WorldWideScience

Sample records for engineering properties experiment

  1. Lunar surface engineering properties experiment definition

    Science.gov (United States)

    Mitchell, J. K.; Goodman, R. E.; Hurlbut, F. C.; Houston, W. N.; Willis, D. R.; Witherspoon, P. A.; Hovland, H. J.

    1971-01-01

    Research on the mechanics of lunar soils and on developing probes to determine the properties of lunar surface materials is summarized. The areas of investigation include the following: soil simulation, soil property determination using an impact penetrometer, soil stabilization using urethane foam or phenolic resin, effects of rolling boulders down lunar slopes, design of borehole jack and its use in determining failure mechanisms and properties of rocks, and development of a permeability probe for measuring fluid flow through porous lunar surface materials.

  2. Engineering spray-dried rosemary extracts with improved physicomechanical properties: a design of experiments issue

    Directory of Open Access Journals (Sweden)

    Luiza T. Chaul

    Full Text Available ABSTRACT A 33 Box–Behnken design and Response Surface Methodology were performed to evaluate the influence of extract feed rate, drying air inlet temperature and spray nozzle airflow rate on the process yield, stability parameters (moisture content and water activity and on several physicomechanical properties of spray-dried rosemary extracts. Powder yield ranged from 17.1 to 74.96%. The spray-dried rosemary extracts showed moisture content and water activity below 5% and 0.5%, respectively, which indicate their chemical and microbiological stabilities. Even without using drying aids, some sets of experimental conditions rendered dried products with suitable flowability and compressibility characteristics for direct preparation of solid dosage forms. Analysis of variance and Response Surface Methodology proved that studied factors significantly affected most of the spray-dried rosemary extract quality indicators at different levels. The main processing parameter affecting the spray-dried rosemary extract characteristics was inlet temperature. The best combination of parameters used to obtain a reasonable yield of stable dry rosemary extracts with adequate technological properties for pharmaceutical purpose involves an extract feed rate of 2 ml/min, 80 °C inlet temperature and 40 l/min SA. The design of experiments approach is an interesting strategy for engineering spray-dried rosemary extracts with improved characteristics for pharmaceutical industrial purpose.

  3. Subterranean stress engineering experiments

    International Nuclear Information System (INIS)

    Campbell, J.R.; Colgate, S.A.; Wheat, B.M.

    1980-01-01

    The state of stress in a subterranean rock mass has classically been assumed to be constant at best. In soil with a high clay content, preconsolidation and drainage methods can lead to more stable foundation material, but methods for engineering the stresses in large masses of rock are not well known. This paper shows the results from an experiment designed to alter the in situ rock stress field in an oil shale mine. This was done by hydrofracturing the rock by use of a packed-well injection system and then propping the crack open with a thixotropic gel, which slowly hardened to the consistency of cement. Successive hydrofracture and high-pressure grouting resulted in an overstressed region. Well-head injection pressures, surface tilts, injection rates, and subterranean strains were measured and recorded on floppy disk by a Z-80 microprocessor. The results were then transmitted to the large computer system at the Los Alamos Scientific Laboratory (LASL). To put the data in a more useful form, computer-generated movies of the tilts and strains were made by use of computer graphics developed at LASL. The purpose of this paper is to present results from the Single Large Instrumented Test conducted in the Colony Oil Shale Mine near Rifle, Colorado. 13 figures

  4. Collaborative engineering experiences

    NARCIS (Netherlands)

    Ir. Peter van Kollenburg; Dr. Ir. P. Mulders; Ir. Dick van Schenk Brill; Dr. Ir. G. Schouten; Dr. J. Ochs

    2000-01-01

    In the fall of 1999, an international integrated product development pilot project based on collaborative engineering was started with team members in two international teams from the United States, The Netherlands and Germany. Team members interacted using various Internet capabilities, including,

  5. Teaching Knowledge Engineering: Experiences

    DEFF Research Database (Denmark)

    Andersen, Tom; Hartvig, Susanne C

    1998-01-01

    Includes description of experiences gained by teaching KE in construction domains. It outlines good starting points and overall guidance to education in applied AI.......Includes description of experiences gained by teaching KE in construction domains. It outlines good starting points and overall guidance to education in applied AI....

  6. A primer of statistical methods for correlating parameters and properties of electrospun poly(L-lactide) scaffolds for tissue engineering--PART 1: design of experiments.

    Science.gov (United States)

    Seyedmahmoud, Rasoul; Rainer, Alberto; Mozetic, Pamela; Maria Giannitelli, Sara; Trombetta, Marcella; Traversa, Enrico; Licoccia, Silvia; Rinaldi, Antonio

    2015-01-01

    Tissue engineering scaffolds produced by electrospinning are of enormous interest, but still lack a true understanding about the fundamental connection between the outstanding functional properties, the architecture, the mechanical properties, and the process parameters. Fragmentary results from several parametric studies only render some partial insights that are hard to compare and generally miss the role of parameters interactions. To bridge this gap, this article (Part-1 of 2) features a case study on poly-L-lactide scaffolds to demonstrate how statistical methods such as design of experiments can quantitatively identify the correlations existing between key scaffold properties and control parameters, in a systematic, consistent, and comprehensive manner disentangling main effects from interactions. The morphological properties (i.e., fiber distribution and porosity) and mechanical properties (Young's modulus) are "charted" as a function of molecular weight (MW) and other electrospinning process parameters (the Xs), considering the single effect as well as interactions between Xs. For the first time, the major role of the MW emerges clearly in controlling all scaffold properties. The correlation between mechanical and morphological properties is also addressed. © 2014 Wiley Periodicals, Inc.

  7. A primer of statistical methods for correlating parameters and properties of electrospun poly(l -lactide) scaffolds for tissue engineering-PART 1: Design of experiments

    KAUST Repository

    Seyedmahmoud, Rasoul

    2014-03-20

    Tissue engineering scaffolds produced by electrospinning are of enormous interest, but still lack a true understanding about the fundamental connection between the outstanding functional properties, the architecture, the mechanical properties, and the process parameters. Fragmentary results from several parametric studies only render some partial insights that are hard to compare and generally miss the role of parameters interactions. To bridge this gap, this article (Part-1 of 2) features a case study on poly-l-lactide scaffolds to demonstrate how statistical methods such as design of experiments can quantitatively identify the correlations existing between key scaffold properties and control parameters, in a systematic, consistent, and comprehensive manner disentangling main effects from interactions. The morphological properties (i.e., fiber distribution and porosity) and mechanical properties (Young\\'s modulus) are "charted" as a function of molecular weight (MW) and other electrospinning process parameters (the Xs), considering the single effect as well as interactions between Xs. For the first time, the major role of the MW emerges clearly in controlling all scaffold properties. The correlation between mechanical and morphological properties is also addressed.

  8. Aerospace engineering training: universities experience

    Directory of Open Access Journals (Sweden)

    Mertins Kseniya

    2016-01-01

    Full Text Available Contemporary professional working in aerospace engineering must have a set of soft and hard skills. The experience gained in universities shows that training of a competent professional is impossible without an employer involved in this process. The paper provides an analysis of missions, tasks and experience of aerospace professionals and identifies the present and future roles, missions and required skills of a highly qualified specialist in aerospace engineering. This analysis can be used to design a master’s program aiming at providing students with the required knowledge, know-how and attitudes needed to succeed as professionals in industrial companies.

  9. Thermal Property Engineering: Exploiting the Properties of Ceramic Nanocomposites

    Science.gov (United States)

    2018-03-01

    ARL-TR-8308 ● MAR 2018 US Army Research Laboratory Thermal Property Engineering : Exploiting the Properties of Ceramic...return it to the originator. ARL-TR-8308 ● MAR 2018 US Army Research Laboratory Thermal Property Engineering : Exploiting the...2015 – Dec 31 2017 4. TITLE AND SUBTITLE Thermal Property Engineering : Exploiting the Properties of Ceramic Nanocomposites 5a. CONTRACT NUMBER 5b

  10. Engineering Sustainable Engineers through the Undergraduate Experience

    Science.gov (United States)

    Weatherton, Yvette Pearson; Sattler, Melanie; Mattingly, Stephen; Chen, Victoria; Rogers, Jamie; Dennis, Brian

    2012-01-01

    In order to meet the challenges of sustainable development, our approach to education must be modified to equip students to evaluate alternatives and devise solutions that meet multi-faceted requirements. In 2009, faculty in the Departments of Civil, Industrial and Mechanical Engineering at the University of Texas at Arlington began implementation…

  11. Safety engineering experiments of explosives

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, Noboru

    1987-07-24

    The outline of large scale experiments carried out every year since 1969 to obtain fundamental data and then establish the safety engineering standards concerning the manufacturing, storage and transportation, etc. of all explosives was described. Because it becomes recently difficult to ensure the safety distance in powder magazines and powder plants, the sandwich structure with sand is thought to be suitable as the neighboring barrier walls. The special vertical structure for embankments to provide against a emergency explosion is effective to absorb the blast. Explosion behaviors such as initiating sensitivity, detonation, sympathetic detonation, and shock occurence of the ANFO explosives in place of dynamite and the slurry explosives were studied. The safety engineering standards for the manufacturing and application of explosives were studied to establish because accidents by tabacco fire are not still distinguished. Much data concerning early stage fire fighting, a large quantity of flooding and shock occurence from a assumption of ignition during machining in the propellants manufacturing plant, could be obtained. Basic studies were made to prevent pollution in blasting sites. Collected data are utilized for the safety administration after sufficient discussion. (4 figs, 2 tabs, 3 photos, 17 refs)

  12. Technical problems and future underground engineering experiments

    Energy Technology Data Exchange (ETDEWEB)

    Higgins, G H [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

    1969-07-01

    The technical problems to be solved in future underground engineering experiments are of two kinds. One concerns adequate description of the variation of nuclear explosion effects with physical nd chemical properties of the explosion site. The other concerns engineering of the explosive detonation system to provide adequate safety and security, concurrently with minimum total costs per explosion. The semiempirical equations for explosion effects can be trusted only in the range of explosive energy, depth of burst, and rock type for which there is prior experience. Effects calculations based on the principles of continuum mechanics and measurable geophysical properties appear to work in the few test cases, such as Gasbuggy, to which they have been applied. These calculational methods must be tested in a variety of situations. The relevance of dynamic and static measurements on Dragon Trail, Bronco, Rulison, Stoop, Ketch, and Pinedale to proving the methods are discussed in this paper. The traditional methods of assembling and fielding nuclear explosives have evolved from practice at the Nevada Test Site. These provide great flexibility and assure maximum recovery of all data from each test, thus minimizing the time required to achieve desired results. Timing and firing, radiation monitoring, explosives assembly and emplacement, explosive performance, weather monitoring, and dynamic measurements of earth and building motion have all been handled traditionally as independent functions. To achieve lower costs in underground engineering experiments and projects, one prototype system combining all electronic, measurement, and communication functions is being built. Much further work will be required to complete this effort, including, especially, an examination of safety criteria and means for assuring operational and public safety at reduced costs. (author)

  13. Technical problems and future underground engineering experiments

    International Nuclear Information System (INIS)

    Higgins, G.H.

    1969-01-01

    The technical problems to be solved in future underground engineering experiments are of two kinds. One concerns adequate description of the variation of nuclear explosion effects with physical nd chemical properties of the explosion site. The other concerns engineering of the explosive detonation system to provide adequate safety and security, concurrently with minimum total costs per explosion. The semiempirical equations for explosion effects can be trusted only in the range of explosive energy, depth of burst, and rock type for which there is prior experience. Effects calculations based on the principles of continuum mechanics and measurable geophysical properties appear to work in the few test cases, such as Gasbuggy, to which they have been applied. These calculational methods must be tested in a variety of situations. The relevance of dynamic and static measurements on Dragon Trail, Bronco, Rulison, Stoop, Ketch, and Pinedale to proving the methods are discussed in this paper. The traditional methods of assembling and fielding nuclear explosives have evolved from practice at the Nevada Test Site. These provide great flexibility and assure maximum recovery of all data from each test, thus minimizing the time required to achieve desired results. Timing and firing, radiation monitoring, explosives assembly and emplacement, explosive performance, weather monitoring, and dynamic measurements of earth and building motion have all been handled traditionally as independent functions. To achieve lower costs in underground engineering experiments and projects, one prototype system combining all electronic, measurement, and communication functions is being built. Much further work will be required to complete this effort, including, especially, an examination of safety criteria and means for assuring operational and public safety at reduced costs. (author)

  14. Drying characteristics and engineering properties of fermented ...

    African Journals Online (AJOL)

    The effect of variety on the drying and engineering properties of fermented ground cassava was studied in order to generate data for design and optimum performance of various dryers used in cassava processing. This research attempts to provide data on the engineering properties such as moisture content, specific heat ...

  15. Infusing Real World Experiences into Engineering Education

    Science.gov (United States)

    National Academies Press, 2012

    2012-01-01

    The aim of this report is to encourage enhanced richness and relevance of the undergraduate engineering education experience, and thus produce better-prepared and more globally competitive graduates, by providing practical guidance for incorporating real world experience in US engineering programs. The report, a collaborative effort of the…

  16. Design of experiments in production engineering

    CERN Document Server

    2016-01-01

    This book covers design of experiments (DoE) applied in production engineering as a combination of manufacturing technology with applied management science. It presents recent research advances and applications of design experiments in production engineering and the chapters cover metal cutting tools, soft computing for modelling and optmization of machining, waterjet machining of high performance ceramics, among others.

  17. Metrology and properties of engineering surfaces

    CERN Document Server

    Greenwood, J; Chetwynd, D

    2001-01-01

    Metrology and Properties of Engineering Surfaces provides in a single volume a comprehensive and authoritative treatment of the crucial topics involved in the metrology and properties of engineering surfaces. The subject matter is a central issue in manufacturing technology, since the quality and reliability of manufactured components depend greatly upon the selection and qualities of the appropriate materials as ascertained through measurement. The book can in broad terms be split into two parts; the first deals with the metrology of engineering surfaces and covers the important issues relating to the measurement and characterization of surfaces in both two and three dimensions. This covers topics such as filtering, power spectral densities, autocorrelation functions and the use of Fractals in topography. A significant proportion is dedicated to the calibration of scanning probe microscopes using the latest techniques. The remainder of the book deals with the properties of engineering surfaces and covers a w...

  18. Advancing intercultural competency: Canadian engineering employers' experiences with immigrant engineers

    Science.gov (United States)

    Friesen, Marcia; Ingram, Sandra

    2013-05-01

    This paper explores Canadian engineering employers' perceptions of and experiences with internationally educated engineers (recent immigrants to Canada) employed in their organisations for varying lengths of time. Qualitative data were collected from employers using focus group methodology. Findings reflected employers' observations of culturally different behaviours and characteristics in their internationally educated employees, employers' reactions to cultural differences ranging from negative attributions to tolerance, and the implementation of largely ad hoc intra-organisational strategies for managing cultural differences in employer-employee relationships. Findings exposed the lack of corporate intercultural competency in the Canadian engineering profession. Equity and gatekeeping implications are discussed.

  19. Early wind engineering experiments in Denmark

    DEFF Research Database (Denmark)

    Larose, Guy; Franck, Niels

    1997-01-01

    A review of works by Danish wind engineers is presented to commemorate the 100th year anniversary of the first wind tunnel experiments. Pioneer tests by Irminger and Nøkkentved in "artificial" wind on scaled models are described. The early experiments aimed at measuring the surface pressure......" that governs today´s wind engineering practice and gave birth to the boundary layer wind tunnel....

  20. Remote Experiments in Control Engineering Education Laboratory

    Directory of Open Access Journals (Sweden)

    Milica B Naumović

    2008-05-01

    Full Text Available This paper presents Automatic Control Engineering Laboratory (ACEL - WebLab, an under-developed, internet-based remote laboratory for control engineering education at the Faculty of Electronic Engineering in Niš. Up to now, the remote laboratory integrates two physical systems (velocity servo system and magnetic levitation system and enables some levels of measurement and control. To perform experiments in ACEL-WebLab, the "LabVIEW Run Time Engine"and a standard web browser are needed.

  1. General Properties for an Agrawal Thermal Engine

    Science.gov (United States)

    Paéz-Hernández, Ricardo T.; Chimal-Eguía, Juan Carlos; Sánchez-Salas, Norma; Ladino-Luna, Delfino

    2018-04-01

    This paper presents a general property of endoreversible thermal engines known as the Semisum property previously studied in a finite-time thermodynamics context for a Curzon-Ahlborn (CA) engine but now extended to a simplified version of the CA engine studied by Agrawal in 2009 (A simplified version of the Curzon-Ahlborn engine, European Journal of Physics 30 (2009), 1173). By building the Ecological function, proposed by Angulo-Brown (An ecological optimization criterion for finite-time heat engines, Journal of Applied Physics 69 (1991), 7465-7469) in 1991, and considering two heat transfer laws an analytical expression is obtained for efficiency and power output which depends only on the heat reservoirs' temperature. When comparing the existing efficiency values of real power plants and the theoretical efficiencies obtained in this work, it is observed that the Semisum property is satisfied. Moreover, for the Newton and the Dulong-Petit heat transfer laws the existence of the g function is demonstrated and we confirm that in a Carnot-type thermal engine there is a general property independent of the heat transfer law used between the thermal reservoirs and the working substance.

  2. Centrifugal Pump Experiment for Chemical Engineering Undergraduates

    Science.gov (United States)

    Vanderslice, Nicholas; Oberto, Richard; Marrero, Thomas R.

    2012-01-01

    The purpose of this paper is to describe a Centrifugal Pump Experiment that provided an experiential learning experience to chemical engineering undergraduates at the University of Missouri in the spring of 2010 in the Unit Operations Laboratory course. Lab equipment was used by senior students with computer-based data and control technology. In…

  3. Engineering properties of fly ash concrete

    International Nuclear Information System (INIS)

    Hilmi Mahmud

    1999-01-01

    This paper presents some of the engineering properties of Malaysian fly ash concrete. Workability, compressive, flexural, tensile splitting, drying shrinkage, elastic modulus and non destructive tests were performed on fly ash and control OPC concrete specimens. Data show that concrete containing 25% fly ash replacement of cement exhibit superior or similar engineering properties to that normal concrete without fly ash. These encouraging results demonstrated the technical merits of incorporating fly ash in concrete and should pave the way for wide scale use of this versatile material in the Malaysian construction industry. (author)

  4. E-Standards For Mass Properties Engineering

    Science.gov (United States)

    Cerro, Jeffrey A.

    2008-01-01

    A proposal is put forth to promote the concept of a Society of Allied Weight Engineers developed voluntary consensus standard for mass properties engineering. This standard would be an e-standard, and would encompass data, data manipulation, and reporting functionality. The standard would be implemented via an open-source SAWE distribution site with full SAWE member body access. Engineering societies and global standards initiatives are progressing toward modern engineering standards, which become functioning deliverable data sets. These data sets, if properly standardized, will integrate easily between supplier and customer enabling technically precise mass properties data exchange. The concepts of object-oriented programming support all of these requirements, and the use of a JavaTx based open-source development initiative is proposed. Results are reported for activity sponsored by the NASA Langley Research Center Innovation Institute to scope out requirements for developing a mass properties engineering e-standard. An initial software distribution is proposed. Upon completion, an open-source application programming interface will be available to SAWE members for the development of more specific programming requirements that are tailored to company and project requirements. A fully functioning application programming interface will permit code extension via company proprietary techniques, as well as through continued open-source initiatives.

  5. Computational Experiments for Science and Engineering Education

    Science.gov (United States)

    Xie, Charles

    2011-01-01

    How to integrate simulation-based engineering and science (SBES) into the science curriculum smoothly is a challenging question. For the importance of SBES to be appreciated, the core value of simulations-that they help people understand natural phenomena and solve engineering problems-must be taught. A strategy to achieve this goal is to introduce computational experiments to the science curriculum to replace or supplement textbook illustrations and exercises and to complement or frame hands-on or wet lab experiments. In this way, students will have an opportunity to learn about SBES without compromising other learning goals required by the standards and teachers will welcome these tools as they strengthen what they are already teaching. This paper demonstrates this idea using a number of examples in physics, chemistry, and engineering. These exemplary computational experiments show that it is possible to create a curriculum that is both deeper and wider.

  6. Drying characteristics and engineering properties of fermented ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-03-06

    Mar 6, 2009 ... fermented ground cassava. J. T. Nwabanne ... The drying characteristics of fermented ground local variety of ... effect of variety on the drying and engineering properties of fermented .... Figure 2 shows that the bulk density of each cultivar ... very close thermal conductivities as depicted in the shape of Figure ...

  7. University Experiences and Women Engineering Student Persistence

    Science.gov (United States)

    Ayers, LoAnn Debra Gienger

    Riverside University (a pseudonym), like many universities, has not significantly increased the number of women who graduate with bachelor's degrees in engineering. The purpose of the study is to understand how the university experiences of women students influence the decision to persist in an undergraduate engineering degree and to understand the role of self-perception in how the students perceive experiences as supporting or hindering their persistence in the major. Archival data, documents and artifacts, observations, individual interviews, and a focus group with women engineering students provide insights into students' perceived barriers and supports of student success. Analysis of the data results in two major themes. First, students' self-confidence and self-efficacy influence how women assimilate university experiences as either supportive or diminishing of academic success. Second, university policies and practices shape the campus environment within which student experiences are formed and influence a student's level of institutional, academic, and social integration. The results of the study indicate opportunities for university leadership to enhance strategies that positively shape students' institutional, academic and social integration as precursors toward increasing the number of women students who successfully complete undergraduate engineering degrees at Riverside University. Future research is indicated to better understand how gender and gender identity intersects with other demographic factors, such as socio-economic status, immigration status, and life stage (e.g., traditional versus non-traditional students), to support or deter the persistence of engineering students to degree completion.

  8. PVD TBC experience on GE aircraft engines

    Science.gov (United States)

    Maricocchi, Antonio; Bartz, Andi; Wortman, David

    1995-01-01

    The higher performance levels of modern gas turbine engines present significant challenges in the reliability of materials in the turbine. The increased engine temperatures required to achieve the higher performance levels reduce the strength of the materials used in the turbine sections of the engine. Various forms of thermal barrier coatings (TBC's) have been used for many years to increase the reliability of gas turbine engine components. Recent experience with the physical vapor deposition (PVD) process using ceramic material has demonstrated success in extending the service life of turbine blades and nozzles. Engine test results of turbine components with a 125 micron (0.005 in) PVD TBC have demonstrated component operating temperatures of 56-83 C (100-150 F) lower than non-PVD TBC components. Engine testing has also revealed the TBC is susceptible to high angle particle impact damage. Sand particles and other engine debris impact the TBC surface at the leading edge of airfoils and fracture the PVD columns. As the impacting continues, the TBC erodes away in local areas. Analysis of the eroded areas has shown a slight increase in temperature over a fully coated area, however a significant temperature reduction was realized over an airfoil without TBC.

  9. National Educators' Workshop. Update 92: Standard Experiments in Engineering Materials Science and Technology

    Science.gov (United States)

    Gardner, James E. (Compiler); Jacobs, James A. (Compiler); Craig, Douglas F. (Compiler)

    1993-01-01

    This document contains a collection of experiments presented and demonstrated at the workshop. The experiments related to the nature and properties of engineering materials and provided information to assist in teaching about materials in the education community.

  10. Engineered Proteins: Redox Properties and Their Applications

    Science.gov (United States)

    Prabhulkar, Shradha; Tian, Hui; Wang, Xiaotang; Zhu, Jun-Jie

    2012-01-01

    Abstract Oxidoreductases and metalloproteins, representing more than one third of all known proteins, serve as significant catalysts for numerous biological processes that involve electron transfers such as photosynthesis, respiration, metabolism, and molecular signaling. The functional properties of the oxidoreductases/metalloproteins are determined by the nature of their redox centers. Protein engineering is a powerful approach that is used to incorporate biological and abiological redox cofactors as well as novel enzymes and redox proteins with predictable structures and desirable functions for important biological and chemical applications. The methods of protein engineering, mainly rational design, directed evolution, protein surface modifications, and domain shuffling, have allowed the creation and study of a number of redox proteins. This review presents a selection of engineered redox proteins achieved through these methods, resulting in a manipulation in redox potentials, an increase in electron-transfer efficiency, and an expansion of native proteins by de novo design. Such engineered/modified redox proteins with desired properties have led to a broad spectrum of practical applications, ranging from biosensors, biofuel cells, to pharmaceuticals and hybrid catalysis. Glucose biosensors are one of the most successful products in enzyme electrochemistry, with reconstituted glucose oxidase achieving effective electrical communication with the sensor electrode; direct electron-transfer-type biofuel cells are developed to avoid thermodynamic loss and mediator leakage; and fusion proteins of P450s and redox partners make the biocatalytic generation of drug metabolites possible. In summary, this review includes the properties and applications of the engineered redox proteins as well as their significance and great potential in the exploration of bioelectrochemical sensing devices. Antioxid. Redox Signal. 17, 1796–1822. PMID:22435347

  11. Remote Communication Engineering Experiments Through Internet

    Directory of Open Access Journals (Sweden)

    A. K. Gogoi

    2006-02-01

    Full Text Available In technical education, laboratory components comprise an essential and integral part without which engineering education remains incomplete. Experiments conducted on laboratory equipments lend a practical touch to the theoretical knowledge acquired by the students. However, setting up a specialized laboratory consisting of sophisticated and expensive equipments such as Digital Storage Oscilloscope, Signal Generator, Spectrum Analyzer and Network Analyzer is an expensive and unaffordable proposition for many universities and engineering colleges. Sophisticated technologies incorporated in recent models of such high-end equipments enable remote access through Internet to the instruments. This concept of accessing these expensive instruments over the Internet can be exploited by setting up a Remote Laboratory. This remote laboratory system aims at not only providing an opportunity to students from distant places to conduct hardware experiments but also to take the corresponding measurements. In this work, real-time hardware experiments have been designed and implemented. These are based on modulation techniques widely employed in Communication Engineering. An interactive Graphical User Interface (GUI environment has also been developed using Microsoft Visual Basic. This GUI is provided at the user end to facilitate the remote control and access of various instruments and experiment setups. It has been specifically designed and optimized for a low-bandwidth remote access link. The above mentioned system, as a whole, uses real-time capture of images and data from the instruments to perform experiment-related measurements.

  12. Engineering properties of inorganic polymer concretes (IPCs)

    International Nuclear Information System (INIS)

    Sofi, M.; Deventer, J.S.J. van; Mendis, P.A.; Lukey, G.C.

    2007-01-01

    This paper presents the engineering properties of inorganic polymer concretes (IPCs) with a compressive strength of 50 MPa. The study includes a determination of the modulus of elasticity, Poisson's ratio, compressive strength, and the splitting tensile strength and flexural strength of IPCs, formulated using three different sources of Class-F fly ash. Six IPC mix designs were adopted to evaluate the effects of the inclusion of coarse aggregates and granulated blast furnace slag into the mixes. A total of 90 cylindrical and 24 small beam specimens were investigated, and all tests were carried out pursuant to the relevant Australian Standards. Although some variability between the mixes was observed, the results show that, in most cases, the engineering properties of IPCs compare favorably to those predicted by the relevant Australian Standards for concrete mixtures

  13. Hygroscopic properties of Diesel engine soot particles

    Energy Technology Data Exchange (ETDEWEB)

    Weingartner, E.; Baltensperger, U. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Burtscher, H. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-11-01

    The hygroscopic properties of combustion particles, freshly emitted from a Diesel engine were investigated. It was found that these particles start to grow by water condensation at a relative humidity (RH)>80%. The hygroscopicity of these particles was enhanced when the sulfur content of the fuel was increased or when the particles were artificially aged (i.e. particles were subjected to an ozone or UV pre-treatment). (author) 2 figs., 5 refs.

  14. Engineered Asymmetric Composite Membranes with Rectifying Properties.

    Science.gov (United States)

    Wen, Liping; Xiao, Kai; Sainath, Annadanam V Sesha; Komura, Motonori; Kong, Xiang-Yu; Xie, Ganhua; Zhang, Zhen; Tian, Ye; Iyoda, Tomokazu; Jiang, Lei

    2016-01-27

    Asymmetric composite membranes with rectifying properties are developed by grafting pH-stimulus-responsive materials onto the top layer of the composite structure, which is prepared by two novel block copolymers using a phase-separation technique. This engineered asymmetric composite membrane shows potential applications in sensors, filtration, and nanofluidic devices. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. A primer of statistical methods for correlating parameters and properties of electrospun poly(l -lactide) scaffolds for tissue engineering-PART 1: Design of experiments

    KAUST Repository

    Seyedmahmoud, Rasoul; Rainer, Alberto; Mozetic, Pamela; Maria Giannitelli, Sara; Trombetta, Marcella; Traversa, Enrico; Licoccia, Silvia; Rinaldi, Antonio

    2014-01-01

    parameters (the Xs), considering the single effect as well as interactions between Xs. For the first time, the major role of the MW emerges clearly in controlling all scaffold properties. The correlation between mechanical and morphological properties is also

  16. Engineering-scale dust control experiments

    International Nuclear Information System (INIS)

    Winberg, M.R.; Pawelko, R.J.; Jacobs, N.C.; Thompson, D.N.

    1990-12-01

    This report presents the results of engineering scale dust-control experiments relating to contamination control during handling of transuranic waste. These experiments focused on controlling dust during retrieval operations of buried waste where waste and soil are intimately mixed. Sources of dust generation during retrieval operations include digging, dumping, and vehicle traffic. Because contaminants are expected to attach to soil particles and move with the generated dust, control of the dust spread may be the key to contamination control. Dust control techniques examined in these experiments include the use of misting systems, soil fixatives, and dust suppression agents. The Dryfog Ultrasonic Misting Head, manufactured by Sonics, Incorporated, and ENTAC, an organic resin derived from tree sap manufactured by ENTAC Corporation, were tested. The results of the experiments include product performance and recommended application methods. 19 figs., 7 refs., 6 tabs

  17. Engineering electrical properties of graphene: chemical approaches

    International Nuclear Information System (INIS)

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

    2015-01-01

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

  18. Teaching Ethics to Engineers: A Socratic Experience.

    Science.gov (United States)

    Génova, Gonzalo; González, M Rosario

    2016-04-01

    In this paper we present the authors' experience of teaching a course in Ethics for Engineers, which has been delivered four times in three different universities in Spain and Chile. We begin by presenting the material context of the course (its place within the university program, the number of students attending, its duration, etc.), and especially the intellectual background of the participating students, in terms of their previous understanding of philosophy in general, and of ethics in particular. Next we set out the objectives of the course and the main topics addressed, as well as the methodology and teaching resources employed to have students achieve a genuine philosophical reflection on the ethical aspects of the profession, starting from their own mindset as engineers. Finally we offer some results based on opinion surveys of the students, as well as a more personal assessment by the authors, recapitulating the most significant achievements of the course and indicating its underlying Socratic structure.

  19. Design of Experiments for Food Engineering

    DEFF Research Database (Denmark)

    Pedersen, Søren Juhl; Geoffrey Vining, G.

    This work looks at the application of Design of Experiments (DoE) to Food Engineering (FE) problems in relation to quality. The field of Quality Engineering (QE) is a natural partnering field for FE due to the extensive developments that QE has had in using DoE for quality improvement especially...... in manufacturing industries. In the thesis the concepts concerning food quality is addressed and in addition how QE proposes to define quality. There is seen a merger in how QE’s definition of quality has been translated for food. At the same time within FE a divergence has been proposed in the literature...... that the fundamental principles of DoE have as much importance and relevance as ever for both the food industry and FE research....

  20. Teenage experiments contaminate suburban property

    International Nuclear Information System (INIS)

    Lall, P.; Jensen, L.; Mitchell, J.; Sass, W.; Skowronek, R.; Minnaar, D.

    1999-01-01

    In August 1994, 18-year-old David Hahn (David) was detained by police in Clinton Township, Michigan. When the police searched his car, they discovered a locked tool box and other containers that David said contained radioactive materials resulting from experiments he had conducted with the radioactive materials from, primarily, consumer products. From the ages 14 to 18, David spent his spare time at his Union Lake, Michigan, home attempting to concentrate, bum, chemically alter, and experiment with: the thorium from hundreds of lantern mantles, radium from various luminescent sources and clock dials, americium from smoke detector sources, and radioactive materials from natural ores. In the process, he had contaminated a wooden shed in his backyard and his bedroom, and exposed himself. In 1995, EPA, their emergency response contractor, and the Michigan Department of Public Health (MDPH) performed an emergency assessment and removal at the property. The response and removal were conducted cost-effectively and generated approximately 10 cubic yards of radioactive waste. (author)

  1. First Experiences with Google Earth Engine

    OpenAIRE

    Navarro, José A.

    2017-01-01

    This paper presents the first experiences of the author with GEE (Google Earth Engine). A C++ image processing algorithm, still under development, was migrated to this new environment using GEE’s web interface and the JavaScript language. The idea is to discover the problems that might arise when migrating to this environment as well as to assess the presumable performance boost that should be achieved. A reduced—more didactic—version of the aforementioned algorithm is presented in a step-by-...

  2. ENGINEERING GEOLOGY PROPERTIES OF 'KONJSKO' TUNNEL

    Directory of Open Access Journals (Sweden)

    Ivan Grabovac

    2004-12-01

    Full Text Available Investigation works for the design of the Konjsko Tunnel with two pipes, part of the Split-Zagreb Motorway, provided relevant data on rock mass and soil properties for construction of the prognose engineering-geological longitudinal sections. West tunnel portals are situated in tectonically deformed and partly dynamically metamorphosed Eocene flysch marls, while east ones are located in Senonian limestones. There is an overthrust contact between flysch marls and limestones. With the beginning of the excavations, rock mass characteristics were regularly registered after each blasting and actual longitudinal engineering-geological cross-sections were constructed as well as cross-sections of the excavation face. There were some differences between prognosticated and registered sections since it was infeasible to accurately determine the dip of the overthrust plane that was at shallow depth below the tunnel grade line and also due to the occurrence of transversal faults that intersected the overthrust. Data collected before and during the tunnel construction complemented the knowledge on geological structure of the surroundings and physical-mechanical characteristics of strata (the paper is published in Croatian.

  3. Biofuel properties and combustion experiences

    Energy Technology Data Exchange (ETDEWEB)

    Sander, B [Faelleskemikerne, Elsamprojekt A/S, Fredericia (Denmark)

    1996-12-01

    In Denmark the electric utility groups ELSAM and ELKRAFT are, due to government demands, obliged to utilize large amounts of biomass for power production. By the year 2000, 1,200,000 tonnes of straw and 200,000 tonnes of wood chips will be used annually. This paper gives an overview of the fuel properties of Danish straw and wood chips compared with coal. It is shown that straw has a much higher content of potassium and chlorine than wood chips and coal and this causes a number of serious technical problems in power production plants. Therefore, it has been investigated whether it is possible to reduce the content of potassium and chlorine in straw from the field. Cultivation trials have been carried out in the growing seasons of 1993, 1994 and 1995. In the first year it was investigated how different cultivation factors influence the chemical composition of straw. In the two following year the aim was to study how the chlorine supply from fertilizers influences the straw composition and it was shown that the chlorine content of straw can be reduced by using chlorine-free fertilizers. Use of straw as a fuel in existing pulverized coal-fired units may be accomplished by co-firing straw and coal in the boiler or by establishing a separate grate-fired boiler for straw and wood chips which supplies steam to the steam turbine of the coal-fired power plant. This paper describes some of the experiences with emissions, residues and deposit formation which have been gained for these types of plants in Denmark. (au)

  4. Experience Engineering: An Engineering Course for Non-Majors

    Science.gov (United States)

    Hargrove-Leak, Sirena

    2012-01-01

    The engineering profession continues to struggle to attract new talent, in part because it is not well understood by the general public and often viewed in a negative light. Therefore, engineering professionals have called for new approaches promote better understanding and change negative perceptions. One suggested approach is for engineering…

  5. 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.

  6. Experiments on common property management

    NARCIS (Netherlands)

    van Soest, D.P.; Shogren, J.F.

    2013-01-01

    Common property resources are (renewable) natural resources where current excessive extraction reduces future resource availability, and the use of which is de facto restricted to a specific set of agents, such as inhabitants of a village or members of a community; think of community-owned forests,

  7. Investigation of students' experiences of gendered cultures in engineering workplaces

    Science.gov (United States)

    Male, Sally A.; Gardner, Anne; Figueroa, Eugenia; Bennett, Dawn

    2018-05-01

    Women remain severely under-represented in engineering in Australia as in all Western countries. This limits the pool of talent, standpoints and approaches within the profession. Furthermore, this under-representation equates to restriction of the benefits of being an engineer mainly to men. Gendered workplace experiences have been found to contribute to women leaving the profession. In this study we explore students' experiences of gendered cultures in engineering workplaces, using interviews with a purposive sample of 13 students (4 male) recruited following a previous survey. Although the overall experience of workplace learning is positive for many students, male and female engineering students reported experiences consistent with masculine cultures. Educators and employers must proactively lead improvements to the culture in engineering workplaces, prepare students for gendered workplaces and support students to reflect during and after workplace experiences. The experiences presented here could be adapted to enhance inclusivity training.

  8. Demonstration Experiments with a Stirling Engine.

    Science.gov (United States)

    Deacon, Christopher G.; And Others

    1994-01-01

    Describes an investigation with the primary purpose of allowing students to generate and interpret a pressure/volume diagram of a Stirling engine. Explains how the Stirling engine can be used to demonstrate the principles of operation of a refrigerator and a heat pump. (DDR)

  9. National Educators' Workshop: Update 1991. Standard Experiments in Engineering Materials Science and Technology

    International Nuclear Information System (INIS)

    Gardner, J.E.; Jacobs, J.A.; Stiegler, J.O.

    1992-06-01

    Given here is a collection of experiments presented and demonstrated at the National Educators' Workshop: Update 91, held at the Oak Ridge National Laboratory on November 12-14, 1991. The experiments related to the nature and properties of engineering materials and provided information to assist in teaching about materials in the education community

  10. National Educators' Workshop: Update 1988. Standard Experiments in Engineering Materials Science and Technology

    Science.gov (United States)

    Gardner, James E. (Compiler); Jacobs, James A. (Compiler)

    1990-01-01

    Presented here is a collection of experiments presented and demonstrated at the National Educators' Workshop: Update 88, held May 10 to 12, 1988 at the National Institute of Standards and Technology (NIST), Gaithersberg, Maryland. The experiments related to the nature and properties of engineering materials and provided information to assist in teaching about materials in the education community.

  11. National Educators' Workshop: Update 1989 Standard Experiments in Engineering Materials Science and Technology

    Science.gov (United States)

    Gardner, James E. (Compiler); Jacobs, James A. (Compiler)

    1990-01-01

    Presented here is a collection of experiments presented and demonstrated at the National Educators' Workshop: Update 89, held October 17 to 19, 1989 at the National Aeronautics and Space Administration, Hampton, Virginia. The experiments related to the nature and properties of engineering materials and provided information to assist in teaching about materials in the education community.

  12. National Educators' Workshop: Update 95. Standard Experiments in Engineering Materials Science and Technology

    Science.gov (United States)

    Gardner, James E. (Compiler); Jacobs, James A.; Karnitz, Michael A.

    1996-01-01

    This document contains a collection of experiments presented and demonstrated at the National Educators' Workshop: Update 95. The experiments related to the nature and properties of engineering materials and provided information to assist in teaching about materials in the education community.

  13. National Educators' Workshop: Update 1993. Standard Experiments in Engineering Materials Science and Technology

    Science.gov (United States)

    Gardner, James E. (Compiler); Jacobs, James A. (Compiler)

    1994-01-01

    This document contains a collection of experiments presented and demonstrated at the National Educators' Workshop: Update 93 held at the NASA Langley Research Center in Hampton, Virginia, on November 3-5, 1993. The experiments related to the nature and properties of engineering materials and provided information to assist in teaching about materials in the education community.

  14. National Educators' Workshop: Update 1991. Standard Experiments in Engineering Materials Science and Technology

    Science.gov (United States)

    Gardner, James E. (Compiler); Jacobs, James A. (Compiler); Stiegler, James O. (Compiler)

    1992-01-01

    Given here is a collection of experiments presented and demonstrated at the National Educators' Workshop: Update 91, held at the Oak Ridge National Laboratory on November 12-14, 1991. The experiments related to the nature and properties of engineering materials and provided information to assist in teaching about materials in the education community.

  15. 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…

  16. Clinical Engineering: Experiences of assisted professional practices

    International Nuclear Information System (INIS)

    Langone, Luis; Vanetta, Marcos; Vazquez, Marcelo; Rotger, Viviana I; Olivera, Juan Manuel

    2007-01-01

    In the curricula of the Biomedical Engineering career of the Facultad de Ciencias Exactas y TecnologIa of the Universidad Nacional de Tucuman, Argenitna, there are the Assisted Professional Practices. Within this framework, the students have the possibility of performing practices in the clinic Sanatorio 9 de Julio. One of the objectives of these practices is to apply the concepts, methods and procedures studied along the career in the field work under real work conditions. From the point of view of the host institution, the objective is to improve the performance of the different services and areas applying the tools of Biomedical Engineering. The present work shows an example of such practices where an equipment preliminary analysis was made, its use and maintenance corresponding to the surgical unit of the clinic

  17. Sustainability in Design Engineering Education; Experiences in Northern Europe

    NARCIS (Netherlands)

    Dewulf, K.; Wever, R.; Boks, C.; Bakker, C.; D'hulster, F.

    2009-01-01

    In recent years, the implementation of sustainability into the curricula of engineering has become increasingly important. This paper focuses on the experiences of integrating sustainability in Design Engineering education in the academic bachelor programs at Delft University of Technology in The

  18. Women Engineering Transfer Students: The Community College Experience

    Science.gov (United States)

    Patterson, Susan J.

    2011-01-01

    An interpretative philosophical framework was applied to a case study to document the particular experiences and perspectives of ten women engineering transfer students who once attended a community college and are currently enrolled in one of two university professional engineering programs. This study is important because women still do not earn…

  19. Building a Framework for Engineering Design Experiences in High School

    Science.gov (United States)

    Denson, Cameron D.; Lammi, Matthew

    2014-01-01

    In this article, Denson and Lammi put forth a conceptual framework that will help promote the successful infusion of engineering design experiences into high school settings. When considering a conceptual framework of engineering design in high school settings, it is important to consider the complex issue at hand. For the purposes of this…

  20. Virtual parameter-estimation experiments in Bioprocess-Engineering education

    NARCIS (Netherlands)

    Sessink, O.D.T.; Beeftink, H.H.; Hartog, R.J.M.; Tramper, J.

    2006-01-01

    Cell growth kinetics and reactor concepts constitute essential knowledge for Bioprocess-Engineering students. Traditional learning of these concepts is supported by lectures, tutorials, and practicals: ICT offers opportunities for improvement. A virtual-experiment environment was developed that

  1. Software engineering experience from the LEP experiment OPAL

    International Nuclear Information System (INIS)

    Schaile, O.

    1990-01-01

    This contribution describes some of the activities within the OPAL collaboration at LEP to apply Software Engineering Techniques for program development and data documentation. It concentrates on two aspects: Structured Analysis Techniques and a data documentation system developed within OPAL. As far as evaluations are given they are the authors view and opinion

  2. Engineering Properties and Correlation Analysis of Fiber Cementitious Materials

    Directory of Open Access Journals (Sweden)

    Wei-Ting Lin

    2014-11-01

    Full Text Available This study focuses on the effect of the amount of silica fume addition and volume fraction of steel fiber on the engineering properties of cementitious materials. Test variables include dosage of silica fume (5% and 10%, water/cement ratio (0.35 and 0.55 and steel fiber dosage (0.5%, 1.0% and 2.0%. The experimental results included: compressive strength, direct tensile strength, splitting tensile strength, surface abrasion and drop-weight test, which were collected to carry out the analysis of variance to realize the relevancy and significance between material parameters and those mechanical properties. Test results illustrate that the splitting tensile strength, direct tensile strength, strain capacity and ability of crack-arresting increase with increasing steel fiber and silica fume dosages, as well as the optimum mixture of the fiber cementitious materials is 5% replacement silica fume and 2% fiber dosage. In addition, the Pearson correlation coefficient was conducted to evaluate the influence of the material variables and corresponds to the experiment result.

  3. Educational experiments of radiochemistry in the nuclear engineering school

    International Nuclear Information System (INIS)

    Akatsu, Eiko

    1995-06-01

    Educational experiments of radiochemistry are described. They were an improvement of educational experiment of burn-up measurement as well as experiments on a solvent extraction, a cation exchange behavior of 60 Co, liquid scintillation spectrometry and half-life determination of 87 Rb, and determination of 137 Cs in sea water. Two or one of the experiments were ordinarily studied, depending the occasional situations, by the students of the general course or of the nuclear engineering course in the Nuclear Engineering School, Nuclear Education Center, JAERI from 1976 to 1994. (author)

  4. Correlations of soil and rock properties in geotechnical engineering

    CERN Document Server

    Ameratunga, Jay; Das, Braja M

    2016-01-01

    This book presents a one-stop reference to the empirical correlations used extensively in geotechnical engineering. Empirical correlations play a key role in geotechnical engineering designs and analysis. Laboratory and in situ testing of soils can add significant cost to a civil engineering project. By using appropriate empirical correlations, it is possible to derive many design parameters, thus limiting our reliance on these soil tests. The authors have decades of experience in geotechnical engineering, as professional engineers or researchers. The objective of this book is to present a critical evaluation of a wide range of empirical correlations reported in the literature, along with typical values of soil parameters, in the light of their experience and knowledge. This book will be a one-stop-shop for the practising professionals, geotechnical researchers and academics looking for specific correlations for estimating certain geotechnical parameters. The empirical correlations in the forms of equations a...

  5. A Phenomenographic Investigation of the Ways Engineering Students Experience Innovation

    Science.gov (United States)

    Fila, Nicholas David

    Innovation has become an important phenomenon in engineering and engineering education. By developing novel, feasible, viable, and valued solutions to complex technical and human problems, engineers support the economic competitiveness of organizations, make a difference in the lives of users and other stakeholders, drive societal and scientific progress, and obtain key personal benefits. Innovation is also a complex phenomenon. It occurs across a variety of contexts and domains, encompasses numerous phases and activities, and requires unique competency profiles. Despite this complexity, many studies in engineering education focus on specific aspects (e.g., engineering students' abilities to generate original concepts during idea generation), and we still know little about the variety of ways engineering students approach and understand innovation. This study addresses that gap by asking: 1. What are the qualitatively different ways engineering students experience innovation during their engineering projects? 2. What are the structural relationships between the ways engineering students experience innovation? This study utilized phenomenography, a qualitative research method, to explore the above research questions. Thirty-three engineering students were recruited to ensure thorough coverage along four factors suggested by the literature to support differences related to innovation: engineering project experience, academic major, year in school, and gender. Each participant completed a 1-2 hour, semi-structured interview that focused on experiences with and conceptions of innovation. Whole transcripts were analyzed using an eight-stage, iterative, and comparative approach meant to identify a limited number of categories of description (composite ways of experiencing innovation comprised of the experiences of several participants), and the structural relationships between these categories. Phenomenographic analysis revealed eight categories of description that were

  6. Engineering teacher training models and experiences

    Science.gov (United States)

    González-Tirados, R. M.

    2009-04-01

    Institutions and Organisations that take training seriously and devote time, effort and resources, etc, to their own teams are more likely to succeed, since both initial teacher training and continuous improvement, studies, hours of group discussion, works on innovation and educational research, talks and permanent meetings, etc, will all serve to enhance teaching and its quality. Teachers will be able to introduce new components from previously taught classes into their university teaching which will contribute to improving their work and developing a suitable academic environment to include shared objectives, teachers and students. Moreover, this training will serve to enhance pedagogic innovation, new teaching-learning methodologies and contribute to getting teaching staff involved in respect of the guidelines set out by the EHEA. Bearing in mind that training and motivation can be key factors in any teacher's "performance", their productivity and the quality of their teaching, Teacher Training for a specific post inside the University Organisation is standard practice of so-called Human Resources management and an integral part of a teacher's work; it is a way of professionalising the teaching of the different branches of Engineering. At Madrid Polytechnic University, in the Institute of Educational Sciences (ICE), since it was founded in 1972, we have been working hard with university teaching staff. But it was not until 1992 after carrying out various studies on training needs that we planned and programmed different training actions, offering a wide range of possibilities. Thus, we designed and taught an "Initial Teacher Training Course", as it was first called in 1992, a programme basically aimed to train young Engineering teachers just setting out on their teaching career. In 2006, the name was changed to "Advanced University Teacher Training Course". Subsequently, with the appearance of the Bologna Declaration and the creation of the European Higher

  7. Hybrid rocket engine, theoretical model and experiment

    Science.gov (United States)

    Chelaru, Teodor-Viorel; Mingireanu, Florin

    2011-06-01

    The purpose of this paper is to build a theoretical model for the hybrid rocket engine/motor and to validate it using experimental results. The work approaches the main problems of the hybrid motor: the scalability, the stability/controllability of the operating parameters and the increasing of the solid fuel regression rate. At first, we focus on theoretical models for hybrid rocket motor and compare the results with already available experimental data from various research groups. A primary computation model is presented together with results from a numerical algorithm based on a computational model. We present theoretical predictions for several commercial hybrid rocket motors, having different scales and compare them with experimental measurements of those hybrid rocket motors. Next the paper focuses on tribrid rocket motor concept, which by supplementary liquid fuel injection can improve the thrust controllability. A complementary computation model is also presented to estimate regression rate increase of solid fuel doped with oxidizer. Finally, the stability of the hybrid rocket motor is investigated using Liapunov theory. Stability coefficients obtained are dependent on burning parameters while the stability and command matrixes are identified. The paper presents thoroughly the input data of the model, which ensures the reproducibility of the numerical results by independent researchers.

  8. Optical engineering: understanding optical system by experiments

    Science.gov (United States)

    Scharf, Toralf

    2017-08-01

    Students have to be educated in theoretical and practical matters. Only one of them does not allow attacking complex problems in research, development, and management. After their study, students should be able to design, construct and analyze technical problems at highest levels of complexity. Who never experienced the difficulty of setting up measurements will not be able to understand, plan and manage such complex tasks in her/his future career. At EPFL a course was developed for bachelor education and is based on three pillars: concrete actions (enactive) to be done by the students, a synthesis of their work by writing a report (considered as the iconic part) and inputs from the teacher to generalize the findings and link it to a possible complete abstract description (symbolic). Intensive tutoring allowed an intermodal transfer between these categories. This EIS method originally introduced by Jerome Bruner for small children is particular well adapted for engineer education for which theoretical understanding often is not enough. The symbiosis of ex-cathedra lecture and practical work in a classroom-like situation presents an innovative step towards integrated learning that complements perfectly more abstract course principles like online courses.

  9. Engineering properties of nuclear waste slurries - 16378

    International Nuclear Information System (INIS)

    Biggs, Simon; Fairweather, Michael; Hunter, Timothy; Omokanye, Qanitalillahi; Peakall, Jeffrey

    2009-01-01

    The type of particulate systems encountered in legacy nuclear waste slurries is highly complicated, with the aggregation and flow behaviour being at times very variable. However, deconstructing the complex overall slurry activity to singular particle-particle interactions can lead to a greater understanding of the mechanisms involved with particle aggregation, and so to predictions of their settling and flow in nuclear systems. Of particular importance to legacy waste is the role of salts in controlling the attraction of particles (and so in dictating the rheological properties of the system) as sludge may contain a variety of specific ions and generally have high ionic conductivity [1]. In this paper, particle-particle interactions are characterised using a number of complimentary methods, and their influence on resulting flow and bed compression is measured. The methods used to characterise the particle-particle interactions under various salt and pH conditions were electro-acoustic analysis (zeta potential) and atomic force microscopy (AFM). Following on from the analysis of particle-particle properties, bulk sediment behaviour was investigated using shear and compressive yield stress measurements, vital parameters in dictating flow and dewatering performance, respectively. Together, these techniques enable the characterisation of a range of particulate systems that may be encountered in legacy wastes, and results point to a number of important factors that can help explain the observed variability in industrial slurry behaviour. (authors)

  10. Summary of results of underground engineering experience

    Energy Technology Data Exchange (ETDEWEB)

    Holzer, F [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

    1969-07-01

    Results pertinent to the use of nuclear explosives in underground engineering applications have been accumulating for the past 10 years from the Plowshare and Weapons tests of the AEC. Thus, predictive and measurement techniques of shock effects and chimney formation were developed in the course of analyzing explosions in granite, salt, and dolomite. The ability to predict effects related specifically to safety has resulted from many measurements on detonations at the Nevada Test Site, where also many of the techniques for handling, emplacing, and firing the explosive have been developed. This gestation period culminated in the execution of Project Gasbuggy, jointly sponsored by industry and government, and the first nuclear explosion in a gasbearing formation. The Gasbuggy explosive had a nominal yield of 25 kt and was detonated 4240 ft below the surface in the San Juan Basin in northwestern New Mexico on December 10, 1967. The shot point was 40 ft below the lower boundary of a 285-ft-thick gas-bearing sandstone formation of very low permeability. No radioactive venting occurred, and no damage to surrounding gas wells or structures resulted. Post-shot geophysical exploration and gas production tests have revealed that the nuclear explosion created a subsurface chimney approximately 160 ft in diameter and 335 ft high. Fractures appear to extend to about 400 ft symmetrically from the detonation point, with shifts or offsets along geological weaknesses extending out to perhaps 750 ft. Presently, radioactive constituents in the gas consist of tritium and krypton-85, with concentrations of approximately 10 {mu}Ci/ft{sup 3} and 1.5 {mu}Ci/ft{sup 3} respectively. These concentrations are decreasing a gas withdrawn from the chimney is replaced by formation gas. Tests to evaluate the increase in productivity and ultimate recovery are currently in progress. (author)

  11. Summary of results of underground engineering experience

    International Nuclear Information System (INIS)

    Holzer, F.

    1969-01-01

    Results pertinent to the use of nuclear explosives in underground engineering applications have been accumulating for the past 10 years from the Plowshare and Weapons tests of the AEC. Thus, predictive and measurement techniques of shock effects and chimney formation were developed in the course of analyzing explosions in granite, salt, and dolomite. The ability to predict effects related specifically to safety has resulted from many measurements on detonations at the Nevada Test Site, where also many of the techniques for handling, emplacing, and firing the explosive have been developed. This gestation period culminated in the execution of Project Gasbuggy, jointly sponsored by industry and government, and the first nuclear explosion in a gasbearing formation. The Gasbuggy explosive had a nominal yield of 25 kt and was detonated 4240 ft below the surface in the San Juan Basin in northwestern New Mexico on December 10, 1967. The shot point was 40 ft below the lower boundary of a 285-ft-thick gas-bearing sandstone formation of very low permeability. No radioactive venting occurred, and no damage to surrounding gas wells or structures resulted. Post-shot geophysical exploration and gas production tests have revealed that the nuclear explosion created a subsurface chimney approximately 160 ft in diameter and 335 ft high. Fractures appear to extend to about 400 ft symmetrically from the detonation point, with shifts or offsets along geological weaknesses extending out to perhaps 750 ft. Presently, radioactive constituents in the gas consist of tritium and krypton-85, with concentrations of approximately 10 μCi/ft 3 and 1.5 μCi/ft 3 respectively. These concentrations are decreasing a gas withdrawn from the chimney is replaced by formation gas. Tests to evaluate the increase in productivity and ultimate recovery are currently in progress. (author)

  12. Research on the NPP human factors engineering operating experience review

    International Nuclear Information System (INIS)

    Ren Xiangchen; Miao Hongxing; Ning Zhonghe

    2006-01-01

    This paper addresses the importance of the human factors engineering (HFE) for the design of nuclear power plant (NPP), especially for the design of human-machine interface in the NPP. It also summarizes the scope and content of the NPP HFE. The function, scope, content and process of the NPP human factors engineering operating experience review (OER) are mainly focused on, and significantly discussed. Finally, it briefly introduces the situation of the studies on the OER in China. (authors)

  13. Educational laboratory experiments on chemistry in a nuclear engineering school

    International Nuclear Information System (INIS)

    Akatsu, E.

    1982-01-01

    An educational laboratory experiment on radiochemistry was investigated by students in the general course of the Nuclear Engineering School of Japan Atomic Energy Research Institute. Most of them are not chemical engineers, but electrical and mechanical engineers. Therefore, the educational experiment was designed for them by introducing a ''word experiment'' in the initial stage and by reducing the chemical procedure as far as possible. It began with calculations on a simple solvent extraction process-the ''word experiment''--followed by the chemical separation of 144 Pr from 144 Ce with tri-n-butyl phosphate in a nitric acid system and then measurement of the radioactive decay and growth of the separated 144 Pr and 144 Ce, respectively. The chemical procedure was explained by the phenomenon but not by the mechanism of chelation. Most students thought the experiment was an exercise in solvent extraction or radiochemical separation rather than a radioactive equilibrium experiment. However, a pure chemist considered it as a sort of physical experiment, where the chemical procedure was used only for preparation of measuring samples. Another experiment, where 137 Cs was measured after isolation with ammonium phosphomolybdate, was also investigated. The experiment eliminated the need for students who were not chemists to know how to use radioactive tracers. These students appreciated the realization that they could understand the radioactivity in the environmental samples in a chemical frame of reference even though they were not chemists

  14. Mechanical Properties Experimental Study of Engineering Vehicle Refurbished Tire

    Science.gov (United States)

    Qiang, Wang; Xiaojie, Qi; Zhao, Yang; Yunlong, Wang; Guotian, Wang; Degang, Lv

    2018-05-01

    The vehicle refurbished tire test system was constructed, got load-deformation, load-stiffness, and load-compression ratio property laws of engineering vehicle refurbished tire under the working condition of static state and ground contact, and built radial direction loading deformation mathematics model of 26.5R25 engineering vehicle refurbished tire. The test results show that radial-direction and side-direction deformation value is a little less than that of the new tire. The radial-direction stiffness and compression ratio of engineering vehicle refurbished tire were greatly influenced by radial-direction load and air inflation pressure. When load was certain, radial-direction stiffness would increase with air inflation pressure increasing. When air inflation pressure was certain, compression ratio of engineering vehicle refurbished tire would enlarge with radial-direction load increasing, which was a little less than that of the new and the same type tire. Aging degree of old car-case would exert a great influence on deformation property of engineering vehicle refurbished tire, thus engineering vehicle refurbished tires are suitable to the working condition of low tire pressure and less load.

  15. Improvement of engineering soil properties using non -traditional additives

    Directory of Open Access Journals (Sweden)

    Waheed Mohanned

    2018-01-01

    Full Text Available Laboratory experiments are conducted to evaluate the effect of some non-traditional additives on the engineering properties of clayey soil, which show problematic phenomenon when used as a construction material. The conducted tests covered the influence of these additives on various parameters like consistency limits, compaction characteristics and CBR value. Two nontraditional stabilizers are selected in this study, polymers and phosphoric acid at three different percent which are (1%, 3% and 5% of the dry soil weight. It is concluded that addition of the polymer to the clayey soil results in a slight increase in plastic limit while the liquid limit is not affected accompanied by a marginal decrease in the dry unit weight while the optimum moisture content remains unaffected. The addition of phosphoric acid to the clayey soil has no effect on its Atterberg limits. In general, it is observed that polymer is found to be ineffective as a stabilizer to improve clayey soils, especially in small amounts of about (3%. The phosphoric acid treated soil gained better improvement for all amounts of additive used. For (3% acid treated soil the CBR is about (360% compared to that of untreated soil, for that, it can be concluded that the improvement using phosphoric acid in the clay soils is a promising option and can be applied to solve the geotechnical stabilization problems.

  16. Experience in education and training of gas engineers in Russia

    International Nuclear Information System (INIS)

    Basniev, K.; Vladimirov, A.

    1997-01-01

    Experience gained in training and retraining of engineers for gas industry is considered in the report. The report contains the material on modern state of higher technical education in Russia in view of the reforms taking place in this country. The report deals with questions concerning the experience gained in a specialized training of gas engineers at higher educational establishments of Russia including training of specialists for foreign countries. Conditions under which retraining of engineers involved in gas industry takes place are presented in the report. The report is based mainly on the experience gained by the Russian leading higher educational establishment of oil and gas profile, that is the State Gubkin Oil and Gas Academy. (au)

  17. Some engineering properties of shelled and kernel tea ( Camellia ...

    African Journals Online (AJOL)

    Some engineering properties (size dimensions, sphericity, volume, bulk and true densities, friction coefficient, colour characteristics and mechanical behaviour as rupture ... The static coefficients of friction of shelled and kernel tea seeds for the large and small sizes higher values for rubber than the other friction surfaces.

  18. Proposed Average Values of Some Engineering Properties of Palm ...

    African Journals Online (AJOL)

    The need to know what values of engineering properties of palm kernels to use for rational design of handling and processing systems for palm kernels prompted a literature search for collation of published values. These values are presented in this work. And to manage the discrepancies observed among values published ...

  19. Plasma engineering assessments of compact ignition experiments

    International Nuclear Information System (INIS)

    Houlberg, W.A.

    1985-01-01

    Confinement, startup sequences, and fast-alpha particle effects are assessed for a class of compact tokamak ignition experiments having high toroidal magnetic fields (8 to 12 T) and high toroidal currents (7 to 10 MA). The uncertainties in confinement scaling are spanned through examples of performance with an optimistic model based on ohmically heated plasmas and a pessimistic model that includes confinement degradation by both auxiliary and alpha heating. The roles of neoclassical resistivity enhancement and sawtooth behavior are also evaluated. Copper toroidal field coils place restrictions on pulse lengths due to resistive heating, so a simultaneous rampup of the toroidal field and plasma current is proposed as a means of compressing the startup phase and lengthening the burn phase. If the ignition window is small, fast-alpha particle physics is restricted to the high-density regime where a short slowing-down time leads to low fast-particle density and pressure contributions. Under more optimistic confinement, a larger ignition margin broadens the range of alpha particle physics that can be addressed. These issues are illustrated through examples of transport simulations for a set of machine parameters called BRAND-X, which typify the designs under study

  20. Plasma engineering assessments of compact ignition experiments

    International Nuclear Information System (INIS)

    Houlberg, W.A.

    1986-01-01

    Confinement, startup sequences, and fast-alpha particle effects are assessed for a class of compact tokamak ignition experiments having high toroidal magnetic fields (8-12 T) and high toroidal currents (7-10 MA). The uncertainties in confinement scaling are spanned through examples of performance with an optimistic model based on ohmically heated plasmas and a pessimistic model that includes confinement degradation by both auxiliary and alpha heating. The roles of neoclassical resistivity enhancement and sawtooth behavior are also evaluated. Copper toroidal field coils place restrictions on pulse lengths due to resistive heating, so a simultaneous rampup of the toroidal field and plasma current is proposed as a means of compressing the startup phase and lengthening the burn phase. If the ignition window is small, fast-alpha particle physics is restricted to the high-density regime where a short slowing-down time leads to low fast-particle density and pressure contributions. Under more optimistic confinement, a larger ignition margin broadens the range of alpha particle physics that can be addressed. These issues are illustrated through examples of transport simulations for a set of machine parameters called BRAND-X, which typify the designs under study

  1. Managing reality shock: Expectations versus experiences of graduate engineers

    Directory of Open Access Journals (Sweden)

    Sarah Riordan

    2007-10-01

    Full Text Available The objective of the study is an analysis of the relationship between the work expectations and experiences of graduate engineers during their early career period. It reports on discrepancies in graduates’ expectations of the world of work and the reality of the early career stage. Conclusions include recommendations of how "reality shock" can be managed better by both organisations and individuals. Qualitative data were obtained through in-depth interviews with sixteen participants with less than five years work experience, employed in a large utility organisation in the Western Cape. Results indicate that participants experience significant incongruence between their expectations of work and work experiences.

  2. Project-Based Laboratory Experiences in Mechanical Engineering

    Directory of Open Access Journals (Sweden)

    Narendra Sharma

    2011-12-01

    Full Text Available In this paper we describe project-based laboratories in Mechanical Engineering designed to provide semester-long team experiences which mimic the real life industrial processes of design, development, testing and optimization. The labs are focused on courses at the sophomore level and thus require special attention to constraints of student backgrounds and experience. This paper describes laboratory projects in Dynamics and Fluid Mechanics.

  3. Women's Experiences in the Engineering Laboratory in Japan

    Science.gov (United States)

    Hosaka, Masako

    2014-01-01

    This qualitative study aims to examine Japanese women undergraduate engineering students' experiences of interacting with departmental peers of the same year in the laboratory setting by using interview data of 32 final-year students at two modestly selective national universities in Japan. Expectation state theory that explains unequal…

  4. Learning English: Experiences and Needs of Saudi Engineering Students

    Science.gov (United States)

    Unruh, Susan; Obeidat, Fayiz

    2015-01-01

    In this qualitative study, Saudi engineering students talk openly of their experiences learning English in the Kingdom of Saudi Arabia (KSA) and as university students in the United States (US). These students reported that they learned only the basics of vocabulary and grammar in KSA. Consequently, they came to the US with few English skills. In…

  5. Engineered barrier experiment. Power control and data acquisition systems

    International Nuclear Information System (INIS)

    Alberdi, J.; Barcala, J.M.; Gamero, E.; Martin, P.L.; Molinero, A.; Navarrete, J.J.; Yuste, C.

    1997-01-01

    The engineered barrier concept for the storage of radioactive wastes is being tested at almost full scale at CIEMAT facilities. A data acquisition and control is an element of this experiment. This system would be operating for next three years. (Author)

  6. Creating meaningful learning experiences: Understanding students' perspectives of engineering design

    Science.gov (United States)

    Aleong, Richard James Chung Mun

    , relevance, and transfer. With this framework of student learning, engineering educators can enhance learning experiences by engaging all three levels of students' understanding. The curriculum studies orientation applied the three holistic elements of curriculum---subject matter, society, and the individual---to conceptualize design considerations for engineering curriculum and teaching practice. This research supports the characterization of students' learning experiences to help educators and students optimize their teaching and learning of design education.

  7. A practitioner’s experiences operationalizing Resilience Engineering

    International Nuclear Information System (INIS)

    Lay, E.; Branlat, M.; Woods, Z.

    2015-01-01

    Resilience Engineering (RE) is a reframed perspective. This begs the question, “How to operationalize a shift in perspective?” We share strategies, tactics, experiences, and observations from implementing Resilience Engineering in power generation equipment maintenance. Use of Resilience Engineering principles shifts focus to the future, to systems, and to how people really work (not the idealized version of work). We more effectively shape outcomes as we pay attention to what’s coming, looking for signs we’re outside normal work or running out of margins that enable us to adapt and respond. Use of these principles opens new possibilities grounded in theoretical fields of biology, cognitive and system sciences (understand Cartesian views of the world work well for machines but not for people) and underlain by core principles (e.g., people fundamentally want to do a good job, actions taken make sense at the time, and system factors are tremendously influential on outcomes). This paper presents a practitioner’s account of a Resilience Engineering approach in the context of power plant maintenance. The paper will describe how the introduction of RE principles was made possible through supporting/fostering shifts in perspective and gaining buy-in at various levels of the organization. - Highlights: • Resilience Engineering is a shifted perspective as compared to a new program. • RE is grounded in fields of biology, cognitive and system sciences. • We share strategies, tactics, experiences, and observations for implementing RE. • We used a middle out approach

  8. First experiments results about the engineering model of Rapsodie

    International Nuclear Information System (INIS)

    Chalot, A.; Ginier, R.; Sauvage, M.

    1964-01-01

    This report deals with the first series of experiments carried out on the engineering model of Rapsodie and on an associated sodium facility set in a laboratory hall of Cadarache. It conveys more precisely: 1/ - The difficulties encountered during the erection and assembly of the engineering model and a compilation of the results of the first series of experiments and tests carried out on this installation (loading of the subassemblies preheating, thermal chocks...). 2/ - The experiments and tests carried out on the two prototypes control rod drive mechanisms which brought to the choice for the design of the definitive drive mechanism. As a whole, the results proved the validity of the general design principles adopted for Rapsodie. (authors) [fr

  9. Experiments in Creative Engineering at the Department of Mechanical Engineering in Kurume National College of Technology

    Science.gov (United States)

    Tanaka, Hiroshi; Hashimura, Shinji; Hiroo, Yasuaki

    We present a program to learn ability to solve problems on engineering. This program is called “Experiments in creative engineering” in the department of mechanical engineering in Kurume National College of Technology advanced engineering school. In the program, students have to determine own theme and manufacture experimental devices or some machines by themselves. The students must also perform experiments to valid the function and performance of their devices by themselves. The restriction of the theme is to manufacture a device which function dose not basically exist in the world with limited cost (up to 20,000Yen) . As the results of questionnaire of students, the program would be very effective to the creative education for the students.

  10. Business oriented educational experiments enhance active learning by engineering students

    DEFF Research Database (Denmark)

    Christiansen, Nynne Mia; Schjær-Jacobsen, Hans; Simon, Jens

    2012-01-01

    It is generally agreed that one of the keys to recreating industrial growth after the financial crisis is to mobilize universities and engineering schools to be more actively involved in innovation and entrepreneurship activities in cooperation with industrial companies. This active learning...... exploration symposium on bridging the gap between engineering education and business is proposed on the basis of the Copenhagen University College of Engineering (IHK) being involved in a DKK 50m ongoing project “Business Oriented Educational Experiments” financed by the Capital Region of Denmark...... and the European Social Fund. The project is carried out with other major educational institutions in the Copenhagen area and organized in five themes: 1) world class competences, 2) new interactions between education and business, 3) the experimenting organization, 4) education on demand, and 5) new career paths...

  11. Apollo experience report: Guidance and control systems. Engineering simulation program

    Science.gov (United States)

    Gilbert, D. W.

    1973-01-01

    The Apollo Program experience from early 1962 to July 1969 with respect to the engineering-simulation support and the problems encountered is summarized in this report. Engineering simulation in support of the Apollo guidance and control system is discussed in terms of design analysis and verification, certification of hardware in closed-loop operation, verification of hardware/software compatibility, and verification of both software and procedures for each mission. The magnitude, time, and cost of the engineering simulations are described with respect to hardware availability, NASA and contractor facilities (for verification of the command module, the lunar module, and the primary guidance, navigation, and control system), and scheduling and planning considerations. Recommendations are made regarding implementation of similar, large-scale simulations for future programs.

  12. High temperature engineering research facilities and experiments in China

    International Nuclear Information System (INIS)

    Xu, Yuanhui; Liu, Meisheng; Yao, Huizhong; Ju, Huaiming

    1998-01-01

    June 14, 1995, the construction of a pebble bed type high temperature gas-cooled reactor (HTGR) started in China. It is a test reactor with 10 MW thermal power output (termed HTR- 10). The test reactor is located on the site of Institute of Nuclear Energy Technology (INET) of Tsinghua University in the northwest suburb of Beijing, about 40 km away from the city. Design of the HTR-10 test reactor represents the features of HTR-Modular design: 'side-by-side' arrangement, spherical fuel elements with 'multi-pass' loading scheme, completely passive decay heat removal, reactor shutdown systems in the side reflector, etc. However, in the HTR-10 design some modifications from the HTR-Module were made to satisfy Chinese conditions. For example, the steam generator is composed of a number of modular helical tubes with small diameter, pulse pneumatic discharging apparatus are used in the fuel handling system and step motor driving control rods are designed. These modifications would cause some uncertainty in our design. It is necessary to do engineering experiments to prove these new or modified ideas. Therefore, a program of engineering experiments for HTR-10 key technologies is being conducted at INET. The main aims of these engineering experiments are to verify the designed characteristics and performance of the components and systems, to feedback on design and to obtain operational experiences. Those engineering experiments are depressurization test of the hot gas duct at room temperature and operating pressure, performance test of the hot gas duct at operating helium temperature and pressure, performance test of the pulse pneumatic fuel handling system, test of the control rods driving apparatus, two phase flow stability test for the once through steam generator and cross mixture test at the bottom of the reactor core

  13. Engineering properties for high kitchen waste content municipal solid waste

    Directory of Open Access Journals (Sweden)

    Wu Gao

    2015-12-01

    Full Text Available Engineering properties of municipal solid waste (MSW depend largely on the waste's initial composition and degree of degradation. MSWs in developing countries usually have a high kitchen waste content (called HKWC MSW. After comparing and analyzing the laboratory and field test results of physical composition, hydraulic properties, gas generation and gas permeability, and mechanical properties for HKWC MSW and low kitchen waste content MSW (called LKWC MSW, the following findings were obtained: (1 HKWC MSW has a higher initial water content (IWC than LKWC MSW, but the field capacities of decomposed HKWC and LKWC MSWs are similar; (2 the hydraulic conductivity and gas permeability for HKWC MSW are both an order of magnitude smaller than those for LKWC MSW; (3 compared with LKWC MSW, HKWC MSW has a higher landfill gas (LFG generation rate but a shorter duration and a lower potential capacity; (4 the primary compression feature for decomposed HKWC MSW is similar to that of decomposed LKWC MSW, but the compression induced by degradation of HKWC MSW is greater than that of LKWC MSW; and (5 the shear strength of HKWC MSW changes significantly with time and strain. Based on the differences of engineering properties between these two kinds of MSWs, the geo-environmental issues in HKWC MSW landfills were analyzed, including high leachate production, high leachate mounds, low LFG collection efficiency, large settlement and slope stability problem, and corresponding advice for the management and design of HKWC MSW landfills was recommended.

  14. Selected engineering properties and applications of EPS geofoam

    Science.gov (United States)

    Elragi, Ahmed Fouad

    Expanded polystyrene (EPS) geofoam is a lightweight material that has been used in engineering applications since at least the 1950s. Its density is about a hundredth of that of soil. It has good thermal insulation properties with stiffness and compression strength comparable to medium clay. It is utilized in reducing settlement below embankments, sound and vibration damping, reducing lateral pressure on substructures, reducing stresses on rigid buried conduits and related applications. This study starts with an overview on EPS geofoam. EPS manufacturing processes are described followed by a review of engineering properties found in previous research work done so far. Standards and design manuals applicable to EPS are presented. Selected EPS geofoam-engineering applications are discussed with examples. State-of-the-art of experimental work is done on different sizes of EPS specimens under different loading rates for better understanding of the behavior of the material. The effects of creep, sample size, strain rate and cyclic loading on the stress strain response are studied. Equations for the initial modulus and the strength of the material under compression for different strain rates are presented. The initial modulus and Poisson's ratio are discussed in detail. Sample size effect on creep behavior is examined. Three EPS projects are shown in this study. The creep behavior of the largest EPS geofoam embankment fill is shown. Results from laboratory tests, mathematical modeling and field records are compared to each other. Field records of a geofoam-stabilized slope are compared to finite difference analysis results. Lateral stress reduction on an EPS backfill retaining structure is analyzed. The study ends with a discussion on two promising properties of EPS geofoam. These are the damping ability and the compressibility of this material. Finite element analysis, finite difference analysis and lab results are included in this discussion. The discussion with the

  15. 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

  16. Analysis of BJ493 diesel engine lubrication system properties

    Science.gov (United States)

    Liu, F.

    2017-12-01

    The BJ493ZLQ4A diesel engine design is based on the primary model of BJ493ZLQ3, of which exhaust level is upgraded to the National GB5 standard due to the improved design of combustion and injection systems. Given the above changes in the diesel lubrication system, its improved properties are analyzed in this paper. According to the structures, technical parameters and indices of the lubrication system, the lubrication system model of BJ493ZLQ4A diesel engine was constructed using the Flowmaster flow simulation software. The properties of the diesel engine lubrication system, such as the oil flow rate and pressure at different rotational speeds were analyzed for the schemes involving large- and small-scale oil filters. The calculated values of the main oil channel pressure are in good agreement with the experimental results, which verifies the proposed model feasibility. The calculation results show that the main oil channel pressure and maximum oil flow rate values for the large-scale oil filter scheme satisfy the design requirements, while the small-scale scheme yields too low main oil channel’s pressure and too high. Therefore, application of small-scale oil filters is hazardous, and the large-scale scheme is recommended.

  17. Engineering Physics Division integral experiments and their analyses

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    Integral experiments are performed as part of the Engineering Physics Division's on-going research in the development and application of radiation shielding methods. Integral experiments performed at the Oak Ridge Electron Linear Accelerator (ORELA) under the Division's Magnetic Fusion program are designed to provide data against which ORNL and all other organizations involved in shielding calculations for fusion devices can test their calculational methods and interaction data. The Tower Shielding Facility (TSF) continues to be the primary source of integral data for fission reactor shielding design. The experiments performed at the TSF during the last few years have been sponsored by the Gas Cooled Fast Reactor (GCFR) program. During this report period final documentation was also prepared for the remaining LMFBR shielding experiments, including an examination of streaming through annular slits and measurement of secondary gamma-ray production in reinforced concrete

  18. Engineering the mechanical and biological properties of nanofibrous vascular grafts for in situ vascular tissue engineering.

    Science.gov (United States)

    Henry, Jeffrey J D; Yu, Jian; Wang, Aijun; Lee, Randall; Fang, Jun; Li, Song

    2017-08-17

    Synthetic small diameter vascular grafts have a high failure rate, and endothelialization is critical for preventing thrombosis and graft occlusion. A promising approach is in situ tissue engineering, whereby an acellular scaffold is implanted and provides stimulatory cues to guide the in situ remodeling into a functional blood vessel. An ideal scaffold should have sufficient binding sites for biomolecule immobilization and a mechanical property similar to native tissue. Here we developed a novel method to blend low molecular weight (LMW) elastic polymer during electrospinning process to increase conjugation sites and to improve the mechanical property of vascular grafts. LMW elastic polymer improved the elasticity of the scaffolds, and significantly increased the amount of heparin conjugated to the micro/nanofibrous scaffolds, which in turn increased the loading capacity of vascular endothelial growth factor (VEGF) and prolonged the release of VEGF. Vascular grafts were implanted into the carotid artery of rats to evaluate the in vivo performance. VEGF treatment significantly enhanced endothelium formation and the overall patency of vascular grafts. Heparin coating also increased cell infiltration into the electrospun grafts, thus increasing the production of collagen and elastin within the graft wall. This work demonstrates that LMW elastic polymer blending is an approach to engineer the mechanical and biological property of micro/nanofibrous vascular grafts for in situ vascular tissue engineering.

  19. Experiments on Plume Spreading by Engineered Injection and Extraction

    Science.gov (United States)

    Mays, D. C.; Jones, M.; Tigera, R. G.; Neupauer, R.

    2014-12-01

    The notion that groundwater remediation is transport-limited emphasizes the coupling between physical (i.e., hydrodynamic), geochemical, and microbiological processes in the subsurface. Here we leverage this coupling to promote groundwater remediation using the approach of engineered injection and extraction. In this approach, inspired by the literature on chaotic advection, uncontaminated groundwater is injected and extracted through a manifold of wells surrounding the contaminated plume. The potential of this approach lies in its ability to actively manipulate the velocity field near the contaminated plume, generating plume spreading above and beyond that resulting from aquifer heterogeneity. Plume spreading, in turn, promotes mixing and reaction by chemical and biological processes. Simulations have predicted that engineered injection and extraction generates (1) chaotic advection whose characteristics depend on aquifer heterogeneity, and (2) faster rates and increased extent of groundwater remediation. This presentation focuses on a complimentary effort to experimentally demonstrate these predictions experimentally. In preparation for future work using refractive index matched (RIM) porous media, the experiments reported here use a Hele-Shaw apparatus containing silicone oil. Engineered injection and extraction is used to manipulate the geometry of an initially circular plume of black pigment, and photographs record the plume geometry after each step of injection of extraction. Image analysis, using complimentary Eulerian and Lagrangian approaches, reveals the thickness and variability of the dispersion zone surrounding the deformed plume of black pigment. The size, shape, and evolution of this dispersion zone provides insight into the interplay between engineered injection and extraction, which generates plume structure, and dispersion (here Taylor dispersion), which destroys plume structure. These experiments lay the groundwork for application of engineered

  20. Engineering education for youth: Diverse elementary school students' experiences with engineering design

    Science.gov (United States)

    Hegedus, Theresa

    Lingering concerns over the persistent achievement gap amidst the trend of an increasingly diverse society have been compounded by calls from the Oval Office, the National Science Board, and nationwide media to also address our current creativity crisis. Now, more than ever, we have a responsibility to produce a STEM-capable (science, technology, engineering, and mathematics) workforce to meet the demands of our rapidly changing local and global economic landscape. Barriers exist in our traditional educational system, which has historically limited underrepresented groups' affiliation and membership in the disciplines of science and engineering. The recent incorporation of engineering into the latest science education reform efforts presents an opportunity to expose students as early as elementary school to engineering practices and habits of mind, which have the potential to stimulate creative thinking skills through engineering design. This qualitative study was designed to examine the ways in which engineering education has the potential to promote creativity and academic competence in elementary science classrooms. As a part of my study, a diverse group of students from two fifth-grade classrooms took part in a 10-12 hour, engineering-based curriculum unit (Engineering is Elementary) during their regular science instructional time. Using a sociocultural lens, to include cultural production and identities in practice as part of my framework, I analyzed group and individual performances through classroom observations, student interviews, and teacher reflections to better understand the meaning students made of their experiences with engineering. Findings from the study included the ways in which creativity was culturally produced in the classroom to include: 1) idea generation; 2) design and innovation; 3) gumption/resourcefulness; and 4) social value. Opportunities for collaboration increased through each stage of the unit culminating with the design challenge

  1. Collaboration for cooperative work experience programs in biomedical engineering education.

    Science.gov (United States)

    Krishnan, Shankar

    2010-01-01

    Incorporating cooperative education modules as a segment of the undergraduate educational program is aimed to assist students in gaining real-life experience in the field of their choice. The cooperative work modules facilitate the students in exploring different realistic aspects of work processes in the field. The track records for cooperative learning modules are very positive. However, it is indeed a challenge for the faculty developing Biomedical Engineering (BME) curriculum to include cooperative work experience or internship requirements coupled with a heavy course load through the entire program. The objective of the present work is to develop a scheme for collaborative co-op work experience for the undergraduate training in the fast-growing BME programs. A few co-op/internship models are developed for the students pursuing undergraduate BME degree. The salient features of one co-op model are described. The results obtained support the proposed scheme. In conclusion, the cooperative work experience will be an invaluable segment in biomedical engineering education and an appropriate model has to be selected to blend with the overall training program.

  2. Some engineering properties of heavy concrete added silica fume

    International Nuclear Information System (INIS)

    Akkaş, Ayşe; Başyiğit, Celalettin; Esen, Serap

    2013-01-01

    Many different types of building materials have been used in building construction for years. Heavy concretes can be used as a building material for critical building as it can contain a mixture of many heavy elements. The barite itself for radiation shielding can be used and also in concrete to produce the workable concrete with a maximum density and adequate structural strength. In this study, some engineering properties like compressive strength, elasticity modules and flexure strength of heavy concretes’ added Silica fume have been investigated

  3. Engineering aspects of the Stanford relativity gyro experiment

    Science.gov (United States)

    Everitt, C. W. F.; Debra, D. B.

    1981-01-01

    According to certain theoretical predictions, the Newtonian laws of motion must be corrected for the effect of a gravitational field. Schiff (1960) proposed an experiment which would demonstrate the effect predicted by Einstein's Theory of General Relativity on a gyroscope. The experiment has been under development at Stanford University since 1961. The requirements involved make it necessary that the test be performed in a satellite to take advantage of weightlessness in space. In a discussion of engineering developments related to the experiment, attention is given to the development of proportional helium thrusters, the simulation of the attitude control system, aspects of inner loop control, the mechanization of the two-loop attitude control system, the effects of helium slosh on spacecraft pointing, and the data instrumentation system.

  4. Design properties of hydrogel tissue-engineering scaffolds

    Science.gov (United States)

    Zhu, Junmin; Marchant, Roger E

    2011-01-01

    This article summarizes the recent progress in the design and synthesis of hydrogels as tissue-engineering scaffolds. Hydrogels are attractive scaffolding materials owing to their highly swollen network structure, ability to encapsulate cells and bioactive molecules, and efficient mass transfer. Various polymers, including natural, synthetic and natural/synthetic hybrid polymers, have been used to make hydrogels via chemical or physical crosslinking. Recently, bioactive synthetic hydrogels have emerged as promising scaffolds because they can provide molecularly tailored biofunctions and adjustable mechanical properties, as well as an extracellular matrix-like microenvironment for cell growth and tissue formation. This article addresses various strategies that have been explored to design synthetic hydrogels with extracellular matrix-mimetic bioactive properties, such as cell adhesion, proteolytic degradation and growth factor-binding. PMID:22026626

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

    Directory of Open Access Journals (Sweden)

    B. Novotný

    2000-01-01

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

  6. Undergraduate engineering student experiences: Comparing sex, gender and switcher status

    Science.gov (United States)

    Fergen, Brenda Sue

    This dissertation explores undergraduate engineering experiences, comparing men with women and switchers with non-switchers. Factors related to a chilly academic climate and gender-role socialization are hypothesized to contribute to variations in men's and women's academic experiences and persistence rates. Both quantitative and qualitative data are utilized in an effort to triangulate the findings. Secondary survey data, acquired as result of a 1992 Academic Environment Survey, were utilized to test the hypothesis that sex is the most important predictor (i.e., demographic variable) of perceptions of academic climate. Regression analyses show that sex by itself is not always a significant determinant. However, when sex and college (engineering vs. other) are combined into dummy variables, they are statistically significant in models where sex was not significant alone. This finding indicates that looking at sex differences alone may be too simplistic. Thirty personal interviews were conducted with a random stratified sample of undergraduate students from the 1993 engineering cohort. The interview data indicate that differences in childhood socialization are important. With regard to persistence, differences in socialization are greater for switchers vs. non-switchers than men vs. women. Thus, gender-role socialization does not appear to play as prominent a role in women's persistence as past literature would indicate. This may be due to the self-selection process that occurs among women who choose to pursue engineering. Other aspects of childhood socialization such as parents' level of educational and occupation, students' high school academic preparation and knowledge of what to expect of college classes appear to be more important. In addition, there is evidence that, for women, male siblings play an important role in socialization. There is also evidence that women engineering students at Midwestern University face a chilly academic climate. The factors which

  7. Online Data Resources in Chemical Engineering Education: Impact of the Uncertainty Concept for Thermophysical Properties

    Science.gov (United States)

    Kim, Sun Hyung; Kang, Jeong Won; Kroenlein, Kenneth; Magee, Joseph W.; Diky, Vladimir; Muzny, Chris D.; Kazakov, Andrei F.; Chirico, Robert D.; Frenkel, Michael

    2013-01-01

    We review the concept of uncertainty for thermophysical properties and its critical impact for engineering applications in the core courses of chemical engineering education. To facilitate the translation of developments to engineering education, we employ NIST Web Thermo Tables to furnish properties data with their associated expanded…

  8. The experiences of women engineers who have completed one to five years of professional engineering employment: A phenomenological study

    Science.gov (United States)

    White, Susan M.

    Women engineers remain underrepresented in employment in engineering fields in the United States. Feminist theory views this gender disparity beyond equity in numbers for women engineers and looks at structural issues of women's access, opportunities, and quality of experience in the workplace. Research on women's success and persistence in engineering education is diverse; however, there are few studies that focus on the early years of women's careers in engineering and less using a phenomenological research design. Experiences of women engineers who have completed one to five years of professional engineering employment are presented using a phenomenological research design. Research questions explored the individual and composite experiences for the co-researchers of the study as well as challenges and advantages of the phenomenon of having completed one to five years of professional engineering employment. Themes that emanated from the data were a feeling that engineering is a positive profession, liking math and science from an early age, having experiences of attending math and science camps or learning and practicing engineering interests with their fathers for some co-researchers. Other themes included a feeling of being different as a woman in the engineering workplace, taking advantage of opportunities for training, education, and advancement to further their careers, and the role of informal and formal mentoring in developing workplace networks and engineering expertise. Co-researchers negotiated issues of management quality and support, experiences of gender discrimination in the workplace, and having to make decisions balancing their careers and family responsibilities. Finally, the women engineers for this research study expressed intentions to persist in their careers while pursuing expertise and experience in their individual engineering fields.

  9. Tissue engineering of heart valves: in vitro experiences.

    Science.gov (United States)

    Sodian, R; Hoerstrup, S P; Sperling, J S; Daebritz, S H; Martin, D P; Schoen, F J; Vacanti, J P; Mayer, J E

    2000-07-01

    Tissue engineering is a new approach, whereby techniques are being developed to transplant autologous cells onto biodegradable scaffolds to ultimately form new functional tissue in vitro and in vivo. Our laboratory has focused on the tissue engineering of heart valves, and we have fabricated a trileaflet heart valve scaffold from a biodegradable polymer, a polyhydroxyalkanoate. In this experiment we evaluated the suitability of this scaffold material as well as in vitro conditioning to create viable tissue for tissue engineering of a trileaflet heart valve. We constructed a biodegradable and biocompatible trileaflet heart valve scaffold from a porous polyhydroxyalkanoate (Meatabolix Inc, Cambridge, MA). The scaffold consisted of a cylindrical stent (1 x 15 x 20 mm inner diameter) and leaflets (0.3 mm thick), which were attached to the stent by thermal processing techniques. The porous heart valve scaffold (pore size 100 to 240 microm) was seeded with vascular cells grown and expanded from an ovine carotid artery and placed into a pulsatile flow bioreactor for 1, 4, and 8 days. Analysis of the engineered tissue included biochemical examination, enviromental scanning electron microscopy, and histology. It was possible to create a trileaflet heart valve scaffold from polyhydroxyalkanoate, which opened and closed synchronously in a pulsatile flow bioreactor. The cells grew into the pores and formed a confluent layer after incubation and pulsatile flow exposure. The cells were mostly viable and formed connective tissue between the inside and the outside of the porous heart valve scaffold. Additionally, we demonstrated cell proliferation (DNA assay) and the capacity to generate collagen as measured by hydroxyproline assay and movat-stained glycosaminoglycans under in vitro pulsatile flow conditions. Polyhydroxyalkanoates can be used to fabricate a porous, biodegradable heart valve scaffold. The cells appear to be viable and extracellular matrix formation was induced

  10. Final Report: Utilizing Alternative Fuel Ignition Properties to Improve SI and CI Engine Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Wooldridge, Margaret; Boehman, Andre; Lavoie, George; Fatouraie, Mohammad

    2017-11-30

    Experimental and modeling studies were completed to explore leveraging physical and chemical fuel properties for improved thermal efficiency of internal combustion engines. Fundamental studies of the ignition chemistry of ethanol and iso-octane blends and constant volume spray chamber studies of gasoline and diesel sprays supported the core research effort which used several reciprocating engine platforms. Single cylinder spark ignition (SI) engine studies were carried out to characterize the impact of ethanol/gasoline, syngas (H2 and CO)/gasoline and other oxygenate/gasoline blends on engine performance. The results of the single-cylinder engine experiments and other data from the literature were used to train a GT Power model and to develop a knock criteria based on reaction chemistry. The models were used to interpret the experimental results and project future performance. Studies were also carried out using a state of the art, direct injection (DI) turbocharged multi- cylinder engine with piezo-actuated fuel injectors to demonstrate the promising spray and spark timing strategies from single-cylinder engine studies on the multi-cylinder engine. Key outcomes and conclusions of the studies were: 1. Efficiency benefits of ethanol and gasoline fuel blends were consistent and substantial (e.g. 5-8% absolute improvement in gross indicated thermal efficiency (GITE)). 2. The best ethanol/gasoline blend (based on maximum thermal efficiency) was determined by the engine hardware and limits based on component protection (e.g. peak in-cylinder pressure or maximum turbocharger inlet temperature) – and not by knock limits. Blends with <50% ethanol delivered significant thermal efficiency gains with conventional SI hardware while maintain good safety integrity to the engine hardware. 3. Other compositions of fuel blends including syngas (H2 and CO) and other dilution strategies provided significant efficiency gains as well (e.g. 5% absolute improvement in ITE). 4. When the

  11. Evaluation of the tribological properties of DLC for engine applications

    International Nuclear Information System (INIS)

    Lawes, S D A; Fitzpatrick, M E; Hainsworth, S V

    2007-01-01

    Diamond-like carbon (DLC) coatings are used in automotive engines for decreasing friction and increasing durability. There are many variants of DLC films which provide a wide range of mechanical, physical and tribological properties. The films can be extremely hard (>90 GPa), give low coefficients of friction against a number of counterfaces and exhibit low wear coefficients. The films are often considered to be chemically inert. The properties of DLC films depend to a large degree on the relative proportions of graphitically- (sp 2 ) and diamond-like (sp 3 )-bonded carbon but the inclusion of elements such as hydrogen, nitrogen, silicon, tungsten, titanium, fluorine and sulphur can dramatically change their tribological response. Two different types of DLC, a WC/C amorphous hydrogenated DLC (WC/C a-C : H) coating and an amorphous hydrogenated DLC (a-C : H) have been investigated. The mechanical and tribological properties have been evaluated by nanoindentation, scratch and wear testing and friction testing in an instrumented cam-tappet testing rig. The deformation mechanisms and wear processes have been evaluated by scanning electron and atomic force microscopy. The results show that the harder a-C : H film was more wear resistant than the softer WC/C a-C : H film and performed better in the cam-tappet testing rig

  12. Contribution of engineered nanomaterials physicochemical properties to mast cell degranulation

    Science.gov (United States)

    Johnson, Monica M.; Mendoza, Ryan; Raghavendra, Achyut J.; Podila, Ramakrishna; Brown, Jared M.

    2017-03-01

    The rapid development of engineered nanomaterials (ENMs) has grown dramatically in the last decade, with increased use in consumer products, industrial materials, and nanomedicines. However, due to increased manufacturing, there is concern that human and environmental exposures may lead to adverse immune outcomes. Mast cells, central to the innate immune response, are one of the earliest sensors of environmental insult and have been shown to play a role in ENM-mediated immune responses. Our laboratory previously determined that mast cells are activated via a non-FcɛRI mediated response following silver nanoparticle (Ag NP) exposure, which was dependent upon key physicochemical properties. Using bone marrow-derived mast cells (BMMCs), we tested the hypothesis that ENM physicochemical properties influence mast cell degranulation. Exposure to 13 physicochemically distinct ENMs caused a range of mast degranulation responses, with smaller sized Ag NPs (5 nm and 20 nm) causing the most dramatic response. Mast cell responses were dependent on ENMs physicochemical properties such as size, apparent surface area, and zeta potential. Surprisingly, minimal ENM cellular association by mast cells was not correlated with mast cell degranulation. This study suggests that a subset of ENMs may elicit an allergic response and contribute to the exacerbation of allergic diseases.

  13. Globalization and Organizational Change: Engineers' Experiences and Their Implications for Engineering Education

    Science.gov (United States)

    Lucena, Juan C.

    2006-01-01

    The demand for flexible engineers presents significant challenges to engineering education. Among these is the need for engineers to be prepared to understand and deal with organizational change. Yet engineering education and research on engineers have overlooked the impact of organizational change on engineering work. After outlining the impact…

  14. Synthesis of Hollow Gold-Silver Alloyed Nanoparticles: A "Galvanic Replacement" Experiment for Chemistry and Engineering Students

    Science.gov (United States)

    Jenkins, Samir V.; Gohman, Taylor D.; Miller, Emily K.; Chen, Jingyi

    2015-01-01

    The rapid academic and industrial development of nanotechnology has led to its implementation in laboratory teaching for undergraduate-level chemistry and engineering students. This laboratory experiment introduces the galvanic replacement reaction for synthesis of hollow metal nanoparticles and investigates the optical properties of these…

  15. 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.

  16. ABB.-Combustion Engineering's Experience in Nuclear Power Plant Engineering and Construction in Korea

    International Nuclear Information System (INIS)

    Veris, James W.

    1992-01-01

    The Yonggwang Nuclear Project is a milestone project for the Korean Nuclear Industry. The Project has the two objectives of obtaining self-reliance in all aspects of nuclear technology and of constructing two modern nuclear power plants under the leadership of Korean companies acting as prime contractors. ABB.-Combustion Engineering 1000 MW System 80+ TM was chosen in 1987 as the NSLS design to meet these two objectives. This paper summarizers the significant experiences and lessons learned through the first four years of the Project as well as identifying implications for such future projects. The unique challenges of the project are identified and an evaluation of the experiences in the technology, self-reliance program and in the design and manufacturing processes will be made

  17. FROM GEOMETRY TO DIAGNOSIS: EXPERIENCES OF GEOMATICS IN STRUCTURAL ENGINEERING

    Directory of Open Access Journals (Sweden)

    B. Riveiro

    2012-07-01

    Full Text Available Terrestrial photogrammetry and laser scanning are technologies that have been successfully used for metric surveying and 3D modelling in many different fields (archaeological and architectural documentation, industrial retrofitting, mining, structural monitoring, road surveying, etc.. In the case of structural applications, these techniques have been successfully applied to 3D modelling and sometimes monitoring; but they have not been sufficiently implemented to date, as routine tools in infrastructure management systems, in terms of automation of data processing and integration in the condition assessment procedures. In this context, this paper presents a series of experiences in the usage of terrestrial photogrammetry and laser scanning in the context of dimensional and structural evaluation of structures. These experiences are particularly focused on historical masonry structures, but modern prestressed concrete bridges are also investigated. The development of methodological procedures for data collection, and data integration in some cases, is tackled for each particular structure (with access limitations, geometrical configuration, range of measurement, etc.. The accurate geometrical information provided by both terrestrial techniques motivates the implementation of such results in the complex, and sometimes slightly approximated, geometric scene that is frequently used in structural analysis. In this sense, quantitative evaluating of the influence of real and accurate geometry in structural analysis results must be carried out. As main result in this paper, a series of experiences based on the usage of photogrammetric and laser scanning to structural engineering are presented.

  18. Enhancing the engineering properties of expansive soil using bagasse ash

    Science.gov (United States)

    Silmi Surjandari, Niken; Djarwanti, Noegroho; Umri Ukoi, Nafisah

    2017-11-01

    This paper deals with stabilization of expansive soil on a laboratory experimental basis. The aim of the research was to evaluate the enhancement of the engineering properties of expansive soil using bagasse ash. The soil is treated with bagasse ash by weight (0, 5, 10, 15, and 20%) based on dry mass. The performance of bagasse ash stabilized soil was evaluated using physical and strength performance tests, namely the plasticity index, standard Proctor compaction, and percentage swelling. An X-ray diffraction (XRD) test was conducted to evaluate the clay mineral, whereas an X-ray fluorescence (XRF) was to the chemical composition of bagasse ash. From the results, it was observed that the basic tests carried out proved some soil properties after the addition of bagasse ash. Furthermore, the plasticity index decreased from 53.18 to 47.70%. The maximum dry density of the specimen increased from 1.13 to 1.24 gr/cm3. The percentage swelling decreased from 5.48 to 3.29%. The outcomes of these tests demonstrate that stabilization of expansive soils using bagasse ash can improve the strength.

  19. Gender and Satisfaction with the Cooperative Education Experience in Engineering

    Science.gov (United States)

    Wilkinson, Karen R.; Sullivan, Laura L.

    This study investigated gender differences in job satisfaction following the first term of a cooperative education program in engineering. Using data from a survey of freshmen, this study tested hypotheses about gender differences in the co-op job experience and the correlates of co-op job satisfaction. Gender-based predictive models of job satisfaction are presented. In general, the correlates of co-op job satisfaction are the same as those identified in past studies of job satisfaction. The level of co-op job satisfaction is the same for men and women, even though women do face some disadvantages. Social influences are important to both men and women, but there are gender differences in the specific predictors.

  20. Experiment with expert system guidance of an engineering analysis task

    International Nuclear Information System (INIS)

    Ransom, V.H.; Fink, R.K.; Callow, R.A.

    1986-01-01

    An experiment is being conducted in which expert systems are used to guide the performance of an engineering analysis task. The task chosen for experimentation is the application of a large thermal hydraulic transient simulation computer code. The expectation from this work is that the expert system will result in an improved analytical result with a reduction in the amount of human labor and expertise required. The code associated functions of model formulation, data input, code execution, and analysis of the computed output have all been identified as candidate tasks that could benefit from the use of expert systems. Expert system modules have been built for the model building and data input task. Initial results include the observation that human expectations of an intelligent environment rapidly escalate and structured or stylized tasks that are tolerated in the unaided system are frustrating within the intelligent environment

  1. First Year Experiences in School of Mechanical Engineering Kanazawa University

    Science.gov (United States)

    Kinari, Toshiyasu; Kanjin, Yuichi; Furuhata, Toru; Tada, Yukio

    This paper reports two lectures of the first year experience, ‧Lecture on Life in Campus and Society‧ and ‧Freshman Seminar‧ and discusses their effects. Both lectures have been given freshmen of the school of mechanical engineering, Kanazawa University in H20 spring term. The former lecture is aimed at freshmen to keep on a proper way in both social and college life. It consists of normal class and e-learning system lectures. E-learning system examination requires students to review the whole text book and that seems to have brought better results in the survey. The latter seminar is aimed at freshmen to get active and self-disciplined learning way through their investigation, discussion, presentation, writing work, and so on.

  2. A phenomenographic study of students' experiences with transition from pre-college engineering programs to first-year engineering

    Science.gov (United States)

    Salzman, Noah

    Recent national dialogues on the importance of preparing more students for careers in Science, Technology, Engineering, and Mathematics has driven the development of formal and informal learning opportunities for children and adolescents to explore engineering. Despite the growth of these programs, relatively little research exists on how participation in these programs affects students who choose to pursue further study in engineering. The present study addressed this gap through an exploration of the different ways that First-Year Engineering students experience the transition from pre-college engineering to undergraduate engineering studies. Given the focus of this research on students' experiences, phenomenography was chosen to explore the phenomenon of transition from pre-college to first-year engineering at a large, public Midwestern university. This facilitated understanding the range of variation in the ways that students experienced this transition. Twenty-two students with different amounts of participation in a variety of different engineering programs were selected to be interviewed using a purposeful maximum variation sampling strategy. The interviews were guided by a semi-structured interview protocol that encouraged the participants to reflect on their pre-college engineering experiences, their experiences in First-Year Engineering, and the transition between the two domains. The interviews were analyzed using phenomenographic methods to develop an outcome space consisting of five qualitatively different but related ways of experiencing the transition from pre-college to First-Year Engineering. These categories of description included Foreclosure, Frustration, Tedium, Connection, and Engaging Others. With the exception of the first category which was characterized by a lack of passion and commitment to engineering, the remaining four categories formed a hierarchical relationship representing increasing integration in First-Year Engineering. The

  3. Experiment and Simulation Study of Single Cylinder Diesel Engine Performance, Using Soybean Oil Biodiesel

    Directory of Open Access Journals (Sweden)

    Muhammad Rizqi Ariefianto

    2017-01-01

    Full Text Available Abstract— The most common fuel uses in the world is made from fossil. Fossil fuel is categorized as a non-renewable energy source. For that reason, there should be an alternative fuel to replace fossil fuel by using biodiesel and one of the stock comes from soybean bean. Before using the biodiesel made from soybean bean oil, there should be a research to find out the properties and the effect of biodiesel from soybean bean oil regarding the performance of the engine. The research can be conducted in experiment and simulation. The properties result of soybean oil biodiesel should be tested to confirm whether this biodiesel have meet the standard requirement of biodieselor not. This biodiesel sproperties are Flash Point value is 182 o C , Pour Point value is -7 o C, Density at 15 o C is 890 Kg/m3, Kinematic Viscosity at 40 o C is 5.58 (cSt, and Lower Heating Value is 42.27686 MJ/kg. The result from this research is the highest power from simulation is 9% higher than the experiment. The highest torque from the experiment is 37% lower than the simulation’s torque. Lowest SFOC from experiment is  28% lower than the simulation’s SFOC. Highest BMEP from simulation is 20% higher than the highest BMEP from experiment. The  highest thermal efficiency from experiment is 6% higher than the highest thermal efficiency from simulation. The engine performance result using soybean oil biodiesel is not better than the Pertamina Dex. For that reason, the use of this biodiesel is not suggested to substitute Pertamina Dex.

  4. The research on teaching reformation of photoelectric information science and engineering specialty experiments

    Science.gov (United States)

    Zhu, Zheng; Yang, Fan; Zhang, Yang; Geng, Tao; Li, Yuxiang

    2017-08-01

    This paper introduced the idea of teaching reformation of photoelectric information science and engineering specialty experiments. The teaching reformation of specialty experiments was analyzed from many aspects, such as construction of specialized laboratory, experimental methods, experiment content, experiment assessing mechanism, and so on. The teaching of specialty experiments was composed of four levels experiments: basic experiments, comprehensive and designing experiments, innovative research experiments and engineering experiments which are aiming at enterprise production. Scientific research achievements and advanced technology on photoelectric technology were brought into the teaching of specialty experiments, which will develop the students' scientific research ability and make them to be the talent suitable for photoelectric industry.

  5. Engineering of the divertor injection tokamak experiment (DITE)

    International Nuclear Information System (INIS)

    Plummer, K.M.; Bayes, D.V.; Bell, D.; Burt, J.; Galloway, F.; Sanders, B.C.; Skelton, D.E.; Varley, G.L.

    1976-01-01

    The DITE assembly has been constructed to study the effect of powerful neutral injection and the use of magnetic divertors in Tokamak systems. In addition, the plasma is stabilized by a position controlled feed-back vertical field system developed from results on the CLEO experiment, and added to DITE later in the design stage. The machine is designed for an ultimate plasma current of 340 kA, having a minor radius of 23 cm at q = 2, on a major radius of 113 cm. The 28 kG Bphi field, from 16 liquid nitrogen cooled coils has a 2% ripple at the edge of the plasma. The divertor is a ''bundle'' type, the present design of which is limited to operating in a Bphi field of 18 kG. Neutral Injection, initially by two, and ultimately by four injectors, is intended to supply about 1,500 kW of beam power. The engineering is now complete and the machine commissioned; this paper describes the up-to-date design of the machine and includes some of our experiences during design, construction and commissioning

  6. Diesel Surrogate Fuels for Engine Testing and Chemical-Kinetic Modeling: Compositions and Properties.

    Science.gov (United States)

    Mueller, Charles J; Cannella, William J; Bays, J Timothy; Bruno, Thomas J; DeFabio, Kathy; Dettman, Heather D; Gieleciak, Rafal M; Huber, Marcia L; Kweon, Chol-Bum; McConnell, Steven S; Pitz, William J; Ratcliff, Matthew A

    2016-02-18

    The primary objectives of this work were to formulate, blend, and characterize a set of four ultralow-sulfur diesel surrogate fuels in quantities sufficient to enable their study in single-cylinder-engine and combustion-vessel experiments. The surrogate fuels feature increasing levels of compositional accuracy (i.e., increasing exactness in matching hydrocarbon structural characteristics) relative to the single target diesel fuel upon which the surrogate fuels are based. This approach was taken to assist in determining the minimum level of surrogate-fuel compositional accuracy that is required to adequately emulate the performance characteristics of the target fuel under different combustion modes. For each of the four surrogate fuels, an approximately 30 L batch was blended, and a number of the physical and chemical properties were measured. This work documents the surrogate-fuel creation process and the results of the property measurements.

  7. Engineering Properties of Bentonite Stabilized with Lime and Phosphogypsum

    Directory of Open Access Journals (Sweden)

    Kumar Sujeet

    2014-12-01

    Full Text Available Engineering properties such as compaction, unconfined compressive strength, consistency limits, percentage swell, free swell index, the California bearing ratio and the consolidation of bentonite stabilized with lime and phosphogypsum are presented in this paper. The content of the lime and phosphogypsum varied from 0 to 10 %. The results reveal that the dry unit weight and optimum moisture content of bentonite + 8 % lime increased with the addition of 8 % phosphogypsum. The percentage of swell increased and the free swell index decreased with the addition of 8 % phosphogypsum to the bentonite + 8 % lime mix. The unconfined compressive strength of the bentonite + 8 % lime increased with the addition of 8 % phosphogypsum as well as an increase in the curing period up to 14 days. The liquid limit and plastic limit of the bentonite + 8 % lime increased, whereas the plasticity index remained constant with the addition of 8 % phosphogypsum. The California bearing ratio, modulus of subgrade reaction, and secant modulus increased for the bentonite stabilized with lime and phosphogypsum. The coefficient of the consolidation of the bentonite increased with the addition of 8 % lime and no change with the addition of 8 % phosphogypsum.

  8. Improving the mechanical properties of collagen-based membranes using silk fibroin for corneal tissue engineering.

    Science.gov (United States)

    Long, Kai; Liu, Yang; Li, Weichang; Wang, Lin; Liu, Sa; Wang, Yingjun; Wang, Zhichong; Ren, Li

    2015-03-01

    Although collagen with outstanding biocompatibility has promising application in corneal tissue engineering, the mechanical properties of collagen-based scaffolds, especially suture retention strength, must be further improved to satisfy the requirements of clinical applications. This article describes a toughness reinforced collagen-based membrane using silk fibroin. The collagen-silk fibroin membranes based on collagen [silk fibroin (w/w) ratios of 100:5, 100:10, and 100:20] were prepared by using silk fibroin and cross-linking by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide. These membranes were analyzed by scanning electron microscopy and their optical property, and NaCl and tryptophan diffusivity had been tested. The water content was found to be dependent on the content of silk fibroin, and CS10 membrane (loading 10 wt % of silk fibroin) performed the optimal mechanical properties. Also the suture experiments have proved CS10 has high suture retention strength, which can be sutured in rabbit eyes integrally. Moreover, the composite membrane proved good biocompatibility for the proliferation of human corneal epithelial cells in vitro. Lamellar keratoplasty shows that CS10 membrane promoted complete epithelialization in 35 ± 5 days, and their transparency is restored quickly in the first month. Corneal rejection reaction, neovascularization, and keratoconus are not observed. The composite films show potential for use in the field of corneal tissue engineering. © 2014 Wiley Periodicals, Inc.

  9. The effect of additives on properties, performance and emission of biodiesel fuelled compression ignition engine

    International Nuclear Information System (INIS)

    Rashedul, H.K.; Masjuki, H.H.; Kalam, M.A.; Ashraful, A.M.; Ashrafur Rahman, S.M.; Shahir, S.A.

    2014-01-01

    of various additives on biodiesel properties, engine performance and exhaust emission characteristics and the corresponding effect factors were surveyed and analyzed in detail. The review concludes that the use of additive in biodiesel fuel is inalienable both for improving properties and for better engine performance and emission control. Therefore, in order to find the appropriate fuel additives in the combustion applications, more experiments are needed to explore the different related mechanisms

  10. Estimation of sediment properties during benthic impact experiments

    Digital Repository Service at National Institute of Oceanography (India)

    Yamazaki, T.; Sharma, R

    Sediment properties, such as water content and density, have been used to estimate the dry and wet weights, as well as the volume of sediment recovered and discharged, during benthic impact experiments conducted in the Pacific and Indian Oceans...

  11. EDF's Engineering Experience and Contribution to the Nuclear Development

    International Nuclear Information System (INIS)

    Salha, Bernard; Fourest, Bernard; Arpino, Jean-Marc

    2002-01-01

    Electricite de France (EDF) is now operating 58 nuclear power units which produce 76% of the electricity generated in France. This EDF's industrial success is the result of its capacity to master and optimize its production tool, from design through operation. EDF's integrated engineering is in the heart of this process of technical expertise and economic optimization. It allows to be in interface between the needs of operators and industrials suppliers, while accumulating a significant feedback of operating experience. The will of achieving the process of frenchifying PWR technology and to implement new industrial innovations have ended up in the new NPP of 100 % french design, the N4 series and its significant innovations. EDF energy policy is to keep the nuclear option open for the future. This strategy results from the need to improve the availability and the life extension of the units in operation and to prepare the replacement of the operating reactors around 2015. This is the objective of the European Pressurized Reactor (EPR), a French-German joint project. EDF is also applying this industrial process in its international projects. For example China, which desires to implement a standardized nuclear program and to move forward the complete autonomy of its nuclear industry, has decided to adopt a similar approach to EDF's one. (authors)

  12. Experience of Developing a Meta-Semantic Search Engine

    OpenAIRE

    Mukhopadhyay, Debajyoti; Sharma, Manoj; Joshi, Gajanan; Pagare, Trupti; Palwe, Adarsha

    2013-01-01

    Thinking of todays web search scenario which is mainly keyword based, leads to the need of effective and meaningful search provided by Semantic Web. Existing search engines are vulnerable to provide relevant answers to users query due to their dependency on simple data available in web pages. On other hand, semantic search engines provide efficient and relevant results as the semantic web manages information with well defined meaning using ontology. A Meta-Search engine is a search tool that ...

  13. Shape Memory Polymers: A Joint Chemical and Materials Engineering Hands-On Experience

    Science.gov (United States)

    Seif, Mujan; Beck, Matthew

    2018-01-01

    Hands-on experiences are excellent tools for increasing retention of first year engineering students. They also encourage interdisciplinary collaboration, a critical skill for modern engineers. In this paper, we describe and evaluate a joint Chemical and Materials Engineering hands-on lab that explores cross-linking and glass transition in…

  14. Psychometric properties of the Dissociative Experiences Scale.

    Science.gov (United States)

    Dubester, K A; Braun, B G

    1995-04-01

    The test-retest reliability of the Dissociative Experiences Scale (DES; Bernstein EM, Putnam FW [1986] Development, reliability, and validity of a dissociation scale. The Journal of Nervous and Mental Disease 174:727-735) in a clinical sample was found to be .93 for the total DES score and .95, .89, and .82 for the three subscale scores of amnesia, depersonalization-derealization, and absorption (dissociative identity disorder [DID], DSM-IV), respectively. Test-retest reliabilities within diagnostic groups of multiple personality disorder, dissociative disorder not otherwise specified, and a general other category of psychiatric diagnoses were obtained for total and subscale scores on the DES. These ranged from .78 to .96. Tests of mean scores across the two test sessions showed the total and subscale scores to be temporally stable. The DES was also found to be highly internally consistent: Cronbach's alphas of .96 and .97 were observed for the total DES scores taken at times 1 and 2, respectively. Construct validity of the DES was demonstrated by differentiation among the subscale scores in a repeated-measures analysis of variance (F[2,154] = 32.03, p < or = .001). Normality and general distribution issues were also addressed and provided a rationale for using the DES with parametric statistics. Reasons why the DES (as it was originally designed) is not appropriate as a dependent measure in outcome research are discussed, along with needed future research. Implications of the findings for the clinical usefulness of the DES as a diagnostic instrument are noted.

  15. Psychometric properties of the Violent Experiences Questionnaire.

    Science.gov (United States)

    King, Alan R; Russell, Tiffany D

    2017-05-01

    The Violent Experiences Questionnaire-Revised (VEQ-R) is a brief retrospective self-report inventory which provides estimates of annual frequencies of childhood physical abuse, sibling physical abuse, exposure to parental violence, peer bullying, and corporal punishment as they were experienced from ages 5 to 16. The VEQ-R indices rely on a frequency metric that estimates the number of days on average per year a specified class of behavior occurred over a 12year retrospective period. All scores range from a frequency of 0 to a high of 104. Scale normative data was generated from both a college (N=1266) and national (N=1290) sample to expand the research applicability of this relatively new inventory. Subscales were added to estimate the frequency of victimization during childhood, the pre-teen years, and adolescence. Four "hostility" component indices were derived from perpetrator source (parent, sibling, peer, or domestic). Thresholds were established to for High, Moderate, Low, and No Risk classifications. Subscales dimensions were found to have both adequate internal and temporal consistency. Evidence of concurrent and discriminant validity was generated using the Parent-Child Conflict Tactics Scale-Short-Form © , LONGSCAN Physical Abuse Self-Report scale, and Physical Punishment scale of the Assessing Environments III inventory. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Experiences with Integrating Simulation into a Software Engineering Curriculum

    Science.gov (United States)

    Bollin, Andreas; Hochmuller, Elke; Mittermeir, Roland; Samuelis, Ladislav

    2012-01-01

    Software Engineering education must account for a broad spectrum of knowledge and skills software engineers will be required to apply throughout their professional life. Covering all the topics in depth within a university setting is infeasible due to curricular constraints as well as due to the inherent differences between educational…

  17. 3D engineered models for highway construction : the Iowa experience.

    Science.gov (United States)

    2015-06-01

    3D engineered modeling is a relatively new and developing technology that can provide numerous bene ts to owners, engineers, : contractors, and the general public. This manual is for highway agencies that are considering or are in the process of s...

  18. Experiences on dynamic simulation software in chemical engineering education

    DEFF Research Database (Denmark)

    Komulainen, Tiina M.; Enemark-rasmussen, Rasmus; Sin, Gürkan

    2012-01-01

    Commercial process simulators are increasing interest in the chemical engineer education. In this paper, the use of commercial dynamic simulation software, D-SPICE® and K-Spice®, for three different chemical engineering courses is described and discussed. The courses cover the following topics...

  19. Turkish Students' Career Choices in Engineering: Experiences from Turkey

    Science.gov (United States)

    Cavas, Bulent; Cakiroglu, Jale; Cavas, Pinar; Ertepinar, Hamide

    2011-01-01

    The shortfall of young people, particularly women, in the field of Science, Mathematics and Engineering (SME) has been shown in many national studies. Schreiner and Sjoberg (2007) indicated that boys outnumber girls in physics and engineering studies, while the gender balance is shifted towards the girls in studies including medicine, veterinary…

  20. 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

  1. Enhancing the Programming Experience for First-Year Engineering Students through Hands-On Integrated Computer Experiences

    Science.gov (United States)

    Canfield, Stephen L.; Ghafoor, Sheikh; Abdelrahman, Mohamed

    2012-01-01

    This paper describes the redesign and implementation of the course, "Introduction to Programming for Engineers" using microcontroller (MCU) hardware as the programming target. The objective of this effort is to improve the programming competency for engineering students by more closely relating the initial programming experience to the student's…

  2. Supervisor's experiments on radiation safety trainings in school of engineering

    International Nuclear Information System (INIS)

    Nomura, Kiyoshi

    2005-01-01

    Radiation safety training courses in School of Engineering, The University of Tokyo, were introduced. The number of radiation workers and the usage of radiation and radioisotopes have been surveyed for past 14 years. The number of radiation workers in School of Engineering has increased due to the treatment of X-ray analysis of materials, recently. It is important for workers to understand the present situation of School of Engineering before the treatment of radiation and radioisotopes. What the supervisor should tell to radiation workers were presented herewith. The basic questionnaires after the lecture are effective for radiation safety trainings. (author)

  3. Experimental datasets on engineering properties of expansive soil treated with common salt

    Directory of Open Access Journals (Sweden)

    Taiwo O. Durotoye

    2018-06-01

    Full Text Available Construction of highway pavements or high rise structures over the expansive soils are always problematic due to failures of volume change or swelling characteristic experienced in the water permeability of the soil. The data in this article represented summary of (Durotoye et al., 2016; Durotoye, 2016 [1,2]. The data explored different percentages of sodium chloride as additive in stabilizing the engineering properties of expansive soil compared with other available stabilizer previously worked on. Experimental procedures carried out on expansive soil include: (Liquid limit, Plastic limit, Plasticity index, Shrinkage limit, Specific gravity Free swell index and Optimum water content to determine the swelling parameters and (maximum dry density, California bearing ratio and unconfined compressive strength to determine the strength parameters. The results of the experiment were presented in pie charts. Keywords: Common salt, Expansive soil, Experimental procedure, Strength parameters, Swelling parameters

  4. Experimental datasets on engineering properties of expansive soil treated with common salt.

    Science.gov (United States)

    Durotoye, Taiwo O; Akinmusuru, Joseph O; Ogundipe, Kunle E

    2018-06-01

    Construction of highway pavements or high rise structures over the expansive soils are always problematic due to failures of volume change or swelling characteristic experienced in the water permeability of the soil. The data in this article represented summary of (Durotoye et al., 2016; Durotoye, 2016) [1], [2]. The data explored different percentages of sodium chloride as additive in stabilizing the engineering properties of expansive soil compared with other available stabilizer previously worked on. Experimental procedures carried out on expansive soil include: (Liquid limit, Plastic limit, Plasticity index, Shrinkage limit, Specific gravity Free swell index and Optimum water content) to determine the swelling parameters and (maximum dry density, California bearing ratio and unconfined compressive strength) to determine the strength parameters. The results of the experiment were presented in pie charts.

  5. Quasi-Experiments and Hedonic Property Value Methods

    OpenAIRE

    Christopher F. Parmeter; Jaren C. Pope

    2012-01-01

    There has recently been a dramatic increase in the number of papers that have combined quasi-experimental methods with hedonic property models. This is largely due to the concern that cross-sectional hedonic methods may be severely biased by omitted variables. While the empirical literature has developed extensively, there has not been a consistent treatment of the theory and methods of combining hedonic property models with quasi-experiments. The purpose of this chapter is to fill this void....

  6. Engineering properties of stabilized subgrade soils for implementation of the AASHTO 2002 pavement design guide.

    Science.gov (United States)

    2009-06-01

    A comprehensive laboratory study was undertaken to determine engineering properties of cementitiously stabilized common subgrade soils in Oklahoma for the design of roadway pavements in accordance with the AASHTO 2002 Mechanistic-Empirical Pavement D...

  7. Intermittent straining accelerates the development of tissue properties in engineered heart valve tissue

    NARCIS (Netherlands)

    Rubbens, M.P.; Mol, A.; Boerboom, R.A.; Bank, R.A.; Baaijens, F.P.T.; Bouten, C.V.C.

    2009-01-01

    Tissue-engineered heart valves lack sufficient amounts of functionally organized structures and consequently do not meet in vivo mechanical demands. To optimize tissue architecture and hence improve mechanical properties, various in vitro mechanical conditioning protocols have been proposed, of

  8. Sensitivities of Internal Combustion Automotive Engines to Variations in Fuel Properties

    Science.gov (United States)

    1982-02-01

    An assessment of the sensitivity of the automotive gasoline and diesel engines to variations in fuel properties has been made. The variables studied include H/C ratio, distillation range, aromatic content, ignition quality as determined by the octane...

  9. Local Government Planning Tool to Calculate Institutional and Engineering Control Costs for Brownfield Properties

    Science.gov (United States)

    This cost calculator is designed as a guide for municipal or local governments to assist in calculating their expected costs of implementing and conducting long-term stewardship of institutional controls and engineering controls at brownfield properties.

  10. Alvar engine. An engine with variable compression ratio. Experiments and tests

    Energy Technology Data Exchange (ETDEWEB)

    Erlandsson, Olof

    1998-09-01

    This report is focused on tests with Variable Compression Ratio (VCR) engines, according to the Alvar engine principle. Variable compression ratio means an engine design where it is possible to change the nominal compression ratio. The purpose is to increase the fuel efficiency at part load by increasing the compression ratio. At maximum load, and maybe supercharging with for example turbocharger, it is not possible to keep a high compression ratio because of the knock phenomena. Knock is a shock wave caused by self-ignition of the fuel-air mix. If knock occurs, the engine will be exposed to a destructive load. Because of the reasons mentioned it would be an advantage if it would be possible to change the compression ratio continuously when the load changes. The Alvar engine provides a solution for variable compression ratio based on well-known engine components. This paper provides information about efficiency and emission characteristics from tests with two Alvar engines. Results from tests with a phase shift mechanism (for automatic compression ratio control) for the Alvar engine are also reviewed Examination paper. 5 refs, 23 figs, 2 tabs, 5 appendices

  11. Introducing systems engineering to industrial design engineering students with hands-on experience

    NARCIS (Netherlands)

    Bonnema, Gerrit Maarten; Lutters-Weustink, Ilanit F.; van Houten, Frederikus J.A.M.; Selvaraj, H.; Muthukumar, V.

    2005-01-01

    The article presents an innovative educational project to introduce systems engineering to third year students in industrial design engineering at the University of Twente. In a short period the students are confronted with new technology, namely sensors and actuators. They have to apply this

  12. An Experiment in Integrating an Engineering Communication Toolkit into the Industrial Engineering Curriculum

    Science.gov (United States)

    2011-01-31

    A recent survey on the working habits of professional engineers found that nearly 2/3 of their day is spent communicating with others, while only 1/3 is spent on tasks commonly associated with engineering (Sageev & Romanowski, 2001). Whether it is fa...

  13. Engineering properties of the crude oil–contaminated soils of Niger ...

    African Journals Online (AJOL)

    There was a reverse trend when soil samples with appreciable percentages of sand and crude oil of low THC were used. The knowledge of these will aid geotechnical engineers on their designs and remediation techniques. Keywords: Engineering properties, soils, crude oil, hydrocarbon, Niger Delta, Nigeria ...

  14. International conference on the performance of engineered barriers. Physical and chemical properties, behaviour and evolution. Short abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Schaefers, Annika; Fahland, Sandra (eds.)

    2014-08-01

    The volume includes the abstracts of the papers presented at the international conference on the performance of engineered barrier systems, their physical and chemical properties, behavior and evolution. The papers cover the topics bentonite buffers, radioactive waste repository safety, geophysical and geochemical property monitoring, repository sealing materials, thermo-hydro-mechanical characterization, gas injection tests, hydration and heating tests, clay-iron interaction experiments, water retention behavior, thermal stability of materials, numerical modeling studies, long-term simulations, thermo-hydrologic phenomena, uncertainty and sensitivity studies, probabilistic assessments, preliminary safety analyses of Gorleben.

  15. Software Engineering Researchers' Attitudes on Case Studies and Experiments: an Exploratory Survey

    OpenAIRE

    Tofan, Dan; Galster, Matthias; Avgeriou, Paris; Weyns, Danny

    2011-01-01

    Background: Case studies and experiments are research methods frequently applied in empirical software engineering. Experiments are well-­understood and their value as an empirical method is recognized. On the other hand, there seem to be different opinions on what constitutes a case study, and about the value of case studies as a thorough research method. Aim: We aim at exploring the attitudes of software engineering researchers on case studies and experiments. Furthermore, we investigate ho...

  16. Female peer mentors early in college increase women's positive academic experiences and retention in engineering.

    Science.gov (United States)

    Dennehy, Tara C; Dasgupta, Nilanjana

    2017-06-06

    Scientific and engineering innovation is vital for American competitiveness, quality of life, and national security. However, too few American students, especially women, pursue these fields. Although this problem has attracted enormous attention, rigorously tested interventions outside artificial laboratory settings are quite rare. To address this gap, we conducted a longitudinal field experiment investigating the effect of peer mentoring on women's experiences and retention in engineering during college transition, assessing its impact for 1 y while mentoring was active, and an additional 1 y after mentoring had ended. Incoming women engineering students ( n = 150) were randomly assigned to female or male peer mentors or no mentors for 1 y. Their experiences were assessed multiple times during the intervention year and 1-y postintervention. Female (but not male) mentors protected women's belonging in engineering, self-efficacy, motivation, retention in engineering majors, and postcollege engineering aspirations. Counter to common assumptions, better engineering grades were not associated with more retention or career aspirations in engineering in the first year of college. Notably, increased belonging and self-efficacy were significantly associated with more retention and career aspirations. The benefits of peer mentoring endured long after the intervention had ended, inoculating women for the first 2 y of college-the window of greatest attrition from science, technology, engineering, and mathematics (STEM) majors. Thus, same-gender peer mentoring for a short period during developmental transition points promotes women's success and retention in engineering, yielding dividends over time.

  17. Solar Climate Engineering and Intellectual Property : Toward a Research Commons

    NARCIS (Netherlands)

    Reynolds, Jesse|info:eu-repo/dai/nl/363244638; Contreras, Jorge L; Sarnoff, Joshua D

    2017-01-01

    Climate change is one of the greatest challenges confronting society today. Solar climate engineering (SCE) has the potential to reduce climate risks substantially. This controversial technology would make the earth more reflective in order to counteract global warming. The science of SCE is still

  18. improvement of engineering properties of igbokoda standard sand

    African Journals Online (AJOL)

    eobe

    concentrations of 1%, 2%, 3%, 4% and 5% by mass of the soil sample. Direct shear test .... Review of Plastic and HDPE wastes use for soil improvement and in ..... Soil Stabilizer, Final Year Project report, Department of Civil Engineering ...

  19. MANAGING CONFLICT IN ENGINEERING PROJECTS: NEW ZEALAND EXPERIENCES

    Directory of Open Access Journals (Sweden)

    Nicola Naismith

    2016-07-01

    Full Text Available There is a wealth of knowledge concerning conflict management and its resolution in the workplace, however there is a dearth of information relating to conflict management and its resolution in engineering project management. This paper set out to examine the reality of conflict management in engineering project management in New Zealand. This was achieved through a review of credible literature sources and the completion of a pilot study to gain subject matter expert perspectives. The research suggests that conflicts can be destructive, resulting in anxiety and strong emotional responses leading to reflexive reactions including avoidance, aggression, fight, hostility and a breakdown in communications and relationships. Findings indicate that managing a project structure is synonymous with handling conflict and these disagreements can be detrimental to the success of a project. The initial results suggest that a number of factors act as drivers of conflict in engineering projects in New Zealand. These drivers are: power, personality, group dynamics and organisation culture. The conflict resolution tools cited as being widely used for engineering projects are collaboration and negotiation. The paper also offers recommendations for future research.

  20. Cell Formation in Industrial Engineering : Theory, Algorithms and Experiments

    NARCIS (Netherlands)

    Goldengorin, B.; Krushynskyi, D.; Pardalos, P.M.

    2013-01-01

    This book focuses on a development of optimal, flexible, and efficient models and algorithms for cell formation in group technology. Its main aim is to provide a reliable tool that can be used by managers and engineers to design manufacturing cells based on their own preferences and constraints

  1. Recent Efforts and Experiments in the Construction of Aviation Engines

    Science.gov (United States)

    SCHWAGER

    1920-01-01

    It became evident during World War I that ever-increasing demands were being placed on the mean power of aircraft engines as a result of the increased on board equipment and the demands of aerial combat. The need was for increased climbing efficiency and climbing speed. The response to these demands has been in terms of lightweight construction and the adaptation of the aircraft engine to the requirements of its use. Discussed here are specific efforts to increase flying efficiency, such as reduction of the number of revolutions of the propeller from 1400 to about 900 r.p.m. through the use of a reduction gear, increasing piston velocity, locating two crankshafts in one gear box, and using the two-cycle stroke. Also discussed are improvements in the transformation of fuel energy into engine power, the raising of compression ratios, the use of super-compression with carburetors constructed for high altitudes, the use of turbo-compressors, rotary engines, and the use of variable pitch propellers.

  2. Contracting for engineering services: Experience with innovative fee arrangements

    International Nuclear Information System (INIS)

    Criner, D.E.; Schenk, J.L.

    1995-01-01

    The relationship between an engineering firm and a client can be favorably influenced by a clearly defined incentive plan. This paper addresses several approaches and the advantages and disadvantages of each. It also summarizes the lessons learned to date in using incentive fee arrangements

  3. ATS-6 engineering performance report. Volume 4: Television experiments

    Science.gov (United States)

    Wales, R. O. (Editor)

    1981-01-01

    Experiments sponsored by the US Department of Health Education and Welfare are discussed, including telecommunications, Alaskan health service, Appalachian education satellite project, and the University of the West Indies. The Satellite Instructional Television Experiment in India is reviewed. Independent television experiments are addressed, including AIDSAT and Project Look Up.

  4. Combustion Property Analysis and Control System for the Dynamics of a Single Cylinder Diesel Engine

    Directory of Open Access Journals (Sweden)

    Bambang Wahono

    2013-12-01

    Full Text Available Corresponding to global environment problems in recent year, the technology for reducing fuel consumption and exhaust gas emission of engine was needed. Simulation of transient engine response is needed to predict engine performance that frequently experience rapid changes of speed. The aim of this research is to develop a non-linear dynamic control model for direct injection single cylinder diesel engine which can simulate engine performance under transient conditions. In this paper, the combustion model with multistage injection and conducted experiments in the transient conditions to clarify the combustion characteristics was proposed. In order to perform the analysis of acceleration operation characteristics, it was built a Model Predictive Control (MPC to reproduce the characteristic values of the exhaust gas and fuel consumption from the control parameters in particular. Finally, MPC is an effective method to perform the analysis of characteristic in diesel engine under transient conditions.

  5. First-Hand Experience with Engineering Design and Career Interest in Engineering: An Informal STEM Education Case Study

    Science.gov (United States)

    Ayar, Mehmet C.

    2015-01-01

    The purpose of this study is to present students' experiences, interest in engineering, and personal narratives while participating in a robotics summer camp in a metropolitan city in Turkey. In this study, I used qualitative data collection methods such as interviews, field notes, and observations. I used the four principles of Engle and Conant…

  6. Software engineering knowledge at your fingertips: Experiences with a software engineering-portal

    OpenAIRE

    Punter, T.; Kalmar, R.

    2003-01-01

    In order to keep up the pace with technology development, knowledge on Software Engineering (SE) methods, techniques, and tools is required. For an effective and efficient knowledge transfer, especially Small and Medium-sized Enterprises (SMEs) might benefit from Software Engineering Portals (SE-Portals). This paper provides an analysis of SE-Portals by distinguishing two types: 1) the Knowledge Portal and 2) the Knowledge & Community Portal. On behalf of the analysis we conclude that most SE...

  7. Simulations of the magnetic properties experiment on Mars Exploration Rovers

    International Nuclear Information System (INIS)

    Gunnlaugsson, H. P.; Worm, E. S.; Bertelsen, P.; Goetz, W.; Kinch, K.; Madsen, M. B.; Merrison, J. P.; Nornberg, P.

    2005-01-01

    We present some of the main findings from simulation studies of the Magnetic Properties Experiment on the Mars Exploration Rovers. The results suggest that the dust has formed via mechanical breakdown of surface rocks through the geological history of the planet, and that liquid water need not have played any significant role in the dust formation processes.

  8. Nuclear engineering experiments at experimental facilities of JNC in graduate course of Tokyo Institute of Technology

    International Nuclear Information System (INIS)

    Hayashizaki, Noriyosu; Takahashi, Minoru; Aoyama, Takafumi; Onose, Shoji

    2005-01-01

    Nuclear engineering experiments using outside facilities of the campus have been offered for graduate students in the nuclear engineering course in Tokyo Institute of Technology (Tokyo Tech.). The experiments are managed with the collaboration of Japan Nuclear Cycle Development Institute (JNC), Japan Atomic Energy Research Institute (JAERI) and Research Reactor Institute, Kyoto University (KUR). This report presents the new curriculum of the nuclear engineering experiments at JNC since 2002. The change is due to the shutdown of Deuterium Criticality Assembly Facility (DCA) that was used as an experimental facility until 2001. Reactor physics experiment using the training simulator of the experimental fast reactor JOYO is continued from the previous curriculum with the addition of the criticality approach experiment and control rods calibration. A new experimental subject is an irradiated material experiment at the Material Monitoring Facility (MMF). As a result, both are acceptable as the student experiments on the fast reactor. (author)

  9. Gaming, texting, learning? Teaching engineering ethics through students' lived experiences with technology.

    Science.gov (United States)

    Voss, Georgina

    2013-09-01

    This paper examines how young peoples' lived experiences with personal technologies can be used to teach engineering ethics in a way which facilitates greater engagement with the subject. Engineering ethics can be challenging to teach: as a form of practical ethics, it is framed around future workplace experience in a professional setting which students are assumed to have no prior experience of. Yet the current generations of engineering students, who have been described as 'digital natives', do however have immersive personal experience with digital technologies; and experiential learning theory describes how students learn ethics more successfully when they can draw on personal experience which give context and meaning to abstract theories. This paper reviews current teaching practices in engineering ethics; and examines young people's engagement with technologies including cell phones, social networking sites, digital music and computer games to identify social and ethical elements of these practices which have relevance for the engineering ethics curricula. From this analysis three case studies are developed to illustrate how facets of the use of these technologies can be drawn on to teach topics including group work and communication; risk and safety; and engineering as social experimentation. Means for bridging personal experience and professional ethics when teaching these cases are discussed. The paper contributes to research and curriculum development in engineering ethics education, and to wider education research about methods of teaching 'the net generation'.

  10. Top Quark Properties Measurements with the ATLAS Experiment

    International Nuclear Information System (INIS)

    Quijada, J A Murillo

    2016-01-01

    Results on recent measurements of top quark properties with the ATLAS experiment at the European Laboratory, CERN, are shown. The measurements are performed using the full data set recorded during the LHC Run-I. The full data set consists of a collected integrated luminosities ∫Tdt of 4.6 fb -1 recorded at a proton-proton collision energy of √ s = 7 TeV and 20.3 fb -1 collected at 8 TeV. The mentioned top quark properties include: spin correlation, charge asymmetry, W-boson polarization, color flow, top mass and top width in events with a top and anti-top quark pair ( tt ). An introduction to the LHC and the ATLAS detector is included and latest main results from this experiment. The contents include the current world benchmark results for the different properties and plans for future measurements during the ongoing LHC Run-II. (paper)

  11. Quality of Design, Analysis and Reporting of Software Engineering Experiments:A Systematic Review

    OpenAIRE

    By Kampenes, Vigdis

    2007-01-01

    Background: Like any research discipline, software engineering research must be of a certain quality to be valuable. High quality research in software engineering ensures that knowledge is accumulated and helpful advice is given to the industry. One way of assessing research quality is to conduct systematic reviews of the published research literature. Objective: The purpose of this work was to assess the quality of published experiments in software engineering with respect to the validit...

  12. Range of engineering-geological properties for some carbonate rock complexes for Balkan peninsula

    International Nuclear Information System (INIS)

    Jovanovski, Milorad; Shpago, Azra; Peshevski, Igor

    2010-01-01

    The Carbonate Rock masses are a geological media with extremely complex states and properties, which has a certain influences on the mechanical and hydraulic behavior during construction and exploitation of engineering structures. Practical aspects of the problem analysis arise from the fact that the areas of Bosnia and Herzegovina, Macedonia and the entire Balkans is characterized by presence of wide areas covered with carbonate complexes, where large number of complex engineering structures have been, or shall be constructed in the future. In this context, their engineering-geological modeling is still a practical and scientific challenge. The analysis of engineering- geological properties is one of the main steps in forming of analytical and geotechnical models for complex rock structures. This article gives a data about the range for these properties, according to the results from an extensive investigation program. Some original correlations and testing results are given and they are compared with some published relations from the world. (Author)

  13. International Co-Operation in Control Engineering Education Using Online Experiments

    Science.gov (United States)

    Henry, Jim; Schaedel, Herbert M.

    2005-01-01

    This paper describes the international co-operation experience in teaching control engineering with laboratories being conducted remotely by students via the Internet. This paper describes how the students ran the experiments and their personal experiences with the laboratory. A tool for process identification and controller tuning based on…

  14. Two Brief Interventions to Mitigate a "Chilly Climate" Transform Women's Experience, Relationships, and Achievement in Engineering

    Science.gov (United States)

    Walton, Gregory M.; Logel, Christine; Peach, Jennifer M.; Spencer, Steven J.; Zanna, Mark P.

    2015-01-01

    In a randomized-controlled trial, we tested 2 brief interventions designed to mitigate the effects of a "chilly climate" women may experience in engineering, especially in male-dominated fields. Participants were students entering a selective university engineering program. The "social-belonging intervention" aimed to protect…

  15. Understanding the Experience of Women in Undergraduate Engineering Programs at Public Universities

    Science.gov (United States)

    Perez, Jessica Ohanian

    2017-01-01

    Women earn bachelor's degrees in engineering at a rate of less than 17% at public universities in California. The purpose of this study was to understand how women experience undergraduate engineering programs at public universities. To understand this lack of attainment, a qualitative methodology and Feminist Poststructuralist perspective were…

  16. U.S. Adults with Agricultural Experience Report More Genetic Engineering Familiarity than Those Without

    Science.gov (United States)

    Stofer, Kathryn A.; Schiebel, Tracee M.

    2017-01-01

    Researchers and pollsters still debate the acceptance of genetic engineering technology among U.S. adults, and continue to assess their knowledge as part of this research. While decision-making may not rely entirely on knowledge, querying opinions and perceptions rely on public understanding of genetic engineering terms. Experience with…

  17. Foreign Experience in Training Future Engineering Educators for Modeling Technological Processes

    Science.gov (United States)

    Bokhonko, Yevhen

    2017-01-01

    The article deals with the study of foreign experience in training engineering educators for modeling technological processes. It has been stated that engineering education is a field that is being dramatically developed taking into account the occurring changes in educational paradigms, global higher education space, national higher education…

  18. Moral Responsibility, Technology and Experiences of the Tragic: From Kierkegaard to Offshore Engineering.

    NARCIS (Netherlands)

    Coeckelbergh, Mark

    2010-01-01

    The standard response to engineering disasters like the Deepwater Horizon case is to ascribe full moral responsibility to individuals and to collectives treated as individuals. However, this approach is inappropriate since concrete action and experience in engineering contexts seldom meets the

  19. Progreen Online Engineering Diploma in the Middle East: Assessment of the Educational Experience

    Science.gov (United States)

    Baytiyeh, Hoda

    2018-01-01

    Little is known about the status of online learning in the Middle East. This study investigates educational experiences of engineers enrolled in the new joint online ProGreen diploma programme offered by three universities, two in Lebanon and one in Egypt. Forty-eight working engineers responded to an online survey based on the three components of…

  20. Successful Latina Scientists and Engineers: Their Lived Mentoring Experiences and Career Development

    Science.gov (United States)

    San Miguel, Anitza M.; Kim, Mikyong Minsun

    2015-01-01

    Utilizing a phenomenological perspective and method, this study aimed to reveal the lived career mentoring experiences of Latinas in science and engineering and to understand how selected Latina scientists and engineers achieved high-level positions. Our in-depth interviews revealed that (a) it is important to have multiple mentors for Latinas'…

  1. Investigation of Students' Experiences of Gendered Cultures in Engineering Workplaces

    Science.gov (United States)

    Male, Sally A.; Gardner, Anne; Figueroa, Eugenia; Bennett, Dawn

    2018-01-01

    Women remain severely under-represented in engineering in Australia as in all Western countries. This limits the pool of talent, standpoints and approaches within the profession. Furthermore, this under-representation equates to restriction of the benefits of being an engineer mainly to men. Gendered workplace experiences have been found to…

  2. Recycled aggregates in concrete production: engineering properties and environmental impact

    OpenAIRE

    Seddik Meddah Mohammed

    2017-01-01

    Recycled concrete aggregate is considered as the most abundant and used secondary aggregate in concrete production, other types of solid waste are also being used in concrete for specific purposes and to achieve some desired properties. Recycled aggregates and particularly, recycled concrete aggregate substantially affect the properties and mix design of concrete both at fresh and hardened states since it is known by high porosity due to the adhered layer of old mortar on the aggregate which ...

  3. BC Hydro experiences the power of engineering document management software

    International Nuclear Information System (INIS)

    Wilkins, A.

    2000-01-01

    The recent popularity of electronic document management software (EDMS), specifically designed for engineering CAD/CAM drawings that holds the promise of reducing paper-pushing and freeing up organizational resources for more productive purposes, is discussed. To illustrate how such systems function, a document management system installed at BC Hydro, with over 2,500 users in two main engineering groups is described. The new system - FileNET - replaces several older systems that have been used as stand-alone systems in various divisions of BC Hydro for some time. Instead of integrating the entire file of some 750,000 documents, the new system has complete records of some 70,000 of the most recent CAD drawings and an on-line index to the older file that is used less frequently. Access to the entire storehouse of drawings is said to be fast, efficient and secure. Automated document control procedures during work-in-progress, viewing, redlining capabilities, seamless integration with CAD tools and Web access to drawings from anywhere within the two engineering divisions, are some of the most noteworthy characteristics of the new system. It does not completely replace paper, but it does promise significant streamlining of the paper handling function. It also ensures that BC Hydro's central computer is the prime repository of all documents and drawings, and that this valuable record of environmental. legal, regulatory and other public policy importance is instantly available, without the need to handle paper

  4. Foundations for value education in engineering: the Indian experience.

    Science.gov (United States)

    Gupta, Amitabha

    2015-04-01

    The objective of this paper is to discuss some of the foundational issues centering around the question of integrating education in human values with professional engineering education: its necessity and justification. The paper looks at the efforts in 'tuning' the technical education system in India to the national goals in the various phases of curriculum development. The contribution of the engineering profession in national development and India's self-sufficiency is crucially linked with the institutionalization of expertise and the role of morality and responsibility. This linkage can be created through a proper understanding of the social role of the profession-what motivates the professionals and what makes professional life meaningful. Value education facilitates the process of moral maturity and the development of a 'holistic' mindset. This paper deals with the need to create such a mindset, the human values associated with it and gives examples of efforts to impart such education through 'action-oriented' programmes introduced in some institutes of engineering in India.

  5. A Modular Artificial Intelligence Inference Engine System (MAIS) for support of on orbit experiments

    Science.gov (United States)

    Hancock, Thomas M., III

    1994-01-01

    This paper describes a Modular Artificial Intelligence Inference Engine System (MAIS) support tool that would provide health and status monitoring, cognitive replanning, analysis and support of on-orbit Space Station, Spacelab experiments and systems.

  6. A study experiment of auto idle application in the excavator engine performance

    Energy Technology Data Exchange (ETDEWEB)

    Purwanto, Wawan, E-mail: wawan5527@gmail.com; Maksum, Hasan; Putra, Dwi Sudarno, E-mail: dwisudarnoputra@ft.unp.ac.id; Wahyudi, Retno [State University of Padang, West Sumatera (Indonesia); Azmi, Meri, E-mail: meriazmi@gmail.com [State Polytechnic of Padang, West Sumatera (Indonesia)

    2016-03-29

    The purpose of this study was to analyze the effect of applying auto idle to excavator engine performance, such as machine unitization and fuel consumption in Excavator. Steps to be done are to modify the system JA 44 and 67 in Vehicle Electronic Control Unit (V-ECU). The modifications will be obtained from the pattern of the engine speed. If the excavator attachment is not operated, the engine speed will return to the idle speed automatically. From the experiment results the auto idle reduces fuel consumption in excavator engine.

  7. Some statistical properties of strange attractors: engineering view

    International Nuclear Information System (INIS)

    Mijangos, M; Kontorovich, V; Aguilar-Torrentera, J

    2008-01-01

    In this paper, the statistical characterization of strange attractors is investigated via the so-called 'model distribution' approach. It is shown that in order to calculate the first four cumulants, which are necessary to create a model distribution of kurtosis approximation, a systematic method for the calculus of the variance needs to be considered. Correspondently, an analytical method based on the Kolmogorov-Sinai (K-S) entropy for variance approximation is herein proposed. The methodology is of interest for its application in the statistical analysis of chaotic systems that model physical phenomena found in some areas of electrical (communication) engineering

  8. Experiences of girls in a fabrication engineering environment

    CSIR Research Space (South Africa)

    Dlodlo, N

    2009-01-01

    Full Text Available % Mathematical and statistical sciences 6,903 9,505 42 % Biological sciences 11,951 11,831 50 % Physical and chemical sciences 4,575 10,050 31 % Engineering 1,467 30,897 5 % Source: Department of Science and Technology, 2009b. NOT FOR COMMERCIAL US E 130... that the introductory phase of the activities which consisted of explaining to the students was diffi cult to understand. Their eyes were opened when they started implementing the practical aspects. In the Fab Kids lab, the learners are introduced to theory...

  9. Some engineering properties of white kidney beans (Phaseolus ...

    African Journals Online (AJOL)

    ajl yemi

    2011-12-19

    Dec 19, 2011 ... ... (physical and mechanical) properties, white kidney beans, moisture content, thousand grain mass, static coefficient of friction. INTRODUCTION. White kidney beans (Phaseolus vulgaris L.) are a culti- vated plant grown for fresh and dry consumption and a common raw material in the canned food industry.

  10. Recycled aggregates in concrete production: engineering properties and environmental impact

    Directory of Open Access Journals (Sweden)

    Seddik Meddah Mohammed

    2017-01-01

    Full Text Available Recycled concrete aggregate is considered as the most abundant and used secondary aggregate in concrete production, other types of solid waste are also being used in concrete for specific purposes and to achieve some desired properties. Recycled aggregates and particularly, recycled concrete aggregate substantially affect the properties and mix design of concrete both at fresh and hardened states since it is known by high porosity due to the adhered layer of old mortar on the aggregate which results in a high water absorption of the recycled secondary aggregate. This leads to lower density and strength, and other durability related properties. The use of most recycled aggregate in concrete structures is still limited to low strength and non-structural applications due to important drop in strength and durability performances generated. Embedding recycled aggregates in concrete is now a current practice in many countries to enhance sustainability of concrete industry and reduce its environmental impacts. The present paper discusses the various possible recycled aggregates used in concrete production, their effect on both fresh and hardened properties as well as durability performances. The economic and environmental impacts of partially or fully substituting natural aggregates by secondary recycled aggregates are also discussed.

  11. Closing the loop on improvement: Packaging experience in the Software Engineering Laboratory

    Science.gov (United States)

    Waligora, Sharon R.; Landis, Linda C.; Doland, Jerry T.

    1994-01-01

    As part of its award-winning software process improvement program, the Software Engineering Laboratory (SEL) has developed an effective method for packaging organizational best practices based on real project experience into useful handbooks and training courses. This paper shares the SEL's experience over the past 12 years creating and updating software process handbooks and training courses. It provides cost models and guidelines for successful experience packaging derived from SEL experience.

  12. Engineering Status of the Fusion Ignition Research Experiment (FIRE)

    International Nuclear Information System (INIS)

    Heitzenroeder, Philip J.; Meade, Dale; Thome, Richard J.

    2000-01-01

    FIRE is a compact, high field tokamak being studied as an option for the next step in the US magnetic fusion energy program. FIRE's programmatic mission is to attain, explore, understand, and optimize alpha-dominated plasmas to provide the knowledge necessary for the design of attractive magnetic fusion energy systems. This study began in 1999 with broad participation of the US fusion community, including several industrial participants. The design under development has a major radius of 2 m, a minor radius of 0.525 m, a field on axis of 10T and capability to operate at 12T with upgrades to power supplies. Toroidal and poloidal field magnets are inertially cooled with liquid nitrogen. An important goal for FIRE is a total project cost in the $1B range. This paper presents an overview of the engineering details which were developed during the FIRE preconceptual design study in FY99 and 00

  13. Engineering test station for TFTR blanket module experiments

    International Nuclear Information System (INIS)

    Jassby, D.L.; Leinoff, S.

    1979-12-01

    A conceptual design has been carried out for an Engineering Test Station (ETS) which will provide structural support and utilities/instrumentation services for blanket modules positioned adjacent to the vacuum vessel of the TFTR (Tokamak Fusion Test Reactor). The ETS is supported independently from the Test Cell floor. The ETS module support platform is constructed of fiberglass to eliminate electromagnetic interaction with the pulsed tokamak fields. The ETS can hold blanket modules with dimensions up to 78 cm in width, 85 cm in height, and 105 cm in depth, and with a weight up to 4000 kg. Interfaces for all utility and instrumentation requirements are made via a shield plug in the TFTR igloo shielding. The modules are readily installed or removed by means of TFTR remote handling equipment

  14. Chemical engineering in fuel reprocessing. The French experience

    International Nuclear Information System (INIS)

    Viala, M.; Sombret, C.; Bernard, C.; Miquel, P.; Moulin, J.P.

    1992-01-01

    Reprocessing is the back-end of the nuclear fuel cycle, designed to recover valuable fissile materials, especially plutonium, and to condition safely all the wastes ready for disposal. For its new commercial reprocessing plants (UP 3 and UP 2 800) COGEMA decided to include many engineering innovations as well as new processes and key-components developed by CEA. UP 3 is a complete new plant with a capacity of 800 t/y which was put in operation in August 1990. UP 2 800 is an extension of the existing UP 2 facility, designed to achieve the same annual capacity of 800 t/y, to be put in operation at the end of 1993 by the commissioning of a new head-end and highly active chemical process facilities

  15. A thermodynamic approach to obtain materials properties for engineering applications

    Science.gov (United States)

    Chang, Y. Austin

    1993-01-01

    With the ever increases in the capabilities of computers for numerical computations, we are on the verge of using these tools to model manufacturing processes for improving the efficiency of these processes as well as the quality of the products. One such process is casting for the production of metals. However, in order to model metal casting processes in a meaningful way it is essential to have the basic properties of these materials in their molten state, solid state as well as in the mixed state of solid and liquid. Some of the properties needed may be considered as intrinsic such as the density, heat capacity or enthalpy of freezing of a pure metal, while others are not. For instance, the enthalpy of solidification of an alloy is not a defined thermodynamic quantity. Its value depends on the micro-segregation of the phases during the course of solidification. The objective of the present study is to present a thermodynamic approach to obtain some of the intrinsic properties and combining thermodynamics with kinetic models to estimate such quantities as the enthalpy of solidification of an alloy.

  16. Software engineering and data management for automated payload experiment tool

    Science.gov (United States)

    Maddux, Gary A.; Provancha, Anna; Chattam, David

    1994-01-01

    The Microgravity Projects Office identified a need to develop a software package that will lead experiment developers through the development planning process, obtain necessary information, establish an electronic data exchange avenue, and allow easier manipulation/reformatting of the collected information. An MS-DOS compatible software package called the Automated Payload Experiment Tool (APET) has been developed and delivered. The objective of this task is to expand on the results of the APET work previously performed by University of Alabama in Huntsville (UAH) and provide versions of the software in a Macintosh and Windows compatible format. Appendix 1 science requirements document (SRD) Users Manual is attached.

  17. Multiple case study analysis of young women's experiences in high school engineering

    Science.gov (United States)

    Pollock, Meagan C.

    At a time when engineers are in critical demand, women continue to be significantly underrepresented in engineering fields (11.7%) and degree programs (21.3%) in the United States. As a result, there is a national demand for improved K-12 STEM education and targeted efforts to improve equity and access to engineering and science careers for every underrepresented group. High school engineering has become a nascent and growing market for developers and an emergent opportunity for students across the United States to learn introductory engineering skills through strategic career pathways; however there is a disparity in participation at this level as well. Much useful research has been used to examine the problematization of underrepresentation (K Beddoes, 2011), but there is a dearth of literature that helps us to understand the experiences of young women in high school engineering. By examining the experiences of young women in high school engineering, we can learn ways to improve the curriculum, pedagogy, and environment for underrepresented groups such as females to ensure they have equitable access to these programs and are subsequently motivated to persist in engineering. Understanding the needs of marginalized groups is complex, and intersectional feminism seeks to understand gender in relation to other identities such as race, class, ethnicity, sexuality, and nationality. This theory asserts that gender alone is neither a total identity nor a universal experience, and it is thus advantageous to consider each of the intersecting layers of identity so as to not privilege a dominate group as representative of all women. Thus, to understand how female students engage with and experience engineering in grade school, it is useful to examine through the lens of gender, class, race, and sexuality, because this intersection frames much of the human experience. The purpose of this study is to examine high school females' experiences in engineering, with a goal to

  18. Some engineering properties of white kidney beans (Phaseolus ...

    African Journals Online (AJOL)

    ajl yemi

    2011-12-19

    Dec 19, 2011 ... projected area from 128.13 to 198.83 mm2, the true density from 1128.05 to 1290.85 kgm-3, the .... The white kidney bean grains used in the study were obtained from .... For each experiment, a sample was dropped into the.

  19. Enhancing the Student Learning Experience in Software Engineering Project Courses

    Science.gov (United States)

    Marques, Maira; Ochoa, Sergio F.; Bastarrica, Maria Cecilia; Gutierrez, Francisco J.

    2018-01-01

    Carrying out real-world software projects in their academic studies helps students to understand what they will face in industry, and to experience first-hand the challenges involved when working collaboratively. Most of the instructional strategies used to help students take advantage of these activities focus on supporting agile programming,…

  20. On Design Experiment Teaching in Engineering Quality Cultivation

    Science.gov (United States)

    Chen, Xiao

    2008-01-01

    Design experiment refers to that designed and conducted by students independently and is surely an important method to cultivate students' comprehensive quality. According to the development and requirements of experimental teaching, this article carries out a study and analysis on the purpose, significance, denotation, connotation and…

  1. A Gamification Experience to Improve Engineering Students' Performance through Motivation

    Science.gov (United States)

    Sánchez-Carmona, Adrián; Robles, Sergi; Pons, Jordi

    2017-01-01

    The students' lack of motivation is a usual problem. The students value more the obtention of the degree than the developing of competences and skills. In order to fight this, we developed a gamification's experience based on merits and leaderboards. The merits are linked to the attainment of skills and competences that students usually do not…

  2. High temperature engineering research facilities and experiments in Russia

    International Nuclear Information System (INIS)

    Kodochigov, N.G.; Kuzavkov, N.G.; Sukharev, Y.P.; Chudin, A.G.

    1998-01-01

    An overview is given of the characteristics of the experimental facilities and experiments in the Russian Federation: the HTGR neutron-physical investigation facilities ASTRA and GROG; facilities for fuel, graphite and other elements irradiation; and thermal hydraulics experimental facilities. The overview is presented in the form of copies of overhead sheets

  3. Kuwaiti engineers' perspectives of the engineering senior design (Capstone) course as related to their professional experiences

    Science.gov (United States)

    Alsagheer, Abdullah

    This study looks into transfer of learning and its application in the actual employment of engineering students after graduation. At Kuwait University, a capstone course is being offered that aims to ensure that students amalgamate all kinds of engineering skills to apply to their work. Within a basic interpretive, qualitative study-design methodology, I interviewed 12 engineers who have recently experienced the senior design course at Kuwait University and are presently working in industry. From the analysis, four basic themes emerged that further delineate the focus of the entire study. The themes are 1) need for the capstone course, 2) applicability of and problems with the capstone course, 3) industry problems with training, and 4) students' attitudes toward the capstone course. The study concludes that participants are not transferring engineering skills; rather, they are transferring all types of instructions they have been given during their course of study at the university. A frequent statement is that the capstone course should be improved and specifically that it is necessary to improve upon the timing, schedule, teachers' behavior, contents, and format. The study concludes that Kuwaiti engineers on the whole face problems with time management and management support. The study includes some implications for Kuwait University and recommendations that can provide significant support for the development of the Senior Design (Capstone) Course. For examples: the project must be divided into phases to ensure timely completion of deliverables. In order to motivate students for hard work and to achieve true transfer of learning, Kuwait University is required to communicate with certain organizations to place its students at their research centers for capstone projects. All universities, including Kuwait University, should hire faculty specifically to run the capstone course. In conclusion, the study includes some suggestions for further research studies focused

  4. Rational engineering of physicochemical properties of nanomaterials for biomedical applications with nanotoxicological perspectives.

    Science.gov (United States)

    Navya, P N; Daima, Hemant Kumar

    2016-01-01

    Innovative engineered nanomaterials are at the leading edge of rapidly emerging fields of nanobiotechnology and nanomedicine. Meticulous synthesis, unique physicochemical properties, manifestation of chemical or biological moieties on the surface of materials make engineered nanostructures suitable for a variety of biomedical applications. Besides, tailored nanomaterials exhibit entirely novel therapeutic applications with better functionality, sensitivity, efficiency and specificity due to their customized unique physicochemical and surface properties. Additionally, such designer made nanomaterials has potential to generate series of interactions with various biological entities including DNA, proteins, membranes, cells and organelles at nano-bio interface. These nano-bio interactions are driven by colloidal forces and predominantly depend on the dynamic physicochemical and surface properties of nanomaterials. Nevertheless, recent development and atomic scale tailoring of various physical, chemical and surface properties of nanomaterials is promising to dictate their interaction in anticipated manner with biological entities for biomedical applications. As a result, rationally designed nanomaterials are in extensive demand for bio-molecular detection and diagnostics, therapeutics, drug and gene delivery, fluorescent labelling, tissue engineering, biochemical sensing and other pharmaceuticals applications. However, toxicity and risk associated with engineered nanomaterials is rather unclear or not well understood; which is gaining considerable attention and the field of nanotoxicology is evolving promptly. Therefore, this review explores current knowledge of articulate engineering of nanomaterials for biomedical applications with special attention on potential toxicological perspectives.

  5. Engineering Database of Liquid Salt Thermophysical and Thermochemical Properties

    Energy Technology Data Exchange (ETDEWEB)

    Manohar S. Sohal; Matthias A. Ebner; Piyush Sabharwall; Phil Sharpe

    2010-03-01

    The purpose of this report is to provide a review of thermodynamic and thermophysical properties of candidate molten salt coolants, which may be used as a primary coolant within a nuclear reactor or heat transport medium from the Next Generation Nuclear Plant (NGNP) to a processing plant, for example, a hydrogen-production plant. Thermodynamic properties of four types of molten salts, including LiF-BeF2 (67 and 33 mol%, respectively; also known as FLiBe), LiF-NaF-KF (46.5, 11.5, and 52 mol%, also known as FLiNaK), and KCl-MgCl2 (67 and 33 mol%), and sodium nitrate-sodium nitrite-potassium nitrate (NaNO3–NaNO2–KNO3, (7-49-44 or 7-40-53 mol%) have been investigated. Limitations of existing correlations to predict density, viscosity, specific heat capacity, surface tension, and thermal conductivity, were identified. The impact of thermodynamic properties on the heat transfer, especially Nusselt number was also discussed. Stability of the molten salts with structural alloys and their compatibility with the structural alloys was studied. Nickel and alloys with dense Ni coatings are effectively inert to corrosion in fluorides but not so in chlorides. Of the chromium containing alloys, Hastelloy N appears to have the best corrosion resistance in fluorides, while Haynes 230 was most resistant in chloride. In general, alloys with increasing carbon and chromium content are increasingly subject to corrosion by the fluoride salts FLiBe and FLiNaK, due to attack and dissolution of the intergranular chromium carbide. Future research to obtain needed information was identified.

  6. Software Engineering Researchers' Attitudes on Case Studies and Experiments : an Exploratory Survey

    NARCIS (Netherlands)

    Tofan, Dan; Galster, Matthias; Avgeriou, Paris; Weyns, Danny

    2011-01-01

    Background: Case studies and experiments are research methods frequently applied in empirical software engineering. Experiments are well-­understood and their value as an empirical method is recognized. On the other hand, there seem to be different opinions on what constitutes a case study, and

  7. Optimal Design of Experiments for Parametric Identification of Civil Engineering Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning

    Optimal Systems of experiments for parametric identification of civil engineering structures is investigated. Design of experiments for parametric identification of dynamic systems is usually done by minimizing a scalar measure, e.g the determinant, the trace ect., of an estimated parameter...

  8. A business process modeling experience in a complex information system re-engineering.

    Science.gov (United States)

    Bernonville, Stéphanie; Vantourout, Corinne; Fendeler, Geneviève; Beuscart, Régis

    2013-01-01

    This article aims to share a business process modeling experience in a re-engineering project of a medical records department in a 2,965-bed hospital. It presents the modeling strategy, an extract of the results and the feedback experience.

  9. The Characteristics and Experiences of Successful Undergraduate Latina Students Who Persist in Engineering

    Science.gov (United States)

    Robinson, Carrie

    Females and underrepresented ethnic minorities earn a small percentage of engineering and computer science bachelor's degrees awarded in the United States, earn an even smaller proportion of master's and doctoral degrees, and are underrepresented in the engineering workforce (Engineering Workforce Commission, [2006], as cited in National Science Foundation, 2012; United States Department of Education, [2006], as cited in National Science Foundation, 2009a; United States Department of Education, [2006], as cited in National Science Foundation, 2009b). Considerable research has examined the perceptions, culture, curriculum, and pedagogy in engineering that inhibits the achievement of women and underrepresented ethnic minorities. This action research study used a qualitative approach to examine the characteristics and experiences of Latina students who pursued a bachelor's degree in the Ira A. Fulton Schools of Engineering at Arizona State University (ASU) as part of the 2008 first-time full-time freshman cohort. The researcher conducted two semi-structured individual interviews with seven undergraduate Latina students who successfully persisted to their fourth (senior) year in engineering. The researcher aimed to understand what characteristics made these students successful and how their experiences affected their persistence in an engineering major. The data collected showed that the Latina participants were motivated to persist in their engineering degree program due to their parents' expectations for success and high academic achievement; their desire to overcome the discrimination, stereotyping, and naysayers that they encountered; and their aspiration to become a role model for their family and other students interested in pursuing engineering. From the data collected, the researcher provided suggestions to implement and adapt educational activities and support systems within the Ira A. Fulton Schools of Engineering to improve the retention and graduation rates

  10. Rocket Engine Turbine Blade Surface Pressure Distributions Experiment and Computations

    Science.gov (United States)

    Hudson, Susan T.; Zoladz, Thomas F.; Dorney, Daniel J.; Turner, James (Technical Monitor)

    2002-01-01

    Understanding the unsteady aspects of turbine rotor flow fields is critical to successful future turbine designs. A technology program was conducted at NASA's Marshall Space Flight Center to increase the understanding of unsteady environments for rocket engine turbines. The experimental program involved instrumenting turbine rotor blades with miniature surface mounted high frequency response pressure transducers. The turbine model was then tested to measure the unsteady pressures on the rotor blades. The data obtained from the experimental program is unique in two respects. First, much more unsteady data was obtained (several minutes per set point) than has been possible in the past. Also, an extensive steady performance database existed for the turbine model. This allowed an evaluation of the effect of the on-blade instrumentation on the turbine's performance. A three-dimensional unsteady Navier-Stokes analysis was also used to blindly predict the unsteady flow field in the turbine at the design operating conditions and at +15 degrees relative incidence to the first-stage rotor. The predicted time-averaged and unsteady pressure distributions show good agreement with the experimental data. This unique data set, the lessons learned for acquiring this type of data, and the improvements made to the data analysis and prediction tools are contributing significantly to current Space Launch Initiative turbine airflow test and blade surface pressure prediction efforts.

  11. SGN's Dismantling and Decommissioning engineering, projects experience and capabilities

    International Nuclear Information System (INIS)

    Destrait, L.

    1998-01-01

    Its experience in waste treatment, conditioning, storage and disposal, its cooperation with CEA and COGEMA Group in license agreements give SGN expertise in the decommissioning field. SGN's experience and background in all areas of nuclear facility decommissioning, such as chemical and mechanical cells, nuclear advanced reactors, reprocessing facilities result in fruitful references to the customers. The poster is presenting different achievements and projects with SGN's participation such as: - The decommissioning of Windscale Advanced Gas cooled Reactors (WAGR), in particular providing methodology and equipment to dismantle the Pressure and Insulation Vessel of the reactor. - The decommissioning plan of Ignalina (Lithuania) and Paldiski (Estonia), defining strategies, scenarios, necessary equipments and tools and choosing the best solutions to decommission the site under different influencing parameters such as cost, dose rate exposure, etc... - Th One Site Assistance Team (OSAT) at Chernobyl regarding the preparation works for the waste management and decommissioning of the plant. - The decommissioning of French nuclear facilities such as reprocessing (UP1) and reactor (EL4) plants. The important experience acquired during the facility management and during the first dismantling and decommissioning operations is an important factor for the smooth running of these techniques for the future. The challenge to come is to control all the operations, the choice of strategies, the waste management, the efficiency of tools and equipments, and to provide nuclear operators with a full range of proven techniques to optimise costs and minimize decommissioning personnel exposure. (Author)

  12. Identification and quantification analysis of nonlinear dynamics properties of combustion instability in a diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Li-Ping, E-mail: yangliping302@hrbeu.edu.cn; Ding, Shun-Liang; Song, En-Zhe; Ma, Xiu-Zhen [Institute of Power and Energy Engineering, Harbin Engineering University, No. 145-1, Nantong Street, Nangang District, Harbin 150001 (China); Litak, Grzegorz [Faculty of Mechanical Engineering, Lublin University of Technology, Nadbystrzycka 36, 20-618 Lublin (Poland)

    2015-01-15

    The cycling combustion instabilities in a diesel engine have been analyzed based on chaos theory. The objective was to investigate the dynamical characteristics of combustion in diesel engine. In this study, experiments were performed under the entire operating range of a diesel engine (the engine speed was changed from 600 to 1400 rpm and the engine load rate was from 0% to 100%), and acquired real-time series of in-cylinder combustion pressure using a piezoelectric transducer installed on the cylinder head. Several methods were applied to identify and quantitatively analyze the combustion process complexity in the diesel engine including delay-coordinate embedding, recurrence plot (RP), Recurrence Quantification Analysis, correlation dimension (CD), and the largest Lyapunov exponent (LLE) estimation. The results show that the combustion process exhibits some determinism. If LLE is positive, then the combustion system has a fractal dimension and CD is no more than 1.6 and within the diesel engine operating range. We have concluded that the combustion system of diesel engine is a low-dimensional chaotic system and the maximum values of CD and LLE occur at the lowest engine speed and load. This means that combustion system is more complex and sensitive to initial conditions and that poor combustion quality leads to the decrease of fuel economy and the increase of exhaust emissions.

  13. Identification and quantification analysis of nonlinear dynamics properties of combustion instability in a diesel engine.

    Science.gov (United States)

    Yang, Li-Ping; Ding, Shun-Liang; Litak, Grzegorz; Song, En-Zhe; Ma, Xiu-Zhen

    2015-01-01

    The cycling combustion instabilities in a diesel engine have been analyzed based on chaos theory. The objective was to investigate the dynamical characteristics of combustion in diesel engine. In this study, experiments were performed under the entire operating range of a diesel engine (the engine speed was changed from 600 to 1400 rpm and the engine load rate was from 0% to 100%), and acquired real-time series of in-cylinder combustion pressure using a piezoelectric transducer installed on the cylinder head. Several methods were applied to identify and quantitatively analyze the combustion process complexity in the diesel engine including delay-coordinate embedding, recurrence plot (RP), Recurrence Quantification Analysis, correlation dimension (CD), and the largest Lyapunov exponent (LLE) estimation. The results show that the combustion process exhibits some determinism. If LLE is positive, then the combustion system has a fractal dimension and CD is no more than 1.6 and within the diesel engine operating range. We have concluded that the combustion system of diesel engine is a low-dimensional chaotic system and the maximum values of CD and LLE occur at the lowest engine speed and load. This means that combustion system is more complex and sensitive to initial conditions and that poor combustion quality leads to the decrease of fuel economy and the increase of exhaust emissions.

  14. Identification and quantification analysis of nonlinear dynamics properties of combustion instability in a diesel engine

    International Nuclear Information System (INIS)

    Yang, Li-Ping; Ding, Shun-Liang; Song, En-Zhe; Ma, Xiu-Zhen; Litak, Grzegorz

    2015-01-01

    The cycling combustion instabilities in a diesel engine have been analyzed based on chaos theory. The objective was to investigate the dynamical characteristics of combustion in diesel engine. In this study, experiments were performed under the entire operating range of a diesel engine (the engine speed was changed from 600 to 1400 rpm and the engine load rate was from 0% to 100%), and acquired real-time series of in-cylinder combustion pressure using a piezoelectric transducer installed on the cylinder head. Several methods were applied to identify and quantitatively analyze the combustion process complexity in the diesel engine including delay-coordinate embedding, recurrence plot (RP), Recurrence Quantification Analysis, correlation dimension (CD), and the largest Lyapunov exponent (LLE) estimation. The results show that the combustion process exhibits some determinism. If LLE is positive, then the combustion system has a fractal dimension and CD is no more than 1.6 and within the diesel engine operating range. We have concluded that the combustion system of diesel engine is a low-dimensional chaotic system and the maximum values of CD and LLE occur at the lowest engine speed and load. This means that combustion system is more complex and sensitive to initial conditions and that poor combustion quality leads to the decrease of fuel economy and the increase of exhaust emissions

  15. Local mechanical properties of LFT injection molded parts: Numerical simulations versus experiments

    Science.gov (United States)

    Desplentere, F.; Soete, K.; Bonte, H.; Debrabandere, E.

    2014-05-01

    In predictive engineering for polymer processes, the proper prediction of material microstructure from known processing conditions and constituent material properties is a critical step forward properly predicting bulk properties in the finished composite. Operating within the context of long-fiber thermoplastics (LFT, length Autodesk Simulation Moldflow Insight 2014 software has been used. In this software, a fiber breakage algorithm for the polymer flow inside the mold is available. Using well known micro mechanic formulas allow to combine the local fiber length with the local orientation into local mechanical properties. Different experiments were performed using a commercially available glass fiber filled compound to compare the measured data with the numerical simulation results. In this investigation, tensile tests and 3 point bending tests are considered. To characterize the fiber length distribution of the polymer melt entering the mold (necessary for the numerical simulations), air shots were performed. For those air shots, similar homogenization conditions were used as during the injection molding tests. The fiber length distribution is characterized using automated optical method on samples for which the matrix material is burned away. Using the appropriate settings for the different experiments, good predictions of the local mechanical properties are obtained.

  16. Preparation and biological properties of a novel composite scaffold of nano-hydroxyapatite/chitosan/carboxymethyl cellulose for bone tissue engineering

    Directory of Open Access Journals (Sweden)

    Chengdong Xiong

    2009-07-01

    Full Text Available Abstract In this study, we report the physico-chemical and biological properties of a novel biodegradable composite scaffold made of nano-hydroxyapatite and natural derived polymers of chitosan and carboxymethyl cellulose, namely, n-HA/CS/CMC, which was prepared by freeze-drying method. The physico-chemical properties of n-HA/CS/CMC scaffold were tested by infrared absorption spectra (IR, transmission electron microscope(TEM, scanning electron microscope(SEM, universal material testing machine and phosphate buffer solution (PBS soaking experiment. Besides, the biological properties were evaluated by MG63 cells and Mesenchymal stem cells (MSCs culture experiment in vitro and a short period implantation study in vivo. The results show that the composite scaffold is mainly formed through the ionic crossing-linking of the two polyions between CS and CMC, and n-HA is incorporated into the polyelectrolyte matrix of CS-CMC without agglomeration, which endows the scaffold with good physico-chemical properties such as highly interconnected porous structure, high compressive strength and good structural stability and degradation. More important, the results of cells attached, proliferated on the scaffold indicate that the scaffold is non-toxic and has good cell biocompatibility, and the results of implantation experiment in vivo further confirm that the scaffold has good tissue biocompatibility. All the above results suggest that the novel degradable n-HA/CS/CMC composite scaffold has a great potential to be used as bone tissue engineering material.

  17. Preparation and biological properties of a novel composite scaffold of nano-hydroxyapatite/chitosan/carboxymethyl cellulose for bone tissue engineering

    Science.gov (United States)

    Liuyun, Jiang; Yubao, Li; Chengdong, Xiong

    2009-01-01

    In this study, we report the physico-chemical and biological properties of a novel biodegradable composite scaffold made of nano-hydroxyapatite and natural derived polymers of chitosan and carboxymethyl cellulose, namely, n-HA/CS/CMC, which was prepared by freeze-drying method. The physico-chemical properties of n-HA/CS/CMC scaffold were tested by infrared absorption spectra (IR), transmission electron microscope(TEM), scanning electron microscope(SEM), universal material testing machine and phosphate buffer solution (PBS) soaking experiment. Besides, the biological properties were evaluated by MG63 cells and Mesenchymal stem cells (MSCs) culture experiment in vitro and a short period implantation study in vivo. The results show that the composite scaffold is mainly formed through the ionic crossing-linking of the two polyions between CS and CMC, and n-HA is incorporated into the polyelectrolyte matrix of CS-CMC without agglomeration, which endows the scaffold with good physico-chemical properties such as highly interconnected porous structure, high compressive strength and good structural stability and degradation. More important, the results of cells attached, proliferated on the scaffold indicate that the scaffold is non-toxic and has good cell biocompatibility, and the results of implantation experiment in vivo further confirm that the scaffold has good tissue biocompatibility. All the above results suggest that the novel degradable n-HA/CS/CMC composite scaffold has a great potential to be used as bone tissue engineering material. PMID:19594953

  18. Experiences with project-oriented research in graduate engineering education

    International Nuclear Information System (INIS)

    Miley, G.H.

    1976-01-01

    Two examples of project-oriented research that involve the conceptual design of fusion systems are described. One of these projects involved close collaboration with workers in a national laboratory while the second was formally organized as a cooperative effort with two other laboratories. An important educational aspect of such research is that the students are involved in a design team composed of both students and professionals facing a realistic problem. In retrospect, it appears that both students and faculty profited from the experience. Several students have taken jobs in related areas, and additional research has resulted at the University from new insight gained during the projects

  19. The engineering design of the Tokamak Physics Experiment

    International Nuclear Information System (INIS)

    Schmidt, J.A.

    1994-01-01

    A mission and supporting physics objectives have been developed, which establishes an important role for the Tokamak Physics Experiment (TPX) in developing the physic basis for a future fusion reactor. The design of TPX include advanced physics features, such as shaping and profile control, along with the capability of operating for very long pulses. The development of the superconducting magnets, actively cooled internal hardware, and remote maintenance will be an important technology contribution to future fusion projects, such as ITER. The Conceptual Design and Management Systems for TPX have been developed and reviewed, and the project is beginning Preliminary Design. If adequately funded the construction project should be completed in the year 2000

  20. Optimization of Biodiesel-Diesel Blended Fuel Properties and Engine Performance with Ether Additive Using Statistical Analysis and Response Surface Methods

    Directory of Open Access Journals (Sweden)

    Obed M. Ali

    2015-12-01

    Full Text Available In this study, the fuel properties and engine performance of blended palm biodiesel-diesel using diethyl ether as additive have been investigated. The properties of B30 blended palm biodiesel-diesel fuel were measured and analyzed statistically with the addition of 2%, 4%, 6% and 8% (by volume diethyl ether additive. The engine tests were conducted at increasing engine speeds from 1500 rpm to 3500 rpm and under constant load. Optimization of independent variables was performed using the desirability approach of the response surface methodology (RSM with the goal of minimizing emissions and maximizing performance parameters. The experiments were designed using a statistical tool known as design of experiments (DoE based on RSM.

  1. SSSFD manipulator engineering using statistical experiment design techniques

    Science.gov (United States)

    Barnes, John

    1991-01-01

    The Satellite Servicer System Flight Demonstration (SSSFD) program is a series of Shuttle flights designed to verify major on-orbit satellite servicing capabilities, such as rendezvous and docking of free flyers, Orbital Replacement Unit (ORU) exchange, and fluid transfer. A major part of this system is the manipulator system that will perform the ORU exchange. The manipulator must possess adequate toolplate dexterity to maneuver a variety of EVA-type tools into position to interface with ORU fasteners, connectors, latches, and handles on the satellite, and to move workpieces and ORUs through 6 degree of freedom (dof) space from the Target Vehicle (TV) to the Support Module (SM) and back. Two cost efficient tools were combined to perform a study of robot manipulator design parameters. These tools are graphical computer simulations and Taguchi Design of Experiment methods. Using a graphics platform, an off-the-shelf robot simulation software package, and an experiment designed with Taguchi's approach, the sensitivities of various manipulator kinematic design parameters to performance characteristics are determined with minimal cost.

  2. Engineering experiences through nuclear power development in Japan

    International Nuclear Information System (INIS)

    Uchida, Hideo

    2004-01-01

    This keynote paper deals with: energy issues and nuclear power development in Japan, problems of radiation protection, licensing and safety regulations, research on LOCA and ECCS, stress corrosion cracks related to pressure vessels, nuclear fuel failures, steam generators, incidents, waste management and fuel cycle facilities. In conclusion it is stated that: on order to cope with global matters vitally affecting the electricity generation, taking into consideration Japanese specific energy issues, the nuclear power development has been an indispensable policy of Japan. In order to proceed with further development of nuclear power plants, it is necessary to obtain proper understanding by the public, showing assurance of the safety and reliable operation of nuclear power plants through daily plant operation. The nuclear safety issues should be considered from a global point of view. It is necessary to establish common safety standards which could harmonize the safety level of nuclear power plants in the world. The safety goal concerning severe accidents should be established as an internationally agreeable one. Japan has accumulated highly technological experience in maintenance of nuclear power plants. It is believed that the cumulative experiences in Japan can contribute to the further improvement of safety of nuclear power plants throughout the world, and for this aim a mutual information exchange should be encouraged

  3. Implementing an integrated engineering data base system: A developer's experience and the application to IPAD

    Science.gov (United States)

    Bruce, E. A.

    1980-01-01

    The software developed by the IPAD project, a new and very powerful tool for the implementation of integrated Computer Aided Design (CAD) systems in the aerospace engineering community, is discussed. The IPAD software is a tool and, as such, can be well applied or misapplied in any particular environment. The many benefits of an integrated CAD system are well documented, but there are few such systems in existence, especially in the mechanical engineering disciplines, and therefore little available experience to guide the implementor.

  4. Structure and Electronic Properties of Cerium Orthophosphate: Theory and Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Adelstein, Nicole; Mun, B. Simon; Ray, Hannah; Ross Jr, Phillip; Neaton, Jeffrey; De Jonghe, Lutgard

    2010-07-27

    Structural and electronic properties of cerium orthophosphate (CePO{sub 4}) are calculated using density functional theory (DFT) with the local spin-density approximation (LSDA+U), with and without gradient corrections (GGA-(PBE)+U), and compared to X-ray diffraction and photoemission spectroscopy measurements. The density of states is found to change significantly as the Hubbard parameter U, which is applied to the Ce 4f states, is varied from 0 to 5 eV. The calculated structural properties are in good agreement with experiment and do not change significantly with U. Choosing U = 3 eV for LDSA provides the best agreement between the calculated density of states and the experimental photoemission spectra.

  5. Engineering development for a small-scale recirculator experiment

    International Nuclear Information System (INIS)

    Newton, M.A.; Deadrick, F.J.; Hanks, R.L.; Hawkins, S.A.; Holm, K.A.; Kirbie, H.C.; Karpenko, V.P.; Nattrass, L.A.; Longinotti, D.B.

    1995-01-01

    Lawrence Livermore National Laboratory (LLNL) is evaluating the physics and technology of recirculating induction accelerators for heavy-ion inertial-fusion drivers. As part of this evaluation, the authors are building a small-scale recirculator to demonstrate the concept and to use as a test bed for the development of recirculator technologies. System designs have been completed and components are presently being designed and developed for the small-scale recirculator. This paper discusses results of the design and development activities that are presently being conducted to implement the small-scale recirculator experiments. An, overview of the system design is presented along with a discussion of the implications of this design on the mechanical and electrical hardware. The paper focuses primarily on discussions of the development and design of the half-lattice period hardware and the advanced solid-state modulator

  6. Θ13 Neutrino Experiment at the Diablo Canyon Power Plant. LBNL Engineering Summary Report

    International Nuclear Information System (INIS)

    Oshatz, Daryl

    2004-01-01

    This summary document describes the results of conceptual design and cost estimates performed by LBNL Engineering staff between October 10, 2003 and March 12, 2004 for the proposed θ 13 neutrino experiment at the Diablo Canyon Power Plant (DCPP). This document focuses on the detector room design concept and mechanical engineering issues associated with the neutrino detector structures. Every effort has been made not to duplicate information contained in the last LBNL Engineering Summary Report dated October 10, 2003. Only new or updated information is included in this document

  7. Experience with a top-down versus bottom-up nuclear engineering educational paradigm

    International Nuclear Information System (INIS)

    Harms, A.A.

    1991-01-01

    Nuclear engineering courses are generally taught from a top-down pedagogical perspective; i.e., one begins with a body of knowledge drawn from advanced nuclear science, engineering, and experience and from this distills a selected part to match the intellectual capacity of the class. This pedagogical approach has evidently been most effect at the graduate level of instruction as evidenced by the ready entry of masters and doctoral students into the professions. A schematic depiction of this approach is suggested and is extended to the undergraduate level of nuclear engineering education

  8. Accreditation of Spanish engineering programs, first experiences. The case of the Terrassa School of Engineering

    Directory of Open Access Journals (Sweden)

    Mª Dolores Álvarez

    2016-03-01

    Full Text Available The implementation of the European Space for Higher Education has entailed new requirements for Spanish Higher Education Programs. Regulations (RD 1393, 2007 stablish that university programs, in order to have official validity, must be submitted to an external evaluation process before their official implementation, denominated Validation, and to an ex-post process or Accreditation. Terrassa School of Engineering (EET was one of the first schools in Spain to adapt to the European Space for Higher Education, in the academic period 2009-10 and then, one of the first university institutions submitted to an accreditation process. In this communication, the important role of the Internal Quality Assurance System in the assessment of the school’s programs is exposed as well as the approach followed in the key steps of the process: Accreditation

  9. Optimizing DMPK Properties: Experiences from a Big Pharma DMPK Department.

    Science.gov (United States)

    Sohlenius-Sternbeck, Anna-Karin; Janson, Juliette; Bylund, Johan; Baranczewski, Pawel; Breitholtz-Emanuelsson, Anna; Hu, Yin; Tsoi, Carrie; Lindgren, Anders; Gissberg, Olle; Bueters, Tjerk; Briem, Sveinn; Juric, Sanja; Johansson, Jenny; Bergh, Margareta; Hoogstraate, Janet

    2016-01-01

    The disposition of a drug is dependent on interactions between the body and the drug, its molecular properties and the physical and biological barriers presented in the body. In order for a drug to have a desired pharmacological effect it has to have the right properties to be able to reach the target site in sufficient concentration. This review details how drug metabolism and pharmacokinetics (DMPK) and physicochemical deliveries played an important role in data interpretation and compound optimization at AstraZeneca R&D in Södertälje, Sweden. A selection of assays central in the evaluation of the DMPK properties of new chemical entities is presented, with guidance and consideration on assay outcome interpretation. Early in projects, solubility, LogD, permeability and metabolic stability were measured to support effective optimization of DMPK properties. Changes made to facilitate high throughput, efficient bioanalysis and the handling of large amounts of samples are described. Already early in drug discovery, we used an integrated approach for the prediction of the fate of drugs in human (early dose to man) based on data obtained from in vitro experiments. The early dose to man was refined with project progression, which triggered more intricate assays and experiments. At later stages, preclinical in vivo pharmacokinetic (PK) data was integrated with pharmacodynamics (PD) to allow predictions of required dose, dose intervals and exposure profile to achieve the desired effect in man. A well-defined work flow of DMPK activities from early lead identification up to the selection of a candidate drug was developed. This resulted in a cost effective and efficient optimization of chemical series, and facilitated informed decision making throughout project progress.

  10. Engineering Properties of Treated Natural Hemp Fiber-Reinforced Concrete

    Directory of Open Access Journals (Sweden)

    Xiangming Zhou

    2017-06-01

    Full Text Available In recent years, the construction industry has seen a significant rise in the use of natural fibers, for producing building materials. Research has shown that treated hemp fiber-reinforced concrete (THFRC can provide a low-cost building material for residential and low-rise buildings, while achieving sustainable construction and meeting future environmental targets. This study involved enhancing the mechanical properties of hemp fiber-reinforced concrete through the Ca(OH2 solution pretreatment of fibers. Both untreated (UHFRC and treated (THFRC hemp fiber-reinforced concrete were tested containing 15-mm length fiber, at a volume fraction of 1%. From the mechanical strength tests, it was observed that the 28-day tensile and compressive strength of THFRC was 16.9 and 10% higher, respectively, than UHFRC. Based on the critical stress intensity factor (KICs and critical strain energy release rate (GICs, the fracture toughness of THFRC at 28 days was also found to be 7–13% higher than UHFRC. Additionally, based on the determined brittleness number (Q and modulus of elasticity, the THFRC was found to be 11% less brittle and 10.8% more ductile. Furthermore, qualitative analysis supported many of the mechanical strength findings through favorable surface roughness observed on treated fibers and resistance to fiber pull-out.

  11. Sensitivities to neutrino electromagnetic properties at the TEXONO experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kosmas, T.S., E-mail: hkosmas@uoi.gr [Division of Theoretical Physics, University of Ioannina, GR 45110 Ioannina (Greece); Miranda, O.G., E-mail: omr@fis.cinvestav.mx [Departamento de Física, Centro de Investigación y de Estudios Avanzados del IPN, Apdo. Postal 14-740 07000 Mexico, DF (Mexico); Papoulias, D.K., E-mail: dimpap@cc.uoi.gr [Division of Theoretical Physics, University of Ioannina, GR 45110 Ioannina (Greece); AHEP Group, Instituto de Física Corpuscular – C.S.I.C./Universitat de València, Edificio de Institutos de Paterna, C/Catedratico José Beltrán, 2 E-46980 Paterna (València) (Spain); Tórtola, M., E-mail: mariam@ific.uv.es [AHEP Group, Instituto de Física Corpuscular – C.S.I.C./Universitat de València, Edificio de Institutos de Paterna, C/Catedratico José Beltrán, 2 E-46980 Paterna (València) (Spain); Valle, J.W.F. [AHEP Group, Instituto de Física Corpuscular – C.S.I.C./Universitat de València, Edificio de Institutos de Paterna, C/Catedratico José Beltrán, 2 E-46980 Paterna (València) (Spain)

    2015-11-12

    The possibility of measuring neutral-current coherent elastic neutrino–nucleus scattering (CENNS) at the TEXONO experiment has opened high expectations towards probing exotic neutrino properties. Focusing on low threshold Germanium-based targets with kg-scale mass, we find a remarkable efficiency not only for detecting CENNS events due to the weak interaction, but also for probing novel electromagnetic neutrino interactions. Specifically, we demonstrate that such experiments are complementary in performing precision Standard Model tests as well as in shedding light on sub-leading effects due to neutrino magnetic moment and neutrino charge radius. This work employs realistic nuclear structure calculations based on the quasi-particle random phase approximation (QRPA) and takes into consideration the crucial quenching effect corrections. Such a treatment, in conjunction with a simple statistical analysis, shows that the attainable sensitivities are improved by one order of magnitude as compared to previous studies.

  12. GeneRank: Using search engine technology for the analysis of microarray experiments

    Directory of Open Access Journals (Sweden)

    Breitling Rainer

    2005-09-01

    Full Text Available Abstract Background Interpretation of simple microarray experiments is usually based on the fold-change of gene expression between a reference and a "treated" sample where the treatment can be of many types from drug exposure to genetic variation. Interpretation of the results usually combines lists of differentially expressed genes with previous knowledge about their biological function. Here we evaluate a method – based on the PageRank algorithm employed by the popular search engine Google – that tries to automate some of this procedure to generate prioritized gene lists by exploiting biological background information. Results GeneRank is an intuitive modification of PageRank that maintains many of its mathematical properties. It combines gene expression information with a network structure derived from gene annotations (gene ontologies or expression profile correlations. Using both simulated and real data we find that the algorithm offers an improved ranking of genes compared to pure expression change rankings. Conclusion Our modification of the PageRank algorithm provides an alternative method of evaluating microarray experimental results which combines prior knowledge about the underlying network. GeneRank offers an improvement compared to assessing the importance of a gene based on its experimentally observed fold-change alone and may be used as a basis for further analytical developments.

  13. GeneRank: using search engine technology for the analysis of microarray experiments.

    Science.gov (United States)

    Morrison, Julie L; Breitling, Rainer; Higham, Desmond J; Gilbert, David R

    2005-09-21

    Interpretation of simple microarray experiments is usually based on the fold-change of gene expression between a reference and a "treated" sample where the treatment can be of many types from drug exposure to genetic variation. Interpretation of the results usually combines lists of differentially expressed genes with previous knowledge about their biological function. Here we evaluate a method--based on the PageRank algorithm employed by the popular search engine Google--that tries to automate some of this procedure to generate prioritized gene lists by exploiting biological background information. GeneRank is an intuitive modification of PageRank that maintains many of its mathematical properties. It combines gene expression information with a network structure derived from gene annotations (gene ontologies) or expression profile correlations. Using both simulated and real data we find that the algorithm offers an improved ranking of genes compared to pure expression change rankings. Our modification of the PageRank algorithm provides an alternative method of evaluating microarray experimental results which combines prior knowledge about the underlying network. GeneRank offers an improvement compared to assessing the importance of a gene based on its experimentally observed fold-change alone and may be used as a basis for further analytical developments.

  14. Methods for assessing basic particle properties and cytotoxicity of engineered nanoparticles

    NARCIS (Netherlands)

    Kalantzi, O.I.; Biskos, G.

    2014-01-01

    The increasing penetration of materials and products containing engineered nanoparticles (ENPs) to the market is posing many concerns regarding their environmental impacts. To assess these impacts, there is an urgent need of techniques for determining the health-related properties of ENPs and

  15. Role of the Property Engineering in the units' construction of the Cernavoda nuclear power plant

    International Nuclear Information System (INIS)

    Esteban-Zazo Gomez, J. A.; Varas Suarez, M. I.; Dehalu, J. M.; Giura, A.

    2010-01-01

    The engineering of the property acts as owner's representative to ensure that the technical execution of the work is done according to the specifications. Normally, his paper complements the role of project management often tends to be more focused on the monitoring and supervision of commercial and financial aspects of it.

  16. The Structure of Design Theories, and an Analysis of their Use in Software Engineering Experiments

    NARCIS (Netherlands)

    Wieringa, Roelf J.; Daneva, Maia; Condori-Fernandez, Nelly

    In this paper we analyse possible reasons for the relatively low use of theories in software engineering (SE) papers found by Hannay et al.~cite{Hannay07}. We provide an initial explanation in terms of properties of theories, test this by analyzing 32 of the 40 theories reviewed by Hannay et al.,

  17. A Low Cost Implementation of an Existing Hands-on Laboratory Experiment in Electronic Engineering

    Directory of Open Access Journals (Sweden)

    Clement Onime

    2014-10-01

    Full Text Available In engineering the pedagogical content of most formative programmes includes a significant amount of practical laboratory hands-on activity designed to deliver knowledge acquisition from actual experience alongside traditional face-to-face classroom based lectures and tutorials; this hands-on aspect is not always adequately addressed by current e-learning platforms. An innovative approach to e-learning in engineering, named computer aided engineering education (CAEE is about the use of computer aids for the enhanced, interactive delivery of educational materials in different fields of engineering through two separate but related components; one for classroom and another for practical hands-on laboratory work. The component for hands-on laboratory practical work focuses on the use of mixed reality (video-based augmented reality tools on mobile devices/platforms. This paper presents the computer aided engineering education (CAEE implementation of a laboratory experiment in micro-electronics that highlights some features such as the ability to closely implement an existing laboratory based hands-on experiment with lower associated costs and the ability to conduct the experiment off-line while maintaining existing pedagogical contents and standards.

  18. Improving magnetic properties of MgB{sub 2} bulk superconductors by synthetic engine oil treatment

    Energy Technology Data Exchange (ETDEWEB)

    Taylan Koparan, E., E-mail: etaylan20@gmail.com [Department of Science Education, Eregli Faculty of Education, Bulent Ecevit University, TR-67300, Zonguldak (Turkey); Savaskan, B. [Energy Systems Engineering, Faculty of Technology, Karadeniz Technical University, 61830, Of, Trabzon (Turkey); Yanmaz, E. [Department of Mechatronics, Faculty of Engineering and Architecture, İstanbul Gelişim University, İstanbul (Turkey)

    2016-08-15

    Highlights: • The effects of synthetic engine oil treatment on magnetic properties of bulk MgB{sub 2} superconductors has been first time investigated and reported. • Synthetic engine oil used as a product which is cheap and a rich carbon source obviously has improved the superconducting magnetic properties of MgB{sub 2}. • The critical current density of all of MgB{sub 2} samples immersed at different standby time in engine oil in whole field range has been better than that of the pure MgB{sub 2} sample. • The MgB{sub 2} sample immersed at 300 min standby time in synthetic engine oil has the best performance compared to other samples. - Abstract: The present study focuses on the effects of standby time of the MgB{sub 2} samples immersed in synthetic engine oil on the critical current density ( J{sub c}(H)), magnetic field dependence of the pinning force density f{sub p}(b) and T{sub c} performances of MgB{sub 2} bulk superconductors. Synthetic engine oil was used as a product which is cheap and a rich carbon source. Manufactured MgB{sub 2} pellet samples were immersed at different standby time of 30 min, 120 min, 300 min and 1440 min in synthetic engine oil after the first heating process. Finally, MgB{sub 2} samples immersed in synthetic engine oil were sintered at 1000 °C and kept for 15 min in Ar atmosphere. The critical current density of all of MgB{sub 2} samples immersed at different standby time in engine oil in whole field range was better than that of the pure MgB{sub 2} sample because of the number of the pinning centers. The MgB{sub 2} sample immersed at 300 min standby time in synthetic engine oil has the best performance compared to other samples. The J{sub c} value for the pure sample is 2.0 × 10{sup 3} A/cm{sup 2}, whereas for the MgB{sub 2} sample immersed at 300 min standby time in engine oil the J{sub c} is enhanced to 4.8 × 10{sup 3} A/cm{sup 2} at 5 K and 3 T. The superconducting transition temperature (T{sub c}) did not change

  19. Improving magnetic properties of MgB_2 bulk superconductors by synthetic engine oil treatment

    International Nuclear Information System (INIS)

    Taylan Koparan, E.; Savaskan, B.; Yanmaz, E.

    2016-01-01

    Highlights: • The effects of synthetic engine oil treatment on magnetic properties of bulk MgB_2 superconductors has been first time investigated and reported. • Synthetic engine oil used as a product which is cheap and a rich carbon source obviously has improved the superconducting magnetic properties of MgB_2. • The critical current density of all of MgB_2 samples immersed at different standby time in engine oil in whole field range has been better than that of the pure MgB_2 sample. • The MgB_2 sample immersed at 300 min standby time in synthetic engine oil has the best performance compared to other samples. - Abstract: The present study focuses on the effects of standby time of the MgB_2 samples immersed in synthetic engine oil on the critical current density ( J_c(H)), magnetic field dependence of the pinning force density f_p(b) and T_c performances of MgB_2 bulk superconductors. Synthetic engine oil was used as a product which is cheap and a rich carbon source. Manufactured MgB_2 pellet samples were immersed at different standby time of 30 min, 120 min, 300 min and 1440 min in synthetic engine oil after the first heating process. Finally, MgB_2 samples immersed in synthetic engine oil were sintered at 1000 °C and kept for 15 min in Ar atmosphere. The critical current density of all of MgB_2 samples immersed at different standby time in engine oil in whole field range was better than that of the pure MgB_2 sample because of the number of the pinning centers. The MgB_2 sample immersed at 300 min standby time in synthetic engine oil has the best performance compared to other samples. The J_c value for the pure sample is 2.0 × 10"3 A/cm"2, whereas for the MgB_2 sample immersed at 300 min standby time in engine oil the J_c is enhanced to 4.8 × 10"3 A/cm"2 at 5 K and 3 T. The superconducting transition temperature (T_c) did not change with the increasing standby time of the samples in synthetic engine oil at all. The best diamagnetic property was

  20. Science Data Report for the Optical Properties Monitor (OPM) Experiment

    Science.gov (United States)

    Wilkes, D. R.; Zwiener, J. M.; Carruth, Ralph (Technical Monitor)

    2001-01-01

    This science data report describes the Optical Properties Monitor (OPM) experiment and the data gathered during its 9-mo exposure on the Mir space station. Three independent optical instruments made up OPM: an integrating sphere spectral reflectometer, vacuum ultraviolet spectrometer, and a total integrated scatter instrument. Selected materials were exposed to the low-Earth orbit, and their performance monitored in situ by the OPM instruments. Coinvestigators from four NASA Centers, five International Space Station contractors, one university, two Department of Defense organizations, and the Russian space company, Energia, contributed samples to this experiment. These materials included a number of thermal control coatings, optical materials, polymeric films, nanocomposites, and other state-of-the-art materials. Degradation of some materials, including aluminum conversion coatings and Beta cloth, was greater than expected. The OPM experiment was launched aboard the Space Shuttle on mission STS-81 in January 1997 and transferred to the Mir space station. An extravehicular activity (EVA) was performed in April 1997 to attach the OPM experiment to the outside of the Mir/Shuttle Docking Module for space environment exposure. OPM was retrieved during an EVA in January 1998 and was returned to Earth on board the Space Shuttle on mission STS-89.

  1. Engineered Surface Properties of Porous Tungsten from Cryogenic Machining

    Science.gov (United States)

    Schoop, Julius Malte

    Porous tungsten is used to manufacture dispenser cathodes due to it refractory properties. Surface porosity is critical to functional performance of dispenser cathodes because it allows for an impregnated ceramic compound to migrate to the emitting surface, lowering its work function. Likewise, surface roughness is important because it is necessary to ensure uniform wetting of the molten impregnate during high temperature service. Current industry practice to achieve surface roughness and surface porosity requirements involves the use of a plastic infiltrant during machining. After machining, the infiltrant is baked and the cathode pellet is impregnated. In this context, cryogenic machining is investigated as a substitutionary process for the current plastic infiltration process. Along with significant reductions in cycle time and resource use, surface quality of cryogenically machined un-infiltrated (as-sintered) porous tungsten has been shown to significantly outperform dry machining. The present study is focused on examining the relationship between machining parameters and cooling condition on the as-machined surface integrity of porous tungsten. The effects of cryogenic pre-cooling, rake angle, cutting speed, depth of cut and feed are all taken into consideration with respect to machining-induced surface morphology. Cermet and Polycrystalline diamond (PCD) cutting tools are used to develop high performance cryogenic machining of porous tungsten. Dry and pre-heated machining were investigated as a means to allow for ductile mode machining, yet severe tool-wear and undesirable smearing limited the feasibility of these approaches. By using modified PCD cutting tools, high speed machining of porous tungsten at cutting speeds up to 400 m/min is achieved for the first time. Beyond a critical speed, brittle fracture and built-up edge are eliminated as the result of a brittle to ductile transition. A model of critical chip thickness ( hc ) effects based on cutting

  2. Dielectric Property Enhancement in Polymer Composites with Engineered Interfaces

    Science.gov (United States)

    Krentz, Timothy Michael

    This thesis reports studies into the dielectric behavior of polymer composites filled with silica nanoparticles. The permittivity and dielectric breakdown strength (DBS) of these materials are critical to their performance in insulating applications such as high voltage power transmission. Until now, the mechanisms which lead to improvements in DBS in these systems have been poorly understood, in part because the effects of dispersion of the filler and the filler's surface electronic characteristics have been confused. The new surface modifications created in this thesis permit these two parameters to be addressed independently, leading to the hypothesis that nanocomposite dielectric materials exhibit DBS enhancement when electron avalanches are prevented from proceeding to reach a critical size capable of causing failure. The same control of dispersion and surface properties also lead to changes in the permittivity of the composite based upon the polarizability and trapping behavior of the filler. In this work, the dispersion and surface states of silica nanoparticles were independently controlled with two separate populations of surface molecules. Two matrix materials were studied, and in each system, a different, matrix-compatible long chain polymer is required to control dispersion. Conversely, a second population of short molecules is shown to be capable of creating electronic traps associated with the silica nanoparticle surface which lead to DBS enhancements largely independent of the matrix, indicating that the same failure mechanism is operating in both epoxy and polypropylene. Progressive variation in dispersion quality is attained with this surface modification scheme. This creates progressively smaller volumes of matrix polymer unaffected by the filler. This work shows that when these volumes approach and become smaller than the same scale as predicted for electron avalanches, the greatest changes in DBS are seen. Likewise, the plateau behavior of this

  3. Female peer mentors early in college increase women���s positive academic experiences and retention in engineering

    OpenAIRE

    Dennehy, Tara C.; Dasgupta, Nilanjana

    2017-01-01

    The scarcity of women in the American science and engineering workforce is a well-recognized problem. However, field-tested interventions outside artificial laboratory settings are few. We provide evidence from a multiyear field experiment demonstrating that women in engineering who were assigned a female (but not male) peer mentor experienced more belonging, motivation, and confidence in engineering, better retention in engineering majors, and greater engineering career aspirations. Female m...

  4. Effect of soot on oil properties and wear of engine components

    International Nuclear Information System (INIS)

    Green, D A; Lewis, R

    2007-01-01

    The objective of the work outlined in this paper was to increase the understanding of the wear mechanisms that occur within a soot contaminated contact zone, to help in future development of a predictive wear model to assist in the automotive engine valve train design process. The paper builds on previous work by the author, through testing of different lubricants and increased levels of soot contamination. Wear testing has been carried out using specimens operating under realistic engine conditions, using a reciprocating test-rig specifically designed for this application, where a steel disc is held in a heated bath of oil and a steel ball is attached to a reciprocating arm (replicating a sliding elephant's foot valve train contact). Detailed analysis of the test specimens has been performed using scanning electron microscopy to identify wear features relating to the proposed wear mechanisms. Analysis of worn engine components from durability engine tests has also been carried out for a comparison between specimen tests and engine testing. To assist the understanding of the wear test results obtained, the physical properties of contaminated lubricants were investigated, through viscosity, traction and friction measurements. The results have revealed how varying lubrication conditions change the wear rate of engine components and determine the wear mechanism that dominates in specific situations. Testing has also shown the positive effects of advanced engine lubricants to reduce the amount of wear produced with soot present

  5. Determining the optimum conditions for modified diesel fuel combustion considering its emission, properties and engine performance

    International Nuclear Information System (INIS)

    Fayyazbakhsh, Ahmad; Pirouzfar, Vahid

    2016-01-01

    Highlights: • Gas emissions, fuel properties and performance engine modeling. • Optimization of new modified fuel prepared from n-Butanol and Nano particles. • Model accuracy analysis. - Abstract: This essay scrutinizes an experimental study conducted to appraise the influence of using n-Butanol with diesel fuel in 5% and 10% (volume) n-Butanol, 1% nitro methane (NM), injection timing and two Nano-particles (alumina and a type of silica powder) on the engine performance (brake specific fuel consumption and engine power), fuel properties (Cetane number and flash point) and exhaust emissions (soot, NO_x and CO) of an engine with 4-cylinder (with a system of common rail fuel injection), intercooling, cooled exhaust gas recirculation (EGR), and turbocharged. The tests are conducted by varying the engine load (25 and 75 nm) and changing engine speed (1500 and 2200 rpm). Normal Butanol presents better brake specific fuel consumption (BSFC) but this blend doesn’t reflect better engine power. All the percentages of n-Butanol in the fuel make Cetane number decrease but adding 1% of nitro methane makes Cetane number increase. For all the n-Butanol, the percentage flash makes the fuel decrease in comparison to pure diesel fuel. The current experimental study demonstrates that adding the n-Butanol and nitro methane to diesel fuel direct into diminishing soot emission. In contrast, this blend raises NO_x and CO emissions. Furthermore, this research indicates that the increase of engine speed dwindle air pollutants and enhances BSFC. It also remarks that power gets increased at low engine speed. However, power gets reducedat high speed. This article represents that the increasing of engine load leads to increasing all of air pollutant, increasing of power and decreasing of brake specific fuel consumption. Both the Cetane number and flash point are independent from engine speed and engine load. The present paper shows that the effect of silica with high percentage of n

  6. Ethics and engineering courses at Delft University of Technology: contents, educational setup and experiences.

    Science.gov (United States)

    van de Poel, I R; Zandvoort, H; Brumsen, M

    2001-04-01

    This article reports on the development and teaching of compulsory courses on ethics and engineering at Delft University of Technology (DUT). Attention is paid to the teaching goals, the educational setup and methods, the contents of the courses, involvement of staff from engineering schools, experiences to date, and challenges for the future. The choices made with respect to the development and teaching of the courses are placed within the European and Dutch context and are compared and contrasted with the American situation and experiences.

  7. Effect of Coating Palm Oil Clinker Aggregate on the Engineering Properties of Normal Grade Concrete

    Directory of Open Access Journals (Sweden)

    Fuad Abutaha

    2017-10-01

    Full Text Available Palm oil clinker (POC is a waste material generated in large quantities from the palm oil industry. POC, when crushed, possesses the potential to serve as an aggregate for concrete production. Experimental investigation on the engineering properties of concrete incorporating POC as aggregate and filler material was carried out in this study. POC was partially and fully used to replace natural coarse aggregate. The volumetric replacements used were 0%, 20%, 40%, 60%, 80%, and 100%. POC, being highly porous, negatively affected the fresh and hardened concrete properties. Therefore, the particle-packing (PP method was adopted to measure the surface and inner voids of POC coarse aggregate in the mixtures at different substitution levels. In order to enhance the engineering properties of the POC concrete, palm oil clinker powder (POCP was used as a filler material to fill up and coat the surface voids of POC coarse, while the rest of the mix constituents were left as the same. Fresh and hardened properties of the POC concrete with and without coating were determined, and the results were compared with the control concrete. The results revealed that coating the surface voids of POC coarse with POCP significantly improved the engineering properties as well as the durability performance of the POC concrete. Furthermore, using POC as an aggregate and filler material may reduce the continuous exploitation of aggregates from primary sources. Also, this approach offers an environmental friendly solution to the ongoing waste problems associated with palm oil waste material.

  8. Nonmetallic engineered barriers, their properties and role in a geologic repository for high level radioactive waste

    International Nuclear Information System (INIS)

    Lisy, F.

    1994-01-01

    The efficiency of engineered barrier systems depends to a great extent on the properties of the materials used. Backfill and sealing materials must fulfill certain requirements and criteria. They must feature low hydraulic conductivity, high retardation capacity, extremely good sorption properties for a wide range of radionuclides potentially leachable from the deposited waste, low permeability, good compatibility with engineered and natural barriers, good workability, and availability in the necessary quantity and at a reasonable price. Some basic properties are presented of materials which fulfill, to a considerable degree, these requirements and which are thus suggested as suitable backfills, sealings of buffers, namely clay- and cement-based materials (concretes, mortars, etc.). A brief information is also given on some other materials like bitumen, asphalt, etc. (Z.S.) 4 refs

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

    Science.gov (United States)

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

    2014-07-01

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

  10. Challenges in Obtaining Property Access: The FUSRAP Maywood Site Experience - 13433

    Energy Technology Data Exchange (ETDEWEB)

    Kollar, William [Shaw Environmental, Inc., 100 West Hunter Avenue, Maywood, NJ 07607 (United States)

    2013-07-01

    The Formerly Utilized Sites Remedial Action Program (FUSRAP) is the US government program started in 1974 to identify, investigate and clean up or control sites that became contaminated as a result of the nation's early atomic programs. Many of these sites are not owned by the federal government and therefore require owner permission to enter. The experience in pursuing such access at the FUSRAP Maywood Superfund Site (the Maywood Site or the Site) in Bergen County, New Jersey, is extensive. Since the US Army Corps of Engineers (the Corps) assumed responsibility for the Maywood Site from the US Department of Energy in 1997, at least 186 separate property access agreements (known in FUSRAP as a Real Estate Right-of- Entry or ROE) have been executed between the Corps and approximately 55 different land owners and tenant occupants at the Maywood Site (agreement renewals with the same owners over time account for the difference). Maywood's experience during the Corps' tenure, reflected here in three case studies of representative property access efforts, offers some lessons and best practices that may apply to other remedial programs. While the Site Community Relations Manager (the author of this paper) managed the property access task, multi-disciplinary support from across the project was also critical to success in this endeavor. (authors)

  11. Challenges in Obtaining Property Access: The FUSRAP Maywood Site Experience - 13433

    International Nuclear Information System (INIS)

    Kollar, William

    2013-01-01

    The Formerly Utilized Sites Remedial Action Program (FUSRAP) is the US government program started in 1974 to identify, investigate and clean up or control sites that became contaminated as a result of the nation's early atomic programs. Many of these sites are not owned by the federal government and therefore require owner permission to enter. The experience in pursuing such access at the FUSRAP Maywood Superfund Site (the Maywood Site or the Site) in Bergen County, New Jersey, is extensive. Since the US Army Corps of Engineers (the Corps) assumed responsibility for the Maywood Site from the US Department of Energy in 1997, at least 186 separate property access agreements (known in FUSRAP as a Real Estate Right-of- Entry or ROE) have been executed between the Corps and approximately 55 different land owners and tenant occupants at the Maywood Site (agreement renewals with the same owners over time account for the difference). Maywood's experience during the Corps' tenure, reflected here in three case studies of representative property access efforts, offers some lessons and best practices that may apply to other remedial programs. While the Site Community Relations Manager (the author of this paper) managed the property access task, multi-disciplinary support from across the project was also critical to success in this endeavor. (authors)

  12. The impact of program experiences on the retention of women engineering students in Mexico

    Science.gov (United States)

    Villa, Maria Del Carmen Garcia

    This qualitative study sought to describe and understand the experiences of female students attending engineering colleges in Mexico and the sources of support and strategies that helped them persist in their programs. The participants were 20 women engineering students enrolled in at least their third year in selected colleges of engineering in Mexico, in both public and private universities, and pursuing a variety of engineering majors. Findings focus on the experiences of female students that helped them stay in their programs. Participants described their experiences in college as very challenging and perceived the environment as hostile and uncertain. In addition, patriarchal Mexican cultural values and stereotypes were identified by students as influencing and helping shape the engineering environment. However, in this context, participants were able to find sources of support and use strategies that helped them remain in their majors, such as a strong desire to succeed, a perceived academic self-ability; and support from their families, peers, institutions, and---most importantly---their professors. Furthermore, the fact that participants were able to persist in their programs gave them a sense of pride and satisfaction that was shared by their families, peers, and faculty. In addition, participants experienced contradictory forces and were constantly negotiating between rejecting traditional gender norms and upholding the norms that are so deeply engrained in Mexican society. Finally, as the students advanced in their programs and became "accepted to the club," they tended to reproduce the male-dominated value system present in engineering colleges accepting their professors' expectations of being "top students," accepting the elitist culture of engineering superiority, and embracing the protection given by their male peers. Retention of Mexican female engineering students is important for all engineering colleges, but cultural factors must be taken into

  13. National Educators' Workshop: Update 2002 - Standard Experiments in Engineering, Materials Science, and Technology

    Science.gov (United States)

    Prior, Edwin J. (Compiler); Jacobs, James A. (Compiler); Chung, W. Richard (Compiler)

    2003-01-01

    This document contains a collection of experiments presented and demonstrated at the National Educators' Workshop: Update 2002 held in San Jose, California, October 13-16,2002. This publication provides experiments and demonstrations that can serve as a valuable guide to faculty who are interested in useful activities for their students. The material was the result of years of research aimed at better methods of teaching technical subjects. The experiments developed by faculty, scientists, and engineers throughout the United States and abroad add to the collection from past workshops. They include a blend of experiments on new materials and traditional materials.

  14. A summary of computational experience at GE Aircraft Engines for complex turbulent flows in gas turbines

    Science.gov (United States)

    Zerkle, Ronald D.; Prakash, Chander

    1995-01-01

    This viewgraph presentation summarizes some CFD experience at GE Aircraft Engines for flows in the primary gaspath of a gas turbine engine and in turbine blade cooling passages. It is concluded that application of the standard k-epsilon turbulence model with wall functions is not adequate for accurate CFD simulation of aerodynamic performance and heat transfer in the primary gas path of a gas turbine engine. New models are required in the near-wall region which include more physics than wall functions. The two-layer modeling approach appears attractive because of its computational complexity. In addition, improved CFD simulation of film cooling and turbine blade internal cooling passages will require anisotropic turbulence models. New turbulence models must be practical in order to have a significant impact on the engine design process. A coordinated turbulence modeling effort between NASA centers would be beneficial to the gas turbine industry.

  15. Gelatin Scaffolds with Controlled Pore Structure and Mechanical Property for Cartilage Tissue Engineering.

    Science.gov (United States)

    Chen, Shangwu; Zhang, Qin; Nakamoto, Tomoko; Kawazoe, Naoki; Chen, Guoping

    2016-03-01

    Engineering of cartilage tissue in vitro using porous scaffolds and chondrocytes provides a promising approach for cartilage repair. However, nonuniform cell distribution and heterogeneous tissue formation together with weak mechanical property of in vitro engineered cartilage limit their clinical application. In this study, gelatin porous scaffolds with homogeneous and open pores were prepared using ice particulates and freeze-drying. The scaffolds were used to culture bovine articular chondrocytes to engineer cartilage tissue in vitro. The pore structure and mechanical property of gelatin scaffolds could be well controlled by using different ratios of ice particulates to gelatin solution and different concentrations of gelatin. Gelatin scaffolds prepared from ≥70% ice particulates enabled homogeneous seeding of bovine articular chondrocytes throughout the scaffolds and formation of homogeneous cartilage extracellular matrix. While soft scaffolds underwent cellular contraction, stiff scaffolds resisted cellular contraction and had significantly higher cell proliferation and synthesis of sulfated glycosaminoglycan. Compared with the gelatin scaffolds prepared without ice particulates, the gelatin scaffolds prepared with ice particulates facilitated formation of homogeneous cartilage tissue with significantly higher compressive modulus. The gelatin scaffolds with highly open pore structure and good mechanical property can be used to improve in vitro tissue-engineered cartilage.

  16. Optimal Design of Experiments for Parametric Identification of Civil Engineering Structures

    OpenAIRE

    Kirkegaard, Poul Henning

    1991-01-01

    Optimal Systems of experiments for parametric identification of civil engineering structures is investigated. Design of experiments for parametric identification of dynamic systems is usually done by minimizing a scalar measure, e.g the determinant, the trace ect., of an estimated parameter covariance matrix, based on prior knowledge. The experimental conditions available for adjustment, considering in this thesis, are input signal, sampling rate, the location of sensors and number of sensors.

  17. Recent chemical engineering requirements as the result of TMI on-site experience

    International Nuclear Information System (INIS)

    Brooksbank, R.E. Sr.

    1980-01-01

    From the experiences gained from the on-site experience at TMI, it is apparent that the role of chemical engineers should increase in order for the nuclear option to proceed in a safe and efficient fashion. It is also obvious that as the results of the reports investigating the causes and effects of the accident come to light and attempts to backfit system designs to prevent a recurrence are studied, more technical demands will be placed on the profession

  18. EXPERIENCES INITIATING SOFTWARE PRODUCT LINE ENGINEERING IN SMALL TEAMS WITH PULSE

    DEFF Research Database (Denmark)

    Mærsk-Møller, Hans Martin; Jørgensen, Bo Nørregaard

    2010-01-01

    Small teams of software engineers are represented both in small companies and semi-independent fractions in medium and large companies. Even though some results and experience papers have been published in the context of Small- and Medium-Sized Enterprises (SMEs), there is a lack of experience pa...... an existing methodology, PuLSETM, drew advantages of NetBeans Rich Client Platform, and based the product line on the existing application....

  19. Parts, materials, and processes experience summary, volume 2. [design, engineering, and quality control

    Science.gov (United States)

    1973-01-01

    This summary provides the general engineering community with the accumulated experience from ALERT reports issued by NASA and the Government-Industry. Data Exchange Program, and related experience gained by Government and industry. It provides expanded information on selected topics by relating the problem area (failure) to the cause, the investigation and findings, the suggestions for avoidance (inspections, screening tests, proper part applications, requirements for manufacturer's plant facilities, etc.), and failure analysis procedures. Diodes, integrated circuits, and transistors are covered in this volume.

  20. Applying Peer Reviews in Software Engineering Education: An Experiment and Lessons Learned

    Science.gov (United States)

    Garousi, V.

    2010-01-01

    Based on the demonstrated value of peer reviews in the engineering industry, numerous industry experts have listed it at the top of the list of desirable development practices. Experience has shown that problems (defects) are eliminated earlier if a development process incorporates peer reviews and that these reviews are as effective as or even…

  1. Peer Mentoring in Engineering: (Un)Shared Experience of Undergraduate Peer Mentors and Mentees

    Science.gov (United States)

    Lim, Jae Hoon; MacLeod, Bailey P.; Tkacik, Peter T.; Dika, Sandra L.

    2017-01-01

    In this qualitative study, we explored the experiences of 26 engineering student mentors and mentees in a peer mentoring program. We found that mentors and mentees exploited the mentoring program's fluid structure and situated social relationships to enact a specific type of academic/professional goal and identity conducive to their entry to one…

  2. Learning to Become Graduate Students: Japanese Women's Experience in the Research Unit in Engineering

    Science.gov (United States)

    Hosaka, Masako

    2010-01-01

    Based on the analysis of 16 interviews with women first-year master's students at two national engineering schools in Japan, this article examines the socialisation role of compulsory undergraduate research experience in Japanese women's decisions to pursue graduate education and choices of the programme. The findings suggest that research…

  3. A Simple Experiment for Teaching Process Intensification by Static Mixing in Chemical Reaction Engineering

    Science.gov (United States)

    Baz-Rodríguez, Sergio; Herrera-Soberanis, Natali; Rodríguez-Novelo, Miguel; Guillén-Francisc, Juana; Rocha-Uribe, José

    2016-01-01

    An experiment for teaching mixing intensification in reaction engineering is described. For this, a simple tubular reactor was constructed; helical static mixer elements were fabricated from stainless steel strips and inserted into the reactor. With and without the internals, the equipment operates as a static mixer reactor or a laminar flow…

  4. The operating experience and incident analysis for High Flux Engineering Test Reactor

    International Nuclear Information System (INIS)

    Zhao Guang

    1999-01-01

    The paper describes the incidents analysis for High Flux Engineering test reactor (HFETR) and introduces operating experience. Some suggestion have been made to reduce the incidents of HFETR. It is necessary to adopt new improvements which enhance the safety and reliability of operation. (author)

  5. Women's Doctoral Student Experiences and Degree Progress in Education versus Engineering

    Science.gov (United States)

    Masterman, Ann Katherine

    2014-01-01

    This study's purpose was to compare the lived experiences of doctoral women studying Education, a prototypically female field, with women studying Engineering, a prototypically male field to illustrate the phenomenon of doctoral degree progress in the two fields. Using critical feminist theory and Valian's (1999) concept of gender schemas, this…

  6. Improving Aerospace Engineering Students' Achievements by an Open Aero Control Experiment Apparatus

    Science.gov (United States)

    Zeng, QingHua; Zhang, WeiHua; Huang, ZheZhi; Dong, RongHua

    2014-01-01

    This paper describes the development of an aero control experiment apparatus (ACEA) for use in aerospace control practical courses. The ACEA incorporates a systematic multihierarchy learning and teaching method, and was designed to improve aerospace engineering students' understanding of unmanned aerial vehicle (UAV) control systems. It offers a…

  7. Campus Climate and the Underrepresented Minority Engineering Student Experience: A Critical Race Study

    Science.gov (United States)

    Mayes, Terrance

    In the current technological era, the number of minorities in science, technology, engineering, and mathematics (STEM) is a crucial factor in predetermining the economic growth of the United States. Since the minority population is growing at much faster rates than the non-minority population, the lack of proportionate production of minority engineers poses a threat to the United States' ability to remain a global competitor in technological innovation. Sixty-three per cent (63%) of undergraduate students who enter engineering majors continue on to graduate in that major. The graduation rate, however, for African-American, Hispanic, and Native-American students in engineering is significantly lower at 39%. As this group represents only a small fraction of the annual student enrollment, engineering programs are graduating these minority groups at rates that are greatly disproportionate to United States demographics. Therefore, researchers are thoroughly investigating certain initiatives that promote academic success among underrepresented minority students in engineering. Colleges and universities have attempted to address the growing achievement gap between underrepresented minority and non-minority engineering students, predominately through various deficit-based interventions, focusing on the student's flaws and problems. As the pipeline for minorities in engineering continues to narrow, it begs the question of whether institutions are focusing on the right solutions to the problem. Critical Race Theory scholars argue that colleges and universities must address institutional climate issues around students, such as racism, microaggressions, and marginalization, before members of oppressed groups can truly succeed. This dissertation explored the unique experiences of underrepresented minority engineering students in a predominately White and Asian campus.

  8. Pulsed power experiments in hydrodynamics and material properties

    CERN Document Server

    Reinovsky, R E

    1999-01-01

    A new application for high performance pulsed power program, the production of high energy density environments in materials for the study of material properties and hydrodynamics in complex geometries, has joined family of radiation source applications in the Stockpile Stewardship. The principle tool for producing high energy density environments is the high precision, magnetically imploded, near-solid density liner. The most attractive pulsed power system for driving such experiments is an ultra-high current, low impedance, microsecond time scale source that is economical both to build and operate. The 25-MJ Atlas capacitor bank system currently under construction at Los Alamos is the first system of its scale specifically designed to drive high precision solid liners. Delivering 30 MA, Atlas will provide liner velocities 12-15 km/sec and kinetic energies of 1-2 MJ /cm with extensive diagnostics and excellent reproducibility. Explosive flux compressor technology provides access to currents exceeding 100 MA ...

  9. Heat experiment design to estimate temperature dependent thermal properties

    International Nuclear Information System (INIS)

    Romanovski, M

    2008-01-01

    Experimental conditions are studied to optimize transient experiments for estimating temperature dependent thermal conductivity and volumetric heat capacity. A mathematical model of a specimen is the one-dimensional heat equation with boundary conditions of the second kind. Thermal properties are assumed to vary nonlinearly with temperature. Experimental conditions refer to the thermal loading scheme, sampling times and sensor location. A numerical model of experimental configurations is studied to elicit the optimal conditions. The numerical solution of the design problem is formulated on a regularization scheme with a stabilizer minimization without a regularization parameter. An explicit design criterion is used to reveal the optimal sensor location, heating duration and flux magnitude. Results obtained indicate that even the strongly nonlinear experimental design problem admits the aggregation of its solution and has a strictly defined optimal measurement scheme. Additional region of temperature measurements with allowable identification error is revealed.

  10. Novel evaporation experiment to determine soil hydraulic properties

    Directory of Open Access Journals (Sweden)

    K. Schneider

    2006-01-01

    Full Text Available A novel experimental approach to determine soil hydraulic material properties for the dry and very dry range is presented. Evaporation from the surface of a soil column is controlled by a constant flux of preconditioned air and the resulting vapour flux is measured by infrared absorption spectroscopy. The data are inverted under the assumptions that (i the simultaneous movement of water in the liquid and vapour is represented by Richards' equation with an effective hydraulic conductivity and that (ii the coupling between the soil and the well-mixed atmosphere can be modelled by a boundary layer with a constant transfer resistance. The optimised model fits the data exceptionally well. Remaining deviations during the initial phase of an experiment are thought to be well-understood and are attributed to the onset of the heat flow through the column which compensates the latent heat of evaporation.

  11. Extended liner performance for hydrodynamics and material properties experiments

    CERN Document Server

    Reinovsky, R E

    2001-01-01

    Summary form only given, as follows. Over the last few years a new application for high performance pulsed power, the production of high energy density environments for the study of material properties under extreme conditions and hydrodynamics in complex geometries has joined the traditional family of radiation source applications. The newly commissioned Atlas pulsed power system at Los Alamos has replaced its predecessor, Pegasus, and joined the Shiva Star system at AFRL, Albuquerque and a variety of flux compression systems, principally at the All Russian Scientific Research Institute of Experimental Physics (VNIIEF) as ultra high current drivers for the high precision, magnetically imploded, near-solid density liner that is used to create the needed environments. Three families of experiments: the production of ultra strong shocks (>10 Mbar), the production of strongly coupled plasmas by liner compression of an initially dense plasma of a few eV temperature, and the compression of a magnetized plasma for ...

  12. Modeling material-degradation-induced elastic property of tissue engineering scaffolds.

    Science.gov (United States)

    Bawolin, N K; Li, M G; Chen, X B; Zhang, W J

    2010-11-01

    The mechanical properties of tissue engineering scaffolds play a critical role in the success of repairing damaged tissues/organs. Determining the mechanical properties has proven to be a challenging task as these properties are not constant but depend upon time as the scaffold degrades. In this study, the modeling of the time-dependent mechanical properties of a scaffold is performed based on the concept of finite element model updating. This modeling approach contains three steps: (1) development of a finite element model for the effective mechanical properties of the scaffold, (2) parametrizing the finite element model by selecting parameters associated with the scaffold microstructure and/or material properties, which vary with scaffold degradation, and (3) identifying selected parameters as functions of time based on measurements from the tests on the scaffold mechanical properties as they degrade. To validate the developed model, scaffolds were made from the biocompatible polymer polycaprolactone (PCL) mixed with hydroxylapatite (HA) nanoparticles and their mechanical properties were examined in terms of the Young modulus. Based on the bulk degradation exhibited by the PCL/HA scaffold, the molecular weight was selected for model updating. With the identified molecular weight, the finite element model developed was effective for predicting the time-dependent mechanical properties of PCL/HA scaffolds during degradation.

  13. Chitosan fibers with improved biological and mechanical properties for tissue engineering applications.

    Science.gov (United States)

    Albanna, Mohammad Z; Bou-Akl, Therese H; Blowytsky, Oksana; Walters, Henry L; Matthew, Howard W T

    2013-04-01

    The low mechanical properties of hydrogel materials such as chitosan hinder their broad utility for tissue engineering applications. Previous research efforts improved the mechanical properties of chitosan fiber through chemical and physical modifications; however, unfavorable toxicity effects on cells were reported. In this paper, we report the preparation of chitosan fibers with improved mechanical and biocompatibility properties. The structure-property relationships of extruded chitosan fibers were explored by varying acetic acid (AA) concentration, ammonia concentration, annealing temperature and degree of heparin crosslinking. Results showed that optimizing AA concentration to 2vol% improved fiber strength and stiffness by 2-fold. Extruding chitosan solution into 25wt% of ammonia solution reduced fiber diameters and improved fiber strength by 2-fold and stiffness by 3-fold, due to an increase in crystallinity as confirmed by XRD. Fiber annealing further reduced fiber diameter and improved fiber strength and stiffness as temperature increased. Chitosan fibers crosslinked with heparin had increased diameter but lower strength and stiffness properties and higher breaking strain values. When individual parameters were combined, further improvement in fiber mechanical properties was achieved. All mechanically improved fibers and heparin crosslinked fibers promoted valvular interstitial cells (VIC) attachment and growth over 10 day cultures. Our results demonstrate the ability to substantially improve the mechanical properties of chitosan fibers without adversely affecting their biological properties. The investigated treatments offer numerous advantages over previous physical/chemical modifications and thus are expected to expand the utility of chitosan fibers with tunable mechanical properties in various tissue engineering applications. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Transferring experience labs for production engineering students to universities in newly industrialized countries

    Science.gov (United States)

    Leiden, A.; Posselt, G.; Bhakar, V.; Singh, R.; Sangwan, K. S.; Herrmann, C.

    2018-01-01

    The Indian economy is one of the fastest growing economies in the world and the demand for the skilled engineers is increasing. Subsequently the Indian education sector is growing to provide the necessary number of skilled engineers. Current Indian engineering graduates have broad theoretical background but lack in methodological, soft and practical skills. To bridge this gap, the experience lab ideas from the engineering education at “Die Lernfabrik” (learning factory) of the Technische Universität Braunschweig (TU Braunschweig) is transferred to the Birla Institute of Technology and Science in Pilani (BITS Pilani), India. This Lernfabrik successfully strengthened the methodological, soft and practical skills of the TU Braunschweig production-engineering graduates. The target group is discrete manufacturing education with focusing on energy and resource efficiency as well as cyber physical production systems. As the requirements of industry and academia in India differs from Germany, the transfer of the experience lab to the Indian education system needs special attention to realize a successful transfer project. This publication provides a unique approach to systematically transfer the educational concept in Learning Factory from a specific university environment to a different environment in a newly industrialized country. The help of a bilateral university driven practice partnership between the two universities creates a lighthouse for the Indian university environment.

  15. Correlation between electrical, mechanical and chemical properties of fresh and used aircraft engine oils

    Science.gov (United States)

    Gajewski, Juliusz B.; Głogowski, Marek J.; Paszkowski, Maciej; Czarnik-Matusewicz, Bogusława

    2011-06-01

    In this paper the results are presented of measurements of electrical, mechanical and chemical properties of fresh and used aircraft engine oils. Oils were used in a four-stroke aircraft engine and their samples were taken after the 50-hour work of the engine. The resistivity, permittivity and viscosity of oils were measured as a function of temperature. Additionally, some measurements of the absorbance spectra and size of particles contained in the oils were carried out. The significant reduction in the resistivity of the used Total oil was observed. The relative permittivity of both used oils was slightly increased. The oil's relative viscosity depends on temperature of oil and given time that elapsed from the very first moment when the shear force was applied in a rheometer. The results obtained allowed one to identify more precisely the chemical and physico-chemical interactions occurring in the tested samples, as compared with a typical infrared spectroscopy.

  16. Correlation between electrical, mechanical and chemical properties of fresh and used aircraft engine oils

    International Nuclear Information System (INIS)

    Gajewski, Juliusz B; Glogowski, Marek J; Paszkowski, Maciej; Czarnik-Matusewicz, Boguslawa

    2011-01-01

    In this paper the results are presented of measurements of electrical, mechanical and chemical properties of fresh and used aircraft engine oils. Oils were used in a four-stroke aircraft engine and their samples were taken after the 50-hour work of the engine. The resistivity, permittivity and viscosity of oils were measured as a function of temperature. Additionally, some measurements of the absorbance spectra and size of particles contained in the oils were carried out. The significant reduction in the resistivity of the used Total oil was observed. The relative permittivity of both used oils was slightly increased. The oil's relative viscosity depends on temperature of oil and given time that elapsed from the very first moment when the shear force was applied in a rheometer. The results obtained allowed one to identify more precisely the chemical and physico-chemical interactions occurring in the tested samples, as compared with a typical infrared spectroscopy.

  17. Manufacturing of hydrogel biomaterials with controlled mechanical properties for tissue engineering applications.

    Science.gov (United States)

    Vedadghavami, Armin; Minooei, Farnaz; Mohammadi, Mohammad Hossein; Khetani, Sultan; Rezaei Kolahchi, Ahmad; Mashayekhan, Shohreh; Sanati-Nezhad, Amir

    2017-10-15

    Hydrogels have been recognized as crucial biomaterials in the field of tissue engineering, regenerative medicine, and drug delivery applications due to their specific characteristics. These biomaterials benefit from retaining a large amount of water, effective mass transfer, similarity to natural tissues and the ability to form different shapes. However, having relatively poor mechanical properties is a limiting factor associated with hydrogel biomaterials. Controlling the biomechanical properties of hydrogels is of paramount importance. In this work, firstly, mechanical characteristics of hydrogels and methods employed for characterizing these properties are explored. Subsequently, the most common approaches used for tuning mechanical properties of hydrogels including but are not limited to, interpenetrating polymer networks, nanocomposites, self-assembly techniques, and co-polymerization are discussed. The performance of different techniques used for tuning biomechanical properties of hydrogels is further compared. Such techniques involve lithography techniques for replication of tissues with complex mechanical profiles; microfluidic techniques applicable for generating gradients of mechanical properties in hydrogel biomaterials for engineering complex human tissues like intervertebral discs, osteochondral tissues, blood vessels and skin layers; and electrospinning techniques for synthesis of hybrid hydrogels and highly ordered fibers with tunable mechanical and biological properties. We finally discuss future perspectives and challenges for controlling biomimetic hydrogel materials possessing proper biomechanical properties. Hydrogels biomaterials are essential constituting components of engineered tissues with the applications in regenerative medicine and drug delivery. The mechanical properties of hydrogels play crucial roles in regulating the interactions between cells and extracellular matrix and directing the cells phenotype and genotype. Despite

  18. Transient Mathematical Modeling for Liquid Rocket Engine Systems: Methods, Capabilities, and Experience

    Science.gov (United States)

    Seymour, David C.; Martin, Michael A.; Nguyen, Huy H.; Greene, William D.

    2005-01-01

    The subject of mathematical modeling of the transient operation of liquid rocket engines is presented in overview form from the perspective of engineers working at the NASA Marshall Space Flight Center. The necessity of creating and utilizing accurate mathematical models as part of liquid rocket engine development process has become well established and is likely to increase in importance in the future. The issues of design considerations for transient operation, development testing, and failure scenario simulation are discussed. An overview of the derivation of the basic governing equations is presented along with a discussion of computational and numerical issues associated with the implementation of these equations in computer codes. Also, work in the field of generating usable fluid property tables is presented along with an overview of efforts to be undertaken in the future to improve the tools use for the mathematical modeling process.

  19. “Girl Power”: Gendered Academic and Workplace Experiences of College Women in Engineering

    Directory of Open Access Journals (Sweden)

    Kathleen N. Smith

    2018-01-01

    Full Text Available Women in engineering continue to experience bias in the field. This constructivist case study uses feminist theory to examine the gendered experiences of graduating senior women engineering students in academic and workplace environments. In each setting we identified three subthemes; in academia: “I don’t think my education is any different,” “Being underestimated constantly,” and “You don’t want to be seen as getting advantages”; in the workplace: “Oh, you’re a girl,” “There’s a lot of sexism,” and Benefits of “girl power.” Overall, findings indicate that women experience bias in both settings, often via implicit bias in academia and with instances of implicit bias, sexism, and sexual harassment occurring even more often in the workplace through internship experiences. The article concludes with suggestions for practice, future research, and strategies to create supportive academic and workplace experiences and environments for women engineers.

  20. Construction of experience feedback system for equipment supervision in nuclear engineering

    International Nuclear Information System (INIS)

    Zou Pingguo; Zhang Liying; Zhang Wenzhong

    2009-01-01

    Based on the analysis of the experience sources on equipment supervision in nuclear engineering, the details of the organization principle, working flow, and report requirement for the experience feedback system are introduced. The function range and its roll in the experience feedback system of the nuclear authority, nuclear power plant owners and equipment supervision organizations are illustrated. The standardization working requirements in the information gathering, analyzing, feedback and tracking process, and the characteristics and form of the incident report and feedback report are proposed. It emphasizes that the method for combined analysis of one significant incident and the whole incidents shall be adopted in the information analysis, and the experience feedback shall be considered in the development of equipment supervision technique and the equipment manufacturing, thus to maximize the use of experience feedback information to improve the pertinency and effectiveness of the experience feedback system. (authors)

  1. Hydrate-Bearing Clayey Sediments: Morphology, Physical Properties, Production and Engineering/Geological Implications

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Sheng [Georgia Tech Research Corporation, Atlanta, GA (United States); Santamarina, J. Carlos [King Abdulaziz Univ., Jeddah (Saudi Arabia)

    2017-12-30

    Fine-grained sediments host more than 90 percent of global gas hydrate accumulation. However, hydrate formation in clay-dominated sediments is less understood and characterized than other types of hydrate occurrence. There is an inadequate understanding of hydrate formation mechanisms, segregation structures, hydrate lens topology, system connectivity, and physical macro-scale properties of clay-dominated hydrate-bearing sediments. This situation hinders further analyses of the global carbon budget as well as engineering challenges/solutions related to hydrate instability and production. This project studies hydrate-bearing clay-dominated sediments with emphasis on the enhanced fundamental understanding of hydrate formation and resulting morphology, the development laboratory techniques to emulate natural hydrate formations, the assessment of analytical tools to predict physical properties, the evaluation of engineering and geological implications, and the advanced understanding of gas production potential from finegrained sediments.

  2. 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.

  3. Passaged adult chondrocytes can form engineered cartilage with functional mechanical properties: a canine model.

    Science.gov (United States)

    Ng, Kenneth W; Lima, Eric G; Bian, Liming; O'Conor, Christopher J; Jayabalan, Prakash S; Stoker, Aaron M; Kuroki, Keiichi; Cook, Cristi R; Ateshian, Gerard A; Cook, James L; Hung, Clark T

    2010-03-01

    It was hypothesized that previously optimized serum-free culture conditions for juvenile bovine chondrocytes could be adapted to generate engineered cartilage with physiologic mechanical properties in a preclinical, adult canine model. Primary or passaged (using growth factors) adult chondrocytes from three adult dogs were encapsulated in agarose, and cultured in serum-free media with transforming growth factor-beta3. After 28 days in culture, engineered cartilage formed by primary chondrocytes exhibited only small increases in glycosaminoglycan content. However, all passaged chondrocytes on day 28 elaborated a cartilage matrix with compressive properties and glycosaminoglycan content in the range of native adult canine cartilage values. A preliminary biocompatibility study utilizing chondral and osteochondral constructs showed no gross or histological signs of rejection, with all implanted constructs showing excellent integration with surrounding cartilage and subchondral bone. This study demonstrates that adult canine chondrocytes can form a mechanically functional, biocompatible engineered cartilage tissue under optimized culture conditions. The encouraging findings of this work highlight the potential for tissue engineering strategies using adult chondrocytes in the clinical treatment of cartilage defects.

  4. Effect of plasma spraying modes on material properties of internal combustion engine cylinder liners

    Science.gov (United States)

    Timokhova, O. M.; Burmistrova, O. N.; Sirina, E. A.; Timokhov, R. S.

    2018-03-01

    The paper analyses different methods of remanufacturing worn-out machine parts in order to get the best performance characteristics. One of the most promising of them is a plasma spraying method. The mathematical models presented in the paper are intended to anticipate the results of plasma spraying, its effect on the properties of the material of internal combustion engine cylinder liners under repair. The experimental data and research results have been computer processed with Statistica 10.0 software package. The pare correlation coefficient values (R) and F-statistic criterion are given to confirm the statistical properties and adequacy of obtained regression equations.

  5. Dynamic and Thermodynamic Properties of a CA Engine with Non-Instantaneous Adiabats

    Directory of Open Access Journals (Sweden)

    Ricardo T. Paéz-Hernández

    2017-11-01

    Full Text Available This paper presents an analysis of a Curzon and Alhborn thermal engine model where both internal irreversibilities and non-instantaneous adiabatic branches are considered, operating with maximum ecological function and maximum power output regimes. Its thermodynamic properties are shown, and an analysis of its local dynamic stability is performed. The results derived are compared throughout the work with the results obtained previously for a case in which the adiabatic branches were assumed as instantaneous. The results indicate a better performance for thermodynamic properties in the model with instantaneous adiabatic branches, whereas there is an improvement in robustness in the case where non-instantaneous adiabatic branches are considered.

  6. Influence of polyolefin fibers on the engineering properties of cement-based composites containing silica fume

    International Nuclear Information System (INIS)

    Han, Ta-Yuan; Lin, Wei-Ting; Cheng, An; Huang, Ran; Huang, Chin-Cheng

    2012-01-01

    Highlights: ► Experimental study is focus on the engineering properties of cement-based composites. ► Different mixes containing fiber and silica fume proportions have been tested. ► The influence of different mixes on the engineering properties has been discussed. ► The properties are included strength, ductility, permeability and microstructure. -- Abstract: This study evaluated the mechanical properties of cement-based composites produced with added polyolefin fibers and silica fume. Material variables included the water-cementitious ratio, the dosage of silica fume, and the length and dosage of polyolefin fiber. Researchers conducted tests on compressive strength, splitting tensile strength, direct tensile strength, resistivity, rapid chloride penetration, and initial surface absorption, and performed microscopic observation. Test results indicate that the specimens containing silica fume have higher compressive strength than the control and specimen made with fibers. The specimens with polyolefin fiber and silica fume have considerably higher tensile strength and ductility than the control and specimens made with silica fume. The specimens containing silica fume and polyolefin fiber demonstrated better resistance to chloride penetration than composites with polyolefin fiber or silica fume. For a given volume fraction, short polyolefin fiber performs better than its long counterpart in improving the properties of concrete. Specimens containing silica fume demonstrated a significant increase in resistivity and decrease in the total charge passed and absorption. Scanning electron microscopy illustrates that the polyolefin fiber acts to arrest the propagation of internal cracks.

  7. Experience in the Education of Engineers from Vietnam in the Faculty of Mining and Geoengineering AGH

    Science.gov (United States)

    Cała, Marek; Borowski, Marek

    2018-03-01

    The AGH University of Science and Technology collaborates closely with other universities, economic units, governmental and local administrative bodies. International cooperation plays a very important role in the academic research. The AGH University of Science and Technology has signed many collaboration agreements. They aim at multidimensional cooperation in the fields of education and academic research. AGH UST has always focused on collaboration with business and industry. In recent years, the global economy is undergoing massive transformations, what creates new challenges to companies and educational institutions that cater to the needs of industry. The expansion of business enterprises is largely dependent on their employees' expertise, skills and levels of competence. Certified engineers are provided by universities. Therefore, the qualifications of the graduates are determined by the curriculum and teaching methods, as well as the available educational and research facilities. Of equal importance is the qualified academic staff. Human activities in the field of engineering require finding solutions to problems of various nature and magnitude. An engineer's work consists in the design, construction, modification and maintenance of useful devices, processes and systems, using scientific and technical knowledge. In order to design complex engineering solutions, an engineer uses his imagination, experience, analytical skills, logical reasoning and makes conscious use of his knowledge. At the Faculty of Mining and Geoengineering of the AGH University of Science and Technology in Cracow, 15 engineers from Vietnam are studying Mining and Geology at the second-cycle studies (specialization: mine ventilation). The solutions proposed in the field of the engineers' education guarantee that foreign students gain both engineering knowledge and problem-solving skills. Therefore, the study programme was complemented by a series of practical aspects.

  8. Simulation and experiment for oxygen-enriched combustion engine using liquid oxygen to solidify CO2

    Science.gov (United States)

    Liu, Yongfeng; Jia, Xiaoshe; Pei, Pucheng; Lu, Yong; Yi, Li; Shi, Yan

    2016-01-01

    For capturing and recycling of CO2 in the internal combustion engine, Rankle cycle engine can reduce the exhaust pollutants effectively under the condition of ensuring the engine thermal efficiency by using the techniques of spraying water in the cylinder and optimizing the ignition advance angle. However, due to the water spray nozzle need to be installed on the cylinder, which increases the cylinder head design difficulty and makes the combustion conditions become more complicated. In this paper, a new method is presented to carry out the closing inlet and exhaust system for internal combustion engines. The proposed new method uses liquid oxygen to solidify part of cooled CO2 from exhaust system into dry ice and the liquid oxygen turns into gas oxygen which is sent to inlet system. The other part of CO2 is sent to inlet system and mixed with oxygen, which can reduce the oxygen-enriched combustion detonation tendency and make combustion stable. Computing grid of the IP52FMI single-cylinder four-stroke gasoline-engine is established according to the actual shape of the combustion chamber using KIVA-3V program. The effects of exhaust gas recirculation (EGR) rate are analyzed on the temperatures, the pressures and the instantaneous heat release rates when the EGR rate is more than 8%. The possibility of enclosing intake and exhaust system for engine is verified. The carbon dioxide trapping device is designed and the IP52FMI engine is transformed and the CO2 capture experiment is carried out. The experimental results show that when the EGR rate is 36% for the optimum EGR rate. When the liquid oxygen of 35.80-437.40 g is imported into the device and last 1-20 min, respectively, 21.50-701.30 g dry ice is obtained. This research proposes a new design method which can capture CO2 for vehicular internal combustion engine.

  9. The Effects of Spent Engine Oil on Soil Properties and Growth of ...

    African Journals Online (AJOL)

    The effect of spent engine oil (SEO) on soil properties and growth of maize (Zea mays L.) was investigated. Five treatments (0.0, 0.2, 0.4, 0.6 and 0.8 l/kg) of the spent oil were applied to soil in perforated poly bags with maize stands at four weeks after sowing. Soil analysis showed that SEO had no effect on both the pH and ...

  10. Operation experiences of landfill gas engines; Motorer foer deponigas - Tillgaenglighet och drifterfarenheter

    Energy Technology Data Exchange (ETDEWEB)

    Dejfors, Charlotte; Grimberger, Goeran [AaF-Energikonsult Stockholm AB (Sweden)

    2000-06-01

    The gas that is obtained from landfilled waste is produced by bacteria that digest organic material in an anaerobic environment. Landfill gas consists mainly of methane, carbon dioxide and water vapour. It may be used either as auxiliary fuel in boilers close to the landfill or to generate electricity by means of a gas engine. Several plants where landfill gas is used in gas engines have had serious problems, a. o. with burned exhaust valves. These problems may occur already after a short period of operation, which influences the profitability. The purposes of the project reported were to collect operational experience in Sweden with engines using landfill gas as fuel, to identify which problems there are and which actions or improvements have been implemented in order to correct for these problems. Today, there are 9 facilities where landfill gas is used to fuel a total of 13 gas engines. In addition, there is an engine in Goeteborg which has scarcely been in operation after its installation because there is not enough gas. Contact has been taken with all these facilities. Many have pointed out that the gas engines are sensitive in the vicinity of maximum load, where the control system requires an even gas flow and a stable composition of the gas. A counter-measure in the facilities is to avoid running the engine at full load. All engines are equipped with a lean-NO{sub x} system in order to minimise NO{sub x} emissions. Many have remarked that the lean-NO{sub x} system shuts the engine off when emissions exceed the allowed limits. There is a consensus that spark plugs and ignition cables have created operational problems. These have been changed more frequently than originally expected. Another problem, which has caused operational problems and a need for maintenance, is deposits mainly in the combustion chamber, in valves and cylinder heads. Deposits and high exhaust gas temperature have led to burnt exhaust gas valves and cylinder heads on half of the engines

  11. An assessment of gas impact on geological repository. Methodology and material property of gas migration analysis in engineered barrier system

    International Nuclear Information System (INIS)

    Yamamoto, Mikihiko; Mihara, Morihiro; Ooi, Takao

    2004-01-01

    Gas production in a geological repository has potential hazard, as overpressurisation and enhanced release of radionuclides. Amongst data needed for assessment of gas impact, gas migration properties of engineered barriers, focused on clayey and cementitious material, was evaluated in this report. Gas injection experiments of saturated bentonite sand mixture, mortar and cement paste were carried out. In the experiments, gas entry phenomenon and gas outflow rate were observed for these materials. Based on the experimental results, two-phase flow parameters were evaluated quantitatively. A conventional continuum two-phase flow model, which is only practically used multidimensional multi-phase flow model, was applied to fit the experimental results. The simulation results have been in good agreement with the gas entry time and the outflow flux of gas and water observed in the experiments. It was confirmed that application of the continuum two-phase flow model to gas migration in cementitious materials provides sufficient degree of accuracy for assessment of repository performance. But, for sand bentonite mixture, further extension of basic two-phase flow model is needed especially for effect of stress field. Furthermore, gas migration property of other barrier materials, including rocks, but long-term gas injection test, clarification of influence of chemicals environment and large-scale gas injection test is needed for multi-barrier assessment tool development and their verification. (author)

  12. ThermoData Engine (TDE): software implementation of the dynamic data evaluation concept. 5. Experiment planning and product design.

    Science.gov (United States)

    Diky, Vladimir; Chirico, Robert D; Kazakov, Andrei F; Muzny, Chris D; Magee, Joseph W; Abdulagatov, Ilmutdin; Kang, Jeong Won; Kroenlein, Kenneth; Frenkel, Michael

    2011-01-24

    ThermoData Engine (TDE) is the first full-scale software implementation of the dynamic data evaluation concept, as reported recently in this journal. In the present paper, we describe development of an algorithmic approach to assist experiment planning through assessment of the existing body of knowledge, including availability of experimental thermophysical property data, variable ranges studied, associated uncertainties, state of prediction methods, and parameters for deployment of prediction methods and how these parameters can be obtained using targeted measurements, etc., and, indeed, how the intended measurement may address the underlying scientific or engineering problem under consideration. A second new feature described here is the application of the software capabilities for aid in the design of chemical products through identification of chemical systems possessing desired values of thermophysical properties within defined ranges of tolerance. The algorithms and their software implementation to achieve this are described. Finally, implementation of a new data validation and weighting system is described for vapor-liquid equilibrium (VLE) data, and directions for future enhancements are outlined.

  13. Progreen online engineering diploma in the Middle East: assessment of the educational experience

    Science.gov (United States)

    Baytiyeh, Hoda

    2018-03-01

    Little is known about the status of online learning in the Middle East. This study investigates educational experiences of engineers enrolled in the new joint online ProGreen diploma programme offered by three universities, two in Lebanon and one in Egypt. Forty-eight working engineers responded to an online survey based on the three components of the community of inquiry model: social presence, teaching presence, and cognitive presence. Exploratory factor analysis identified five factors: sense of belonging, self-directedness, self-actualisation, interaction, and instructional guidance. The findings showed that sense of belonging was the factor engineers rated highest but it did not correlate with instructional guidance. However, instructional guidance highly correlated with self-directedness and self-actualisation.

  14. Moral responsibility, technology, and experiences of the tragic: from Kierkegaard to offshore engineering.

    Science.gov (United States)

    Coeckelbergh, Mark

    2012-03-01

    The standard response to engineering disasters like the Deepwater Horizon case is to ascribe full moral responsibility to individuals and to collectives treated as individuals. However, this approach is inappropriate since concrete action and experience in engineering contexts seldom meets the criteria of our traditional moral theories. Technological action is often distributed rather than individual or collective, we lack full control of the technology and its consequences, and we lack knowledge and are uncertain about these consequences. In this paper, I analyse these problems by employing Kierkegaardian notions of tragedy and moral responsibility in order to account for experiences of the tragic in technological action. I argue that ascription of responsibility in engineering contexts should be sensitive to personal experiences of lack of control, uncertainty, role conflicts, social dependence, and tragic choice. I conclude that this does not justify evading individual and corporate responsibility, but inspires practices of responsibility ascription that are less 'harsh' on those directly involved in technological action, that listen to their personal experiences, and that encourage them to gain more knowledge about what they are doing. © The Author(s) 2010. This article is published with open access at Springerlink.com

  15. Experience with Aero- and Fluid-Dynamic Testing for Engineering and CFD Validation

    Science.gov (United States)

    Ross, James C.

    2016-01-01

    Ever since computations have been used to simulate aerodynamics the need to ensure that the computations adequately represent real life has followed. Many experiments have been performed specifically for validation and as computational methods have improved, so have the validation experiments. Validation is also a moving target because computational methods improve requiring validation for the new aspect of flow physics that the computations aim to capture. Concurrently, new measurement techniques are being developed that can help capture more detailed flow features pressure sensitive paint (PSP) and particle image velocimetry (PIV) come to mind. This paper will present various wind-tunnel tests the author has been involved with and how they were used for validation of various kinds of CFD. A particular focus is the application of advanced measurement techniques to flow fields (and geometries) that had proven to be difficult to predict computationally. Many of these difficult flow problems arose from engineering and development problems that needed to be solved for a particular vehicle or research program. In some cases the experiments required to solve the engineering problems were refined to provide valuable CFD validation data in addition to the primary engineering data. All of these experiments have provided physical insight and validation data for a wide range of aerodynamic and acoustic phenomena for vehicles ranging from tractor-trailers to crewed spacecraft.

  16. The reliability of structural systems operating at high temperature: Replacing engineering judgement with operational experience

    International Nuclear Information System (INIS)

    Chevalier, M.J.; Smith, D.J.; Dean, D.W.

    2012-01-01

    Deterministic assessments are used to assess the integrity of structural systems operating at high temperature by providing a lower bound lifetime prediction, requiring considerable engineering judgement. However such a result may not satisfy the structural integrity assessment purpose if the results are overly conservative or conversely plant observations (such as failures) could undermine the assessment result if observed before the lower bound lifetime. This paper develops a reliability methodology for high temperature assessments and illustrates the impact and importance of managing the uncertainties within such an analysis. This is done by separating uncertainties into three classifications; aleatory uncertainty, quantifiable epistemic uncertainty and unquantifiable epistemic uncertainty. The result is a reliability model that can predict the behaviour of a structural system based upon plant observations, including failure and survival data. This can be used to reduce the over reliance upon engineering judgement which is prevalent in deterministic assessments. Highlights: ► Deterministic assessments are shown to be heavily reliant upon engineering judgment. ► Based upon the R5 procedure, a reliability model for a structural system is developed. ► Variables must be classified as either aleatory or epistemic to model their impact on reliability. ► Operation experience is then used to reduce reliance upon engineering judgment. ► This results in a model which can predict system behaviour and learn from operational experience.

  17. Engineering aspects of the experiment and results of animal tests. [Apollo 17 Biological Cosmic Ray Experiment

    Science.gov (United States)

    Look, B. C.; Tremor, J. W.; Barrows, W. F.; Zabower, H. R.; Suri, K.; Park, E. G., Jr.; Durso, J. A.; Leon, H. A.; Haymaker, W.; Lindberg, R. G.

    1975-01-01

    A closed passive system independent of support from the spacecraft or its crew was developed to house five pocket mice for their flight on Apollo XVII. The reaction of potassium superoxide with carbon dioxide and water vapor to produce oxygen provided a habitable atmosphere within the experiment package. The performance of the system and the ability of the mice to survive the key preflight tests gave reasonable assurance that the mice would also withstand the Apollo flight.-

  18. Gas reactor and associated nuclear experience in the UK relevant to high temperature reactor engineering

    International Nuclear Information System (INIS)

    Beech, D.J.; May, R.

    2000-01-01

    In the UK, the NNC played a leading role in the design and build of all of the UK's commercial magnox reactors and advanced gas-cooled reactors (AGRs). It was also involved in the DRAGON project and was responsible for producing designs for large scale HTRs and other gas reactor designs employing helium and carbon dioxide coolants. This paper addresses the gas reactor experience and its relevance to the current HTR designs under development which use helium as the coolant, through the consideration of a representative sample of the issues addressed in the UK by the NNC in support of the AGR and other reactor programmes. Modern HTR designs provide unique engineering challenges. The success of the AGR design, reflected in the extended lifetimes agreed upon by the licensing authorities at many stations, indicates that these challenges can be successfully overcome. The UK experience is unique and provides substantial support to future gas reactor and high temperature engineering studies. (authors)

  19. A Remote and Virtual Lab with Experiments for Secondary Education, Engineering and Lifelong Learning Courses

    Directory of Open Access Journals (Sweden)

    Alberto Cardoso

    2012-03-01

    Full Text Available The Information and Communication Technology tools are nowadays invaluable to support e-learning and b-learning programs. The Remote and Virtual Laboratory in development at the Department of Informatics Engineering of the University of Coimbra (Portugal, RVL@DEI-UC, is a web-based platform that allows users to perform a large set of experiments in different areas and contexts, such as in education or training. This paper aims to describe the inherent potential of this platform in secondary education, engineering and lifelong learning courses. The conceptualization, architecture and implementation of the web platform for real and virtual experiments, which is remotely accessed using the Internet, are presented and the relevance of the lab’s integration in an intelligent tutoring system is also highlighted, mainly in what regards the requirements of adaptation and customization to different users’ profile in different learning contexts.

  20. Incorrect results in software engineering experiments: How to improve research practices

    OpenAIRE

    Jørgensen, Magne; Dybå, Tore; Liestøl, Knut; Sjøberg, Dag

    2016-01-01

    Context The trustworthiness of research results is a growing concern in many empirical disciplines. Aim The goals of this paper are to assess how much the trustworthiness of results reported in software engineering experiments is affected by researcher and publication bias, given typical statistical power and significance levels, and to suggest improved research practices. Method First, we conducted a small-scale survey to document the presence of researcher and publication biases in software...

  1. Development of Chitosan Scaffolds with Enhanced Mechanical Properties for Intestinal Tissue Engineering Applications.

    Science.gov (United States)

    Zakhem, Elie; Bitar, Khalil N

    2015-10-13

    Massive resections of segments of the gastrointestinal (GI) tract lead to intestinal discontinuity. Functional tubular replacements are needed. Different scaffolds were designed for intestinal tissue engineering application. However, none of the studies have evaluated the mechanical properties of the scaffolds. We have previously shown the biocompatibility of chitosan as a natural material in intestinal tissue engineering. Our scaffolds demonstrated weak mechanical properties. In this study, we enhanced the mechanical strength of the scaffolds with the use of chitosan fibers. Chitosan fibers were circumferentially-aligned around the tubular chitosan scaffolds either from the luminal side or from the outer side or both. Tensile strength, tensile strain, and Young's modulus were significantly increased in the scaffolds with fibers when compared with scaffolds without fibers. Burst pressure was also increased. The biocompatibility of the scaffolds was maintained as demonstrated by the adhesion of smooth muscle cells around the different kinds of scaffolds. The chitosan scaffolds with fibers provided a better candidate for intestinal tissue engineering. The novelty of this study was in the design of the fibers in a specific alignment and their incorporation within the scaffolds.

  2. Exclusion and symbolic violence in the educational experience of female engineering students

    Directory of Open Access Journals (Sweden)

    Cecilia Ortmann

    2016-11-01

    Full Text Available On the initial problem the gender gap in enrollment in engineering careers, this paper analyzes the link between masculinity attribution of science and technology, and the perception of symbolic violence in the everyday experience of women trying to study these careers. From testimonies and narrations, I explore the experiences of students to identify assumptions about how the subjects and formed in these areas and should be, as well as the possibilities, capabilities and limitations that are assigned to them, contributing from the empiria to a conceptualization of modes of exclusion and delegitimization that support the formation of a strongly masculinized scene.

  3. THE INFLUENCE OF THE INSTALLATION METHOD ON THE SELECTED PROPERTIES OF BIODEGRADABLE GEOTEXTILES USED IN ENVIRONMENTAL ENGINEERING

    Directory of Open Access Journals (Sweden)

    Joanna Beata Grzybowska-Pietras

    2017-06-01

    Full Text Available In the engineering constructions there are used biodegradable geotextiles, that are performing primarily a function of surface anti-erosion protection. Their biodegradability supports the development of vegetation, and protects the surface of the slope from the moment of installation in the ground. In order to achieve this functionality there are used mainly biononwovens and woven fabrics made of natiral fibers. In the paper there are presented results of studies on the effect of the instalation of the biononwoven (Maliwatt type with grass seeds applied in real conditions at a specified time (from November to June, on the selected physical, mechanical and hydraulic properties , and the development of vegetation (grasses. The experiment adopted two versions of instalation of nonwovens. In the first case geotextile was mounted directly on the ground, in the second additionally have been covered with a layer of native soil.

  4. Fuel properties and engine performance of biodiesel from waste cooking oil collected in Dhaka city

    Science.gov (United States)

    Islam, R. B.; Islam, R.; Uddin, M. N.; Ehsan, Md.

    2016-07-01

    Waste cooking oil can be a potential source of biodiesel that has least effect on the edible oil consumption. Increasing number of hotel-restaurants and more active monitoring by health authorities have increased the generation of waste cooking oil significantly in densely populated cities like Dhaka. If not used or disposed properly, waste cooking oil itself may generate lot of environmental issues. In this work, waste cooking oils from different restaurants within Dhaka City were collected and some relevant properties of these waste oils were measured. Based on the samples studied one with the highest potential as biodiesel feed was identified and processed for engine performance. Standard trans-esterification process was used to produce biodiesel from the selected waste cooking oil. Biodiesel blends of B20 and B40 category were made and tested on a single cylinder direct injection diesel engine. Engine performance parameters included - bhp, bsfc and exhaust emission for rated and part load conditions. Results give a quantitative assessment of the potential of using biodiesel from waste cooking oil as fuel for diesel engines in Bangladesh.

  5. Laboratory assessment of the influence of the proportion of waste foundry sand on the geotechnical engineering properties of clayey soils

    CSIR Research Space (South Africa)

    Mgangira, Martin B

    2006-01-01

    Full Text Available Soil improvement can be achieved through mechanical stabilisation using industrial byproducts. Clayey soils were blended with waste foundry sand to examine its influence on the geotechnical engineering properties of the soils. The waste foundry sand...

  6. In-cylinder visualization and engine out emissions from CI to PPC for fuels with different properties

    KAUST Repository

    An, Yanzhao; Vallinayagam, R.; Vedharaj, S.; Masurier, Jean-Baptiste; Najafabadi, Mohammad Izadi; Somers, Bart; Johansson, Bengt

    2018-01-01

    This study investigated the transition from conventional Compression Ignition (CI) to Partially Premixed Combustion (PPC) in an optical engine for fuels with differing properties. Combustion stratification and emissions were measured with diesel

  7. Human Factors Engineering (HFE) insights for advanced reactors based upon operating experience

    International Nuclear Information System (INIS)

    Higgins, J.; Nasta, K.

    1997-01-01

    The NRC Human Factors Engineering Program Review Model (HFE PRM, NUREG-0711) was developed to support a design process review for advanced reactor design certification under 10CFR52. The HFE PRM defines ten fundamental elements of a human factors engineering program. An Operating Experience Review (OER) is one of these elements. The main purpose of an OER is to identify potential safety issues from operating plant experience and ensure that they are addressed in a new design. Broad-based experience reviews have typically been performed in the past by reactor designers. For the HFE PRM the intent is to have a more focussed OER that concentrates on HFE issues or experience that would be relevant to the human-system interface (HSI) design process for new advanced reactors. This document provides a detailed list of HFE-relevant operating experience pertinent to the HSI design process for advanced nuclear power plants. This document is intended to be used by NRC reviewers as part of the HFE PRM review process in determining the completeness of an OER performed by an applicant for advanced reactor design certification. 49 refs

  8. Experience in the Education of Engineers from Vietnam in the Faculty of Mining and Geoengineering AGH

    Directory of Open Access Journals (Sweden)

    Cała Marek

    2018-01-01

    Full Text Available The AGH University of Science and Technology collaborates closely with other universities, economic units, governmental and local administrative bodies. International cooperation plays a very important role in the academic research. The AGH University of Science and Technology has signed many collaboration agreements. They aim at multidimensional cooperation in the fields of education and academic research. AGH UST has always focused on collaboration with business and industry. In recent years, the global economy is undergoing massive transformations, what creates new challenges to companies and educational institutions that cater to the needs of industry. The expansion of business enterprises is largely dependent on their employees’ expertise, skills and levels of competence. Certified engineers are provided by universities. Therefore, the qualifications of the graduates are determined by the curriculum and teaching methods, as well as the available educational and research facilities. Of equal importance is the qualified academic staff. Human activities in the field of engineering require finding solutions to problems of various nature and magnitude. An engineer’s work consists in the design, construction, modification and maintenance of useful devices, processes and systems, using scientific and technical knowledge. In order to design complex engineering solutions, an engineer uses his imagination, experience, analytical skills, logical reasoning and makes conscious use of his knowledge. At the Faculty of Mining and Geoengineering of the AGH University of Science and Technology in Cracow, 15 engineers from Vietnam are studying Mining and Geology at the second-cycle studies (specialization: mine ventilation. The solutions proposed in the field of the engineers’ education guarantee that foreign students gain both engineering knowledge and problem-solving skills. Therefore, the study programme was complemented by a series of practical

  9. High School Graphics Experience Influencing the Self-Efficacy of First-Year Engineering Students in an Introductory Engineering Graphics Course

    Science.gov (United States)

    Metraglia, Riccardo; Villa, Valerio; Baronio, Gabriele; Adamini, Riccardo

    2015-01-01

    Today's students enter engineering colleges with different technical backgrounds and prior graphics experience. This may due to their high school of provenience, which can be technical or non-technical. The prior experience affects students' ability in learning and hence their motivation and self-efficacy beliefs. This study intended to evaluate…

  10. Bio-fuels for diesel engines: Experience in Italy and Europe

    International Nuclear Information System (INIS)

    Rocchietta, C.

    1992-01-01

    With the aim of meeting stringent European Communities air pollution regulations, reducing the necessity of petroleum imports and creating new markets for agricultural products, Italy's Ferruzzi-Montedison Group is developing diesel engine fuels derived from vegetable oils. The innovative feature of these fuels, from the environmental protection stand-point, is that they don't contain any sulfur, the main cause of acid rain. This paper provides brief notes of the key chemical-physical properties of these diesel fuels, whose application doesn't require any modifications to diesel engines, and assesses the relative production technologies and commercialization prospects. Reference is made to the results of recent performance tests conducted on buses and taxis

  11. Influence of normal loads and sliding velocities on friction properties of engineering plastics sliding against rough counterfaces

    International Nuclear Information System (INIS)

    Nuruzzaman, D M; Chowdhury, M A; Rahaman, M L; Oumer, A N

    2016-01-01

    Friction properties of plastic materials are very important under dry sliding contact conditions for bearing applications. In the present research, friction properties of engineering plastics such as polytetrafluoroethylene (PTFE) and nylon are investigated under dry sliding contact conditions. In the experiments, PTFE and nylon slide against different rough counterfaces such as mild steel and stainless steel 316 (SS 316). Frictional tests are carried out at low loads 5, 7.5 and 10 N, low sliding velocities 0.5, 0.75 and 1 m/s and relative humidity 70%. The obtained results reveal that friction coefficient of PTFE increases with the increase in normal loads and sliding velocities within the observed range. On the other hand, frictional values of nylon decrease with the increase in normal loads and sliding velocities. It is observed that in general, these polymers show higher frictional values when sliding against SS 316 rather than mild steel. During running-in process, friction coefficient of PTFE and nylon steadily increases with the increase in rubbing time and after certain duration of rubbing, it remains at steady level. At identical operating conditions, the frictional values are significantly different depending on normal load, sliding velocity and material pair. It is also observed that in general, the influence of normal load on the friction properties of PTFE and nylon is greater than that of sliding velocity. (paper)

  12. Chondroprotective supplementation promotes the mechanical properties of injectable scaffold for human nucleus pulposus tissue engineering.

    Science.gov (United States)

    Foss, Berit L; Maxwell, Thomas W; Deng, Ying

    2014-01-01

    A result of intervertebral disc (IVD) degeneration, the nucleus pulposus (NP) is no longer able to withstand applied load leading to pain and disability. The objective of this study is to fabricate a tissue-engineered injectable scaffold with chondroprotective supplementation in vitro to improve the mechanical properties of a degenerative NP. Tissue-engineered scaffolds were fabricated using different concentrations of alginate and calcium chloride and mechanically evaluated. Fabrication conditions were based on structural and mechanical resemblance to the native NP. Chondroprotective supplementation, glucosamine (GCSN) and chondroitin sulfate (CS), were added to scaffolds at concentrations of 0:0µg/mL (0:0-S), 125:100µg/mL (125:100-S), 250:200µg/mL (250:200-S), and 500:400µg/mL (500:400-S), GCSN and CS, respectively. Scaffolds were used to fabricate tissue-engineered constructs through encapsulation of human nucleus pulposus cells (HNPCs). The tissue-engineered constructs were collected at days 1, 14, and 28 for biochemical and biomechanical evaluations. Confocal microscopy showed HNPC viability and rounded morphology over the 28 day period. MTT analysis resulted in significant increases in cell proliferation for each group. Collagen type II ELISA quantification and compressive aggregate moduli (HA) showed increasing trends for both 250:200-S and the 500:400-S groups on Day 28 with significantly greater HA compared to 0:0-S group. Glycosaminoglycan and water content decreased for all groups. Results indicate the increased mechanical properties of the 250:200-S and the 500:400-S was due to production of a functional matrix. This study demonstrated potential for a chondroprotective supplemented injectable scaffold to restore biomechanical function of a degenerative disc through the production of a mechanically functional matrix. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Morphology and Optical Properties of Black-Carbon Particles Relevant to Engine Emissions

    Science.gov (United States)

    Michelsen, H. A.; Bambha, R.; Dansson, M. A.; Schrader, P. E.

    2013-12-01

    Black-carbon particles are believed to have a large influence on climate through direct radiative forcing, reduction of surface albedo of snow and ice in the cryosphere, and interaction with clouds. The optical properties and morphology of atmospheric particles containing black carbon are uncertain, and characterization of black carbon resulting from engines emissions is needed. Refractory black-carbon particles found in the atmosphere are often coated with unburned fuel, sulfuric acid, water, ash, and other combustion by-products and atmospheric constituents. Coatings can alter the optical and physical properties of the particles and therefore change their optical properties and cloud interactions. Details of particle morphology and coating state can also have important effects on the interpretation of optical diagnostics. A more complete understanding of how coatings affect extinction, absorption, and incandescence measurements is needed before these techniques can be applied reliably to a wide range of particles. We have investigated the effects of coatings on the optical and physical properties of combustion-generated black-carbon particles using a range of standard particle diagnostics, extinction, and time-resolved laser-induced incandescence (LII) measurements. Particles were generated in a co-flow diffusion flame, extracted, cooled, and coated with oleic acid. The diffusion flame produces highly dendritic soot aggregates with similar properties to those produced in diesel engines, diffusion flames, and most natural combustion processes. A thermodenuder was used to remove the coating. A scanning mobility particle sizer (SMPS) was used to monitor aggregate sizes; a centrifugal particle mass analyzer (CPMA) was used to measure coating mass fractions, and transmission electron microscopy (TEM) was used to characterize particle morphologies. The results demonstrate important differences in optical measurements between coated and uncoated particles.

  14. Female peer mentors early in college increase women’s positive academic experiences and retention in engineering

    Science.gov (United States)

    Dasgupta, Nilanjana

    2017-01-01

    Scientific and engineering innovation is vital for American competitiveness, quality of life, and national security. However, too few American students, especially women, pursue these fields. Although this problem has attracted enormous attention, rigorously tested interventions outside artificial laboratory settings are quite rare. To address this gap, we conducted a longitudinal field experiment investigating the effect of peer mentoring on women’s experiences and retention in engineering during college transition, assessing its impact for 1 y while mentoring was active, and an additional 1 y after mentoring had ended. Incoming women engineering students (n = 150) were randomly assigned to female or male peer mentors or no mentors for 1 y. Their experiences were assessed multiple times during the intervention year and 1-y postintervention. Female (but not male) mentors protected women’s belonging in engineering, self-efficacy, motivation, retention in engineering majors, and postcollege engineering aspirations. Counter to common assumptions, better engineering grades were not associated with more retention or career aspirations in engineering in the first year of college. Notably, increased belonging and self-efficacy were significantly associated with more retention and career aspirations. The benefits of peer mentoring endured long after the intervention had ended, inoculating women for the first 2 y of college—the window of greatest attrition from science, technology, engineering, and mathematics (STEM) majors. Thus, same-gender peer mentoring for a short period during developmental transition points promotes women’s success and retention in engineering, yielding dividends over time. PMID:28533360

  15. Engineering properties of high and low altitude rice varieties from Kashmir valley at different processing levels

    Directory of Open Access Journals (Sweden)

    Raees Haq

    2016-12-01

    Full Text Available The knowledge of engineering properties such as gravimetrical properties (1,000 grain mass, bulk density, true density, and porosity, dimensional properties (length, width, thickness, aspect ratio, surface area, geometric mean diameter, and sphericity, frictional properties (angle of repose and coefficient of friction, and aerodynamic properties (drag coefficient and terminal velocity are necessary parameters related to machine design for different agricultural process operations such as handling, harvesting, threshing, cleaning, conveying, sorting, drying, processing, and storage. India is a vast country and contributes 20% of the total world’s rice production with cultivars ranging from the scented long grain ones to the sticky short grains. The Kashmir valley cultivates mainly short–medium bold varieties as temperate conditions in the valley are not suitable for the cultivation of long grain scented basmati rice. The most steps in cultivation and postharvest processing are manual and the aim of this work is to emphasize which variety sustains the processing steps to produce high yield quality rice for strengthening the economic conditions of the people.

  16. Engineering the Mechanical Properties of Polymer Networks with Precise Doping of Primary Defects.

    Science.gov (United States)

    Chan, Doreen; Ding, Yichuan; Dauskardt, Reinhold H; Appel, Eric A

    2017-12-06

    Polymer networks are extensively utilized across numerous applications ranging from commodity superabsorbent polymers and coatings to high-performance microelectronics and biomaterials. For many applications, desirable properties are known; however, achieving them has been challenging. Additionally, the accurate prediction of elastic modulus has been a long-standing difficulty owing to the presence of loops. By tuning the prepolymer formulation through precise doping of monomers, specific primary network defects can be programmed into an elastomeric scaffold, without alteration of their resulting chemistry. The addition of these monomers that respond mechanically as primary defects is used both to understand their impact on the resulting mechanical properties of the materials and as a method to engineer the mechanical properties. Indeed, these materials exhibit identical bulk and surface chemistry, yet vastly different mechanical properties. Further, we have adapted the real elastic network theory (RENT) to the case of primary defects in the absence of loops, thus providing new insights into the mechanism for material strength and failure in polymer networks arising from primary network defects, and to accurately predict the elastic modulus of the polymer system. The versatility of the approach we describe and the fundamental knowledge gained from this study can lead to new advancements in the development of novel materials with precisely defined and predictable chemical, physical, and mechanical properties.

  17. Homeostatic properties of Lactobacillus jensenii engineered as a live vaginal anti-HIV microbicide.

    Science.gov (United States)

    Yamamoto, Hidemi S; Xu, Qiang; Fichorova, Raina N

    2013-01-08

    Vaginal probiotics are investigated as a binary strategy for prevention of bacterial vaginosis and HIV. We applied an innovative experimental model using primary and immortalized human cervical and vaginal epithelial cells to assess the functional properties of Lactobacillus jensenii, a predominant constituent of the healthy vaginal microbiome, engineered to express the HIV-1 entry inhibitor modified cyanovirin-N (mCV-N). In this model bacteria colonize the epithelial cells over a period of 24-72 h. Staurosporine and the Toll-like receptor 2/6 ligand macrophage-activating lipopeptide-2 (MALP-2) serve as positive controls for apoptosis and proinflammatory activation, respectively. In 24-hour intervals, the colonized epithelium is assessed microscopically, supernatants are collected for measurement of soluble immunoinflammatory mediators and production of CV-N, and cells are lysed for assessment of: 1) apoptosis by cleaved versus total caspase-3 assay; 2) NF-κB activation by a luciferase reporter assay; or 3) epithelia-associated colony forming units (CFU) in Brucella agar. Wild type (WT) L. jensenii 1153 consistently colonized cervical and vaginal cells in the absence of epithelial damage and apoptosis. The bioengineered derivatives expressing mCV-N or control plasmids showed the same stable colonization pattern, which was reproducible between technologists and bacterial batches (CFU coefficient of variation <10% within and between experiments and epithelial cell types). MALP-2 activated NF-κB and caused fold-increased levels of proinflammatory mediators with clinically established significance in the cervicovaginal environment (IL-1α, IL-1β, IL-6, TNF-α, IL-8, RANTES, MIP-3α, and ICAM-1), measured by a multiplex electrochemiluminescence assay. At the same time levels of protective anti-inflammatory mediators interleukin 1 receptor antagonist (IL-1RA) and secretory leukocyte protease inhibitor (SLPI), both measured by ELISA, remained constant (IL-1RA) or

  18. Cloning Nacre's 3D Interlocking Skeleton in Engineering Composites to Achieve Exceptional Mechanical Properties.

    Science.gov (United States)

    Zhao, Hewei; Yue, Yonghai; Guo, Lin; Wu, Juntao; Zhang, Youwei; Li, Xiaodong; Mao, Shengcheng; Han, Xiaodong

    2016-07-01

    Ceramic/polymer composite equipped with 3D interlocking skeleton (3D IL) is developed through a simple freeze-casting method, exhibiting exceptionally light weight, high strength, toughness, and shock resistance. Long-range crack energy dissipation enabled by 3D interlocking structure is considered as the primary reinforcing mechanism for such superior properties. The smart composite design strategy should hold a place in developing future structural engineering materials. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Exploration on the reform of the science and engineering experiment teaching based on the combination with teaching and scientific research

    Science.gov (United States)

    Song, Peng

    2017-08-01

    The existing problems of the experiment education in colleges and universities are analyzed. Take the science and engineering specialty as example, the idea of the combination with teaching and scientific research is discussed. The key problems are how the scientific research and scientific research achievements are used effectively in the experiment education, how to effectively use scientific research laboratories and scientific researchers. Then, a specialty experiment education system is established which is good for the teaching in accordance of all students' aptitude. The research in this paper can give the construction of the experiment teaching methods and the experiment system reform for the science and engineering specialties in colleges and universities.

  20. Integrating experiences from operations into engineering design: modelling knowledge transfer in the offshore oil industry

    DEFF Research Database (Denmark)

    Souza da Conceição, Carolina; Broberg, Ole; Paravizo, Esdras

    2017-01-01

    of knowledge registered in the systems without standards to categorise and store this knowledge, to being difficult to access and retrieve the knowledge in the systems. Discussion: Transferring knowledge and experiences from users brings human factors into play and modelling the knowledge transfer process...... and workwise distance between operations and engineering design teams, integrating human factors and transferring knowledge are key aspects when designing for better performance systems. Research Objective: Based on an in-depth empirical investigation in an offshore oil company, this study aims to provide......Summative Statement: Integrating human factors and users’ experiences in design projects is a well-known challenge. This study focus on the specific challenges for transferring these experiences and how using a knowledge transfer model can help this integration on the design of high-risk productive...

  1. Safety research experiment facilities, Idaho National Engineering Laboratory, Idaho. Final environmental impact statement

    International Nuclear Information System (INIS)

    Liverman, J.L.

    1977-09-01

    This environmental statement was prepared for the Safety Research Experiment Facilities (SAREF) Project. The purpose of the proposed project is to modify some existing facilities and provide a new test facility at the Idaho National Engineering Laboratory (INEL) for conducting fast breeder reactor (FBR) safety experiments. The SAREF Project proposal has been developed after an extensive study which identified the FBR safety research needs requiring in-reactor experiments and which evaluated the capability of various existing and new facilities to meet these needs. The proposed facilities provide for the in-reactor testing of large bundles of prototypical FBR fuel elements under a wide variety of conditions, ranging from those abnormal operating conditions which might be expected to occur during the life of an FBR power plant to the extremely low probability, hypothetical accidents used in the evaluation of some design options and in the assessment of the long-term potential risk associated with wide-acale deployment of the FBR

  2. Electro-Mechanical Response and Engineering Properties of Piezocomposite with Imperfect Interface

    Directory of Open Access Journals (Sweden)

    Tippayaphalapholgul Rattanan

    2016-01-01

    Full Text Available Composites of piezoelectric materials are widely use in practical applications such as nondestructive testing devices, smart adaptive structures and medical devices. A thorough understanding of coupled electro-elastic response and properties of piezocomposite are crucial for the development and design of piezoelectric composite materials used in advanced applications. The micromechanics analysis is employed in this paper to determine the response and engineering properties of the piezocomposite. A mechanical imperfect interface bonding between piezoelectric inclusion and polymer matrix is taken into consideration in the analysis. The micromechanics analysis is based on the Boundary Element Method (BEM together with the periodic micro-field micromechanics theory. A selected set of numerical results is presented to investigate the influence of volume ratio and interface bonding condition on effective piezocomposite material coefficients and portray basic features of coupled electroelastic response within the domain of piezocomposite unit cell.

  3. The Comparison of Engineering Properties Between Single and Double Layer Porous Asphalt made of Packing Gradation

    Directory of Open Access Journals (Sweden)

    Hardiman M. Y

    2008-01-01

    Full Text Available is paper presents the comparison of engineering properties between single and double layer porous asphalt (SLPA and DLPA made of packing gradation. Three nominal maximum aggregate sizes (NMAS were tested each made up of 10, 14, and 20 mm for SLPA. While for the DLPA with 30, 20, and 15 mm top layer are made of 10 and 14 mm NMAS, with a base layer of 20 mm NMAS. Total thickness of all mixes is 70 mm. Binders used are 60/70 penetration base bitumen and polymer binder styrene-butadiene-styrene (SBS. The result shows that the properties of SLPA mix namely permeability and resistance to abrasion loss decreases when the NMAS in SLPA decreases. The abrasion loss of DLPA mixes increases when the porous asphalt top layer thickness decreases, while drainage time value decreases. However, SLPA with 20 mm NMAS exhibits higher abrasion loss compared to all DLPA mixes.

  4. Mechanical and fracture properties at impact loading of selected steels for nuclear power engineering

    International Nuclear Information System (INIS)

    Buchar, J.; Bilek, Z.

    1988-01-01

    The possibilities are briefly characterized of experimental research of mechanical and fracture properties of steels used in nuclear power engineering. Attention is paid to plastic deformation and the assessment of fracture formation during impact loading. The results are reported for steels 15Kh2MFA and 10GN2MFA. For steel 15Kh2MFA the effect was also studied of neutron radiation at different temperatures. From the theory developed for non-irradiated material 10GN2MFA, a prediction is made within the original model of the fracture stress value for steel 15Kh2MFA in both non-irradiated and irradiated states. The conclusion is arrived at that the existing methods of assessing steel properties at impact load allow obtaining knowledge of all significant effects during actual stress, this using only small specimens of the materials. (Z.M.). 4 figs., 8 refs

  5. Grain Boundary Engineering the Mechanical Properties of Allvac 718Plus(Trademark) Superalloy

    Science.gov (United States)

    Gabb, Timothy P.; Telesman, Jack; Garg, Anita; Lin, Peter; Provenzano, virgil; Heard, Robert; Miller, Herbert M.

    2010-01-01

    Grain Boundary Engineering can enhance the population of structurally-ordered "low S" Coincidence Site Lattice (CSL) grain boundaries in the microstructure. In some alloys, these "special" grain boundaries have been reported to improve overall resistance to corrosion, oxidation, and creep resistance. Such improvements could be quite beneficial for superalloys, especially in conditions which encourage damage and cracking at grain boundaries. Therefore, the effects of GBE processing on high-temperature mechanical properties of the cast and wrought superalloy Allvac 718Plus (Allvac ATI) were screened. Bar sections were subjected to varied GBE processing, and then consistently heat treated, machined, and tested at 650 C. Creep, tensile stress relaxation, and dwell fatigue crack growth tests were performed. The influences of GBE processing on microstructure, mechanical properties, and associated failure modes are discussed.

  6. Structural and electronic properties of in-plane phase engineered WSe2: A DFT study

    Science.gov (United States)

    Bhart, Ankush; Kapoor, Pooja; Sharma, Munish; Sharma, Raman; Ahluwalia, P. K.

    2018-04-01

    We present first principal investigations on structural and electronic properties of in-plane phase engineered WSe2 with armchair type interface. The 2H and 1T phases of WSe2, joined along x-direction is a natural metal-semiconductor heterostructure and therefore shows potential for applications in 2D electronics and opto-electronics. The electronic properties transit towards metallic 1T region. No inflections across interface shows negligible mismatch strain which is unlike what has been reported for MoS2. Charge density analysis shows charge accumulation on 1T domain. This can lead to reduction of Schottky barrier heights at the metal-semiconductor junction. STM analysis confirms transition of 1T phase towards distorted 1T' structure. The present results provide essential insights for nano-devices using 2D hybrid materials.

  7. Comparison of lubricant properties of castor oil and commercial engine oil

    Directory of Open Access Journals (Sweden)

    Binfa Bongfa

    2015-06-01

    Full Text Available The tribological performance of crude Nigeria-based castor oil has been investigated and compared with that of a foreign, 20W-50 high quality crankcase oil, to see its suitability as base oil for lubricating oils in indigenous vehicle and power plants engines. The experiment was conducted using a four ball tester. The results showed that unrefined castor oil has superior friction reduction and load bearing capability in an unformulated form than the commercial oil; can compete favourably with the commercial oil in wear protection when formulated with suitable antiwear agent, hence can be a good alternative base stock for crankcase oils suitable for Nigeria serviced vehicles, and plants engines from tribological, environmental, and non-food competitive points of view.

  8. Nuclear engineering 24/7 via distance learning: Course development and management experiences

    International Nuclear Information System (INIS)

    Maldonado, G. I.; Christenson, J.; Spitz, H.; Rutz, E.; Todd, A.

    2006-01-01

    This article summarizes a few lessons learned in our early experiences in developing, delivering and implementing a series of distance learning classes for full-time undergraduate students enrolled in the combined-degree BS Mechanical + MS Nuclear Engineering 5-year and co-op based 'MNE- ACCEND' program at the Univ. of Cincinnati. This program is in its third year since inception and currently hosts approximately 35 undergraduate students enrolled in the graduating classes of 2008, 2009, and 2010, which is when these students are expected to complete their BS Mechanical and MS Nuclear Engineering degrees. In addition, 20+ newly confirmed students are expected to enter this program in the fall quarter of 2006 to become our Class of 2011. Therefore, the successful 'follow through' of the DL component of this program continues to be increasingly crucial as this student pipeline reaches a targeted steady-state of about 10 to 15 graduates per class. (authors)

  9. Experience of Use of Knowledge Relative Assessment System for Training in Area of Civil Engineering

    Directory of Open Access Journals (Sweden)

    Romanova Elena

    2017-01-01

    Full Text Available Nowadays E-Learning is becoming more and more relevant in training civil engineers. Electronic resources are used for classroom activities and for independent work. It allows allocating extra time for development of practical skills. Experience of remote knowledge control application in the educational process of Moscow State University of Civil Engineering is presented in the article. The control system is called Knowledge Relative Assessment System using Bekker's method. The following steps of system using are described in detail in the article: loading test material, action of users, protection from wrong acts and calculation of rating. The main merits and demerits from the point of view of teachers and students are listed.

  10. Popham Beach, Maine: An example of engineering activity that saved beach property without harming the beach

    Science.gov (United States)

    Kelley, Joseph T.

    2013-10-01

    Beach and property erosion on coasts is a widespread and chronic problem. Historical approaches to this issue, including seawalls and sand replenishment, are often inappropriate or too expensive. In Maine, seawalls were banned in 1983 and replenishment is too costly to employ. Replacement of storm-damaged buildings is also not allowed, and a precedent case on Popham Beach, Maine required that the owner remove an unpermitted building from a site where an earlier structure was damaged. When the most popular park in Maine, Popham Beach State Park, experienced inlet associated erosion that threatened park infrastructure (a bathhouse), temporary measures were all that the law allowed. Because it was clear that the inlet channel causing the erosion would eventually change course, the state opted to erect a temporary seawall with fallen trees at the site. This may or may not have slowed the erosion temporarily, but reassured the public that "something was being done". Once a storm cut a new tidal inlet channel and closed off the old one, tidal water still entered the former channel and continued to threaten the bathhouse. To ultimately save the property, beach scraping was employed. Sand was scraped from the lower beach to construct a sand berm that deflected the tidal current away from the endangered property. This action created enough time for natural processes to drive the remains of the former spit onto the beach and widen it significantly. Whereas many examples of engineering practices exist that endanger instead of saving beaches, this example is one of an appropriate engineering effort to rescue unwisely located beach-front property.

  11. Dielectric Characteristics of Microstructural Changes and Property Evolution in Engineered Materials

    Science.gov (United States)

    Clifford, Jallisa Janet

    Heterogeneous materials are increasingly used in a wide range of applications such as aerospace, civil infrastructure, fuel cells and many others. The ability to take properties from two or more materials to create a material with properties engineered to needs is always very attractive. Hence heterogeneous materials are evolving into more complex formulations in multiple disciplines. Design of microstructure at multiple scales control the global functional properties of these materials and their structures. However, local microstructural changes do not directly cause a proportional change to the global properties (such as strength and stiffness). Instead, local changes follow an evolution process including significant interactions. Therefore, in order to understand property evolution of engineered materials, microstructural changes need to be effectively captured. Characterizing these changes and representing them by material variables will enable us to further improve our material level understanding. In this work, we will demonstrate how microstructural features of heterogeneous materials can be described quantitatively using broadband dielectric spectroscopy (BbDS). The frequency dependent dielectric properties can capture the change in material microstructure and represent these changes in terms of material variables, such as complex permittivity. These changes in terms of material properties can then be linked to a number of different conditions, such as increasing damage due to impact or fatigue. Two different broadband dielectric spectroscopy scanning modes are presented: bulk measurements and continuous scanning to measure dielectric property change as a function of position across the specimen. In this study, we will focus on ceramic materials and fiber reinforced polymer matrix composites as test bed material systems. In the first part of the thesis, we will present how different micro-structural design of porous ceramic materials can be captured

  12. The path from geoscience to road engineering: experience in Russia and Norway

    Science.gov (United States)

    Kuznetsova, Elena

    2017-04-01

    In the presentation I would like to talk about my personal path from taking the education in geoscience in Russia to getting job as a researcher in road engineering in Norway. I completed my master and PhD at one of the best universities of Russia before getting job in Norway, first at the research institute and the university after. What I noticed was the main different is the role of woman in the research and management positions. I feel that I have more rights and more opportunities for my career in Norway than as it was back in Russia. Road engineering does not sound as very "feminine" specialization, however I have many female colleagues who are doing great job and enjoying their work. I made a lot of observations of my female and male colleagues when it comes to do the laboratory and field work, and to have leadership and management positions. Time to time I am in contact with some former bosses or colleagues from my university in Russia and I see the huge difference with how the communication goes with them and with my colleagues here, in Norway. Few words about myself. I am 31 and I am working as a researcher at the Norwegian university of science and technology. I have 5 years of working experience after obtaining my PhD. My primary background is engineering geology and geocryology. Last 4 years I am working in the field of road construction engineering and one of my main responsibilities is managing the large research project financed by the Norwegian Research Council. During my working life I found a lot of advantages to be a woman in a men world of engineering.

  13. Replication of engine block cylinder bridge microstructure and mechanical properties with lab scale 319 Al alloy billet castings

    International Nuclear Information System (INIS)

    Lombardi, A.; D'Elia, F.; Ravindran, C.; MacKay, R.

    2014-01-01

    In recent years, aluminum alloy gasoline engine blocks have in large part successfully replaced nodular cast iron engine blocks, resulting in improved vehicle fuel efficiency. However, because of the inadequate wear resistance properties of hypoeutectic Al–Si alloys, gray iron cylinder liners are required. These liners cause the development of large tensile residual stress along the cylinder bores and necessitate the maximization of mechanical properties in this region to prevent premature engine failure. The aim of this study was to replicate the engine cylinder bridge microstructure and mechanical properties following TSR treatment (which removes the sand binder to enable easy casting retrieval) using lab scale billet castings of the same alloy composition with varying cooling rates. Comparisons in microstructure between the engine block and the billet castings were carried out using optical and scanning electron microscopy, while mechanical properties were assessed using tensile testing. The results suggest that the microstructure at the top and middle of the engine block cylinder bridge was successfully replicated by the billet castings. However, the microstructure at the bottom of the cylinder was not completely replicated due to variations in secondary phase morphology and distribution. The successful replication of engine block microstructure will enable the future optimization of heat treatment parameters. - Highlights: • A method to replicate engine block microstructure was developed. • Billet castings will allow cost effective optimization of heat treatment process. • The replication of microstructure in the cylinder region was mostly successful. • Porosity was more clustered in the billet castings compared to the engine block. • Mechanical properties were lower in billet castings due to porosity and inclusions

  14. Replication of engine block cylinder bridge microstructure and mechanical properties with lab scale 319 Al alloy billet castings

    Energy Technology Data Exchange (ETDEWEB)

    Lombardi, A., E-mail: a2lombar@ryerson.ca [Centre for Near-net-shape Processing of Materials, Ryerson University, 101 Gerrard Street East, Toronto, Ontario M5B2K3 (Canada); D' Elia, F.; Ravindran, C. [Centre for Near-net-shape Processing of Materials, Ryerson University, 101 Gerrard Street East, Toronto, Ontario M5B2K3 (Canada); MacKay, R. [Nemak of Canada Corporation, 4600 G.N. Booth Drive, Windsor, Ontario N9C4G8 (Canada)

    2014-01-15

    In recent years, aluminum alloy gasoline engine blocks have in large part successfully replaced nodular cast iron engine blocks, resulting in improved vehicle fuel efficiency. However, because of the inadequate wear resistance properties of hypoeutectic Al–Si alloys, gray iron cylinder liners are required. These liners cause the development of large tensile residual stress along the cylinder bores and necessitate the maximization of mechanical properties in this region to prevent premature engine failure. The aim of this study was to replicate the engine cylinder bridge microstructure and mechanical properties following TSR treatment (which removes the sand binder to enable easy casting retrieval) using lab scale billet castings of the same alloy composition with varying cooling rates. Comparisons in microstructure between the engine block and the billet castings were carried out using optical and scanning electron microscopy, while mechanical properties were assessed using tensile testing. The results suggest that the microstructure at the top and middle of the engine block cylinder bridge was successfully replicated by the billet castings. However, the microstructure at the bottom of the cylinder was not completely replicated due to variations in secondary phase morphology and distribution. The successful replication of engine block microstructure will enable the future optimization of heat treatment parameters. - Highlights: • A method to replicate engine block microstructure was developed. • Billet castings will allow cost effective optimization of heat treatment process. • The replication of microstructure in the cylinder region was mostly successful. • Porosity was more clustered in the billet castings compared to the engine block. • Mechanical properties were lower in billet castings due to porosity and inclusions.

  15. Characterizing Design Cognition of High School Students: Initial Analyses Comparing Those with and without Pre-Engineering Experiences

    Science.gov (United States)

    Wells, John; Lammi, Matthew; Gero, John; Grubbs, Michael E.; Paretti, Marie; Williams, Christopher

    2016-01-01

    Reported in this article are initial results from of a longitudinal study to characterize the design cognition and cognitive design styles of high school students with and without pre-engineering course experience over a 2-year period, and to compare them with undergraduate engineering students. The research followed a verbal protocol analysis…

  16. Differences in Chemical Engineering Student-Faculty Interactions by Student Age and Experience at a Large, Public, Research University

    Science.gov (United States)

    Ciston, Shannon; Sehgal, Sanya; Mikel, Tressa; Carnasciali, Maria-Isabel

    2018-01-01

    Adult undergraduate students aged 25+ in engineering disciplines are an important demographic bringing a wealth of life experience to the classroom. This study uses qualitative data drawn from semi-structured interviews with two groups of undergraduate chemical engineering students at a large, public research university: adult students with…

  17. A Guide for Using Mechanical Stimulation to Enhance Tissue-Engineered Articular Cartilage Properties.

    Science.gov (United States)

    Salinas, Evelia Y; Hu, Jerry C; Athanasiou, Kyriacos

    2018-04-26

    The use of tissue-engineered articular cartilage (TEAC) constructs has the potential to become a powerful treatment option for cartilage lesions resulting from trauma or early stages of pathology. Although fundamental tissue-engineering strategies based on the use of scaffolds, cells, and signals have been developed, techniques that lead to biomimetic AC constructs that can be translated to in vivo use are yet to be fully confirmed. Mechanical stimulation during tissue culture can be an effective strategy to enhance the mechanical, structural, and cellular properties of tissue-engineered constructs toward mimicking those of native AC. This review focuses on the use of mechanical stimulation to attain and enhance the properties of AC constructs needed to translate these implants to the clinic. In vivo, mechanical loading at maximal and supramaximal physiological levels has been shown to be detrimental to AC through the development of degenerative changes. In contrast, multiple studies have revealed that during culture, mechanical stimulation within narrow ranges of magnitude and duration can produce anisotropic, mechanically robust AC constructs with high cellular viability. Significant progress has been made in evaluating a variety of mechanical stimulation techniques on TEAC, either alone or in combination with other stimuli. These advancements include determining and optimizing efficacious loading parameters (e.g., duration and frequency) to yield improvements in construct design criteria, such as collagen II content, compressive stiffness, cell viability, and fiber organization. With the advancement of mechanical stimulation as a potent strategy in AC tissue engineering, a compendium detailing the results achievable by various stimulus regimens would be of great use for researchers in academia and industry. The objective is to list the qualitative and quantitative effects that can be attained when direct compression, hydrostatic pressure, shear, and tensile

  18. The influence of propylene glycol ethers on base diesel properties and emissions from a diesel engine

    International Nuclear Information System (INIS)

    Gómez-Cuenca, F.; Gómez-Marín, M.; Folgueras-Díaz, M.B.

    2013-01-01

    Highlights: • Effect of propylene glycol ethers on diesel fuel properties. • Effect of these compounds on diesel engine performance and emissions. • Blends with ⩽4 wt.% of oxygen do not change substantially diesel fuel quality. • Blends with ⩽2.5 wt.% of oxygen reduce CO, HC and NOx emissions, but not smoke. • These compounds are helpful to reach a cleaner combustion in a diesel engine. - Abstract: The oxygenated additives propylene glycol methyl ether (PGME), propylene glycol ethyl ether (PGEE), dipropylene glycol methyl ether (DPGME) were studied to determine their influence on both the base diesel fuel properties and the exhaust emissions from a diesel engine (CO, NOx, unburnt hydrocarbons and smoke). For diesel blends with low oxygen content (⩽4.0 wt.%), the addition of these compounds to base diesel fuel decreases aromatic content, kinematic viscosity, cold filter plugging point and Conradson carbon residue. Also, each compound modifies the distillation curve at temperatures below the corresponding oxygenated compound boiling point, the distillate percentage being increased. The blend cetane number depends on the type of propylene glycol ether added, its molecular weight, and the oxygen content of the fuel. The addition of PGME decreased slightly diesel fuel cetane number, while PGEE and DPGME increased it. Base diesel fuel-propylene glycol ether blends with 1.0 and 2.5 wt.% oxygen contents were used in order to determine the performance of the diesel engine and its emissions at both full and medium loads and different engine speeds (1000, 2500 and 4000 rpm). In general, at full load and in comparison with base diesel fuel, the blends show a slight reduction of oxygen-free specific fuel consumption. CO emissions are reduced appreciably for 2.5 wt.% of oxygen blends, mainly for PGEE and DPGME. NOx emissions are reduced slightly, but not the smoke. Unburnt hydrocarbon emissions decrease at 1000 and 2500 rpm, but not at 4000 rpm. At medium load

  19. Developing an Innovative and Creative Hands-on Lean Six Sigma Manufacturing Experiments for Engineering Education

    Directory of Open Access Journals (Sweden)

    I. Badawi

    2016-12-01

    Full Text Available The goal of this study was to develop an innovative and creative hands-on project based on Lean Six Sigma experiments for engineering education at the College of Engineering at the University of Hail. The exercises were designed using junction box assembly to meet the following learning outcomes: 1-to provide students with solid experience on waste elimination and variation reduction and 2-to engage students in exercises related to assembly line mass production and motion study. To achieve these objectives, students were introduced to the principles of Lean manufacturing and Six Sigma through various pedagogical activities such as classroom instruction, laboratory experiments, hands-on exercises, and interactive group work. In addition, Minitab 17 statistical package and Quality Companion 3 software were used to facilitate The Lean Six Sigma exercises. The software application and hands-on manufacturing assembly were found to be extremely valuable in giving students the chance to identify which variables to control in order to minimize variation and eliminate waste. This research was funded by a grant from the Deanship of Academic Research at University of Hail for project number E-26-IC, and under the umbrella of Ministry of Education within the framework of the National Initiative on Creativity and Innovation in Saudi Universities at University of Hail.

  20. Mathematical Modeling of Uniaxial Mechanical Properties of Collagen Gel Scaffolds for Vascular Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Ramiro M. Irastorza

    2015-01-01

    Full Text Available Small diameter tissue-engineered arteries improve their mechanical and functional properties when they are mechanically stimulated. Applying a suitable stress and/or strain with or without a cycle to the scaffolds and cells during the culturing process resides in our ability to generate a suitable mechanical model. Collagen gel is one of the most used scaffolds in vascular tissue engineering, mainly because it is the principal constituent of the extracellular matrix for vascular cells in human. The mechanical modeling of such a material is not a trivial task, mainly for its viscoelastic nature. Computational and experimental methods for developing a suitable model for collagen gels are of primary importance for the field. In this research, we focused on mechanical properties of collagen gels under unconfined compression. First, mechanical viscoelastic models are discussed and framed in the control system theory. Second, models are fitted using system identification. Several models are evaluated and two nonlinear models are proposed: Mooney-Rivlin inspired and Hammerstein models. The results suggest that Mooney-Rivlin and Hammerstein models succeed in describing the mechanical behavior of collagen gels for cyclic tests on scaffolds (with best fitting parameters 58.3% and 75.8%, resp.. When Akaike criterion is used, the best is the Mooney-Rivlin inspired model.

  1. Effect of by-product steel slag on the engineering properties of clay soils

    Directory of Open Access Journals (Sweden)

    Faisal I. Shalabi

    2017-10-01

    Full Text Available Clay soils, mainly if they contain swelling minerals such as smectite or illite, may cause severe damage to structures, especially when these soils are subjected to wetting and drying conditions. High expansion and reduction in shear strength and foundation bearing capacity will take place due to the increase in water content of these soils. The engineering properties of these kinds of soils can be improved by using additives and chemical stabilizers. In this work, by-product steel slag was used to improve the engineering properties of clay soils. Lab and field experimental programs were developed to investigate the effect of adding different percentages of steel slag on plasticity, swelling, compressibility, shear strength, compaction, and California bearing ratio (CBR of the treated materials. The results of tests on the clay soil showed that as steel slag content increased, the soil dry density, plasticity, swelling potential, and cohesion intercept decreased and the angle of internal friction increased. For the CBR, the results of the tests showed an increase in the CBR value with the increase in slag content.

  2. Mathematical modeling of uniaxial mechanical properties of collagen gel scaffolds for vascular tissue engineering.

    Science.gov (United States)

    Irastorza, Ramiro M; Drouin, Bernard; Blangino, Eugenia; Mantovani, Diego

    2015-01-01

    Small diameter tissue-engineered arteries improve their mechanical and functional properties when they are mechanically stimulated. Applying a suitable stress and/or strain with or without a cycle to the scaffolds and cells during the culturing process resides in our ability to generate a suitable mechanical model. Collagen gel is one of the most used scaffolds in vascular tissue engineering, mainly because it is the principal constituent of the extracellular matrix for vascular cells in human. The mechanical modeling of such a material is not a trivial task, mainly for its viscoelastic nature. Computational and experimental methods for developing a suitable model for collagen gels are of primary importance for the field. In this research, we focused on mechanical properties of collagen gels under unconfined compression. First, mechanical viscoelastic models are discussed and framed in the control system theory. Second, models are fitted using system identification. Several models are evaluated and two nonlinear models are proposed: Mooney-Rivlin inspired and Hammerstein models. The results suggest that Mooney-Rivlin and Hammerstein models succeed in describing the mechanical behavior of collagen gels for cyclic tests on scaffolds (with best fitting parameters 58.3% and 75.8%, resp.). When Akaike criterion is used, the best is the Mooney-Rivlin inspired model.

  3. Macroscopic Properties of Hollow Cone Spray Using an Outwardly Opening Piezoelectric Injector in GCI Engine

    KAUST Repository

    Cheng, Penghui

    2016-07-01

    Fuel mixture formation and spray characteristics are crucial for the advancement of Gasoline Compression Ignition (GCI) engine. For investigations of spray characteristics, a high-pressure high-temperature spray chamber with constant volume has been designed, tested and commissioned at CCRC, KAUST. Back light illumination technique has been applied to investigate the macroscopic spray properties of an outwardly opening piezoelec- tric injector. Three parameters including injection pressure, ambient pressure, and ambient temperature have been involved. A total of 18 combinations of experimental conditions were tested under non-reactive conditions. Through qualitative analysis of spray morphology under different operating conditions, an apparent distinction of spray morphology has been noticed. Spray morphology and propagation have shown strong dependencies on ambient pressure and ambient tempera- ture while injection pressure has a negligible effect on spray shape. Increasingly compact and bushier spray patterns were observed in the cases of high ambient pressure due to in- creasing aerodynamic drag force on spray boundary. It should also be noted that ambient temperature plays a fairly important role in fuel evaporation rate. At 200 °C, oscillating and considerably short spray shape was produced. Also, circumferential ring-like vortices and distinctive string-like structures have been identified for the fuel spray exiting this hollow cone injector. It has been observed that high ambient pressure conditions (Pamb = 4 bar and 10.5 bar) are favorable to the vortices generation, which has also been reported in previous literature. The quantitative description of macroscopic spray properties reveals that ambient pres- sure and ambient temperature are found to be the most influential parameters on liquid penetration length. The rise of ambient pressure results in considerably shorter liquid pen- etration length. Ambient temperature also appears to be a very effective

  4. Long-term stability and properties of zirconia ceramics for heavy duty diesel engine components

    Science.gov (United States)

    Larsen, D. C.; Adams, J. W.

    1985-01-01

    Physical, mechanical, and thermal properties of commercially available transformation-toughened zirconia are measured. Behavior is related to the material microstructure and phase assemblage. The stability of the materials is assessed after long-term exposure appropriate for diesel engine application. Properties measured included flexure strength, elastic modulus, fracture toughness, creep, thermal shock, thermal expansion, internal friction, and thermal diffusivity. Stability is assessed by measuring the residual property after 1000 hr/1000C static exposure. Additionally static fatigue and thermal fatigue testing is performed. Both yttria-stabilized and magnesia-stabilized materials are compared and contrasted. The major limitations of these materials are short term loss of properties with increasing temperature as the metastable tetragonal phase becomes more stable. Fine grain yttria-stabilized material (TZP) is higher strength and has a more stable microstructure with respect to overaging phenomena. The long-term limitation of Y-TZP is excessive creep deformation. Magnesia-stabilized PSZ has relatively poor stability at elevated temperature. Overaging, decomposition, and/or destabilization effects are observed. The major limitation of Mg-PSZ is controlling unwanted phase changes at elevated temperature.

  5. Polymer structure-property requirements for stereolithographic 3D printing of soft tissue engineering scaffolds.

    Science.gov (United States)

    Mondschein, Ryan J; Kanitkar, Akanksha; Williams, Christopher B; Verbridge, Scott S; Long, Timothy E

    2017-09-01

    This review highlights the synthesis, properties, and advanced applications of synthetic and natural polymers 3D printed using stereolithography for soft tissue engineering applications. Soft tissue scaffolds are of great interest due to the number of musculoskeletal, cardiovascular, and connective tissue injuries and replacements humans face each year. Accurately replacing or repairing these tissues is challenging due to the variation in size, shape, and strength of different types of soft tissue. With advancing processing techniques such as stereolithography, control of scaffold resolution down to the μm scale is achievable along with the ability to customize each fabricated scaffold to match the targeted replacement tissue. Matching the advanced manufacturing technique to polymer properties as well as maintaining the proper chemical, biological, and mechanical properties for tissue replacement is extremely challenging. This review discusses the design of polymers with tailored structure, architecture, and functionality for stereolithography, while maintaining chemical, biological, and mechanical properties to mimic a broad range of soft tissue types. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Excess Properties of Aqueous Mixtures of Methanol: Simulation Versus Experiment

    Czech Academy of Sciences Publication Activity Database

    González-Salgado, D.; Nezbeda, Ivo

    2006-01-01

    Roč. 240, č. 2 (2006), s. 161-166 ISSN 0378-3812 R&D Projects: GA AV ČR(CZ) IAA4072303 Grant - others:BEMUSAC(XE) G1MA/CT/2002/04019 Institutional research plan: CEZ:AV0Z40720504 Keywords : aqueous mixtures * excess properties * partial molar properties Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.680, year: 2006

  7. Engineering Geological Properties of Oil-Contaminated Granitic and Meta sedimentary Soils

    International Nuclear Information System (INIS)

    Zulfahmi Ali Rahman; Umar Hamzah; Noorulakma Ahmad

    2011-01-01

    Hydrocarbon is a light-non aqueous phase liquid or known as LNAPL. It poses environmental hazard if accidentally spilled out into the soil and water systems as a result of its insoluble nature in water. LNAPL component infiltrates into soil through pore spaces and afloat at the top of groundwater level. Some of this hydrocarbon would trap and clog within the voids, difficult to remove and costly to clean. The occurrence of hydrocarbon in the soil definitely degraded the behaviour of soils in terms of engineering properties. This study aimed to investigate the engineering properties of oil-contaminated soil for two different residual soils originally developed from in-situ weathering of granitic and meta sedimentary rocks. The physical characterisations of the soil were determined including particle size distribution, specific gravity test and x-ray diffraction (XRD). The engineering parameters for the contaminated and uncontaminated soils were Atterberg limits, compaction and soil shear strength (UU tests). The amounts of hydrocarbon added to soil were varied at 0 %, 4 %, 8 %, 12 % and 16 % of dried weight of soil samples. The results from the particle size distribution analysis showed that residual soil from granitic rock comprises of 38 % sand, 33 % silt and 4 % clay while meta sedimentary soil consists of 4 % sand, 43 % silt dan 29 % clay. The mean values of specific gravity for the granitic and meta sedimentary soils were 2.56 and 2.61, respectively. The types of minerals present in granitic soil sample were quartz, kaolinite and gibbsite while meta sedimentary soil consists of quartz and kaolinite. The Atterberg limits value decreased as a result of increasing amount of added hydrocarbon into the soil. A similar behavior was observed with the values of maximum dry density and optimum water content with increasing hydrocarbon content. The overall unconsolidated undrained shear strength, C u showed a decreasing trend with the increase in hydrocarbon content

  8. Effects of ethylene glycol ethers on diesel fuel properties and emissions in a diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Cuenca, F.; Gomez-Marin, M. [Compania Logistica de Hidrocarburos (CLH), Central Laboratory, Mendez Alvaro 44, 28045 Madrid (Spain); Folgueras-Diaz, M.B., E-mail: belenfd@uniovi.es [Department of Energy, University of Oviedo, Independencia 13, 33004 Oviedo (Spain)

    2011-08-15

    Highlights: {yields} Effect of ethylene glycol ethers on diesel fuel properties. {yields} Effect of ethylene glycol ethers on diesel engine specific consumption and emissions. {yields} Blends with {<=}4 wt.% of oxygen do not change substantially diesel fuel quality. {yields} Blends with 1 and 2.5 wt.% of oxygen reduce CO and HC emissions, but not smoke. - Abstract: The effect of ethylene glycol ethers on both the diesel fuel characteristics and the exhaust emissions (CO, NO{sub x}, smoke and hydrocarbons) from a diesel engine was studied. The ethers used were monoethylene glycol ethyl ether (EGEE), monoethylene glycol butyl ether (EGBE), diethylene glycol ethyl ether (DEGEE). The above effect was studied in two forms: first by determining the modification of base diesel fuel properties by using blends with oxygen concentration around 4 wt.%, and second by determining the emission reductions for blends with low oxygen content (1 wt.%) and with 2.5 wt.% of oxygen content. The addition of DEGEE enhances base diesel fuel cetane number, but EGEE and EGBE decrease it. For concentrations of {>=}4 wt.% of oxygen, EGEE and diesel fuel can show immiscibility problems at low temperatures ({<=}0 {sup o}C). Also, every oxygenated compound, according to its boiling point, modifies the distillation curve at low temperatures and the distillate percentage increases. These compounds have a positive effect on diesel fuel lubricity, and slightly decrease its viscosity. Blends with 1 and 2.5 wt.% oxygen concentrations were used in order to determine their influence on emissions at both full and medium loads and different engine speeds. Generally, all compounds help to reduce CO, and hydrocarbon emissions, but not smoke. The best results were obtained for blends with 2.5 wt.% of oxygen. At this concentration, the additive efficiency in decreasing order was EGEE > DEGEE > EGBE for CO emissions and DGEE > EGEE > EGBE for hydrocarbon emissions. For NO{sub x}, both its behaviour and the

  9. Growth factor stimulation improves the structure and properties of scaffold-free engineered auricular cartilage constructs.

    Directory of Open Access Journals (Sweden)

    Renata G Rosa

    Full Text Available The reconstruction of the external ear to correct congenital deformities or repair following trauma remains a significant challenge in reconstructive surgery. Previously, we have developed a novel approach to create scaffold-free, tissue engineering elastic cartilage constructs directly from a small population of donor cells. Although the developed constructs appeared to adopt the structural appearance of native auricular cartilage, the constructs displayed limited expression and poor localization of elastin. In the present study, the effect of growth factor supplementation (insulin, IGF-1, or TGF-β1 was investigated to stimulate elastogenesis as well as to improve overall tissue formation. Using rabbit auricular chondrocytes, bioreactor-cultivated constructs supplemented with either insulin or IGF-1 displayed increased deposition of cartilaginous ECM, improved mechanical properties, and thicknesses comparable to native auricular cartilage after 4 weeks of growth. Similarly, growth factor supplementation resulted in increased expression and improved localization of elastin, primarily restricted within the cartilaginous region of the tissue construct. Additional studies were conducted to determine whether scaffold-free engineered auricular cartilage constructs could be developed in the 3D shape of the external ear. Isolated auricular chondrocytes were grown in rapid-prototyped tissue culture molds with additional insulin or IGF-1 supplementation during bioreactor cultivation. Using this approach, the developed tissue constructs were flexible and had a 3D shape in very good agreement to the culture mold (average error <400 µm. While scaffold-free, engineered auricular cartilage constructs can be created with both the appropriate tissue structure and 3D shape of the external ear, future studies will be aimed assessing potential changes in construct shape and properties after subcutaneous implantation.

  10. Teaching introductory game development with unreal engine: Challenges, strategies, and experiences

    Science.gov (United States)

    Head, Nicholas A.

    From the days of Pong to 100 million dollar projects such as the Grand Theft Auto franchise, video games have evolved significantly over the years. This evolution has also changed the way game development is viewed as a career. Today, video games are one of the most profitable forms of entertainment, and game development courses are appearing at universities around the world. Even with this growth, a degree from a university has yet to be an important factor in finding a job in game development (Owen, 2013). This thesis examines a method of creating and implementing an introductory gaming course and recommends ways to improve the curriculum. The main focus of the course was to introduce game development to the students. Each week, they were given an exercise that covered a different topic. Students also took part in a team project in which they were tasked with creating a complete game. The goal of the team projects was to expand the student's basic knowledge given to them from the exercises. Data was gathered on the students' subjective experiences with the class. This data and the class's overall performance were compared with past iterations of the course. New to the course was the Unreal Engine. Students used the latest version of the engine, Unreal Engine 4, to complete exercises. Not all students chose to use this engine for the team project. Instructor and students experiences with the engine were also recorded. While there were some problems implementing the engine within our lab environment, we were still able to execute the overall lesson plan. Even with the engine issues, the course had overall good performance. CGT 241, Introduction to 3D Animation, was shown to help the students to complete the course while CGT 215, Computer Graphics Programming I, did not provide enough information on game programming. Exercises were found to be helpful but students wanted a better understanding of how these skills can be applied to game development. Team projects

  11. Biphasic Finite Element Modeling Reconciles Mechanical Properties of Tissue-Engineered Cartilage Constructs Across Testing Platforms.

    Science.gov (United States)

    Meloni, Gregory R; Fisher, Matthew B; Stoeckl, Brendan D; Dodge, George R; Mauck, Robert L

    2017-07-01

    Cartilage tissue engineering is emerging as a promising treatment for osteoarthritis, and the field has progressed toward utilizing large animal models for proof of concept and preclinical studies. Mechanical testing of the regenerative tissue is an essential outcome for functional evaluation. However, testing modalities and constitutive frameworks used to evaluate in vitro grown samples differ substantially from those used to evaluate in vivo derived samples. To address this, we developed finite element (FE) models (using FEBio) of unconfined compression and indentation testing, modalities commonly used for such samples. We determined the model sensitivity to tissue radius and subchondral bone modulus, as well as its ability to estimate material parameters using the built-in parameter optimization tool in FEBio. We then sequentially tested agarose gels of 4%, 6%, 8%, and 10% weight/weight using a custom indentation platform, followed by unconfined compression. Similarly, we evaluated the ability of the model to generate material parameters for living constructs by evaluating engineered cartilage. Juvenile bovine mesenchymal stem cells were seeded (2 × 10 7 cells/mL) in 1% weight/volume hyaluronic acid hydrogels and cultured in a chondrogenic medium for 3, 6, and 9 weeks. Samples were planed and tested sequentially in indentation and unconfined compression. The model successfully completed parameter optimization routines for each testing modality for both acellular and cell-based constructs. Traditional outcome measures and the FE-derived outcomes showed significant changes in material properties during the maturation of engineered cartilage tissue, capturing dynamic changes in functional tissue mechanics. These outcomes were significantly correlated with one another, establishing this FE modeling approach as a singular method for the evaluation of functional engineered and native tissue regeneration, both in vitro and in vivo.

  12. Making a search engine for Indocean - A database of abstracts: An experience

    Digital Repository Service at National Institute of Oceanography (India)

    Tapaswi, M.P.; Haravu, L.J.

    stream_size 23701 stream_content_type text/plain stream_name Inf_Manage_Trends_Issues_2003_307.pdf.txt stream_source_info Inf_Manage_Trends_Issues_2003_307.pdf.txt Content-Encoding UTF-8 Content-Type text/plain; charset=UTF-8... Information Mallagement : Trends and Issues (Festschrift ill honour of Prof S. Seetharama) 52 . Making a Search Engine for Indocean - A Database of Abstracts : An Experience Murari P Tapaswi* and L J Haravu** *Documentation Officer. National Information...

  13. Bloch-wave engineered submicron-diameter quantum-dot micropillars for cavity QED experiments

    DEFF Research Database (Denmark)

    Gregersen, Niels; Lermer, Matthias; Reitzenstein, Stephan

    2013-01-01

    The semiconductor micropillar is attractive for cavity QED experiments. For strong coupling, the figure of merit is proportional to Q/√V, and a design combining a high Q and a low mode volume V is thus desired. However, for the standard submicron diameter design, poor mode matching between the ca...... the cavity and the DBR Bloch mode limits the Q. We present a novel adiabatic design where Bloch-wave engineering is employed to improve the mode matching, allowing the demonstration of a record-high vacuum Rabi splitting of 85 μeV and a Q of 13600 for a 850 nm diameter micropillar....

  14. Integration of the clinical engineering specialist at a high complexity children's hospital. Our professional experience at a surgical center

    International Nuclear Information System (INIS)

    Vargas Enriquez, M J; Chazarreta, B; Emilio, D G; Fernandez Sarda, E

    2007-01-01

    This document aims to find relating points between the current and future Clinical Engineer professional in order to discuss about the hospital environment, its characteristics and its realities which lead to our professional development. The main aim is to depict our experience through a retrospective analysis based on the underwriting experience and consequently to arrive at conclusions that will support the inclusion and active interaction of the Clinic Engineer Specialist as part of a Hospital's Surgical Center

  15. Learning Experience and Socio-Cultural Influences on Female Engineering Students' Perspectives on Engineering Courses and Careers

    Science.gov (United States)

    Balakrishnan, Balamuralithara; Low, Foon Siang

    2016-01-01

    As developed and developing countries move towards greater technological development in the 21st century, the need for engineers has increased substantially. Japan is facing the dilemma of insufficient engineers; therefore, the country has to rely on foreign workers. This problem may be resolved if there is a continuous effort to increase the…

  16. A demonstration experiment for studying the properties of saturated vapor

    Science.gov (United States)

    Grebenev, Igor V.; Lebedeva, Olga V.; Polushkina, Svetlana V.

    2017-11-01

    The paper proposes an important demonstration experiment that can be used at secondary schools in physics. The described experiment helps students learn the main concepts of the topic ‘saturated vapor’, namely, evaporation, condensation, dynamic equilibrium, saturation vapor, partial pressure, and the dependence of saturated vapor pressure on temperature.

  17. Internalisation of engineered nanoparticles into mammalian cells in vitro: influence of cell type and particle properties

    International Nuclear Information System (INIS)

    Busch, Wibke; Bastian, Susanne; Trahorsch, Ulrike; Iwe, Maria; Kühnel, Dana; Meißner, Tobias; Springer, Armin; Gelinsky, Michael; Richter, Volkmar; Ikonomidou, Chrysanthy; Potthoff, Annegret; Lehmann, Irina; Schirmer, Kristin

    2011-01-01

    Cellular internalisation of industrial engineered nanoparticles is undesired and a reason for concern. Here we investigated and compared the ability of seven different mammalian cell cultures in vitro to incorporate six kinds of engineered nanoparticles, focussing on the role of cell type and particle properties in particle uptake. Uptake was examined using light and electron microscopy coupled with energy dispersive X-ray spectroscopy (EDX) for particle element identification. Flow cytometry was applied for semi-quantitative analyses of particle uptake and for exploring the influence on uptake by the phagocytosis inhibitor Cytochalasin D (CytoD). All particles studied were found to enter each kind of cultured cells. Yet, particles were never found within cell nuclei. The presence of the respective particles within the cells was confirmed by EDX. Live-cell imaging revealed the time-dependent process of internalisation of technical nanoparticles, which was exemplified by tungsten carbide particle uptake into the human skin cells, HaCaT. Particles were found to co-localise with lysosomal structures within the cells. The incorporated nanoparticles changed the cellular granularity, as measured by flow cytometry, already after 3 h of exposure in a particle specific manner. By correlating particle properties with flow cytometry data, only the primary particle size was found to be a weakly influential property for particle uptake. CytoD, an inhibitor of actin filaments and therewith of phagocytosis, significantly inhibited the internalisation of particle uptake in only two of the seven investigated cell cultures. Our study, therefore, supports the notion that nanoparticles can enter mammalian cells quickly and easily, irrespective of the phagocytic ability of the cells.

  18. Experiences in the application of human factors engineering to human-system interface modernization

    International Nuclear Information System (INIS)

    Trueba Alonso, Pedro; Illobre, Luis Fernandez; Ortega Pascual, Fernando

    2014-01-01

    Almost all the existing Nuclear Power Plants (NPPs) include plans to modernize their existing Instrumentation and Control (I and C) systems and associated Human System Interfaces (HSIs), due to obsolescence problems. Tecnatom, S.A. has been participating in modernization programs in NPPs to help them to plan, specify, design and implement the modernization of control rooms and associated I and C and HSIs. The application of Human Factors Engineering (HFE) in modernization programs is nowadays unavoidable. This is because is becoming a regulatory requirement, and also because it is needed to ensure that any plant modification, involving the modernization of I and C and HSI, is well designed to improve overall plant operations, reliability, and safety. This paper shows some experiences obtained during the application of HFE to the modernization of these HSIs. The experience applying HFE in modernizations and design modifications show a positive effect, improving the associated HSIs, with the acceptability of the final user. (authors)

  19. A Progress Review on Soot Experiments and Modeling in the Engine Combustion Network (ECN)

    KAUST Repository

    Skeen, Scott A.

    2016-04-05

    The 4th Workshop of the Engine Combustion Network (ECN) was held September 5-6, 2015 in Kyoto, Japan. This manuscript presents a summary of the progress in experiments and modeling among ECN contributors leading to a better understanding of soot formation under the ECN “Spray A” configuration and some parametric variants. Relevant published and unpublished work from prior ECN workshops is reviewed. Experiments measuring soot particle size and morphology, soot volume fraction (fv), and transient soot mass have been conducted at various international institutions providing target data for improvements to computational models. Multiple modeling contributions using both the Reynolds Averaged Navier-Stokes (RANS) Equations approach and the Large-Eddy Simulation (LES) approach have been submitted. Among these, various chemical mechanisms, soot models, and turbulence-chemistry interaction (TCI) methodologies have been considered.

  20. Experience within the CERN Civil Engineering Group with Outsourced Design Services

    CERN Document Server

    Watson, T

    1998-01-01

    In April 1996, CERN awarded three contracts for civil engineering design services associated with the LHC project. The three contracts were awarded to three different joint ventures of firms from five member states. The total bid price for these services was in excess of 35 MCHF and the contracts will run for up to seven years. This paper aims to discuss and analyze the experience gained to date in the management of these contracts. In particular, the paper will address the issues of conditions of contract and specification for this form of contract. Current experience with each of the three consultants will be presented with the areas of difficulty highlighted. Conclusions will be made regarding future use of such contracts and in particular the way in which CERN must change in order to work efficiently with external designers.

  1. Experiences in the application of human factors engineering to human-system interface modernization

    International Nuclear Information System (INIS)

    Trueba Alonso, Pedro; Fernandez Illobre, Luis; Ortega Pascual, Fernando

    2015-01-01

    Almost all the existing Nuclear Power Plants (NPPs) include plans to modernize their existing Instrumentation and Control (I and C) systems and associated Human System Interfaces (HSIs), due to obsolescence problems. Tecnatom, S.A. has been participating in modernization programs in NPPs to help them to plan, specify, design and implement the modernization of control rooms and associated I and C and HSIs. The application of Human Factors Engineering (HFE) in modernization programs is nowadays unavoidable. This is because is becoming a regulatory requirement, and also because it is needed to ensure that any plant modification, involving the modernization of I and C and HSI, is well designed to improve overall plant operations, reliability, and safety. This paper shows some experiences obtained during the application of HFE to the modernization of these HSIs. The experience applying HFE in modernizations and design modifications show a positive effect, improving the associated HSIs, with the acceptability of the final user.

  2. A Progress Review on Soot Experiments and Modeling in the Engine Combustion Network (ECN)

    KAUST Repository

    Skeen, Scott A.; Manin, Julien; Pickett, Lyle M.; Cenker, Emre; Bruneaux, Gilles; Kondo, Katsufumi; Aizawa, Tets; Westlye, Fredrik; Dalen, Kristine; Ivarsson, Anders; Xuan, Tiemin; Garcia-Oliver, Jose M; Pei, Yuanjiang; Som, Sibendu; Hu, Wang; Reitz, Rolf D.; Lucchini, Tommaso; D'Errico, Gianluca; Farrace, Daniele; Pandurangi, Sushant S.; Wright, Yuri M.; Chishty, Muhammad Aqib; Bolla, Michele; Hawkes, Evatt

    2016-01-01

    The 4th Workshop of the Engine Combustion Network (ECN) was held September 5-6, 2015 in Kyoto, Japan. This manuscript presents a summary of the progress in experiments and modeling among ECN contributors leading to a better understanding of soot formation under the ECN “Spray A” configuration and some parametric variants. Relevant published and unpublished work from prior ECN workshops is reviewed. Experiments measuring soot particle size and morphology, soot volume fraction (fv), and transient soot mass have been conducted at various international institutions providing target data for improvements to computational models. Multiple modeling contributions using both the Reynolds Averaged Navier-Stokes (RANS) Equations approach and the Large-Eddy Simulation (LES) approach have been submitted. Among these, various chemical mechanisms, soot models, and turbulence-chemistry interaction (TCI) methodologies have been considered.

  3. Experiences in the application of human factors engineering to human-system interface modernization

    Energy Technology Data Exchange (ETDEWEB)

    Trueba Alonso, Pedro; Fernandez Illobre, Luis; Ortega Pascual, Fernando [Tecnatom S.A., San Sebastian de los Reyes (Spain). Simulation and Control Rooms Div.

    2015-07-15

    Almost all the existing Nuclear Power Plants (NPPs) include plans to modernize their existing Instrumentation and Control (I and C) systems and associated Human System Interfaces (HSIs), due to obsolescence problems. Tecnatom, S.A. has been participating in modernization programs in NPPs to help them to plan, specify, design and implement the modernization of control rooms and associated I and C and HSIs. The application of Human Factors Engineering (HFE) in modernization programs is nowadays unavoidable. This is because is becoming a regulatory requirement, and also because it is needed to ensure that any plant modification, involving the modernization of I and C and HSI, is well designed to improve overall plant operations, reliability, and safety. This paper shows some experiences obtained during the application of HFE to the modernization of these HSIs. The experience applying HFE in modernizations and design modifications show a positive effect, improving the associated HSIs, with the acceptability of the final user.

  4. Notion Of Artificial Labs Slow Global Warming And Advancing Engine Studies Perspectives On A Computational Experiment On Dual-Fuel Compression-Ignition Engine Research

    Directory of Open Access Journals (Sweden)

    Tonye K. Jack

    2017-06-01

    Full Text Available To appreciate clean energy applications of the dual-fuel internal combustion engine D-FICE with pilot Diesel fuel to aid public policy formulation in terms of present and future benefits to the modern transportation stationary power and promotion of oil and gas green- drilling the brief to an engine research team was to investigate the feasible advantages of dual-fuel compression-ignition engines guided by the following concerns i Sustainable fuel and engine power delivery ii The requirements for fuel flexibility iii Low exhausts emissions and environmental pollution iv Achieving low specific fuel consumption and economy for maximum power v The comparative advantages over the conventional Diesel engines vi Thermo-economic modeling and analysis for the optimal blend as basis for a benefitcost evaluation Planned in two stages for reduced cost and fast turnaround of results - initial preliminary stage with basic simple models and advanced stage with more detailed complex modeling. The paper describes a simplified MATLAB based computational experiment predictive model for the thermodynamic combustion and engine performance analysis of dual-fuel compression-ignition engine studies operating on the theoretical limited-pressure cycle with several alternative fuel-blends. Environmental implications for extreme temperature moderation are considered by finite-time thermodynamic modeling for maximum power with predictions for pollutants formation and control by reaction rates kinetics analysis of systematic reduced plausible coupled chemistry models through the NCN reaction pathway for the gas-phase reactions classes of interest. Controllable variables for engine-out pollutants emissions reduction and in particular NOx elimination are identified. Verifications and Validations VampV through Performance Comparisons were made using a clinical approach in selection of StrokeBore ratios greater-than and equal-to one amp88051 low-to-high engine speeds and medium

  5. GT-SUPREEM: the Georgia Tech summer undergraduate packaging research and engineering experience for minorities

    Science.gov (United States)

    May, Gary S.

    1996-07-01

    The Georgia Tech SUmmer Undergraduate Packaging Research and Engineering Experience for Minorities (GT-SUPREEM) is an eight-week summer program designed to attract qualified minority students to pursue graduate degrees in packaging- related disciplines. The program is conducted under the auspices of the Georgia Tech Engineering Research Center in Low-Cost Electronic Packaging, which is sponsored by the National Science Foundation. In this program, nine junior and senior level undergraduate students are selected on a nationwide basis and paired with a faculty advisor to undertake research projects in the Packaging Research CEnter. The students are housed on campus and provided with a $DLR3,000 stipend and a travel allowance. At the conclusion of the program, the students present both oral and written project summaries. It is anticipated that this experience will motivate these students to become applicants for graduate study in ensuring years. This paper will provide an overview of the GT-SUPREEM program, including student research activities, success stories, lessons learned, and overall program outlook.

  6. Engineering and management experience at Texas A&M Transportation Institute

    Science.gov (United States)

    Chowdhury, Arif Tahjibul

    This manuscript presents the author's engineering and management experience during his internship in the Materials and Pavements (M&P) Division at the Texas A&M Transportation Institute (TTI), and is a record of study for the Doctor of Engineering at Texas A&M University. Through this internship, he met his established internship objectives of gaining technical knowledge as well as knowledge and skills in project management, organizational communication, and quality management of pavement condition data, and of attaining professional development. In meeting these objectives, the author describes the history, mission, and organizational structure of his workplace. He also presents his experience of developing and delivering a two-week training course on pavement design and construction in Kosovo. Participating in a number of professional development training courses and other activities prepared him for working as an engineering manager. These activities include Delta-T leadership training, an instructor development course, a time management and organizational skills course, and the M&P Division lecture series. Leadership and skills learned through the Delta-T program were beneficial for the employee as well as the employer. For the class project, the author and his teammates performed a study dealing with improving TTI's deliverables. The Delta-T team composed a report summarizing their efforts of examining the current state of TTI's project deliverables, the deliverables' shortcomings, and potential enhancements to expand the deliverables' appeal to additional types of potential users outside the traditional research community. The team also developed a prototype web-based model of deliverables and presented some implementation recommendations. Participating in the Texas Department of Transportation's (TxDOT's) pavement surface distress data collection program enabled the author to become familiar with pavement distress data quality management and thus attain the

  7. Differential Experiences of Women and Minority Engineering Students in a Cooperative Education Program

    Science.gov (United States)

    Fifolt, Matthew M.; Abbott, Gypsy

    Although slight gains have been made in attracting women and minority students to the field of engineering, the differences are not great enough to meet current economic demands [National Academy of Sciences (2007). Rising above the gathering storm: Energizing and employing America for a brighter economic future, Washington, DC: National Academies Press]. Therefore, it has become imperative that colleges and universities increase efforts to both recruit and retain these students who express interest in the STEM fields [National Science Foundation (2006), Women, minorities, and persons with disabilities in science and engineering, NSF 4-311, Arlington, VA: NSF]. In engineering, one promising venue for students to gain professional experience as part of their undergraduate training is through cooperative education (co-op). However, there is a dearth of information in the research literature regarding how co-op programs can be structured to address the needs of diverse students. There is consensus, however, about one aspect of addressing the needs of diverse students, namely, mentoring and role models are key strategies for success. In this study, a mixed methods design was used to examine students' perceptions of mentoring in a cooperative education program in a southeastern university. Using Noe's [Noe, R. (1988). An investigation of the determinants of successful assigned mentoring relationships. Personnel Psychology, 1, 457-479] mentoring functions scales, which described psychosocial and career-related support, research findings indicated a statistically significant difference between gender and the psychosocial aspect of mentoring. Analysis of the qualitative data further confirmed differences in cooperative education experiences with respect to both gender and ethnicity.

  8. Studying neutrino properties in the future LENA experiment

    International Nuclear Information System (INIS)

    Wurm, Michael

    2013-01-01

    LENA (Low Energy Neutrino Astronomy) is a next-generation neutrino detector based on 50 kt of liquid scintillator. The low detection threshold, the good energy resolution and the potent background discrimination inherent to liquid scintillator make LENA a versatile observatory for astrophysical and terrestrial neutrinos. The present contribution highlights LENA's capabilities for studying neutrino properties based on both natural and artificial sources

  9. Thermophysical properties: some experience in research, development and applications

    International Nuclear Information System (INIS)

    Wagner, P.; Acton, R.U.

    1977-01-01

    Accurate measurements of thermophysical properties, understanding exactly any use requirements, and understanding the behavior of the material are all potential ingredients for in-depth research and development projects. The work reported here is but a brief description of some of the many LASL and SLA projects and their chain-branching manifestations

  10. Development and use of data base on mechanical properties of materials in power engineering

    International Nuclear Information System (INIS)

    Popov, A.A.; Shchukina, E.G.; Karaev, A.B.

    1987-01-01

    The structure of a data base on the properties of materials used in reactor engineering is considered. The data base presents a factographic automated data retrieval system, containing test results on the 15Kh2NMFA, 15Kh2NMFA-A, 15Kh2MFA, 10GN2MFA, 22K reactor vessel steels and also the data on the A533, A508 and A304 steels taken from literature. The system is realized using the VAN6 minicomputer and operates in a dialogue mode. Software of the system is arranged by module scheme and realized using the BASIC language. Results of tensile, impact, hardness, fatigue, brittle hardness, radiation resistance, high-temperature strength and heat-resistance tests and data on the thermal properties of the alloys are introduced into the system. Prior to the input in the system the information is subjected to additional expert analysis for completeness and authenticity. The main function of the data base considered consists in the systematization of a large volume of experimental data, which envisages arbitrary retrieval and subsequent analysis using statistical methods. The system contains approximately 15 thousand records on magnetic discs. The total volume of the store is 20 M byte. The system capabilities are demonstrated when analyzing the effects of aalloying additions on mechanical properties of the 15Kh2NMFA steel

  11. Studying of the combined salts effect on the engineering properties of clayey soil

    Directory of Open Access Journals (Sweden)

    Al-Obaidi Anwar

    2018-01-01

    Full Text Available In recent years, a number of studies had been performed to investigate the effect of pore water chemistry on the strength and compressibility characteristics of soil. Although the effect of chloride and sulfates salts separately in pore fluids on the geotechnical properties of soil seems to be well understood, but the influence of combined effect of sulfates and chlorides in pore water on the behavior of soil is still unclear mostly due to the limited numbers of studies as well as the complexity of processes that may occur in soil (with the presence of salts in pore water-soil interaction. Southern regions of Iraq, especially Basra suffers from low water levels in the summer season in addition to the lack of rain water, which causes a significant increase of salt in the Shatt al Arab. Water salinity continues to increase with time. To investigate the combined impacts of water salinity on the behavior of clayey soils, the basic characteristics of the soil brought from Al-Nahrawan site was studied. Chemical methods were done with three types of water (distilled, water of highly saline as Shatt Al-Arab water and water of Tarmiya as moderate saline water. The effect of water salinity on the geotechnical properties of fine grain soil was investigated. Different laboratory tests such as Atterberg limits, standard compaction, consolidation and shear strength of soil .Results showed that the presence of perceptible amounts of dissolved salts in water can lead to changes in the engineering properties of the soil.

  12. Hydrogels for lung tissue engineering: Biomechanical properties of thin collagen-elastin constructs.

    Science.gov (United States)

    Dunphy, Siobhán E; Bratt, Jessica A J; Akram, Khondoker M; Forsyth, Nicholas R; El Haj, Alicia J

    2014-10-01

    In this study, collagen-elastin constructs were prepared with the aim of producing a material capable of mimicking the mechanical properties of a single alveolar wall. Collagen has been used in a wide range of tissue engineering applications; however, due to its low mechanical properties its use is limited to non load-bearing applications without further manipulation using methods such as cross-linking or mechanical compression. Here, it was hypothesised that the addition of soluble elastin to a collagen hydrogel could improve its mechanical properties. Hydrogels made from collagen only and collagen plus varying amounts elastin were prepared. Young׳s modulus of each membrane was measured using the combination of a non-destructive indentation and a theoretical model previously described. An increase in Young׳s modulus was observed with increasing concentration of elastin. The use of non-destructive indentation allowed for online monitoring of the elastic moduli of cell-seeded constructs over 8 days. The addition of lung fibroblasts into the membrane increased the stiffness of the hydrogels further and cell-seeded collagen hydrogels were found to have a stiffness equal to the theoretical value for a single alveolar wall (≈5kPa). Through provision of some of the native extracellular matrix components of the lung parenchyma these scaffolds may be able to provide an initial building block toward the regeneration of new functional lung tissue. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Preparation and properties of polyvinyl alcohol (PVA) and hydroxylapatite (HA) hydrogels for cartilage tissue engineering.

    Science.gov (United States)

    Yuan, F; Ma, M; Lu, L; Pan, Z; Zhou, W; Cai, J; Luo, S; Zeng, W; Yin, F

    2017-05-20

    A novel bioactive hydrogel for cartilage tissue based on polyvinyl alcohol (PVA) and hydroxylapatite (HA) were prepared, the effects of its component contents on the mechanical properties and microstructure of the hydrogel were investigated. The important properties of the scaffold composites, such as density, porosity, compressive modulus and microstructure were studied and analyzed through various measurements and methods. The biodegradability of hydrogel was evaluated by soaking the samples into artificial degradation solution at body temperature (36 - 37 oC) in vitro. Experimental results showed that the PVA/HA hydrogels had a density of 0.572 - 0.683 g/cm3, a porosity of 63.25 - 96.14% and a compressive modulus of 5.62 - 8.24 MP. The HA compound in the hydrogels enhanced the biodegradation significantly and linearly increased the rate of biodegradation by 2.3 - 8.5 %. The compressive modulus of PVA/HA exhibited a linear reduce to 0.86 - 1.53 MP with the time of degradation. The scaffold composites PVA/HA possess a high porosity, decent compressive modulus and good biodegradability. After further optimizing the structure and properties, this composite might be considered as novel hydrogel biomaterials to be applied in the field of cartilage tissue engineering.

  14. Engineering CNDP's of dendrimers containing phosphorous interior compositions to produce new emerging properties

    Science.gov (United States)

    Caminade, Anne-Marie; Majoral, Jean-Pierre

    2018-03-01

    Phosphorus-containing dendrimers are defined as dendrimers having at least one phosphorus atom at each branching point. In this review, we will show how phosphorhydrazone dendrimers can be modified at will at the level of the core and of the branches, to afford specific properties, such as fluorescence to image biological events. Accelerated methods of synthesis of phosphorus (one step for one generation) will be also displayed, as well as the specific reactivity of P=N-P=S linkages obtained in most of these accelerated method of synthesis, which has led to particularly original dendritic architectures, such as dendrons included in dendrimers. Finally, we will display how modifications of the internal structure of a series of dendrimers having the same type and number of terminal functions can deeply modify their biological anti-inflammatory properties. Among the six critical nanoscale design parameters (CNDP), we will show how two of them, i.e., architecture and elemental composition, have been particularly engineered to modify phosphorus-containing dendrimers, in order to fulfill the desired properties.

  15. Combined Cycle Engine Large-Scale Inlet for Mode Transition Experiments: System Identification Rack Hardware Design

    Science.gov (United States)

    Thomas, Randy; Stueber, Thomas J.

    2013-01-01

    The System Identification (SysID) Rack is a real-time hardware-in-the-loop data acquisition (DAQ) and control instrument rack that was designed and built to support inlet testing in the NASA Glenn Research Center 10- by 10-Foot Supersonic Wind Tunnel. This instrument rack is used to support experiments on the Combined-Cycle Engine Large-Scale Inlet for Mode Transition Experiment (CCE? LIMX). The CCE?LIMX is a testbed for an integrated dual flow-path inlet configuration with the two flow paths in an over-and-under arrangement such that the high-speed flow path is located below the lowspeed flow path. The CCE?LIMX includes multiple actuators that are designed to redirect airflow from one flow path to the other; this action is referred to as "inlet mode transition." Multiple phases of experiments have been planned to support research that investigates inlet mode transition: inlet characterization (Phase-1) and system identification (Phase-2). The SysID Rack hardware design met the following requirements to support Phase-1 and Phase-2 experiments: safely and effectively move multiple actuators individually or synchronously; sample and save effector control and position sensor feedback signals; automate control of actuator positioning based on a mode transition schedule; sample and save pressure sensor signals; and perform DAQ and control processes operating at 2.5 KHz. This document describes the hardware components used to build the SysID Rack including their function, specifications, and system interface. Furthermore, provided in this document are a SysID Rack effectors signal list (signal flow); system identification experiment setup; illustrations indicating a typical SysID Rack experiment; and a SysID Rack performance overview for Phase-1 and Phase-2 experiments. The SysID Rack described in this document was a useful tool to meet the project objectives.

  16. Study of effects of engine oil additives on the properties of fluorelastomers; Fusso gomu ni oyobosu engine yu tenkazai no eikyo chosa

    Energy Technology Data Exchange (ETDEWEB)

    Kurono, K; Owaki, M; Suzuki, Y; Akiyama, K; Shionoya, M [Toyota Motor Corp., Aichi (Japan)

    1997-10-01

    Fluoroelastmers are well known for their resistance to heat and fluids and have become major material for crankcase oil sealers. On the other hand new additive formulations are developed for engine lubricants used for fuel economic gasoline engines. In this paper the effects of those additives on properties of fluoroelastmers are investigated. The results of the immersion tests of both test plaques and oil sealer products indicates that dithiocarbamates friction modifier have hardening effects on fluoroelastomers. The fluoroelastmer deterioration mechanism is presumed by analysis of elastmer samples after immersion in oil. 6 refs., 9 figs., 3 tabs.

  17. Operating experiences since rise-to-power test in high temperature engineering test reactor (HTTR)

    International Nuclear Information System (INIS)

    Tochio, Daisuke; Watanabe, Shuji; Motegi, Toshihiro; Kawano, Shuichi; Kameyama, Yasuhiko; Sekita, Kenji; Kawasaki, Kozo

    2007-03-01

    The rise-to-power test of the High Temperature Engineering Test Reactor (HTTR) was actually started in April 2000. The rated thermal power of 30MW and the rated reactor outlet coolant temperature of 850degC were achieved in the middle of Dec. 2001. After that, the reactor thermal power of 30MW and the reactor outlet coolant temperature of 950degC were achieved in the final rise-to-power test in April 2004. After receiving the operation licensing at 850degC, the safety demonstration tests have conducted to demonstrate inherent safety features of the HTGRs as well as to obtain the core and plant transient data for validation of safety analysis codes and for establishment of safety design and evaluation technologies. This paper summarizes the HTTR operating experiences for six years from start of the rise-to-power test that are categorized into (1) Operating experiences related to advanced gas-cooled reactor design, (2) Operating experiences for improvement of the performance, (3) Operating experiences due to fail of system and components. (author)

  18. Crack path predictions and experiments in plane structures considering anisotropic properties and material interfaces

    Directory of Open Access Journals (Sweden)

    P.O. Judt

    2015-10-01

    Full Text Available In many engineering applications special requirements are directed to a material's fracture behavior and the prediction of crack paths. Especially if the material exhibits anisotropic elastic properties or fracture toughnesses, e.g. in textured or composite materials, the simulation of crack paths is challenging. Here, the application of path independent interaction integrals (I-integrals, J-, L- and M-integrals is beneficial for an accurate crack tip loading analysis. Numerical tools for the calculation of loading quantities using these path-invariant integrals are implemented into the commercial finite element (FE-code ABAQUS. Global approaches of the integrals are convenient considering crack tips approaching other crack faces, internal boundaries or material interfaces. Curved crack faces require special treatment with respect to integration contours. Numerical crack paths are predicted based on FE calculations of the boundary value problem in connection with an intelligent adaptive re-meshing algorithm. Considering fracture toughness anisotropy and accounting for inelastic effects due to small plastic zones in the crack tip region, the numerically predicted crack paths of different types of specimens with material interfaces and internal boundaries are compared to subcritically grown paths obtained from experiments.

  19. Experiments and parametric studies on 3D metallic auxetic metamaterials with tuneable mechanical properties

    International Nuclear Information System (INIS)

    Ren, Xin; Shen, Jianhu; Ghaedizadeh, Arash; Min Xie, Yi; Tian, Hongqi

    2015-01-01

    Auxetic metamaterials are synthetic materials with microstructures engineered to achieve negative Poisson’s ratios. Auxetic metamaterials are of great interest because of their unusual properties and various potential applications. However, most of the previous research has been focused on auxetic behaviour of elastomers under elastic deformation. Inspired by our recent finding of the loss of auxetic behaviour in metallic auxetic metamaterials, a systematic experimental and numerical investigation has been carried out to explore the mechanism behind this phenomenon. Using an improved methodology of generating buckling-induced auxetic metamaterials, several samples of metallic auxetic metamaterials have been fabricated using a 3D printing technique. The experiments on those samples have revealed the special features of auxetic behaviour for metallic auxetic metamaterials and proved the effectiveness of our structural modification. Parametric studies have been performed through experimentally validated finite element models to explore the auxetic performance of the designed metallic metamaterials. It is found that the auxetic performance can be tuned by the geometry of microstructures, and the strength and stiffness can be tuned by the plasticity of the base material while maintaining the auxetic performance. (paper)

  20. Exploring the Properties of Genetically Engineered Silk-Elastin-Like Protein Films.

    Science.gov (United States)

    Machado, Raul; da Costa, André; Sencadas, Vitor; Pereira, Ana Margarida; Collins, Tony; Rodríguez-Cabello, José Carlos; Lanceros-Méndez, Senentxu; Casal, Margarida

    2015-12-01

    Free standing films of a genetically engineered silk-elastin-like protein (SELP) were prepared using water and formic acid as solvents. Exposure to methanol-saturated air promoted the formation of aggregated β-strands rendering aqueous insolubility and improved the mechanical properties leading to a 10-fold increase in strain-to-failure. The films were optically clear with resistivity values similar to natural rubber and thermally stable up to 180 °C. Addition of glycerol showed to enhance the flexibility of SELP/glycerol films by interacting with SELP molecules through hydrogen bonding, interpenetrating between the polymer chains and granting more conformational freedom. This detailed characterization provides cues for future and unique applications using SELP based biopolymers. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Engineering properties of sunflower seed: Effect of dehulling and moisture content

    Directory of Open Access Journals (Sweden)

    Mudasir Ahmad Malik

    2016-12-01

    Full Text Available The study diagnosed engineering properties on varying moisture content of sunflower seed and kernel from 7.6 to 25% (wet basis. On increasing moisture, dimensional values increased for both seed and kernel. Bulk density, true density and porosity were found higher for kernel as compared to seed at each moisture content. On increasing the moisture content from 7.6 to 25%, true density, porosity and thousand kernel weight increased. Coefficient of static friction on plywood was found maximum for kernel at 25% moisture content, while it was minimum for seed on glass at 7.6% moisture content. The angle of repose was maximum for kernel as compared to seed. Initial cracking force, average rupture force and average rupture energy for seed and kernel decreased with an increase in the moisture content. The kernel was found to be more resistant to initial cracking than seed.

  2. Models for predicting the mass of lime fruits by some engineering properties.

    Science.gov (United States)

    Miraei Ashtiani, Seyed-Hassan; Baradaran Motie, Jalal; Emadi, Bagher; Aghkhani, Mohammad-Hosein

    2014-11-01

    Grading fruits based on mass is important in packaging and reduces the waste, also increases the marketing value of agricultural produce. The aim of this study was mass modeling of two major cultivars of Iranian limes based on engineering attributes. Models were classified into three: 1-Single and multiple variable regressions of lime mass and dimensional characteristics. 2-Single and multiple variable regressions of lime mass and projected areas. 3-Single regression of lime mass based on its actual volume and calculated volume assumed as ellipsoid and prolate spheroid shapes. All properties considered in the current study were found to be statistically significant (ρ lime based on minor diameter and first projected area are the most appropriate models in the first and the second classifications, respectively. In third classification, the best model was obtained on the basis of the prolate spheroid volume. It was finally concluded that the suitable grading system of lime mass is based on prolate spheroid volume.

  3. Manufacturing and material properties of forgings for reactor pressure vessel of high temperature engineering test reactor

    International Nuclear Information System (INIS)

    Sato, I.; Suzuki, K.

    1994-01-01

    For the reactor pressure vessel (RPV) of high temperature engineering test reactor (HTTR) which has been developed by Japan Atomic Energy Research Institute (JAERI), 2 1/4Cr-1Mo steel is used first in the world. Material confirmation test has been carried out to demonstrate good applicability of forged low Si 2 1/4Cr-1Mo steel to the RPV of HTTR. Recently, JSW has succeeded in the manufacturing of large size ring forgings and large size forged cover dome integrated with nozzles for stand pipe for the RPV. This paper describes the results of the material confirmation test as well as the manufacturing and material properties of the large forged cover dome integrated with nozzles for stand pipe. (orig.)

  4. Preparation and Properties of 3D Printed Alginate–Chitosan Polyion Complex Hydrogels for Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Qiongqiong Liu

    2018-06-01

    Full Text Available Three-dimensional (3D printing holds great potential for preparing sophisticated scaffolds for tissue engineering. As a result of the shear thinning properties of an alginate solution, it is often used as 3D printing ink. However, it is difficult to prepare scaffolds with complexity structure and high fidelity, because the alginate solution has a low viscosity and alginate hydrogels prepared with Ca2+ crosslinking are mechanically weak. In this work, chitosan powders were dispersed and swelled in an alginate solution, which could effectively improve the viscosity of an alginate solution by 1.5–4 times. With the increase of chitosan content, the shape fidelity of the 3D printed alginate–chitosan polyion complex (AlCh PIC hydrogels were improved. Scanning electron microscope (SEM photographs showed that the lateral pore structure of 3D printed hydrogels was becoming more obvious. As a result of the increased reaction ion pairs in comparison to the alginate hydrogels that were prepared with Ca2+ crosslinking, AlCh PIC hydrogels were mechanically strong, and the compression stress of hydrogels at a 90% strain could achieve 1.4 MPa without breaking. In addition, human adipose derived stem cells (hASCs adhered to the 3D printed AlCh PIC hydrogels and proliferated with time, which indicated that the obtained hydrogels were biocompatible and could potentially be used as scaffolds for tissue engineering.

  5. Photoelectric schlieren method used to study the properties of diesel engine injection systems

    International Nuclear Information System (INIS)

    Reznicek, R.

    1987-01-01

    The time dependence of the fuel flow rate issuing from the injector nozzle represents very important information concerning the properties of Diesel engine injection systems. By analysing the delivery rate, it is possible to judge a new design, and the modifications and adjustments of Diesel engine injection systems. A number of devices for measuring the delivery rate, frequently founded on mechanical principles, have also been constructed. Mechanical methods are laborious, require complicated measuring instruments, and the analysis of the results is quite tedious. For investigating the delivery rate, one can also use the intensity of the luminous flux of the light ray which is intersected, and consequently its intensity decreased, by the flow of the delivered fuel. The schlieren method can be used for this purpose, employing a thin beam of parallel light rays and a photoelectric sensor placed immediately beyond the cut-off slit. After adjustment and calibration, the variations of the original electric signal represent the time variation of the delivery rate by the nozzle

  6. Growth Factor Stimulation Improves the Structure and Properties of Scaffold-Free Engineered Auricular Cartilage Constructs

    Science.gov (United States)

    Rosa, Renata G.; Joazeiro, Paulo P.; Bianco, Juares; Kunz, Manuela; Weber, Joanna F.; Waldman, Stephen D.

    2014-01-01

    The reconstruction of the external ear to correct congenital deformities or repair following trauma remains a significant challenge in reconstructive surgery. Previously, we have developed a novel approach to create scaffold-free, tissue engineering elastic cartilage constructs directly from a small population of donor cells. Although the developed constructs appeared to adopt the structural appearance of native auricular cartilage, the constructs displayed limited expression and poor localization of elastin. In the present study, the effect of growth factor supplementation (insulin, IGF-1, or TGF-β1) was investigated to stimulate elastogenesis as well as to improve overall tissue formation. Using rabbit auricular chondrocytes, bioreactor-cultivated constructs supplemented with either insulin or IGF-1 displayed increased deposition of cartilaginous ECM, improved mechanical properties, and thicknesses comparable to native auricular cartilage after 4 weeks of growth. Similarly, growth factor supplementation resulted in increased expression and improved localization of elastin, primarily restricted within the cartilaginous region of the tissue construct. Additional studies were conducted to determine whether scaffold-free engineered auricular cartilage constructs could be developed in the 3D shape of the external ear. Isolated auricular chondrocytes were grown in rapid-prototyped tissue culture molds with additional insulin or IGF-1 supplementation during bioreactor cultivation. Using this approach, the developed tissue constructs were flexible and had a 3D shape in very good agreement to the culture mold (average error tissue structure and 3D shape of the external ear, future studies will be aimed assessing potential changes in construct shape and properties after subcutaneous implantation. PMID:25126941

  7. A novel bioreactor to simulate urinary bladder mechanical properties and compliance for bladder functional tissue engineering.

    Science.gov (United States)

    Wei, Xin; Li, Dao-bing; Xu, Feng; Wang, Yan; Zhu, Yu-chun; Li, Hong; Wang, Kun-jie

    2011-02-01

    Bioreactors are pivotal tools for generating mechanical stimulation in functional tissue engineering study. This study aimed to create a bioreactor that can simulate urinary bladder mechanical properties, and to investigate the effects of a mechanically stimulated culture on urothelial cells and bladder smooth muscle cells. We designed a bioreactor to simulate the mechanical properties of bladder. A pressure-record system was used to evaluate the mechanical properties of the bioreactor by measuring the pressure in culture chambers. To test the biocompatibility of the bioreactor, viabilities of urothelial cells and smooth muscle cells cultured in the bioreactor under static and mechanically changed conditions were measured after 7-day culture. To evaluate the effect of mechanical stimulations on the vital cells, urethral cells and smooth muscle cells were cultured in the simulated mechanical conditions. After that, the viability and the distribution pattern of the cells were observed and compared with cells cultured in non-mechanical stimulated condition. The bioreactor system successfully generated waveforms similar to the intended programmed model while maintaining a cell-seeded elastic membrane between the chambers. There were no differences between viabilities of urothelial cells ((91.90 ± 1.22)% vs. (93.14 ± 1.78)%, P > 0.05) and bladder smooth muscle cells ((93.41 ± 1.49)% vs. (92.61 ± 1.34)%, P > 0.05). The viability of cells and tissue structure observation after cultured in simulated condition showed that mechanical stimulation was the only factor affected cells in the bioreactor and improved the arrangement of cells on silastic membrane. This bioreactor can effectively simulate the physiological and mechanical properties of the bladder. Mechanical stimulation is the only factor that affected the viability of cells cultured in the bioreactor. The bioreactor can change the growth behavior of urothelial cells and bladder smooth muscle cells, resulting in

  8. Biaxial Stretch Improves Elastic Fiber Maturation, Collagen Arrangement, and Mechanical Properties in Engineered Arteries.

    Science.gov (United States)

    Huang, Angela H; Balestrini, Jenna L; Udelsman, Brooks V; Zhou, Kevin C; Zhao, Liping; Ferruzzi, Jacopo; Starcher, Barry C; Levene, Michael J; Humphrey, Jay D; Niklason, Laura E

    2016-06-01

    Tissue-engineered blood vessels (TEVs) are typically produced using the pulsatile, uniaxial circumferential stretch to mechanically condition and strengthen the arterial grafts. Despite improvements in the mechanical integrity of TEVs after uniaxial conditioning, these tissues fail to achieve critical properties of native arteries such as matrix content, collagen fiber orientation, and mechanical strength. As a result, uniaxially loaded TEVs can result in mechanical failure, thrombus, or stenosis on implantation. In planar tissue equivalents such as artificial skin, biaxial loading has been shown to improve matrix production and mechanical properties. To date however, multiaxial loading has not been examined as a means to improve mechanical and biochemical properties of TEVs during culture. Therefore, we developed a novel bioreactor that utilizes both circumferential and axial stretch that more closely simulates loading conditions in native arteries, and we examined the suture strength, matrix production, fiber orientation, and cell proliferation. After 3 months of biaxial loading, TEVs developed a formation of mature elastic fibers that consisted of elastin cores and microfibril sheaths. Furthermore, the distinctive features of collagen undulation and crimp in the biaxial TEVs were absent in both uniaxial and static TEVs. Relative to the uniaxially loaded TEVs, tissues that underwent biaxial loading remodeled and realigned collagen fibers toward a more physiologic, native-like organization. The biaxial TEVs also showed increased mechanical strength (suture retention load of 303 ± 14.53 g, with a wall thickness of 0.76 ± 0.028 mm) and increased compliance. The increase in compliance was due to combinatorial effects of mature elastic fibers, undulated collagen fibers, and collagen matrix orientation. In conclusion, biaxial stretching is a potential means to regenerate TEVs with improved matrix production, collagen organization, and mechanical

  9. Understanding performance properties of chemical engines under a trade-off optimization: Low-dissipation versus endoreversible model

    Science.gov (United States)

    Tang, F. R.; Zhang, Rong; Li, Huichao; Li, C. N.; Liu, Wei; Bai, Long

    2018-05-01

    The trade-off criterion is used to systemically investigate the performance features of two chemical engine models (the low-dissipation model and the endoreversible model). The optimal efficiencies, the dissipation ratios, and the corresponding ratios of the dissipation rates for two models are analytically determined. Furthermore, the performance properties of two kinds of chemical engines are precisely compared and analyzed, and some interesting physics is revealed. Our investigations show that the certain universal equivalence between two models is within the framework of the linear irreversible thermodynamics, and their differences are rooted in the different physical contexts. Our results can contribute to a precise understanding of the general features of chemical engines.

  10. Is It "Writing on Water" or "Strike It Rich?" The Experiences of Prospective Teachers in Using Search Engines

    Science.gov (United States)

    Sahin, Abdurrahman; Cermik, Hulya; Dogan, Birsen

    2010-01-01

    Information searching skills have become increasingly important for prospective teachers with the exponential growth of learning materials on the web. This study is an attempt to understand the experiences of prospective teachers with search engines through metaphoric images and to further investigate whether their experiences are related to the…

  11. Emulation-Based Virtual Laboratories: A Low-Cost Alternative to Physical Experiments in Control Engineering Education

    Science.gov (United States)

    Goodwin, G. C.; Medioli, A. M.; Sher, W.; Vlacic, L. B.; Welsh, J. S.

    2011-01-01

    This paper argues the case for emulation-based virtual laboratories in control engineering education. It demonstrates that such emulation experiments can give students an industrially relevant educational experience at relatively low cost. The paper also describes a particular emulation-based system that has been developed with the aim of giving…

  12. Investigation on mechanical properties of basalt composite fabrics (experiment study)

    Science.gov (United States)

    Talebi Mazraehshahi, H.; Zamani, H.

    2010-06-01

    To fully appreciate the role and application of composite materials to structures, correct understanding of mechanical behaviors required for selection of optimum material. Fabric reinforced composites are composed of a matrix that is reinforced with pliable fabric, glass fabric is most popular reinforcement for different application specially in aircraft structure, although other fabric material are also used. At this study new fabric material called basalt with epoxy resin introduced and mechanical behaviors of this material investigated from view point of testing. For this study two type of fabric with different thickness used. Comparison between this composite reinforcement with popular reinforcement as carbon, glass, kevlar performed. To determine mechanical properties of epoxy based basalt fabric following test procedure performed : 1). Tensile testing according to ASTM D3039 in 0° and 90° direction to find ultimate strength in tension and shear, modulus of elasticity, elangation and ultimate strain. 2). Compression testing according to EN 2850 ultimate compression strength and maximum deformation under compression loading. 3). Shear testing according to ASTM D3518-94 to find in plane shear response of polymer matrix composites materials. 4). Predict flexural properties of sandwich construction which manufactured from basalt facing with PVC foam core according to ASTM C393-94. Material strength properties must be based on enough tests of material to meet the test procedure specifications [1]. For this reason six specimens were manufactured for testing and the tests were performed on them using an INSTRON machine model 5582. In the study, the effect of percent of resin in basalt reinforced composite was investigated. Also the weights of the ballast based composites with different percent of resin were measured with conventional composites. As the weight is an important parameter in aerospace industry when the designer wants to replace one material with

  13. Investigation on mechanical properties of basalt composite fabrics (experiment study

    Directory of Open Access Journals (Sweden)

    Talebi Mazraehshahi H.

    2010-06-01

    Full Text Available To fully appreciate the role and application of composite materials to structures, correct understanding of mechanical behaviors required for selection of optimum material. Fabric reinforced composites are composed of a matrix that is reinforced with pliable fabric, glass fabric is most popular reinforcement for different application specially in aircraft structure, although other fabric material are also used. At this study new fabric material called basalt with epoxy resin introduced and mechanical behaviors of this material investigated from view point of testing. For this study two type of fabric with different thickness used. Comparison between this composite reinforcement with popular reinforcement as carbon, glass, kevlar performed. To determine mechanical properties of epoxy based basalt fabric following test procedure performed : 1. Tensile testing according to ASTM D3039 in 0° and 90° direction to find ultimate strength in tension and shear, modulus of elasticity, elangation and ultimate strain. 2. Compression testing according to EN 2850 ultimate compression strength and maximum deformation under compression loading. 3. Shear testing according to ASTM D3518-94 to find in plane shear response of polymer matrix composites materials. 4. Predict flexural properties of sandwich construction which manufactured from basalt facing with PVC foam core according to ASTM C393-94. Material strength properties must be based on enough tests of material to meet the test procedure specifications [1]. For this reason six specimens were manufactured for testing and the tests were performed on them using an INSTRON machine model 5582. In the study, the effect of percent of resin in basalt reinforced composite was investigated. Also the weights of the ballast based composites with different percent of resin were measured with conventional composites. As the weight is an important parameter in aerospace industry when the designer wants to replace one

  14. Dynamic Testing of the NASA Hypersonic Project Combined Cycle Engine Testbed for Mode Transition Experiments

    Science.gov (United States)

    2011-01-01

    NASA is interested in developing technology that leads to more routine, safe, and affordable access to space. Access to space using airbreathing propulsion systems has potential to meet these objectives based on Airbreathing Access to Space (AAS) system studies. To this end, the NASA Fundamental Aeronautics Program (FAP) Hypersonic Project is conducting fundamental research on a Turbine Based Combined Cycle (TBCC) propulsion system. The TBCC being studied considers a dual flow-path inlet system. One flow-path includes variable geometry to regulate airflow to a turbine engine cycle. The turbine cycle provides propulsion from take-off to supersonic flight. The second flow-path supports a dual-mode scramjet (DMSJ) cycle which would be initiated at supersonic speed to further accelerate the vehicle to hypersonic speed. For a TBCC propulsion system to accelerate a vehicle from supersonic to hypersonic speed, a critical enabling technology is the ability to safely and effectively transition from the turbine to the DMSJ-referred to as mode transition. To experimentally test methods of mode transition, a Combined Cycle Engine (CCE) Large-scale Inlet testbed was designed with two flow paths-a low speed flow-path sized for a turbine cycle and a high speed flow-path designed for a DMSJ. This testbed system is identified as the CCE Large-Scale Inlet for Mode Transition studies (CCE-LIMX). The test plan for the CCE-LIMX in the NASA Glenn Research Center (GRC) 10- by 10-ft Supersonic Wind Tunnel (10x10 SWT) is segmented into multiple phases. The first phase is a matrix of inlet characterization (IC) tests to evaluate the inlet performance and establish the mode transition schedule. The second phase is a matrix of dynamic system identification (SysID) experiments designed to support closed-loop control development at mode transition schedule operating points for the CCE-LIMX. The third phase includes a direct demonstration of controlled mode transition using a closed loop control

  15. Thermodynamic properties of a smectite and an illite: comparison between solubility experiments and calorimetric results

    International Nuclear Information System (INIS)

    Gailhanou, H.; Gaboreau, S.; Gaucher, E.C.; Blanc, P.; Rogez, J.; Olives, J.; Amouric, M.; Van Miltenburg, J.C.; Michau, N.; Giffaut, E.

    2010-01-01

    Document available in extended abstract form only. In the context of nuclear waste repositories in argillaceous formations, it is necessary to assess the geochemical behaviour of natural and engineered clay barriers, namely by the stability of clay minerals over long periods of time. However, thermodynamic data of clay minerals, which are required for geochemical modelling, are still poorly known. The present study aims to improve our comprehension of clay mineral stability. The thermodynamic properties of smectite MX-80 and illite IMt-2 (Silver Hill, Montana) have already been determined using calorimetric methods between 0 K and 520 K, under both dried and hydrated states in the case of smectite. In parallel, solubility experiments were carried out in order to determine the solubility products of the clay minerals. Such experiments require some particular precautions as published by May et al. (1986) and Aja and Rosenberg (1992). According to these authors, it is namely important to reach the equilibrium from both under and over saturation and to characterize from a mineralogical point of view the end products. Taking advantage of previous calorimetric measurements, we propose to compare the solubility products obtained here from dissolution experiments with respect to calorimetry results, in order to assess the equilibrium achievement for the solubility experiments. The study is integrated in the Thermochimie project, which aims to provide a consistent thermodynamic database (Thermochimie) for modelling purposes. This work dealing with a smectite and an illite is being completed by the study of a set of typical clays, selected to be well-representative of the clay group. Enthalpies of formation of the minerals were determined by isothermal dissolution calorimetry at 25 deg. C, using a HF-HNO 3 solution. They were obtained by measuring the enthalpies of dissolution of (i) the sample (clay mineral + impurities) and (ii) the oxide or hydroxide constituent mixture

  16. Incorporating geoethics into environmental engineering lectures - three years of experience from international students visiting Iceland

    Science.gov (United States)

    Finger, David C.

    2017-04-01

    Never before has human kind been facing bigger environmental challenges than today. The challenges are overwhelming: growing human population, increasing ecological footprints, accelerated climate change, severe soil degradation, eutrophication of vital fresh water resources, acidification of oceans, health threatening air pollution and rapid biodiversity loss, to name just a few. It is the task of environmental scientists to transmit established knowledge on these complex and interdisciplinary challenges while demonstrating that management and engineering solutions exist to meet these threats. In this presentation I will outline the concept of my environmental impact (EI) assessment course, where prospective engineering students can select a topic of their choice, assess the environmental impacts, discuss with relevant stakeholders and come up with innovative solutions. The course is structured in three parts: i) lecturing of theoretical methods frequently used within the EI assessment process, ii) interaction with local businesses to acquire first-hand experience and iii) hands on training by writing an EI statement on a selected topic (see link below). Over the course of three years over 70 prospective engineering students from all over the world have not only acquired environmental system understanding, but also enhanced their awareness and developed potential solutions to mitigate, compensate and reverse the persistent environmental challenges. Most importantly, during this process all involved stakeholders (students, teachers, industry partners, governmental bodies and NGO partners) will hopefully develop a mutual understanding of the above mentioned environmental challenges and engage in an open and constructive dialogue necessary to generate acceptable solutions. Link to student projects from previous years: https://fingerd.jimdo.com/teaching/courses/environmental-impact-assessment/

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

    Science.gov (United States)

    Martinez-Luaces, Victor

    2009-01-01

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

  18. Safety Research Experiment Facilities, Idaho National Engineering Laboratory, Idaho. Draft environmental statement

    International Nuclear Information System (INIS)

    1977-01-01

    This environmental statement was prepared in accordance with the National Environmental Policy Act of 1969 (NEPA) in support of the Energy Research and Development Administration's (ERDA) proposal for legislative authorization and appropriations for the Safety Research Experiment Facilities (SAREF) Project. The purpose of the proposed project is to modify some existing facilities and provide a new test facility at the Idaho National Engineering Laboratory (INEL) for conducting fast breeder reactor (FBR) safety experiments. The SAREF Project proposal has been developed after an extensive study which identified the FBR safety research needs requiring in-reactor experiments and which evaluated the capability of various existing and new facilities to meet these needs. The proposed facilities provide for the in-reactor testing of large bundles of prototypical FBR fuel elements under a wide variety of conditions, ranging from those abnormal operating conditions which might be expected to occur during the life of an FBR power plant to the extremely low probability, hypothetical accidents used in the evalution of some design options and in the assessment of the long-term potential risk associated with wide-scale deployment of the FBR

  19. Nuclear engineering laboratory self regulated power oscillation experiments at the Health Physics Research Reactor

    International Nuclear Information System (INIS)

    Miller, L.F.; Mihalczo, J.T.; Bailiff, E.G.; Woody, N.D.; Gardner, G.D.

    1983-01-01

    Self regulated power oscillation experiments with a variety of initial conditions have been performed with the ORNL Health Physics Research Reactor (HPRR) by undergraduate nuclear engineering students from The University of Tennessee for several years. These experiments demonstrate the coupling between reactor kinetics and heat transfer and show how the temperature coefficient of reactivity affects reactor behavior. A model that consists of several coupled first order nonlinear differential equations is used to calculate the temperature of the core center and surface and power as a function of time which are compared with the experimental data; also, the model is also used to study the effects of various model parameters and initial conditions on the amplitude, frequency and damping of the power and temperature oscillations. A previous paper presented some limited experimental results and demonstrated the correspondence between a simple point model and the experimental data. This paper presents the results of experiments for: (1) the initial power fixed at 9 kW with central core temperatures of 300 0 F and 500 0 F, annd (2) the initial central core temperature fixed at 500 0 F with initial powers of 6 and 8 kW

  20. Particle Engineering of Excipients for Direct Compression: Understanding the Role of Material Properties.

    Science.gov (United States)

    Mangal, Sharad; Meiser, Felix; Morton, David; Larson, Ian

    2015-01-01

    Tablets represent the preferred and most commonly dispensed pharmaceutical dosage form for administering active pharmaceutical ingredients (APIs). Minimizing the cost of goods and improving manufacturing output efficiency has motivated companies to use direct compression as a preferred method of tablet manufacturing. Excipients dictate the success of direct compression, notably by optimizing powder formulation compactability and flow, thus there has been a surge in creating excipients specifically designed to meet these needs for direct compression. Greater scientific understanding of tablet manufacturing coupled with effective application of the principles of material science and particle engineering has resulted in a number of improved direct compression excipients. Despite this, significant practical disadvantages of direct compression remain relative to granulation, and this is partly due to the limitations of direct compression excipients. For instance, in formulating high-dose APIs, a much higher level of excipient is required relative to wet or dry granulation and so tablets are much bigger. Creating excipients to enable direct compression of high-dose APIs requires the knowledge of the relationship between fundamental material properties and excipient functionalities. In this paper, we review the current understanding of the relationship between fundamental material properties and excipient functionality for direct compression.

  1. EFFECTS OF COMPACTIVE EFFORTS ON GEOTECHNICAL PROPERTIES OF SPENT ENGINE OIL CONTAMINATED LATERITE SOIL

    Directory of Open Access Journals (Sweden)

    OLUREMI, J. ROTIMI

    2017-03-01

    Full Text Available Investigation of the effects of compactive efforts and spent engine oil (SEO contamination on the geotechnical properties of lateritic soils was made. Contaminated specimens were prepared by mixing lateritic soil with up to 10 % SEO by dry weight of the soil in step concentration of 2 % and subjected to geotechnical tests. Results indicated a decrease in the fine content, decrease in liquid limit, maximum dry density (MDD and unconfined compressive strength (UCS with up to 10 % SEO content. No general trend was observed in the optimum moisture content (OMC with increasing SEO content. The MDD, OMC and UCS values increased with increase in the compactive effort. Regression analysis of the results showed that optimum moisture content, fine content and compactive effort significantly influence the soils UCS values. Analysis of variance showed that SEO and compactive effort has significant effect on the parameters with the exception in one case. The results of laboratory tests showed that geotechnical properties of the SEO contaminated soil were immensely impaired.

  2. The influence of supercritical foaming conditions on properties of polymer scaffolds for tissue engineering

    Directory of Open Access Journals (Sweden)

    Kosowska Katarzyna

    2017-12-01

    Full Text Available The results of experimental investigations into foaming process of poly(ε-caprolactone using supercritical CO2 are presented. The objective of the study was to explore the aspects of fabrication of biodegradable and biocompatible scaffolds that can be applied as a temporary three-dimensional extracellular matrix analog for cells to grow into a new tissue. The influence of foaming process parameters, which have been proven previously to affect significantly scaffold bioactivity, such as pressure (8-18 MPa, temperature (323-373 K and time of saturation (1-6 h on microstructure and mechanical properties of produced polymer porous structures is presented. The morphology and mechanical properties of considered materials were analyzed using a scanning electron microscope (SEM, x-ray microtomography (μ-CT and a static compression test. A precise control over porosity and morphology of obtained polymer porous structures by adjusting the foaming process parameters has been proved. The obtained poly(ε-caprolactone solid foams prepared using scCO2 have demonstrated sufficient mechanical strength to be applied as scaffolds in tissue engineering.

  3. Methods for Assessing Basic Particle Properties and Cytotoxicity of Engineered Nanoparticles

    Directory of Open Access Journals (Sweden)

    Olga-Ioanna Kalantzi

    2014-03-01

    Full Text Available The increasing penetration of materials and products containing engineered nanoparticles (ENPs to the market is posing many concerns regarding their environmental impacts. To assess these impacts, there is an urgent need of techniques for determining the health-related properties of ENPs and standards for assessing their toxicity. Although a wide number of systems for characterizing nanoparticles in different media (i.e., gases and liquids is already commercially available, the development of protocols for determining the cytotoxicity of ENPs is still at an infant stage, drawing upon existing knowledge from general toxicology. In this regard, differences in the preparation of ENP-containing solutions for cytotoxicity testing, as well as in the steps involved in the tests can result in significant deviations and inconsistencies between studies. In an attempt to highlight the urgent need for assessing the environmental impacts of nanotechnology, this article provides a brief overview of the existing methods for determining health-related properties of ENPs and their cytotoxicity.

  4. Exploration of the lived experiences of undergraduate science, technology, engineering, and mathematics minority students

    Science.gov (United States)

    Snead-McDaniel, Kimberly

    An expanding ethnicity gap exists in the number of students pursuing science, technology, engineering, and mathematics (STEM) careers in the United States. The National Action Council for Minorities in Engineering revealed that the number of minorities pursuing STEM degrees and careers has declined over the past few years. The specific origins of this trend are not quite evident; one variable to consider is that undergraduate minority students are failing in STEM disciplines at various levels of education from elementary to postsecondary. The failure of female and minority students to enter STEM disciplines in higher education have led various initiatives to establish programs to promote STEM disciplines among these groups. Additional funding for minority STEM programs have led to a increase in undergraduate minority students entering STEM disciplines, but the minority students' graduation rate in STEM disciplines is approximately 7% lower than the graduation of nonminority students in STEM disciplines. This phenomenological qualitative research study explores the lived experiences of underrepresented minority undergraduate college students participating in an undergraduate minority-mentoring program. The following nine themes emerged from the study: (a) competitiveness, (b) public perception, (c) dedication, (d) self-perception, (e) program activities, (f) time management, (g) exposure to career and graduate opportunities, (h) rigor in the curriculum, and (i) peer mentoring. The themes provided answers and outcomes to better support a stronger minority representation in STEM disciplines.

  5. Successful experiences in the application of Concept Maps in Engineering in Computing, Mexico

    Directory of Open Access Journals (Sweden)

    Beatriz Guardian Soto

    2013-02-01

    Full Text Available Today there is an enormous amount of work related to new models and styles of learning and instruction in the field of engineering. In the case of the engineering degree in computing that is taught in the Mexico National Polytechnic Institute (IPN, there is a working group led by an expert of international waisted whose success and work thereon, processes are reflected in this text through experiences gained in the last 8 years with students and teachers, thus generatingthe requirements and tools for the globalised world and the knowledge society in which we find ourselves. Lessons learned are in subjects as the theory of automata (TA, compilers (Cs, analysis of algorithms (AA, (R, Artificial Intelligence (AI, computer programming (P networks, degree project (PT and strategic planning (PE mainly, among others to facilitate the understanding of concepts and applications by the student and believe that through the teaching strategy using concept maps developed by j. Novak results have been favorable in dynamism, understanding and generating meaningful learning in the long term, providing well, solid elements for your professional practice. Listed proposals obtained by teachers and exercises developed by teachers and students.

  6. Cogeneration with natural gas fired internal combustion engines: Italian utility's 10 years operating experience

    International Nuclear Information System (INIS)

    Montermini, G.P.

    1992-01-01

    This paper describes the experience that AGAC, an Italian gas and water utility, has acquired in the operation of a 116 Km long district heating network serving about 40,000 inhabitants. The network is powered by a mix of methane fuelled Otto and diesel cycle engines, coal fired fluidized bed boilers, and methane fired boilers producing annually about 153,000 kW of thermal energy, 2,300 kW of cooling energy, and 28.8 million kWh of electric power. This paper reports on the performance of this system in terms of production and sales trends, equipment efficiency and compatibility with new European Communities air pollution standards

  7. Preparation of Engineering Students for Capstone Design Experience through a Microprocessors Course

    Directory of Open Access Journals (Sweden)

    Mohammed El-Abd

    2017-11-01

    Full Text Available This paper presents the outcomes of a developed methodology to handle the project component in a higher-level undergraduate course. The approach relies on providing the students the freedom to choose their own project area as well as the utilized technology. At the same time, the students have to follow certain regulation to allow for the creation of a semi-capstone experience. We illustrate how this approach has a positive effect, not only on the project outcomes at the course level, but also on the students’ performances in subsequent capstone courses. Data collected, over five consecutive course offerings, shows that this approach is an effective method to prepare engineering students for their senior design capstone courses.

  8. Engineering status of the superconducting end cap toroid magnets for the ATLAS experiment at LHC

    CERN Document Server

    Baynham, D Elwyn; Carr, F S; Courthold, M J D; Cragg, D A; Densham, C J; Evans, D; Holtom, E; Rochford, J; Sole, D; Towndrow, Edwin F; Warner, G P

    2000-01-01

    The ATLAS experiment at LHC, CERN will utilise a large, superconducting, air-cored toroid magnet system for precision muon measurements. The magnet system will consist of a long barrel and two end-cap toroids. Each end-cap toroid will contain eight racetrack coils mounted as a single cold mass in cryostat vessel of ~10 m diameter. The project has now moved from the design/specification stage into the fabrication phase. This paper presents the engineering status of the cold masses and vacuum vessels that are under fabrication in industry. Final designs of cold mass supports, cryogenic systems and control/protection systems are presented. Planning for toroid integration, test and installation is described. (3 refs).

  9. ThermoData Engine: Extension to Solvent Design and Multi-component Process Stream Property Calculations with Uncertainty Analysis

    DEFF Research Database (Denmark)

    Diky, Vladimir; Chirico, Robert D.; Muzny, Chris

    ThermoData Engine (TDE, NIST Standard Reference Databases 103a and 103b) is the first product that implements the concept of Dynamic Data Evaluation in the fields of thermophysics and thermochemistry, which includes maintaining the comprehensive and up-to-date database of experimentally measured...... property values and expert system for data analysis and generation of recommended property values at the specified conditions along with uncertainties on demand. The most recent extension of TDE covers solvent design and multi-component process stream property calculations with uncertainty analysis...... variations). Predictions can be compared to the available experimental data, and uncertainties are estimated for all efficiency criteria. Calculations of the properties of multi-component streams including composition at phase equilibria (flash calculations) are at the heart of process simulation engines...

  10. Magical properties of a 2540 km baseline superbeam experiment

    International Nuclear Information System (INIS)

    Raut, Sushant K.; Singh, Ravi Shanker; Uma Sankar, S.

    2011-01-01

    Lack of any information on the CP violating phase δ CP weakens our ability to determine neutrino mass hierarchy. Magic baseline of 7500 km was proposed to overcome this problem. However, to obtain large enough fluxes, at this very long baseline, one needs new techniques of generating high intensity neutrino beams. In this Letter, we highlight the magical properties of a 2540 km baseline. At such a baseline, using a narrow band neutrino superbeam whose no oscillation event rate peaks around the energy 3.5 GeV, we can determine neutrino mass hierarchy independently of the CP phase. For sin 2 2θ 13 ≥0.05, a very modest exposure of 10 Kiloton-years is sufficient to determine the hierarchy. For 0.02≤sin 2 2θ 13 ≤0.05, an exposure of about 100 Kiloton-years is needed.

  11. Engineering and functional properties of biodegradable pellets developed from various agro-industrial wastes using extrusion technology

    OpenAIRE

    Jan, Kulsum; Riar, C. S.; Saxena, D. C.

    2015-01-01

    Different agro-industrial wastes were mixed with different plasticizers and extruded to form the pellets to be used further for development of biodegradable molded pots. Bulk density and macro-porosity are the important engineering properties used to determine the functional characteristics of the biodegradable pellets viz., expansion volume, water solubility, product colour, flowability and compactness. Significant differences in the functional properties of pellets with varying bulk densiti...

  12. Forecasting the changes in engineering-geological properties of loess rocks by a penetration-logging method

    International Nuclear Information System (INIS)

    Saparov, A.

    1977-01-01

    Changes of volume weight, volume numidity, side friction and head resistance of loess rocks are considered. It is established, that the most perspective methods for forecasting engineering-geological properties of loess rocks are the methods of radioactivity logging and static probing. The quantitative determinations of physical and mechanical properties are made using the data of the following geophysical methods: gamma-gamma logging, neutron logging and gamma logging

  13. Predicting petrophysical properties by simultaneous inversion of seismic and reservoir engineering data

    Science.gov (United States)

    Mantilla, Andres Eduardo

    Porosity and permeability are the most difficult properties to determine in subsurface reservoir characterization, yet usually they have the largest impact on reserves and production forecasts, and consequently on the economy of a project. The difficulty of estimating them comes from the fact that porosity and permeability may vary significantly over the reservoir volume, but can only be sampled at well locations, often using different technologies at different scales of observation. An accurate estimation of the spatial distribution of porosity and permeability is of key importance, because it translates into higher success rates in infill drilling, and fewer wells required for draining the reservoir. The purpose of this thesis is to enhance the characterization of subsurface reservoirs by improving the prediction of petrophysical properties through the combination of reservoir geophysics and reservoir engineering observations and models. To fulfill this goal, I take advantage of the influence that petrophysical properties have on seismic and production data, and formulate, implement, and demonstrate the applicability of an inversion approach that integrates seismic and production-related observations with a-priori information about porosity and permeability. Being constrained by physical models and observations, the resulting estimates are appropriate for making reservoir management decisions. I use synthetic models to test the proposed inversion approach. Results from these tests show that, because of the excellent spatial coverage of seismic data, incorporating seismic-derived attributes related to petrophysical properties can significantly improve the estimates of porosity and permeability. The results also highlight the importance of using a-priori information about the relationship between porosity and permeability. The last chapters of this thesis describe a practical application of the proposed joint inversion approach. This application includes a rock

  14. Fluctuation properties of nuclear energy levels and widths: comparison of theory with experiment

    International Nuclear Information System (INIS)

    Bohigas, O.; Haq, R.U.; Pandey, A.

    1982-09-01

    We analyze the fluctuation properties of nuclear energy levels and widths with new spectrally averaged measures. A remarkably close agreement between the predictions of random-matrix theories and experiment is found

  15. Identifying the changes of geo-engineering properties of dunites due to weathering utilizing electrical resistivity tomography (ERT)

    International Nuclear Information System (INIS)

    Ündül, Ömer; Tuğrul, Atiye; Zarif, İ Halil; Özyalın, Şenol

    2015-01-01

    Weathering phenomena have an important role in many construction facilities with varying depths and grades. Due to the anisotropic and heterogeneous nature of weathering profiles of some rocks, uncertainities exist in determining the geo-engineering properties. Geo-electrical studies have been utilized to overcome such uncertainities for various subsurface conditions including the determination of boundaries between weathered and unweathered parts of different rock types.In this study, the electrical resistivity tomography (ERT) results were correlated with conventional methods in determining the effects of weathering on the geo-engineering properties of dunites. During the research, weathering grades were determined by field studies including discontinuity spacings, aperture and properties of fill materials. The detailed petrographical studies, determination of petrophysical properties (e.g. water absorption and effective porosity) and mechanical properties (e.g. unconfined compressive strength (UCS)) constitute the laboratory studies. ERT studies were carried out in a row of sixty electrodes with electrode spacings of 0.5 m utilizing a Wenner–Schlumberger configuration. According to the comparison of the inversion model sections with the weathering profiles obtained by field and laboratory studies it is concluded that the use of ERT with a Wenner–Schlumberger configuration supplies comparable data for wider subsurface areas from the view of weathering and its effect on geo-engineering properties of dunites. In addition, ERT techniques are very useful where conventional techniques are inadequate in determining the full weathering profile. (paper)

  16. Engineering and functional properties of biodegradable pellets developed from various agro-industrial wastes using extrusion technology.

    Science.gov (United States)

    Jan, Kulsum; Riar, C S; Saxena, D C

    2015-12-01

    Different agro-industrial wastes were mixed with different plasticizers and extruded to form the pellets to be used further for development of biodegradable molded pots. Bulk density and macro-porosity are the important engineering properties used to determine the functional characteristics of the biodegradable pellets viz., expansion volume, water solubility, product colour, flowability and compactness. Significant differences in the functional properties of pellets with varying bulk densities (loose and tapped) and macro-porosities (loose, tapped) were observed. The observed mean bulk density of biodegradable pellets made from different formulations ranged between 0.213 and 0.560 g/ml for loose fill conditions and 0.248 to 0.604 g/ml for tapped fill conditions. Biodegradable pellets bear a good compaction for both loose and tapped fill methods. The mean macro-porosity of biodegradable pellets ranged between 1.19 and 54.48 % for loose fill condition and 0.29 to 53.35 % for tapped fill condition. Hausner ratio (HR) for biodegradable pellets varied from 1.026 to 1.328, indicating a good flowability of biodegradable pellets. Pearson's correlation between engineering properties and functional properties of biodegradable pellets revealed that from engineering properties functional properties can be predicted.

  17. Can a Century Old Experiment Reveal Hidden Properties of Water?

    Directory of Open Access Journals (Sweden)

    Elmar C. Fuchs

    2010-08-01

    Full Text Available In 1893 Sir William Armstrong placed a cotton thread between two wine glasses filled with chemically pure water. After applying a high voltage, a watery connection formed, and after some time, the cotton thread was pulled into one of the glasses, leaving a rope of water suspended between the two glasses. Although being a very simple experiment, it is of special interest since it comprises a number of phenomena currently tackled in modern water science like electrolysis-less charge transport and nanobubbles. This work gives some background information about water research in general and describes the water bridge phenomenon from the viewpoint of different fields such as electrohydrodynamics and quantum field theory. It is shown that the investigation of the floating water bridge led to new discoveries about water, both in the macroscopic and microscopic realm – but these were merely “hidden” in that sense that they only become evident upon application of electric fields.

  18. Defect properties from X-ray scattering experiments

    International Nuclear Information System (INIS)

    Peisl, H.

    1976-01-01

    Lattice distortions due to defects in crystals can be studied most directly by elastic X-ray or neutron scattering experiments. The 'size' of the defects can be determined from the shift of the Bragg reflections. Defect induced diffuse scattering intensity close to and between Bragg reflections gives information on the strength and symmetry of the distortion fields and yields the atomic structure of point defects (interstitials, vacancies, small aggregates). Diffuse scattering is a very sensitive method to decide whether defects are present as isolated point defects or have formed aggregates. X-ray scattering has been used to study defects produced in various ionic crystals by γ- and neutron irradiation. After an introduction to the principles of the method the experimental results will be reviewed and discussed in some detail. (orig.) [de

  19. Gyrokinetic Simulation of Global Turbulent Transport Properties in Tokamak Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Wang, W.X.; Lin, Z.; Tang, W.M.; Lee, W.W.; Ethier, S.; Lewandowski, J.L.V.; Rewoldt, G.; Hahm, T.S.; Manickam, J.

    2006-01-01

    A general geometry gyro-kinetic model for particle simulation of plasma turbulence in tokamak experiments is described. It incorporates the comprehensive influence of noncircular cross section, realistic plasma profiles, plasma rotation, neoclassical (equilibrium) electric fields, and Coulomb collisions. An interesting result of global turbulence development in a shaped tokamak plasma is presented with regard to nonlinear turbulence spreading into the linearly stable region. The mutual interaction between turbulence and zonal flows in collisionless plasmas is studied with a focus on identifying possible nonlinear saturation mechanisms for zonal flows. A bursting temporal behavior with a period longer than the geodesic acoustic oscillation period is observed even in a collisionless system. Our simulation results suggest that the zonal flows can drive turbulence. However, this process is too weak to be an effective zonal flow saturation mechanism.

  20. Color film spectral properties test experiment for target simulation

    Science.gov (United States)

    Liu, Xinyue; Ming, Xing; Fan, Da; Guo, Wenji

    2017-04-01

    In hardware-in-loop test of the aviation spectra camera, the liquid crystal light valve and digital micro-mirror device could not simulate the spectrum characteristics of the landmark. A test system frame was provided based on the color film for testing the spectra camera; and the spectrum characteristics of the color film was test in the paper. The result of the experiment shows that difference was existed between the landmark and the film spectrum curse. However, the spectrum curse peak should change according to the color, and the curse is similar with the standard color traps. So, if the quantity value of error between the landmark and the film was calibrated and the error could be compensated, the film could be utilized in the hardware-in-loop test for the aviation spectra camera.

  1. The influence of past research on the design of experiments with dissolved organic matter and engineered nanoparticles.

    Directory of Open Access Journals (Sweden)

    Nicole Sani-Kast

    Full Text Available To assess the environmental fate of engineered nanoparticles (ENPs, it is essential to understand their interactions with dissolved organic matter (DOM. The highly complex nature of the interactions between DOM and ENPs and other particulate matter (PM requires investigating a wide range of material types under different conditions. However, despite repeated calls for an increased diversity of the DOM and PM studied, researchers increasingly focus on certain subsets of DOM and PM. Considering the discrepancy between the calls for more diversity and the research actually carried out, we hypothesize that materials that were studied more often are more visible in the scientific literature and therefore are more likely to be studied again. To investigate the plausibility of this hypothesis, we developed an agent-based model simulating the material choice in the experiments studying the interaction between DOM and PM between 1990 and 2015. The model reproduces the temporal trends in the choice of materials as well as the main properties of a network that displays the DOM and PM types investigated experimentally. The results, which support the hypothesis of a positive reinforcing material choice, help to explain why calls to increase the diversity of the materials studied are repeatedly made and why recent criticism states that the selection of materials is unbalanced.

  2. Preliminary Investigations of Some Engineering Properties for the Use of Different Soils in Waste Disposal Cover System

    International Nuclear Information System (INIS)

    Abdel Rahman, R.O.

    2008-01-01

    Near surface disposal facilities are designed to provide long term isolation for low and intermediate level radioactive wastes from the human environment by means of multi-barriers system, which consists of a combination of natural and engineering barriers that act passively to isolate the waste. Adequate and reliable multi-layer engineered cover system is required by the long-term safety concept for waste disposal to control moisture and percolation, promote surface water runoff, minimize erosion, and prevent direct exposure to the waste. In this work, investigations of some engineering properties that are utilized in hydrological and geotechnical design of capillary barrier have been estimated for different local soil textures. Measurements of the physical properties of the studied soil textures have been conducted to determine their suitability for the utilization in engineered cover system for near surface disposal facility. The soil water characteristics have been estimated from the measured physical properties using Vereeckens pedotransfer functions. The critical pressure head for different combinations of soils have been evaluated and the thickness of the finer layer has been calculated. Also some mechanical properties, angle of internal friction and the cohesion, have been estimated using pedotransfer function. The pre-compression stresses have been evaluated and the slope stability of the designed barriers has been quantified by comparing the factor of safety for each studied case for different slope values

  3. Influence of the temporal deposition of extracellular matrix on the mechanical properties of tissue-engineered cartilage

    NARCIS (Netherlands)

    Khoshgoftar, M.; Wilson, W.; Ito, K.; Donkelaar, van C.C.

    2014-01-01

    Enhancement of the load-bearing capacity of tissue engineered (TE) cartilage is expected to improve the clinical outcome of implantations. Generally, cartilage TE studies aim to increase the total extracellular matrix (ECM) content to improve implant mechanical properties. Besides the ECM content,

  4. Influence of tissue- and cell-scale extracellular matrix distribution on the mechanical properties of tissue-engineered cartilage

    NARCIS (Netherlands)

    Khoshgoftar, M.; Wilson, W.; Ito, K.; Donkelaar, C.C. van

    2013-01-01

    The insufficient load-bearing capacity of today's tissue- engineered (TE) cartilage limits its clinical application. Generally, cartilage TE studies aim to increase the extracellular matrix (ECM) content, as this is thought to determine the load-bearing properties of the cartilage. However, there

  5. Influence of tissue- and cell-scale extracellular matrix distribution on the mechanical properties of tissue engineered cartilage

    NARCIS (Netherlands)

    Khoshgoftar, M.; Wilson, W.; Ito, K.; Donkelaar, van C.C.

    2013-01-01

    The insufficient load-bearing capacity of today’s tissue- engineered (TE) cartilage limits its clinical application. Generally, cartilage TE studies aim to increase the extracellular matrix (ECM) content, as this is thought to determine the load-bearing properties of the cartilage. However, there

  6. Transport properties of olivine grain boundaries from electrical conductivity experiments

    Science.gov (United States)

    Pommier, Anne; Kohlstedt, David L.; Hansen, Lars N.; Mackwell, Stephen; Tasaka, Miki; Heidelbach, Florian; Leinenweber, Kurt

    2018-05-01

    Grain boundary processes contribute significantly to electronic and ionic transports in materials within Earth's interior. We report a novel experimental study of grain boundary conductivity in highly strained olivine aggregates that demonstrates the importance of misorientation angle between adjacent grains on aggregate transport properties. We performed electrical conductivity measurements of melt-free polycrystalline olivine (Fo90) samples that had been previously deformed at 1200 °C and 0.3 GPa to shear strains up to γ = 7.3. The electrical conductivity and anisotropy were measured at 2.8 GPa over the temperature range 700-1400 °C. We observed that (1) the electrical conductivity of samples with a small grain size (3-6 µm) and strong crystallographic preferred orientation produced by dynamic recrystallization during large-strain shear deformation is a factor of 10 or more larger than that measured on coarse-grained samples, (2) the sample deformed to the highest strain is the most conductive even though it does not have the smallest grain size, and (3) conductivity is up to a factor of 4 larger in the direction of shear than normal to the shear plane. Based on these results combined with electrical conductivity data for coarse-grained, polycrystalline olivine and for single crystals, we propose that the electrical conductivity of our fine-grained samples is dominated by grain boundary paths. In addition, the electrical anisotropy results from preferential alignment of higher-conductivity grain boundaries associated with the development of a strong crystallographic preferred orientation of the grains.

  7. Low Immunogenic Endothelial Cells Maintain Morphological and Functional Properties Required for Vascular Tissue Engineering.

    Science.gov (United States)

    Lau, Skadi; Eicke, Dorothee; Carvalho Oliveira, Marco; Wiegmann, Bettina; Schrimpf, Claudia; Haverich, Axel; Blasczyk, Rainer; Wilhelmi, Mathias; Figueiredo, Constança; Böer, Ulrike

    2018-03-01

    functional properties required for vascular tissue engineering. This extends the spectrum of available cell sources from autologous to allogeneic sources, thereby accelerating the generation of tissue-engineered vascular grafts in acute clinical cases.

  8. Summary of facility and operating experience on helium engineering demonstration loop (HENDEL)

    Energy Technology Data Exchange (ETDEWEB)

    Ouchi, Yoshihiro; Fujisaki, Katsuo; Kobayashi, Toshiaki; Kato, Michio; Ota, Yukimaru; Watanabe, Syuji; Kobayashi, Hideki; Mogi, Haruyoshi [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

    1996-07-01

    The HENDEL is a test facility to perform full scale demonstration tests on the core internals and high temperature components for the High Temperature Engineering Test Reactor(HTTR). The main systems consist of Mother(M) and Adapter(A), fuel stack Test(T{sub 1}) and in-core structure Test(T{sub 2}) sections. The (M+A) section can supply high temperature helium gas to the test section. The M+A section completed in March 1982 has been operated for about 22900 hours till February 1995. The T{sub 1} and T{sub 2} sections, completed in March 1983 and June 1986, have been operated for about 19400 and 16700 hours, respectively. In this period, a large number of tests have been conducted to verify the performance and safety features of the HTTR components. The results obtained from these tests have been effectively applied to the detailed design, licensing procedures and construction of the HTTR. The operating experience of the HENDEL for more than 10 years also brought us establishment of the technique of operation of a large scale helium gas loop, handling of helium gas and maintenance of high temperature facilities. The technique will be available for the operation of the HTTR. This paper mainly describes the summary of plant facirities, operating experience and maintenance on the HENDEL. (author)

  9. A new experience: the course of ethics in engineering in the Department of Civil Engineering, University of Granada.

    Science.gov (United States)

    Gil-Martín, Luisa María; Hernández-Montes, Enrique; Segura-Naya, Armando

    2010-06-01

    A course in professional ethics for civil engineers was taught for the first time in Spain during the academic year 2007/08. In this paper a survey on the satisfaction and expectation of the course is presented. Surprisingly the students sought moral and ethical principles for their own ordinary lives as well as for their profession. Students were concerned about the law, but in their actions they were more concerned with their conscience, aware that it can be separate from the law.

  10. Additive Manufacturing, Design, Testing, and Fabrication: A Full Engineering Experience at JSC

    Science.gov (United States)

    Zusack, Steven

    2016-01-01

    I worked on several projects this term. While most projects involved additive manufacturing, I was also involved with two design projects, two testing projects, and a fabrication project. The primary mentor for these was Richard Hagen. Secondary mentors were Hai Nguyen, Khadijah Shariff, and fabrication training from James Brown. Overall, my experience at JSC has been successful and what I have learned will continue to help me in my engineering education and profession long after I leave. My 3D printing projects ranged from less than a 1 cubic centimeter to about 1 cubic foot and involved several printers using different printing technologies. It was exciting to become familiar with printing technologies such as industrial grade FDM (Fused Deposition Modeling), the relatively new SLA (Stereolithography), and PolyJet. My primary duty with the FDM printers was to model parts that came in from various sources to print effectively and efficiently. Using methods my mentor taught me and the Stratasys Insight software, I was able to minimize imperfections, hasten build time, improve strength for specific forces (tensile, shear, etc...), and reduce likelihood of a print-failure. Also using FDM, I learned how to repair a part after it was printed. This is done by using a special kind of glue that chemically melts the two faces of plastic parts together to form a fused interface. My first goal with SLA technology was to bring the printer back to operational readiness. In becoming familiar with the Pegasus SLA printer, I researched the leveling, laser settings, and different vats to hold liquid material. With this research, I was successfully able to bring the Pegasus back online and have successfully printed multiple sample parts as well as functional parts. My experience with PolyJet technology has been focused on an understanding of the abilities/limits, costs, and the maintenance for daily use. Still upcoming will be experience with using a composite printer that uses FDM

  11. Experiences of African American Young Women in Science, Technology, Engineering, and Mathematics (STEM) Education

    Science.gov (United States)

    Kolo, Yovonda Ingram

    African American women are underrepresented in science, technology, engineering, and mathematics (STEM) fields throughout the United States. As the need for STEM professionals in the United States increases, it is important to ensure that African American women are among those professionals making valuable contributions to society. The purpose of this phenomenological study was to describe the experiences of African American young women in relation to STEM education. The research question for this study examined how experiences with STEM in K-10 education influenced African American young women's academic choices in their final years in high school. The theory of multicontextuality was used to provide the conceptual framework. The primary data source was interviews. The sample was composed of 11 African American young women in their junior or senior year in high school. Data were analyzed through the process of open coding, categorizing, and identifying emerging themes. Ten themes emerged from the answers to research questions. The themes were (a) high teacher expectations, (b) participation in extra-curricular activities, (c) engagement in group-work, (d) learning from lectures, (e) strong parental involvement, (f) helping others, (g) self-efficacy, (h) gender empowerment, (i) race empowerment, and (j) strategic recruitment practices. This study may lead to positive social change by adding to the understanding of the experiences of African American young women in STEM. By doing so, these findings might motivate other African American young women to pursue advanced STEM classes. These findings may also provide guidance to parents and educators to help increase the number of African American women in STEM.

  12. Enhanced mechanical properties of thermosensitive chitosan hydrogel by silk fibers for cartilage tissue engineering

    International Nuclear Information System (INIS)

    Mirahmadi, Fereshteh; Tafazzoli-Shadpour, Mohammad; Shokrgozar, Mohammad Ali; Bonakdar, Shahin

    2013-01-01

    Articular cartilage has limited repair capability following traumatic injuries and current methods of treatment remain inefficient. Reconstructing cartilage provides a new way for cartilage repair and natural polymers are often used as scaffold because of their biocompatibility and biofunctionality. In this study, we added degummed chopped silk fibers and electrospun silk fibers to the thermosensitive chitosan/glycerophosphate hydrogels to reinforce two hydrogel constructs which were used as scaffold for hyaline cartilage regeneration. The gelation temperature and gelation time of hydrogel were analyzed by the rheometer and vial tilting method. Mechanical characterization was measured by uniaxial compression, indentation and dynamic mechanical analysis assay. Chondrocytes were then harvested from the knee joint of the New Zealand white rabbits and cultured in constructs. The cell proliferation, viability, production of glycosaminoglycans and collagen type II were assessed. The results showed that mechanical properties of the hydrogel were significantly enhanced when a hybrid with two layers of electrospun silk fibers was made. The results of GAG and collagen type II in cell-seeded scaffolds indicate support of the chondrogenic phenotype for chondrocytes with a significant increase in degummed silk fiber–hydrogel composite for GAG content and in two-layer electrospun fiber–hydrogel composite for Col II. It was concluded that these two modified scaffolds could be employed for cartilage tissue engineering. - Highlights: • Chitosan hydrogel composites fabricated by two forms of silk fiber • Silk fibers provide structural support for the hydrogel matrix. • The mechanical properties of hydrogel significantly improved by associating with silk. • Production of GAG and collagen type II was demonstrated within the scaffolds

  13. Enhanced mechanical properties of thermosensitive chitosan hydrogel by silk fibers for cartilage tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Mirahmadi, Fereshteh [Faculty of Biomedical Engineering, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); National Cell Bank of Iran, Pasteur Institute of Iran, Tehran (Iran, Islamic Republic of); Tafazzoli-Shadpour, Mohammad, E-mail: Tafazoli@aut.ac.ir [Faculty of Biomedical Engineering, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Shokrgozar, Mohammad Ali, E-mail: mashokrgozar@pasteur.ac.ir [National Cell Bank of Iran, Pasteur Institute of Iran, Tehran (Iran, Islamic Republic of); Bonakdar, Shahin [National Cell Bank of Iran, Pasteur Institute of Iran, Tehran (Iran, Islamic Republic of)

    2013-12-01

    Articular cartilage has limited repair capability following traumatic injuries and current methods of treatment remain inefficient. Reconstructing cartilage provides a new way for cartilage repair and natural polymers are often used as scaffold because of their biocompatibility and biofunctionality. In this study, we added degummed chopped silk fibers and electrospun silk fibers to the thermosensitive chitosan/glycerophosphate hydrogels to reinforce two hydrogel constructs which were used as scaffold for hyaline cartilage regeneration. The gelation temperature and gelation time of hydrogel were analyzed by the rheometer and vial tilting method. Mechanical characterization was measured by uniaxial compression, indentation and dynamic mechanical analysis assay. Chondrocytes were then harvested from the knee joint of the New Zealand white rabbits and cultured in constructs. The cell proliferation, viability, production of glycosaminoglycans and collagen type II were assessed. The results showed that mechanical properties of the hydrogel were significantly enhanced when a hybrid with two layers of electrospun silk fibers was made. The results of GAG and collagen type II in cell-seeded scaffolds indicate support of the chondrogenic phenotype for chondrocytes with a significant increase in degummed silk fiber–hydrogel composite for GAG content and in two-layer electrospun fiber–hydrogel composite for Col II. It was concluded that these two modified scaffolds could be employed for cartilage tissue engineering. - Highlights: • Chitosan hydrogel composites fabricated by two forms of silk fiber • Silk fibers provide structural support for the hydrogel matrix. • The mechanical properties of hydrogel significantly improved by associating with silk. • Production of GAG and collagen type II was demonstrated within the scaffolds.

  14. Project Based Learning experiences in the space engineering education at Technical University of Madrid

    Science.gov (United States)

    Rodríguez, Jacobo; Laverón-Simavilla, Ana; del Cura, Juan M.; Ezquerro, José M.; Lapuerta, Victoria; Cordero-Gracia, Marta

    2015-10-01

    This work describes the innovation activities performed in the field of space education since the academic year 2009/10 at the Technical University of Madrid (UPM), in collaboration with the Spanish User Support and Operations Center (E-USOC), the center assigned by the European Space Agency (ESA) in Spain to support the operations of scientific experiments on board the International Space Station. These activities have been integrated within the last year of the UPM Aerospace Engineering degree. A laboratory has been created, where students have to validate and integrate the subsystems of a microsatellite using demonstrator satellites. In parallel, the students participate in a Project Based Learning (PBL) training process in which they work in groups to develop the conceptual design of a space mission. One student in each group takes the role of project manager, another one is responsible for the mission design and the rest are each responsible for the design of one of the satellite subsystems. A ground station has also been set up with the help of students developing their final thesis, which will allow future students to perform training sessions and learn how to communicate with satellites, how to receive telemetry and how to process the data. Several surveys have been conducted along two academic years to evaluate the impact of these techniques in engineering learning. The surveys evaluate the acquisition of specific and generic competences, as well as the students' degree of satisfaction with respect to the use of these learning methodologies. The results of the surveys and the perception of the lecturers show that PBL encourages students' motivation and improves their results. They not only acquire better technical training, but also improve their transversal skills. It is also pointed out that this methodology requires more dedication from lecturers than traditional methods.

  15. A divide and conquer approach to determine the Pareto frontier for optimization of protein engineering experiments

    Science.gov (United States)

    He, Lu; Friedman, Alan M.; Bailey-Kellogg, Chris

    2016-01-01

    In developing improved protein variants by site-directed mutagenesis or recombination, there are often competing objectives that must be considered in designing an experiment (selecting mutations or breakpoints): stability vs. novelty, affinity vs. specificity, activity vs. immunogenicity, and so forth. Pareto optimal experimental designs make the best trade-offs between competing objectives. Such designs are not “dominated”; i.e., no other design is better than a Pareto optimal design for one objective without being worse for another objective. Our goal is to produce all the Pareto optimal designs (the Pareto frontier), in order to characterize the trade-offs and suggest designs most worth considering, but to avoid explicitly considering the large number of dominated designs. To do so, we develop a divide-and-conquer algorithm, PEPFR (Protein Engineering Pareto FRontier), that hierarchically subdivides the objective space, employing appropriate dynamic programming or integer programming methods to optimize designs in different regions. This divide-and-conquer approach is efficient in that the number of divisions (and thus calls to the optimizer) is directly proportional to the number of Pareto optimal designs. We demonstrate PEPFR with three protein engineering case studies: site-directed recombination for stability and diversity via dynamic programming, site-directed mutagenesis of interacting proteins for affinity and specificity via integer programming, and site-directed mutagenesis of a therapeutic protein for activity and immunogenicity via integer programming. We show that PEPFR is able to effectively produce all the Pareto optimal designs, discovering many more designs than previous methods. The characterization of the Pareto frontier provides additional insights into the local stability of design choices as well as global trends leading to trade-offs between competing criteria. PMID:22180081

  16. Preparing University Students to Lead K-12 Engineering Outreach Programmes: A Design Experiment

    Science.gov (United States)

    Anthony, Anika B.; Greene, Howard; Post, Paul E.; Parkhurst, Andrew; Zhan, Xi

    2016-01-01

    This paper describes an engineering outreach programme designed to increase the interest of under-represented youth in engineering and to disseminate pre-engineering design challenge materials to K-12 educators and volunteers. Given university students' critical role as facilitators of the outreach programme, researchers conducted a two-year…

  17. Building a Framework for Engineering Design Experiences in STEM: A Synthesis

    Science.gov (United States)

    Denson, Cameron D.

    2011-01-01

    Since the inception of the National Center for Engineering and Technology Education in 2004, educators and researchers have struggled to identify the necessary components of a "good" engineering design challenge for high school students. In reading and analyzing the position papers on engineering design many themes emerged that may begin to form a…

  18. Entrepreneurship in the Engineering Curriculum: Some Initial Results of PUC-Rio's Experiment.

    Science.gov (United States)

    Aranha, Jose Alberto S.; Pimenta-Bueno, J. A.; Scavarda do Carmo, Luiz Carlos; da Silveira, Marcos A.

    The ideal of the entrepreneurial spirit has played a key role in shaping the current reform of engineering education at the Pontificia Universidade Catolica do Rio de Janeiro (PUC-Rio). The previous paradigm of a science-based conceptual engineer has given place to what may be termed a science-based entrepreneurial engineer. This paper discusses…

  19. Analysis of 3D Printed Diopside Scaffolds Properties for Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Tingting LIU

    2015-11-01

    Full Text Available Diopside exhibits favorable potential for bone repair on account of the good mechanical performance, bioactivity and biocompatibility. In this paper, diopside scaffolds with high pore interconnectivity were successfully fabricated by laser three-dimensional (3D printing. The microstructure and mechanical performance of the diopside scaffolds were studied. The experimental analysis indicated that diopside particles gradually fused together until a dense structure was built with an energy density increasing in the range between 2.4 and 4.8 J·mm-2. Meanwhile, compressive strength and fracture toughness increased gradually from 5.96 ± 0.88 MPa to 10.87 ± 0.55 MPa. However, mechanical properties decreased due to the appearance of voids when energy density were 5.4 and 6 J·mm-2. Simulated body fluid (SBF tests showed that apatite crystals formed on the diopside scaffolds surface, and the apatite crystals increased with soaking time. Cell culture tests indicated the scaffolds supported the adhesion and growth of MG-63 cells. The study suggested that diopside scaffolds fabricated by laser 3D printing are promising candidates for bone tissue engineering.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9845

  20. Secondary materials: Engineering properties, environmental consequences, and social and economic impacts. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Breslin, V.; Reaven, S.; Schwartz, M.; Swanson, L.; Zweig, M.; Bortman, M.; Schubel, J.

    1993-08-01

    This report investigates two secondary materials, plastic lumber made from mixed plastic waste, and cement blocks and structures made with incinerator ash. Engineering properties, environmental impacts, and energy costs and savings of these secondary materials are compared to standard lumber products and cement blocks. Market capacity and social acceptance of plastic lumber and stabilized ash products are analyzed. These secondary materials apparently have potential markets; however, their economic value is primarily that they will not take up landfill space. For plastic lumber and stabilized incinerator ash products, marine and highway construction seem ideal public works applications. Incinerator ash may be suitable to use in seawalls, jetties, fishing reefs, highway barriers, and roadbed applications. Docks, piers, highway sound barriers, parking stops, and park furniture may all be made from plastic lumber. To encourage public acceptance and improve the market potential of secondary materials, these activities could be beneficial: industry should emphasize developing useful, long-lived products; industry and governments should create product performance criteria; government should provide rigorous testing and demonstration programs; and government and industry should cooperate to improve public outreach and educational programs.

  1. Mechanical properties of electrospun bilayer fibrous membranes as potential scaffolds for tissue engineering.

    Science.gov (United States)

    Pu, Juan; Komvopoulos, Kyriakos

    2014-06-01

    Bilayer fibrous membranes of poly(l-lactic acid) (PLLA) were fabricated by electrospinning, using a parallel-disk mandrel configuration that resulted in the sequential deposition of a layer with fibers aligned across the two parallel disks and a layer with randomly oriented fibers, both layers deposited in a single process step. Membrane structure and fiber alignment were characterized by scanning electron microscopy and two-dimensional fast Fourier transform. Because of the intricacies of the generated electric field, bilayer membranes exhibited higher porosity than single-layer membranes consisting of randomly oriented fibers fabricated with a solid-drum collector. However, despite their higher porosity, bilayer membranes demonstrated generally higher elastic modulus, yield strength and toughness than single-layer membranes with random fibers. Bilayer membrane deformation at relatively high strain rates comprised multiple abrupt microfracture events characterized by discontinuous fiber breakage. Bilayer membrane elongation yielded excessive necking of the layer with random fibers and remarkable fiber stretching (on the order of 400%) in the layer with fibers aligned in the stress direction. In addition, fibers in both layers exhibited multiple localized necking, attributed to the nonuniform distribution of crystalline phases in the fibrillar structure. The high membrane porosity, good mechanical properties, and good biocompatibility and biodegradability of PLLA (demonstrated in previous studies) make the present bilayer membranes good scaffold candidates for a wide range of tissue engineering applications. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  2. Mechanical properties and biocompatibility of porous titanium scaffolds for bone tissue engineering.

    Science.gov (United States)

    Chen, Yunhui; Frith, Jessica Ellen; Dehghan-Manshadi, Ali; Attar, Hooyar; Kent, Damon; Soro, Nicolas Dominique Mathieu; Bermingham, Michael J; Dargusch, Matthew S

    2017-11-01

    Synthetic scaffolds are a highly promising new approach to replace both autografts and allografts to repair and remodel damaged bone tissue. Biocompatible porous titanium scaffold was manufactured through a powder metallurgy approach. Magnesium powder was used as space holder material which was compacted with titanium powder and removed during sintering. Evaluation of the porosity and mechanical properties showed a high level of compatibility with human cortical bone. Interconnectivity between pores is higher than 95% for porosity as low as 30%. The elastic moduli are 44.2GPa, 24.7GPa and 15.4GPa for 30%, 40% and 50% porosity samples which match well to that of natural bone (4-30GPa). The yield strengths for 30% and 40% porosity samples of 221.7MPa and 117MPa are superior to that of human cortical bone (130-180MPa). In-vitro cell culture tests on the scaffold samples using Human Mesenchymal Stem Cells (hMSCs) demonstrated their biocompatibility and indicated osseointegration potential. The scaffolds allowed cells to adhere and spread both on the surface and inside the pore structures. With increasing levels of porosity/interconnectivity, improved cell proliferation is obtained within the pores. It is concluded that samples with 30% porosity exhibit the best biocompatibility. The results suggest that porous titanium scaffolds generated using this manufacturing route have excellent potential for hard tissue engineering applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Enhanced mechanical properties of thermosensitive chitosan hydrogel by silk fibers for cartilage tissue engineering.

    Science.gov (United States)

    Mirahmadi, Fereshteh; Tafazzoli-Shadpour, Mohammad; Shokrgozar, Mohammad Ali; Bonakdar, Shahin

    2013-12-01

    Articular cartilage has limited repair capability following traumatic injuries and current methods of treatment remain inefficient. Reconstructing cartilage provides a new way for cartilage repair and natural polymers are often used as scaffold because of their biocompatibility and biofunctionality. In this study, we added degummed chopped silk fibers and electrospun silk fibers to the thermosensitive chitosan/glycerophosphate hydrogels to reinforce two hydrogel constructs which were used as scaffold for hyaline cartilage regeneration. The gelation temperature and gelation time of hydrogel were analyzed by the rheometer and vial tilting method. Mechanical characterization was measured by uniaxial compression, indentation and dynamic mechanical analysis assay. Chondrocytes were then harvested from the knee joint of the New Zealand white rabbits and cultured in constructs. The cell proliferation, viability, production of glycosaminoglycans and collagen type II were assessed. The results showed that mechanical properties of the hydrogel were significantly enhanced when a hybrid with two layers of electrospun silk fibers was made. The results of GAG and collagen type II in cell-seeded scaffolds indicate support of the chondrogenic phenotype for chondrocytes with a significant increase in degummed silk fiber-hydrogel composite for GAG content and in two-layer electrospun fiber-hydrogel composite for Col II. It was concluded that these two modified scaffolds could be employed for cartilage tissue engineering. © 2013.

  4. Development of the mechanical properties of engineered skin substitutes after grafting to full-thickness wounds.

    Science.gov (United States)

    Sander, Edward A; Lynch, Kaari A; Boyce, Steven T

    2014-05-01

    Engineered skin substitutes (ESSs) have been reported to close full-thickness burn wounds but are subject to loss from mechanical shear due to their deficiencies in tensile strength and elasticity. Hypothetically, if the mechanical properties of ESS matched those of native skin, losses due to shear or fracture could be reduced. To consider modifications of the composition of ESS to improve homology with native skin, biomechanical analyses of the current composition of ESS were performed. ESSs consist of a degradable biopolymer scaffold of type I collagen and chondroitin-sulfate (CGS) that is populated sequentially with cultured human dermal fibroblasts (hF) and epidermal keratinocytes (hK). In the current study, the hydrated biopolymer scaffold (CGS), the scaffold populated with hF dermal skin substitute (DSS), or the complete ESS were evaluated mechanically for linear stiffness (N/mm), ultimate tensile load at failure (N), maximum extension at failure (mm), and energy absorbed up to the point of failure (N-mm). These biomechanical end points were also used to evaluate ESS at six weeks after grafting to full-thickness skin wounds in athymic mice and compared to murine autograft or excised murine skin. The data showed statistically significant differences (p clinical morbidity from graft loss.

  5. Tailoring the properties of europium-doped potassium calcium iodide scintillators through defect engineering

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yuntao; Rutstrom, Daniel J.; Zhuravleva, Mariya; Loyd, Matthew [Scintillation Materials Research Center, University of Tennessee, Knoxville, TN (United States); Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN (United States); Li, Qi [Physical Science Division, IBM Thomas J Watson Research Center, Yorktown Heights, NY (United States); Department of Computer Science, University of Illinois, Urbana-Champaign, IL (United States); Stand, Luis [Scintillation Materials Research Center, University of Tennessee, Knoxville, TN (United States); Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN (United States); Bredesen Center for Interdisciplinary Research and Graduate Education, University of Tennessee, Knoxville, TN (United States); Koschan, Merry [Scintillation Materials Research Center, University of Tennessee, Knoxville, TN (United States); Melcher, Charles L. [Scintillation Materials Research Center, University of Tennessee, Knoxville, TN (United States); Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN (United States); Bredesen Center for Interdisciplinary Research and Graduate Education, University of Tennessee, Knoxville, TN (United States); Departments of Nuclear Engineering, University of Tennessee, Knoxville, TN (United States)

    2018-02-15

    Codoping is an effective approach for precise control of point defects in many advanced materials, and can be used to optimize their function. This paper reports an effort toward tailoring the scintillation properties of metal halides through defect engineering. A study of aliovalent codoping of the KCaI{sub 3}:Eu{sup 2+} single-crystalline scintillators is performed, through which it is discovered that a simultaneous suppression of X-ray induced afterglow and improvement of gamma-ray energy resolution can be successfully achieved via Zr{sup 4+} codoping. The afterglow level is reduced by more than twofold with Zr{sup 4+} codoping. The energy resolution of a 5 mm cubic KCaI{sub 3}:Eu{sup 2+} sample is improved from 3.25 to 2.7% at 662 keV, and 6.5 to 5.73% at 122 keV upon Zr{sup 4+} codoping. Physical explanations for the improvements are revealed from our investigations into both the electronic structure and thermodynamics of the defects by using thermoluminescence techniques and density functional theory calculations. The codoped Zr{sup 4+} ions prefer to form interstitials acting as shallow electron traps. The {Zr_C_a+V_C_a} complex can co-exist with Zr{sub i} interstitials as shallow hole traps under certain condition, which are able to trap holes temporarily. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. EXPERIENCE AND PROSPECTS OF MASTER’S DEGREE TRAINING OF ENGINEERING STAFF IN THE FIELD OF METALLURGICAL SCIENCE

    Directory of Open Access Journals (Sweden)

    V. M. Konstantinov

    2016-01-01

    Full Text Available The experience of training for MBA in engineering and technologies for specialties “Materials Science in Mechanical Engineering” at the department was analyzed. Efficiency of the practical-focused Master’s degree program for engineering staff of the machine-building and metallurgical enterprises was emphasized. Some ways to increase efficiency of master training of engineering experts in the field of metallurgical science and heat treatment are offered. Need of more active interaction with engineering services of the production enterprise during implementation of the master thesis was proved. Need of domination of requirements of the production enterprise is highlighted in master preparation program. The algorithm of interaction of department and technical service of the production enterprise during training of the factory expert in the correspondence practical-focused Master’s degree program is offered.

  7. Investigation of the Impact of Fuel Properties on Particulate Number Emission of a Modern Gasoline Direct Injection Engine

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, Robert L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Fioroni, Gina [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Fatouraie, Mohammad [Robert Bosch LLC; Frommherz, Mario [Robert Bosch LLC; Mosburger, Michael [Robert Bosch LLC; Chapman, Elana [General Motors LLC; Li, Sharon [General Motors LLC

    2018-04-03

    Gasoline Direct Injection (GDI) has become the preferred technology for spark-ignition engines resulting in greater specific power output and lower fuel consumption, and consequently reduction in CO2 emission. However, GDI engines face a substantial challenge in meeting new and future emission limits, especially the stringent particle number (PN) emissions recently introduced in Europe and China. Studies have shown that the fuel used by a vehicle has a significant impact on engine out emissions. In this study, nine fuels with varying chemical composition and physical properties were tested on a modern turbo-charged side-mounted GDI engine with design changes to reduce particulate emissions. The fuels tested included four fuels meeting US certification requirements; two fuels meeting European certification requirements; and one fuel meeting China 6 certification requirements being proposed at the time of this work. Two risk safeguard fuels (RSG), representing the properties of worst case market fuels in Europe and China, were also included. The particle number concentration of the solid particulates was measured in the engine-out exhaust flow at steady state engine operations with load and speed sweeps, and semi-transient load steps. The test results showed a factor of 6 PN emission difference among all certification fuels tested. Combined with detailed fuel analyses, this study evaluated important factors (such as oxygenates, carbon chain length and thermo-physical properties) that cause PN emissions which were not included in PMI index. A linear regression was performed to develop a PN predictive model which showed improved fitting quality than using PMI.

  8. A chondroitinase-ABC and TGF-β1 treatment regimen for enhancing the mechanical properties of tissue engineered fibrocartilage

    Science.gov (United States)

    MacBarb, Regina F.; Makris, Eleftherios A.; Hu, Jerry C.; Athanasiou, Kyriacos A.

    2012-01-01

    The development of functionally equivalent fibrocartilage remains elusive despite efforts to engineer tissues such as the knee menisci, intervertebral disc, and TMJ disc. Attempts to engineer these structures often fail to create tissues with mechanical properties on par with native tissue, resulting in constructs unsuitable for clinical applications. The objective of this study was to engineer a spectrum of biomimetic fibrocartilages representative of the distinct functional properties found in native tissues. Using the self-assembly process, different co-cultures of meniscus cells (MCs) and articular chondrocytes (ACs) were seeded into agarose wells and treated with the catabolic agent chondroitinase-ABC (C-ABC) and the anabolic agent transforming growth factor-β1 (TGF-β1) via a two-factor (cell ratio and bioactive treatment), full factorial study design. Application of both C-ABC and TGF-β1 resulted in a beneficial or positive increase in the collagen content of treated constructs compared to controls. Significant increases in both the collagen density and fiber diameter were also seen with this treatment, increasing these values 32% and 15%, respectively, over control values. Mechanical testing found the combined bioactive treatment to synergistically increase the Young’s modulus and ultimate tensile strength of the engineered fibrocartilages compared to controls, with values reaching the lower spectrum of those found in native tissues. Together, these data demonstrate that C-ABC and TGF-β1 interact to develop a denser collagen matrix better able to withstand tensile loading. This study highlights a way to optimize the tensile properties of engineered fibrocartilage using a biochemical and biophysical agent together to create distinct fibrocartilages with functional properties mimicking those of native tissue. PMID:23041782

  9. How do Millennial Engineering and Technology Students Experience Learning Through Traditional Teaching Methods Employed in the University Setting?

    OpenAIRE

    Howard, Elizabeth A

    2011-01-01

    The purpose of the study was to document and analyze how Millennial engineering and technology students experience learning in large lecture classrooms. To help achieve this purpose, perceptions Millennials have toward traditional teaching methods employed in large lecture classes were analyzed and discussed. Additionally, this study documented how Millennials experienced technology within large lecture classrooms. A learning model depicting how Millennials experience learning within the larg...

  10. Current status of gas migration and swelling experiments using engineering scale model for immediate depth disposal in Japan

    International Nuclear Information System (INIS)

    Higashihara, Tomohiro; Ono, Makoto; Kawaragi, Chie; Saito, Shigeyuki

    2010-01-01

    In intermediate depth disposal facility of radioactive waste in Japan, waste is surrounded with bentonite layer to retard interaction of the waste and groundwater, because the bentonite layer saturated with the groundwater has very low hydraulic conductivity. On the other hand, it is important to confirm stability of barrier system for stress generated together with swelling of the bentonite and to understand effect of increase of gas pressure because of generation of hydrogen gas by corrosion of metallic waste. To understand and evaluate the swelling behavior of the bentonite layer, JNES carries out the experiment. In the experiments, we carry out the swelling experiment to examine the swelling behavior of the bentonite layer and the gas migration experiment to understand the gas migration behavior in the bentonite layer, using engineering scale model of the disposal facility. The swelling experiment has been in operation since June 2010. After this experiment, the gas migration experiment will start in July 2011. (orig.)

  11. Interdisciplinary Team-Teaching Experience for a Computer and Nuclear Energy Course for Electrical and Computer Engineering Students

    Science.gov (United States)

    Kim, Charles; Jackson, Deborah; Keiller, Peter

    2016-01-01

    A new, interdisciplinary, team-taught course has been designed to educate students in Electrical and Computer Engineering (ECE) so that they can respond to global and urgent issues concerning computer control systems in nuclear power plants. This paper discusses our experience and assessment of the interdisciplinary computer and nuclear energy…

  12. Effect of Inhomogeneous Mixture Properties on CI Combustion in a Schnurle-Type Gasoline DI Engine

    Science.gov (United States)

    Kim, Seok-Woo; Moriyoshi, Yasuo

    The authors have performed experiments on compression-ignition (CI) for a single-cylinder Schnurle-type two-stroke gasoline direct injection (DI) engine which employs a variable exhaust port, area, and deduced two presumptions from the experimental results. Firstly, the spatial distributions of fuel concentration and in-cylinder gas temperature are indispensable to enable CI operation under stratified charge conditions, because CI operation is not possible in a DI system although the necessary conditions of the scavenging efficiency and the in-cylinder gas temperature for the initiation of CI in homogeneous charge conditions are satisfied. Secondly, it is possible that flame propagation occurs in stratified charge CI conditions, because the combustion period in the later stage after 80% mass burned becomes longer than that with homogeneous charge CI combustion. In this report, in order to verify the above two presumptions deduced from experiments, the gas exchange process and mixture formation process were numerically analyzed, and the initiation conditions of CI were estimated using a CHEMKIN application. As a result, in case of CI with a late injection timing in DI system, it was found that CI was possible because high temperature but no fuel region and low temperature but rich fuel region exist in the cylinder due to inhomogeneous spatial distributions of fuel and temperature. Also, in case of CI with a late injection timing, the flame propagation was possible in the low-temperature and diluted rich region. Thereby, the two presumptions deduced from the experimental results were validated from the numerical analysis results.

  13. Manipulation of Optoelectronic Properties and Band Structure Engineering of Ultrathin Te Nanowires by Chemical Adsorption.

    Science.gov (United States)

    Roy, Ahin; Amin, Kazi Rafsanjani; Tripathi, Shalini; Biswas, Sangram; Singh, Abhishek K; Bid, Aveek; Ravishankar, N

    2017-06-14

    Band structure engineering is a powerful technique both for the design of new semiconductor materials and for imparting new functionalities to existing ones. In this article, we present a novel and versatile technique to achieve this by surface adsorption on low dimensional systems. As a specific example, we demonstrate, through detailed experiments and ab initio simulations, the controlled modification of band structure in ultrathin Te nanowires due to NO 2 adsorption. Measurements of the temperature dependence of resistivity of single ultrathin Te nanowire field-effect transistor (FET) devices exposed to increasing amounts of NO 2 reveal a gradual transition from a semiconducting to a metallic state. Gradual quenching of vibrational Raman modes of Te with increasing concentration of NO 2 supports the appearance of a metallic state in NO 2 adsorbed Te. Ab initio simulations attribute these observations to the appearance of midgap states in NO 2 adsorbed Te nanowires. Our results provide fundamental insights into the effects of ambient on the electronic structures of low-dimensional materials and can be exploited for designing novel chemical sensors.

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

    Science.gov (United States)

    Decaris, Martin L; Leach, J Kent

    2011-04-01

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

  15. U.S. Army Corps of Engineers Waste Experiences: More Than You May Think

    International Nuclear Information System (INIS)

    Hays, D. C.; Honerlah, H. B.

    2003-01-01

    U.S. Army Corps of Engineers (USACE) works with other federal, and state agencies through several different programs on numerous Hazardous, Toxic, and Radioactive Waste (HTRW) sites. Formerly Utilized Sites Remediation Program (FUSRAP), Formerly Used Defense Sites (FUDS), EPA Superfund, Installation Restoration, Army Deactivated Nuclear Reactor Program, and many other programs present hazardous, radioactive, and mixed waste issues. While the USACE has a reputation of excellent dirt movers, little is discussed of our other waste management experiences. This paper discusses some of the challenges facing the Health Physics (HP) staff of the USACE. The HP staff is currently organized as one team, the Radiation Safety Support Team (RSST), comprised of 15 individuals at 6 locations across the country. With typical RSST missions including HP consultation to USACE activities world wide, many waste challenges arise. These challenges have involved radioactive wastes of all classifications and stability. Sealed and unsealed sources; instruments and dials; contaminated earth and debris; liquids; lab, reactor, and medical wastes are all successfully managed by the USACE. USACE also develops, evaluates, and utilizes waste treatment Types of radioactive waste at HTRW sites include: Low Level Radioactive Wastes (LLRW) (class A, B, C, and greater than C), 11e.(2), Transuranic (TRU), Mixed, and Naturally Occurring (NORM/TENORM)

  16. The experience of work circumstances and stress; a profile of flight engineers in a labour dispute

    Directory of Open Access Journals (Sweden)

    Delene Visser

    1992-06-01

    Full Text Available Items from standardized tests as well as structured and semi-structured questionnaires were used to compile a profile of flight engineers involved in a labour dispute. Pertinent views of spouses were also measured. The subjects were found to be committed to their careers and identified with the goals of the company. However, the possibility of redundance was related to distrust in management, depression, anxiety, psychosomatic stress symptoms, lowered experience of general well-being, strained family life and impaired relations with their spouses. The findings provoke concern about the possible effects on in-flight safety and organizational effectiveness. Opsomming Items uit gestandaardiseerde toetse sowel as gestruktureerde en semi-gestruktureerde vraelyste is gebruik om 'n profiel van vlugingenieurs betrokke by 'n arbeidsdispuut saam te stel. Relevante sienings van eggenotes is ook gemeet. Daar is bevind dat die respondente toegewyd is aan hulle beroep en met die doelstellings van die organisasie identifiseer. Die moontlike uitfasering van hulle beroep was egter verbind aan wantroue in die bestuur, depressie, angs, psigo-somatiese stressimptome, verlaagde ervaring van algemene weslyn, gestremde gesinslewe en verswakte verhoudings met eggenotes. Die bevindings wek besorgdheid oor die moontlike gevolge vir aanboord veiligheid en organisatoriese effektiwiteit.

  17. Project-based learning in engineering design in Bulgaria: expectations, experiments and results

    Science.gov (United States)

    Raycheva, Regina Pavlova; Angelova, Desislava Ivanova; Vodenova, Pavlina Minkova

    2017-11-01

    Using a students' workshop as a laboratory, this article summarises the observation of three years' implementation of a new study module for a Bachelor Program in Engineering Design (Interior and Furniture Design) at the University of Forestry, Sofia, Bulgaria. The article offers an analysis of group dynamics and the difficulties and issues observed during the process. Data from survey questionnaires are interpreted; proposals are made for future research. The conclusion of the authors includes the following points: positive response by students, important encounter with successful professionals and companies; creative fulfilment and experience of team work. On the weak side is the experienced discomfort in public presentation, lack of verbal and graphic skills, interpersonal issues and pressure of real requirements from teachers and company; lack of adequate attention by the tutors. The need of better understanding a team 'code' of behaviour and preparation for an active learning method was felt. A proposal leading to a mixed-team organisation for better support of first-time participants in the module is made.

  18. Hypersonic Engine Leading Edge Experiments in a High Heat Flux, Supersonic Flow Environment

    Science.gov (United States)

    Gladden, Herbert J.; Melis, Matthew E.

    1994-01-01

    A major concern in advancing the state-of-the-art technologies for hypersonic vehicles is the development of an aeropropulsion system capable of withstanding the sustained high thermal loads expected during hypersonic flight. Three aerothermal load related concerns are the boundary layer transition from laminar to turbulent flow, articulating panel seals in high temperature environments, and strut (or cowl) leading edges with shock-on-shock interactions. A multidisciplinary approach is required to address these technical concerns. A hydrogen/oxygen rocket engine heat source has been developed at the NASA Lewis Research Center as one element in a series of facilities at national laboratories designed to experimentally evaluate the heat transfer and structural response of the strut (or cowl) leading edge. A recent experimental program conducted in this facility is discussed and related to cooling technology capability. The specific objective of the experiment discussed is to evaluate the erosion and oxidation characteristics of a coating on a cowl leading edge (or strut leading edge) in a supersonic, high heat flux environment. Heat transfer analyses of a similar leading edge concept cooled with gaseous hydrogen is included to demonstrate the complexity of the problem resulting from plastic deformation of the structures. Macro-photographic data from a coated leading edge model show progressive degradation over several thermal cycles at aerothermal conditions representative of high Mach number flight.

  19. Engineering expertise on shift in nuclear power plants: the foreign experience

    International Nuclear Information System (INIS)

    Melber, B.D.; Schreiber, R.E.

    1983-02-01

    This report describes the practices of selected foreign countries with providing engineering expertise on shift in nuclear power plants. The extent to which engineering expertise is made available and the alternative models of providing such expertise are presented. The implications of foreign practices for US consideration of alternatives are discussed, with reference to the shift technical advisor (STA) position and to a proposed shift engineer position. The procedure used to obtain information on foreign practices was primarily a review of the literature, including publications, presentations, and government and utility reports. There are two approaches that are in use to make engineering expertise available on shift: (1) employing a graduate engineer in a line management operations position; and (2) creating a specific engineering position for the purpose of providing expertise to the operations staff

  20. NASA's Robotics Mining Competition Provides Undergraduates Full Life Cycle Systems Engineering Experience

    Science.gov (United States)

    Stecklein, Jonette

    2017-01-01

    NASA has held an annual robotic mining competition for teams of university/college students since 2010. This competition is yearlong, suitable for a senior university engineering capstone project. It encompasses the full project life cycle from ideation of a robot design to actual tele-operation of the robot in simulated Mars conditions mining and collecting simulated regolith. A major required element for this competition is a Systems Engineering Paper in which each team describes the systems engineering approaches used on their project. The score for the Systems Engineering Paper contributes 25% towards the team's score for the competition's grand prize. The required use of systems engineering on the project by this competition introduces the students to an intense practical application of systems engineering throughout a full project life cycle.

  1. A unicorn's tale: Examining the experiences of Black women in engineering industry

    OpenAIRE

    Ross, Monique S

    2016-01-01

    Black women have recently been identified as the most educated demographic in the United States, and yet they are grossly underrepresented in engineering. They comprise 6.4 % of the U.S. population and only 0.72 % of engineering industry. Meanwhile, engineers have been identified as the key to the United States’ ability to maintain its prominence and leadership in a competitive global economy due to their contribution to maintaining and improving our infrastructures and standard of living. Th...

  2. Estimation of parasitic losses in a proposed mesoscale resonant engine: Experiment and model

    Science.gov (United States)

    Preetham, B. S.; Anderson, M.; Richards, C.

    2014-02-01

    A resonant engine in which the piston-cylinder assembly is replaced by a flexible cavity is realized at the mesoscale using flexible metal bellows to demonstrate the feasibility of the concept. A four stroke motoring technique is developed and measurements are performed to determine parasitic losses. A non-linear lumped parameter model is developed to evaluate the engine performance. Experimentally, the heat transfer and friction effects are separated by varying the engine speed and operating frequency. The engine energy flow diagram showing the energy distribution among various parasitic elements reveals that the friction loss in the bellows is smaller than the sliding friction loss in a typical piston-cylinder assembly.

  3. DESIGN OF EXPERIMENTS IN THE STUDY OF BAUXITE REFRACTORY CASTABLE PROPERTIES

    Directory of Open Access Journals (Sweden)

    Ilona Kieliba

    2017-07-01

    Full Text Available This paper presents results of an investigation of the influence of preparation conditions of low-cement refractory castables on their service properties using experiment planning methods. Using the orthogonal Plackett-Burman design, the influence of the amount of water, vibration time, curing conditions and firing conditions on the service properties of the finished refractory castable (apparent density, open porosity, permanent linear changes, Young's modulus, bending strength and compressive strength at ambient temperature is demonstrated. It is found that, among the investigated properties under the conditions of the conducted experiment, only the mixing time is a negligible factor that has no significant influence on the process of developing service properties of low-cement bauxite castables.

  4. Steeply dipping heaving bedrock, Colorado: Part 2 - Mineralogical and engineering properties

    Science.gov (United States)

    Noe, D.C.; Higgins, J.D.; Olsen, H.W.

    2007-01-01

    This paper describes the mineralogical and engineering properties of steeply dipping, differentially heaving bedrock, which has caused severe damage near the Denver area. Several field sites in heave-prone areas have been characterized using high sample densities, numerous testing methodologies, and thousands of sample tests. Hydrometer testing shows that the strata range from siltstone to claystone (33 to 66 percent clay) with occasional bentonite seams (53 to 98 percent clay mixed with calcite). From X-ray diffraction analyses, the claystone contains varying proportions of illite-smectite and discrete (pure) smectite, and the bentonite contains discrete smectite. Accessory minerals include pyrite, gypsum, calcite, and oxidized iron compounds. The dominant exchangeable cation is Ca2+, except where gypsum is prevalent, and Mg2+ and Na1+ are elevated. Scanning electron microscope analyses show that the clay fabric is deformed and porous and that pyrite is absent within the weathered zone. Unified Soil Classification for the claystone varies from CL to CH, and the bentonite is CH to MH. Average moisture content values are 17 percent for claystone and 32 percent for bentonite, and these are typically 0 to 5 percent lower than the plastic limit. Swell-consolidation and suction testing shows a full range of swelling potentials from low to very high. These findings confirm that type I (bed-parallel, symmetrical to asymmetrical) heave features are strongly associated with changes in bedrock composition and mineralogy. Composition changes are not necessarily a factor for type II (bed-parallel to bed-oblique, strongly asymmetrical) heave features, which are associated with movements along subsurface shear zones.

  5. Engineering properties of lightweight geopolymer synthesized from coal bottom ash and rice husk ash

    Science.gov (United States)

    Thang, Nguyen Hoc; Hoa, Nguyen Ngoc; Quyen, Pham Vo Thi Ha; Tuyen, Nguyen Ngoc Kim; Anh, Tran Vu Thao; Kien, Pham Trung

    2018-04-01

    Geopolymer technology was developed by Joseph Davidovits in 1970s based on reactions among alumino-silicate resources in high alkaline conditions. Geopolymer has been recently gaining attention as an alternative binder for Ordinary Portland cement (OPC) due to its low energy and CO2 burden. The raw materials used for geopolymerization normally contain high SiO2 and Al2O3 in the chemical compositions such as meta-kaoline, rice husk ash, fly ash, bottom ash, blast furnace slag, red mud, and others. Moreover, in this paper, coal bottom ash (CBA) and rice husk ash (RHA), which are industrial and agricultural wastes, respectively, were used as raw materials with high alumino-silicate resources. Both CBA and RHA were mixed with sodium hydroxide (NaOH) solution for 20 minutes to obtain the geopolymer pastes. The pastes were filled in 5-cm cube molds according to ASTM C109/C109M 99, and then cured at room condition for hardening of the geopolymer specimens. After 24 hours, the specimens were removed out of the molds and continuously cured at room condition for 27 days. The geopolymer-based materials were then tested for engineering properties such as compressive strength (MPa), volumetric weight (kg/m3), and water absorption (kg/m3). Results indicated that the material can be considered lightweight with volumetric weight from 1192 to 1425 kg/m3; compressive strength at 28 days is in the range of 12.38 to 37.41 MPa; and water absorption is under 189.92 kg/m3.

  6. Strain and Defect Engineering for Tailored Electrical Properties in Perovskite Oxide Thin Films and Superlattices

    Science.gov (United States)

    Hsing, Greg Hsiang-Chun

    Functional complex-oxides display a wide spectrum of physical properties, including ferromagnetism, piezoelectricity, ferroelectricity, photocatalytic and metal-insulating transition (MIT) behavior. Within this family, oxides with a perovskite structure have been widely studied, especially in the form of thin films and superlattices (heterostructures), which are strategically and industrially important because they offer a wide range of opportunities for electronic, piezoelectric and sensor applications. The first part of my thesis focuses on understanding and tuning of the built-in electric field found in PbTiO3/SrTiO3 (PTO/STO) ferroelectric superlattices and other ferroelectric films. The artificial layering in ferroelectric superlattices is a potential source of polarization asymmetry, where one polarization state is preferred over another. One manifestation of this asymmetry is a built-in electric field associated with shifted polarization hysteresis. Using off-axis RF-magnetron sputtering, we prepared several compositions of PTO/STO superlattice thin films; and for comparison PbTiO3/SrRuO 3 (PTO/SRO) superlattices, which have an additional intrinsic compositional asymmetry at the interface. Both theoretical modeling and experiments indicate that the layer-by-layer superlattice structure aligns the Pb-O vacancy defect dipoles in the c direction which contributes significantly to the built-in electric field; however the preferred polarization direction is different between the PTO/STO and PTO/SRO interface. By designing a hybrid superlattice that combines PTO/STO and PTO/SRO superlattices, we show the built-in electric field can be tuned to zero by changing the composition of the combo-superlattice. The second part of my thesis focuses on the epitaxial growth of SrCrO 3 (SCO) films. The inconsistent reports regarding its electrical and magnetic properties through the years stem from the compositionally and structurally ill-defined polycrystalline samples, but

  7. Experiences in Using Practitioner’s Checklists to Evaluate the Relevance of Experiments Reported in Requirements Engineering

    NARCIS (Netherlands)

    Daneva, Maia; Sikkel, Nicolaas; Condori-Fernandez, Nelly; Herrmann, Andrea

    Background: Requirements Engineering (RE) researchers recognize that for RE methods to be adopted in industry, practitioners should be able to evaluate the relevance of a study to their practice. Kitchenham et al proposed a set of perspective-based checklists, which demonstrated to be a useful

  8. Analysis of blended fuel properties and cycle-to-cycle variation in a diesel engine with a diethyl ether additive

    International Nuclear Information System (INIS)

    Ali, Obed M.; Mamat, Rizalman; Masjuki, H.H.; Abdullah, Abdul Adam

    2016-01-01

    Highlights: • Viability of diethyl ether additive to improve palm biodiesel–diesel blend. • Numerical analysis of engine cyclic variation at different additive ratios. • Physicochemical properties of the blends improved with diethyl ether additive. • Blended fuel heating value is significantly affected. • Blended fuel with 4% diethyl ether shows comparable engine cyclic variation to diesel. - Abstract: In this study, the effect of adding small portions of a diethyl ether additive to biodiesel–diesel blended fuel (B30) was investigated. This study includes an evaluation of the fuel properties and a combustion analysis, specifically, an analysis of the cyclic variations in diesel engines. The amount of additive used with B30 is 2%, 4%, 6% and 8% (by volume). The experimental engine test was conducted at 2500 rpm which produce maximum torque, and the in-cylinder pressure data were collected over 200 consecutive engine cycles for each test. The indicated mean effective pressure time series is analyzed using the coefficient of variation and the wavelet analysis method. The test results for the properties show a slight improvement in density and acid value with a significant decrease in the viscosity, pour point and cloud point of the blended fuel with an 8% additive ratio by 26.5%, 4 °C and 3 °C, respectively, compared with blended fuel without additive. However, the heating value is reduced by approximately 4% with increasing the additive ratio to 8%. From the wavelet power spectrum, it is observed that the intermediate and long-term periodicities appear in diesel fuel, while the short-period oscillations become intermittently visible in pure blended fuel. The coefficient of variation for B30 was the lowest and increased as the additive ratios increased, which agrees with the wavelet analysis results. Furthermore, the spectral power increased with an increase in the additive ratio, indicating that the additive has a noticeable effect on increasing the

  9. The Effect of an Open-Ended Design Experience on Student Achievement in an Engineering Laboratory Course

    Directory of Open Access Journals (Sweden)

    Matthew Cullin

    2017-11-01

    Full Text Available This study explores the effect of incorporating an Open-Ended Design Experience (OEDE into an undergraduate materials science laboratory taken by third-year mechanical engineering students. The focus of the OEDE was carbon fiber reinforced plastics and sandwich structures. The results indicate that the incorporation of OEDE’s in laboratory courses produces significant benefits in terms of student engagement, participation, and perception of competence. In addition, the OEDE was found to enhance students’ ability to apply related concepts as compared to non-OEDE lab activities. The authors conclude that the incorporation of OEDE’s can increase the effectiveness of engineering laboratory courses.

  10. Exploring the experiences of female students in introductory project-based engineering courses at two- and four-year institutions

    Science.gov (United States)

    Swan, Amy K.

    2011-12-01

    This qualitative study explored the experiential and contextual factors that shaped female students' pathways into introductory project-based engineering classes at two community colleges and one four-year institution, as well as female students' experiences within and outside of these classes. The study was framed by Social Cognitive Career Theory (SCCT) (Lent, Brown & Hackett, 1996) and Bronfenbrenner's (1979) ecological systems theory. Findings were based on analyses of data gathered through multiple methods: observations; individual interviews with female students; focus group interviews with project teams; and document collection. The findings of this study revealed that while positive experiences with math or science were a likely pre-cursor to engineering interest, experiential learning appeared to be a more powerful force in fostering students' engineering interest. Specifically, participants developed an interest in engineering through academic, professional, and extracurricular engineering- and design-related activities that familiarized them with the tasks and skills involved in engineering work and helped them develop a sense of selfefficacy with regard to this work. Interest and self-efficacy, in turn, played a role in students' postsecondary educational decision-making processes, as did contextual factors including families and finances. This study's findings also showed that participants' project teams were a critically important microsystem within participants' ecological environments. Within this sometimes "chilly" microsystem, female students negotiated intrateam processes, which were in some cases affected by gender norms. Intrateam processes that influenced female students' project-based learning experiences included: interpersonal dynamics; leadership; and division of labor. This study also identified several ways in which the lived experiences of participants at the community colleges were different from, or similar to, those of participants

  11. Mechanical properties and cellular response of novel electrospun nanofibers for ligament tissue engineering: Effects of orientation and geometry.

    Science.gov (United States)

    Pauly, Hannah M; Kelly, Daniel J; Popat, Ketul C; Trujillo, Nathan A; Dunne, Nicholas J; McCarthy, Helen O; Haut Donahue, Tammy L

    2016-08-01

    Electrospun nanofibers are a promising material for ligamentous tissue engineering, however weak mechanical properties of fibers to date have limited their clinical usage. The goal of this work was to modify electrospun nanofibers to create a robust structure that mimics the complex hierarchy of native tendons and ligaments. The scaffolds that were fabricated in this study consisted of either random or aligned nanofibers in flat sheets or rolled nanofiber bundles that mimic the size scale of fascicle units in primarily tensile load bearing soft musculoskeletal tissues. Altering nanofiber orientation and geometry significantly affected mechanical properties; most notably aligned nanofiber sheets had the greatest modulus; 125% higher than that of random nanofiber sheets; and 45% higher than aligned nanofiber bundles. Modifying aligned nanofiber sheets to form aligned nanofiber bundles also resulted in approximately 107% higher yield stresses and 140% higher yield strains. The mechanical properties of aligned nanofiber bundles were in the range of the mechanical properties of the native ACL: modulus=158±32MPa, yield stress=57±23MPa and yield strain=0.38±0.08. Adipose derived stem cells cultured on all surfaces remained viable and proliferated extensively over a 7 day culture period and cells elongated on nanofiber bundles. The results of the study suggest that aligned nanofiber bundles may be useful for ligament and tendon tissue engineering based on their mechanical properties and ability to support cell adhesion, proliferation, and elongation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Supplementation of exogenous adenosine 5'-triphosphate enhances mechanical properties of 3D cell-agarose constructs for cartilage tissue engineering.

    Science.gov (United States)

    Gadjanski, Ivana; Yodmuang, Supansa; Spiller, Kara; Bhumiratana, Sarindr; Vunjak-Novakovic, Gordana

    2013-10-01

    Formation of tissue-engineered cartilage is greatly enhanced by mechanical stimulation. However, direct mechanical stimulation is not always a suitable method, and the utilization of mechanisms underlying mechanotransduction might allow for a highly effective and less aggressive alternate means of stimulation. In particular, the purinergic, adenosine 5'-triphosphate (ATP)-mediated signaling pathway is strongly implicated in mechanotransduction within the articular cartilage. We investigated the effects of transient and continuous exogenous ATP supplementation on mechanical properties of cartilaginous constructs engineered using bovine chondrocytes and human mesenchymal stem cells (hMSCs) encapsulated in an agarose hydrogel. For both cell types, we have observed significant increases in equilibrium and dynamic compressive moduli after transient ATP treatment applied in the fourth week of cultivation. Continuous ATP treatment over 4 weeks of culture only slightly improved the mechanical properties of the constructs, without major changes in the total glycosaminoglycan (GAG) and collagen content. Structure-function analyses showed that transiently ATP-treated constructs, and in particular those based on hMSCs, had the highest level of correlation between compositional and mechanical properties. Transiently treated groups showed intense staining of the territorial matrix for GAGs and collagen type II. These results indicate that transient ATP treatment can improve functional mechanical properties of cartilaginous constructs based on chondrogenic cells and agarose hydrogels, possibly by improving the structural organization of the bulk phase and territorial extracellular matrix (ECM), that is, by increasing correlation slopes between the content of the ECM components (GAG, collagen) and mechanical properties of the construct.

  13. Influence of instruments performance and material properties on exposure assessment of airborne engineered nanomaterials

    DEFF Research Database (Denmark)

    Levin, Marcus

    Over the last decades, materials engineered of nanosized structures have increased tremendously, in terms of both produced tonnage and economic market share. This, together with the fact that some of these engineered nanomaterials have shown an increased toxicological effect in humans as compared...... characteristics, and highlights necessary improvements for future adaptions of new metrics into regulatory testing and occupational exposure limits....

  14. Learning by Brewing: Beer Production Experiments in the Chemical Engineering Laboratory

    Science.gov (United States)

    Cerretani, Colin; Kelkile, Esayas; Landry, Alexandra

    2017-01-01

    We discuss the successful creation and implementation of a biotechnology track within the chemical engineering unit operations course. The track focuses on engineering principles relevant to brewing. Following laboratory modules investigating heat transfer processes and yeast fermentation kinetics, student groups design and implement a project to…

  15. A Multi- and Cross-Disciplinary Capstone Experience in Engineering Art: Animatronic Polar Bear

    Science.gov (United States)

    Sirinterlikci, Arif; Toukonen, Kayne; Mason, Steve; Madison, Russel

    2005-01-01

    An animatronic robot was designed and constructed for the 2003 Annual Student Robotic Technology and Engineering Challenge organized by the Robotics International (RI) association of the Society of Manufacturing Engineers (SME). It was also the senior capstone design project for two of the design team members. After a thorough study of body and…

  16. Gamification in teaching maintenance engineering : a Dutch experience in the rolling stock management learning

    NARCIS (Netherlands)

    Martinetti, Alberto; Parada Puig, Jorge Eduardo; Oude Alink, Charlotte; Thalen, Jos; van Dongen, Leonardus Adriana Maria

    2017-01-01

    The aim of this study is to evaluate the application of an innovative serious game, based on the asset management of rolling stock, in the training of future maintenance engineers within the master course in mechanical engineering at the University of Twente. The Logistic Support Game (LSG) is a

  17. New Architectures for Presenting Search Results Based on Web Search Engines Users Experience

    Science.gov (United States)

    Martinez, F. J.; Pastor, J. A.; Rodriguez, J. V.; Lopez, Rosana; Rodriguez, J. V., Jr.

    2011-01-01

    Introduction: The Internet is a dynamic environment which is continuously being updated. Search engines have been, currently are and in all probability will continue to be the most popular systems in this information cosmos. Method: In this work, special attention has been paid to the series of changes made to search engines up to this point,…

  18. The persuasion and security awareness experiment: reducing the success of social engineering attacks

    NARCIS (Netherlands)

    Bullee, Jan-Willem; Montoya, L.; Pieters, Wolter; Junger, Marianne; Hartel, Pieter H.

    Objectives: The aim of the current study is to explore to what extent an intervention reduces the effects of social engineering (e.g. the obtaining of access by persuasion) in an office environment. In particular, we study the effect of authority during a `social engineering' attack. Methods: 31

  19. Exploration of the Lived Experiences of Undergraduate Science, Technology, Engineering, and Mathematics Minority Students

    Science.gov (United States)

    Snead-McDaniel, Kimberly

    2010-01-01

    An expanding ethnicity gap exists in the number of students pursuing science, technology, engineering, and mathematics (STEM) careers in the United States. The National Action Council for Minorities in Engineering revealed that the number of minorities pursuing STEM degrees and careers has declined over the past few years. The specific origins of…

  20. The Romanian educational system in nuclear engineering field - experience and new approaches

    International Nuclear Information System (INIS)

    Dragusin, O.; Burghelea, A.

    2001-01-01

    In this paper we would like to present the actual status of the education in the nuclear engineering field at 'Pantholic' University Bucharest, Romania, Power Engineering Faculty, Nuclear Power Plant Department, and also the efforts of integration of the educational system of Romania into the international system and the development of new concepts concerning the education of the new specialists generation. (authors)

  1. Enhancing Critical Thinking across the Undergraduate Experience: An Exemplar from Engineering

    Science.gov (United States)

    Ralston, Patricia A.; Bays, Cathy L.

    2013-01-01

    Faculty in a large, urban school of engineering designed a longitudinal study to assess the critical thinking skills of undergraduate students as they progressed through the engineering program. The Paul-Elder critical thinking framework was used to design course assignments and develop a holistic assessment rubric. The curriculum was re-designed…

  2. Web Services as Product Experience Augmenters and the Implications for Requirements Engineering: A Position Paper

    NARCIS (Netherlands)

    van Eck, Pascal; Nijholt, Antinus; Wieringa, Roelf J.

    There is currently little insight into what requirement engineering for web services is and in which context it will be carried out. In this position paper, we investigate requirements engineering for a special kind of web services, namely web services that are used to augment the perceived value of

  3. Mechanical Properties of Boehmite Evaluated by Atomic Force Microscopy Experiments and Molecular Dynamic Finite Element Simulations

    International Nuclear Information System (INIS)

    Fankhanel, J.; Daum, B.; Kempe, A.; Rolfes, R.; Silbernagl, D.; Khorasani, M.Gh.Z.; Sturm, H.; Sturm, H.

    2016-01-01

    Boehmite nanoparticles show great potential in improving mechanical properties of fiber reinforced polymers. In order to predict the properties of nanocomposites, knowledge about the material parameters of the constituent phases, including the boehmite particles, is crucial. In this study, the mechanical behavior of boehmite is investigated using Atomic Force Microscopy (AFM) experiments and Molecular Dynamic Finite Element Method (MDFEM) simulations. Young’s modulus of the perfect crystalline boehmite nanoparticles is derived from numerical AFM simulations. Results of AFM experiments on boehmite nanoparticles deviate significantly. Possible causes are identified by experiments on complementary types of boehmite, that is, geological and hydrothermally synthesized samples, and further simulations of imperfect crystals and combined boehmite/epoxy models. Under certain circumstances, the mechanical behavior of boehmite was found to be dominated by inelastic effects that are discussed in detail in the present work. The studies are substantiated with accompanying X-ray diffraction and Raman experiments.

  4. Educational analysis of a first year engineering physics experiment on standing waves: based on the ACELL approach

    International Nuclear Information System (INIS)

    Bhathal, Ragbir; Sharma, Manjula D; Mendez, Alberto

    2010-01-01

    This paper describes an educational analysis of a first year physics experiment on standing waves for engineering students. The educational analysis is based on the ACELL (Advancing Chemistry by Enhancing Learning in the Laboratory) approach which includes a statement of educational objectives and an analysis of student learning experiences. The experiment is likely to be found in many physics departments, hence is appropriate to illustrate the ACELL approach in physics. The concepts associated with standing waves are difficult; however, they are underpinned by mathematical formulation which lend themselves to be visualized in experiments. The challenge is to strike a balance between these two for the particular student cohort. In this study, this balance is achieved by using simple equipment and providing appropriate scaffolds for students to associate abstract concepts with concrete visuals. In essence the experiment is designed to adequately manage cognitive resources. Students work in pairs and are questioned and assisted by demonstrators and academic staff during a 2 h practical class. Students were surveyed using the ACELL instrument. Analysis of the data showed that by completing the practical students felt that their understanding of physics had increased. Furthermore, students could see the relevance of this experiment to their engineering studies and that it provided them with an opportunity to take responsibility for their own learning. Overall they had a positive learning experience. In short there is a lot of dividend from a small outlay of resources.

  5. Validation of scaffold design optimization in bone tissue engineering: finite element modeling versus designed experiments.

    Science.gov (United States)

    Uth, Nicholas; Mueller, Jens; Smucker, Byran; Yousefi, Azizeh-Mitra

    2017-02-21

    This study reports the development of biological/synthetic scaffolds for bone tissue engineering (TE) via 3D bioplotting. These scaffolds were composed of poly(L-lactic-co-glycolic acid) (PLGA), type I collagen, and nano-hydroxyapatite (nHA) in an attempt to mimic the extracellular matrix of bone. The solvent used for processing the scaffolds was 1,1,1,3,3,3-hexafluoro-2-propanol. The produced scaffolds were characterized by scanning electron microscopy, microcomputed tomography, thermogravimetric analysis, and unconfined compression test. This study also sought to validate the use of finite-element optimization in COMSOL Multiphysics for scaffold design. Scaffold topology was simplified to three factors: nHA content, strand diameter, and strand spacing. These factors affect the ability of the scaffold to bear mechanical loads and how porous the structure can be. Twenty four scaffolds were constructed according to an I-optimal, split-plot designed experiment (DE) in order to generate experimental models of the factor-response relationships. Within the design region, the DE and COMSOL models agreed in their recommended optimal nHA (30%) and strand diameter (460 μm). However, the two methods disagreed by more than 30% in strand spacing (908 μm for DE; 601 μm for COMSOL). Seven scaffolds were 3D-bioplotted to validate the predictions of DE and COMSOL models (4.5-9.9 MPa measured moduli). The predictions for these scaffolds showed relative agreement for scaffold porosity (mean absolute percentage error of 4% for DE and 13% for COMSOL), but were substantially poorer for scaffold modulus (51% for DE; 21% for COMSOL), partly due to some simplifying assumptions made by the models. Expanding the design region in future experiments (e.g., higher nHA content and strand diameter), developing an efficient solvent evaporation method, and exerting a greater control over layer overlap could allow developing PLGA-nHA-collagen scaffolds to meet the mechanical requirements for

  6. CAD and 3d-printing integration experience in the curriculum of engineers education

    Directory of Open Access Journals (Sweden)

    V. V. Zelentsov

    2016-01-01

    Full Text Available The paper examines the results of using the 3d-printing educational methodology for training the students in the spacecraft-configuration developing area.The first purpose of the considered methodology practice is to implement the rapid-prototyping skills into the educational process, to provide perfection of the student knowledge in configuring the internal on-board equipment of the spacecraft. The second purpose – is to habituate the students to the main principles of the available CAM technologies, to fill the available educational gap in the area of information support of the spacecraft life-cycle.The proposed curriculum includes six training exercises based on a special “Engineering drawing” course unit. The training exercises require using the SolidWorks geometric-simulation software. The preliminary obtained virtual prototypes of the spacecraft configuration elements are subjected to 3d-printing and assembled into a physical configuration model. The physical configuration models are obtained using one of the most accessible rapid-prototyping technologies – 3d-printing of extrusion type. Practicing in 3d-printing provides developing the student skills in managing all other digital-program control devices.The specified first experience of integrating the computer geometricsimulation methodology and the 3d-printing practices in a single course unit has proved: developing the physical-configuration models heightens the student interest to the configuration training.A ready-made physical model does not excuse the available configuration mistakes unlike a virtual model where the component interferences may remain undetected. So, developing a physical model requires additional endeavor and responsibility. Developing a project in a team has proved to be an effective means for solving a common creative problem.The first test of the proposed methodology has shown the importance of perfect adjustment of the available 3d-printing process and

  7. Quick Reaction Evaluation of Materials and Processes. Delivery Order 0011: Engineering Properties, Fatigue, and Crack Growth Data on SCS-6/Ti-6Al-4V Titanium Matrix Composite (16 Ply) Panels

    Science.gov (United States)

    2009-05-01

    tabs were bonded to the specimen using a TIG welding process to ensure adhesion of the tabs throughout the experiment. The shear specimens and the...AFRL-RX-WP-TR-2010-4175 QUICK REACTION EVALUATION OF MATERIALS AND PROCESSES Delivery Order 0011: Engineering Properties, Fatigue, and Crack...From - To) May 2009 Final 03 April 2006 – 29 May 2009 4. TITLE AND SUBTITLE QUICK REACTION EVALUATION OF MATERIALS AND PROCESSES Delivery Order

  8. Optimization experiment of gas oil direct injection valve for CNG dual fuel diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Kim, B.Y. [Chonnam National University Graduate School, Jeonju (Korea); Park, C. K. [Chonnam National University, Jeonju (Korea)

    1999-04-01

    In this study, we studied for a conversion from diesel engine to natural gas dual fuel engine. For this experimental, we tested about the injection quantity characteristics of pilot valve with the plunger diameter at the retraction volume and investigated to the engine performance and exhaust emissions with the nozzle hole number and injection nozzle diameter. As a result, when the plunger diameter is 7.5 mm at the retraction volume, 25 mm{sup 3}/st, the injection quantity characteristics develop. Also, when a nozzle type is 4*{phi} 0.24, total hydrocarbon(THC) emission reduce at low equivalence ratio. (author). 5 refs., 10 figs., 2 tabs.

  9. Experiments for the Undergraduate Laboratory that Illustrate the Size-Exclusion Properties of Zeolite Molecular Sieves

    Science.gov (United States)

    Cooke, Jason; Henderson, Eric J.

    2009-01-01

    Experiments are presented that demonstrate the size-exclusion properties of zeolites and reveal the reason for naming zeolites "molecular sieves". If an IR spectrometer is available, the adsorption or exclusion of alcohols of varying sizes from dichloromethane or chloroform solutions can be readily demonstrated by monitoring changes in the…

  10. Data-driven property verification of grey-box systems by Bayesian experiment design

    NARCIS (Netherlands)

    Haesaert, S.; Van den Hof, P.M.J.; Abate, A.

    2015-01-01

    A measurement-based statistical verification approach is developed for systems with partly unknown dynamics. These grey-box systems are subject to identification experiments which, new in this contribution, enable accepting or rejecting system properties expressed in a linear-time logic. We employ a

  11. Predicting nitrous oxide emissions from manure properties and soil moisture: An incubation experiment

    DEFF Research Database (Denmark)

    Baral, Khagendra Raj; Arthur, Emmanuel; Olesen, Jørgen Eivind

    2016-01-01

    Field-applied manure is a source of essential plant nutrients, but benefits may be partly offset by high rates of nitrous oxide (N2O) emissions, as modified by manure characteristics and soil properties. In a 28-d incubation experiment we quantified short-term emissions of N2O from a sandy loam...

  12. Model Experiments on Chemical Properties of Superheavy Elements in Aqueous Solutions

    CERN Document Server

    Szeglowski, Z

    2003-01-01

    This paper presents a brief review of model experiments on investigation of chemical properties of transactinide elements, ranging from 104 to 116. The possibilities of isolation of the nuclei of these elements from nuclear reaction products, using the ion-exchange method, are also considered.

  13. Statistical properties of compartmental model parameters extracted from dynamic positron emission tomography experiments

    International Nuclear Information System (INIS)

    Mazoyer, B.M.; Huesman, R.H.; Budinger, T.F.; Knittel, B.L.

    1986-01-01

    Over the past years a major focus of research in physiologic studies employing tracers has been the computer implementation of mathematical methods of kinetic modeling for extracting the desired physiological parameters from tomographically derived data. A study is reported of factors that affect the statistical properties of compartmental model parameters extracted from dynamic positron emission tomography (PET) experiments

  14. Study on specifics of thermophysical properties of supercritical fluids in power engineering applications

    International Nuclear Information System (INIS)

    Mann, David; Pioro, Igor

    2015-01-01

    SuperCritical Pressures (SCPs) and SuperCritical Fluids (SFCs) are widely used in many industries worldwide. The largest application of SCPs is in the power industry in advanced coal-fired power plants. It is well-known that moving from subcritical-pressure power plants to SCP power plants increases gross thermal efficiency from 38-42% to about 50-55%. Despite all advances in thermal power-plants design and operation worldwide, they are still considered as not “environmentally friendly” due to significant carbon-dioxide emissions and air pollution as a result of the combustion process. In addition, coal-fired power-plants also produce virtual mountains of slag and ash, and other gas emissions that may contribute to acid rains. Therefore, the demand for clean, non-fossil-based electricity is growing. Due to this, nuclear power is considered as a basis for future electricity generation in the world. One of the major problems with current fleet of Nuclear Power Plants (NPPs) is their relatively low thermal efficiencies, especially, of water-cooled-reactor NPPs (the vast majority of NPPs) (30-36%), compared to those of advanced thermal power plants (55-62%). Based on that, next generation or Generation-IV reactors corresponding to those NPPs should definitely be more efficient. Higher level of thermal efficiencies can be reached only due to higher temperatures and, in some cases, higher pressures inside reactors and, especially, in power cycles of Generation-IV NPPs. Analysis of the six concepts of Generation-IV reactors and NPPs shows that three reactor concepts will use SCFs as reactor coolants (helium and water) and all concepts can be linked to SCFs as working fluids in power cycles (SC helium and /or carbon dioxide in the Brayton gas-turbine cycle, and SC water in the Rankine steam-turbine cycle). Therefore, the exact knowledge of specifics of thermophysical properties of SC helium, water and carbon dioxide is very important for any advances in these new

  15. An Introduction to the Cost of Engineering and Institutional Controls at Brownfield Properties

    Science.gov (United States)

    This fact sheet introduces and explores the costs of site cleanup and, where cleanup leaves site contamination that restricts reuse, outlines the engineering and institutional controls and their monitoring and maintenance costs over a longer time frame.

  16. Band Engineering Small Bandgap p-Type Semiconductors: Investigations of their Optical and Photoelectrochemical Properties

    Science.gov (United States)

    Zoellner, Brandon

    Mixed-metal oxides containing Mn(II), Cu(I), Ta(V), Nb(V), and V(V) were investigated for their structures and properties as new p-type semiconductors and in the potential applications involving the photocatalytic conversion of water into hydrogen and oxygen. Engineering of the bandgaps was achieved by combining metal cations that have halffilled (Mn 3d5) or filled (Cu 3d10) d-orbitals together with metal cations that have empty (V/Nb/Ta 3/4/5 d0) d-orbitals. The research described herein focuses on the synthesis, optical, electronic, and photocatalytic properties of the metal-oxide semiconductors MnV2O6, Cu3VO 4, CuNb1-xTaxO3, and Cu5(Ta1-xNbx)11O30. Powder X-ray diffraction was used to probe their phase purity as well as atomic-level crystallographic details, i.e. shifts of lattice parameters, chemical compositions, and changes in local bonding environments. Optical measurements revealed visible-light bandgap sizes of ˜1.17 eV (Cu3VO4), ˜1.45 eV (MnV2O6), ˜1.89-1.97 eV (CuNb1-xTa xO3), and ˜1.97-2.50 eV (Cu5(Ta1-xNb x)11O30). The latter two were found to systematically vary as a function of composition. Electrochemical impedance spectroscopy measurements of MnV2O6 and Cu3VO 4 provided the first experimental characterization of the energetic positions of the valence and conduction bands with respect to the water oxidation and reduction potentials, as well as confirmed the p-type nature of each semiconductor. The valence and conduction band energies were found to be suitable for driving either one or both of the water-splitting half reaction (i.e. 2H+ → H2 and 2H2O → O2 + 4H+). Photoelectrochemical measurements on polycrystalline films of the Cu(I)-based semiconductors under visible-light irradiation produced cathodic currents indicative of p-type semiconductor character and chemical reduction at their surfaces in the electrolyte solution. The stability of the photocurrents was increased by the addition of CuO oxide particles either externally deposited or

  17. Engineering Encounters: Reverse Engineering

    Science.gov (United States)

    McGowan, Veronica Cassone; Ventura, Marcia; Bell, Philip

    2017-01-01

    This column presents ideas and techniques to enhance your science teaching. This month's issue shares information on how students' everyday experiences can support science learning through engineering design. In this article, the authors outline a reverse-engineering model of instruction and describe one example of how it looked in our fifth-grade…

  18. Numerical investigation of natural gas direct injection properties and mixture formation in a spark ignition engine

    Directory of Open Access Journals (Sweden)

    Yadollahi Bijan

    2014-01-01

    Full Text Available In this study, a numerical model has been developed in AVL FIRE software to perform investigation of Direct Natural Gas Injection into the cylinder of Spark Ignition Internal Combustion Engines. In this regard two main parts have been taken into consideration, aiming to convert an MPFI gasoline engine to direct injection NG engine. In the first part of study multi-dimensional numerical simulation of transient injection process, mixing and flow field have been performed via three different validation cases in order to assure the numerical model validity of results. Adaption of such a modeling was found to be a challenging task because of required computational effort and numerical instabilities. In all cases present results were found to have excellent agreement with experimental and numerical results from literature. In the second part, using the moving mesh capability the validated model has been applied to methane Injection into the cylinder of a Direct Injection engine. Five different piston head shapes along with two injector types have been taken into consideration in investigations. A centrally mounted injector location has been adapted to all cases. The effects of injection parameters, combustion chamber geometry, injector type and engine RPM have been studied on mixing of air-fuel inside cylinder. Based on the results, suitable geometrical configuration for a NG DI Engine has been discussed.

  19. Morphological and Strength Properties of Tanjung Bin Coal Ash Mixtures for Applied in Geotechnical Engineering Work

    OpenAIRE

    Awang, Abd. Rahim; Marto, Aminaton; Makhtar, Ahmad Maher

    2012-01-01

    In Malaysia, coal has been used as a raw material to generate electricity since 1988. In the past, most of the wastage of coal burning especially the bottom ash was not managed properly as it was dumped in the waste pond and accumulated drastically.This paper focuses on some properties of coal ash mixtures (fly  ash and bottom ash mixtures) from Tanjung Bin power plant. The characteristics studied were morphological properties, compaction behaviour and strength properties. Strength properties...

  20. Integrating E-Learning and Classroom Learning for Engineering Quality Control unit - Curtin University Experience

    Directory of Open Access Journals (Sweden)

    Ali M. Darabi Golshani

    2011-08-01

    Full Text Available Engineering employers expect engineering graduates to possess a wide range of skills that goes beyond their technical knowledge. It is vital that graduates have skills which demonstrate that they are responsible for their own development and careers. Some of these skills include; communication abilities, organizational skills, self-promotion, the ability to work as part of a team, be an effective problem solver, be a critical thinker, have good negotiation skills, have the ability to be a leader and being able to network effectively. Department of Civil Engineering at Curtin University of Technology in Perth, Australia offers a Master of Engineering Management degree for Engineers from various disciplines. One of the units taught in this Master degree program is Engineering Quality Control. It was decided to incorporate these non-technical skills in this unit by using an e-learning platform (Blackboard together with an adaptation of the Seven Principles of Good Practice and Dr Meredith Belbin’s team role theory to divide participants into groups. At the end of the unit, most of the participants were showing improvements in their non-technical skills.