms of the unique advantageous features it offers such as versatility, momentum transfer, stoichiometry, sputter-etching, target geometry (coating complex surfaces), precise controls, flexibility, ecology, and sputtering rates. Sputtered film characteristics, such as strong adherence and coherence and film morphology, are briefly evaluated in terms of varying the sputtering parameters. Also described are some of the specific industrial areas which are turning to sputter-deposition techniques.

  5. 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.

  6. Improved Nanomechanical Test Techniques for Surface Engineered Materials

    Directory of Open Access Journals (Sweden)

    Stephen R. Goodes

    2010-06-01

    Full Text Available The development and implementation of a wide range of innovative nanomechanical test techniques to solve tribological problems in applications as diverse as biomedical and automotive are described in this review. For improved wear resistance and durability, the importance of understanding the system response rather than the coating-only properties is emphasized. There are many applications involving mechanical contact where the key to understanding the problem is to test at higher load and to combine reliable measurements taken across different length scales using both nano- and micro-indentation and related wear measurement techniques which more closely simulate contact conditions to fully understand the mechanical behaviour and hence deliver improved application performance. Results are presented with the NanoTest platform for applications for biomedical devices and surface engineering of lightweight alloys for the automotive industry. By combining results with different techniques it is possible to postulate predictive design rules – based on the elastic and plastic deformation energies involved in contact - to aid the reliable optimisation of mechanical properties in the various contact situations in the different applications.

  7. A Benchmark for Banks’ Strategy in Online Presence – An Innovative Approach Based on Elements of Search Engine Optimization (SEO and Machine Learning Techniques

    Directory of Open Access Journals (Sweden)

    Camelia Elena CIOLAC

    2011-06-01

    Full Text Available This paper aims to offer a new decision tool to assist banks in evaluating their efficiency of Internet presence and in planning the IT investments towards gaining better Internet popularity. The methodology used in this paper goes beyond the simple website interface analysis and uses web crawling as a source for collecting website performance data and employed web technologies and servers. The paper complements this technical perspective with a proposed scorecard used to assess the efforts of banks in Internet presence that reflects the banks’ commitment to Internet as a distribution channel. An innovative approach based on Machine Learning Techniques, the K-Nearest Neighbor Algorithm, is proposed by the author to estimate the Internet Popularity that a bank is likely to achieve based on its size and efforts in Internet presence.

  8. Reliability analysis techniques for the design engineer

    International Nuclear Information System (INIS)

    Corran, E.R.; Witt, H.H.

    1982-01-01

    This paper describes a fault tree analysis package that eliminates most of the housekeeping tasks involved in proceeding from the initial construction of a fault tree to the final stage of presenting a reliability analysis in a safety report. It is suitable for designers with relatively little training in reliability analysis and computer operation. Users can rapidly investigate the reliability implications of various options at the design stage and evolve a system which meets specified reliability objectives. Later independent review is thus unlikely to reveal major shortcomings necessitating modification and project delays. The package operates interactively, allowing the user to concentrate on the creative task of developing the system fault tree, which may be modified and displayed graphically. For preliminary analysis, system data can be derived automatically from a generic data bank. As the analysis proceeds, improved estimates of critical failure rates and test and maintenance schedules can be inserted. The technique is applied to the reliability analysis of the recently upgraded HIFAR Containment Isolation System. (author)

  9. 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...

  10. International Conference on Soft Computing Techniques and Engineering Application

    CERN Document Server

    Li, Xiaolong

    2014-01-01

    The main objective of ICSCTEA 2013 is to provide a platform for researchers, engineers and academicians from all over the world to present their research results and development activities in soft computing techniques and engineering application. This conference provides opportunities for them to exchange new ideas and application experiences face to face, to establish business or research relations and to find global partners for future collaboration.

  11. Positron imaging techniques for process engineering: recent developments at Birmingham

    Science.gov (United States)

    Parker, D. J.; Leadbeater, T. W.; Fan, X.; Hausard, M. N.; Ingram, A.; Yang, Z.

    2008-09-01

    For over 20 years the University of Birmingham has been using positron-emitting radioactive tracers to study engineering processes. The imaging technique of positron emission tomography (PET), widely used for medical applications, has been adapted for these studies, and the complementary technique of positron emission particle tracking (PEPT) has been developed. The radioisotopes are produced using the Birmingham MC40 cyclotron, and a variety of techniques are employed to produce suitable tracers in a wide range of forms. Detectors originally designed for medical use have been modified for engineering applications, allowing measurements to be made on real process equipment, at laboratory or pilot plant scale. This paper briefly reviews the capability of the techniques and introduces a few of the many processes to which they have been applied.

  12. 'Hybrid' non-destructive imaging techniques for engineering materials applications

    OpenAIRE

    2014-01-01

    The combination of X-ray imaging and diffraction techniques provides a unique tool for structural and mechanical analysis of engineering components. A variety of modes can be employed in terms of the spatial resolution (length-scale), time resolution (frequency), and the nature of the physical quantity being interrogated. This thesis describes my contributions towards the development of novel X-ray “rich” imaging experimental techniques and data interpretation. The experiment...

  13. 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...

  14. Neural engineering from advanced biomaterials to 3D fabrication techniques

    CERN Document Server

    Kaplan, David

    2016-01-01

    This book covers the principles of advanced 3D fabrication techniques, stem cells and biomaterials for neural engineering. Renowned contributors cover topics such as neural tissue regeneration, peripheral and central nervous system repair, brain-machine interfaces and in vitro nervous system modeling. Within these areas, focus remains on exciting and emerging technologies such as highly developed neuroprostheses and the communication channels between the brain and prostheses, enabling technologies that are beneficial for development of therapeutic interventions, advanced fabrication techniques such as 3D bioprinting, photolithography, microfluidics, and subtractive fabrication, and the engineering of implantable neural grafts. There is a strong focus on stem cells and 3D bioprinting technologies throughout the book, including working with embryonic, fetal, neonatal, and adult stem cells and a variety of sophisticated 3D bioprinting methods for neural engineering applications. There is also a strong focus on b...

  15. A review of rapid prototyping techniques for tissue engineering purposes

    NARCIS (Netherlands)

    Peltola, Sanna M.; Melchels, Ferry P. W.; Grijpma, Dirk W.; Kellomaki, Minna

    2008-01-01

    Rapid prototyping (RP) is a common name for several techniques, which read in data from computer-aided design (CAD) drawings and manufacture automatically three-dimensional objects layer-by-layer according to the virtual design. The utilization of RP in tissue engineering enables the production of

  16. Evaluation of mass spectrometric techniques for characterization of engineered proteins

    DEFF Research Database (Denmark)

    Roepstorff, P; Schram, K H; Andersen, Jens S.

    1995-01-01

    Mass spectrometric characterization of engineered proteins has been examined using bovine recombinant Acyl-CoA-Binding Protein (rACBP), [15N]-labeled rACBP, and a number of sequence variants of ACBP produced by site-directed mutagenesis. The mass spectrometric techniques include ESIMS and MALDIMS...

  17. The importance of new processing techniques in tissue engineering

    Science.gov (United States)

    Lu, L.; Mikos, A. G.; McIntire, L. V. (Principal Investigator)

    1996-01-01

    The use of polymer scaffolds in tissue engineering is reviewed and processing techniques are examined. The discussion of polymer-scaffold processing explains fiber bonding, solvent casting and particulate leaching, membrane lamination, melt molding, polymer/ceramic fiber composite-foam processing, phase separation, and high-pressure processing.

  18. Metabolic Engineering: Techniques for analysis of targets for genetic manipulations

    DEFF Research Database (Denmark)

    Nielsen, Jens Bredal

    1998-01-01

    enzymes. Despite the prospect of obtaining major improvement through metabolic engineering, this approach is, however, not expected to completely replace the classical approach to strain improvement-random mutagenesis followed by screening. Identification of the optimal genetic changes for improvement......Metabolic engineering has been defined as the purposeful modification of intermediary metabolism using recombinant DNA techniques. With this definition metabolic engineering includes: (1) inserting new pathways in microorganisms with the aim of producing novel metabolites, e.g., production...... of polyketides by Streptomyces; (2) production of heterologous peptides, e.g., production of human insulin, erythropoitin, and tPA; and (3) improvement of both new and existing processes, e.g., production of antibiotics and industrial enzymes. Metabolic engineering is a multidisciplinary approach, which involves...

  19. 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)

  20. The use of creative techniques in the engineering human resources development

    Directory of Open Access Journals (Sweden)

    Pirnau Claudiu

    2017-01-01

    Full Text Available Starting from the role of new technologies in the development of engineering innovation, this paperwork has two main research directions with respect to creativity and innovation in engineering education. These are based on a combination of creative techniques with traditional engineering education methods. The first component of our research presented herein aims the use of creative methods such as Creative Training and Image Streaming, and the second component of the research statistically analyses the Social Media posts regarding the use of Cloud Computing technology as a support for innovation. The aim of combining such lines of research will lead to the emergence of specific knowledge needed to identify and implement new creative techniques in engineering human resources. Applying such creativity techniques within groups of students can result in innovative ideas usable in ongoing research projects, in certain deadlock situations on finding critical solutions to overcome blockages.

  1. Applying decision-making techniques to Civil Engineering Projects

    Directory of Open Access Journals (Sweden)

    Fam F. Abdel-malak

    2017-12-01

    Full Text Available Multi-Criteria Decision-Making (MCDM techniques are found to be useful tools in project managers’ hands to overcome decision-making (DM problems in Civil Engineering Projects (CEPs. The main contribution of this paper includes selecting and studying the popular MCDM techniques that uses different and wide ranges of data types in CEPs. A detailed study including advantages and pitfalls of using the Analytic Hierarchy Process (AHP and Fuzzy Technique for Order of Preference by Similarity to Ideal Solution (Fuzzy TOPSIS is introduced. Those two techniques are selected for the purpose of forming a package that covers most available data types in CEPs. The results indicated that AHP has a structure which simplifies complicated problems, while Fuzzy TOPSIS uses the advantages of linguistic variables to solve the issue of undocumented data and ill-defined problems. Furthermore, AHP is a simple technique that depends on pairwise comparisons of factors and natural attributes, beside it is preferable for widely spread hierarchies. On the other hand, Fuzzy TOPSIS needs more information but works well for the one-tier decision tree as well as it shows more flexibility to work in fuzzy environments. The two techniques have the facility to be integrated and combined in a new module to support most of the decisions required in CEPs. Keywords: Decision-making, AHP, Fuzzy TOPSIS, CBA, Civil Engineering Projects

  2. Monitoring of civil engineering structures using Digital Image Correlation technique

    Directory of Open Access Journals (Sweden)

    Świercz A.

    2010-06-01

    Full Text Available The Digital Image Correlation (DIC technique enables full field, noncontact measurements of displacements and strains of a wide variety of objects. An adaptation of the DIC technique for monitoring of civil-engineering structures is presented in the paper. A general concept of the complex, automatic monitoring system, in which the DIC sensor plays an important role is described. Some new software features, which aim to facilitate outdoor measurements and speed up the correlation analysis, is also introduced. As an example of application, measurements of a railway bridge in Nieporet (Poland are presented. The experimental results are compared with displacements of a FEM model of the bridge.

  3. Bases of technique of sprinting

    Directory of Open Access Journals (Sweden)

    Valeriy Druz

    2015-06-01

    Full Text Available Purpose: to determine the biomechanical consistent patterns of a movement of a body providing the highest speed of sprinting. Material and Methods: the analysis of scientific and methodical literature on the considered problem, the anthropometrical characteristics of the surveyed contingent of sportsmen, the analysis of high-speed shootings of the leading runners of the world. Results: the biomechanical bases of technique of sprinting make dispersal and movement of the general center of body weight of the sportsman on a parabolic curve in a start phase taking into account the initial height of its stay in a pose of a low start. Its further movement happens on a cycloidal trajectory which is formed due to a pendulum movement of the extremities creating the lifting power which provides flight duration more in a running step, than duration of a basic phase. Conclusions: the received biomechanical regularities of technique of sprinting allow increasing the efficiency of training of sportsmen in sprinting.

  4. The influence of production engineering in health care services: a bibliometric study focused on operational techniques

    Directory of Open Access Journals (Sweden)

    Maria Cecília Nascimento Rodrigues

    2016-03-01

    Full Text Available Production Engineering is originated on industrial applications, thereof developed methods and techniques along the last century were influenced by them. However, to the extent that such techniques spillover to non-industrial sectors, interesting opportunities arise. This paper presents a bibliometric study regarding the application of operational techniques that come from Production Engineering areas of study on health care services. The study is based on articles indexed by Scopus database from 2004 to 2014. Data collected was organized in several dimensions such as authors, countries, institutions and publication years and the main particularities were emphasized and discussed. Finally, some opportunities are identified both for the practice in health care units and new research in Production Engineering.

  5. On Formal Methods for Collective Adaptive System Engineering. Scalable Approximated, Spatial Analysis Techniques. Extended Abstract.

    Directory of Open Access Journals (Sweden)

    Diego Latella

    2016-07-01

    Full Text Available In this extended abstract a view on the role of Formal Methods in System Engineering is briefly presented. Then two examples of useful analysis techniques based on solid mathematical theories are discussed as well as the software tools which have been built for supporting such techniques. The first technique is Scalable Approximated Population DTMC Model-checking. The second one is Spatial Model-checking for Closure Spaces. Both techniques have been developed in the context of the EU funded project QUANTICOL.

  6. Database 'catalogue of techniques applied to materials and products of nuclear engineering'

    International Nuclear Information System (INIS)

    Lebedeva, E.E.; Golovanov, V.N.; Podkopayeva, I.A.; Temnoyeva, T.A.

    2002-01-01

    The database 'Catalogue of techniques applied to materials and products of nuclear engineering' (IS MERI) was developed to provide informational support for SSC RF RIAR and other enterprises in scientific investigations. This database contains information on the techniques used at RF Minatom enterprises for reactor material properties investigation. The main purpose of this system consists in the assessment of the current status of the reactor material science experimental base for the further planning of experimental activities and methodical support improvement. (author)

  7. 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.

  8. Artificial intelligence techniques for ground test monitoring of rocket engines

    Science.gov (United States)

    Ali, Moonis; Gupta, U. K.

    1990-01-01

    An expert system is being developed which can detect anomalies in Space Shuttle Main Engine (SSME) sensor data significantly earlier than the redline algorithm currently in use. The training of such an expert system focuses on two approaches which are based on low frequency and high frequency analyses of sensor data. Both approaches are being tested on data from SSME tests and their results compared with the findings of NASA and Rocketdyne experts. Prototype implementations have detected the presence of anomalies earlier than the redline algorithms that are in use currently. It therefore appears that these approaches have the potential of detecting anomalies early eneough to shut down the engine or take other corrective action before severe damage to the engine occurs.

  9. 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.

  10. GIS-based bivariate statistical techniques for groundwater potential ...

    Indian Academy of Sciences (India)

    Ali Haghizadeh

    2017-11-23

    Nov 23, 2017 ... So, these models are known as computational intel- ligence and machine learning techniques to use for replacing physically based models. In contrast, knowledge-driven methods (KDM) use rich prior knowledge for model building based on knowledge engineering and management technologies (Azkune.

  11. Application of classic engineering techniques (value engineering and observational method) at the Weldon Spring Quarry

    International Nuclear Information System (INIS)

    Ferguson, R.D.; Valett, G.L.

    1991-01-01

    In July of 1987 the Weldon Spring quarry was listed on the Environmental Protection Agency National Priority List as the highest priority Federal facility site. The Weldon Spring Site Remedial Action Project applied the principles and techniques of Value Engineering (VE) and the Observational Method to remedial planning efforts at the quarry. VE sessions resulted in modifications of the scenarios developed during the Remedial Investigation/Feasibility Study (RM) process in preparation for conceptual design activities for the removal of waste from the quarry. The Observational Method, a technique developed to manage uncertainties, was used to guide both environmental and engineering planning to ensure that the waste removal activities win be carried out in a safe and environmentally responsible manner

  12. Ultrasound Imaging Techniques for Spatiotemporal Characterization of Composition, Microstructure, and Mechanical Properties in Tissue Engineering.

    Science.gov (United States)

    Deng, Cheri X; Hong, Xiaowei; Stegemann, Jan P

    2016-08-01

    Ultrasound techniques are increasingly being used to quantitatively characterize both native and engineered tissues. This review provides an overview and selected examples of the main techniques used in these applications. Grayscale imaging has been used to characterize extracellular matrix deposition, and quantitative ultrasound imaging based on the integrated backscatter coefficient has been applied to estimating cell concentrations and matrix morphology in tissue engineering. Spectral analysis has been employed to characterize the concentration and spatial distribution of mineral particles in a construct, as well as to monitor mineral deposition by cells over time. Ultrasound techniques have also been used to measure the mechanical properties of native and engineered tissues. Conventional ultrasound elasticity imaging and acoustic radiation force imaging have been applied to detect regions of altered stiffness within tissues. Sonorheometry and monitoring of steady-state excitation and recovery have been used to characterize viscoelastic properties of tissue using a single transducer to both deform and image the sample. Dual-mode ultrasound elastography uses separate ultrasound transducers to produce a more potent deformation force to microscale characterization of viscoelasticity of hydrogel constructs. These ultrasound-based techniques have high potential to impact the field of tissue engineering as they are further developed and their range of applications expands.

  13. A Hybrid Neural Network-Genetic Algorithm Technique for Aircraft Engine Performance Diagnostics

    Science.gov (United States)

    Kobayashi, Takahisa; Simon, Donald L.

    2001-01-01

    In this paper, a model-based diagnostic method, which utilizes Neural Networks and Genetic Algorithms, is investigated. Neural networks are applied to estimate the engine internal health, and Genetic Algorithms are applied for sensor bias detection and estimation. This hybrid approach takes advantage of the nonlinear estimation capability provided by neural networks while improving the robustness to measurement uncertainty through the application of Genetic Algorithms. The hybrid diagnostic technique also has the ability to rank multiple potential solutions for a given set of anomalous sensor measurements in order to reduce false alarms and missed detections. The performance of the hybrid diagnostic technique is evaluated through some case studies derived from a turbofan engine simulation. The results show this approach is promising for reliable diagnostics of aircraft engines.

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

    Science.gov (United States)

    2012-03-01

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

  15. Size Adaptive Region Based Huffman Compression Technique

    OpenAIRE

    Nandi, Utpal; Mandal, Jyotsna Kumar

    2014-01-01

    A loss-less compression technique is proposed which uses a variable length Region formation technique to divide the input file into a number of variable length regions. Huffman codes are obtained for entire file after formation of regions. Symbols of each region are compressed one by one. Comparisons are made among proposed technique, Region Based Huffman compression technique and classical Huffman technique. The proposed technique offers better compression ratio for some files than other two.

  16. Damage characterization in engineering materials using a combination of optical, acoustic, and thermal techniques

    Science.gov (United States)

    Tragazikis, I. K.; Exarchos, D. A.; Dalla, P. T.; Matikas, T. E.

    2016-04-01

    This paper deals with the use of complimentary nondestructive methods for the evaluation of damage in engineering materials. The application of digital image correlation (DIC) to engineering materials is a useful tool for accurate, noncontact strain measurement. DIC is a 2D, full-field optical analysis technique based on gray-value digital images to measure deformation, vibration and strain a vast variety of materials. In addition, this technique can be applied from very small to large testing areas and can be used for various tests such as tensile, torsion and bending under static or dynamic loading. In this study, DIC results are benchmarked with other nondestructive techniques such as acoustic emission for damage localization and fracture mode evaluation, and IR thermography for stress field visualization and assessment. The combined use of these three nondestructive methods enables the characterization and classification of damage in materials and structures.

  17. Identification of the Scale of Changes in Personnel Motivation Techniques at Mechanical-Engineering Enterprises

    Directory of Open Access Journals (Sweden)

    Melnyk Olga G.

    2016-02-01

    Full Text Available The method for identification of the scale of changes in personnel motivation techniques at mechanical-engineering enterprises based on structural and logical sequence of implementation of relevant stages (identification of the mission, strategy and objectives of the enterprise; forecasting the development of the enterprise business environment; SWOT-analysis of actual motivation techniques, deciding on the scale of changes in motivation techniques, choosing providers for changing personnel motivation techniques, choosing an alternative to changing motivation techniques, implementation of changes in motivation techniques; control over changes in motivation techniques. It has been substantiated that the improved method enables providing a systematic and analytical justification for management decisionmaking in this field and choosing the best for the mechanical-engineering enterprise scale and variant of changes in motivation techniques. The method for identification of the scale of changes in motivation techniques at mechanical-engineering enterprises takes into account the previous, current and prospective character. Firstly, the approach is based on considering the past state in the motivational sphere of the mechanical-engineering enterprise; secondly, the method involves identifying the current state of personnel motivation techniques; thirdly, within the method framework the prospective, which is manifested in strategic vision of the enterprise development as well as in forecasting the development of its business environment, is taken into account. The advantage of the proposed method is that the level of its specification may vary depending on the set goals, resource constraints and necessity. Among other things, this method allows integrating various formalized and non-formalized causal relationships in the sphere of personnel motivation at machine-building enterprises and management of relevant processes. This creates preconditions for a

  18. Modal Analysis Based on the Random Decrement Technique

    DEFF Research Database (Denmark)

    Asmussen, J. C.; Brincker, Rune

    1998-01-01

    This article describes the work carried out within the project: Modal Analysis Based on the Random Decrement Technique - Application to Civil Engineering Structures. The project is part of the research programme: Dynamics of Structures sponsored by the Danish Technical Research Counsil. The planned...

  19. Development and application of laser techniques for studying fuel dynamics and NO formation in engines

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Oeivind

    2000-11-01

    In this work a number of laser techniques have been applied in new ways for combustion diagnostics in engines. The applications cover small two-stroke engines, ordinary spark ignition (SI) engines, direct-injection spark ignition (DISI) engines, and heavy-duty diesel truck engines. In an investigation of unmodified two-stroke engines running at high engine speed, it has been shown that cycle-resolved laser diagnostics are applicable to real-world engines. The emission of unburned fuel was detected at the exhaust port with successful discrimination against other unburned hydrocarbons. Although a few problems remain to be solved in order to get quantitative concentration data, valuable information can nonetheless be attained using this technique. The technique would benefit from the use of a non-fluorescing lubricant, as that would decrease the background fluorescence. Laser-based techniques also provide a useful tool for studying the fuel dynamics inside the cylinder. In the development of DISI engines it is of particular importance to acquire knowledge about the distribution of fuel around the spark plug. Numerical computer codes are often used as design tools in these applications. Laser techniques are capable of yielding instantaneous multi-point concentration information with high spatial and temporal resolution, making them ideal both for validation of CFD simulations and for testing designs. The feasibility of using laser diagnostics in the development of DISI engines has been shown. Future research should be aimed at simplifying the procedure for quantifying the data, since a fairly simple and reliable technique would be an important asset for the industry. In a more fundamental study, it has been shown that it is possible to simultaneously detect a substance in both liquid and vapour phase. Water was used in the study since it is easily produced in both phases. Liquid drops were detected using spontaneous Raman scattering, whereas the vapour surrounding them

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

    CERN Document Server

    Papajorgji, Petraq J

    2014-01-01

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

  1. 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

  2. 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

  3. 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.

  4. Autonomous Robotic Following Using Vision Based Techniques

    National Research Council Canada - National Science Library

    Kania, Robert T; Frederick, Phil A; Del Rose, Mike

    2006-01-01

    .... ISAAC is designed to follow a specific person using solely vision based techniques. The core of the vision based algorithms used in this application is based on years of research from a collaboration of government and university partners...

  5. Autonomous Robotic Following Using Vision Based Techniques

    National Research Council Canada - National Science Library

    Kania, Robert T; Del Rose, Michael

    2005-01-01

    .... ISAAC is designed to follow a specific person using solely vision based techniques. The core of the vision based algorithms used in this application is based on years of research from a collaboration of government and university partners...

  6. Introduction to digital instrumentation and control techniques used in nuclear engineering

    International Nuclear Information System (INIS)

    Kurilla, R.G.; Kenney, E.S.

    1988-01-01

    For the past 8 yr, the nuclear engineering department at Pennsylvania State University has been teaching a digital interfacing class at the undergraduate (senior) level. With the ever-increasing use of computers in the nuclear engineering area (such as in the use of automated data acquisition systems) and the complexity of control instrumentation, more than a cursory introduction into electronics and computer controls is needed. Because of the ever-increasing popularity, and hence importance, of IBM-PC compatible microcomputers in the engineering fields, the program has been adapted to the Intel 8086 microprocessor. Courses such as this one are helpful in ensuring the students have an adequate design and practice base as required by accrediting groups. The course, is composed of three parts: (1) machine code/assembly language, (2) interfacing, and (3) final project. Experience demonstrates that a course of this inherent complexity can successfully be taught within a nuclear engineering curriculum without extensive prerequisites. The important ingredient is to treat nuclear engineering students for exactly what they are, engineers. By having them use their creativity and adaptability, they can successfully integrate the digital interfacing techniques now routinely used in the nuclear industry

  7. Application of value engineering technique in construction project

    International Nuclear Information System (INIS)

    Chen Changbing

    2003-01-01

    The author introduces how to apply the theories and methods of the value engineering in construction project. In the construction of a test device of the thermal hydrodynamic process, the authors have greatly reduced the construction cost and shortened the construction period by using the value engineering analyzing method. The application of value engineering in the project management is innovative. This practice indicates that the value engineering is important in many construction projects

  8. Creating tissues from textiles: scalable nonwoven manufacturing techniques for fabrication of tissue engineering scaffolds.

    Science.gov (United States)

    Tuin, S A; Pourdeyhimi, B; Loboa, E G

    2016-02-23

    Electrospun nonwovens have been used extensively for tissue engineering applications due to their inherent similarities with respect to fibre size and morphology to that of native extracellular matrix (ECM). However, fabrication of large scaffold constructs is time consuming, may require harsh organic solvents, and often results in mechanical properties inferior to the tissue being treated. In order to translate nonwoven based tissue engineering scaffold strategies to clinical use, a high throughput, repeatable, scalable, and economic manufacturing process is needed. We suggest that nonwoven industry standard high throughput manufacturing techniques (meltblowing, spunbond, and carding) can meet this need. In this study, meltblown, spunbond and carded poly(lactic acid) (PLA) nonwovens were evaluated as tissue engineering scaffolds using human adipose derived stem cells (hASC) and compared to electrospun nonwovens. Scaffolds were seeded with hASC and viability, proliferation, and differentiation were evaluated over the course of 3 weeks. We found that nonwovens manufactured via these industry standard, commercially relevant manufacturing techniques were capable of supporting hASC attachment, proliferation, and both adipogenic and osteogenic differentiation of hASC, making them promising candidates for commercialization and translation of nonwoven scaffold based tissue engineering strategies.

  9. Practical Applications of Evolutionary Computation to Financial Engineering Robust Techniques for Forecasting, Trading and Hedging

    CERN Document Server

    Iba, Hitoshi

    2012-01-01

    “Practical Applications of Evolutionary Computation to Financial Engineering” presents the state of the art techniques in Financial Engineering using recent results in Machine Learning and Evolutionary Computation. This book bridges the gap between academics in computer science and traders and explains the basic ideas of the proposed systems and the financial problems in ways that can be understood by readers without previous knowledge on either of the fields. To cement the ideas discussed in the book, software packages are offered that implement the systems described within. The book is structured so that each chapter can be read independently from the others. Chapters 1 and 2 describe evolutionary computation. The third chapter is an introduction to financial engineering problems for readers who are unfamiliar with this area. The following chapters each deal, in turn, with a different problem in the financial engineering field describing each problem in detail and focusing on solutions based on evolutio...

  10. Microprocessor based techniques at CESR

    International Nuclear Information System (INIS)

    Giannini, G.; Cornell Univ., Ithaca, NY

    1981-01-01

    Microprocessor based systems succesfully used in connection with the High Energy Physics experimental program at the Cornell Electron Storage Ring are described. The multiprocessor calibration system for the CUSB calorimeter is analyzed in view of present and future applications. (orig.)

  11. 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)

  12. Bases en technique du vide

    CERN Document Server

    Rommel, Guy

    2017-01-01

    Cette seconde édition, 20 ans après la première, devrait continuer à aider les techniciens pour la réalisation de leur système de vide. La technologie du vide est utilisée, à présent, dans de nombreux domaines très différents les uns des autres et avec des matériels très fiables. Or, elle est souvent bien peu étudiée, de plus, c'est une discipline où le savoir-faire prend tout son sens. Malheureusement la transmission par des ingénieurs et techniciens expérimentés ne se fait plus ou trop rapidement. La technologie du vide fait appel à la physique, à la chimie, à la mécanique, à la métallurgie, au dessin industriel, à l'électronique, à la thermique, etc. Cette discipline demande donc de maîtriser des techniques de domaines très divers, et ce n'est pas chose facile. Chaque installation est en soi un cas particulier avec ses besoins, sa façon de traiter les matériaux et celle d'utiliser les matériels. Les systèmes de vide sont parfois copiés d'un laboratoire à un autre et le...

  13. Development of optical techniques for chemical engineering applications

    Energy Technology Data Exchange (ETDEWEB)

    Lamadie, F.; Charton, S.; Langlard, M. de; Ouattara, M.; Sentis, M. [CEA, Centre de Marcoule, DEN,DTEC,SGCS, F-30207 Marcoule (France)

    2016-07-01

    The design of separation processes for nuclear spend fuel treatment, dedicated to either research studies or industrial applications, is currently based on a phenomenological approach, relying on Computational Fluid Dynamics, and complemented by validation tests performed at small-scale. Indeed, most of the steps of the Purex process involve multiphasic flows (dissolution, leaching, liquid-liquid extraction, precipitation, filtration, etc.). Therefore an accurate knowledge of the dispersed phase properties is required in order to assess their coupling with the flow features, to predict the process performance and efficiency and to achieve size reduction or extrapolation. Hence, the measurements of particulate flows properties, and especially the particles (or drops or bubbles) size distribution, concentration (i.e. hold-up) and velocity has become a growing issue. Relevant techniques for measuring these flow properties are multiple, from the high-speed video acquisition coupled to image processing to the laser-induced fluorescence, including the particle imaging velocimetry or interferometric techniques (digital in-line holography, rainbow refractometry, etc.). In this communication, different techniques developed at CEA Marcoule for the characterization of multiphase flows, will be introduced. The strong interaction with computational fluid dynamics, in the scope of a multi-scale approach, will be discussed through typical results of gas-liquid, liquid-liquid and solid-liquid flows possibly encountered in nuclear fuel reprocessing process. (authors)

  14. 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...

  15. 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

  16. Application of integrated logistic techniques to operation, maintenance and re engineering processes in Nuclear Power plants

    International Nuclear Information System (INIS)

    Santiago Diez, P.

    1997-01-01

    This paper addresses the advisability of adapting and applying management and Integrated Logistic engineering techniques to nuclear power plants instead of using more traditional maintenance management methods. It establishes a historical framework showing the origins of integrated approaches based on traditional logistic support concepts, their phases and the real results obtained in the aeronautic world where they originated. It reviews the application of integrated management philosophy, and logistic support and engineering analysis techniques regarding Availability, Reliability and Maintainability (ARM) and shows their inter dependencies in different phases of the system's life (Design, Development and Operation). It describes how these techniques are applied to nuclear power plant operation, their impact on plant availability and the optimisation of maintenance and replacement plans. The paper analyses the need for data (type and volume), which will have to be collected, and the different tools to manage such data. It examines the different CALS tools developed by EA for engineering and for logistic management. It also explains the possibility of using these tools for process and data operations through the INTERNET. It also focuses on the qualities of some simple examples of possible applications, and how they would be used in the framework of Integrated Logistic Support (ILS). (Author)

  17. Vibro-acoustic condition monitoring of Internal Combustion Engines: A critical review of existing techniques

    Science.gov (United States)

    Delvecchio, S.; Bonfiglio, P.; Pompoli, F.

    2018-01-01

    This paper deals with the state-of-the-art strategies and techniques based on vibro-acoustic signals that can monitor and diagnose malfunctions in Internal Combustion Engines (ICEs) under both test bench and vehicle operating conditions. Over recent years, several authors have summarized what is known in critical reviews mainly focused on reciprocating machines in general or on specific signal processing techniques: no attempts to deal with IC engine condition monitoring have been made. This paper first gives a brief summary of the generation of sound and vibration in ICEs in order to place further discussion on fault vibro-acoustic diagnosis in context. An overview of the monitoring and diagnostic techniques described in literature using both vibration and acoustic signals is also provided. Different faulty conditions are described which affect combustion, mechanics and the aerodynamics of ICEs. The importance of measuring acoustic signals, as opposed to vibration signals, is due since the former seem to be more suitable for implementation on on-board monitoring systems in view of their non-intrusive behaviour, capability in simultaneously capturing signatures from several mechanical components and because of the possibility of detecting faults affecting airborne transmission paths. In view of the recent needs of the industry to (-) optimize component structural durability adopting long-life cycles, (-) verify the engine final status at the end of the assembly line and (-) reduce the maintenance costs monitoring the ICE life during vehicle operations, monitoring and diagnosing system requests are continuously growing up. The present review can be considered a useful guideline for test engineers in understanding which types of fault can be diagnosed by using vibro-acoustic signals in sufficient time in both test bench and operating conditions and which transducer and signal processing technique (of which the essential background theory is here reported) could be

  18. 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...

  19. Genetic engineering possibilities for CELSS: A bibliography and summary of techniques

    Science.gov (United States)

    Johnson, E. J.

    1982-01-01

    A bibliography of the most useful techniques employed in genetic engineering of higher plants, bacteria associated with plants, and plant cell cultures is provided. A resume of state-of-the-art genetic engineering of plants and bacteria is presented. The potential application of plant bacterial genetic engineering to CELSS (Controlled Ecological Life Support System) program and future research needs are discussed.

  20. A Literature Review of Indexing and Searching Techniques Implementation in Educational Search Engines

    Science.gov (United States)

    El Guemmat, Kamal; Ouahabi, Sara

    2018-01-01

    The objective of this article is to analyze the searching and indexing techniques of educational search engines' implementation while treating future challenges. Educational search engines could greatly help in the effectiveness of e-learning if used correctly. However, these engines have several gaps which influence the performance of e-learning…

  1. 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...

  2. 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

  3. 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)

  4. Determining Engineering Properties of the Shallow Lunar Subsurface using Seismic Surface Wave Techniques

    Science.gov (United States)

    Yeluru, P. M.; Baker, G. S.

    2008-12-01

    The geology of Earth's moon has previously been examined via telescopic observations, orbiting spacecraft readings, lunar sample analysis, and also from some geophysical data. Previous researchers have examined layering of the moon and models exist explaining the velocity variations in the mantle and core. However, no studies (or datasets) currently exist regarding the engineering properties of the shallow (channel Analysis of Surface Wave (MASW), has greatly increased our ability to map subsurface variations in physical properties. The MASW method involves deployment of multiple seismometers to acquire 1-D or 2-D shear wave velocity profiles that can be directly related to various engineering properties. The advantage of this technique over drilling boreholes or any other geophysical technique is that it is less intensive, non-invasive, more cost- effective, and more robust because strong surface-wave records are almost guaranteed. In addition, data processing and analysis is fairly straightforward, and the MASW method allows for analysis of a large area of interest as compared to drilling boreholes. A new scheme using randomly distributed geophones (likely deployed from a mortar-type device) instead of a conventional linear array will be presented. A random array is necessary for lunar exploration because of the logistical constraints involved in deploying a linear or circular array robotically or by astronaut. Initial results indicate that robust dispersion curves (and thus subsurface models of engineering properties) can be obtained from the random array geometry. This random geometry will also be evaluated (a) for potential improvements in the resolution of the dispersion image and (b) as more accurate method for assessing azimuthal variations in the subsurface geology. Based on the extreme logistics imposed by lunar exploration and the anticipated engineering needs of lunar exploration, information obtained on the moon using this technique should prove to be

  5. Knowledge based systems advanced concepts, techniques and applications

    CERN Document Server

    1997-01-01

    The field of knowledge-based systems (KBS) has expanded enormously during the last years, and many important techniques and tools are currently available. Applications of KBS range from medicine to engineering and aerospace.This book provides a selected set of state-of-the-art contributions that present advanced techniques, tools and applications. These contributions have been prepared by a group of eminent researchers and professionals in the field.The theoretical topics covered include: knowledge acquisition, machine learning, genetic algorithms, knowledge management and processing under unc

  6. 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.

  7. 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...

  8. Exploring Arduino tools and techniques for engineering wizardry

    CERN Document Server

    Blum, Jeremy

    2013-01-01

    Learn to easily build gadgets, gizmos, robots, and more using Arduino Written by Arduino expert Jeremy Blum, this unique book uses the popular Arduino microcontroller platform as an instrument to teach you about topics in electrical engineering, programming, and human-computer interaction. Whether you're a budding hobbyist or an engineer, you'll benefit from the perfectly paced lessons that walk you through useful, artistic, and educational exercises that gradually get more advanced. In addition to specific projects, the book shares best practices in programming and design that

  9. Use of electrical resistivity technique for engineering site investigation

    African Journals Online (AJOL)

    The presence of moderately thick (1.5 – 16.5m) clay has been established in this area; therefore the use of raft foundation and/or any other foundation that is commensurate with civil engineering standard is suggested for high rise structures. Keywords: bedrock integrity, transverse unit resistance, foundation. Global Journal ...

  10. Management Science/Industrial Engineering Techniques to Reduce Food Costs.

    Science.gov (United States)

    Greenberg, Murray

    This paper examines the contributions of Industrial Engineering and Management Science toward reduction in the cost of production and distribution of food. Food processing firms were requested to respond to a questionnaire which asked for examples of their use of various operations research tools and information on the number of operations…

  11. The development of a human-centered object based image retrieval engine

    NARCIS (Netherlands)

    van Rikxoort, Eva M.; Kröse, B.J.A.; van den Broek, Egon; Bos, H.J.; Hendriks, E.A.; Schouten, Theo E.; Heijnsdijk, J.W.J.

    2005-01-01

    The development of a new object-based image retrieval (OBIR) engine is discussed. Its goal was to yield intuitive results for users by using human-based techniques. The engine utilizes a unique and efficient set of 15 features: 11 color categories and 4 texture features, derived from the color

  12. Joint application of non-invasive techniques to characterize the dynamic behaviuor of engineering structures

    Science.gov (United States)

    Gallipoli, M. R.; Perrone, A.; Stabile, T. A.; Ponzo, F. C.; Ditommaso, R.

    2012-04-01

    The systematic monitoring of strategic civil infrastructures such as bridges, large dams or high-rise buildings in order to ensure their structural stability is a strategic issue particularly in earthquake-prone regions. Nevertheless, in areas less exposed to seismic hazard, the monitoring is also an important tool for civil engineers, for instance if they have to deal with structures exposed to heavy operational demands for extended periods of time and whose structural integrity might be in question or at risk. A continuous monitoring of such structures allows the identification of their fundamental response characteristics and the changes of these over time, the latter representing indicators for potential structural degradation. The aim of this paper is the estimation of fundamental dynamic parameters of some civil infrastructures by the joint application of fast executable, non-invasive techniques such as the Ambient Noise Standard Spectral Ratio, and Ground-Based microwave Radar Interferometer techniques. The joint approach combine conventional, non-conventional and innovative techniques in order to set up a non destructive evaluation procedure allowing for a multi-sensing monitoring at a multi-scale and multi-depth levels (i.e. with different degrees of spatial resolution and different subsurface depths). In particular, techniques based on ambient vibration recordings have become a popular tool for characterizing the seismic response and state-of-health of strategic civil infrastructure. The primary advantage of these approaches lies in the fact that no transient earthquake signals or even active excitation of the structure under investigation are required. The microwave interferometry radar technology, it has proven to be a powerful remote sensing tool for vibration measurement of structures, such as bridge, heritage architectural structures, vibrating stay cables, and engineering structures. The main advantage of this radar technique is the possibility to

  13. 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

  14. 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.

  15. 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.

  16. 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

  17. Non-genetic engineering of cells for drug delivery and cell-based therapy.

    Science.gov (United States)

    Wang, Qun; Cheng, Hao; Peng, Haisheng; Zhou, Hao; Li, Peter Y; Langer, Robert

    2015-08-30

    Cell-based therapy is a promising modality to address many unmet medical needs. In addition to genetic engineering, material-based, biochemical, and physical science-based approaches have emerged as novel approaches to modify cells. Non-genetic engineering of cells has been applied in delivering therapeutics to tissues, homing of cells to the bone marrow or inflammatory tissues, cancer imaging, immunotherapy, and remotely controlling cellular functions. This new strategy has unique advantages in disease therapy and is complementary to existing gene-based cell engineering approaches. A better understanding of cellular systems and different engineering methods will allow us to better exploit engineered cells in biomedicine. Here, we review non-genetic cell engineering techniques and applications of engineered cells, discuss the pros and cons of different methods, and provide our perspectives on future research directions. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. 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.

  19. Wing and Engine Sizing by Using the Matching Plot Technique

    Directory of Open Access Journals (Sweden)

    Glīzde Nikolajs

    2017-12-01

    Full Text Available The research focuses on the development of an Unmanned Aircraft System. For design purposes, a rather new design method called Systems Engineering Approach is used. Development of the whole system takes much time and effort. This paper contains a concise description of the research on the preliminary development phase of Unmanned Aircraft System air vehicle. The method was first introduced by NASA and later developed by authors of books on aircraft design used for information purposes for design and are mentioned in references. The obtained results are rather realistic and promising for further design process. The method is simple and understandable, and it should be used more often to make it more steady and reliable.

  20. 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...

  1. 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.

  2. Environmental sensitive road planning and transportation techniques in forest engineering

    Directory of Open Access Journals (Sweden)

    H. Hulusi Acar

    2016-07-01

    Full Text Available Forestry management has activities dealing with technical, economic, social and environmental services. Forestry operations which are carried out on forest areas , an important part of the ecosistem are materialized in open space. This forestry activities on large areas and high sloping generally, include many different techniques. It is needed primarily to the forest road network in terms of forest management. Determining the approriate route in the natural environment, planning and road construction affairs for forest roads which are necessary accessing in forest areas, is also of great importance from an environmental viewpoint as well as technical and economic manner. Forest road planning which can not be changed later and left a permanent mark on the natural environment carries much more importance to the environment especially on sloping land. This is because, it is important choosing correct type of roaf structure, and doing periodic maintenance of the roads. Skidding activities, after wood production, is important in terms of its impact on forest soil and by means of effects on saplings and trees on the releated forest areas.The development of environmental sensitive techniques is difficult, limited or expensive for this wood extraction works which are made more difficult conditons in the sloping terrain. Therefore, especially in using some silvicultural methods wood extraction damages are even greater. In this study; some road planning, road construction and wood extraction techniques which performed by me have been made to examine the environmental aspects. Environment-friendly forest roads and primary transport techniques on the forest ecosystem are briefly explained and discussed in the frame of the environmental aspects.

  3. 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...

  4. 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

  5. Increasing the reliability of ecological models using modern software engineering techniques

    Science.gov (United States)

    Robert M. Scheller; Brian R. Sturtevant; Eric J. Gustafson; Brendan C. Ward; David J. Mladenoff

    2009-01-01

    Modern software development techniques are largely unknown to ecologists. Typically, ecological models and other software tools are developed for limited research purposes, and additional capabilities are added later, usually in an ad hoc manner. Modern software engineering techniques can substantially increase scientific rigor and confidence in ecological models and...

  6. Analytical research using synchrotron radiation based techniques

    International Nuclear Information System (INIS)

    Jha, Shambhu Nath

    2015-01-01

    There are many Synchrotron Radiation (SR) based techniques such as X-ray Absorption Spectroscopy (XAS), X-ray Fluorescence Analysis (XRF), SR-Fourier-transform Infrared (SRFTIR), Hard X-ray Photoelectron Spectroscopy (HAXPS) etc. which are increasingly being employed worldwide in analytical research. With advent of modern synchrotron sources these analytical techniques have been further revitalized and paved ways for new techniques such as microprobe XRF and XAS, FTIR microscopy, Hard X-ray Photoelectron Spectroscopy (HAXPS) etc. The talk will cover mainly two techniques illustrating its capability in analytical research namely XRF and XAS. XRF spectroscopy: XRF spectroscopy is an analytical technique which involves the detection of emitted characteristic X-rays following excitation of the elements within the sample. While electron, particle (protons or alpha particles), or X-ray beams can be employed as the exciting source for this analysis, the use of X-ray beams from a synchrotron source has been instrumental in the advancement of the technique in the area of microprobe XRF imaging and trace level compositional characterisation of any sample. Synchrotron radiation induced X-ray emission spectroscopy, has become competitive with the earlier microprobe and nanoprobe techniques following the advancements in manipulating and detecting these X-rays. There are two important features that contribute to the superb elemental sensitivities of microprobe SR induced XRF: (i) the absence of the continuum (Bremsstrahlung) background radiation that is a feature of spectra obtained from charged particle beams, and (ii) the increased X-ray flux on the sample associated with the use of tunable third generation synchrotron facilities. Detection sensitivities have been reported in the ppb range, with values of 10 -17 g - 10 -14 g (depending on the particular element and matrix). Keeping in mind its demand, a microprobe XRF beamline has been setup by RRCAT at Indus-2 synchrotron

  7. Risk assessment techniques with applicability in marine engineering

    Science.gov (United States)

    Rudenko, E.; Panaitescu, F. V.; Panaitescu, M.

    2015-11-01

    Nowadays risk management is a carefully planned process. The task of risk management is organically woven into the general problem of increasing the efficiency of business. Passive attitude to risk and awareness of its existence are replaced by active management techniques. Risk assessment is one of the most important stages of risk management, since for risk management it is necessary first to analyze and evaluate risk. There are many definitions of this notion but in general case risk assessment refers to the systematic process of identifying the factors and types of risk and their quantitative assessment, i.e. risk analysis methodology combines mutually complementary quantitative and qualitative approaches. Purpose of the work: In this paper we will consider as risk assessment technique Fault Tree analysis (FTA). The objectives are: understand purpose of FTA, understand and apply rules of Boolean algebra, analyse a simple system using FTA, FTA advantages and disadvantages. Research and methodology: The main purpose is to help identify potential causes of system failures before the failures actually occur. We can evaluate the probability of the Top event.The steps of this analize are: the system's examination from Top to Down, the use of symbols to represent events, the use of mathematical tools for critical areas, the use of Fault tree logic diagrams to identify the cause of the Top event. Results: In the finally of study it will be obtained: critical areas, Fault tree logical diagrams and the probability of the Top event. These results can be used for the risk assessment analyses.

  8. 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.

  9. 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.

  10. Smartphone based scalable reverse engineering by digital image correlation

    Science.gov (United States)

    Vidvans, Amey; Basu, Saurabh

    2018-03-01

    There is a need for scalable open source 3D reconstruction systems for reverse engineering. This is because most commercially available reconstruction systems are capital and resource intensive. To address this, a novel reconstruction technique is proposed. The technique involves digital image correlation based characterization of surface speeds followed by normalization with respect to angular speed during rigid body rotational motion of the specimen. Proof of concept of the same is demonstrated and validated using simulation and empirical characterization. Towards this, smart-phone imaging and inexpensive off the shelf components along with those fabricated additively using poly-lactic acid polymer with a standard 3D printer are used. Some sources of error in this reconstruction methodology are discussed. It is seen that high curvatures on the surface suppress accuracy of reconstruction. Reasons behind this are delineated in the nature of the correlation function. Theoretically achievable resolution during smart-phone based 3D reconstruction by digital image correlation is derived.

  11. 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....

  12. 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.

  13. 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...

  14. 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.

  15. Invariant-Based Inverse Engineering of Crane Control Parameters

    Science.gov (United States)

    González-Resines, S.; Guéry-Odelin, D.; Tobalina, A.; Lizuain, I.; Torrontegui, E.; Muga, J. G.

    2017-11-01

    By applying invariant-based inverse engineering in the small-oscillation regime, we design the time dependence of the control parameters of an overhead crane (trolley displacement and rope length) to transport a load between two positions at different heights with minimal final-energy excitation for a microcanonical ensemble of initial conditions. The analogy between ion transport in multisegmented traps or neutral-atom transport in moving optical lattices and load manipulation by cranes opens a route for a useful transfer of techniques among very different fields.

  16. Graph based techniques for tag cloud generation

    DEFF Research Database (Denmark)

    Leginus, Martin; Dolog, Peter; Lage, Ricardo Gomes

    2013-01-01

    Tag cloud is one of the navigation aids for exploring documents. Tag cloud also link documents through the user defined terms. We explore various graph based techniques to improve the tag cloud generation. Moreover, we introduce relevance measures based on underlying data such as ratings...... or citation counts for improved measurement of relevance of tag clouds. We show, that on the given data sets, our approach outperforms the state of the art baseline methods with respect to such relevance by 41 % on Movielens dataset and by 11 % on Bibsonomy data set....

  17. A Typology of Techniques for Motivation of Personnel at Mechanical Engineering Enterprises

    Directory of Open Access Journals (Sweden)

    Melnyk Olga G.

    2015-03-01

    Full Text Available The purpose of the article is to develop a typology of techniques for motivation of personnel at mechanical engineering enterprises providing for systematization of their forms on the basis of a number of the existing features and identified new ones, which are justified by the requirements of today. There has been proved the fragmentary character of developments in this area making it impossible to form basic prerequisites for studying the concept. It has been found that certain features of the typology of methods for motivating employees may also be signs of a typology of techniques for motivation of personnel at enterprises of mechanical engineering industry. Among the current signs of a typology of techniques for motivation of personnel at mechanical engineering enterprises it is proposed to use the following ones: the nature of the impact; results obtained, object of the impact; direction; nature of the objectives; scope of the anticipated changes in the existing motivation system; nature of the needs, at which the techniques are directed. In addition, expediency of introducing new features of the typology, namely: the novelty level (classic and innovative motivation techniques, level of individualization (individual and standard; level of formalization (formalized at the high, medium and low level, source of the need for formation and implementation (the techniques, which necessity is specified by the enterprise, and the techniques, which necessity is specified by the business environment, origin («field» and «office» ones. These results allow forming a holistic view of the diversity of techniques for motivation of personnel at mechanical engineering enterprises as well as reasonable choosing among them their individual types at improving the motivation system. Prospects for further research in this direction should be allocation and systematization of the factors influencing the choice of one or another technique for motivation of

  18. Structural design systems using knowledge-based techniques

    International Nuclear Information System (INIS)

    Orsborn, K.

    1993-01-01

    Engineering information management and the corresponding information systems are of a strategic importance for industrial enterprises. This thesis treats the interdisciplinary field of designing computing systems for structural design and analysis using knowledge-based techniques. Specific conceptual models have been designed for representing the structure and the process of objects and activities in a structural design and analysis domain. In this thesis, it is shown how domain knowledge can be structured along several classification principles in order to reduce complexity and increase flexibility. By increasing the conceptual level of the problem description and representation of the domain knowledge in a declarative form, it is possible to enhance the development, maintenance and use of software for mechanical engineering. This will result in a corresponding increase of the efficiency of the mechanical engineering design process. These ideas together with the rule-based control point out the leverage of declarative knowledge representation within this domain. Used appropriately, a declarative knowledge representation preserves information better, is more problem-oriented and change-tolerant than procedural representations. 74 refs

  19. 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.

  20. The Technique for CFD-Simulation of Fuel Valve from Pneumatic-Hydraulic System of Liquid-Propellant Rocket Engine

    Science.gov (United States)

    Shabliy, L. S.; Malov, D. V.; Bratchinin, D. S.

    2018-01-01

    In the article the description of technique for simulation of valves for pneumatic-hydraulic system of liquid-propellant rocket engine (LPRE) is given. Technique is based on approach of computational hydrodynamics (Computational Fluid Dynamics – CFD). The simulation of a differential valve used in closed circuit LPRE supply pipes of fuel components is performed to show technique abilities. A schematic and operation algorithm of this valve type is described in detail. Also assumptions made in the construction of the geometric model of the hydraulic path of the valve are described in detail. The calculation procedure for determining valve hydraulic characteristics is given. Based on these calculations certain hydraulic characteristics of the valve are given. Some ways of usage of the described simulation technique for research the static and dynamic characteristics of the elements of the pneumatic-hydraulic system of LPRE are proposed.

  1. Analytical Modelling of the Effects of Different Gas Turbine Cooling Techniques on Engine Performance =

    Science.gov (United States)

    Uysal, Selcuk Can

    In this research, MATLAB SimulinkRTM was used to develop a cooled engine model for industrial gas turbines and aero-engines. The model consists of uncooled on-design, mean-line turbomachinery design and a cooled off-design analysis in order to evaluate the engine performance parameters by using operating conditions, polytropic efficiencies, material information and cooling system details. The cooling analysis algorithm involves a 2nd law analysis to calculate losses from the cooling technique applied. The model is used in a sensitivity analysis that evaluates the impacts of variations in metal Biot number, thermal barrier coating Biot number, film cooling effectiveness, internal cooling effectiveness and maximum allowable blade temperature on main engine performance parameters of aero and industrial gas turbine engines. The model is subsequently used to analyze the relative performance impact of employing Anti-Vortex Film Cooling holes (AVH) by means of data obtained for these holes by Detached Eddy Simulation-CFD Techniques that are valid for engine-like turbulence intensity conditions. Cooled blade configurations with AVH and other different external cooling techniques were used in a performance comparison study. (Abstract shortened by ProQuest.).

  2. Planetary-Scale Geospatial Data Analysis Techniques in Google's Earth Engine Platform (Invited)

    Science.gov (United States)

    Hancher, M.

    2013-12-01

    Geoscientists have more and more access to new tools for large-scale computing. With any tool, some tasks are easy and other tasks hard. It is natural to look to new computing platforms to increase the scale and efficiency of existing techniques, but there is a more exiting opportunity to discover and develop a new vocabulary of fundamental analysis idioms that are made easy and effective by these new tools. Google's Earth Engine platform is a cloud computing environment for earth data analysis that combines a public data catalog with a large-scale computational facility optimized for parallel processing of geospatial data. The data catalog includes a nearly complete archive of scenes from Landsat 4, 5, 7, and 8 that have been processed by the USGS, as well as a wide variety of other remotely-sensed and ancillary data products. Earth Engine supports a just-in-time computation model that enables real-time preview during algorithm development and debugging as well as during experimental data analysis and open-ended data exploration. Data processing operations are performed in parallel across many computers in Google's datacenters. The platform automatically handles many traditionally-onerous data management tasks, such as data format conversion, reprojection, resampling, and associating image metadata with pixel data. Early applications of Earth Engine have included the development of Google's global cloud-free fifteen-meter base map and global multi-decadal time-lapse animations, as well as numerous large and small experimental analyses by scientists from a range of academic, government, and non-governmental institutions, working in a wide variety of application areas including forestry, agriculture, urban mapping, and species habitat modeling. Patterns in the successes and failures of these early efforts have begun to emerge, sketching the outlines of a new set of simple and effective approaches to geospatial data analysis.

  3. Influence des engins et techniques de peche sur l'abondance ...

    African Journals Online (AJOL)

    Les indices de nuisance et d'impact des engins et techniques de pêche ainsi que l'abondance relative des espèces ont été calculés en utilisant le logiciel XLSTAT. Une cartographie de ces paramètres a été faite par interpolation linéaire sous le logiciel ArcGis 9.3. Les résultats ont révélé 8 engins et techniques de pêche.

  4. Assessing an Entrepreneurship Education Project in Engineering Studies by Means of Participatory Techniques

    Science.gov (United States)

    Ortiz-Medina, Leovigilda; Fernández-Ahumada, Elvira; Lara-Vélez, Pablo; Garrido-Varo, Ana; Pérez-Marin, Dolores; Guerrero-Ginel, José Emilio

    2014-01-01

    The new imperatives of the knowledge-based society require engineering students to equip themselves with a broad range of skills, among which entrepreneurship plays a critical role. An academic itinerary was designed with the explicit aim of improving the entrepreneurial attitudes of agricultural engineering students in a state university in…

  5. Artificial Intelligence based technique for BTS placement

    International Nuclear Information System (INIS)

    Alenoghena, C O; Emagbetere, J O; 1 Minna (Nigeria))" data-affiliation=" (Department of Telecommunications Engineering, Federal University of Techn.1 Minna (Nigeria))" >Aibinu, A M

    2013-01-01

    The increase of the base transceiver station (BTS) in most urban areas can be traced to the drive by network providers to meet demand for coverage and capacity. In traditional network planning, the final decision of BTS placement is taken by a team of radio planners, this decision is not fool proof against regulatory requirements. In this paper, an intelligent based algorithm for optimal BTS site placement has been proposed. The proposed technique takes into consideration neighbour and regulation considerations objectively while determining cell site. The application will lead to a quantitatively unbiased evaluated decision making process in BTS placement. An experimental data of a 2km by 3km territory was simulated for testing the new algorithm, results obtained show a 100% performance of the neighbour constrained algorithm in BTS placement optimization. Results on the application of GA with neighbourhood constraint indicate that the choices of location can be unbiased and optimization of facility placement for network design can be carried out

  6. 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.

  7. Porous magnesium-based scaffolds for tissue engineering

    International Nuclear Information System (INIS)

    Yazdimamaghani, Mostafa; Razavi, Mehdi; Vashaee, Daryoosh; Moharamzadeh, Keyvan; Boccaccini, Aldo R.; Tayebi, Lobat

    2017-01-01

    Significant amount of research efforts have been dedicated to the development of scaffolds for tissue engineering. Although at present most of the studies are focused on non-load bearing scaffolds, many scaffolds have also been investigated for hard tissue repair. In particular, metallic scaffolds are being studied for hard tissue engineering due to their suitable mechanical properties. Several biocompatible metallic materials such as stainless steels, cobalt alloys, titanium alloys, tantalum, nitinol and magnesium alloys have been commonly employed as implants in orthopedic and dental treatments. They are often used to replace and regenerate the damaged bones or to provide structural support for healing bone defects. Among the common metallic biomaterials, magnesium (Mg) and a number of its alloys are effective because of their mechanical properties close to those of human bone, their natural ionic content that may have important functional roles in physiological systems, and their in vivo biodegradation characteristics in body fluids. Due to such collective properties, Mg based alloys can be employed as biocompatible, bioactive, and biodegradable scaffolds for load-bearing applications. Recently, porous Mg and Mg alloys have been specially suggested as metallic scaffolds for bone tissue engineering. With further optimization of the fabrication techniques, porous Mg is expected to make a promising hard substitute scaffold. The present review covers research conducted on the fabrication techniques, surface modifications, properties and biological characteristics of Mg alloys based scaffolds. Furthermore, the potential applications, challenges and future trends of such degradable metallic scaffolds are discussed in detail. - Highlights: • A porous 3D material provides the required pathways for cells to grow, proliferate, and differentiate • Porous magnesium and Mg alloys could be used as load-bearing scaffolds • Porous magnesium and Mg alloys are good

  8. Metamodels for Computer-Based Engineering Design: Survey and Recommendations

    Science.gov (United States)

    Simpson, Timothy W.; Peplinski, Jesse; Koch, Patrick N.; Allen, Janet K.

    1997-01-01

    The use of statistical techniques to build approximations of expensive computer analysis codes pervades much of todays engineering design. These statistical approximations, or metamodels, are used to replace the actual expensive computer analyses, facilitating multidisciplinary, multiobjective optimization and concept exploration. In this paper we review several of these techniques including design of experiments, response surface methodology, Taguchi methods, neural networks, inductive learning, and kriging. We survey their existing application in engineering design and then address the dangers of applying traditional statistical techniques to approximate deterministic computer analysis codes. We conclude with recommendations for the appropriate use of statistical approximation techniques in given situations and how common pitfalls can be avoided.

  9. 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…

  10. The development of quality management techniques in civil engineering design and site supervision

    International Nuclear Information System (INIS)

    Cowan, A.J.

    1991-01-01

    Quality assurance techniques have developed considerably over the past few years, and in particular the application of Quality Management within a service industry such as civil engineering has evolved into a well developed management control system. James Williamson and Partners were the first members of the Association of Consulting Engineers successfully to achieve third party accreditation with BSI for civil and structural design. The initial system was generated for work on Torness Power Station in the early 1980s, and the firm has, in the last ten years, developed a flexible quality system to effectively control and co-ordinate complex projects. This paper discusses the use of quality assurance (QA) techniques in a civil engineering design office, looking at a few areas where the requirements of BS 5750 and BS 5882 are difficult to interpret. Some observations are also made on the adoption of QA for site supervision. (author)

  11. Cognitive Mapping Techniques: Implications for Research in Engineering and Technology Education

    Science.gov (United States)

    Dixon, Raymond A.; Lammi, Matthew

    2014-01-01

    The primary goal of this paper is to present the theoretical basis and application of two types of cognitive maps, concept map and mind map, and explain how they can be used by educational researchers in engineering design research. Cognitive mapping techniques can be useful to researchers as they study students' problem solving strategies…

  12. 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)

  13. 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.

  14. 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.

  15. A general purpose diagnostic technique for marine diesel engines - Application on the main propulsion and auxiliary diesel units of a marine vessel

    International Nuclear Information System (INIS)

    Lamaris, V.T.; Hountalas, D.T.

    2010-01-01

    Diesel engines are widely used in marine applications (i.e. propulsion and auxiliaries) except from a few cases where gas or steam turbines are used. This is the result of their high efficiency, power concentration and reliability compared to other compatible or alternative power sources. The proper and efficient operation of the engines (main engine and diesel generator units) in marine applications is critical, and therefore techniques or systems that determine engine current condition and detect potential faults are extremely important. Furthermore, it is advantageous when such techniques can be applied on different engine configurations and provide reliable results, because on a vessel usually exist diesel engines of different type, i.e. the main propulsion unit is a large low-speed two-stroke diesel engine while the diesel generators are four-stroke medium or high speed engines. In the present work is described and evaluated for the first time the application of an improved diagnostic technique, developed by the authors, on both the main engine and the auxiliary units of a commercial marine vessel. The diagnostic technique is based on a thermodynamic simulation model. The simulation model embedded in the technique has been modified, namely an existing two-zone model is replaced by a multi-zone one. With this modification it is avoided model constant tuning with the operating conditions. This is extremely important for the diagnostic philosophy of the proposed technique. Using data from engine shop tests, the simulation model is calibrated (i.e. model constants are determined) and the engine reference condition is obtained. The simulation model is then used to estimate the current engine condition, using field measurements (i.e. cylinder pressure measurements, periphery data, etc.). From the results it is revealed that the diagnosis method provides detailed information for the operating condition of both engines and the values of parameters that cannot be

  16. 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

  17. 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.

  18. A novel porous scaffold fabrication technique for epithelial and endothelial tissue engineering.

    Science.gov (United States)

    McHugh, Kevin J; Tao, Sarah L; Saint-Geniez, Magali

    2013-07-01

    Porous scaffolds have the ability to minimize transport barriers for both two- (2D) and three-dimensional tissue engineering. However, current porous scaffolds may be non-ideal for 2D tissues such as epithelium due to inherent fabrication-based characteristics. While 2D tissues require porosity to support molecular transport, pores must be small enough to prevent cell migration into the scaffold in order to avoid non-epithelial tissue architecture and compromised function. Though electrospun meshes are the most popular porous scaffolds used today, their heterogeneous pore size and intense topography may be poorly-suited for epithelium. Porous scaffolds produced using other methods have similar unavoidable limitations, frequently involving insufficient pore resolution and control, which make them incompatible with 2D tissues. In addition, many of these techniques require an entirely new round of process development in order to change material or pore size. Herein we describe "pore casting," a fabrication method that produces flat scaffolds with deterministic pore shape, size, and location that can be easily altered to accommodate new materials or pore dimensions. As proof-of-concept, pore-cast poly(ε-caprolactone) (PCL) scaffolds were fabricated and compared to electrospun PCL in vitro using canine kidney epithelium, human colon epithelium, and human umbilical vein endothelium. All cell types demonstrated improved morphology and function on pore-cast scaffolds, likely due to reduced topography and universally small pore size. These results suggest that pore casting is an attractive option for creating 2D tissue engineering scaffolds, especially when the application may benefit from well-controlled pore size or architecture.

  19. An electrochemical engineering technique to improve the corrosion resistance of some structural materials in lead-alloy coolants

    International Nuclear Information System (INIS)

    Tacica, M.; Andrei, V.; Rusu, O.; Coaca, E.; Minca, M.; Florea, S.; Oncioiu, G.

    2013-01-01

    The goal of this paper is to present some conclusions resulted from the literature studies referring to the materials potential to be used in Lead Fast Reactors (LFR), and the results obtained in the surface engineering field which can be used in our institute in order to obtain materials with appropriate properties for their use in LFR. In this context, the paper presents some preliminary results obtained in Surface Analysis Laboratory of INR Pitesti and research works in progress referring to: controlled modification of AISI 316 L surface by electrochemical plasma treatment (carburization, nitrocarburizings); electrodeposition of some protective thin-films based on Ni and Al obtained from ionic liquids; development of some procedures related to the activities involved in the behaviour evaluation, in LFR specific conditions, for material samples subjected to treatments by surface engineering techniques using the LEad COrrosion TEsting LOop (LECOTELO) test bench. The superficial structures obtained have been characterized by metallographic microscopy, X-Ray Photoemission Spectroscopy (XPS), Electrochemical Impedance Spectroscopy (EIS); the electrochemical techniques were used to evaluate the corrosion behaviour. The preliminary results have shown that the used electrochemical surface engineering techniques are appropriate in order to improve the mechanical properties and corrosion behaviour of AISI 316 L steel. (authors)

  20. 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. .

  1. Application of 2D Electrical Resistivity Imaging Technique for Engineering Site Investigation

    Directory of Open Access Journals (Sweden)

    Asem A. Hassan

    2018-03-01

    Full Text Available Engineering site investigation is crucial to characterize the subsurface soil of proposed construction sites. Application of 2D Electrical Resistivity Imaging ERI technique pro- vides useful information about the subsurface geology and the condition along profiles. In this paper, numerical and field studies using 2D ERI technique were adopted for engineer- ing site investigation purposes. The Wenner-Schlumberger array was implemented along three parallel profiles at the construction site of Diyala University, northeast of Baghdad city, to detect buried utilities (pipes left over in the area. A synthetic resistivity model of a buried pipe was designed to discuss and validate the field results. The 2D ERI sections of the model resolve clearly the buried structure, even with 5% noise level. Interpretation of the field data showed that 2D ERI technique was effective in delineating the buried pipes. The vertical and horizontal sensitivity of the Wenner-Schlumberger array for sub- surface resistivity variations made it possible to determine the position and geometry of the buried structures. The current work demonstrates the usefulness of the ERI technique as a complementary tool for engineering site investigation .

  2. Development of reproductive engineering techniques at the RIKEN BioResource Center.

    Science.gov (United States)

    Ogura, Atsuo

    2017-01-27

    Reproductive engineering techniques are essential for assisted reproduction of animals and generation of genetically modified animals. They may also provide invaluable research models for understanding the mechanisms involved in the developmental and reproductive processes. At the RIKEN BioResource Center (BRC), I have sought to develop new reproductive engineering techniques, especially those related to cryopreservation, microinsemination (sperm injection), nuclear transfer, and generation of new stem cell lines and animals, hoping that they will support the present and future projects at BRC. I also want to combine our techniques with genetic and biochemical analyses to solve important biological questions. We expect that this strategy makes our research more unique and refined by providing deeper insights into the mechanisms that govern the reproductive and developmental systems in mammals. To make this strategy more effective, it is critical to work with experts in different scientific fields. I have enjoyed collaborations with about 100 world-recognized laboratories, and all our collaborations have been successful and fruitful. This review summarizes development of reproductive engineering techniques at BRC during these 15 years.

  3. A Process Engineering Approach to the Development and Integration of Intrusion Detection Techniques

    National Research Council Canada - National Science Library

    Ye, Nong

    2001-01-01

    ...) investigate system-level intrusion detection techniques for the fusion and correlation of local information about intrusions, based on the integration infrastructure for intrusion detection; and (3...

  4. A Process Engineering Approach to the Development and Integration of Intrusion Detection Techniques

    National Research Council Canada - National Science Library

    Ye, Nong

    2002-01-01

    ...) investigate system-level intrusion detection techniques for the fusion and correlation of local information about intrusions, based on the integration infrastructure for intrusion detection; and (3...

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

    Science.gov (United States)

    Dirks, Rob; van Dun, Kees; de Snoo, C Bastiaan; van den Berg, Mark; Lelivelt, Cilia L C; Voermans, William; Woudenberg, Leo; de Wit, Jack P C; Reinink, Kees; Schut, Johan W; van der Zeeuw, Eveline; Vogelaar, Aat; Freymark, Gerald; Gutteling, Evert W; Keppel, Marina N; van Drongelen, Paul; Kieny, Matthieu; Ellul, Philippe; Touraev, Alisher; Ma, Hong; de Jong, Hans; Wijnker, Erik

    2009-12-01

    Reverse breeding (RB) is a novel plant breeding technique designed to directly produce parental lines for any heterozygous plant, one of the most sought after goals in plant breeding. RB generates perfectly complementing homozygous parental lines through engineered meiosis. The method is based on reducing genetic recombination in the selected heterozygote by eliminating meiotic crossing over. Male or female spores obtained from such plants contain combinations of non-recombinant parental chromosomes which can be cultured in vitro to generate homozygous doubled haploid plants (DHs). From these DHs, complementary parents can be selected and used to reconstitute the heterozygote in perpetuity. Since the fixation of unknown heterozygous genotypes is impossible in traditional plant breeding, RB could fundamentally change future plant breeding. In this review, we discuss various other applications of RB, including breeding per chromosome.

  6. Promising iron oxide-based magnetic nanoparticles in biomedical engineering.

    Science.gov (United States)

    Tran, Phuong Ha-Lien; Tran, Thao Truong-Dinh; Vo, Toi Van; Lee, Beom-Jin

    2012-12-01

    For the past few decades biomedical engineering has imprinted its significant impact on the map of science through its wide applications on many other fields. An important example obviously proving this fact is the versatile application of magnetic nanoparticles in theranostics. Due to preferable properties such as biocompatibility, non-toxicity compared to other metal derivations, iron oxide-based magnetic nanoparticles was chosen to be addressed in this review. Aim of this review is to give the readers a whole working window of these magnetic nanoparticles in the current context of science. Thus, preparation of magnetic iron oxide nanoparticles with the so-far techniques, methods of characterizing the nanoparticles as well as their most recent biomedical applications will be stated.

  7. Electro fluido dynamic techniques to design instructive biomaterials for tissue engineering and drug delivery

    Energy Technology Data Exchange (ETDEWEB)

    Guarino, Vincenzo, E-mail: vguarino@unina.it; Altobelli, Rosaria; Cirillo, Valentina; Ambrosio, Luigi [Institute for Polymers, Composites and Biomaterials, Department of Chemical Sciences & Materials Technology, National Research Council of Italy, V.le Kennedy 54, Naples (Italy)

    2015-12-17

    A large variety of processes and tools is continuously investigated to discover new solutions to design instructive materials with controlled chemical, physical and biological properties for tissue engineering and drug delivery. Among them, electro fluido dynamic techniques (EFDTs) are emerging as an interesting strategy, based on highly flexible and low-cost processes, to revisit old biomaterial’s manufacturing approach by utilizing electrostatic forces as the driving force for the fabrication of 3D architectures with controlled physical and chemical functionalities to guide in vitro and in vivo cell activities. By a rational selection of polymer solution properties and process conditions, EFDTs allow to produce fibres and/or particles at micro and/or nanometric size scale which may be variously assembled by tailored experimental setups, thus giving the chance to generate a plethora of different 3D devices able to incorporate biopolymers (i.e., proteins, polysaccharides) or active molecules (e.g., drugs) for different applications. Here, we focus on the optimization of basic EFDTs - namely electrospinning, electrospraying and electrodynamic atomization - to develop active platforms (i.e., monocomponent, protein and drug loaded scaffolds and µ-scaffolds) made of synthetic (PCL, PLGA) or natural (chitosan, alginate) polymers. In particular, we investigate how to set materials and process parameters to impart specific morphological, biochemical or physical cues to trigger all the fundamental cell–biomaterial and cell– cell cross-talking elicited during regenerative processes, in order to reproduce the complex microenvironment of native or pathological tissues.

  8. 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.

  9. Optical Measurement Techniques for Rocket Engine Testing and Component Applications: Digital Image Correlation and Dynamic Photogrammetry

    Science.gov (United States)

    Gradl, Paul

    2016-01-01

    NASA Marshall Space Flight Center (MSFC) has been advancing dynamic optical measurement systems, primarily Digital Image Correlation, for extreme environment rocket engine test applications. The Digital Image Correlation (DIC) technology is used to track local and full field deformations, displacement vectors and local and global strain measurements. This technology has been evaluated at MSFC through lab testing to full scale hotfire engine testing of the J-2X Upper Stage engine at Stennis Space Center. It has been shown to provide reliable measurement data and has replaced many traditional measurement techniques for NASA applications. NASA and AMRDEC have recently signed agreements for NASA to train and transition the technology to applications for missile and helicopter testing. This presentation will provide an overview and progression of the technology, various testing applications at NASA MSFC, overview of Army-NASA test collaborations and application lessons learned about Digital Image Correlation.

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. A Comparative Study of Three Vibration Based Damage Assessment Techniques

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Rytter, A.

    Three different vibration based damage assessment techniques have been compared. One of the techniques uses the ratios between changes in experimentally and theoretically estimated natural frequencies, respectively, to locate a damage. The second technique relies on updating of an FEM based...... on experimentally estimated natural frequencies where the stiffness matrix is given as a function of damage size and location. The last technique is based on neural networks trained with the relative changes in natural frequencies. It has been found that all techniques seems to be useful. Especially, the neural...... networks based technique seems to be very promising....

  15. influence des engins et techniques de peche sur l'abondance ...

    African Journals Online (AJOL)

    ACSS

    17 févr. 2017 ... les deux jours indépendants de prospection. Le processus est répété chaque mois afin de tenir compte de la variabilité spatio-temporelle des variables à mesurer. Ces donnéesde pêche collectées sont relatives aux engins et techniques de pêche et, aux espèces de poissons capturées par les pêcheurs.

  16. Assessing and mitigating risks of engineering programs with lean management techniques

    DEFF Research Database (Denmark)

    Fritz, A.; Oehmen, Josef; Rebentisch, E.

    2014-01-01

    This paper investigates the use of lean management techniques as a risk mitigation approach for large-scale engineering programs. The key research questions are how lean best practices with the highest risk mitigation potential are identified, how the most relevant lean best practices for a speci...... by the Project Management Institute (PMI), that both include Risk Management as a focal activity [MSP 2011, PMI 2013]....

  17. CloudSat system engineering: techniques that point to a future success

    Science.gov (United States)

    Basilio, R. R.; Boain, R. J.; Lam, T.

    2002-01-01

    Over the past three years the CloutSat Project, a NASA Earth System Science Pathfinder mission to provide from space the first global survey of cloud profiles and cloud physical properties, has implemented a successful project system engineering approach. Techniques learned through heuristic reasoning of past project events and professional experience were applied along with select methods recently touted to increase effectiveness without compromising effiency.

  18. Review on Enhanced Heat Transfer Techniques using Modern Technologies for 4S Air Cooled Engines

    Science.gov (United States)

    Ramasubramanian, S.; Bupesh Raja, V. K.

    2017-05-01

    Engine performance is a biggest challenge and a vital area of concern when it comes to automobiles. Researchers across the globe have been working decades together meticulously improvising the performance of engine in terms of efficiency. The durability of the engine components mainly depends on the thermal stress it undergoes over the period of operation. Air cooling of engine is the simplest and most desirous technique that has been adopted for ages. In this regard fins or extended surfaces are employed for effective cooling of the cylinder while in operation. The conductive and convective heat transfer rate from the cylinder to the fins and in turn from the fins to surrounding ambience determines the effective performance of the engine. In this paper an attempt is made to review and summarize the various researches that were conducted on the Fins in terms of profile geometry, number of fins, size, thickness factor, material used etc., and to bring about a long term solution with the modern technologies like nano coatings and nano materials.

  19. Digital Image Correlation Techniques Applied to Large Scale Rocket Engine Testing

    Science.gov (United States)

    Gradl, Paul R.

    2016-01-01

    Rocket engine hot-fire ground testing is necessary to understand component performance, reliability and engine system interactions during development. The J-2X upper stage engine completed a series of developmental hot-fire tests that derived performance of the engine and components, validated analytical models and provided the necessary data to identify where design changes, process improvements and technology development were needed. The J-2X development engines were heavily instrumented to provide the data necessary to support these activities which enabled the team to investigate any anomalies experienced during the test program. This paper describes the development of an optical digital image correlation technique to augment the data provided by traditional strain gauges which are prone to debonding at elevated temperatures and limited to localized measurements. The feasibility of this optical measurement system was demonstrated during full scale hot-fire testing of J-2X, during which a digital image correlation system, incorporating a pair of high speed cameras to measure three-dimensional, real-time displacements and strains was installed and operated under the extreme environments present on the test stand. The camera and facility setup, pre-test calibrations, data collection, hot-fire test data collection and post-test analysis and results are presented in this paper.

  20. Android Application Protection against Static Reverse Engineering based on Multidexing

    Directory of Open Access Journals (Sweden)

    Nak Young Kim

    2016-11-01

    Full Text Available DEX files are executable files of Android applications. Since DEX files are in the format of Java bytecodes, their Java source codes can be easily obtained using static reverse engineering tools. This results in numerous Android application thefts. There are some tools (e.g. bangcle, ijiami, liapp that protect Android applications against static reverse engineering utilizing dynamic code loading. These tools usually encrypt classes.dex in an APK file. When the application is launched, the encrypted classes.dex file is decrypted and dynamically loaded. However, these tools fail to protect multidex APKs, which include more than one DEX files (classes2.dex, classes3.dex, ... to accommodate large-sized execution codes. In this paper, we propose a technique that protects multidex Android applications against static reverse engineering. The technique can encrypt/decrypt multiple DEX files in APK files and dynamically load them. The experimental results show that the proposed technique can effiectively protect multidex APKs.

  1. A NEW RULE-BASED APPROACH FOR COMPUTER CHESS PROGRAMMING USING GP-ARTIFICIAL TECHNIQUES : PECP

    OpenAIRE

    HANEDAN, Y.Güney; SERTBAŞ, Ahmet

    2012-01-01

    In this paper, we use a brand new chess engine programming technique which we name PECP (Positional Evolutionary Chess Programming), that brings the Artificial Intelligence and Genetic Programming approaches together, to construct a chess endgame analyzing engine. Throughout the paper, the technique and the algorithm are discussed in detail. Also,  using PECP, an  example program (RETI V1.0)  aimed to prove the correctness and performance of the rule-based theory and algorithm is written in P...

  2. Hydrogel based approaches for cardiac tissue engineering.

    Science.gov (United States)

    Saludas, Laura; Pascual-Gil, Simon; Prósper, Felipe; Garbayo, Elisa; Blanco-Prieto, María

    2017-05-25

    Heart failure still represents the leading cause of death worldwide. Novel strategies using stem cells and growth factors have been investigated for effective cardiac tissue regeneration and heart function recovery. However, some major challenges limit their translation to the clinic. Recently, biomaterials have emerged as a promising approach to improve delivery and viability of therapeutic cells and proteins for the regeneration of the damaged heart. In particular, hydrogels are considered one of the most promising vehicles. They can be administered through minimally invasive techniques while maintaining all the desirable characteristics of drug delivery systems. This review discusses recent advances made in the field of hydrogels for cardiac tissue regeneration in detail, focusing on the type of hydrogel (conventional, injectable, smart or nano- and micro-gel), the biomaterials used for its manufacture (natural, synthetic or hybrid) and the therapeutic agent encapsulated (stem cells or proteins). We expect that these novel hydrogel-based approaches will open up new possibilities in drug delivery and cell therapies. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. DCT-based cyber defense techniques

    Science.gov (United States)

    Amsalem, Yaron; Puzanov, Anton; Bedinerman, Anton; Kutcher, Maxim; Hadar, Ofer

    2015-09-01

    With the increasing popularity of video streaming services and multimedia sharing via social networks, there is a need to protect the multimedia from malicious use. An attacker may use steganography and watermarking techniques to embed malicious content, in order to attack the end user. Most of the attack algorithms are robust to basic image processing techniques such as filtering, compression, noise addition, etc. Hence, in this article two novel, real-time, defense techniques are proposed: Smart threshold and anomaly correction. Both techniques operate at the DCT domain, and are applicable for JPEG images and H.264 I-Frames. The defense performance was evaluated against a highly robust attack, and the perceptual quality degradation was measured by the well-known PSNR and SSIM quality assessment metrics. A set of defense techniques is suggested for improving the defense efficiency. For the most aggressive attack configuration, the combination of all the defense techniques results in 80% protection against cyber-attacks with PSNR of 25.74 db.

  4. 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.

  5. Nasal base narrowing: the combined alar base excision technique.

    Science.gov (United States)

    Foda, Hossam M T

    2007-01-01

    To evaluate the role of the combined alar base excision technique in narrowing the nasal base and correcting excessive alar flare. The study included 60 cases presenting with a wide nasal base and excessive alar flaring. The surgical procedure combined an external alar wedge resection with an internal vestibular floor excision. All cases were followed up for a mean of 32 (range, 12-144) months. Nasal tip modification and correction of any preexisting caudal septal deformities were always completed before the nasal base narrowing. The mean width of the external alar wedge excised was 7.2 (range, 4-11) mm, whereas the mean width of the sill excision was 3.1 (range, 2-7) mm. Completing the internal excision first resulted in a more conservative external resection, thus avoiding any blunting of the alar-facial crease. No cases of postoperative bleeding, infection, or keloid formation were encountered, and the external alar wedge excision healed with an inconspicuous scar that was well hidden in the depth of the alar-facial crease. Finally, the risk of notching of the alar rim, which can occur at the junction of the external and internal excisions, was significantly reduced by adopting a 2-layered closure of the vestibular floor (P = .01). The combined alar base excision resulted in effective narrowing of the nasal base with elimination of excessive alar flare. Commonly feared complications, such as blunting of the alar-facial crease or notching of the alar rim, were avoided by using simple modifications in the technique of excision and closure.

  6. 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…

  7. 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,…

  8. 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.

  9. Flood alert system based on bayesian techniques

    Science.gov (United States)

    Gulliver, Z.; Herrero, J.; Viesca, C.; Polo, M. J.

    2012-04-01

    The problem of floods in the Mediterranean regions is closely linked to the occurrence of torrential storms in dry regions, where even the water supply relies on adequate water management. Like other Mediterranean basins in Southern Spain, the Guadalhorce River Basin is a medium sized watershed (3856 km2) where recurrent yearly floods occur , mainly in autumn and spring periods, driven by cold front phenomena. The torrential character of the precipitation in such small basins, with a concentration time of less than 12 hours, produces flash flood events with catastrophic effects over the city of Malaga (600000 inhabitants). From this fact arises the need for specific alert tools which can forecast these kinds of phenomena. Bayesian networks (BN) have been emerging in the last decade as a very useful and reliable computational tool for water resources and for the decision making process. The joint use of Artificial Neural Networks (ANN) and BN have served us to recognize and simulate the two different types of hydrological behaviour in the basin: natural and regulated. This led to the establishment of causal relationships between precipitation, discharge from upstream reservoirs, and water levels at a gauging station. It was seen that a recurrent ANN model working at an hourly scale, considering daily precipitation and the two previous hourly values of reservoir discharge and water level, could provide R2 values of 0.86. BN's results slightly improve this fit, but contribute with uncertainty to the prediction. In our current work to Design a Weather Warning Service based on Bayesian techniques the first steps were carried out through an analysis of the correlations between the water level and rainfall at certain representative points in the basin, along with the upstream reservoir discharge. The lower correlation found between precipitation and water level emphasizes the highly regulated condition of the stream. The autocorrelations of the variables were also

  10. 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

    In most cost estimating applications at the NASA Langley Research Center (LaRC), it is desirable to present predicted cost as a range of possible costs rather than a single predicted cost. A cost risk analysis generates a range of cost for a project and assigns a probability level to each cost value in the range. Constructing a cost risk curve requires a good estimate of the expected cost of a project. It must also include a good estimate of expected variance of the cost. Many cost risk analyses are based upon an expert's knowledge of the cost of similar projects in the past. In a common scenario, a manager or engineer, asked to estimate the cost of a project in his area of expertise, will gather historical cost data from a similar completed project. The cost of the completed project is adjusted using the perceived technical and economic differences between the two projects. This allows errors from at least three sources. The historical cost data may be in error by some unknown amount. The managers' evaluation of the new project and its similarity to the old project may be in error. The factors used to adjust the cost of the old project may not correctly reflect the differences. Some risk analyses are based on untested hypotheses about the form of the statistical distribution that underlies the distribution of possible cost. The usual problem is not just to come up with an estimate of the cost of a project, but to predict the range of values into which the cost may fall and with what level of confidence the prediction is made. Risk analysis techniques that assume the shape of the underlying cost distribution and derive the risk curve from a single estimate plus and minus some amount usually fail to take into account the actual magnitude of the uncertainty in cost due to technical factors in the project itself. This paper addresses a cost risk method that is based on parametric estimates of the technical factors involved in the project being costed. The engineering

  11. 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.

  12. 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...

  13. 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

  14. An International Collaboration to Promote Inquiry-Based Learning in Undergraduate Engineering Classrooms

    Science.gov (United States)

    Randall, D'Arcy C.; Moore, Christy; Carvalho, Isabel S.

    2012-01-01

    Purpose: The purpose of this paper is to describe specific techniques of "inquiry-based learning" employed by three instructors in Engineering schools, one in Europe and two in the USA. Design/methodology/approach: Theorists such as Bransford et al. argue that twenty-first century educators need to teach students to do more than simply…

  15. Identifying Engineering Students' English Sentence Reading Comprehension Errors: Applying a Data Mining Technique

    Science.gov (United States)

    Tsai, Yea-Ru; Ouyang, Chen-Sen; Chang, Yukon

    2016-01-01

    The purpose of this study is to propose a diagnostic approach to identify engineering students' English reading comprehension errors. Student data were collected during the process of reading texts of English for science and technology on a web-based cumulative sentence analysis system. For the analysis, the association-rule, data mining technique…

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. Fabrication of Nanohydroxyapatite/Poly(caprolactone Composite Microfibers Using Electrospinning Technique for Tissue Engineering Applications

    Directory of Open Access Journals (Sweden)

    Mohd Izzat Hassan

    2014-01-01

    Full Text Available Tissue engineering fibrous scaffolds serve as three-dimensional (3D environmental framework by mimicking the extracellular matrix (ECM for cells to grow. Biodegradable polycaprolactone (PCL microfibers were fabricated to mimic the ECM as a scaffold with 7.5% (w/v and 12.5% (w/v concentrations. Lower PCL concentration of 7.5% (w/v resulted in microfibers with bead defects. The average diameter of fibers increased at higher voltage and the distance of tip to collector. Further investigation was performed by the incorporation of nanosized hydroxyapatite (nHA into microfibers. The incorporation of 10% (w/w nHA with 7.5% (w/v PCL solution produced submicron sized beadless fibers. The microfibrous scaffolds were evaluated using various techniques. Biodegradable PCL and nHA/PCL could be promising for tissue engineering scaffold application.

  1. A systematic review of applying modern software engineering techniques to developing robotic systems

    Directory of Open Access Journals (Sweden)

    Claudia Pons

    2012-01-01

    Full Text Available Robots have become collaborators in our daily life. While robotic systems become more and more complex, the need to engineer their software development grows as well. The traditional approaches used in developing these software systems are reaching their limits; currently used methodologies and tools fall short of addressing the needs of such complex software development. Separating robotics’ knowledge from short-cycled implementation technologies is essential to foster reuse and maintenance. This paper presents a systematic review (SLR of the current use of modern software engineering techniques for developing robotic software systems and their actual automation level. The survey was aimed at summarizing existing evidence concerning applying such technologies to the field of robotic systems to identify any gaps in current research to suggest areas for further investigation and provide a background for positioning new research activities.

  2. Impedance-based monitoring for tissue engineering applications

    DEFF Research Database (Denmark)

    Canali, Chiara; Heiskanen, Arto; Martinsen, Ø.G.

    2015-01-01

    Impedance is a promising technique for sensing the overall process of tissue engineering. Different electrode configurations can be used to characterize the scaffold that supports cell organization in terms of hydrogel polymerization and degree of porosity, monitoring cell loading, cell prolifera...

  3. 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

  4. 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

  5. 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...

  6. Optimal Tuner Selection for Kalman-Filter-Based Aircraft Engine Performance Estimation

    Science.gov (United States)

    Simon, Donald L.; Garg, Sanjay

    2011-01-01

    An emerging approach in the field of aircraft engine controls and system health management is the inclusion of real-time, onboard models for the inflight estimation of engine performance variations. This technology, typically based on Kalman-filter concepts, enables the estimation of unmeasured engine performance parameters that can be directly utilized by controls, prognostics, and health-management applications. A challenge that complicates this practice is the fact that an aircraft engine s performance is affected by its level of degradation, generally described in terms of unmeasurable health parameters such as efficiencies and flow capacities related to each major engine module. Through Kalman-filter-based estimation techniques, the level of engine performance degradation can be estimated, given that there are at least as many sensors as health parameters to be estimated. However, in an aircraft engine, the number of sensors available is typically less than the number of health parameters, presenting an under-determined estimation problem. A common approach to address this shortcoming is to estimate a subset of the health parameters, referred to as model tuning parameters. The problem/objective is to optimally select the model tuning parameters to minimize Kalman-filterbased estimation error. A tuner selection technique has been developed that specifically addresses the under-determined estimation problem, where there are more unknown parameters than available sensor measurements. A systematic approach is applied to produce a model tuning parameter vector of appropriate dimension to enable estimation by a Kalman filter, while minimizing the estimation error in the parameters of interest. Tuning parameter selection is performed using a multi-variable iterative search routine that seeks to minimize the theoretical mean-squared estimation error of the Kalman filter. This approach can significantly reduce the error in onboard aircraft engine parameter estimation

  7. Applications of nuclear techniques in agronomy as a contribution to the integral formation of agronomical engineers

    International Nuclear Information System (INIS)

    Núñez Meireles, Mónica; Hernández Martínez, Asiel; Charbonet Martell, Miguel Enrique

    2016-01-01

    Nowadays, nuclear research applied to agriculture and food is a reality, and is being supported by institutions like the International Atomic Energy Agency and the United Nations Food and Agriculture Organization. Stable and radioactive isotopes are used in different ways in agricultural research mainly in the determination of required conditions to optimize efficiency in the use of fertilizers and water, the development of high yield agricultural and horticultural varieties, reduction of diseases due to contaminated food, and soil erosion studies among others. Accordingly to the study carried out, there is not much knowledge about nuclear phenomena applied to agronomy. Nevertheless there is a positive criterion about the introduction of these topics in Agronomical Engineers education, by mean of implementing an optional subject, aimed at explaining different spheres of action of nuclear techniques in Agriculture. Consequently, it would be possible achieving the linkage of agronomical engineers with the nuclear techniques, though respecting at the same time the professional model of this career. Moreover, it is also proposed to include laboratory practices in the curriculum of this career, using nuclear techniques and showing their proper linkage with Agronomy. (author)

  8. 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.

  9. 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.

  10. 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....

  11. 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...

  12. A review of optimization techniques used in the design of fibre composite structures for civil engineering applications

    International Nuclear Information System (INIS)

    Awad, Ziad K.; Aravinthan, Thiru; Zhuge, Yan; Gonzalez, Felipe

    2012-01-01

    Highlights: → We reviewed existing optimization techniques of fibre composite structures. → Proposed an improved methodology for design optimization. → Comparison showed the MRDO is most suitable. -- Abstract: Fibre composite structures have become the most attractive candidate for civil engineering applications. Fibre reinforced plastic polymer (FRP) composite materials have been used in the rehabilitation and replacement of the old degrading traditional structures or build new structures. However, the lack of design standards for civil infrastructure limits their structural applications. The majority of the existing applications have been designed based on the research and guidelines provided by the fibre composite manufacturers or based on the designer's experience. It has been a tendency that the final structure is generally over-designed. This paper provides a review on the available studies related to the design optimization of fibre composite structures used in civil engineering such as; plate, beam, box beam, sandwich panel, bridge girder, and bridge deck. Various optimization methods are presented and compared. In addition, the importance of using the appropriate optimization technique is discussed. An improved methodology, which considering experimental testing, numerical modelling, and design constrains, is proposed in the paper for design optimization of composite structures.

  13. 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

  14. Liquid Tunable Microlenses based on MEMS techniques

    Science.gov (United States)

    Zeng, Xuefeng; Jiang, Hongrui

    2013-01-01

    The recent rapid development in microlens technology has provided many opportunities for miniaturized optical systems, and has found a wide range of applications. Of these microlenses, tunable-focus microlenses are of special interest as their focal lengths can be tuned using micro-scale actuators integrated with the lens structure. Realization of such tunable microlens generally relies on the microelectromechanical system (MEMS) technologies. Here, we review the recent progress in tunable liquid microlenses. The underlying physics relevant to these microlenses are first discussed, followed by description of three main categories of tunable microlenses involving MEMS techniques, mechanically driven, electrically driven, and those integrated within microfluidic systems. PMID:24163480

  15. Model-driven engineering of information systems principles, techniques, and practice

    CERN Document Server

    Cretu, Liviu Gabriel

    2015-01-01

    Model-driven engineering (MDE) is the automatic production of software from simplified models of structure and functionality. It mainly involves the automation of the routine and technologically complex programming tasks, thus allowing developers to focus on the true value-adding functionality that the system needs to deliver. This book serves an overview of some of the core topics in MDE. The volume is broken into two sections offering a selection of papers that helps the reader not only understand the MDE principles and techniques, but also learn from practical examples. Also covered are the

  16. The Application of Biomedical Engineering Techniques to the Diagnosis and Management of Tropical Diseases: A Review

    Directory of Open Access Journals (Sweden)

    Fatimah Ibrahim

    2015-03-01

    Full Text Available This paper reviews a number of biomedical engineering approaches to help aid in the detection and treatment of tropical diseases such as dengue, malaria, cholera, schistosomiasis, lymphatic filariasis, ebola, leprosy, leishmaniasis, and American trypanosomiasis (Chagas. Many different forms of non-invasive approaches such as ultrasound, echocardiography and electrocardiography, bioelectrical impedance, optical detection, simplified and rapid serological tests such as lab-on-chip and micro-/nano-fluidic platforms and medical support systems such as artificial intelligence clinical support systems are discussed. The paper also reviewed the novel clinical diagnosis and management systems using artificial intelligence and bioelectrical impedance techniques for dengue clinical applications.

  17. The application of biomedical engineering techniques to the diagnosis and management of tropical diseases: a review.

    Science.gov (United States)

    Ibrahim, Fatimah; Thio, Tzer Hwai Gilbert; Faisal, Tarig; Neuman, Michael

    2015-03-23

    This paper reviews a number of biomedical engineering approaches to help aid in the detection and treatment of tropical diseases such as dengue, malaria, cholera, schistosomiasis, lymphatic filariasis, ebola, leprosy, leishmaniasis, and American trypanosomiasis (Chagas). Many different forms of non-invasive approaches such as ultrasound, echocardiography and electrocardiography, bioelectrical impedance, optical detection, simplified and rapid serological tests such as lab-on-chip and micro-/nano-fluidic platforms and medical support systems such as artificial intelligence clinical support systems are discussed. The paper also reviewed the novel clinical diagnosis and management systems using artificial intelligence and bioelectrical impedance techniques for dengue clinical applications.

  18. Java Based Symbolic Circuit Solver For Electrical Engineering Curriculum

    Directory of Open Access Journals (Sweden)

    Ruba Akram Amarin

    2012-11-01

    Full Text Available The interactive technical electronic book, TechEBook, currently under development at the University of Central Florida (UCF, introduces a paradigm shift by replacing the traditional electrical engineering course with topic-driven modules that provide a useful tool for engineers and scientists. The TechEBook comprises the two worlds of classical circuit books and interactive operating platforms such as iPads, laptops and desktops. The TechEBook provides an interactive applets screen that holds many modules, each of which has a specific application in the self learning process. This paper describes one of the interactive techniques in the TechEBook known as Symbolic Circuit Solver (SymCirc. The SymCirc develops a versatile symbolic based linear circuit with a switches solver. The solver works by accepting a Netlist and the element that the user wants to find the voltage across or current on, as input parameters. Then it either produces the plot or the time domain expression of the output. Frequency domain plots or Symbolic Transfer Functions are also produced. The solver gets its input from a Web-based GUI circuit drawer developed at UCF. Typical simulation tools that electrical engineers encounter are numerical in nature, that is, when presented with an input circuit they iteratively solve the circuit across a set of small time steps. The result is represented as a data set of output versus time, which can be plotted for further inspection. Such results do not help users understand the ultimate nature of circuits as Linear Time Invariant systems with a finite dimensional basis in the solution space. SymCirc provides all simulation results as time domain expressions composed of the basic functions that exclusively include exponentials, sines, cosines and/or t raised to any power. This paper explains the motivation behind SymCirc, the Graphical User Interface front end and how the solver actually works. The paper also presents some examples and

  19. Ant colony optimization-based firewall anomaly mitigation engine.

    Science.gov (United States)

    Penmatsa, Ravi Kiran Varma; Vatsavayi, Valli Kumari; Samayamantula, Srinivas Kumar

    2016-01-01

    A firewall is the most essential component of network perimeter security. Due to human error and the involvement of multiple administrators in configuring firewall rules, there exist common anomalies in firewall rulesets such as Shadowing, Generalization, Correlation, and Redundancy. There is a need for research on efficient ways of resolving such anomalies. The challenge is also to see that the reordered or resolved ruleset conforms to the organization's framed security policy. This study proposes an ant colony optimization (ACO)-based anomaly resolution and reordering of firewall rules called ACO-based firewall anomaly mitigation engine. Modified strategies are also introduced to automatically detect these anomalies and to minimize manual intervention of the administrator. Furthermore, an adaptive reordering strategy is proposed to aid faster reordering when a new rule is appended. The proposed approach was tested with different firewall policy sets. The results were found to be promising in terms of the number of conflicts resolved, with minimal availability loss and marginal security risk. This work demonstrated the application of a metaheuristic search technique, ACO, in improving the performance of a packet-filter firewall with respect to mitigating anomalies in the rules, and at the same time demonstrated conformance to the security policy.

  20. Knowledge based engineering techniques to support aircraft design and optimization

    NARCIS (Netherlands)

    La Rocca, G.

    2011-01-01

    Since the 1960s, the demand for air transportation has doubled every 15 years, resilient to every oil crises and international events. However, the current capability of the air transport management system, the demand of increasingly growing levels of quality, comfort, safety and security, and,

  1. 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

  2. Using Web 2.0 Techniques in NASA's Ares Engineering Operations Network (AEON) Environment - First Impressions

    Science.gov (United States)

    Scott, David W.

    2010-01-01

    The Mission Operations Laboratory (MOL) at Marshall Space Flight Center (MSFC) is responsible for Engineering Support capability for NASA s Ares rocket development and operations. In pursuit of this, MOL is building the Ares Engineering and Operations Network (AEON), a web-based portal to support and simplify two critical activities: Access and analyze Ares manufacturing, test, and flight performance data, with access to Shuttle data for comparison Establish and maintain collaborative communities within the Ares teams/subteams and with other projects, e.g., Space Shuttle, International Space Station (ISS). AEON seeks to provide a seamless interface to a) locally developed engineering applications and b) a Commercial-Off-The-Shelf (COTS) collaborative environment that includes Web 2.0 capabilities, e.g., blogging, wikis, and social networking. This paper discusses how Web 2.0 might be applied to the typically conservative engineering support arena, based on feedback from Integration, Verification, and Validation (IV&V) testing and on searching for their use in similar environments.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Structural reliability analysis based on the cokriging technique

    International Nuclear Information System (INIS)

    Zhao Wei; Wang Wei; Dai Hongzhe; Xue Guofeng

    2010-01-01

    Approximation methods are widely used in structural reliability analysis because they are simple to create and provide explicit functional relationships between the responses and variables in stead of the implicit limit state function. Recently, the kriging method which is a semi-parameter interpolation technique that can be used for deterministic optimization and structural reliability has gained popularity. However, to fully exploit the kriging method, especially in high-dimensional problems, a large number of sample points should be generated to fill the design space and this can be very expensive and even impractical in practical engineering analysis. Therefore, in this paper, a new method-the cokriging method, which is an extension of kriging, is proposed to calculate the structural reliability. cokriging approximation incorporates secondary information such as the values of the gradients of the function being approximated. This paper explores the use of the cokriging method for structural reliability problems by comparing it with the Kriging method based on some numerical examples. The results indicate that the cokriging procedure described in this work can generate approximation models to improve on the accuracy and efficiency for structural reliability problems and is a viable alternative to the kriging.

  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. Flow and Mixture Optimization for a Fuel Stratification Engine Using PIV and PLIF Techniques

    Science.gov (United States)

    Li, Y.; Zhao, H.; Ma, T.

    2006-07-01

    This paper describes an application of PIV (particle image velocimetry) and two-tracer PLIF (planar laser-induced florescence) techniques to optimize the in-cylinder flow and to visualize two fuels distribution simultaneously for developing a fuel stratification engine. This research was carried out on a twin-spark four-valve SI engine. The PIV measurement results shows that a strong tumbling flow was produced in the cylinder as the intake valves were shrouded. The flow exhibited a symmetrical distribution in the plane perpendicular to the cylinder axis from the early stage of intake until the late stage of compression. This flow pattern helps to stratify the two fuels introduced from separate ports into two regions laterally. The stratification of fuels was observed visually by the two-tracer PLIF technique. During the PLIF measurement, two tracers, 3- pentanone and N, N-dimethylaniline (DMA), were doped into two fuels, hexane and iso-octane, respectively. Their fluorescence emissions were separated by two optical band-pass filters and recorded by a single ICCD camera simultaneously via an image doubling system. The PLIF measurement result shows that two fuels were well stratified.

  10. Accelerator based techniques for contraband detection

    Science.gov (United States)

    Vourvopoulos, George

    1994-05-01

    It has been shown that narcotics, explosives, and other contraband materials, contain various chemical elements such as H, C, N, O, P, S, and Cl in quantities and ratios that differentiate them from each other and from other innocuous substances. Neutrons and γ-rays have the ability to penetrate through various materials at large depths. They are thus able, in a non-intrusive way, to interrogate volumes ranging from suitcases to Sea-Land containers, and have the ability to image the object with an appreciable degree of reliability. Neutron induced reactions such as (n, γ), (n, n') (n, p) or proton induced γ-resonance absorption are some of the reactions currently investigated for the identification of the chemical elements mentioned above. Various DC and pulsed techniques are discussed and their advantages, characteristics, and current progress are shown. Areas where use of these methods is currently under evaluation are detection of hidden explosives, illicit drug interdiction, chemical war agents identification, nuclear waste assay, nuclear weapons destruction and others.

  11. 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.

  12. 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.

  13. 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...

  14. 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.

  15. Fabrication and Characterization of three dimensional Scaffolds for tissue engineering application via microstereolithography technique

    International Nuclear Information System (INIS)

    Marina Talib; Covington, J.A.; Dove, A.; Bolarinwa, A.; Grover, L.

    2012-01-01

    Microstereolithography is a method used for rapid proto typing of polymeric and ceramic components. This technique converts a computer-aided design (CAD) to a three dimensional (3D) model, and enables layer-per-layer fabrication curing a liquid resin with UV-light or laser source. However, the use of stereo lithography in tissue engineering has not been significantly explored possibly due to the lack of commercially available implantable or biocompatible materials from the SL industry. This study seeks to develop a range of new bio-compatible/degradable materials that are compatible with a commercial 3D direct manufacture system (envisionTEC Desktop). Firstly, a selection of multifunctional polymer and calcium phosphate were studied in order to formulate biodegradable photo polymer resin for specific tissue engineering applications. A 3D structure was successfully fabricated from the formulated photo curable resins. The photo polymer of ceramic suspension was prepared with the addition of 50-70 wt % of calcium pyrophosphate (CPP) and hydroxyapatite (HA). They were then sintered at high temperature for polymer removal, to obtain a ceramic of the desired porosity. Mechanical properties, morphology and calcium phosphate content of the sintered polymers were characterised and investigated with SEM and XRD, respectively. The addition of calcium phosphate coupled with high temperature sintering, had a significant effect on the mechanical properties exhibited by the bio ceramic. The successful fabrication of novel bio ceramic polymer composite with MSL technique offers the possibility of designing complex tissue scaffolds with optimum mechanical properties for specific tissue engineering applications. (author)

  16. Engineering aperiodic nanostructured surfaces for scattering-based optical devices

    Science.gov (United States)

    Lee, Yuk Kwan Sylvanus

    Novel optical devices such as biosensors, color displays and authentication devices can be obtained from the distinctive light scattering properties of resonant nanoparticles and nanostructured arrays. These arrays can be optimized through the choice of material, particle morphology and array geometry. In this thesis, by engineering the multi-frequency colorimetric responses of deterministic aperiodic nanostructured surfaces (DANS) with various spectral Fourier properties, I designed, fabricated and characterized scattering-based devices for optical biosensing and structural coloration applications. In particular, using analytical and numerical optimization, colorimetric biosensors are designed and fabricated with conventional electron beam lithography, and characterized using dark-field scattering imaging as well as image autocorrelation analysis of scattered intensity in the visible spectral range. These sensors, which consist of aperiodic surfaces ranging from quasi-periodic to pseudo-random structures with flat Fourier spectra, sustain highly complex structural resonances that enable a novel optical sensing approach beyond the traditional Bragg scattering. To this end, I have experimentally demonstrated that DANS with engineered structural colors are capable of detecting nanoscale protein monolayers with significantly enhanced sensitivity over periodic structures. In addition, different aperiodic arrays of gold (Au) nanoparticles are integrated with polydimethylsiloxane (PDMS) microfluidic structures by soft-lithographic micro-imprint techniques. Distinctive scattering spectral shifts and spatial modifications of structural color patterns in response to refractive index variations were simultaneously measured. The successful integration of DANS with microfluidics technology has introduced a novel opto-fluidic sensing platform for label-free and multiplexed lab-on-a-chip applications. Moreover, by studying the isotropic scattering properties of homogenized

  17. Wavelet-based de-noising techniques in MRI

    Czech Academy of Sciences Publication Activity Database

    Bartušek, Karel; Přinosil, J.; Smékal, Z.

    2011-01-01

    Roč. 104, č. 3 (2011), s. 480-488 ISSN 0169-2607 R&D Projects: GA MŠk ED0017/01/01; GA ČR GAP102/11/0318 Institutional research plan: CEZ:AV0Z20650511 Keywords : wavelet transformation * filtering technique * magnetic resonance imaging Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.516, year: 2011

  18. CT-based Techniques for Brain Perfusion.

    Science.gov (United States)

    Krishnan, Pradeep; Murphy, Amanda; Aviv, Richard I

    2017-06-01

    Recent rapid advances in endovascular treatment for acute ischemic stroke highlight the crucial role of neuroimaging especially multimodal computed tomography (CT) including CT perfusion in stroke triage and management decisions. With an increasing focus on changes in cerebral physiology along with time-based matrices in clinical decisions for acute ischemic stroke, CT perfusion provides a rapid and practical modality for assessment and identification of salvageable tissue at risk and infarct core and provides a better understanding of the changes in cerebral physiology. Although there are challenges with the lack of standardization and accuracy of quantitative assessment, CT perfusion is evolving as a cornerstone for imaging-based strategies in the rapid management of acute ischemic stroke.

  19. Applications of Chondrocyte-Based Cartilage Engineering: An Overview

    Directory of Open Access Journals (Sweden)

    Abdul-Rehman Phull

    2016-01-01

    Full Text Available Chondrocytes are the exclusive cells residing in cartilage and maintain the functionality of cartilage tissue. Series of biocomponents such as different growth factors, cytokines, and transcriptional factors regulate the mesenchymal stem cells (MSCs differentiation to chondrocytes. The number of chondrocytes and dedifferentiation are the key limitations in subsequent clinical application of the chondrocytes. Different culture methods are being developed to overcome such issues. Using tissue engineering and cell based approaches, chondrocytes offer prominent therapeutic option specifically in orthopedics for cartilage repair and to treat ailments such as tracheal defects, facial reconstruction, and urinary incontinence. Matrix-assisted autologous chondrocyte transplantation/implantation is an improved version of traditional autologous chondrocyte transplantation (ACT method. An increasing number of studies show the clinical significance of this technique for the chondral lesions treatment. Literature survey was carried out to address clinical and functional findings by using various ACT procedures. The current study was conducted to study the pharmacological significance and biomedical application of chondrocytes. Furthermore, it is inferred from the present study that long term follow-up studies are required to evaluate the potential of these methods and specific positive outcomes.

  20. Engineered pigments based on iridescent cellulose nanocrystal films.

    Science.gov (United States)

    Bardet, Raphael; Roussel, Francine; Coindeau, Stéphane; Belgacem, Naceur; Bras, Julien

    2015-05-20

    A simple method to produce biobased iridescent pigments from cellulose nanocrystal (CNC) films is reported. The process consists of forming nanostructured films from a CNC liquid-crystalline suspension and an appropriate dry grinding. The features of the iridescent pigments are described; they have a flake-like morphology with a thickness of 25 μm. However, because of the presence of sulfate groups, thermal degradation and high redispersion in water occur, which affect the iridescent property of these biobased pigments. To overcome such limitations, two post-treatments are proposed. The sulfate ester groups are removed from the iridescent pigments with vacuum overdrying. The mass loss of iridescent pigment in water is reduced with an increase of the ionic strength in the aqueous medium by NaCl addition. These post-treatments have proven to be efficient and engineered pigments based on CNC films can be used to add anticounterfeiting features to packaging manufactured by classical paper techniques or extrusion. Copyright © 2015 Elsevier Ltd. All rights reserved.

  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. 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...

  3. 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...

  4. FDI and Accommodation Using NN Based Techniques

    Science.gov (United States)

    Garcia, Ramon Ferreiro; de Miguel Catoira, Alberto; Sanz, Beatriz Ferreiro

    Massive application of dynamic backpropagation neural networks is used on closed loop control FDI (fault detection and isolation) tasks. The process dynamics is mapped by means of a trained backpropagation NN to be applied on residual generation. Process supervision is then applied to discriminate faults on process sensors, and process plant parameters. A rule based expert system is used to implement the decision making task and the corresponding solution in terms of faults accommodation and/or reconfiguration. Results show an efficient and robust FDI system which could be used as the core of an SCADA or alternatively as a complement supervision tool operating in parallel with the SCADA when applied on a heat exchanger.

  5. Huffman-based code compression techniques for embedded processors

    KAUST Repository

    Bonny, Mohamed Talal

    2010-09-01

    The size of embedded software is increasing at a rapid pace. It is often challenging and time consuming to fit an amount of required software functionality within a given hardware resource budget. Code compression is a means to alleviate the problem by providing substantial savings in terms of code size. In this article we introduce a novel and efficient hardware-supported compression technique that is based on Huffman Coding. Our technique reduces the size of the generated decoding table, which takes a large portion of the memory. It combines our previous techniques, Instruction Splitting Technique and Instruction Re-encoding Technique into new one called Combined Compression Technique to improve the final compression ratio by taking advantage of both previous techniques. The instruction Splitting Technique is instruction set architecture (ISA)-independent. It splits the instructions into portions of varying size (called patterns) before Huffman coding is applied. This technique improves the final compression ratio by more than 20% compared to other known schemes based on Huffman Coding. The average compression ratios achieved using this technique are 48% and 50% for ARM and MIPS, respectively. The Instruction Re-encoding Technique is ISA-dependent. It investigates the benefits of reencoding unused bits (we call them reencodable bits) in the instruction format for a specific application to improve the compression ratio. Reencoding those bits can reduce the size of decoding tables by up to 40%. Using this technique, we improve the final compression ratios in comparison to the first technique to 46% and 45% for ARM and MIPS, respectively (including all overhead that incurs). The Combined Compression Technique improves the compression ratio to 45% and 42% for ARM and MIPS, respectively. In our compression technique, we have conducted evaluations using a representative set of applications and we have applied each technique to two major embedded processor architectures

  6. 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…

  7. 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

  8. 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…

  9. 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

  10. Alginate based scaffolds for bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Valente, J.F.A.; Valente, T.A.M. [CICS-UBI - Centro de Investigacao em Ciencias da Saude, Faculdade de Ciencias da Saude, Universidade da Beira Interior, Covilha (Portugal); Alves, P.; Ferreira, P. [CIEPQPF, Departamento de Engenharia Quimica, Universidade de Coimbra, Polo II, Pinhal de Marrocos, 3030-290 Coimbra (Portugal); Silva, A. [Centro de Ciencia e Tecnologia Aeroespaciais, Universidade da Beira Interior, Covilha (Portugal); Correia, I.J., E-mail: icorreia@ubi.pt [CICS-UBI - Centro de Investigacao em Ciencias da Saude, Faculdade de Ciencias da Saude, Universidade da Beira Interior, Covilha (Portugal)

    2012-12-01

    The design and production of scaffolds for bone tissue regeneration is yet unable to completely reproduce the native bone properties. In the present study new alginate microparticle and microfiber aggregated scaffolds were produced to be applied in this area of regenerative medicine. The scaffolds' mechanical properties were characterized by thermo mechanical assays. Their morphological characteristics were evaluated by isothermal nitrogen adsorption and scanning electron microscopy. The density of both types of scaffolds was determined by helium pycnometry and mercury intrusion porosimetry. Furthermore, scaffolds' cytotoxic profiles were evaluated in vitro by seeding human osteoblast cells in their presence. The results obtained showed that scaffolds have good mechanical and morphological properties compatible with their application as bone substitutes. Moreover, scaffold's biocompatibility was confirmed by the observation of cell adhesion and proliferation after 5 days of being seeded in their presence and by non-radioactive assays. - Highlights: Black-Right-Pointing-Pointer Design and production of scaffolds for bone tissue regeneration. Black-Right-Pointing-Pointer Microparticle and microfiber alginate scaffolds were produced through a particle aggregation technique; Black-Right-Pointing-Pointer Scaffolds' mechanically and biologically properties were characterized through in vitro studies;.

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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

  16. Finger Based Techniques for Nonvisual Touchscreen Text Entry

    OpenAIRE

    Fakrudeen, Mohammed; Yousef, Sufian; Miraz, Mahdi H.; Hussein, AbdelRahman Hamza

    2017-01-01

    This research proposes Finger Based Technique (FBT) for non-visual touch screen device interaction designed for blind users. Based on the proposed technique, the blind user can access virtual keys based on finger holding positions. Three different models have been proposed. They are Single Digit Finger-Digit Input (FDI), Double Digit FDI for digital text entry, and Finger-Text Input (FTI) for normal text entry. All the proposed models were implemented with voice feedback while enabling touch ...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-08-15

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

  18. Data base systems in electronic design engineering

    Science.gov (United States)

    Williams, D.

    1980-01-01

    The concepts of an integrated design data base system (DBMS) as it might apply to an electronic design company are discussed. Data elements of documentation, project specifications, project tracking, firmware, software, electronic and mechanical design can be integrated and managed through a single DBMS. Combining the attributes of a DBMS data handler with specialized systems and functional data can provide users with maximum flexibility, reduced redundancy, and increased overall systems performance. Although some system overhead is lost due to redundancy in transitory data, it is believed the combination of the two data types is advisable rather than trying to do all data handling through a single DBMS.

  19. 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.

  20. Tissue-engineering-based Strategies for Regenerative Endodontics

    Science.gov (United States)

    Albuquerque, M.T.P.; Valera, M.C.; Nakashima, M.; Nör, J.E.; Bottino, M.C.

    2014-01-01

    Stemming from in vitro and in vivo pre-clinical and human models, tissue-engineering-based strategies continue to demonstrate great potential for the regeneration of the pulp-dentin complex, particularly in necrotic, immature permanent teeth. Nanofibrous scaffolds, which closely resemble the native extracellular matrix, have been successfully synthesized by various techniques, including but not limited to electrospinning. A common goal in scaffold synthesis has been the notion of promoting cell guidance through the careful design and use of a collection of biochemical and physical cues capable of governing and stimulating specific events at the cellular and tissue levels. The latest advances in processing technologies allow for the fabrication of scaffolds where selected bioactive molecules can be delivered locally, thus increasing the possibilities for clinical success. Though electrospun scaffolds have not yet been tested in vivo in either human or animal pulpless models in immature permanent teeth, recent studies have highlighted their regenerative potential both from an in vitro and in vivo (i.e., subcutaneous model) standpoint. Possible applications for these bioactive scaffolds continue to evolve, with significant prospects related to the regeneration of both dentin and pulp tissue and, more recently, to root canal disinfection. Nonetheless, no single implantable scaffold can consistently guide the coordinated growth and development of the multiple tissue types involved in the functional regeneration of the pulp-dentin complex. The purpose of this review is to provide a comprehensive perspective on the latest discoveries related to the use of scaffolds and/or stem cells in regenerative endodontics. The authors focused this review on bioactive nanofibrous scaffolds, injectable scaffolds and stem cells, and pre-clinical findings using stem-cell-based strategies. These topics are discussed in detail in an attempt to provide future direction and to shed light on

  1. Techniques based on genetic algorithms for large deflection ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    with 'exact' solutions, if available, are provided. Keywords. Genetic algorithms; large deflection analysis; analysis of beams. 1. Introduction. The beam is one of the most common structural elements used in a variety of aerospace, civil and mechanical engineering structures. Linear beam theories based on a linear moment-.

  2. Inverter-based circuit design techniques for low supply voltages

    CERN Document Server

    Palani, Rakesh Kumar

    2017-01-01

    This book describes intuitive analog design approaches using digital inverters, providing filter architectures and circuit techniques enabling high performance analog circuit design. The authors provide process, supply voltage and temperature (PVT) variation-tolerant design techniques for inverter based circuits. They also discuss various analog design techniques for lower technology nodes and lower power supply, which can be used for designing high performance systems-on-chip.    .

  3. Array-based techniques for fingerprinting medicinal herbs

    Directory of Open Access Journals (Sweden)

    Xue Charlie

    2011-05-01

    Full Text Available Abstract Poor quality control of medicinal herbs has led to instances of toxicity, poisoning and even deaths. The fundamental step in quality control of herbal medicine is accurate identification of herbs. Array-based techniques have recently been adapted to authenticate or identify herbal plants. This article reviews the current array-based techniques, eg oligonucleotides microarrays, gene-based probe microarrays, Suppression Subtractive Hybridization (SSH-based arrays, Diversity Array Technology (DArT and Subtracted Diversity Array (SDA. We further compare these techniques according to important parameters such as markers, polymorphism rates, restriction enzymes and sample type. The applicability of the array-based methods for fingerprinting depends on the availability of genomics and genetics of the species to be fingerprinted. For the species with few genome sequence information but high polymorphism rates, SDA techniques are particularly recommended because they require less labour and lower material cost.

  4. Cost Engineering Techniques and Their Applicability for Cost Estimation of Organic Rankine Cycle Systems

    Directory of Open Access Journals (Sweden)

    Sanne Lemmens

    2016-06-01

    Full Text Available The potential of organic Rankine cycle (ORC systems is acknowledged by both considerable research and development efforts and an increasing number of applications. Most research aims at improving ORC systems through technical performance optimization of various cycle architectures and working fluids. The assessment and optimization of technical feasibility is at the core of ORC development. Nonetheless, economic feasibility is often decisive when it comes down to considering practical instalments, and therefore an increasing number of publications include an estimate of the costs of the designed ORC system. Various methods are used to estimate ORC costs but the resulting values are rarely discussed with respect to accuracy and validity. The aim of this paper is to provide insight into the methods used to estimate these costs and open the discussion about the interpretation of these results. A review of cost engineering practices shows there has been a long tradition of industrial cost estimation. Several techniques have been developed, but the expected accuracy range of the best techniques used in research varies between 10% and 30%. The quality of the estimates could be improved by establishing up-to-date correlations for the ORC industry in particular. Secondly, the rapidly growing ORC cost literature is briefly reviewed. A graph summarizing the estimated ORC investment costs displays a pattern of decreasing costs for increasing power output. Knowledge on the actual costs of real ORC modules and projects remains scarce. Finally, the investment costs of a known heat recovery ORC system are discussed and the methodologies and accuracies of several approaches are demonstrated using this case as benchmark. The best results are obtained with factorial estimation techniques such as the module costing technique, but the accuracies may diverge by up to +30%. Development of correlations and multiplication factors for ORC technology in particular is

  5. Peptide based hydrogels for bone tissue engineering

    International Nuclear Information System (INIS)

    Ranny, H.R.; Schneider, J.P.

    2007-01-01

    Peptide hydrogels are potentially ideal scaffolds for tissue repair and regeneration due to their ability to mimic natural extra cellular matrix. The 20 amino acid peptide HPL8 (H2N- VKVKVKVKVDPP TKVKVKVKV-CONH2), has been shown to fold and self-assemble into a rigid hydrogel based on Environmental cues such as pH, salt, and temperature. Due to its environmental responsiveness, hydrogel assembly can be induced by cell culture media, allowing for 3D encapsulation of osteogenic cells. Initially, 20 cultures of MC3T3 cells proved that the hydrogel is nontoxic and sustains cellular attachment in the absence of serum proteins without altering the physical properties of the hydrogel. The cell-material structure relationship in normal and pathological conditions was further investigated by 3D encapsulation. Cell were viable for 3 weeks and grew in clonogenic spheroids. Characterization of the proliferation, differentiation and constitutive expression of various osteoblastic markers was performed using spectrophotometric methods. The well-defined, fibrillar nanostructure of the hydrogel directs the attachment and attachment and growth of osteoblast cells and dictates the mineralization of hydroxyapatite in a manner similar to bone. This study will enable control over the interaction of cellular systems with the peptide hydrogel with designs for biomedical applications of bone repair. (author)

  6. Fuel saver based on electromagnetic induction for automotive engine

    Science.gov (United States)

    Siregar, Houtman P.; Sibarani, Maradu

    2007-12-01

    In the considered research is designed and analyzed the performance of the fuel saver which is based on electromagnetic induction for automotive diesel engine. The fuel saver which is based on permanent magnet has sold in market and its performance has tested. In comparison to the former fuel saver, in the proposed work is produced fuel saver which is based on electromagnetic induction. The considered research is the continuation of my former work. Performance of the produced fuel saver which is installed in the fuel line of internal combustion engine rig is compared to the performance of the standard internal combustion engine rig Speed of the engine, wire diameter of coil, and number of coil which is coiled in the winding of the the fuel saver are chosen as the testing variables. The considered research has succeeded to design the fuel saver which is based on electromagnetic induction for saving the automotive fuel consumption. Results of the research show that the addition of the fuel saver which is based on electromagnetic induction to the flow of the diesel fuel can significantly save the automative fuel consumption. In addition the designed fuel saver can reduce the opacity of the emission gas.

  7. Stem cell homing-based tissue engineering using bioactive materials

    Science.gov (United States)

    Yu, Yinxian; Sun, Binbin; Yi, Chengqing; Mo, Xiumei

    2017-06-01

    Tissue engineering focuses on repairing tissue and restoring tissue functions by employing three elements: scaffolds, cells and biochemical signals. In tissue engineering, bioactive material scaffolds have been used to cure tissue and organ defects with stem cell-based therapies being one of the best documented approaches. In the review, different biomaterials which are used in several methods to fabricate tissue engineering scaffolds were explained and show good properties (biocompatibility, biodegradability, and mechanical properties etc.) for cell migration and infiltration. Stem cell homing is a recruitment process for inducing the migration of the systemically transplanted cells, or host cells, to defect sites. The mechanisms and modes of stem cell homing-based tissue engineering can be divided into two types depending on the source of the stem cells: endogenous and exogenous. Exogenous stem cell-based bioactive scaffolds have the challenge of long-term culturing in vitro and for endogenous stem cells the biochemical signal homing recruitment mechanism is not clear yet. Although the stem cell homing-based bioactive scaffolds are attractive candidates for tissue defect therapies, based on in vitro studies and animal tests, there is still a long way before clinical application.

  8. Validation of a satellite-based cyclogenesis technique over the ...

    Indian Academy of Sciences (India)

    2013), it is called a depression over the NIO. It becomes a cyclonic storm if the MSW is 34 knots or more. The intensity of the low pressure sys- tem is also defined based on Dvorak's technique. (Dvorak 1984) using satellite imageries. In this technique, the intensity is defined with an assigned number in a scale of 1–8 in an ...

  9. Estimate-Merge-Technique-based algorithms to track an underwater ...

    Indian Academy of Sciences (India)

    In this paper, two novel methods based on the Estimate Merge Technique are proposed. The Estimate Merge Technique involves a process of getting a final estimate by the fusion of a posteriori estimates given by different nonlinear estimates, which are in turn driven by the towed array bearing-only measurements.

  10. 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.

  11. Experience with performance based training of nuclear criticality safety engineers

    International Nuclear Information System (INIS)

    Taylor, R.G.

    1993-01-01

    Historically, new entrants to the practice of nuclear criticality safety have learned their job primarily by on-the-job training (OJT) often by association with an experienced nuclear criticality safety engineer who probably also learned their job by OJT. Typically, the new entrant learned what he/she needed to know to solve a particular problem and accumulated experience as more problems were solved. It is likely that more formalism will be required in the future. Current US Department of Energy requirements for those positions which have to demonstrate qualification indicate that it 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 i's incompletely developed in some areas. Details of this analysis are provided in this report

  12. Introduction to Problem Based Learning for Engineering Education

    DEFF Research Database (Denmark)

    Moesby, Egon; Rosenørn, Torben

    2003-01-01

    Documentation material and working papers for the workshop "Introduction to Problem Based Learning for Engineering Education" held at Chiang Mai University, Chiang Mai, Thailand, 6 - 10 October 2003. The material support the workshop where the participants go through a complete pre-planning cycle...

  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. Engineering Student Self-Assessment through Confidence-Based Scoring

    Science.gov (United States)

    Yuen-Reed, Gigi; Reed, Kyle B.

    2015-01-01

    A vital aspect of an answer is the confidence that goes along with it. Misstating the level of confidence one has in the answer can have devastating outcomes. However, confidence assessment is rarely emphasized during typical engineering education. The confidence-based scoring method described in this study encourages students to both think about…

  15. Implementation of a Project-Based Telecommunications Engineering Design Course

    Science.gov (United States)

    Aliakbarian, Hadi; Soh, Ping Jack; Farsi, Saeed; Xu, Hantao; Van Lil, Emmanuel H. E. M. J. C.; Nauwelaers, Bart K. J. C.; Vandenbosch, Guy A. E.; Schreurs, Dominique M. M.-P.

    2014-01-01

    This paper describes and discusses the implementation of a project-based graduate design course in telecommunications engineering. This course, which requires a combination of technical and soft skills for its completion, enables guided independent learning (GIL) and application of technical knowledge acquired from classroom learning. Its main…

  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. Scenario Based E-Learning in Electrical Engineering Education

    Science.gov (United States)

    Tambunan, Hamonangan; Dalimunte, Amirhud; Silitonga, Marsangkap

    2017-01-01

    The scenario based e-learning in Electrical Engineering Education Learning (EEEL) was developed by covering the scope and characteristics of all subjects and the competence unit of graduates in the field of pedagogy, professional, social and personality, with url addresed http://jpte-ft-unimed.edu20.org. The scenario incorporates the concept of…

  18. Computer-based Reverse Engineering of a Manual Weighting ...

    African Journals Online (AJOL)

    Computer based reverse engineering of the weighing spring balance is a systematic reconstruction of a manual spring weighting balance to include a digital hardware circuit that can interfaces the spring balance to the computer. This research work shows the benefits of interfacing a weighting balance to a digital computer.

  19. 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.

  20. Techniques to assess acoustic-structure interaction in liquid rocket engines

    Science.gov (United States)

    Davis, R. Benjamin

    Acoustoelasticity is the study of the dynamic interaction between elastic structures and acoustic enclosures. In this dissertation, acoustoelasticity is considered in the context of liquid rocket engine design. The techniques presented here can be used to determine which forcing frequencies are important in acoustoelastic systems. With a knowledge of these frequencies, an analyst can either find ways to attenuate the excitation at these frequencies or alter the system in such a way that the prescribed excitations do result in a resonant condition. The end result is a structural component that is less susceptible to failure. The research scope is divided into three parts. In the first part, the dynamics of cylindrical shells submerged in liquid hydrogen (LH2) and liquid oxygen (LOX) are considered. The shells are bounded by rigid outer cylinders. This configuration gives rise to two fluid-filled cavities---an inner cylindrical cavity and an outer annular cavity. Such geometries are common in rocket engine design. The natural frequencies and modes of the fluid-structure system are computed by combining the rigid wall acoustic cavity modes and the in vacuo structural modes into a system of coupled ordinary differential equations. Eigenvalue veering is observed near the intersections of the curves representing natural frequencies of the rigid wall acoustic and the in vacuo structural modes. In the case of a shell submerged in LH2, system frequencies near these intersections are as much as 30% lower than the corresponding in vacuo structural frequencies. Due to its high density, the frequency reductions in the presence of LOX are even more dramatic. The forced responses of a shell submerged in LH2 and LOX while subject to a harmonic point excitation are also presented. The responses in the presence of fluid are found to be quite distinct from those of the structure in vacuo. In the second part, coupled mode theory is used to explore the fundamental features of

  1. Component-Based Engineering of Knowledge-Enabled Systems: Research Vision and Strategy

    National Research Council Canada - National Science Library

    Goodburn, D

    2001-01-01

    ...'. The Software Systems Engineering (SSE) group of ITD is currently conducting research into new software engineering principles and practices, collectively referred to as component-based software...

  2. improvement of digital image watermarking techniques based on FPGA implementation

    International Nuclear Information System (INIS)

    EL-Hadedy, M.E

    2006-01-01

    digital watermarking provides the ownership of a piece of digital data by marking the considered data invisibly or visibly. this can be used to protect several types of multimedia objects such as audio, text, image and video. this thesis demonstrates the different types of watermarking techniques such as (discrete cosine transform (DCT) and discrete wavelet transform (DWT) and their characteristics. then, it classifies these techniques declaring their advantages and disadvantages. an improved technique with distinguished features, such as peak signal to noise ratio ( PSNR) and similarity ratio (SR) has been introduced. the modified technique has been compared with the other techniques by measuring heir robustness against differ attacks. finally, field programmable gate arrays (FPGA) based implementation and comparison, for the proposed watermarking technique have been presented and discussed

  3. The detection of bulk explosives using nuclear-based techniques

    Energy Technology Data Exchange (ETDEWEB)

    Morgado, R.E.; Gozani, T.; Seher, C.C.

    1988-01-01

    In 1986 we presented a rationale for the detection of bulk explosives based on nuclear techniques that addressed the requirements of civil aviation security in the airport environment. Since then, efforts have intensified to implement a system based on thermal neutron activation (TNA), with new work developing in fast neutron and energetic photon reactions. In this paper we will describe these techniques and present new results from laboratory and airport testing. Based on preliminary results, we contended in our earlier paper that nuclear-based techniques did provide sufficiently penetrating probes and distinguishable detectable reaction products to achieve the FAA operational goals; new data have supported this contention. The status of nuclear-based techniques for the detection of bulk explosives presently under investigation by the US Federal Aviation Administration (FAA) is reviewed. These include thermal neutron activation (TNA), fast neutron activation (FNA), the associated particle technique, nuclear resonance absorption, and photoneutron activation. The results of comprehensive airport testing of the TNA system performed during 1987-88 are summarized. From a technical point of view, nuclear-based techniques now represent the most comprehensive and feasible approach for meeting the operational criteria of detection, false alarms, and throughput. 9 refs., 5 figs., 2 tabs.

  4. Mechatronic Control Engineering: A Problem Oriented And Project Based Learning Curriculum In Mechatronic

    DEFF Research Database (Denmark)

    Pedersen, Henrik Clemmensen; Andersen, Torben Ole; Hansen, Michael Rygaard

    2008-01-01

    Mechatronics is a field of multidisciplinary engineering that not only requires knowledge about different technical areas, but also insight into how to combine technologies optimally, to design efficient products and systems.This paper addresses the group project based and problem-oriented learning...... the well established methods from control engineering form very powerful techniques in both analysis and synthesis of mechatronic systems. The necessary skills for mechatronic engineers are outlined followed up by a discussion on how problem oriented project based learning is implemented. A complete...

  5. Conceptual Comparison of Population Based Metaheuristics for Engineering Problems

    Directory of Open Access Journals (Sweden)

    Oluwole Adekanmbi

    2015-01-01

    Full Text Available Metaheuristic algorithms are well-known optimization tools which have been employed for solving a wide range of optimization problems. Several extensions of differential evolution have been adopted in solving constrained and nonconstrained multiobjective optimization problems, but in this study, the third version of generalized differential evolution (GDE is used for solving practical engineering problems. GDE3 metaheuristic modifies the selection process of the basic differential evolution and extends DE/rand/1/bin strategy in solving practical applications. The performance of the metaheuristic is investigated through engineering design optimization problems and the results are reported. The comparison of the numerical results with those of other metaheuristic techniques demonstrates the promising performance of the algorithm as a robust optimization tool for practical purposes.

  6. Conceptual comparison of population based metaheuristics for engineering problems.

    Science.gov (United States)

    Adekanmbi, Oluwole; Green, Paul

    2015-01-01

    Metaheuristic algorithms are well-known optimization tools which have been employed for solving a wide range of optimization problems. Several extensions of differential evolution have been adopted in solving constrained and nonconstrained multiobjective optimization problems, but in this study, the third version of generalized differential evolution (GDE) is used for solving practical engineering problems. GDE3 metaheuristic modifies the selection process of the basic differential evolution and extends DE/rand/1/bin strategy in solving practical applications. The performance of the metaheuristic is investigated through engineering design optimization problems and the results are reported. The comparison of the numerical results with those of other metaheuristic techniques demonstrates the promising performance of the algorithm as a robust optimization tool for practical purposes.

  7. The Effectiveness Of Physics Based Research In Learning Engineering Physics

    OpenAIRE

    -, Usmeldi

    2015-01-01

    This research aims to know the effect of implementation the research based learning to master properly physics concepts and students' generic ability. This research used experiment method with pretest-posttest group control design. The results of this research were the research based learning was effective to improving students' mastery of physics concepts and it was also developing the students' generic ability. The recommendation suggested to lecturer of engineering physics is implementing ...

  8. IBRI-CASONTO: Ontology-based semantic search engine

    Directory of Open Access Journals (Sweden)

    Awny Sayed

    2017-11-01

    Full Text Available The vast availability of information, that added in a very fast pace, in the data repositories creates a challenge in extracting correct and accurate information. Which has increased the competition among developers in order to gain access to technology that seeks to understand the intent researcher and contextual meaning of terms. While the competition for developing an Arabic Semantic Search systems are still in their infancy, and the reason could be traced back to the complexity of Arabic Language. It has a complex morphological, grammatical and semantic aspects, as it is a highly inflectional and derivational language. In this paper, we try to highlight and present an Ontological Search Engine called IBRI-CASONTO for Colleges of Applied Sciences, Oman. Our proposed engine supports both Arabic and English language. It is also employed two types of search which are a keyword-based search and a semantics-based search. IBRI-CASONTO is based on different technologies such as Resource Description Framework (RDF data and Ontological graph. The experiments represent in two sections, first it shows a comparison among Entity-Search and the Classical-Search inside the IBRI-CASONTO itself, second it compares the Entity-Search of IBRI-CASONTO with currently used search engines, such as Kngine, Wolfram Alpha and the most popular engine nowadays Google, in order to measure their performance and efficiency.

  9. 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....

  10. 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.

  11. 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. This paper describes the working group's success in identifying V&V tasks that could be performed in the domain engineering and transition levels of reuse-based software engineering. The primary motivation for V&V at the domain level is to provide assurance that the domain requirements are correct and that the domain artifacts correctly implement the domain requirements. A secondary motivation is the possible elimination of redundant V&V activities at the application level. The group also considered the criteria and motivation for performing V&V in domain engineering.

  12. Probability based high temperature engineering creep and structural fire resistance

    CERN Document Server

    Razdolsky, Leo

    2017-01-01

    This volume on structural fire resistance is for aerospace, structural, and fire prevention engineers; architects, and educators. It bridges the gap between prescriptive- and performance-based methods and simplifies very complex and comprehensive computer analyses to the point that the structural fire resistance and high temperature creep deformations will have a simple, approximate analytical expression that can be used in structural analysis and design. The book emphasizes methods of the theory of engineering creep (stress-strain diagrams) and mathematical operations quite distinct from those of solid mechanics absent high-temperature creep deformations, in particular the classical theory of elasticity and structural engineering. Dr. Razdolsky’s previous books focused on methods of computing the ultimate structural design load to the different fire scenarios. The current work is devoted to the computing of the estimated ultimate resistance of the structure taking into account the effect of high temperatur...

  13. 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.

  14. Quantum engineering of transistors based on 2D materials heterostructures

    Science.gov (United States)

    Iannaccone, Giuseppe; Bonaccorso, Francesco; Colombo, Luigi; Fiori, Gianluca

    2018-03-01

    Quantum engineering entails atom-by-atom design and fabrication of electronic devices. This innovative technology that unifies materials science and device engineering has been fostered by the recent progress in the fabrication of vertical and lateral heterostructures of two-dimensional materials and by the assessment of the technology potential via computational nanotechnology. But how close are we to the possibility of the practical realization of next-generation atomically thin transistors? In this Perspective, we analyse the outlook and the challenges of quantum-engineered transistors using heterostructures of two-dimensional materials against the benchmark of silicon technology and its foreseeable evolution in terms of potential performance and manufacturability. Transistors based on lateral heterostructures emerge as the most promising option from a performance point of view, even if heterostructure formation and control are in the initial technology development stage.

  15. A new construction technique for tissue-engineered heart valves using the self-assembly method.

    Science.gov (United States)

    Tremblay, Catherine; Ruel, Jean; Bourget, Jean-Michel; Laterreur, Véronique; Vallières, Karine; Tondreau, Maxime Y; Lacroix, Dan; Germain, Lucie; Auger, François A

    2014-11-01

    Tissue engineering appears as a promising option to create new heart valve substitutes able to overcome the serious drawbacks encountered with mechanical substitutes or tissue valves. The objective of this article is to present the construction method of a new entirely biological stentless aortic valve using the self-assembly method and also a first assessment of its behavior in a bioreactor when exposed to a pulsatile flow. A thick tissue was created by stacking several fibroblast sheets produced with the self-assembly technique. Different sets of custom-made templates were designed to confer to the thick tissue a three-dimensional (3D) shape similar to that of a native aortic valve. The construction of the valve was divided in two sequential steps. The first step was the installation of the thick tissue in a flat preshaping template followed by a 4-week maturation period. The second step was the actual cylindrical 3D forming of the valve. The microscopic tissue structure was assessed using histological cross sections stained with Masson's Trichrome and Picrosirius Red. The thick tissue remained uniformly populated with cells throughout the construction steps and the dense extracellular matrix presented corrugated fibers of collagen. This first prototype of tissue-engineered heart valve was installed in a bioreactor to assess its capacity to sustain a light pulsatile flow at a frequency of 0.5 Hz. Under the light pulsed flow, it was observed that the leaflets opened and closed according to the flow variations. This study demonstrates that the self-assembly method is a viable option for the construction of complex 3D shapes, such as heart valves, with an entirely biological material.

  16. Engineering satellite-based navigation and timing global navigation satellite systems, signals, and receivers

    CERN Document Server

    Betz, J

    2016-01-01

    This book describes the design and performance analysis of satnav systems, signals, and receivers. It also provides succinct descriptions and comparisons of all the world’s satnav systems. Its comprehensive and logical structure addresses all satnav signals and systems in operation and being developed. Engineering Satellite-Based Navigation and Timing: Global Navigation Satellite Systems, Signals, and Receivers provides the technical foundation for designing and analyzing satnav signals, systems, and receivers. Its contents and structure address all satnav systems and signals: legacy, modernized, and new. It combines qualitative information with detailed techniques and analyses, providing a comprehensive set of insights and engineering tools for this complex multidisciplinary field. Part I describes system and signal engineering including orbital mechanics and constellation design, signal design principles and underlying considerations, link budgets, qua tifying receiver performance in interference, and e...

  17. Research of Data Acquisition and Analysis System for Internal Combustion Engine Based on DSP

    International Nuclear Information System (INIS)

    Gao, Y H; Tian, X L; Cheng, P; Chang, X; Dou, W J

    2006-01-01

    In the paper, the structure, working principle, functions and characteristics of an data acquisition and analysis system for internal combustion engines (I.C. engine) based on DSP is introduced. The DSP can not only acquire and analyze the data alone, also can work with the PC together to form data acquisition and analysis system with high speed and large memory. The system takes advantages of TMS320F2812's plenty of peripherals on chip, becomes small and easy for installation. USB technique is used to translate data between DSP and PC in high speed, so the system's real time processing is proved very much. It is proved that the designed system can acquire and analyze the steady and transient parameters of the I.C. engine very well

  18. Tissue-engineered trachea regeneration using decellularized trachea matrix treated with laser micropore technique.

    Science.gov (United States)

    Xu, Yong; Li, Dan; Yin, Zongqi; He, Aijuan; Lin, Miaomiao; Jiang, Gening; Song, Xiao; Hu, Xuefei; Liu, Yi; Wang, Jinpeng; Wang, Xiaoyun; Duan, Liang; Zhou, Guangdong

    2017-08-01

    Tissue-engineered trachea provides a promising approach for reconstruction of long segmental tracheal defects. However, a lack of ideal biodegradable scaffolds greatly restricts its clinical translation. Decellularized trachea matrix (DTM) is considered a proper scaffold for trachea cartilage regeneration owing to natural tubular structure, cartilage matrix components, and biodegradability. However, cell residual and low porosity of DTM easily result in immunogenicity and incomplete cartilage regeneration. To address these problems, a laser micropore technique (LMT) was applied in the current study to modify trachea sample porosity to facilitate decellular treatment and cell ingrowth. Decellularization processing demonstrated that cells in LMT treated samples were more easily removed compared with untreated native trachea. Furthermore, after optimizing the protocols of LMT and decellular treatments, the LMT-treated DTM (LDTM) could retain their original tubular shape with only mild extracellular matrix damage. After seeding with chondrocytes and culture in vitro for 8 weeks, the cell-LDTM constructs formed tubular cartilage with relatively homogenous cell distribution in both micropores and bilateral surfaces. In vivo results further confirmed that the constructs could form mature tubular cartilage with increased DNA and cartilage matrix contents, as well as enhanced mechanical strength, compared with native trachea. Collectively, these results indicate that LDTM is an ideal scaffold for tubular cartilage regeneration and, thus, provides a promising strategy for functional reconstruction of trachea cartilage. Lacking ideal biodegradable scaffolds greatly restricts development of tissue-engineered trachea. Decellularized trachea matrix (DTM) is considered a proper scaffold for trachea cartilage regeneration. However, cell residual and low porosity of DTM easily result in immunogenicity and incomplete cartilage regeneration. By laser micropore technique (LMT), the

  19. Metabolic engineering for isoprenoid-based biofuel production.

    Science.gov (United States)

    Gupta, P; Phulara, S C

    2015-09-01

    Sustainable economic and industrial growth is the need of the hour and it requires renewable energy resources having better performance and compatibility with existing fuel infrastructure from biological routes. Isoprenoids (C ≥ 5) can be a potential alternative due to their diverse nature and physiochemical properties similar to that of petroleum based fuels. In the past decade, extensive research has been done to utilize metabolic engineering strategies in micro-organisms primarily, (i) to overcome the limitations associated with their natural and non-natural production and (ii) to develop commercially competent microbial strain for isoprenoid-based biofuel production. This review briefly describes the engineered isoprenoid biosynthetic pathways in well-characterized microbial systems for the production of several isoprenoid-based biofuels and fuel precursors. © 2015 The Society for Applied Microbiology.

  20. In-Service Aircraft Engine System Life Monitor Using Advanced Life-Estimating Technique, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — It is proposed to develop an accurate in-service aircraft engine life monitor system for the prediction of remaining component and system life for aircraft engines....

  1. 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

  2. Power system stabilizers based on modern control techniques

    Energy Technology Data Exchange (ETDEWEB)

    Malik, O.P.; Chen, G.P.; Zhang, Y.; El-Metwally, K. [Calgary Univ., AB (Canada). Dept. of Electrical and Computer Engineering

    1994-12-31

    Developments in digital technology have made it feasible to develop and implement improved controllers based on sophisticated control techniques. Power system stabilizers based on adaptive control, fuzzy logic and artificial networks are being developed. Each of these control techniques possesses unique features and strengths. In this paper, the relative performance of power systems stabilizers based on adaptive control, fuzzy logic and neural network, both in simulation studies and real time tests on a physical model of a power system, is presented and compared to that of a fixed parameter conventional power system stabilizer. (author) 16 refs., 45 figs., 3 tabs.

  3. An introduction to laser-based tissue microdissection techniques.

    Science.gov (United States)

    Curran, Stephanie; Murray, Graeme I

    2005-01-01

    The development and application of laser-based tissue microdissection techniques has provided a major impetus to the sensitive and specific molecular analysis of solid tissues and tumors. This chapter provides an overview of the different laser-based microdissection systems and an introduction to the principles involved in the function and applications of these individual systems.

  4. Simulation-based optimization parametric optimization techniques and reinforcement learning

    CERN Document Server

    Gosavi, Abhijit

    2003-01-01

    Simulation-Based Optimization: Parametric Optimization Techniques and Reinforcement Learning introduces the evolving area of simulation-based optimization. The book's objective is two-fold: (1) It examines the mathematical governing principles of simulation-based optimization, thereby providing the reader with the ability to model relevant real-life problems using these techniques. (2) It outlines the computational technology underlying these methods. Taken together these two aspects demonstrate that the mathematical and computational methods discussed in this book do work. Broadly speaking, the book has two parts: (1) parametric (static) optimization and (2) control (dynamic) optimization. Some of the book's special features are: *An accessible introduction to reinforcement learning and parametric-optimization techniques. *A step-by-step description of several algorithms of simulation-based optimization. *A clear and simple introduction to the methodology of neural networks. *A gentle introduction to converg...

  5. Mechatronic Control Engineering: A Problem Oriented And Project Based Learning Curriculum In Mechatronic

    DEFF Research Database (Denmark)

    Pedersen, Henrik Clemmensen; Andersen, Torben Ole; Hansen, Michael Rygaard

    2008-01-01

    Mechatronics is a field of multidisciplinary engineering that not only requires knowledge about different technical areas, but also insight into how to combine technologies optimally, to design efficient products and systems.This paper addresses the group project based and problem-oriented learning...... approach in relation to a mechatronic education, which makes it possible for the student to get in-depth skills in the area of mechatronics very fast. The trends and applications of mechatronic engineering and research are illustrated. Control engineering plays a central role in this context, where...... the well established methods from control engineering form very powerful techniques in both analysis and synthesis of mechatronic systems. The necessary skills for mechatronic engineers are outlined followed up by a discussion on how problem oriented project based learning is implemented. A complete...

  6. Effects of Engineering Design-Based Science on Elementary School Science Students' Engineering Identity Development across Gender and Grade

    Science.gov (United States)

    Capobianco, Brenda M.; Yu, Ji H.; French, Brian F.

    2015-04-01

    The integration of engineering concepts and practices into elementary science education has become an emerging concern for science educators and practitioners, alike. Moreover, how children, specifically preadolescents (grades 1-5), engage in engineering design-based learning activities may help science educators and researchers learn more about children's earliest identification with engineering. The purpose of this study was to examine the extent to which engineering identity differed among preadolescents across gender and grade, when exposing students to engineering design-based science learning activities. Five hundred fifty preadolescent participants completed the Engineering Identity Development Scale (EIDS), a recently developed measure with validity evidence that characterizes children's conceptions of engineering and potential career aspirations. Data analyses of variance among four factors (i.e., gender, grade, and group) indicated that elementary school students who engaged in the engineering design-based science learning activities demonstrated greater improvements on the EIDS subscales compared to those in the comparison group. Specifically, students in the lower grade levels showed substantial increases, while students in the higher grade levels showed decreases. Girls, regardless of grade level and participation in the engineering learning activities, showed higher scores in the academic subscale compared to boys. These findings suggest that the integration of engineering practices in the science classroom as early as grade one shows potential in fostering and sustaining student interest, participation, and self-concept in engineering and science.

  7. 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)

  8. 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)

  9. Beam modulation: A novel ToF-technique for high resolution diffraction at the Beamline for European Materials Engineering Research (BEER)

    Science.gov (United States)

    Rouijaa, M.; Kampmann, R.; Šaroun, J.; Fenske, J.; Beran, P.; Müller, M.; Lukáš, P.; Schreyer, A.

    2018-05-01

    The Beamline for European Materials Engineering Research (BEER) is under construction at the European Spallation Source (ESS) in Lund, Sweden. A basic requirement on BEER is to make best use of the long ESS pulse (2.86 ms) for engineering investigations. High-resolution diffraction, however, demands timing resolution up to 0.1% corresponding to a pulse length down to about 70 μs for the case of thermal neutrons (λ ∼ 1.8 Å). Such timing resolution can be achieved by pulse shaping techniques cutting a short section out of the long pulse, and thus paying for resolution by strong loss of intensity. In contrast to this, BEER proposes a novel operation mode called pulse modulation technique based on a new chopper design, which extracts several short pulses out of the long ESS pulse, and hence leads to a remarkable gain of intensity compared to nowadays existing conventional pulse shaping techniques. The potential of the new technique can be used with full advantage for investigating strains and textures of highly symmetric materials. Due to its instrument design and the high brilliance of the ESS pulse, BEER is expected to become the European flagship for engineering research for strain mapping and texture analysis.

  10. The Research of Histogram Enhancement Technique Based on Matlab Software

    Directory of Open Access Journals (Sweden)

    Li Kai

    2014-08-01

    Full Text Available Histogram enhancement technique has been widely applied as a typical pattern in digital image processing. The paper is based on Matlab software, through the two ways of histogram equalization and histogram specification technologies to deal with the darker images, using two methods of partial equilibrium and mapping histogram to transform the original histograms, thereby enhanced the image information. The results show that these two kinds of techniques both can significantly improve the image quality and enhance the image feature.

  11. An Image Registration Based Technique for Noninvasive Vascular Elastography

    OpenAIRE

    Valizadeh, Sina; Makkiabadi, Bahador; Mirbagheri, Alireza; Soozande, Mehdi; Manwar, Rayyan; Mozaffarzadeh, Moein; Nasiriavanaki, Mohammadreza

    2018-01-01

    Non-invasive vascular elastography is an emerging technique in vascular tissue imaging. During the past decades, several techniques have been suggested to estimate the tissue elasticity by measuring the displacement of the Carotid vessel wall. Cross correlation-based methods are the most prevalent approaches to measure the strain exerted in the wall vessel by the blood pressure. In the case of a low pressure, the displacement is too small to be apparent in ultrasound imaging, especially in th...

  12. MPPT Technique Based on Current and Temperature Measurements

    Directory of Open Access Journals (Sweden)

    Eduardo Moreira Vicente

    2015-01-01

    Full Text Available This paper presents a new maximum power point tracking (MPPT method based on the measurement of temperature and short-circuit current, in a simple and efficient approach. These measurements, which can precisely define the maximum power point (MPP, have not been used together in other existing techniques. The temperature is measured with a low cost sensor and the solar irradiance is estimated through the relationship of the measured short-circuit current and its reference. Fast tracking speed and stable steady-state operation are advantages of this technique, which presents higher performance when compared to other well-known techniques.

  13. Recent progress in genome engineering techniques in the silkworm, Bombyx mori.

    Science.gov (United States)

    Daimon, Takaaki; Kiuchi, Takashi; Takasu, Yoko

    2014-01-01

    Rapid advances in genome engineering tools, such as zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and the clustered regularly interspaced palindromic repeats/CRISPR-associated (CRISPR/Cas) system, have enabled efficient gene knockout experiments in a wide variety of organisms. Here, we review the recent progress in targeted gene disruption techniques in the silkworm, Bombyx mori. Although efficiency of targeted mutagenesis was very low in an early experiment using ZFNs, recent studies have shown that TALENs can induce highly efficient mutagenesis of desired target genes in Bombyx. Notably, mutation frequencies induced by TALENs can reach more than 50% of G0 gametes. Thus, TALENs can now be used as a standard tool for gene targeting studies, even when mutant phenotypes are unknown. We also propose guidelines for experimental design and strategy for knockout experiments in Bombyx. Genome editing technologies will greatly increase the usefulness of Bombyx as a model for lepidopteran insects, the major agricultural pests, and lead to sophisticated breeding of Bombyx for use in sericulture and biotechnology. © 2013 The Authors Development, Growth & Differentiation © 2013 Japanese Society of Developmental Biologists.

  14. Camera-based calibration techniques for seamless multiprojector displays.

    Science.gov (United States)

    Brown, Michael; Majumder, Aditi; Yang, Ruigang

    2005-01-01

    Multiprojector, large-scale displays are used in scientific visualization, virtual reality, and other visually intensive applications. In recent years, a number of camera-based computer vision techniques have been proposed to register the geometry and color of tiled projection-based display. These automated techniques use cameras to "calibrate" display geometry and photometry, computing per-projector corrective warps and intensity corrections that are necessary to produce seamless imagery across projector mosaics. These techniques replace the traditional labor-intensive manual alignment and maintenance steps, making such displays cost-effective, flexible, and accessible. In this paper, we present a survey of different camera-based geometric and photometric registration techniques reported in the literature to date. We discuss several techniques that have been proposed and demonstrated, each addressing particular display configurations and modes of operation. We overview each of these approaches and discuss their advantages and disadvantages. We examine techniques that address registration on both planar (video walls) and arbitrary display surfaces and photometric correction for different kinds of display surfaces. We conclude with a discussion of the remaining challenges and research opportunities for multiprojector displays.

  15. Adapting planning and scheduling concepts to an engineering perspective: Key issues and successful techniques

    International Nuclear Information System (INIS)

    Finnegan, J.M.

    1986-01-01

    Traditional approaches to engineering planning are slanted toward the formats and interests of downstream implementation, and do not always consider the form and criticality of the front-end engineering development process. These processes and scopes are less defined and more subjective than most construction and operations tasks, and require flexible scheduling methods. This paper discusses the characteristics and requirement of engineering schedules, presents concepts for approaching planning in this field, and illustrates simple methods for developing and analyzing engineering plans, and evaluating schedule performance. Engineering plans are structured into a schedule hierarchy which delineates appropriate control and responsibilities, and is governed by key evaluation and decision milestones. Schedule risk analysis considers the uncertainty of engineering tasks, and critical resource constraints. Methods to evaluate schedule performance recognize that engineers and managers are responsible for adequate planning and forecasting, and quality decisions, even if they cannot control all factors influencing schedule results

  16. Efficient Techniques of Sparse Signal Analysis for Enhanced Recovery of Information in Biomedical Engineering and Geosciences

    KAUST Repository

    Sana, Furrukh

    2016-11-01

    Sparse signals are abundant among both natural and man-made signals. Sparsity implies that the signal essentially resides in a small dimensional subspace. The sparsity of the signal can be exploited to improve its recovery from limited and noisy observations. Traditional estimation algorithms generally lack the ability to take advantage of signal sparsity. This dissertation considers several problems in the areas of biomedical engineering and geosciences with the aim of enhancing the recovery of information by exploiting the underlying sparsity in the problem. The objective is to overcome the fundamental bottlenecks, both in terms of estimation accuracies and required computational resources. In the first part of dissertation, we present a high precision technique for the monitoring of human respiratory movements by exploiting the sparsity of wireless ultra-wideband signals. The proposed technique provides a novel methodology of overcoming the Nyquist sampling constraint and enables robust performance in the presence of noise and interferences. We also present a comprehensive framework for the important problem of extracting the fetal electrocardiogram (ECG) signals from abdominal ECG recordings of pregnant women. The multiple measurement vectors approach utilized for this purpose provides an efficient mechanism of exploiting the common structure of ECG signals, when represented in sparse transform domains, and allows leveraging information from multiple ECG electrodes under a joint estimation formulation. In the second part of dissertation, we adopt sparse signal processing principles for improved information recovery in large-scale subsurface reservoir characterization problems. We propose multiple new algorithms for sparse representation of the subsurface geological structures, incorporation of useful prior information in the estimation process, and for reducing computational complexities of the problem. The techniques presented here enable significantly

  17. Toner and paper-based fabrication techniques for microfluidic applications.

    Science.gov (United States)

    Coltro, Wendell Karlos Tomazelli; de Jesus, Dosil Pereira; da Silva, José Alberto Fracassi; do Lago, Claudimir Lucio; Carrilho, Emanuel

    2010-08-01

    The interest in low-cost microfluidic platforms as well as emerging microfabrication techniques has increased considerably over the last years. Toner- and paper-based techniques have appeared as two of the most promising platforms for the production of disposable devices for on-chip applications. This review focuses on recent advances in the fabrication techniques and in the analytical/bioanalytical applications of toner and paper-based devices. The discussion is divided in two parts dealing with (i) toner and (ii) paper devices. Examples of miniaturized devices fabricated by using direct-printing or toner transfer masking in polyester-toner, glass, PDMS as well as conductive platforms as recordable compact disks and printed circuit board are presented. The construction and the use of paper-based devices for off-site diagnosis and bioassays are also described to cover this emerging platform for low-cost diagnostics.

  18. 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

  19. VINE: A Variational Inference -Based Bayesian Neural Network Engine

    Science.gov (United States)

    2018-01-01

    functions and learning rates. The Python implementation that will be turned in is a parameterized implementation of the EASI algorithm in the sense that...Inference (VI) engine to perform inference and learning (statically and on-the-fly) under uncertain or incomplete input and output features. A secondary...realization, and that can not only do inference but also can be retrained on-the-fly based on incoming data. 15. SUBJECT TERMS Machine learning

  20. PC Based Linear Variable Differential Displacement Measurement Uses Optical Technique

    Directory of Open Access Journals (Sweden)

    Tapan Kumar MAITI

    2007-07-01

    Full Text Available PC based linear variable differential displacement (LVDD measurement with optical approach has been presented. The technique is a good blending of both hardware and software and is basically an alternative method of linear variable differential transformer (LVDT. A visual basic (VB programming is used for this PC based measurement. Here the voltage output and the displacement of the reflector can be studied and stored continuously. Theoretical predictions are supported by experimental results. This technique can be used for the measurement of some non-electrical parameters e.g. force, torque and liquid level etc.

  1. Current NMR Techniques for Structure-Based Drug Discovery.

    Science.gov (United States)

    Sugiki, Toshihiko; Furuita, Kyoko; Fujiwara, Toshimichi; Kojima, Chojiro

    2018-01-12

    A variety of nuclear magnetic resonance (NMR) applications have been developed for structure-based drug discovery (SBDD). NMR provides many advantages over other methods, such as the ability to directly observe chemical compounds and target biomolecules, and to be used for ligand-based and protein-based approaches. NMR can also provide important information about the interactions in a protein-ligand complex, such as structure, dynamics, and affinity, even when the interaction is too weak to be detected by ELISA or fluorescence resonance energy transfer (FRET)-based high-throughput screening (HTS) or to be crystalized. In this study, we reviewed current NMR techniques. We focused on recent progress in NMR measurement and sample preparation techniques that have expanded the potential of NMR-based SBDD, such as fluorine NMR ( 19 F-NMR) screening, structure modeling of weak complexes, and site-specific isotope labeling of challenging targets.

  2. Cell sheet-based tissue engineering for fabricating 3-dimensional heart tissues.

    Science.gov (United States)

    Shimizu, Tatsuya

    2014-01-01

    In addition to stem cell biology, tissue engineering is an essential research field for regenerative medicine. In contrast to cell injection, bioengineered tissue transplantation minimizes cell loss and has the potential to repair tissue defects. A popular approach is scaffold-based tissue engineering, which utilizes a biodegradable polymer scaffold for seeding cells; however, new techniques of cell sheet-based tissue engineering have been developed. Cell sheets are harvested from temperature-responsive culture dishes by simply lowering the temperature. Monolayer or stacked cell sheets are transplantable directly onto damaged tissues and cell sheet transplantation has already been clinically applied. Cardiac cell sheet stacking produces pulsatile heart tissue; however, lack of vasculature limits the viable tissue thickness to 3 layers. Multistep transplantation of triple-layer cardiac cell sheets cocultured with endothelial cells has been used to form thick vascularized cardiac tissue in vivo. Furthermore, in vitro functional blood vessel formation within 3-dimensional (3D) tissues has been realized by successfully imitating in vivo conditions. Triple-layer cardiac cell sheets containing endothelial cells were layered on vascular beds and the constructs were media-perfused using novel bioreactor systems. Interestingly, cocultured endothelial cells migrate into the vascular beds and form perfusable blood vessels. An in vitro multistep procedure has also enabled the fabrication of thick, vascularized heart tissues. Cell sheet-based tissue engineering has revealed great potential to fabricate 3D cardiac tissues and should contribute to future treatment of severe heart diseases and human tissue model production.

  3. 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.

  4. Towards effective and robust list-based packet filter for signature-based network intrusion detection: an engineering approach

    DEFF Research Database (Denmark)

    Meng, Weizhi; Li, Wenjuan; Kwok, Lam For

    2017-01-01

    Network intrusion detection systems (NIDSs) which aim to identify various attacks, have become an essential part of current security infrastructure. In particular, signature-based NIDSs are being widely implemented in industry due to their low rate of false alarms. However, the signature matching...... this problem, packet filtration is a promising solution to reduce unwanted traffic. Motivated by this, in this work, a list-based packet filter was designed and an engineering method of combining both blacklist and whitelist techniques was introduced. To further secure such filters against IP spoofing attacks...

  5. A measurement-based technique for incipient anomaly detection

    KAUST Repository

    Harrou, Fouzi

    2016-06-13

    Fault detection is essential for safe operation of various engineering systems. Principal component analysis (PCA) has been widely used in monitoring highly correlated process variables. Conventional PCA-based methods, nevertheless, often fail to detect small or incipient faults. In this paper, we develop new PCA-based monitoring charts, combining PCA with multivariate memory control charts, such as the multivariate cumulative sum (MCUSUM) and multivariate exponentially weighted moving average (MEWMA) monitoring schemes. The multivariate control charts with memory are sensitive to small and moderate faults in the process mean, which significantly improves the performance of PCA methods and widen their applicability in practice. Using simulated data, we demonstrate that the proposed PCA-based MEWMA and MCUSUM control charts are more effective in detecting small shifts in the mean of the multivariate process variables, and outperform the conventional PCA-based monitoring charts. © 2015 IEEE.

  6. Towards a balanced software team formation based on Belbin team role using fuzzy technique

    Science.gov (United States)

    Omar, Mazni; Hasan, Bikhtiyar; Ahmad, Mazida; Yasin, Azman; Baharom, Fauziah; Mohd, Haslina; Darus, Norida Muhd

    2016-08-01

    In software engineering (SE), team roles play significant impact in determining the project success. To ensure the optimal outcome of the project the team is working on, it is essential to ensure that the team members are assigned to the right role with the right characteristics. One of the prevalent team roles is Belbin team role. A successful team must have a balance of team roles. Thus, this study demonstrates steps taken to determine balance of software team formation based on Belbin team role using fuzzy technique. Fuzzy technique was chosen because it allows analyzing of imprecise data and classifying selected criteria. In this study, two roles in Belbin team role, which are Shaper (Sh) and Plant (Pl) were chosen to assign the specific role in software team. Results show that the technique is able to be used for determining the balance of team roles. Future works will focus on the validation of the proposed method by using empirical data in industrial setting.

  7. Engineering the bioelectrochemical interface using functional nanomaterials and microchip technique toward sensitive and portable electrochemical biosensors.

    Science.gov (United States)

    Jia, Xiaofang; Dong, Shaojun; Wang, Erkang

    2016-02-15

    Electrochemical biosensors have played active roles at the forefront of bioanalysis because they have the potential to achieve sensitive, specific and low-cost detection of biomolecules and many others. Engineering the electrochemical sensing interface with functional nanomaterials leads to novel electrochemical biosensors with improved performances in terms of sensitivity, selectivity, stability and simplicity. Functional nanomaterials possess good conductivity, catalytic activity, biocompatibility and high surface area. Coupled with bio-recognition elements, these features can amplify signal transduction and biorecognition events, resulting in highly sensitive biosensing. Additionally, microfluidic electrochemical biosensors have attracted considerable attention on account of their miniature, portable and low-cost systems as well as high fabrication throughput and ease of scaleup. For example, electrochemical enzymetic biosensors and aptamer biosensors (aptasensors) based on the integrated microchip can be used for portable point-of-care diagnostics and environmental monitoring. This review is a summary of our recent progress in the field of electrochemical biosensors, including aptasensors, cytosensors, enzymatic biosensors and self-powered biosensors based on biofuel cells. We presented the advantages that functional nanomaterials and microfluidic chip technology bring to the electrochemical biosensors, together with future prospects and possible challenges. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. 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.

  9. Carbon-based nanomaterials: multifunctional materials for biomedical engineering.

    Science.gov (United States)

    Cha, Chaenyung; Shin, Su Ryon; Annabi, Nasim; Dokmeci, Mehmet R; Khademhosseini, Ali

    2013-04-23

    Functional carbon-based nanomaterials (CBNs) have become important due to their unique combinations of chemical and physical properties (i.e., thermal and electrical conductivity, high mechanical strength, and optical properties), and extensive research efforts are being made to utilize these materials for various industrial applications, such as high-strength materials and electronics. These advantageous properties of CBNs are also actively investigated in several areas of biomedical engineering. This Perspective highlights different types of carbon-based nanomaterials currently used in biomedical applications.

  10. 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.

  11. Advanced alloy design technique: High temperature cobalt base superalloy

    Science.gov (United States)

    Dreshfield, R. L.; Freche, J. C.; Sandrock, G. D.

    1972-01-01

    Advanced alloy design technique was developed for treating alloys that will have extended life in service at high temperature and intermediate temperatures. Process stabilizes microstructure of the alloy by designing it so that compound identified with embrittlement is eliminated or minimized. Design process is being used to develop both nickel and cobalt-base superalloys.

  12. A GIS-Based Optimization Technique for Spatial Location of ...

    African Journals Online (AJOL)

    GIS)-based package; TransCAD v. 5.0 was used to determine the optimal locations of one to ten waste bins. This optimization technique requires less computational time and the output of ten computer runs showed that partial service coverage ...

  13. GIS-based bivariate statistical techniques for groundwater potential ...

    Indian Academy of Sciences (India)

    Groundwater potential analysis prepares better comprehension of hydrological settings of different regions. This study shows the potency of two GIS-based data driven bivariate techniques namely statistical index (SI) and Dempster–Shafer theory (DST) to analyze groundwater potential in Broujerd region of Iran.

  14. Satellite-based technique for nowcasting of thunderstorms over ...

    Indian Academy of Sciences (India)

    Suman Goyal

    2017-08-31

    120 min forecast and longitudinal error varies from 34.1 to 90.2 km for. 30–120 min forecast. Hence there is longitudinal bias in the forecast track of the MCS. 4. Conclusions. The satellite based nowcast technique developed.

  15. Study and analysis of wavelet based image compression techniques ...

    African Journals Online (AJOL)

    This paper presented comprehensive study with performance analysis of very recent Wavelet transform based image compression techniques. Image compression is one of the necessities for such communication. The goals of image compression are to minimize the storage requirement and communication bandwidth.

  16. A novel image inpainting technique based on median diffusion

    Indian Academy of Sciences (India)

    The concept of digital inpainting was introduced by Bertalmio et al. (2000). The proposed algorithm addresses inpainting of images with a homogeneous or heteroge- neous background. The technique is based on diffusing median value of pixels which are exterior to inpainting area into the area to be inpainted. This is a ...

  17. GIS-Based bivariate statistical techniques for groundwater potential ...

    Indian Academy of Sciences (India)

    24

    driven and knowledge-driven models (Corsini ... addition, the usage application of GIS-based SI technique in groundwater potential mapping .... lithology of an given area and affect the drainage density and can be of great big value for to evaluate ...

  18. Novel blood protein based scaffolds for cardiovascular tissue engineering

    Directory of Open Access Journals (Sweden)

    Kuhn Antonia I.

    2016-09-01

    Full Text Available A major challenge in cardiovascular tissue engineering is the fabrication of scaffolds, which provide appropriate morphological and mechanical properties while avoiding undesirable immune reactions. In this study electrospinning was used to fabricate scaffolds out of blood proteins for cardiovascular tissue engineering. Lyophilised porcine plasma was dissolved in deionised water at a final concentration of 7.5% m/v and blended with 3.7% m/v PEO. Electrospinning resulted in homogeneous fibre morphologies with a mean fibre diameter of 151 nm, which could be adapted to create macroscopic shapes (mats, tubes. Cross-linking with glutaraldehyde vapour improved the long-term stability of protein based scaffolds in comparison to untreated scaffolds, resulting in a mass loss of 41% and 96% after 28 days of incubation in aqueous solution, respectively.

  19. Starch based polyhydroxybutyrate production in engineered Escherichia coli.

    Science.gov (United States)

    Bhatia, Shashi Kant; Shim, Young-Ha; Jeon, Jong-Min; Brigham, Christopher J; Kim, Yong-Hyun; Kim, Hyun-Joong; Seo, Hyung-Min; Lee, Ju-Hee; Kim, Jung-Ho; Yi, Da-Hye; Lee, Yoo Kyung; Yang, Yung-Hun

    2015-08-01

    Every year, the amount of chemosynthetic plastic accumulating in the environment is increasing, and significant time is required for decomposition. Bio-based, biodegradable plastic is a promising alternative, but its production is not yet a cost effective process. Decreasing the production cost of polyhydroxyalkanoate by utilizing renewable carbon sources for biosynthesis is an important aspect of commercializing this biodegradable polymer. An Escherichia coli strain that expresses a functional amylase and accumulate polyhydroxybutyrate (PHB), was constructed using different plasmids containing the amylase gene of Panibacillus sp. and PHB synthesis genes from Ralstonia eutropha. This engineered strain can utilize starch as the sole carbon source. The maximum PHB production (1.24 g/L) was obtained with 2% (w/v) starch in M9 media containing 0.15% (w/v) yeast extract and 10 mM glycine betaine. The engineered E. coli SKB99 strain can accumulate intracellular PHB up to 57.4% of cell dry mass.

  20. 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....

  1. Reforming a large lecture modern physics course for engineering majors using a PER-based design

    Science.gov (United States)

    McKagan, S. B.; Perkins, K. K.; Wieman, C. E.

    2007-01-01

    We have reformed a large lecture modern physics course for engineering majors by radically changing both the content and the learning techniques implemented in lecture and homework. Traditionally this course has been taught in a manner similar to the equivalent course for physics majors, focusing on mathematical solutions of abstract problems. Based on interviews with physics and engineering professors, we developed a syllabus and learning goals focused on content that was more useful to our actual student population: engineering majors. The content of this course emphasized reasoning development, model building, and connections to real world applications. In addition we implemented a variety of PER-based learning techniques, including peer instruction, collaborative homework sessions, and interactive simulations. We have assessed the effectiveness of reforms in this course using pre/post surveys on both content and beliefs. We have found significant improvements in both content knowledge and beliefs compared with the same course before implementing these reforms and a corresponding course for physics majors.

  2. Optical supervised filtering technique based on Hopfield neural network

    Science.gov (United States)

    Bal, Abdullah

    2004-11-01

    Hopfield neural network is commonly preferred for optimization problems. In image segmentation, conventional Hopfield neural networks (HNN) are formulated as a cost-function-minimization problem to perform gray level thresholding on the image histogram or the pixels' gray levels arranged in a one-dimensional array [R. Sammouda, N. Niki, H. Nishitani, Pattern Rec. 30 (1997) 921-927; K.S. Cheng, J.S. Lin, C.W. Mao, IEEE Trans. Med. Imag. 15 (1996) 560-567; C. Chang, P. Chung, Image and Vision comp. 19 (2001) 669-678]. In this paper, a new high speed supervised filtering technique is proposed for image feature extraction and enhancement problems by modifying the conventional HNN. The essential improvement in this technique is to use 2D convolution operation instead of weight-matrix multiplication. Thereby, neural network based a new filtering technique has been obtained that is required just 3 × 3 sized filter mask matrix instead of large size weight coefficient matrix. Optical implementation of the proposed filtering technique is executed easily using the joint transform correlator. The requirement of non-negative data for optical implementation is provided by bias technique to convert the bipolar data to non-negative data. Simulation results of the proposed optical supervised filtering technique are reported for various feature extraction problems such as edge detection, corner detection, horizontal and vertical line extraction, and fingerprint enhancement.

  3. Video Multiple Watermarking Technique Based on Image Interlacing Using DWT

    Directory of Open Access Journals (Sweden)

    Mohamed M. Ibrahim

    2014-01-01

    Full Text Available Digital watermarking is one of the important techniques to secure digital media files in the domains of data authentication and copyright protection. In the nonblind watermarking systems, the need of the original host file in the watermark recovery operation makes an overhead over the system resources, doubles memory capacity, and doubles communications bandwidth. In this paper, a robust video multiple watermarking technique is proposed to solve this problem. This technique is based on image interlacing. In this technique, three-level discrete wavelet transform (DWT is used as a watermark embedding/extracting domain, Arnold transform is used as a watermark encryption/decryption method, and different types of media (gray image, color image, and video are used as watermarks. The robustness of this technique is tested by applying different types of attacks such as: geometric, noising, format-compression, and image-processing attacks. The simulation results show the effectiveness and good performance of the proposed technique in saving system resources, memory capacity, and communications bandwidth.

  4. Evaluation of Electrostatic Probe Technique for Detection of Particles Emitted during Turbine Engine Distress

    Science.gov (United States)

    1974-11-01

    out and published by the AFAPL and AFFDL project engineers. The authors would like to thank Mr. David Elkins and Mr. Paul Habil of AFAPL for engine...operation; 2. record baseline probe data (counts and noia levels); 3. introduce distress and verify particle emission (to the extent possible); record

  5. Integrating Creativity Training into Problem and Project-Based Learning (PBL) Curriculum in Engineering Education

    DEFF Research Database (Denmark)

    Zhou, Chunfang

    2012-01-01

    In order to foster creative engineers, a creativity training programme was carried out in medialogy education in a Problem and Project-Based Learning (PBL) environment at Aalborg University, Denmark. This paper focuses on the question of how engineering students perceive the strategy of integrati......, limitations of the programme show that only five days of training did not fit the requirements of learning skills in PBL. So the supervisors are suggested to offer more creativity techniques and process engagement to move projects forward.......In order to foster creative engineers, a creativity training programme was carried out in medialogy education in a Problem and Project-Based Learning (PBL) environment at Aalborg University, Denmark. This paper focuses on the question of how engineering students perceive the strategy of integrating...... creativity training into a PBL curriculum. A total of 20 medialogy students in the training programme were interviewed. The data shows that the training programme was thought useful and students get benefits such as gaining project work skills, creative concepts and confidence of being creative. However...

  6. Cell Sheet-Based Tissue Engineering for Organizing Anisotropic Tissue Constructs Produced Using Microfabricated Thermoresponsive Substrates.

    Science.gov (United States)

    Takahashi, Hironobu; Okano, Teruo

    2015-11-18

    In some native tissues, appropriate microstructures, including orientation of the cell/extracellular matrix, provide specific mechanical and biological functions. For example, skeletal muscle is made of oriented myofibers that is responsible for the mechanical function. Native artery and myocardial tissues are organized three-dimensionally by stacking sheet-like tissues of aligned cells. Therefore, to construct any kind of complex tissue, the microstructures of cells such as myotubes, smooth muscle cells, and cardiomyocytes also need to be organized three-dimensionally just as in the native tissues of the body. Cell sheet-based tissue engineering allows the production of scaffold-free engineered tissues through a layer-by-layer construction technique. Recently, using microfabricated thermoresponsive substrates, aligned cells are being harvested as single continuous cell sheets. The cell sheets act as anisotropic tissue units to build three-dimensional tissue constructs with the appropriate anisotropy. This cell sheet-based technology is straightforward and has the potential to engineer a wide variety of complex tissues. In addition, due to the scaffold-free cell-dense environment, the physical and biological cell-cell interactions of these cell sheet constructs exhibit unique cell behaviors. These advantages will provide important clues to enable the production of well-organized tissues that closely mimic the structure and function of native tissues, required for the future of tissue engineering. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Cogeneration techniques; Les techniques de cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-10-01

    This dossier about cogeneration techniques comprises 12 parts dealing successively with: the advantages of cogeneration (examples of installations, electrical and thermal efficiency); the combustion turbine (principle, performances, types); the alternative internal combustion engines (principle, types, rotation speed, comparative performances); the different configurations of cogeneration installations based on alternative engines and based on steam turbines (coal, heavy fuel and natural gas-fueled turbines); the environmental constraints of combustion turbines (pollutants, techniques of reduction of pollutant emissions); the environmental constraints of alternative internal combustion engines (gas and diesel engines); cogeneration and energy saving; the techniques of reduction of pollutant emissions (pollutants, unburnt hydrocarbons, primary and secondary (catalytic) techniques, post-combustion); the most-advanced configurations of cogeneration installations for enhanced performances (counter-pressure turbines, massive steam injection cycles, turbo-chargers); comparison between the performances of the different cogeneration techniques; the tri-generation technique (compression and absorption cycles). (J.S.)

  8. Integrating knowledge-based techniques into well-test interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, I.W.; Fraser, J.L. [Artificial Intelligence Applications Inst., Edinburgh (United Kingdom)

    1995-04-01

    The goal of the Spirit Project was to develop a prototype of next-generation well-test-interpretation (WTI) software that would include knowledge-based decision support for the WTI model selection task. This paper describes how Spirit makes use of several different types of information (pressure, seismic, petrophysical, geological, and engineering) to support the user in identifying the most appropriate WTI model. Spirit`s knowledge-based approach to type-curve matching is to generate several different feasible interpretations by making assumptions about the possible presence of both wellbore storage and late-time boundary effects. Spirit fuses information from type-curve matching and other data sources by use of a knowledge-based decision model developed in collaboration with a WTI expert. The sponsors of the work have judged the resulting prototype system a success.

  9. Electromagnetism based atmospheric ice sensing technique - A conceptual review

    Directory of Open Access Journals (Sweden)

    U Mughal

    2016-09-01

    Full Text Available Electromagnetic and vibrational properties of ice can be used to measure certain parameters such as ice thickness, type and icing rate. In this paper we present a review of the dielectric based measurement techniques for matter and the dielectric/spectroscopic properties of ice. Atmospheric Ice is a complex material with a variable dielectric constant, but precise calculation of this constant may form the basis for measurement of its other properties such as thickness and strength using some electromagnetic methods. Using time domain or frequency domain spectroscopic techniques, by measuring both the reflection and transmission characteristics of atmospheric ice in a particular frequency range, the desired parameters can be determined.

  10. Preparing systems engineering and computing science students in disciplined methods, quantitative, and advanced statistical techniques to improve process performance

    Science.gov (United States)

    McCray, Wilmon Wil L., Jr.

    The research was prompted by a need to conduct a study that assesses process improvement, quality management and analytical techniques taught to students in U.S. colleges and universities undergraduate and graduate systems engineering and the computing science discipline (e.g., software engineering, computer science, and information technology) degree programs during their academic training that can be applied to quantitatively manage processes for performance. Everyone involved in executing repeatable processes in the software and systems development lifecycle processes needs to become familiar with the concepts of quantitative management, statistical thinking, process improvement methods and how they relate to process-performance. Organizations are starting to embrace the de facto Software Engineering Institute (SEI) Capability Maturity Model Integration (CMMI RTM) Models as process improvement frameworks to improve business processes performance. High maturity process areas in the CMMI model imply the use of analytical, statistical, quantitative management techniques, and process performance modeling to identify and eliminate sources of variation, continually improve process-performance; reduce cost and predict future outcomes. The research study identifies and provides a detail discussion of the gap analysis findings of process improvement and quantitative analysis techniques taught in U.S. universities systems engineering and computing science degree programs, gaps that exist in the literature, and a comparison analysis which identifies the gaps that exist between the SEI's "healthy ingredients " of a process performance model and courses taught in U.S. universities degree program. The research also heightens awareness that academicians have conducted little research on applicable statistics and quantitative techniques that can be used to demonstrate high maturity as implied in the CMMI models. The research also includes a Monte Carlo simulation optimization

  11. An Observed Voting System Based On Biometric Technique

    Directory of Open Access Journals (Sweden)

    B. Devikiruba

    2015-08-01

    Full Text Available ABSTRACT This article describes a computational framework which can run almost on every computer connected to an IP based network to study biometric techniques. This paper discusses with a system protecting confidential information puts strong security demands on the identification. Biometry provides us with a user-friendly method for this identification and is becoming a competitor for current identification mechanisms. The experimentation section focuses on biometric verification specifically based on fingerprints. This article should be read as a warning to those thinking of using methods of identification without first examine the technical opportunities for compromising mechanisms and the associated legal consequences. The development is based on the java language that easily improves software packages that is useful to test new control techniques.

  12. Indirect air cooling techniques for control rod drives in the high temperature engineering test reactor

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Takeshi E-mail: takeda@lstf3.tokai.jaeri.go.jp; Tachibana, Yukio

    2003-07-01

    The high temperature engineering test reactor (HTTR) is the first high-temperature gas-cooled reactor in Japan with reactor outlet gas temperature of 950 deg. C and thermal power of 30 MW. Sixteen pairs of control rods are employed for controlling the reactivity change of the HTTR. Each standpipe for a pair of the control rods, which is placed on the top head dome of the reactor pressure vessel, contains one control rod drive mechanism. The control rod drive mechanism may malfunction because of reduction of the electrical insulation of the electromagnetic clutch when the temperature exceeds 180 deg. C. Because 31 standpipes stand close together in the standpipe room, 16 standpipes for the control rods, which are located at the center, should be cooled effectively. Therefore, the control rod drives are cooled indirectly by forced air circulation through a pair of ring-ducts with proper air outlet nozzles and inlets. Based on analytical results, a pair of the ring-ducts was installed as one of structures in the standpipe room. Evaluation results through the rise-to-power test of the HTTR showed that temperatures of the electromagnetic clutch and the ambient helium gas inside the control rod standpipe should be below the limits of 180 and 75 deg. C, respectively, at full power operation and at the scram from the operation.

  13. Determination Of Horizontal Geodetic Control Networks For Engineering Objects Using Optoelectronic Techniques

    Directory of Open Access Journals (Sweden)

    Ćmielewski Kazimierz

    2015-07-01

    Full Text Available The correctness of the geodetic service of an engineering object not seldom requires designing, alignment or renewing of geodetic situational control points. Building robots often cause that fixed situational control points are partly or completely inaccessible. For setting the position of these control points, there is worked out the methodology using the optoelectronic method. The prepared set of tools realizes the method’s assumptions and enables to determine the sides and control points based on the set of laser planes. In this article there is presented the innovative set of geodetic equipment for fixing horizontal control points. The presented set has been experimentally tested under laboratory conditions taking its functionality, operation range and applied accuracy into account. The measurement accuracy of the set of tools, resulting from identification of the energetic centres of laser planes’ edges, visualizing the sides of geodetic control networks, is within the range of ±0.02mm - ±0.05mm. There were also discussed exemplary versions of shapes and structures of horizontal geodetic control networks (regular and irregular, which are possible to be fixed with the use of the constructed set of tools.

  14. Effects of Engineering Design-Based Science on Elementary School Science Students' Engineering Identity Development across Gender and Grade

    Science.gov (United States)

    Capobianco, Brenda M.; Yu, Ji H.; French, Brian F.

    2015-01-01

    The integration of engineering concepts and practices into elementary science education has become an emerging concern for science educators and practitioners, alike. Moreover, how children, specifically preadolescents (grades 1-5), engage in engineering design-based learning activities may help science educators and researchers learn more about…

  15. Teaching practice and reform of the cultivation of excellent engineer based on the idea of engineering education

    Science.gov (United States)

    Shen, Hanxin; Xiong, Feibing; Huang, Zhangchao; Bai, Zijun

    2017-08-01

    How to realize the joint cultivation of excellent engineer for the school and the enterprise is an important task of the project of excellent engineers. In five years of teaching practice, based on the concept of engineering education certification, through target management of school and enterprise, cultural fusion, stage implementation and feedback, excellent engineer education training plan of opto-electronic specialty is being implemented. It standardizes the specialty construction and practice and explores new teaching management mode, which gets the recognition of graduates and enterprises and achieves a win-win situation for school and enterprise.

  16. 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.

  17. Knowledge Based Engineering for Spatial Database Management and Use

    Science.gov (United States)

    Peuquet, D. (Principal Investigator)

    1984-01-01

    The use of artificial intelligence techniques that are applicable to Geographic Information Systems (GIS) are examined. Questions involving the performance and modification to the database structure, the definition of spectra in quadtree structures and their use in search heuristics, extension of the knowledge base, and learning algorithm concepts are investigated.

  18. Development of multilayered chitosan-based nanofibers for tissue engineering

    OpenAIRE

    Croisier, Florence; Aqil, Abdelhafid; Detrembleur, Christophe; Jérôme, Christine

    2009-01-01

    By combining electrospinning and layer-by-layer deposition techniques, new porous material scaffolds of multilayered, chitosan-based nanofibers were produced. Layer-by-layer (LBL) is a well-known method for surface coating, based on electrostatic interactions. It enables the controllable deposition of a variety of polyelectrolytes including synthetic and natural materials, with designable layer structure, defined layer thickness and size. Electrospinning (ESP) allows the fabrication of po...

  19. A technique based on droplet evaporation to recognize alcoholic drinks

    Science.gov (United States)

    González-Gutiérrez, Jorge; Pérez-Isidoro, Rosendo; Ruiz-Suárez, J. C.

    2017-07-01

    Chromatography is, at present, the most used technique to determine the purity of alcoholic drinks. This involves a careful separation of the components of the liquid elements. However, since this technique requires sophisticated instrumentation, there are alternative techniques such as conductivity measurements and UV-Vis and infrared spectrometries. We report here a method based on salt-induced crystallization patterns formed during the evaporation of alcoholic drops. We found that droplets of different samples form different structures upon drying, which we characterize by their radial density profiles. We prove that using the dried deposit of a spirit as a control sample, our method allows us to differentiate between pure and adulterated drinks. As a proof of concept, we study tequila.

  20. Function-centered modeling of engineering systems using the goal tree-success tree technique and functional primitives

    International Nuclear Information System (INIS)

    Modarres, Mohammad; Cheon, Se Woo

    1999-01-01

    Most of the complex systems are formed through some hierarchical evolution. Therefore, those systems can be best described through hierarchical frameworks. This paper describes some fundamental attributes of complex physical systems and several hierarchies such as functional, behavioral, goal/condition, and event hierarchies, then presents a function-centered approach to system modeling. Based on the function-centered concept, this paper describes the joint goal tree-success tree (GTST) and the master logic diagram (MLD) as a framework for developing models of complex physical systems. A function-based lexicon for classifying the most common elements of engineering systems for use in the GTST-MLD framework has been proposed. The classification is based on the physical conservation laws that govern the engineering systems. Functional descriptions based on conservation laws provide a simple and rich vocabulary for modeling complex engineering systems

  1. Repository-Based Software Engineering Program: Working Program Management Plan

    Science.gov (United States)

    1993-01-01

    Repository-Based Software Engineering Program (RBSE) is a National Aeronautics and Space Administration (NASA) sponsored program dedicated to introducing and supporting common, effective approaches to software engineering practices. The process of conceiving, designing, building, and maintaining software systems by using existing software assets that are stored in a specialized operational reuse library or repository, accessible to system designers, is the foundation of the program. In addition to operating a software repository, RBSE promotes (1) software engineering technology transfer, (2) academic and instructional support of reuse programs, (3) the use of common software engineering standards and practices, (4) software reuse technology research, and (5) interoperability between reuse libraries. This Program Management Plan (PMP) is intended to communicate program goals and objectives, describe major work areas, and define a management report and control process. This process will assist the Program Manager, University of Houston at Clear Lake (UHCL) in tracking work progress and describing major program activities to NASA management. The goal of this PMP is to make managing the RBSE program a relatively easy process that improves the work of all team members. The PMP describes work areas addressed and work efforts being accomplished by the program; however, it is not intended as a complete description of the program. Its focus is on providing management tools and management processes for monitoring, evaluating, and administering the program; and it includes schedules for charting milestones and deliveries of program products. The PMP was developed by soliciting and obtaining guidance from appropriate program participants, analyzing program management guidance, and reviewing related program management documents.

  2. Autonomous Cryogenic Load Operations: Knowledge-Based Autonomous Test Engineer

    Science.gov (United States)

    Schrading, J. Nicolas

    2013-01-01

    The Knowledge-Based Autonomous Test Engineer (KATE) program has a long history at KSC. Now a part of the Autonomous Cryogenic Load Operations (ACLO) mission, this software system has been sporadically developed over the past 20 years. Originally designed to provide health and status monitoring for a simple water-based fluid system, it was proven to be a capable autonomous test engineer for determining sources of failure in the system. As part of a new goal to provide this same anomaly-detection capability for a complicated cryogenic fluid system, software engineers, physicists, interns and KATE experts are working to upgrade the software capabilities and graphical user interface. Much progress was made during this effort to improve KATE. A display of the entire cryogenic system's graph, with nodes for components and edges for their connections, was added to the KATE software. A searching functionality was added to the new graph display, so that users could easily center their screen on specific components. The GUI was also modified so that it displayed information relevant to the new project goals. In addition, work began on adding new pneumatic and electronic subsystems into the KATE knowledge base, so that it could provide health and status monitoring for those systems. Finally, many fixes for bugs, memory leaks, and memory errors were implemented and the system was moved into a state in which it could be presented to stakeholders. Overall, the KATE system was improved and necessary additional features were added so that a presentation of the program and its functionality in the next few months would be a success.

  3. 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.

  4. Design and manufacturing of patient-specific orthodontic appliances by computer-aided engineering techniques.

    Science.gov (United States)

    Barone, Sandro; Neri, Paolo; Paoli, Alessandro; Razionale, Armando Viviano

    2018-01-01

    Orthodontic treatments are usually performed using fixed brackets or removable oral appliances, which are traditionally made from alginate impressions and wax registrations. Among removable devices, eruption guidance appliances are used for early orthodontic treatments in order to intercept and prevent malocclusion problems. Commercially available eruption guidance appliances, however, are symmetric devices produced using a few standard sizes. For this reason, they are not able to meet all the specific patient's needs since the actual dental anatomies present various geometries and asymmetric conditions. In this article, a computer-aided design-based methodology for the design and manufacturing of a patient-specific eruption guidance appliances is presented. The proposed approach is based on the digitalization of several steps of the overall process: from the digital reconstruction of patients' anatomies to the manufacturing of customized appliances. A finite element model has been developed to evaluate the temporomandibular joint disks stress level caused by using symmetric eruption guidance appliances with different teeth misalignment conditions. The developed model can then be used to guide the design of a patient-specific appliance with the aim at reducing the patient discomfort. At this purpose, two different customization levels are proposed in order to face both arches and single tooth misalignment issues. A low-cost manufacturing process, based on an additive manufacturing technique, is finally presented and discussed.

  5. 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.

  6. A World Wide Web Region-Based Image Search Engine

    DEFF Research Database (Denmark)

    Kompatsiaris, Ioannis; Triantafyllou, Evangelia; Strintzis, Michael G.

    2001-01-01

    In this paper the development of an intelligent image content-based search engine for the World Wide Web is presented. This system will offer a new form of media representation and access of content available in WWW. Information Web Crawlers continuously traverse the Internet and collect images...... information. These features along with additional information such as the URL location and the date of index procedure are stored in a database. The user can access and search this indexed content through the Web with an advanced and user friendly interface. The output of the system is a set of links...

  7. Power system dynamic state estimation using prediction based evolutionary technique

    International Nuclear Information System (INIS)

    Basetti, Vedik; Chandel, Ashwani K.; Chandel, Rajeevan

    2016-01-01

    In this paper, a new robust LWS (least winsorized square) estimator is proposed for dynamic state estimation of a power system. One of the main advantages of this estimator is that it has an inbuilt bad data rejection property and is less sensitive to bad data measurements. In the proposed approach, Brown's double exponential smoothing technique has been utilised for its reliable performance at the prediction step. The state estimation problem is solved as an optimisation problem using a new jDE-self adaptive differential evolution with prediction based population re-initialisation technique at the filtering step. This new stochastic search technique has been embedded with different state scenarios using the predicted state. The effectiveness of the proposed LWS technique is validated under different conditions, namely normal operation, bad data, sudden load change, and loss of transmission line conditions on three different IEEE test bus systems. The performance of the proposed approach is compared with the conventional extended Kalman filter. On the basis of various performance indices, the results thus obtained show that the proposed technique increases the accuracy and robustness of power system dynamic state estimation performance. - Highlights: • To estimate the states of the power system under dynamic environment. • The performance of the EKF method is degraded during anomaly conditions. • The proposed method remains robust towards anomalies. • The proposed method provides precise state estimates even in the presence of anomalies. • The results show that prediction accuracy is enhanced by using the proposed model.

  8. Metabolic engineering of microalgal based biofuel production: prospects and challenges

    Directory of Open Access Journals (Sweden)

    Chiranjib eBanerjee

    2016-03-01

    Full Text Available The current scenario in renewable energy is focused on development of alternate and sustainable energy sources, amongst which microalgae stands as one of the promising feedstock for biofuel production. It is well known that microalgae generate much larger amounts of biofuels in a shorter time than other sources based on plant seeds. However, the greatest challenge in a transition to algae-based biofuel production is the various other complications involved in microalgal cultivation, its harvesting, concentration, drying and lipid extraction. Several green microalgae accumulate lipids, especially triacylglycerols (TAGs, which are main precursors in the production of lipid. The various aspects on metabolic pathway analysis of an oleaginous microalgae i.e. Chlamydomonas reinhardtii have elucidated some novel metabolically important genes and this enhances the lipid production in this microalgae. Adding to it, various other aspects in metabolic engineering using OptFlux and effectual bioprocess design also gives an interactive snapshot of enhancing lipid production which ultimately improvises the oil yield. This article reviews the current status of microalgal based technologies for biofuel production, bioreactor process design, flux analysis and it also provides various strategies to increase lipids accumulation via metabolic engineering.

  9. Surface engineering of graphene-based nanomaterials for biomedical applications.

    Science.gov (United States)

    Shi, Sixiang; Chen, Feng; Ehlerding, Emily B; Cai, Weibo

    2014-09-17

    Graphene-based nanomaterials have attracted tremendous interest over the past decade due to their unique electronic, optical, mechanical, and chemical properties. However, the biomedical applications of these intriguing nanomaterials are still limited due to their suboptimal solubility/biocompatibility, potential toxicity, and difficulties in achieving active tumor targeting, just to name a few. In this Topical Review, we will discuss in detail the important role of surface engineering (i.e., bioconjugation) in improving the in vitro/in vivo stability and enriching the functionality of graphene-based nanomaterials, which can enable single/multimodality imaging (e.g., optical imaging, positron emission tomography, magnetic resonance imaging) and therapy (e.g., photothermal therapy, photodynamic therapy, and drug/gene delivery) of cancer. Current challenges and future research directions are also discussed and we believe that graphene-based nanomaterials are attractive nanoplatforms for a broad array of future biomedical applications.

  10. Characterization techniques for graphene-based materials in catalysis

    Directory of Open Access Journals (Sweden)

    Maocong Hu

    2017-06-01

    Full Text Available Graphene-based materials have been studied in a wide range of applications including catalysis due to the outstanding electronic, thermal, and mechanical properties. The unprecedented features of graphene-based catalysts, which are believed to be responsible for their superior performance, have been characterized by many techniques. In this article, we comprehensively summarized the characterization methods covering bulk and surface structure analysis, chemisorption ability determination, and reaction mechanism investigation. We reviewed the advantages/disadvantages of different techniques including Raman spectroscopy, X-ray photoelectron spectroscopy (XPS, Fourier transform infrared spectroscopy (FTIR and Diffuse Reflectance Fourier Transform Infrared Spectroscopy (DRIFTS, X-Ray diffraction (XRD, X-ray absorption near edge structure (XANES and X-ray absorption fine structure (XAFS, atomic force microscopy (AFM, scanning electron microscopy (SEM, transmission electron microscopy (TEM, high-resolution transmission electron microscopy (HRTEM, ultraviolet-visible spectroscopy (UV-vis, X-ray fluorescence (XRF, inductively coupled plasma mass spectrometry (ICP, thermogravimetric analysis (TGA, Brunauer–Emmett–Teller (BET, and scanning tunneling microscopy (STM. The application of temperature-programmed reduction (TPR, CO chemisorption, and NH3/CO2-temperature-programmed desorption (TPD was also briefly introduced. Finally, we discussed the challenges and provided possible suggestions on choosing characterization techniques. This review provides key information to catalysis community to adopt suitable characterization techniques for their research.

  11. Fractal Image Compression Based on High Entropy Values Technique

    Directory of Open Access Journals (Sweden)

    Douaa Younis Abbaas

    2018-04-01

    Full Text Available There are many attempts tried to improve the encoding stage of FIC because it consumed time. These attempts worked by reducing size of the search pool for pair range-domain matching but most of them led to get a bad quality, or a lower compression ratio of reconstructed image. This paper aims to present a method to improve performance of the full search algorithm by combining FIC (lossy compression and another lossless technique (in this case entropy coding is used. The entropy technique will reduce size of the domain pool (i. e., number of domain blocks based on the entropy value of each range block and domain block and then comparing the results of full search algorithm and proposed algorithm based on entropy technique to see each of which give best results (such as reduced the encoding time with acceptable values in both compression quali-ty parameters which are C. R (Compression Ratio and PSNR (Image Quality. The experimental results of the proposed algorithm proven that using the proposed entropy technique reduces the encoding time while keeping compression rates and reconstruction image quality good as soon as possible.

  12. Chapter VIII. Contributions of propagation techniques and genetic modification to breeding - genetic engineering for disease resistance

    Science.gov (United States)

    Genetic engineering offers an opportunity to develop flower bulb crops with resistance to fungal, viral, and bacterial pathogens. Several of the flower bulb crops, Lilium spp., Gladiolus, Zantedeschia, Muscari, Hyacinthus, Narcissus, Ornithogalum, Iris, and Alstroemeria, have been transformed with t...

  13. Molecular profiling techniques as tools to detect potential unintended effects in genetically engineered maize

    CSIR Research Space (South Africa)

    Barros, E

    2010-05-01

    Full Text Available In the early stages of production and commercialization of foods derived from genetically engineered (GE) plants, international consensus was reached on the principles of food safety evaluation. The concept of substantial equivalence became...

  14. Enhancement of Nanosat Launch Vehicle Booster Main Engine Using 3D Additive Manufacturing Techniques

    Data.gov (United States)

    National Aeronautics and Space Administration — Applying additive manufacturing (AM) technology in development at NASA MSFC to improve a LOX/propylene booster engine for a nanosatellite launch vehicle. This...

  15. Improved Rocket Test Engine Video Recording with Computational Photography and Computer Vision Techniques

    Data.gov (United States)

    National Aeronautics and Space Administration — High energy processes such as rocket engine flight certification ground testing require high-speed, high dynamic range video imaging in order to capture and record...

  16. Improved Rocket Test Engine Video Recording with Computational Photography and Computer Vision Techniques

    Data.gov (United States)

    National Aeronautics and Space Administration — Rocket engine flight certification ground testing requires high-speed video recording that can capture essential information for NASA. This need is particularly true...

  17. Integrated Water Hazards Engineering Based on Mapping, Nature-Based and Technical Solutions

    Science.gov (United States)

    Halbac-Cotoara-Zamfir, Rares; Herban, Sorin; Stolte, Jannes; Bozan, Csaba

    2017-10-01

    Climate change is expected to alter average temperature and precipitation values and to increase the variability of precipitation events, which may lead to even more intense and frequent water hazards. Water hazards engineering is the branch of engineering concerned with the application of scientific and engineering principles for protection of human populations from the effects of water hazards; protection of environments, both local and global, from the potentially deleterious effects of water hazards; and improvement of environmental quality for mitigating the negative effects of water hazards. An integrated approach of water hazards engineering based on mapping, nature-based and technical solutions will constitute a feasible solution in the process of adapting to challenges generated by climate changes worldwide. This paper will debate this concept also providing some examples from several European countries.

  18. Software Engineering Environment for Component-based Design of Embedded Software

    DEFF Research Database (Denmark)

    Guo, Yu

    2010-01-01

    as well as application models in a computer-aided software engineering environment. Furthermore, component models have been realized following carefully developed design patterns, which provide for an efficient and reusable implementation. The components have been ultimately implemented as prefabricated......, validation, and executable code generation for specific hardware platforms. Developing such an environment and the associated tools is a highly complex engineering task. Therefore, this thesis has investigated key design issues and analysed existing platforms supporting model-driven software development...... software technology, which is largely based on informal design methods and manual coding techniques. That is why it is necessary to develop new design methods and tools that will eventually help improve existing practices. These considerations have motivated the development of the framework -- Component...

  19. Demonstration of Novel Sampling Techniques for Measurement of Turbine Engine Volatile and Non-Volatile Particulate Matter (PM) Emissions

    Science.gov (United States)

    2016-09-01

    only), which includes hot and cold dilution with an evaporator , and finally to instrumentation for particle number measurements . However, several...DC, CDP and plume BC was measure using a Laser Induced Incandescence (LII) instrument. Data for the BC LII mass measurements at the plume and...AFRL-RQ-WP-TR-2016-0131 DEMONSTRATION OF NOVEL SAMPLING TECHNIQUES FOR MEASUREMENT OF TURBINE ENGINE VOLATILE AND NON-VOLATILE PARTICULATE

  20. Gendered practices of constructing an engineering identity in a problem-based learning environment

    DEFF Research Database (Denmark)

    Du, Xiangyun

    2006-01-01

    of an engineering identity with masculinity and the culturally defined engineering competencies leads to different learning experiences for male and female students. The nature of hard-core engineering subjects, based on male interests, privileges men and acts as a barrier to women. The masculine culture...... in engineering communities of practice involves more effort in identity management for women students than their male peers.......This article examines the learning experiences of engineering students of both genders in a problem-based and project-organized learning environment (PBL) at a Danish university. This study relates an amalgam of theories on learning and gender to the context of engineering education. Based on data...

  1. Using formal methods to teach software engineering: a tool-based approach

    OpenAIRE

    Ciancarini, P.; Mascolo, C.

    1998-01-01

    In this paper we describe and review the course plan and syllabus we use in a course on formal methods in software engineering currently included in the degree in Informatics of the Faculty of Sciences at the University of Bologna. The course matches the theory of formal methods with their practice based on actual tool usage. In fact, the course is centered upon a project whose main goal is to let students learn some formal specification techniques, all supported by specific tools. The studen...

  2. Optimal Tuner Selection for Kalman Filter-Based Aircraft Engine Performance Estimation

    Science.gov (United States)

    Simon, Donald L.; Garg, Sanjay

    2010-01-01

    A linear point design methodology for minimizing the error in on-line Kalman filter-based aircraft engine performance estimation applications is presented. This technique specifically addresses the underdetermined estimation problem, where there are more unknown parameters than available sensor measurements. A systematic approach is applied to produce a model tuning parameter vector of appropriate dimension to enable estimation by a Kalman filter, while minimizing the estimation error in the parameters of interest. Tuning parameter selection is performed using a multi-variable iterative search routine which seeks to minimize the theoretical mean-squared estimation error. This paper derives theoretical Kalman filter estimation error bias and variance values 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 conventional approach of tuner selection. Experimental simulation results are found to be in agreement with theoretical predictions. The new methodology is shown to yield a significant improvement in on-line engine performance estimation accuracy

  3. 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.

  4. MPPT Technique Based on Current and Temperature Measurements

    OpenAIRE

    Vicente, Eduardo Moreira; Moreno, Robson Luiz; Ribeiro, Enio Roberto

    2015-01-01

    This paper presents a new maximum power point tracking (MPPT) method based on the measurement of temperature and short-circuit current, in a simple and efficient approach. These measurements, which can precisely define the maximum power point (MPP), have not been used together in other existing techniques. The temperature is measured with a low cost sensor and the solar irradiance is estimated through the relationship of the measured short-circuit current and its reference. Fast tracking spee...

  5. Cooperative Technique Based on Sensor Selection in Wireless Sensor Network

    OpenAIRE

    ISLAM, M. R.; KIM, J.

    2009-01-01

    An energy efficient cooperative technique is proposed for the IEEE 1451 based Wireless Sensor Networks. Selected numbers of Wireless Transducer Interface Modules (WTIMs) are used to form a Multiple Input Single Output (MISO) structure wirelessly connected with a Network Capable Application Processor (NCAP). Energy efficiency and delay of the proposed architecture are derived for different combination of cluster size and selected number of WTIMs. Optimized constellation parameters are used for...

  6. Introduction of Functional Structures in Nano-Scales into Engineering Polymer Films Using Radiation Technique

    International Nuclear Information System (INIS)

    Maekawa, Y.

    2010-01-01

    Introduction of functional regions in nanometer scale in polymeric films using γ-rays, EB, and ion beams are proposed. Two approaches to build nano-scale functional domains in polymer substrates are proposed: 1) Radiation-induced grafting to transfer nano-scale polymer crystalline structures (morphology), acting as a nano-template, to nano-scale graft polymer regions. The obtained polymers with nano structures can be applied to high performance polymer membranes. 2) Fabrication of nanopores and functional domains in engineering plastic films using ion beams, which deposit the energy in very narrow region of polymer films. Hydrophilic grafting polymers are introduced into hydrophobic fluorinated polymers, cross-linked PTFE (cPTFE) and aromatic hydrocarbon polymer, poly(ether ether ketone (PEEK), which is known to have lamella and crystallite in the polymer films. Then, the hierarchical structures of graft domains are analyzed by a small angle neutron scattering (SANS) experiment. From these analyses, the different structures and the different formation of graft domains were observed in fluorinated and hydrocarbon polymer substrates. the grafted domains in the cPTFE film, working as an ion channel, grew as covering the crystallite and the size of domain seems to be similar to that of crystallite. On the other hand, the PEEK-based PEM has a smaller domain size and it seems to grow independently on the crystallites of PEEK substrate. For nano-fabrication of polymer films using heavy ion beams, the energy distribution in radial direction, which is perpendicular to ion trajectory, is mainly concerned. For penumbra, we re-estimated effective radius of penumbra, in which radiation induced grafting took place, for several different ion beams. We observed the different diameters of the ion channels consisting of graft polymers. The channel sizes were quite in good agreement with the effective penumbra which possess the absorption doses more than 1 kGy. (author)

  7. Data configurations in railway signalling engineering - an application of enterprise systems techniques

    Science.gov (United States)

    Chen, Xiangxian; Guan, Aiai; Qiu, Xinxi; Huang, Hai; Liu, Jiquan; Duan, Huilong

    2013-08-01

    Railway signalling system is a safety-critical system to ensure railway safety and its development cost is huge. It is of great economic value to apply the generic signalling systems in different environments through configuration of different application data. In this paper, a new method to configure the application data completely and accurately is illustrated; in particular, a technique called automatic generation technology is introduced to automatically configure the functional logic of safety-critical systems, i.e. computer-based interlocking (CBI) system and automatic train protection (ATP) system. All of the application data are collected from the workflow among various departments through the enterprise system (ES). Some application data are represented by models employing automatic generation technology, and the functional logic is then obtained through analysis using these models. A configuration platform based on the ES is developed in which both the efficiency and accuracy of the application data configuration are significantly improved. In addition, it is capable of reducing human errors to a maximal extent.

  8. Tissue Engineering Bionanocomposites Based on Poly(propylene fumarate

    Directory of Open Access Journals (Sweden)

    Ana M. Diez-Pascual

    2017-06-01

    Full Text Available Poly(propylene fumarate (PPF is a linear and unsaturated copolyester based on fumaric acid that has been widely investigated for tissue engineering applications in recent years due to its tailorable mechanical performance, adjustable biodegradability and exceptional biocompatibility. In order to improve its mechanical properties and spread its range of practical applications, novel approaches need to be developed such as the incorporation of fillers or polymer blending. Thus, PPF-based bionanocomposites reinforced with different amounts of single-walled carbon nanotubes (SWCNT, multi-walled carbon nanotubes (MWCNT, graphene oxide nanoribbons (GONR, graphite oxide nanoplatelets (GONP, polyethylene glycol-functionalized graphene oxide (PEG-GO, polyethylene glycol-grafted boron nitride nanotubes (PEG-g-BNNTs and hydroxyapatite (HA nanoparticles were synthesized via sonication and thermal curing, and their morphology, biodegradability, cytotoxicity, thermal, rheological, mechanical and antibacterial properties were investigated. An increase in the level of hydrophilicity, biodegradation rate, stiffness and strength was found upon increasing nanofiller loading. The nanocomposites retained enough rigidity and strength under physiological conditions to provide effective support for bone tissue formation, showed antibacterial activity against Gram-positive and Gram-negative bacteria, and did not induce toxicity on human dermal fibroblasts. These novel biomaterials demonstrate great potential to be used for bone tissue engineering applications.

  9. Internet-based dimensional verification system for reverse engineering processes

    International Nuclear Information System (INIS)

    Song, In Ho; Kim, Kyung Don; Chung, Sung Chong

    2008-01-01

    This paper proposes a design methodology for a Web-based collaborative system applicable to reverse engineering processes in a distributed environment. By using the developed system, design reviewers of new products are able to confirm geometric shapes, inspect dimensional information of products through measured point data, and exchange views with other design reviewers on the Web. In addition, it is applicable to verifying accuracy of production processes by manufacturing engineers. Functional requirements for designing this Web-based dimensional verification system are described in this paper. ActiveX-server architecture and OpenGL plug-in methods using ActiveX controls realize the proposed system. In the developed system, visualization and dimensional inspection of the measured point data are done directly on the Web: conversion of the point data into a CAD file or a VRML form is unnecessary. Dimensional verification results and design modification ideas are uploaded to markups and/or XML files during collaboration processes. Collaborators review the markup results created by others to produce a good design result on the Web. The use of XML files allows information sharing on the Web to be independent of the platform of the developed system. It is possible to diversify the information sharing capability among design collaborators. Validity and effectiveness of the developed system has been confirmed by case studies

  10. Internet-based dimensional verification system for reverse engineering processes

    Energy Technology Data Exchange (ETDEWEB)

    Song, In Ho [Ajou University, Suwon (Korea, Republic of); Kim, Kyung Don [Small Business Corporation, Suwon (Korea, Republic of); Chung, Sung Chong [Hanyang University, Seoul (Korea, Republic of)

    2008-07-15

    This paper proposes a design methodology for a Web-based collaborative system applicable to reverse engineering processes in a distributed environment. By using the developed system, design reviewers of new products are able to confirm geometric shapes, inspect dimensional information of products through measured point data, and exchange views with other design reviewers on the Web. In addition, it is applicable to verifying accuracy of production processes by manufacturing engineers. Functional requirements for designing this Web-based dimensional verification system are described in this paper. ActiveX-server architecture and OpenGL plug-in methods using ActiveX controls realize the proposed system. In the developed system, visualization and dimensional inspection of the measured point data are done directly on the Web: conversion of the point data into a CAD file or a VRML form is unnecessary. Dimensional verification results and design modification ideas are uploaded to markups and/or XML files during collaboration processes. Collaborators review the markup results created by others to produce a good design result on the Web. The use of XML files allows information sharing on the Web to be independent of the platform of the developed system. It is possible to diversify the information sharing capability among design collaborators. Validity and effectiveness of the developed system has been confirmed by case studies

  11. Internet based remote cooperative engineering system for NSSS system design

    International Nuclear Information System (INIS)

    Kim, Y. S.; Lee, S. L.

    2000-01-01

    Implementation of information technology system through the nuclear power plant life cycle which covers site selection, design, construction, operation and decommission has been suggested continually by the reports or guidelines from NIRMA, INPO, NUMARC, USNRC and EPRI since late 1980's, and some of it has been actually implemented and applied partially to the practical design process. However, for the NSSS system design, a high level activity of nuclear power plant design phase, none of the effects has been reported with regard to implementing the information system. In Korea, KAERI studied NuIDEAS(Nuclear Integrated Database and Design Advancement System) in 1995, and KAERI (Korea Electric Power Research Institute) worked with CENP (Combustion Engineering Nuclear Power) for KNGR IMS(Information Management System) in 1997 as trials to adopt information system for NSSS system design. In this paper, after reviewing the pre-studied two information system, we introduce implementation of the information system for NSSS system design which is compatible with the on-going design works and can be used as means of concurrent engineering through internet. With this electronic design system, we expect increase of the design efficiency and productivity by switching from hard copy based design flow to internet based system. In addition, reliability and traceability of the design data is highly elevated by containing the native document file together with all the review, comment and resolution history in one database

  12. 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.

  13. An Image Morphing Technique Based on Optimal Mass Preserving Mapping

    Science.gov (United States)

    Zhu, Lei; Yang, Yan; Haker, Steven; Tannenbaum, Allen

    2013-01-01

    Image morphing, or image interpolation in the time domain, deals with the metamorphosis of one image into another. In this paper, a new class of image morphing algorithms is proposed based on the theory of optimal mass transport. The L2 mass moving energy functional is modified by adding an intensity penalizing term, in order to reduce the undesired double exposure effect. It is an intensity-based approach and, thus, is parameter free. The optimal warping function is computed using an iterative gradient descent approach. This proposed morphing method is also extended to doubly connected domains using a harmonic parameterization technique, along with finite-element methods. PMID:17547128

  14. A Linguistic Evaluation of Rule-Based, Phrase-Based, and Neural MT Engines

    Directory of Open Access Journals (Sweden)

    Burchardt Aljoscha

    2017-06-01

    Full Text Available In this paper, we report an analysis of the strengths and weaknesses of several Machine Translation (MT engines implementing the three most widely used paradigms. The analysis is based on a manually built test suite that comprises a large range of linguistic phenomena. Two main observations are on the one hand the striking improvement of an commercial online system when turning from a phrase-based to a neural engine and on the other hand that the successful translations of neural MT systems sometimes bear resemblance with the translations of a rule-based MT system.

  15. A DIFFERENT WEB-BASED GEOCODING SERVICE USING FUZZY TECHNIQUES

    Directory of Open Access Journals (Sweden)

    P. Pahlavani

    2015-12-01

    Full Text Available Geocoding – the process of finding position based on descriptive data such as address or postal code - is considered as one of the most commonly used spatial analyses. Many online map providers such as Google Maps, Bing Maps and Yahoo Maps present geocoding as one of their basic capabilities. Despite the diversity of geocoding services, users usually face some limitations when they use available online geocoding services. In existing geocoding services, proximity and nearness concept is not modelled appropriately as well as these services search address only by address matching based on descriptive data. In addition there are also some limitations in display searching results. Resolving these limitations can enhance efficiency of the existing geocoding services. This paper proposes the idea of integrating fuzzy technique with geocoding process to resolve these limitations. In order to implement the proposed method, a web-based system is designed. In proposed method, nearness to places is defined by fuzzy membership functions and multiple fuzzy distance maps are created. Then these fuzzy distance maps are integrated using fuzzy overlay technique for obtain the results. Proposed methods provides different capabilities for users such as ability to search multi-part addresses, searching places based on their location, non-point representation of results as well as displaying search results based on their priority.

  16. Using the ultrasound and instrumented indentation techniques to measure the elastic modulus of engineering materials

    International Nuclear Information System (INIS)

    Meza, J. M.; Franco, E. E.; Farias, M. C. M.; Buiochi, F.; Souza, R. M.; Cruz, J.

    2008-01-01

    Currently, the acoustic and nano indentation techniques are two of the most used techniques for materials elastic modulus measurement. In this article fundamental principles and limitations of both techniques are shown and discussed. Last advances in nano indentation technique are also reviewed. an experimental study in ceramic, metallic, composite and single crystals was also done. Results shown that ultrasonic technique is capable to provide results in agreement with those reported in literature. However, ultrasonic technique does not allow measuring the elastic modulus of some small samples and single crystals. On the other hand, the nano indentation technique estimates the elastic modulus values in reasonable agreement with those measured by acoustic methods, particularly in amorphous materials, while in some policristaline materials some deviation from expected values was obtained. (Author) 29 refs

  17. Realizing parameterless automatic classification of remote sensing imagery using ontology engineering and cyberinfrastructure techniques

    Science.gov (United States)

    Sun, Ziheng; Fang, Hui; Di, Liping; Yue, Peng

    2016-09-01

    It was an untouchable dream for remote sensing experts to realize total automatic image classification without inputting any parameter values. Experts usually spend hours and hours on tuning the input parameters of classification algorithms in order to obtain the best results. With the rapid development of knowledge engineering and cyberinfrastructure, a lot of data processing and knowledge reasoning capabilities become online accessible, shareable and interoperable. Based on these recent improvements, this paper presents an idea of parameterless automatic classification which only requires an image and automatically outputs a labeled vector. No parameters and operations are needed from endpoint consumers. An approach is proposed to realize the idea. It adopts an ontology database to store the experiences of tuning values for classifiers. A sample database is used to record training samples of image segments. Geoprocessing Web services are used as functionality blocks to finish basic classification steps. Workflow technology is involved to turn the overall image classification into a total automatic process. A Web-based prototypical system named PACS (Parameterless Automatic Classification System) is implemented. A number of images are fed into the system for evaluation purposes. The results show that the approach could automatically classify remote sensing images and have a fairly good average accuracy. It is indicated that the classified results will be more accurate if the two databases have higher quality. Once the experiences and samples in the databases are accumulated as many as an expert has, the approach should be able to get the results with similar quality to that a human expert can get. Since the approach is total automatic and parameterless, it can not only relieve remote sensing workers from the heavy and time-consuming parameter tuning work, but also significantly shorten the waiting time for consumers and facilitate them to engage in image

  18. Rapid manufacturing techniques for the tissue engineering of human heart valves.

    Science.gov (United States)

    Lueders, Cora; Jastram, Ben; Hetzer, Roland; Schwandt, Hartmut

    2014-10-01

    Three-dimensional (3D) printing technologies have reached a level of quality that justifies considering rapid manufacturing for medical applications. Herein, we introduce a new approach using 3D printing to simplify and improve the fabrication of human heart valve scaffolds by tissue engineering (TE). Custom-made human heart valve scaffolds are to be fabricated on a selective laser-sintering 3D printer for subsequent seeding with vascular cells from human umbilical cords. The scaffolds will be produced from resorbable polymers that must feature a number of specific properties: the structure, i.e. particle granularity and shape, and thermic properties must be feasible for the printing process. They must be suitable for the cell-seeding process and at the same time should be resorbable. They must be applicable for implementation in the human body and flexible enough to support the full functionality of the valve. The research focuses mainly on the search for a suitable scaffold material that allows the implementation of both the printing process to produce the scaffolds and the cell-seeding process, while meeting all of the above requirements. Computer tomographic data from patients were transformed into a 3D data model suitable for the 3D printer. Our current activities involve various aspects of the printing process, material research and the implementation of the cell-seeding process. Different resorbable polymeric materials have been examined and used to fabricate heart valve scaffolds by rapid manufacturing. Human vascular cells attached to the scaffold surface should migrate additionally into the inner structure of the polymeric samples. The ultimate intention of our approach is to establish a heart valve fabrication process based on 3D rapid manufacturing and TE. Based on the computer tomographic data of a patient, a custom-made scaffold for a valve will be produced on a 3D printer and populated preferably by autologous cells. The long-term goal is to support

  19. 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....

  20. Engineering-Based Thermal CFD Simulations on Massive Parallel Systems

    KAUST Repository

    Frisch, Jérôme

    2015-05-22

    The development of parallel Computational Fluid Dynamics (CFD) codes is a challenging task that entails efficient parallelization concepts and strategies in order to achieve good scalability values when running those codes on modern supercomputers with several thousands to millions of cores. In this paper, we present a hierarchical data structure for massive parallel computations that supports the coupling of a Navier–Stokes-based fluid flow code with the Boussinesq approximation in order to address complex thermal scenarios for energy-related assessments. The newly designed data structure is specifically designed with the idea of interactive data exploration and visualization during runtime of the simulation code; a major shortcoming of traditional high-performance computing (HPC) simulation codes. We further show and discuss speed-up values obtained on one of Germany’s top-ranked supercomputers with up to 140,000 processes and present simulation results for different engineering-based thermal problems.

  1. SKILLS-BASED ECLECTIC TECHNIQUES MATRIX FOR ELT MICROTEACHINGS

    Directory of Open Access Journals (Sweden)

    İskender Hakkı Sarıgöz

    2016-10-01

    Full Text Available Foreign language teaching undergoes constant changes due to the methodological improvement. This progress may be examined in two parts. They are the methods era and the post-methods era. It is not pragmatic today to propose a particular language teaching method and its techniques for all purposes. The holistic inflexibility of mid-century methods has long gone. In the present day, constructivist foreign language teaching trends attempt to see the learner as a whole person and an individual who may be different from the other students in many respects. At the same time, the individual differences should not keep the learners away from group harmony. For this reason, current teacher training programs require eclectic teaching matrixes for unit design considering the mixed ability student groups. These matrixes can be prepared in a multidimensional fashion because there are many functional techniques in different methods and other new techniques to be created by instructors freely in accordance with the teaching aims. The hypothesis in this argument is that the collection of foreign language teaching techniques compiled in ELT microteachings for a particular group of learners has to be arranged eclectically in order to update the teaching process. Nevertheless, designing a teaching format of this sort is a demanding and highly criticized task. This study briefly argues eclecticism in language-skills based methodological struggle from the perspective of ELT teacher education.

  2. Novel optical password security technique based on optical fractal synthesizer

    Science.gov (United States)

    Wu, Kenan; Hu, Jiasheng; Wu, Xu

    2009-06-01

    A novel optical security technique for safeguarding user passwords based on an optical fractal synthesizer is proposed. A validating experiment has been carried out. In the proposed technique, a user password is protected by being converted to a fractal image. When a user sets up a new password, the password is transformed into a fractal pattern, and the fractal pattern is stored in authority. If the user is online-validated, his or her password is converted to a fractal pattern again to compare with the previous stored fractal pattern. The converting process is called the fractal encoding procedure, which consists of two steps. First, the password is nonlinearly transformed to get the parameters for the optical fractal synthesizer. Then the optical fractal synthesizer is operated to generate the output fractal image. The experimental result proves the validity of our method. The proposed technique bridges the gap between digital security systems and optical security systems and has many advantages, such as high security level, convenience, flexibility, hyper extensibility, etc. This provides an interesting optical security technique for the protection of digital passwords.

  3. Micro-cogeneration units based on Stirling engine for heating and their real operation

    Science.gov (United States)

    Čierny, Jaroslav; Patsch, Marek

    2014-08-01

    This article was deal with micro-cogeneration units based on Stirling engine. We watched problematic of real working Stirling engine. The article also contain hookup of unit constructed at University of Zilina.

  4. Efficient techniques for wave-based sound propagation in interactive applications

    Science.gov (United States)

    Mehra, Ravish

    -driven, rotating or time-varying directivity function at runtime. Unlike previous approaches, the listener directivity approach can be used to compute spatial audio (3D audio) for a moving, rotating listener at interactive rates. Lastly, we propose an efficient GPU-based time-domain solver for the wave equation that enables wave simulation up to the mid-frequency range in tens of minutes on a desktop computer. It is demonstrated that by carefully mapping all the components of the wave simulator to match the parallel processing capabilities of the graphics processors, significant improvement in performance can be achieved compared to the CPU-based simulators, while maintaining numerical accuracy. We validate these techniques with offline numerical simulations and measured data recorded in an outdoor scene. We present results of preliminary user evaluations conducted to study the impact of these techniques on user's immersion in virtual environment. We have integrated these techniques with the Half-Life 2 game engine, Oculus Rift head-mounted display, and Xbox game controller to enable users to experience high-quality acoustics effects and spatial audio in the virtual environment.

  5. Efficient Identification Using a Prime-Feature-Based Technique

    DEFF Research Database (Denmark)

    Hussain, Dil Muhammad Akbar; Haq, Shaiq A.; Valente, Andrea

    2011-01-01

    Identification of authorized train drivers through biometrics is a growing area of interest in locomotive radio remote control systems. The existing technique of password authentication is not very reliable and potentially unauthorized personnel may also operate the system on behalf of the operator....... Fingerprint identification system, implemented on PC/104 based real-time systems, can accurately identify the operator. Traditionally, the uniqueness of a fingerprint is determined by the overall pattern of ridges and valleys as well as the local ridge anomalies e.g., a ridge bifurcation or a ridge ending...... in this paper. The technique involves identifying the most prominent feature of the fingerprint and searching only for that feature in the database to expedite the search process. The proposed architect provides efficient matching process and indexing feature for identification is unique....

  6. Adaptive differential correspondence imaging based on sorting technique

    Directory of Open Access Journals (Sweden)

    Heng Wu

    2017-04-01

    Full Text Available We develop an adaptive differential correspondence imaging (CI method using a sorting technique. Different from the conventional CI schemes, the bucket detector signals (BDS are first processed by a differential technique, and then sorted in a descending (or ascending order. Subsequently, according to the front and last several frames of the sorted BDS, the positive and negative subsets (PNS are created by selecting the relative frames from the reference detector signals. Finally, the object image is recovered from the PNS. Besides, an adaptive method based on two-step iteration is designed to select the optimum number of frames. To verify the proposed method, a single-detector computational ghost imaging (GI setup is constructed. We experimentally and numerically compare the performance of the proposed method with different GI algorithms. The results show that our method can improve the reconstruction quality and reduce the computation cost by using fewer measurement data.

  7. Wear Detection of Drill Bit by Image-based Technique

    Science.gov (United States)

    Sukeri, Maziyah; Zulhilmi Paiz Ismadi, Mohd; Rahim Othman, Abdul; Kamaruddin, Shahrul

    2018-03-01

    Image processing for computer vision function plays an essential aspect in the manufacturing industries for the tool condition monitoring. This study proposes a dependable direct measurement method to measure the tool wear using image-based analysis. Segmentation and thresholding technique were used as the means to filter and convert the colour image to binary datasets. Then, the edge detection method was applied to characterize the edge of the drill bit. By using cross-correlation method, the edges of original and worn drill bits were correlated to each other. Cross-correlation graphs were able to detect the difference of the worn edge despite small difference between the graphs. Future development will focus on quantifying the worn profile as well as enhancing the sensitivity of the technique.

  8. Underwater Time Service and Synchronization Based on Time Reversal Technique

    Science.gov (United States)

    Lu, Hao; Wang, Hai-bin; Aissa-El-Bey, Abdeldjalil; Pyndiah, Ramesh

    2010-09-01

    Real time service and synchronization are very important to many underwater systems. But the time service and synchronization in existence cannot work well due to the multi-path propagation and random phase fluctuation of signals in the ocean channel. The time reversal mirror technique can realize energy concentration through self-matching of the ocean channel and has very good spatial and temporal focusing properties. Based on the TRM technique, we present the Time Reversal Mirror Real Time service and synchronization (TRMRT) method which can bypass the processing of multi-path on the server side and reduce multi-path contamination on the client side. So TRMRT can improve the accuracy of time service. Furthermore, as an efficient and precise method of time service, TRMRT could be widely used in underwater exploration activities and underwater navigation and positioning systems.

  9. Standardized fluoroscopy-based technique to measure intraoperative cup anteversion.

    Science.gov (United States)

    Zingg, Matthieu; Boudabbous, Sana; Hannouche, Didier; Montet, Xavier; Boettner, Friedrich

    2017-10-01

    Direct anterior approach (DAA) with the patient lying supine has facilitated the use of intraoperative fluoroscopy and allows for standardized positioning of the patient. The current study presents a new technique to measure acetabular component anteversion using intraoperative fluoroscopy. The current paper describes a mathematical formula to calculate true acetabular component anteversion based on the acetabular component abduction angle and the c-arm tilt angle (CaT). The CaT is determined by tilting the c-arm until an external pelvic oblique radiograph with the equatorial plane of the acetabular component perpendicular to the fluoroscopy receptor is obtained. CaT is determined by direct reading on the C-arm device. The technique was validated using a radiopaque synbone model comparing the described technique to computed tomography anteversion measurement. The experiment was repeated 25 times. The difference in anteversion between the two measuring techniques was on average 0.2° (range -3.0-3.1). The linear regression coefficients evaluating the agreement between the experimental and control methods were 0.99 (95%CI 0.88-1.10, p < 0.001) and 0.33 (95%CI -1.53-2.20, p = 0.713) for the slope and intercept, respectively. The current study confirms that the described three-step c-arm acetabular cup measuring technique can reproducibly and reliably assess acetabular component anteversion in the supine position, as compared to CT-imaging. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2307-2312, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  10. Engineering excitonic dynamics and environmental stability of post-transition metal chalcogenides by pyridine functionalization technique.

    Science.gov (United States)

    Meng, Xiuqing; Pant, Anupum; Cai, Hui; Kang, Jun; Sahin, Hasan; Chen, Bin; Wu, Kedi; Yang, Sijie; Suslu, Aslihan; Peeters, F M; Tongay, Sefaattin

    2015-10-28

    Owing to their strong photon emission, low excitonic binding energies, and nearly-ideal band offset values for water splitting reactions, direct gap quasi-2D gallium chalcogenides are potential candidates for applications in energy harvesting, optoelectronics, and photonics. Unlike other 2D materials systems, chemical functionalization of gallium chalcogenides is still at its seminal stages. Here, we propose vapor phase pyridine intercalation technique to manipulate optical properties of gallium chalcogenides. After functionalization, the excitonic dynamics of quasi-2D GaSe change significantly as evidenced by an increase in integrated PL intensity and emergence of a new emission feature that is below the band edge. Based on our DFT calculations, we attribute these to formation of bound exciton complexes at the trap sites introduced by chemical reaction between pyridine and GaSe. On the contrary, pyridine functionalization does not impact the optical properties of GaTe, instead treats GaTe surface to prevent oxidization of tellurium atoms. Overall, results suggest novel ways to control properties of gallium chalcogenides on demand and unleash their full potential for a range of applications in photonics and optoelectronics.

  11. Developing Engineering Students’ Understanding of Sustainability Using Project Based Learning

    Directory of Open Access Journals (Sweden)

    Margaret Jollands

    2013-11-01

    Full Text Available Project based learning (PjBL can be an effective approach to developing graduate attributes, but it depends on how it is implemented. Chemical Engineering of RMIT University has a stream of PjBL subjects from first to final year. The projects are incrementally more complex but have the same goal: to choose a best process design, using management decision making tools to justify their choices. The tools include GEMI Metrics NavigatorTM. This paper reports an evaluation of whether students’ understanding of sustainability is enhanced by undertaking multiple projects, as well as use of sophisticated analysis tools. Student learning outcomes from intermediate and final subjects were compared using ConceptMaps and a focus group. The students’ understanding of sustainability increased substantially from 2nd to final year, similar to results reported in European studies. The spread of results was broad, attributed to range of student ability and differences between student cohorts. Development of understanding of sustainability was attributed to undertaking multiple projects and use of spread-sheeting tools. Use of the GEMI tool was identified as facilitating application of sustainability principles to process design decisions. Concept maps are a useful way to evaluate innovations in teaching sustainable engineering.

  12. Thermoelectric properties of an interacting quantum dot based heat engine

    Science.gov (United States)

    Erdman, Paolo Andrea; Mazza, Francesco; Bosisio, Riccardo; Benenti, Giuliano; Fazio, Rosario; Taddei, Fabio

    2017-06-01

    We study the thermoelectric properties and heat-to-work conversion performance of an interacting, multilevel quantum dot (QD) weakly coupled to electronic reservoirs. We focus on the sequential tunneling regime. The dynamics of the charge in the QD is studied by means of master equations for the probabilities of occupation. From here we compute the charge and heat currents in the linear response regime. Assuming a generic multiterminal setup, and for low temperatures (quantum limit), we obtain analytical expressions for the transport coefficients which account for the interplay between interactions (charging energy) and level quantization. In the case of systems with two and three terminals we derive formulas for the power factor Q and the figure of merit Z T for a QD-based heat engine, identifying optimal working conditions which maximize output power and efficiency of heat-to-work conversion. Beyond the linear response we concentrate on the two-terminal setup. We first study the thermoelectric nonlinear coefficients assessing the consequences of large temperature and voltage biases, focusing on the breakdown of the Onsager reciprocal relation between thermopower and Peltier coefficient. We then investigate the conditions which optimize the performance of a heat engine, finding that in the quantum limit output power and efficiency at maximum power can almost be simultaneously maximized by choosing appropriate values of electrochemical potential and bias voltage. At last we study how energy level degeneracy can increase the output power.

  13. Case-based reasoning support for engineering design

    Science.gov (United States)

    Lees, Brian; Hamza, Meer; Irgens, Chris

    2000-10-01

    The potential application of case-based reasoning (CBR) in design support is illustrated through examples drawn from research at the University of Paisley, demonstrating the suitability of CBR for different aspects of design, different problem areas, and different design goals. A quality advisory system has been developed for the early stages of mechanical engineering design, the aim of which is to provide quality advice in a variant design situation. In the domain of software engineering CBR has been applied to advise on which metrics are appropriate fora assessing the quality of the software currently under design. The system integrates CBR with concepts from quality function deployment (QFD) and incorporates a case library holding past software quality histories. CBR has been applied in support of conceptual design: to capture detailed design histories by monitoring designer actions, and thereby support design reuse through the evaluation of designs, through the provision of query, browsing and replay facilities. The resulting system is aimed to support the design of safety critical systems, by assisting in the construction of safety arguments, and cooperative design.

  14. Effects of processing parameters in thermally induced phase separation technique on porous architecture of scaffolds for bone tissue engineering.

    Science.gov (United States)

    Akbarzadeh, Rosa; Yousefi, Azizeh-Mitra

    2014-08-01

    Tissue engineering makes use of 3D scaffolds to sustain three-dimensional growth of cells and guide new tissue formation. To meet the multiple requirements for regeneration of biological tissues and organs, a wide range of scaffold fabrication techniques have been developed, aiming to produce porous constructs with the desired pore size range and pore morphology. Among different scaffold fabrication techniques, thermally induced phase separation (TIPS) method has been widely used in recent years because of its potential to produce highly porous scaffolds with interconnected pore morphology. The scaffold architecture can be closely controlled by adjusting the process parameters, including polymer type and concentration, solvent composition, quenching temperature and time, coarsening process, and incorporation of inorganic particles. The objective of this review is to provide information pertaining to the effect of these parameters on the architecture and properties of the scaffolds fabricated by the TIPS technique. © 2014 Wiley Periodicals, Inc.

  15. Effective Design of Educational Virtual Reality Applications for Medicine Using Knowledge-Engineering Techniques

    Science.gov (United States)

    Górski, Filip; Bun, Pawel; Wichniarek, Radoslaw; Zawadzki, Przemyslaw; Hamrol, Adam

    2017-01-01

    Effective medical and biomedical engineering education is an important problem. Traditional methods are difficult and costly. That is why Virtual Reality is often used for that purpose. Educational medical VR is a well-developed IT field, with many available hardware and software solutions. Current solutions are prepared without methodological…

  16. The rotator cuff: from bench to bedside. Developments in tissue engineering, surgical techniques and pathogenetic factors

    NARCIS (Netherlands)

    Longo, U.G.

    2012-01-01

    This thesis originates from the difficulties in the management of patients with rotator cuff tears. Since tendon healing rate is relatively slow compared with other connective tissues, we reviewed the available literature on tissue engineered biological augmentation for tendon healing, including

  17. Photolithography and micromolding techniques for the realization of 3D polycaprolactone scaffolds for tissue engineering applications

    KAUST Repository

    Limongi, Tania

    2015-06-01

    Material science, cell biology, and engineering are all part of the research field of tissue engineering. It is the application of knowledge, methods and instrumentations of engineering and life science to the development of biocompatible solutions for repair and/or replace tissues and damaged organs. Last generation microfabrication technologies utilizing natural and synthetic biomaterials allow the realization of scaffolds resembling tissue-like structures as skin, brain, bones, muscles, cartilage and blood vessels. In this work we describe an effective and simple micromolding fabrication process allowing the realization of 3D polycaprolactone (PCL) scaffold for human neural stem cells (hNSC) culture. Scanning Electron Microscopy has been used to investigate the micro and nano features characterizing the surface of the device. Immunofluorescence analysis showed how, after seeding cells onto the substrate, healthy astrocytes grew up in a well-organized 3D network. Thus, we proposed this effective fabrication method for the production of nanopatterned PCL pillared scaffold providing a biomimetic environment for the growth of hNSC, a promising and efficient means for future applications in tissue engineering and regenerative medicine.

  18. Strain-engineered MOSFETs

    CERN Document Server

    Maiti, CK

    2012-01-01

    Currently strain engineering is the main technique used to enhance the performance of advanced silicon-based metal-oxide-semiconductor field-effect transistors (MOSFETs). Written from an engineering application standpoint, Strain-Engineered MOSFETs introduces promising strain techniques to fabricate strain-engineered MOSFETs and to methods to assess the applications of these techniques. The book provides the background and physical insight needed to understand new and future developments in the modeling and design of n- and p-MOSFETs at nanoscale. This book focuses on recent developments in st

  19. Ultra-fast quantitative imaging using ptychographic iterative engine based digital micro-mirror device

    Science.gov (United States)

    Sun, Aihui; Tian, Xiaolin; Kong, Yan; Jiang, Zhilong; Liu, Fei; Xue, Liang; Wang, Shouyu; Liu, Cheng

    2018-01-01

    As a lensfree imaging technique, ptychographic iterative engine (PIE) method can provide both quantitative sample amplitude and phase distributions avoiding aberration. However, it requires field of view (FoV) scanning often relying on mechanical translation, which not only slows down measuring speed, but also introduces mechanical errors decreasing both resolution and accuracy in retrieved information. In order to achieve high-accurate quantitative imaging with fast speed, digital micromirror device (DMD) is adopted in PIE for large FoV scanning controlled by on/off state coding by DMD. Measurements were implemented using biological samples as well as USAF resolution target, proving high resolution in quantitative imaging using the proposed system. Considering its fast and accurate imaging capability, it is believed the DMD based PIE technique provides a potential solution for medical observation and measurements.

  20. The Framework of Intervention Engine Based on Learning Analytics

    Science.gov (United States)

    Sahin, Muhittin; Yurdugül, Halil

    2017-01-01

    Learning analytics primarily deals with the optimization of learning environments and the ultimate goal of learning analytics is to improve learning and teaching efficiency. Studies on learning analytics seem to have been made in the form of adaptation engine and intervention engine. Adaptation engine studies are quite widespread, but intervention…

  1. Antimisting kerosene: Base fuel effects, blending and quality control techniques

    Science.gov (United States)

    Yavrouian, A. H.; Ernest, J.; Sarohia, V.

    1984-01-01

    The problems associated with blending of the AMK additive with Jet A, and the base fuel effects on AMK properties are addressed. The results from the evaluation of some of the quality control techniques for AMK are presented. The principal conclusions of this investigation are: significant compositional differences for base fuel (Jet A) within the ASTM specification DI655; higher aromatic content of the base fuel was found to be beneficial for the polymer dissolution at ambient (20 C) temperature; using static mixer technology, the antimisting additive (FM-9) is in-line blended with Jet A, producing AMK which has adequate fire-protection properties 15 to 20 minutes after blending; degradability of freshly blended and equilibrated AMK indicated that maximum degradability is reached after adequate fire protection is obtained; the results of AMK degradability as measured by filter ratio, confirmed previous RAE data that power requirements to decade freshly blended AMK are significantly higher than equilibrated AMK; blending of the additive by using FM-9 concentrate in Jet A produces equilibrated AMK almost instantly; nephelometry offers a simple continuous monitoring capability and is used as a real time quality control device for AMK; and trajectory (jet thurst) and pressure drop tests are useful laboratory techniques for evaluating AMK quality.

  2. Identification and measurement of combustion noise from a turbofan engine using correlation and coherence techniques. Ph.D. Thesis

    Science.gov (United States)

    Karchmer, A. M.

    1977-01-01

    Fluctuating pressure measurements within the combustor and tailpipe of a turbofan engine are made simultaneously with far field acoustic measurements. The pressure measurements within the engine are accomplished with cooled semi-infinite waveguide probes utilizing conventional condenser microphones as the transducers. The measurements are taken over a broad range of engine operating conditions and for 16 far field microphone positions between 10 deg and 160 deg relative to the engine inlet axis. Correlation and coherence techniques are used to determine the relative phase and amplitude relationships between the internal pressures and far field acoustic pressures. The results indicate that the combustor is a low frequency source region for acoustic propagation through the tailpipe and out to the far field. Specifically, it is found that the relation between source pressure and the resulting sound pressure involves a 180 deg phase shift. The latter result is obtained by Fourier transforming the cross correlation function between the source pressure and acoustic pressure after removing the propagation delay time. Further, it is found that the transfer function between the source pressure and acoustic pressure has a magnitude approximately proportional to frequency squared. These results are shown to be consistent with a model using a modified source term in Lighthill's turbulence stress tensor, wherein the fluctuating Reynolds stresses are replaced with the pressure fluctuations due to fluctuating entropy.

  3. Engineering Rugged Field Assays to Detect Hazardous Chemicals Using Spore-Based Bacterial Biosensors.

    Science.gov (United States)

    Wynn, Daniel; Deo, Sapna; Daunert, Sylvia

    2017-01-01

    Bacterial whole cell-based biosensors have been genetically engineered to achieve selective and reliable detection of a wide range of hazardous chemicals. Although whole-cell biosensors demonstrate many advantages for field-based detection of target analytes, there are still some challenges that need to be addressed. Most notably, their often modest shelf life and need for special handling and storage make them challenging to use in situations where access to reagents, instrumentation, and expertise are limited. These problems can be circumvented by developing biosensors in Bacillus spores, which can be engineered to address all of these concerns. In its sporulated state, a whole cell-based biosensor has a remarkably long life span and is exceptionally resistant to environmental insult. When these spores are germinated for use in analytical techniques, they show no loss in performance, even after long periods of storage under harsh conditions. In this chapter, we will discuss the development and use of whole cell-based sensors, their adaptation to spore-based biosensors, their current applications, and future directions in the field. © 2017 Elsevier Inc. All rights reserved.

  4. 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

  5. Full-duplex MIMO system based on antenna cancellation technique

    DEFF Research Database (Denmark)

    Foroozanfard, Ehsan; Franek, Ondrej; Tatomirescu, Alexandru

    2014-01-01

    The performance of an antenna cancellation technique for a multiple-input– multiple-output (MIMO) full-duplex system that is based on null-steering beamforming and antenna polarization diversity is investigated. A practical implementation of a symmetric antenna topology comprising three dual......-polarized patch antennas operating at 2.4 GHz is described. The measurement results show an average of 60 dB self-interference cancellation over 200 MHz bandwidth. Moreover, a decoupling level of up to 22 dB is achieved for MIMO multiplexing using antenna polarization diversity. The performance evaluation...

  6. Radiation-hard/high-speed array-based optical engine

    International Nuclear Information System (INIS)

    Gan, K.K.; Kagan, H.P.; Kass, R.D.; Moore, J.; Smith, D.S.; Buchholz, P.; Heidbrink, S.; Vogt, M.; Ziolkowski, M.

    2016-01-01

    We have designed and fabricated a compact array-based optical engine for transmitting data at 10 Gb/s. The device consists of a 4-channel ASIC driving a VCSEL (Vertical Cavity Surface Emitting Laser) array in an optical package. The ASIC is designed using only core transistors in a 65 nm CMOS process to enhance the radiation-hardness. The ASIC contains an 8-bit DAC to control the bias and modulation currents of the individual channels in the VCSEL array. The DAC settings are stored in SEU (single event upset) tolerant registers. Several devices were irradiated with 24 GeV/c protons and the performance of the devices is satisfactory after the irradiation.

  7. Repository-based software engineering program: Concept document

    Science.gov (United States)

    1992-01-01

    This document provides the context for Repository-Based Software Engineering's (RBSE's) evolving functional and operational product requirements, and it is the parent document for development of detailed technical and management plans. When furnished, requirements documents will serve as the governing RBSE product specification. The RBSE Program Management Plan will define resources, schedules, and technical and organizational approaches to fulfilling the goals and objectives of this concept. The purpose of this document is to provide a concise overview of RBSE, describe the rationale for the RBSE Program, and define a clear, common vision for RBSE team members and customers. The document also provides the foundation for developing RBSE user and system requirements and a corresponding Program Management Plan. The concept is used to express the program mission to RBSE users and managers and to provide an exhibit for community review.

  8. Optimization of Classical Hydraulic Engine Mounts Based on RMS Method

    Directory of Open Access Journals (Sweden)

    J. Christopherson

    2005-01-01

    Full Text Available Based on RMS averaging of the frequency response functions of the absolute acceleration and relative displacement transmissibility, optimal parameters describing the hydraulic engine mount are determined to explain the internal mount geometry. More specifically, it is shown that a line of minima exists to define a relationship between the absolute acceleration and relative displacement transmissibility of a sprung mass using a hydraulic mount as a means of suspension. This line of minima is used to determine several optimal systems developed on the basis of different clearance requirements, hence different relative displacement requirements, and compare them by means of their respective acceleration and displacement transmissibility functions. In addition, the transient response of the mount to a step input is also investigated to show the effects of the optimization upon the time domain response of the hydraulic mount.

  9. A review on powder-based additive manufacturing for tissue engineering: selective laser sintering and inkjet 3D printing

    Science.gov (United States)

    Farid Seyed Shirazi, Seyed; Gharehkhani, Samira; Mehrali, Mehdi; Yarmand, Hooman; Metselaar, Hendrik Simon Cornelis; Adib Kadri, Nahrizul; Azuan Abu Osman, Noor

    2015-06-01

    Since most starting materials for tissue engineering are in powder form, using powder-based additive manufacturing methods is attractive and practical. The principal point of employing additive manufacturing (AM) systems is to fabricate parts with arbitrary geometrical complexity with relatively minimal tooling cost and time. Selective laser sintering (SLS) and inkjet 3D printing (3DP) are two powerful and versatile AM techniques which are applicable to powder-based material systems. Hence, the latest state of knowledge available on the use of AM powder-based techniques in tissue engineering and their effect on mechanical and biological properties of fabricated tissues and scaffolds must be updated. Determining the effective setup of parameters, developing improved biocompatible/bioactive materials, and improving the mechanical/biological properties of laser sintered and 3D printed tissues are the three main concerns which have been investigated in this article.

  10. A review on powder-based additive manufacturing for tissue engineering: selective laser sintering and inkjet 3D printing.

    Science.gov (United States)

    Shirazi, Seyed Farid Seyed; Gharehkhani, Samira; Mehrali, Mehdi; Yarmand, Hooman; Metselaar, Hendrik Simon Cornelis; Adib Kadri, Nahrizul; Osman, Noor Azuan Abu

    2015-06-01

    Since most starting materials for tissue engineering are in powder form, using powder-based additive manufacturing methods is attractive and practical. The principal point of employing additive manufacturing (AM) systems is to fabricate parts with arbitrary geometrical complexity with relatively minimal tooling cost and time. Selective laser sintering (SLS) and inkjet 3D printing (3DP) are two powerful and versatile AM techniques which are applicable to powder-based material systems. Hence, the latest state of knowledge available on the use of AM powder-based techniques in tissue engineering and their effect on mechanical and biological properties of fabricated tissues and scaffolds must be updated. Determining the effective setup of parameters, developing improved biocompatible/bioactive materials, and improving the mechanical/biological properties of laser sintered and 3D printed tissues are the three main concerns which have been investigated in this article.

  11. Gendered practices of constructing an engineering identity in a problem-based learning environment

    DEFF Research Database (Denmark)

    Du, Xiangyun

    2006-01-01

    This article examines the learning experiences of engineering students of both genders in a problem-based and project-organized learning environment (PBL) at a Danish university. This study relates an amalgam of theories on learning and gender to the context of engineering education. Based on data...... from a qualitative study of an electrical and electronics engineering study programme, this study found that studying engineering in a PBL environment involves not only the mastery of technological knowledge but also an engineering identity development process. However, the association...... of an engineering identity with masculinity and the culturally defined engineering competencies leads to different learning experiences for male and female students. The nature of hard-core engineering subjects, based on male interests, privileges men and acts as a barrier to women. The masculine culture...

  12. Radiation-Based Medical Imaging Techniques: An Overview

    Science.gov (United States)

    Prior, John O.; Lecoq, Paul

    This chapter will present an overview of two radiation-based medical imaging techniques using radiopharmaceuticals used in nuclear medicine/molecular imaging, namely, single-photon emission computed tomography (SPECT) and positron emission tomography (PET). The relative merits in terms of radiation sensitivity and image resolution of SPECT and PET will be compared to the main conventional radiologic modalities that are computed tomography (CT) and magnetic resonance (MR) imaging. Differences in terms of temporal resolution will also be outlined, as well as the other similarities and dissimilarities of these two techniques, including their latest and upcoming multimodality combination. The main clinical applications are briefly described and examples of specific SPECT and PET radiopharmaceuticals are listed. SPECT and PET imaging will be then further detailed in the two subsequent chapters describing in greater depth the basics and future trends of each technique (see Chaps. 37, "SPECT Imaging: Basics and New Trends" 10.1007/978-3-642-13271-1_37 and 38, "PET Imaging: Basics and New Trends" 10.1007/978-3-642-13271-1_38.

  13. Nitrous oxide-based techniques versus nitrous oxide-free techniques for general anaesthesia.

    Science.gov (United States)

    Sun, Rao; Jia, Wen Qin; Zhang, Peng; Yang, KeHu; Tian, Jin Hui; Ma, Bin; Liu, Yali; Jia, Run H; Luo, Xiao F; Kuriyama, Akira

    2015-11-06

    Nitrous oxide has been used for over 160 years for the induction and maintenance of general anaesthesia. It has been used as a sole agent but is most often employed as part of a technique using other anaesthetic gases, intravenous agents, or both. Its low tissue solubility (and therefore rapid kinetics), low cost, and low rate of cardiorespiratory complications have made nitrous oxide by far the most commonly used general anaesthetic. The accumulating evidence regarding adverse effects of nitrous oxide administration has led many anaesthetists to question its continued routine use in a variety of operating room settings. Adverse events may result from both the biological actions of nitrous oxide and the fact that to deliver an effective dose, nitrous oxide, which is a relatively weak anaesthetic agent, needs to be given in high concentrations that restrict oxygen delivery (for example, a common mixture is 30% oxygen with 70% nitrous oxide). As well as the risk of low blood oxygen levels, concerns have also been raised regarding the risk of compromising the immune system, impaired cognition, postoperative cardiovascular complications, bowel obstruction from distention, and possible respiratory compromise. To determine if nitrous oxide-based anaesthesia results in similar outcomes to nitrous oxide-free anaesthesia in adults undergoing surgery. We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2014 Issue 10); MEDLINE (1966 to 17 October 2014); EMBASE (1974 to 17 October 2014); and ISI Web of Science (1974 to 17 October 2014). We also searched the reference lists of relevant articles, conference proceedings, and ongoing trials up to 17 October 2014 on specific websites (http://clinicaltrials.gov/, http://controlled-trials.com/, and http://www.centerwatch.com). We included randomized controlled trials (RCTs) comparing general anaesthesia where nitrous oxide was part of the anaesthetic technique used for the induction or maintenance of general

  14. Cellular uptake and intracellular fate of engineered nanoparticles: a review on the application of imaging techniques.

    Science.gov (United States)

    Tantra, Ratna; Knight, Alex

    2011-09-01

    The use of imaging tools to probe nanoparticle-cell interactions will be crucial to elucidating the mechanisms of nanoparticle-induced toxicity. Of particular interest are mechanisms associated with cell penetration, translocation and subsequent accumulation inside the cell, or in cellular compartments. The objective of the present paper is to review imaging techniques that have been previously used in order to assess such interactions, and new techniques with the potential to be useful in this area. In order to identify the most suitable techniques, they were evaluated and matched against a list of evaluation criteria. We conclude that limitations exist with all of the techniques and the ultimate choice will thus depend on the needs of end users, and their particular application. The state-of-the-art techniques appear to have the least limitations, despite the fact that they are not so well established and still far from being routine. For example, super-resolution microscopy techniques appear to have many advantages for understanding the details of the interactions between nanoparticles and cells. Future research should concentrate on further developing or improving such novel techniques, to include the development of standardized methods and appropriate reference materials.

  15. Structural level characterization of base oils using advanced analytical techniques

    KAUST Repository

    Hourani, Nadim

    2015-05-21

    Base oils, blended for finished lubricant formulations, are classified by the American Petroleum Institute into five groups, viz., groups I-V. Groups I-III consist of petroleum based hydrocarbons whereas groups IV and V are made of synthetic polymers. In the present study, five base oil samples belonging to groups I and III were extensively characterized using high performance liquid chromatography (HPLC), comprehensive two-dimensional gas chromatography (GC×GC), and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) equipped with atmospheric pressure chemical ionization (APCI) and atmospheric pressure photoionization (APPI) sources. First, the capabilities and limitations of each analytical technique were evaluated, and then the availed information was combined to reveal compositional details on the base oil samples studied. HPLC showed the overwhelming presence of saturated over aromatic compounds in all five base oils. A similar trend was further corroborated using GC×GC, which yielded semiquantitative information on the compound classes present in the samples and provided further details on the carbon number distributions within these classes. In addition to chromatography methods, FT-ICR MS supplemented the compositional information on the base oil samples by resolving the aromatics compounds into alkyl- and naphtheno-subtituted families. APCI proved more effective for the ionization of the highly saturated base oil components compared to APPI. Furthermore, for the detailed information on hydrocarbon molecules FT-ICR MS revealed the presence of saturated and aromatic sulfur species in all base oil samples. The results presented herein offer a unique perspective into the detailed molecular structure of base oils typically used to formulate lubricants. © 2015 American Chemical Society.

  16. Determination of the ecological connectivity between landscape patches obtained using the knowledge engineer (expert) classification technique

    Science.gov (United States)

    Selim, Serdar; Sonmez, Namik Kemal; Onur, Isin; Coslu, Mesut

    2017-10-01

    Connection of similar landscape patches with ecological corridors supports habitat quality of these patches, increases urban ecological quality, and constitutes an important living and expansion area for wild life. Furthermore, habitat connectivity provided by urban green areas is supporting biodiversity in urban areas. In this study, possible ecological connections between landscape patches, which were achieved by using Expert classification technique and modeled with probabilistic connection index. Firstly, the reflection responses of plants to various bands are used as data in hypotheses. One of the important features of this method is being able to use more than one image at the same time in the formation of the hypothesis. For this reason, before starting the application of the Expert classification, the base images are prepared. In addition to the main image, the hypothesis conditions were also created for each class with the NDVI image which is commonly used in the vegetation researches. Besides, the results of the previously conducted supervised classification were taken into account. We applied this classification method by using the raster imagery with user-defined variables. Hereupon, to provide ecological connections of the tree cover which was achieved from the classification, we used Probabilistic Connection (PC) index. The probabilistic connection model which is used for landscape planning and conservation studies via detecting and prioritization critical areas for ecological connection characterizes the possibility of direct connection between habitats. As a result we obtained over % 90 total accuracy in accuracy assessment analysis. We provided ecological connections with PC index and we created inter-connected green spaces system. Thus, we offered and implicated green infrastructure system model takes place in the agenda of recent years.

  17. Using the Engineering Design Cycle to Develop Integrated Project Based Learning in Aerospace Engineering

    NARCIS (Netherlands)

    Saunders-Smits, G.N.; Roling, P.; Brügemann, V.; Timmer, N.; Melkert, J.

    2012-01-01

    Over the past four years the Faculty of Aerospace Engineering at Delft University of Technology in the Netherlands has redeveloped its BSc curriculum to mimic an engineering design cycle. Each semester represents a step in the design cycle: exploration; system design; sub-system design; test,

  18. Genetic engineering technology for the improvement of the sterile insect technique. Proceedings of a final research co-ordination meeting

    International Nuclear Information System (INIS)

    1998-01-01

    Since the beginning of the joint FAO/IAEA programme on the research and development of insect pest control methodology, emphasis has been placed on the basic and applied aspects of implementing the sterile insect technique (SIT). Special emphasis has always been directed at the assembly of technological progress into workable systems that can be implemented in developing countries. The general intention is to solve problems associated with insect pests that have an adverse impact on production of food and fibre. For several insect species SIT has proven to be a powerful method for control. This includes the New World screwworm fly (Cochliomyia hominivorox), the Mediterranean fruit fly (Ceratitis capitata), the melon fly (Bactrocera cucurbitae), the Queensland fruit fly (Bactrocera tryoni) and one tsetse fly species (Glossina austeni). Improvements of the SIT are possible, especially through the use of molecular techniques. The final report of the Co-ordinated Research Programme on ''Genetic Engineering Technology for the Improvement of the Sterile Insect Technique'' highlights the progress made towards the development of transformation systems for non-drosophilid insects and the research aimed at the identification and engineering of potential target genes or traits

  19. Production technique of vermicular graphite iron cylinder head of vehicle diesel engine

    OpenAIRE

    Zhou Gen; Liu Wanhua

    2008-01-01

    The 25 years’production and application have proved that vermicular graphite iron cylinder heads with vermicularity ≥50% satisfy the machinability and performance demand of diesel engine. The method, in which using cupola-induction furnace duplex melting and pour-over process with rare earth-ferrosilicon or rare earthsilicon compound as vermicularizing alloy plus rare earth-magnesium-ferrosilicon as stirring alloy, is an optimal vermicularizing process for obtaining satisfi ed vermicularity. ...

  20. Re-engineering forensic anthropology : new techniques in sharp force trauma analysis

    OpenAIRE

    Norman, D. G.; Burnett, B.; Gibbons, G. J.; Barnes-Warden, J.; Williams, M. A.

    2012-01-01

    In forensic anthropology the analysis of microscopic tool marks found in skeletal sharp force trauma is a challenging area. Many different imaging methods have been employed to measure cut mark characteristics in aid of developing diagnostic tools for estimating knife type used for these marks. Furthermore numerous experimental methods for creating tool marks for analysis have been used. A novel method for creating, analysing and presenting tool marks using reverse engineering and metrology w...

  1. Microporous membrane-based liver tissue engineering for the reconstruction of three-dimensional functional liver tissues in vitro.

    Science.gov (United States)

    Kasuya, Junichi; Tanishita, Kazuo

    2012-01-01

    To meet the increasing demand for liver tissue engineering, various three-dimensional (3D) liver cell culture techniques have been developed. Nevertheless, conventional liver cell culture techniques involving the suspending cells in extracellular matrix (ECM) components and the seeding of cells into 3D biodegradable scaffolds have an intrinsic shortcoming, low cell-scaffold ratios. We have developed a microporous membrane-based liver cell culture technique. Cell behaviors and tissue organization can be controlled by membrane geometry, and cell-dense thick tissues can be reconstructed by layering cells cultured on biodegradable microporous membranes. Applications extend from liver parenchymal cell monoculture to multi-cell type cultures for the reconstruction of 3D functional liver tissue. This review focuses on the expanding role for microporous membranes in liver tissue engineering, primarily from our research.

  2. On HTML and XML based web design and implementation techniques

    International Nuclear Information System (INIS)

    Bezboruah, B.; Kalita, M.

    2006-05-01

    Web implementation is truly a multidisciplinary field with influences from programming, choosing of scripting languages, graphic design, user interface design, and database design. The challenge of a Web designer/implementer is his ability to create an attractive and informative Web. To work with the universal framework and link diagrams from the design process as well as the Web specifications and domain information, it is essential to create Hypertext Markup Language (HTML) or other software and multimedia to accomplish the Web's objective. In this article we will discuss Web design standards and the techniques involved in Web implementation based on HTML and Extensible Markup Language (XML). We will also discuss the advantages and disadvantages of HTML over its successor XML in designing and implementing a Web. We have developed two Web pages, one utilizing the features of HTML and the other based on the features of XML to carry out the present investigation. (author)

  3. Thiophene-based monolayer OFETs prepared by Langmuir techniques

    Science.gov (United States)

    Agina, Elena V.; Sizov, Alexey S.; Anisimov, Daniil S.; Trul, Askold A.; Borshchev, Oleg V.; Paraschuk, Dmitry Y.; Shcherbina, Maxim A.; Chvalun, Sergey N.; Ponomarenko, Sergey A.

    2015-08-01

    A novel fast, easily processible and highly reproducible approach to thiophene-based monolayer OFETs fabrication by Langmuir-Blodgett or Langmuir-Schaefer techniques was developed and successfully applied. It is based on selfassembly of organosilicon derivatives of oligothiophenes or benzothienobenzothiophene on the water-air interface. Influence of the conjugation length and the anchor group chemistry of the self-assembling molecules on the monolayer structure and electric performance of monolayer OFETs was systematically investigated. The efficient monolayer OFETs with the charge carrier mobilities up to 0.01 cm2/Vs and on/off ratio up to 106 were fabricated, and their functionality in integrated circuits under normal air conditions was demonstrated.

  4. Designing on ICT reconstruction software based on DSP techniques

    International Nuclear Information System (INIS)

    Liu Jinhui; Xiang Xincheng

    2006-01-01

    The convolution back project (CBP) algorithm is used to realize the CT image's reconstruction in ICT generally, which is finished by using PC or workstation. In order to add the ability of multi-platform operation of CT reconstruction software, a CT reconstruction method based on modern digital signal processor (DSP) technique is proposed and realized in this paper. The hardware system based on TI's C6701 DSP processor is selected to support the CT software construction. The CT reconstruction software is compiled only using assembly language related to the DSP hardware. The CT software can be run on TI's C6701 EVM board by inputting the CT data, and can get the CT Images that satisfy the real demands. (authors)

  5. FY71 Engineering Report on Surveillance Techniques for Civil Aviation Security

    Science.gov (United States)

    1971-11-01

    This document discusses the work performed by the TSC task group on surveillance techniques in FY71. The principal section is devoted to the technical description, classification and evaluation of commercial metal detectors for concealed weapons. It ...

  6. Glass-based integrated optical splitters: engineering oriented research

    Science.gov (United States)

    Hao, Yinlei; Zheng, Weiwei; Yang, Jianyi; Jiang, Xiaoqing; Wang, Minghua

    2010-10-01

    Optical splitter is one of most typical device heavily demanded in implementation of Fiber To The Home (FTTH) system. Due to its compatibility with optical fibers, low propagation loss, flexibility, and most distinguishingly, potentially costeffectiveness, glass-based integrated optical splitters made by ion-exchange technology promise to be very attractive in application of optical communication networks. Aiming at integrated optical splitters applied in optical communication network, glass ion-exchange waveguide process is developed, which includes two steps: thermal salts ion-exchange and field-assisted ion-diffusion. By this process, high performance optical splitters are fabricated in specially melted glass substrate. Main performance parameters of these splitters, including maximum insertion loss (IL), polarization dependence loss (PDL), and IL uniformity are all in accordance with corresponding specifications in generic requirements for optic branching components (GR-1209-CORE). In this paper, glass based integrated optical splitters manufacturing is demonstrated, after which, engineering-oriented research work results on glass-based optical splitter are presented.

  7. Evidence-based Medicine Search: a customizable federated search engine.

    Science.gov (United States)

    Bracke, Paul J; Howse, David K; Keim, Samuel M

    2008-04-01

    This paper reports on the development of a tool by the Arizona Health Sciences Library (AHSL) for searching clinical evidence that can be customized for different user groups. The AHSL provides services to the University of Arizona's (UA's) health sciences programs and to the University Medical Center. Librarians at AHSL collaborated with UA College of Medicine faculty to create an innovative search engine, Evidence-based Medicine (EBM) Search, that provides users with a simple search interface to EBM resources and presents results organized according to an evidence pyramid. EBM Search was developed with a web-based configuration component that allows the tool to be customized for different specialties. Informal and anecdotal feedback from physicians indicates that EBM Search is a useful tool with potential in teaching evidence-based decision making. While formal evaluation is still being planned, a tool such as EBM Search, which can be configured for specific user populations, may help lower barriers to information resources in an academic health sciences center.

  8. Engineering nanomaterials-based biosensors for food safety detection.

    Science.gov (United States)

    Lv, Man; Liu, Yang; Geng, Jinhui; Kou, Xiaohong; Xin, Zhihong; Yang, Dayong

    2018-05-30

    Food safety always remains a grand global challenge to human health, especially in developing countries. To solve food safety pertained problems, numerous strategies have been developed to detect biological and chemical contaminants in food. Among these approaches, nanomaterials-based biosensors provide opportunity to realize rapid, sensitive, efficient and portable detection, overcoming the restrictions and limitations of traditional methods such as complicated sample pretreatment, long detection time, and relying on expensive instruments and well-trained personnel. In this review article, we provide a cross-disciplinary perspective to review the progress of nanomaterials-based biosensors for the detection of food contaminants. The review article is organized by the category of food contaminants including pathogens/toxins, heavy metals, pesticides, veterinary drugs and illegal additives. In each category of food contaminant, the biosensing strategies are summarized including optical, colorimetric, fluorescent, electrochemical, and immune- biosensors; the relevant analytes, nanomaterials and biosensors are analyzed comprehensively. Future perspectives and challenges are also discussed briefly. We envision that our review could bridge the gap between the fields of food science and nanotechnology, providing implications for the scientists or engineers in both areas to collaborate and promote the development of nanomaterials-based biosensors for food safety detection. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Risk-based maintenance-Techniques and applications

    International Nuclear Information System (INIS)

    Arunraj, N.S.; Maiti, J.

    2007-01-01

    Plant and equipment, however well designed, will not remain safe or reliable if it is not maintained. The general objective of the maintenance process is to make use of the knowledge of failures and accidents to achieve the possible safety with the lowest possible cost. The concept of risk-based maintenance was developed to inspect the high-risk components usually with greater frequency and thoroughness and to maintain in a greater manner, to achieve tolerable risk criteria. Risk-based maintenance methodology provides a tool for maintenance planning and decision making to reduce the probability of failure of equipment and the consequences of failure. In this paper, the risk analysis and risk-based maintenance methodologies were identified and classified into suitable classes. The factors affecting the quality of risk analysis were identified and analyzed. The applications, input data and output data were studied to understand their functioning and efficiency. The review showed that there is no unique way to perform risk analysis and risk-based maintenance. The use of suitable techniques and methodologies, careful investigation during the risk analysis phase, and its detailed and structured results are necessary to make proper risk-based maintenance decisions

  10. Generation of Quasi-Gaussian Pulses Based on Correlation Techniques

    Directory of Open Access Journals (Sweden)

    POHOATA, S.

    2012-02-01

    Full Text Available The Gaussian pulses have been mostly used within communications, where some applications can be emphasized: mobile telephony (GSM, where GMSK signals are used, as well as the UWB communications, where short-period pulses based on Gaussian waveform are generated. Since the Gaussian function signifies a theoretical concept, which cannot be accomplished from the physical point of view, this should be expressed by using various functions, able to determine physical implementations. New techniques of generating the Gaussian pulse responses of good precision are approached, proposed and researched in this paper. The second and third order derivatives with regard to the Gaussian pulse response are accurately generated. The third order derivates is composed of four individual rectangular pulses of fixed amplitudes, being easily to be generated by standard techniques. In order to generate pulses able to satisfy the spectral mask requirements, an adequate filter is necessary to be applied. This paper emphasizes a comparative analysis based on the relative error and the energy spectra of the proposed pulses.

  11. Semantic-based technique for thai documents plagiarism detection

    Directory of Open Access Journals (Sweden)

    Sorawat Prapanitisatian

    2014-03-01

    Full Text Available Plagiarism is the act of taking another person's writing or idea without referring to the source of information. This is one of major problems in educational institutes. There is a number of plagiarism detection software available on the Internet. However, a few numbers of them works. Typically, they use a simple method for plagiarism detection e.g. string matching. The main weakness of this method is it cannot detect the plagiarism when the author replaces some words using synonyms. As such, this paper presents a new technique for a semantic-based plagiarism detection using Semantic Role Labeling (SRL and term weighting. SRL is deployed in order to calculate the semantic-based similarity. The main different from the existing framework is terms in a sentence are weighted dynamically depending on their roles in the sentence e.g. subject, verb or object. This technique enhances the plagiarism detection mechanism more efficiently than existing system although positions of terms in a sentence are reordered. The experimental results show that the proposed method can detect the plagiarism document more effective than the existing methods, Anti-kobpae, Turnit-in and Traditional Semantic Role Labeling.

  12. Reuse fo a Cold War Surveillance Drone to Flight Test a NASA Rocket Based Combined Cycle Engine

    Science.gov (United States)

    Brown, T. M.; Smith, Norm

    1999-01-01

    Plans for and early feasibility investigations into the modification of a Lockheed D21B drone to flight test the DRACO Rocket Based Combined Cycle (RBCC) engine are discussed. Modifications include the addition of oxidizer tanks, modern avionics systems, actuators, and a vehicle recovery system. Current study results indicate that the D21B is a suitable candidate for this application and will allow demonstrations of all DRACO engine operating modes at Mach numbers between 0.8 and 4.0. Higher Mach numbers may be achieved with more extensive modification. Possible project risks include low speed stability and control, and recovery techniques.

  13. Applying systems engineering to implement an evidence-based intervention at a community health center.

    Science.gov (United States)

    Tu, Shin-Ping; Feng, Sherry; Storch, Richard; Yip, Mei-Po; Sohng, HeeYon; Fu, Mingang; Chun, Alan

    2012-11-01

    Impressive results in patient care and cost reduction have increased the demand for systems-engineering methodologies in large health care systems. This Report from the Field describes the feasibility of applying systems-engineering techniques at a community health center currently lacking the dedicated expertise and resources to perform these activities.

  14. Chemically engineered graphene-based 2D organic molecular magnet.

    Science.gov (United States)

    Hong, Jeongmin; Bekyarova, Elena; de Heer, Walt A; Haddon, Robert C; Khizroev, Sakhrat

    2013-11-26

    Carbon-based magnetic materials and structures of mesoscopic dimensions may offer unique opportunities for future nanomagnetoelectronic/spintronic devices. To achieve their potential, carbon nanosystems must have controllable magnetic properties. We demonstrate that nitrophenyl functionalized graphene can act as a room-temperature 2D magnet. We report a comprehensive study of low-temperature magnetotransport, vibrating sample magnetometry (VSM), and superconducting quantum interference (SQUID) measurements before and after radical functionalization. Following nitrophenyl (NP) functionalization, epitaxially grown graphene systems can become organic molecular magnets with ferromagnetic and antiferromagnetic ordering that persists at temperatures above 400 K. The field-dependent, surface magnetoelectric properties were studied using scanning probe microscopy (SPM) techniques. The results indicate that the NP-functionalization orientation and degree of coverage directly affect the magnetic properties of the graphene surface. In addition, graphene-based organic magnetic nanostructures were found to demonstrate a pronounced magneto-optical Kerr effect (MOKE). The results were consistent across different characterization techniques and indicate room-temperature magnetic ordering along preferred graphene orientations in the NP-functionalized samples. Chemically isolated graphene nanoribbons (CINs) were observed along the preferred functionality directions. These results pave the way for future magnetoelectronic/spintronic applications based on promising concepts such as current-induced magnetization switching, magnetoelectricity, half-metallicity, and quantum tunneling of magnetization.

  15. A Case Study: Problem-Based Learning for Civil Engineering Students in Transportation Courses

    Science.gov (United States)

    Ahern, A. A.

    2010-01-01

    This paper describes two case studies where problem-based learning (PBL) has been introduced to undergraduate civil engineering students in University College Dublin. PBL has recently been put in place in the penultimate and final year transport engineering classes in the civil engineering degree in University College Dublin. In this case study,…

  16. Zephyr: A secure Internet-based process to streamline engineering procurements using the World Wide Web

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, C.W.; Cavitt, R.E.; Niven, W.A.; Warren, F.E.; Taylor, S.S.; Sharick, T.M.; Vickers, D.L.; Mitschkowetz, N.; Weaver, R.L.

    1996-08-13

    Lawrence Livermore National Laboratory (LLNL) is piloting an Internet- based paperless process called `Zephyr` to streamline engineering procurements. Major benefits have accrued by using Zephyr in reducing procurement time, speeding the engineering development cycle, facilitating industrial collaboration, and reducing overall costs. Programs at LLNL are benefiting by the efficiencies introduced since implementing Zephyr`s engineering and commerce on the Internet.

  17. RFID-Based Multidisciplinary Educational Platform to Improve the Engineering and Technology Curriculums

    Science.gov (United States)

    Yelamarthi, Kumar

    2012-01-01

    Multidisciplinary projects involving electrical engineering (EE), mechanical engineering (ME), and computer engineering (CE) students are both exciting and difficult to conceptualize. Answering this challenge, this paper presents a multidisciplinary educational platform on radio frequency identification-based assistive devices. The combination of…

  18. The Suitability of Cloud-Based Speech Recognition Engines for Language Learning

    Science.gov (United States)

    Daniels, Paul; Iwago, Koji

    2017-01-01

    As online automatic speech recognition (ASR) engines become more accurate and more widely implemented with call software, it becomes important to evaluate the effectiveness and the accuracy of these recognition engines using authentic speech samples. This study investigates two of the most prominent cloud-based speech recognition engines--Apple's…

  19. Refractive index sensor based on optical fiber end face using pulse reference-based compensation technique

    Science.gov (United States)

    Bian, Qiang; Song, Zhangqi; Zhang, Xueliang; Yu, Yang; Chen, Yuzhong

    2018-03-01

    We proposed a refractive index sensor based on optical fiber end face using pulse reference-based compensation technique. With good compensation effect of this compensation technique, the power fluctuation of light source, the change of optic components transmission loss and coupler splitting ratio can be compensated, which largely reduces the background noise. The refractive index resolutions can achieve 3.8 × 10-6 RIU and1.6 × 10-6 RIU in different refractive index regions.

  20. Enhancing the effectiveness of IST through risk-based techniques

    Energy Technology Data Exchange (ETDEWEB)

    Floyd, S.D.

    1996-12-01

    Current IST requirements were developed mainly through deterministic-based methods. While this approach has resulted in an adequate level of safety and reliability for pumps and valves, insights from probabilistic safety assessments suggest a better safety focus can be achieved at lower costs. That is, some high safety impact pumps and valves are currently not tested under the IST program and should be added, while low safety impact valves could be tested at significantly greater intervals than allowed by the current IST program. The nuclear utility industry, through the Nuclear Energy Institute (NEI), has developed a draft guideline for applying risk-based techniques to focus testing on those pumps and valves with a high safety impact while reducing test frequencies on low safety impact pumps and valves. The guideline is being validated through an industry pilot application program that is being reviewed by the U.S. Nuclear Regulatory Commission. NEI and the ASME maintain a dialogue on the two groups` activities related to risk-based IST. The presenter will provide an overview of the NEI guideline, discuss the methodological approach for applying risk-based technology to IST and provide the status of the industry pilot plant effort.

  1. 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

  2. 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...

  3. 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...

  4. Shape-engineering substrate-based plasmonic nanomaterials

    Science.gov (United States)

    Gilroy, Kyle D.

    The advancement of next generation technologies is reliant on our ability to engineer matter at the nanoscale. Since the morphological features of nanomaterials dictate their chemical and physical properties, a significant effort has been put forth to develop syntheses aimed at fine tuning their size, shape and composition. This massive effort has resulted in a maturing colloidal chemistry containing an extensive collection of morphologies with compositions nearly spanning the entire transition of the periodic table. While colloidal nanoparticles have opened the door to promising applications in fields such as cancer theranostics, drug delivery, catalysis and sensing; the synthetic protocols for the placement of nanomaterials on surfaces, a requisite for chip-based devices, are ill-developed. This dissertation serves to address this limitation by highlighting a series of syntheses related to the design of substrate-based nanoparticles whose size, shape and composition are controllably engineered to a desired endpoint. The experimental methods are based on a template-mediated approach which sees chemical modifications made to prepositioned thermally assembled metal nanostructures which are well bonded to a sapphire substrate. The first series of investigations will highlight synthetic routes utilizing galvanic replacement reactions, where the prepositioned templates are chemically transformed into hollow nanoshells. Detailed studies are provided highlighting discoveries related to (i) hollowing, (ii) defect transfer, (iii) strain induction, (iv) interdiffusion, (v) crystal structure and (vi) the localized surface plasmon resonance (LSPR). The second series of investigations, based on heterogeneous nucleation, have Au templates serve as nucleation sites for metal atoms arriving in either the solution- or vapor phase. The solution-phase heterogeneous nucleation of Ag on Au reveals that chemical kinetics (injection rate & precursor concentration) can be used to control

  5. Production technique of vermicular graphite iron cylinder head of vehicle diesel engine

    Directory of Open Access Journals (Sweden)

    Zhou Gen

    2008-11-01

    Full Text Available The 25 years’production and application have proved that vermicular graphite iron cylinder heads with vermicularity ≥50% satisfy the machinability and performance demand of diesel engine. The method, in which using cupola-induction furnace duplex melting and pour-over process with rare earth-ferrosilicon or rare earthsilicon compound as vermicularizing alloy plus rare earth-magnesium-ferrosilicon as stirring alloy, is an optimal vermicularizing process for obtaining satisfi ed vermicularity. Using top kiss risers, enlarging kissing areas and expanding covering width and making ingates to freeze earlier are the effective measures to eliminate shrinkage, blowhole and oxide inclusions in the vermicular graphite iron cylinder heads.

  6. Towards characterising design-based learning in engineering education: a review of the literature

    Science.gov (United States)

    Gómez Puente, S. M.; van Eijck, M.; Jochems, W.

    2011-05-01

    Design-based learning is a teaching approach akin to problem-based learning but one to which the design of artefacts, systems and solutions in project-based settings is central. Although design-based learning has been employed in the practice of higher engineering education, it has hardly been theorised at this educational level. The aim of this study is to characterise design-based learning from existing empirical research literature on engineering education. Drawing on a perspective that accounts for domain-specific, idiosyncratic and learner-centred aspects of design problems in the context of engineering education, 50 empirical studies on project-based and problem-based engineering education, to which the design of artefacts is central, were reviewed. Based on the findings, design-based learning is characterised with regard to domain-specificity, learner expertise and task authenticity. The implications of this study for the practice of engineering education are discussed.

  7. Adjusting the specificity of an engine map based on the sensitivity of an engine control parameter relative to a performance variable

    Science.gov (United States)

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

    2014-10-28

    Methods and systems for engine control optimization are provided. A first and a second operating condition of a vehicle engine are detected. An initial value is identified for a first and a second engine control parameter corresponding to a combination of the detected operating conditions according to a first and a second engine map look-up table. The initial values for the engine control parameters are adjusted based on a detected engine performance variable to cause the engine performance variable to approach a target value. A first and a second sensitivity of the engine performance variable are determined in response to changes in the engine control parameters. The first engine map look-up table is adjusted when the first sensitivity is greater than a threshold, and the second engine map look-up table is adjusted when the second sensitivity is greater than a threshold.

  8. New Techniques for Deep Learning with Geospatial Data using TensorFlow, Earth Engine, and Google Cloud Platform

    Science.gov (United States)

    Hancher, M.

    2017-12-01

    Recent years have seen promising results from many research teams applying deep learning techniques to geospatial data processing. In that same timeframe, TensorFlow has emerged as the most popular framework for deep learning in general, and Google has assembled petabytes of Earth observation data from a wide variety of sources and made them available in analysis-ready form in the cloud through Google Earth Engine. Nevertheless, developing and applying deep learning to geospatial data at scale has been somewhat cumbersome to date. We present a new set of tools and techniques that simplify this process. Our approach combines the strengths of several underlying tools: TensorFlow for its expressive deep learning framework; Earth Engine for data management, preprocessing, postprocessing, and visualization; and other tools in Google Cloud Platform to train TensorFlow models at scale, perform additional custom parallel data processing, and drive the entire process from a single familiar Python development environment. These tools can be used to easily apply standard deep neural networks, convolutional neural networks, and other custom model architectures to a variety of geospatial data structures. We discuss our experiences applying these and related tools to a range of machine learning problems, including classic problems like cloud detection, building detection, land cover classification, as well as more novel problems like illegal fishing detection. Our improved tools will make it easier for geospatial data scientists to apply modern deep learning techniques to their own problems, and will also make it easier for machine learning researchers to advance the state of the art of those techniques.

  9. Chemistry research and chemical techniques based on research reactors

    International Nuclear Information System (INIS)

    1963-01-01

    Chemistry has occupied an important position historically in the sciences associated with nuclear reactors and it continues to play a prominent role in reactor-based research investigations. This Panel of prominent scientists in the field was convened by the International Atomic Energy Agency (IAEA) to assess the present state of such chemistry research for the information of its Member States and others interested in the subject. There are two ways in which chemistry is associated with nuclear reactors: (a) general applications to many scientific fields in which chemical techniques are involved as essential service functions; and (b) specific applications of reactor facilities to the solution of chemical problems themselves. Twenty years of basic research with nuclear reactors have demonstrated a very widespread, and still increasing, demand for radioisotopes and isotopically-labelled molecules in all fields of the physical and biological sciences. Similarly, the determination of the elemental composition of a material through the analytical technique of activation analysis can be applied throughout experimental science. Refs, figs and tabs

  10. Model-checking techniques based on cumulative residuals.

    Science.gov (United States)

    Lin, D Y; Wei, L J; Ying, Z

    2002-03-01

    Residuals have long been used for graphical and numerical examinations of the adequacy of regression models. Conventional residual analysis based on the plots of raw residuals or their smoothed curves is highly subjective, whereas most numerical goodness-of-fit tests provide little information about the nature of model misspecification. In this paper, we develop objective and informative model-checking techniques by taking the cumulative sums of residuals over certain coordinates (e.g., covariates or fitted values) or by considering some related aggregates of residuals, such as moving sums and moving averages. For a variety of statistical models and data structures, including generalized linear models with independent or dependent observations, the distributions of these stochastic processes tinder the assumed model can be approximated by the distributions of certain zero-mean Gaussian processes whose realizations can be easily generated by computer simulation. Each observed process can then be compared, both graphically and numerically, with a number of realizations from the Gaussian process. Such comparisons enable one to assess objectively whether a trend seen in a residual plot reflects model misspecification or natural variation. The proposed techniques are particularly useful in checking the functional form of a covariate and the link function. Illustrations with several medical studies are provided.

  11. Detecting Molecular Properties by Various Laser-Based Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Hsin, Tse-Ming [Iowa State Univ., Ames, IA (United States)

    2007-01-01

    Four different laser-based techniques were applied to study physical and chemical characteristics of biomolecules and dye molecules. These techniques are liole burning spectroscopy, single molecule spectroscopy, time-resolved coherent anti-Stokes Raman spectroscopy and laser-induced fluorescence microscopy. Results from hole burning and single molecule spectroscopy suggested that two antenna states (C708 & C714) of photosystem I from cyanobacterium Synechocystis PCC 6803 are connected by effective energy transfer and the corresponding energy transfer time is ~6 ps. In addition, results from hole burning spectroscopy indicated that the chlorophyll dimer of the C714 state has a large distribution of the dimer geometry. Direct observation of vibrational peaks and evolution of coumarin 153 in the electronic excited state was demonstrated by using the fs/ps CARS, a variation of time-resolved coherent anti-Stokes Raman spectroscopy. In three different solvents, methanol, acetonitrile, and butanol, a vibration peak related to the stretch of the carbonyl group exhibits different relaxation dynamics. Laser-induced fluorescence microscopy, along with the biomimetic containers-liposomes, allows the measurement of the enzymatic activity of individual alkaline phosphatase from bovine intestinal mucosa without potential interferences from glass surfaces. The result showed a wide distribution of the enzyme reactivity. Protein structural variation is one of the major reasons that are responsible for this highly heterogeneous behavior.

  12. A human visual based binarization technique for histological images

    Science.gov (United States)

    Shreyas, Kamath K. M.; Rajendran, Rahul; Panetta, Karen; Agaian, Sos

    2017-05-01

    In the field of vision-based systems for object detection and classification, thresholding is a key pre-processing step. Thresholding is a well-known technique for image segmentation. Segmentation of medical images, such as Computed Axial Tomography (CAT), Magnetic Resonance Imaging (MRI), X-Ray, Phase Contrast Microscopy, and Histological images, present problems like high variability in terms of the human anatomy and variation in modalities. Recent advances made in computer-aided diagnosis of histological images help facilitate detection and classification of diseases. Since most pathology diagnosis depends on the expertise and ability of the pathologist, there is clearly a need for an automated assessment system. Histological images are stained to a specific color to differentiate each component in the tissue. Segmentation and analysis of such images is problematic, as they present high variability in terms of color and cell clusters. This paper presents an adaptive thresholding technique that aims at segmenting cell structures from Haematoxylin and Eosin stained images. The thresholded result can further be used by pathologists to perform effective diagnosis. The effectiveness of the proposed method is analyzed by visually comparing the results to the state of art thresholding methods such as Otsu, Niblack, Sauvola, Bernsen, and Wolf. Computer simulations demonstrate the efficiency of the proposed method in segmenting critical information.

  13. Engineering of microorganisms for the production of biofuels and perspectives based on systems metabolic engineering approaches.

    Science.gov (United States)

    Jang, Yu-Sin; Park, Jong Myoung; Choi, Sol; Choi, Yong Jun; Seung, Do Young; Cho, Jung Hee; Lee, Sang Yup

    2012-01-01

    The increasing oil price and environmental concerns caused by the use of fossil fuel have renewed our interest in utilizing biomass as a sustainable resource for the production of biofuel. It is however essential to develop high performance microbes that are capable of producing biofuels with very high efficiency in order to compete with the fossil fuel. Recently, the strategies for developing microbial strains by systems metabolic engineering, which can be considered as metabolic engineering integrated with systems biology and synthetic biology, have been developed. Systems metabolic engineering allows successful development of microbes that are capable of producing several different biofuels including bioethanol, biobutanol, alkane, and biodiesel, and even hydrogen. In this review, the approaches employed to develop efficient biofuel producers by metabolic engineering and systems metabolic engineering approaches are reviewed with relevant example cases. It is expected that systems metabolic engineering will be employed as an essential strategy for the development of microbial strains for industrial applications. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Reverse engineering smart card malware using side channel analysis with machine learning techniques

    CSIR Research Space (South Africa)

    Djonon Tsague, Hippolyte

    2016-12-01

    Full Text Available by evaluating its power consumption only. Besides well-studied methods from side channel analysis, we apply a combination of dimensionality reduction techniques in the form of PCA and LDA models to compress the large amount of data generated while preserving...

  15. Diagnosis of Dengue Infection Using Conventional and Biosensor Based Techniques

    Science.gov (United States)

    Parkash, Om; Hanim Shueb, Rafidah

    2015-01-01

    Dengue is an arthropod-borne viral disease caused by four antigenically different serotypes of dengue virus. This disease is considered as a major public health concern around the world. Currently, there is no licensed vaccine or antiviral drug available for the prevention and treatment of dengue disease. Moreover, clinical features of dengue are indistinguishable from other infectious diseases such as malaria, chikungunya, rickettsia and leptospira. Therefore, prompt and accurate laboratory diagnostic test is urgently required for disease confirmation and patient triage. The traditional diagnostic techniques for the dengue virus are viral detection in cell culture, serological testing, and RNA amplification using reverse transcriptase PCR. This paper discusses the conventional laboratory methods used for the diagnosis of dengue during the acute and convalescent phase and highlights the advantages and limitations of these routine laboratory tests. Subsequently, the biosensor based assays developed using various transducers for the detection of dengue are also reviewed. PMID:26492265

  16. Diagnosis of Dengue Infection Using Conventional and Biosensor Based Techniques.

    Science.gov (United States)

    Parkash, Om; Shueb, Rafidah Hanim

    2015-10-19

    Dengue is an arthropod-borne viral disease caused by four antigenically different serotypes of dengue virus. This disease is considered as a major public health concern around the world. Currently, there is no licensed vaccine or antiviral drug available for the prevention and treatment of dengue disease. Moreover, clinical features of dengue are indistinguishable from other infectious diseases such as malaria, chikungunya, rickettsia and leptospira. Therefore, prompt and accurate laboratory diagnostic test is urgently required for disease confirmation and patient triage. The traditional diagnostic techniques for the dengue virus are viral detection in cell culture, serological testing, and RNA amplification using reverse transcriptase PCR. This paper discusses the conventional laboratory methods used for the diagnosis of dengue during the acute and convalescent phase and highlights the advantages and limitations of these routine laboratory tests. Subsequently, the biosensor based assays developed using various transducers for the detection of dengue are also reviewed.

  17. An RSS based location estimation technique for cognitive relay networks

    KAUST Repository

    Qaraqe, Khalid A.

    2010-11-01

    In this paper, a received signal strength (RSS) based location estimation method is proposed for a cooperative wireless relay network where the relay is a cognitive radio. We propose a method for the considered cognitive relay network to determine the location of the source using the direct and the relayed signal at the destination. We derive the Cramer-Rao lower bound (CRLB) expressions separately for x and y coordinates of the location estimate. We analyze the effects of cognitive behaviour of the relay on the performance of the proposed method. We also discuss and quantify the reliability of the location estimate using the proposed technique if the source is not stationary. The overall performance of the proposed method is presented through simulations. ©2010 IEEE.

  18. Demand Management Based on Model Predictive Control Techniques

    Directory of Open Access Journals (Sweden)

    Yasser A. Davizón

    2014-01-01

    Full Text Available Demand management (DM is the process that helps companies to sell the right product to the right customer, at the right time, and for the right price. Therefore the challenge for any company is to determine how much to sell, at what price, and to which market segment while maximizing its profits. DM also helps managers efficiently allocate undifferentiated units of capacity to the available demand with the goal of maximizing revenue. This paper introduces control system approach to demand management with dynamic pricing (DP using the model predictive control (MPC technique. In addition, we present a proper dynamical system analogy based on active suspension and a stability analysis is provided via the Lyapunov direct method.

  19. Whitelists Based Multiple Filtering Techniques in SCADA Sensor Networks

    Directory of Open Access Journals (Sweden)

    DongHo Kang

    2014-01-01

    Full Text Available Internet of Things (IoT consists of several tiny devices connected together to form a collaborative computing environment. Recently IoT technologies begin to merge with supervisory control and data acquisition (SCADA sensor networks to more efficiently gather and analyze real-time data from sensors in industrial environments. But SCADA sensor networks are becoming more and more vulnerable to cyber-attacks due to increased connectivity. To safely adopt IoT technologies in the SCADA environments, it is important to improve the security of SCADA sensor networks. In this paper we propose a multiple filtering technique based on whitelists to detect illegitimate packets. Our proposed system detects the traffic of network and application protocol attacks with a set of whitelists collected from normal traffic.

  20. Clustering economies based on multiple criteria decision making techniques

    Directory of Open Access Journals (Sweden)

    Mansour Momeni

    2011-10-01

    Full Text Available One of the primary concerns on many countries is to determine different important factors affecting economic growth. In this paper, we study some factors such as unemployment rate, inflation ratio, population growth, average annual income, etc to cluster different countries. The proposed model of this paper uses analytical hierarchy process (AHP to prioritize the criteria and then uses a K-mean technique to cluster 59 countries based on the ranked criteria into four groups. The first group includes countries with high standards such as Germany and Japan. In the second cluster, there are some developing countries with relatively good economic growth such as Saudi Arabia and Iran. The third cluster belongs to countries with faster rates of growth compared with the countries located in the second group such as China, India and Mexico. Finally, the fourth cluster includes countries with relatively very low rates of growth such as Jordan, Mali, Niger, etc.

  1. Template Metaprogramming Techniques for Concept-Based Specialization

    Directory of Open Access Journals (Sweden)

    Bruno Bachelet

    2013-01-01

    Full Text Available In generic programming, software components are parameterized on types. When available, a static specialization mechanism allows selecting, for a given set of parameters, a more suitable version of a generic component than its primary version. The normal C++ template specialization mechanism is based on the type pattern of the parameters, which is not always the best way to guide the specialization process: type patterns are missing some information on types that could be relevant to define specializations. The notion of a concept, which represents a set of requirements (including syntactic and semantic aspects for a type, is known to be an interesting approach to control template specialization. For many reasons, concepts were dropped from C++11 standard, this article therefore describes template metaprogramming techniques for declaring concepts, modeling relationships (meaning that a type fulfills the requirements of a concept, and refinement relationships (meaning that a concept refines the requirements of another concept. From a taxonomy of concepts and template specializations based on concepts, an automatic mechanism selects the most appropriate version of a generic component for a given instantiation. Our purely library-based solution is also open for retroactive extension: new concepts, relationships, and template specializations can be defined at any time; such additions will then be picked up by the specialization mechanism.

  2. Intelligent Autofeedback and Safety Early-Warning for Underground Cavern Engineering during Construction Based on BP Neural Network and FEM

    OpenAIRE

    Xu, Lei; Zhang, Taijun; Ren, Qingwen

    2015-01-01

    The low efficiency of feedback analysis is one of the main shortcomings in the construction of underground cavern engineering. With this in mind, a method of intelligent autofeedback and safety early-warning for underground cavern is proposed based on BP neural network and FEM. The training sample points are chosen by using uniform test design method, and the autogeneration of FEM calculation file for ABAQUS is realized by using the technique of file partition, information grouping, and order...

  3. An investigation of a video-based patient repositioning technique

    International Nuclear Information System (INIS)

    Yan Yulong; Song Yulin; Boyer, Arthur L.

    2002-01-01

    Purpose: We have investigated a video-based patient repositioning technique designed to use skin features for radiotherapy repositioning. We investigated the feasibility of the clinical application of this system by quantitative evaluation of performance characteristics of the methodology. Methods and Materials: Multiple regions of interest (ROI) were specified in the field of view of video cameras. We used a normalized correlation pattern-matching algorithm to compute the translations of each ROI pattern in a target image. These translations were compared against trial translations using a quadratic cost function for an optimization process in which the patient rotation and translational parameters were calculated. Results: A hierarchical search technique achieved high-speed (compute correlation for 128x128 ROI in 512x512 target image within 0.005 s) and subpixel spatial accuracy (as high as 0.2 pixel). By treating the observed translations as movements of points on the surfaces of a hypothetical cube, we were able to estimate accurately the actual translations and rotations of the test phantoms used in our experiments to less than 1 mm and 0.2 deg. with a standard deviation of 0.3 mm and 0.5 deg. respectively. For human volunteer cases, we estimated the translations and rotations to have an accuracy of 2 mm and 1.2 deg. Conclusion: A personal computer-based video system is suitable for routine patient setup of fractionated conformal radiotherapy. It is expected to achieve high-precision repositioning of the skin surface with high efficiency

  4. The Potential for Computer Based Systems in Modular Engineering

    DEFF Research Database (Denmark)

    Miller, Thomas Dedenroth

    1998-01-01

    The paper elaborates on knowledge management and the possibility for computer support of the design process of pharmaceutical production plants in relation to the ph.d. project modular engineering.......The paper elaborates on knowledge management and the possibility for computer support of the design process of pharmaceutical production plants in relation to the ph.d. project modular engineering....

  5. Laser-based diagnostics on NO in a diesel engine

    NARCIS (Netherlands)

    Brugman, Theodorus Maria

    1999-01-01

    Of all internal combustion engines diesel engines tend to be the most efficient. However, this high efficiency is coupled with specific emissions of nitric oxides (NOx = NO and NO2) and soot. Such emissions are best fought against at their very source: the diesel combustion process itself. The

  6. Novel Machine Learning-Based Techniques for Efficient Resource Allocation in Next Generation Wireless Networks

    KAUST Repository

    AlQuerm, Ismail A.

    2018-02-21

    resources management in diverse wireless networks. The core operation of the proposed architecture is decision-making for resource allocation and system’s parameters adaptation. Thus, we develop the decision-making mechanism using different artificial intelligence techniques, evaluate the performance achieved and determine the tradeoff of using one technique over the others. The techniques include decision-trees, genetic algorithm, hybrid engine based on decision-trees and case based reasoning, and supervised engine with machine learning contribution to determine the ultimate technique that suits the current environment conditions. All the proposed techniques are evaluated using testbed implementation in different topologies and scenarios. LTE networks have been considered as a potential environment for demonstration of our proposed cognitive based resource allocation techniques as they lack of radio resource management. In addition, we explore the use of enhanced online learning to perform efficient resource allocation in the upcoming 5G networks to maximize energy efficiency and data rate. The considered 5G structures are heterogeneous multi-tier networks with device to device communication and heterogeneous cloud radio access networks. We propose power and resource blocks allocation schemes to maximize energy efficiency and data rate in heterogeneous 5G networks. Moreover, traffic offloading from large cells to small cells in 5G heterogeneous networks is investigated and an online learning based traffic offloading strategy is developed to enhance energy efficiency. Energy efficiency problem in heterogeneous cloud radio access networks is tackled using online learning in centralized and distributed fashions. The proposed online learning comprises improvement features that reduce the algorithms complexities and enhance the performance achieved.

  7. CANDU in-reactor quantitative visual-based inspection techniques

    Science.gov (United States)

    Rochefort, P. A.

    2009-02-01

    This paper describes two separate visual-based inspection procedures used at CANDU nuclear power generating stations. The techniques are quantitative in nature and are delivered and operated in highly radioactive environments with access that is restrictive, and in one case is submerged. Visual-based inspections at stations are typically qualitative in nature. For example a video system will be used to search for a missing component, inspect for a broken fixture, or locate areas of excessive corrosion in a pipe. In contrast, the methods described here are used to measure characteristic component dimensions that in one case ensure ongoing safe operation of the reactor and in the other support reactor refurbishment. CANDU reactors are Pressurized Heavy Water Reactors (PHWR). The reactor vessel is a horizontal cylindrical low-pressure calandria tank approximately 6 m in diameter and length, containing heavy water as a neutron moderator. Inside the calandria, 380 horizontal fuel channels (FC) are supported at each end by integral end-shields. Each FC holds 12 fuel bundles. The heavy water primary heat transport water flows through the FC pressure tube, removing the heat from the fuel bundles and delivering it to the steam generator. The general design of the reactor governs both the type of measurements that are required and the methods to perform the measurements. The first inspection procedure is a method to remotely measure the gap between FC and other in-core horizontal components. The technique involves delivering vertically a module with a high-radiation-resistant camera and lighting into the core of a shutdown but fuelled reactor. The measurement is done using a line-of-sight technique between the components. Compensation for image perspective and viewing elevation to the measurement is required. The second inspection procedure measures flaws within the reactor's end shield FC calandria tube rolled joint area. The FC calandria tube (the outer shell of the FC) is

  8. Advanced Multipath Mitigation Techniques for Satellite-Based Positioning Applications

    Directory of Open Access Journals (Sweden)

    Mohammad Zahidul H. Bhuiyan

    2010-01-01

    Full Text Available Multipath remains a dominant source of ranging errors in Global Navigation Satellite Systems (GNSS, such as the Global Positioning System (GPS or the future European satellite navigation system Galileo. Multipath is generally considered undesirable in the context of GNSS, since the reception of multipath can make significant distortion to the shape of the correlation function used for time delay estimation. However, some wireless communications techniques exploit multipath in order to provide signal diversity though in GNSS, the major challenge is to effectively mitigate the multipath, since we are interested only in the satellite-receiver transit time offset of the Line-Of-Sight (LOS signal for the receiver's position estimate. Therefore, the multipath problem has been approached from several directions in order to mitigate the impact of multipath on navigation receivers, including the development of novel signal processing techniques. In this paper, we propose a maximum likelihood-based technique, namely, the Reduced Search Space Maximum Likelihood (RSSML delay estimator, which is capable of mitigating the multipath effects reasonably well at the expense of increased complexity. The proposed RSSML attempts to compensate the multipath error contribution by performing a nonlinear curve fit on the input correlation function, which finds a perfect match from a set of ideal reference correlation functions with certain amplitude(s, phase(s, and delay(s of the multipath signal. It also incorporates a threshold-based peak detection method, which eventually reduces the code-delay search space significantly. However, the downfall of RSSML is the memory requirement which it uses to store the reference correlation functions. The multipath performance of other delay-tracking methods previously studied for Binary Phase Shift Keying-(BPSK- and Sine Binary Offset Carrier- (SinBOC- modulated signals is also analyzed in closed loop model with the new Composite

  9. Development of Innovative Radioactive Isotope Production Techniques at the Pennsylvania State University Radiation Science and Engineering Center

    Energy Technology Data Exchange (ETDEWEB)

    Johnsen, Amanda M. [Pennsylvania State Univ., State College, PA (United States). Radiation Science and Engineering Center; Heidrich, Brenden [Pennsylvania State Univ., State College, PA (United States). Radiation Science and Engineering Center; Durrant, Chad [Pennsylvania State Univ., State College, PA (United States). Department of mechanical and Nuclear Engineering Center; Bascom, Andrew [Pennsylvania State Univ., State College, PA (United States). Department of mechanical and Nuclear Engineering Center; Unlu, Kenan [Pennsylvania State Univ., State College, PA (United States). Radiation Science and Engineering Center

    2013-08-15

    The Penn State Breazeale Nuclear Reactor (PSBR) at the Radiation Science and Engineering Center (RSEC) has produced radioisotopes for research and commercial purposes since 1956. With the rebirth of the radiochemistry education and research program at the RSEC, the Center stands poised to produce a variety of radioisotopes for research and industrial work that is in line with the mission of the DOE Office of Science, Office of Nuclear Physics, Isotope Development and Production Research and Application Program. The RSEC received funding from the Office of Science in 2010 to improve production techniques and develop new capabilities. Under this program, we improved our existing techniques to provide four radioisotopes (Mn-56, Br-82, Na-24, and Ar-41) to researchers and industry in a safe and efficient manner. The RSEC is also working to develop new innovative techniques to provide isotopes in short supply to researchers and others in the scientific community, specifically Cu-64 and Cu-67. Improving our existing radioisotopes production techniques and investigating new and innovative methods are two of the main initiatives of the radiochemistry research program at the RSEC.

  10. GIS-Based bivariate statistical techniques for groundwater potential ...

    Indian Academy of Sciences (India)

    24

    an example of Iran). Ali Haghizadeha, Davoud Davoudi Moghaddama, Hamid Reza Pourghasemib* a Department of Range and Watershed Management Engineering, Lorestan University, Lorestan, Iran b Department of Natural Resources and ...

  11. Application of system safety engineering techniques for hazard prevention at the Superconducting Super Collider

    International Nuclear Information System (INIS)

    Hendrix, B.L.

    1991-01-01

    A primary goal of the Superconducting Super Collider Laboratory (SSCL) is to establish an exemplary safety program. Achieving this goal requires leadership, planning, coordination, and technical know-how. To ensure that safety is an inherent part of the design, the Environment, Safety and Health Office employs a systems engineering discipline and process known as System Safety. The goal of System Safety - hazard prevention - is accomplished by analyzing systems to identify hazards and to evaluate design and procedural options and countermeasures to prevent, eliminate, mitigate, or control hazards and risks. Establishment of safety and human factors design criteria at the outset of the project prevents unsafe designs and safety violations, reduces risks, and helps in avoiding costly design changes later. This process requires a considerable amount of coordination with a variety of technical disciplines and safety professionals to integrate methods of hazard prevention, mitigation, and risk reduction throughout the system life-cycle

  12. Usability evaluation of an emergency department information system prototype designed using cognitive systems engineering techniques.

    Science.gov (United States)

    Clark, Lindsey N; Benda, Natalie C; Hegde, Sudeep; McGeorge, Nicolette M; Guarrera-Schick, Theresa K; Hettinger, A Zachary; LaVergne, David T; Perry, Shawna J; Wears, Robert L; Fairbanks, Rollin J; Bisantz, Ann M

    2017-04-01

    This article presents an evaluation of novel display concepts for an emergency department information system (EDIS) designed using cognitive systems engineering methods. EDISs assist emergency medicine staff with tracking patient care and ED resource allocation. Participants performed patient planning and orientation tasks using the EDIS displays and rated the display's ability to support various cognitive performance objectives along with the usability, usefulness, and predicted frequency of use for 18 system components. Mean ratings were positive for cognitive performance support objectives, usability, usefulness, and frequency of use, demonstrating the successful application of design methods to create useful and usable EDIS concepts that provide cognitive support for emergency medicine staff. Nurse and provider roles had significantly different perceptions of the usability and usefulness of certain EDIS components, suggesting that they have different information needs while working. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. An Ultra-Low Power Turning Angle Based Biomedical Signal Compression Engine with Adaptive Threshold Tuning

    Directory of Open Access Journals (Sweden)

    Jun Zhou

    2017-08-01

    Full Text Available Intelligent sensing is drastically changing our everyday life including healthcare by biomedical signal monitoring, collection, and analytics. However, long-term healthcare monitoring generates tremendous data volume and demands significant wireless transmission power, which imposes a big challenge for wearable healthcare sensors usually powered by batteries. Efficient compression engine design to reduce wireless transmission data rate with ultra-low power consumption is essential for wearable miniaturized healthcare sensor systems. This paper presents an ultra-low power biomedical signal compression engine for healthcare data sensing and analytics in the era of big data and sensor intelligence. It extracts the feature points of the biomedical signal by window-based turning angle detection. The proposed approach has low complexity and thus low power consumption while achieving a large compression ratio (CR and good quality of reconstructed signal. Near-threshold design technique is adopted to further reduce the power consumption on the circuit level. Besides, the angle threshold for compression can be adaptively tuned according to the error between the original signal and reconstructed signal to address the variation of signal characteristics from person to person or from channel to channel to meet the required signal quality with optimal CR. For demonstration, the proposed biomedical compression engine has been used and evaluated for ECG compression. It achieves an average (CR of 71.08% and percentage root-mean-square difference (PRD of 5.87% while consuming only 39 nW. Compared to several state-of-the-art ECG compression engines, the proposed design has significantly lower power consumption while achieving similar CRD and PRD, making it suitable for long-term wearable miniaturized sensor systems to sense and collect healthcare data for remote data analytics.

  14. 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

  15. Engineering applications using CAD based application programming interface

    Directory of Open Access Journals (Sweden)

    Tzotzis Anastasios

    2017-01-01

    Full Text Available Automating the design process of a product or a system can provide engineers and designers with many benefits. As such, repeatable tasks that are time consuming can be handled automatically and with minimal human attention. This is achieved by using the API (Application Programmable Interface of CAD systems in order to create macros or even develop software applications. The present paper deals with an application that has been developed with the API of a general purposes CAD system. This application automates the design process of a standard pneumatic double acting cylinder based on the appropriate inserted parameters (ISO 15552.The design process begins with the creation of a series of components developed as solids, and extends to the extraction of basic attributes and properties from the complete mechanical assembly. Finally, the assembled models and the extracted data can be used to further study the design of the pneumatic double acting cylinder. It is expected in the future to expand the features of the presented application in order to automate the design process of other related mechanical systems.

  16. Engineer Ethics

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dae Sik; Kim, Yeong Pil; Kim, Yeong Jin

    2003-03-15

    This book tells of engineer ethics such as basic understanding of engineer ethics with history of engineering as a occupation, definition of engineering and specialized job and engineering, engineer ethics as professional ethics, general principles of ethics and its limitation, ethical theory and application, technique to solve the ethical problems, responsibility, safety and danger, information engineer ethics, biotechnological ethics like artificial insemination, life reproduction, gene therapy and environmental ethics.

  17. Engineer Ethics

    International Nuclear Information System (INIS)

    Lee, Dae Sik; Kim, Yeong Pil; Kim, Yeong Jin

    2003-03-01

    This book tells of engineer ethics such as basic understanding of engineer ethics with history of engineering as a occupation, definition of engineering and specialized job and engineering, engineer ethics as professional ethics, general principles of ethics and its limitation, ethical theory and application, technique to solve the ethical problems, responsibility, safety and danger, information engineer ethics, biotechnological ethics like artificial insemination, life reproduction, gene therapy and environmental ethics.

  18. A novel technique for active vibration control, based on optimal

    Indian Academy of Sciences (India)

    In the last few decades, researchers have proposed many control techniques to suppress unwanted vibrations in a structure. In this work, a novel and simple technique is proposed for the active vibration control. In this technique, an optimal tracking control is employed to suppress vibrations in a structure by simultaneously ...

  19. Analysis of web-based online services for GPS relative and precise point positioning techniques

    Directory of Open Access Journals (Sweden)

    Taylan Ocalan

    Full Text Available Nowadays, Global Positioning System (GPS has been used effectively in several engineering applications for the survey purposes by multiple disciplines. Web-based online services developed by several organizations; which are user friendly, unlimited and most of them are free; have become a significant alternative against the high-cost scientific and commercial software on achievement of post processing and analyzing the GPS data. When centimeter (cm or decimeter (dm level accuracies are desired, that can be obtained easily regarding different quality engineering applications through these services. In this paper, a test study was conducted at ISKI-CORS network; Istanbul-Turkey in order to figure out the accuracy analysis of the most used web based online services around the world (namely OPUS, AUSPOS, SCOUT, CSRS-PPP, GAPS, APPS, magicGNSS. These services use relative and precise point positioning (PPP solution approaches. In this test study, the coordinates of eight stations were estimated by using of both online services and Bernese 5.0 scientific GPS processing software from 24-hour GPS data set and then the coordinate differences between the online services and Bernese processing software were computed. From the evaluations, it was seen that the results for each individual differences were less than 10 mm regarding relative online service, and less than 20 mm regarding precise point positioning service. The accuracy analysis was gathered from these coordinate differences and standard deviations of the obtained coordinates from different techniques and then online services were compared to each other. The results show that the position accuracies obtained by associated online services provide high accurate solutions that may be used in many engineering applications and geodetic analysis.

  20. Design of process displays based on risk analysis techniques

    International Nuclear Information System (INIS)

    Lundtang Paulsen, J.

    2004-05-01

    This thesis deals with the problems of designing display systems for process plants. We state the reasons why it is important to discuss information systems for operators in a control room, especially in view of the enormous amount of information available in computer-based supervision systems. The state of the art is discussed: How are supervision systems designed today and why? Which strategies are used? What kind of research is going on? Four different plants and their display systems, designed by the author, are described and discussed. Next we outline different methods for eliciting knowledge of a plant, particularly the risks, which is necessary information for the display designer. A chapter presents an overview of the various types of operation references: constitutive equations, set points, design parameters, component characteristics etc., and their validity in different situations. On the basis of her experience with the design of display systems; with risk analysis methods and from 8 years, as an engineer-on-shift at a research reactor, the author developed a method to elicit necessary information to the operator. The method, a combination of a Goal-Tree and a Fault-Tree, is described in some detail. Finally we address the problem of where to put the dot and the lines: when all information is on the table, how should it be presented most adequately. Included, as an appendix is a paper concerning the analysis of maintenance reports and visualization of their information. The purpose was to develop a software tool for maintenance supervision of components in a nuclear power plant. (au)