NASA Astrophysics Data System (ADS)
Schulman, Kathleen M.
This study fills a gap in the research literature regarding the types of instructional support provided by instructors in online introductory chemistry laboratory courses that employ chemistry simulations as laboratory exercises. It also provides information regarding students' perceptions of the effectiveness of that instructional support. A multiple case study methodology was used to carry out the research. Two online introductory chemistry courses were studied at two community colleges. Data for this study was collected using phone interviews with faculty and student participants, surveys completed by students, and direct observation of the instructional designs of instructional support in the online Blackboard web sites and the chemistry simulations used by the participating institutions. The results indicated that the instructors provided multiple types of instructional support that correlated with forms of effective instructional support identified in the research literature, such as timely detailed feedback, detailed instructions for the laboratory experiments, and consistency in the instructional design of lecture and laboratory course materials, including the chemistry lab simulation environment. The students in one of these courses identified the following as the most effective types of instructional support provided: the instructor's feedback, opportunities to apply chemistry knowledge in the chemistry lab exercises, detailed procedures for the simulated laboratory exercises, the organization of the course Blackboard sites and the chemistry lab simulation web sites, and the textbook homework web sites. Students also identified components of instructional support they felt were missing. These included a desire for more interaction with the instructor, more support for the simulated laboratory exercises from the instructor and the developer of the chemistry simulations, and faster help with questions about the laboratory exercises or experimental calculations. Students believed that having this additional instructional support would lead to increased understanding of the laboratory exercises, allowing them to complete them with less difficulty, and giving them increased access to the instructor. Recommendations for the instructors of these two courses include: increased participation in the online course environment, increased emphasis on laboratory safety, and increased emphasis on the differences between simulated and real life chemistry laboratory experiments.
NASA Astrophysics Data System (ADS)
Javidi, Giti
2005-07-01
This study was designed to investigate an alternative to the use of traditional physical laboratory activities in a communication systems course. Specifically, this study examined whether as an alternative, computer simulation is as effective as physical laboratory activities in teaching college-level electronics engineering education students about the concepts of signal transmission, modulation and demodulation. Eighty undergraduate engineering students participated in the study, which was conducted at a southeastern four-year university. The students were randomly assigned to two groups. The groups were compared on understanding the concepts, remembering the concepts, completion time of the lab experiments and perception toward the laboratory experiments. The physical group's (n = 40) treatment was to conduct laboratory experiments in a physical laboratory. The students in this group used equipment in a controlled electronics laboratory. The Simulation group's (n = 40) treatment was to conduct similar experiments in a PC laboratory. The students in this group used a simulation program in a controlled PC lab. At the completion of the treatment, scores on a validated conceptual test were collected once after the treatment and again three weeks after the treatment. Attitude surveys and qualitative study were administered at the completion of the treatment. The findings revealed significant differences, in favor of the simulation group, between the two groups on both the conceptual post-test and the follow-up test. The findings also revealed significant correlation between simulation groups' attitude toward the simulation program and their post-test scores. Moreover, there was a significant difference between the two groups on their attitude toward their laboratory experience in favor of the simulation group. In addition, there was significant difference between the two groups on their lab completion time in favor of the simulation group. At the same time, the qualitative research has uncovered several issues not explored by the quantitative research. It was concluded that incorporating the recommendations acquired from the qualitative research, especially elements of incorporating hardware experience to avoid lack of hands-on skills, into the laboratory pedagogy should help improve students' experience regardless of the environment in which the laboratory is conducted.
ERIC Educational Resources Information Center
Martinez, Guadalupe; Naranjo, Francisco L.; Perez, Angel L.; Suero, Maria Isabel; Pardo, Pedro J.
2011-01-01
This study compared the educational effects of computer simulations developed in a hyper-realistic virtual environment with the educational effects of either traditional schematic simulations or a traditional optics laboratory. The virtual environment was constructed on the basis of Java applets complemented with a photorealistic visual output.…
ERIC Educational Resources Information Center
Fuson, Michael M.
2017-01-01
Laboratories studying the anisotropic rotational diffusion of bromobenzene using nuclear spin relaxation and molecular dynamics simulations are described. For many undergraduates, visualizing molecular motion is challenging. Undergraduates rarely encounter laboratories that directly assess molecular motion, and so the concept remains an…
ERIC Educational Resources Information Center
Jaakkola, T.; Nurmi, S.
2008-01-01
Computer simulations and laboratory activities have been traditionally treated as substitute or competing methods in science teaching. The aim of this experimental study was to investigate if it would be more beneficial to combine simulation and laboratory activities than to use them separately in teaching the concepts of simple electricity. Based…
Fonseca, Luciana Mara Monti; Aredes, Natália Del' Angelo; Fernandes, Ananda Maria; Batalha, Luís Manuel da Cunha; Apóstolo, Jorge Manuel Amado; Martins, José Carlos Amado; Rodrigues, Manuel Alves
2016-01-01
ABSTRACT Objectives: to evaluate the cognitive learning of nursing students in neonatal clinical evaluation from a blended course with the use of computer and laboratory simulation; to compare the cognitive learning of students in a control and experimental group testing the laboratory simulation; and to assess the extracurricular blended course offered on the clinical assessment of preterm infants, according to the students. Method: a quasi-experimental study with 14 Portuguese students, containing pretest, midterm test and post-test. The technologies offered in the course were serious game e-Baby, instructional software of semiology and semiotechnique, and laboratory simulation. Data collection tools developed for this study were used for the course evaluation and characterization of the students. Nonparametric statistics were used: Mann-Whitney and Wilcoxon. Results: the use of validated digital technologies and laboratory simulation demonstrated a statistically significant difference (p = 0.001) in the learning of the participants. The course was evaluated as very satisfactory for them. The laboratory simulation alone did not represent a significant difference in the learning. Conclusions: the cognitive learning of participants increased significantly. The use of technology can be partly responsible for the course success, showing it to be an important teaching tool for innovation and motivation of learning in healthcare. PMID:27737376
Overview of theory and simulations in the Heavy Ion Fusion Science Virtual National Laboratory
NASA Astrophysics Data System (ADS)
Friedman, Alex
2007-07-01
The Heavy Ion Fusion Science Virtual National Laboratory (HIFS-VNL) is a collaboration of Lawrence Berkeley National Laboratory, Lawrence Livermore National Laboratory, and Princeton Plasma Physics Laboratory. These laboratories, in cooperation with researchers at other institutions, are carrying out a coordinated effort to apply intense ion beams as drivers for studies of the physics of matter at extreme conditions, and ultimately for inertial fusion energy. Progress on this endeavor depends upon coordinated application of experiments, theory, and simulations. This paper describes the state of the art, with an emphasis on the coordination of modeling and experiment; developments in the simulation tools, and in the methods that underly them, are also treated.
The View of Scientific Inquiry Conveyed by Simulation-Based Virtual Laboratories
ERIC Educational Resources Information Center
Chen, Sufen
2010-01-01
With an increasing number of studies evincing the effectiveness of simulation-based virtual laboratories (VLs), researchers have discussed replacing traditional laboratories. However, the approach of doing science endorsed by VLs has not been carefully examined. A survey of 233 online VLs revealed that hypothetico-deductive (HD) logic prevails in…
ERIC Educational Resources Information Center
Yuza, Steve C.
2010-01-01
The purpose of this study was to determine the effects of interactive multimedia simulations and virtual dissection software on depth of learning among students participating in biology and chemistry laboratory courses. By understanding more about how simulation and virtual dissection software changes depth of learning, educators will have the…
A Review of Research on Technology-Assisted School Science Laboratories
ERIC Educational Resources Information Center
Wang, Chia-Yu; Wu, Hsin-Ka; Lee, Silvia Wen-Yu; Hwang, Fu-Kwun; Chang, Hsin-Yi; Wu, Ying-Tien; Chiou, Guo-Li; Chen, Sufen; Liang, Jyh-Chong; Lin, Jing-Wen; Lo, Hao-Chang; Tsai, Chin-Chung
2014-01-01
Studies that incorporate technologies into school science laboratories have proliferated in the recent two decades. A total of 42 studies published from 1990 to 2011 that incorporated technologies to support school science laboratories are reviewed here. Simulations, microcomputer-based laboratories (MBLs), and virtual laboratories are commonly…
ERIC Educational Resources Information Center
Bender, David A.
1986-01-01
Describes how a computer simulation is used with a laboratory experiment on the synthesis of urea in isolated hepatocytes. The simulation calculates the amount of urea formed and the amount of ammonium remaining as the concentrations of ornithine, citrulline, argininosuccinate, arginine, and aspartate are altered. (JN)
NASA Astrophysics Data System (ADS)
Simon, Nicole A.
Virtual laboratory experiments using interactive computer simulations are not being employed as viable alternatives to laboratory science curriculum at extensive enough rates within higher education. Rote traditional lab experiments are currently the norm and are not addressing inquiry, Critical Thinking, and cognition throughout the laboratory experience, linking with educational technologies (Pyatt & Sims, 2007; 2011; Trundle & Bell, 2010). A causal-comparative quantitative study was conducted with 150 learners enrolled at a two-year community college, to determine the effects of simulation laboratory experiments on Higher-Order Learning, Critical Thinking Skills, and Cognitive Load. The treatment population used simulated experiments, while the non-treatment sections performed traditional expository experiments. A comparison was made using the Revised Two-Factor Study Process survey, Motivated Strategies for Learning Questionnaire, and the Scientific Attitude Inventory survey, using a Repeated Measures ANOVA test for treatment or non-treatment. A main effect of simulated laboratory experiments was found for both Higher-Order Learning, [F (1, 148) = 30.32,p = 0.00, eta2 = 0.12] and Critical Thinking Skills, [F (1, 148) = 14.64,p = 0.00, eta 2 = 0.17] such that simulations showed greater increases than traditional experiments. Post-lab treatment group self-reports indicated increased marginal means (+4.86) in Higher-Order Learning and Critical Thinking Skills, compared to the non-treatment group (+4.71). Simulations also improved the scientific skills and mastery of basic scientific subject matter. It is recommended that additional research recognize that learners' Critical Thinking Skills change due to different instructional methodologies that occur throughout a semester.
Virtual and remote robotic laboratory using EJS, MATLAB and LabVIEW.
Chaos, Dictino; Chacón, Jesús; Lopez-Orozco, Jose Antonio; Dormido, Sebastián
2013-02-21
This paper describes the design and implementation of a virtual and remote laboratory based on Easy Java Simulations (EJS) and LabVIEW. The main application of this laboratory is to improve the study of sensors in Mobile Robotics, dealing with the problems that arise on the real world experiments. This laboratory allows the user to work from their homes, tele-operating a real robot that takes measurements from its sensors in order to obtain a map of its environment. In addition, the application allows interacting with a robot simulation (virtual laboratory) or with a real robot (remote laboratory), with the same simple and intuitive graphical user interface in EJS. Thus, students can develop signal processing and control algorithms for the robot in simulation and then deploy them on the real robot for testing purposes. Practical examples of application of the laboratory on the inter-University Master of Systems Engineering and Automatic Control are presented.
Virtual and Remote Robotic Laboratory Using EJS, MATLAB and Lab VIEW
Chaos, Dictino; Chacón, Jesús; Lopez-Orozco, Jose Antonio; Dormido, Sebastián
2013-01-01
This paper describes the design and implementation of a virtual and remote laboratory based on Easy Java Simulations (EJS) and LabVIEW. The main application of this laboratory is to improve the study of sensors in Mobile Robotics, dealing with the problems that arise on the real world experiments. This laboratory allows the user to work from their homes, tele-operating a real robot that takes measurements from its sensors in order to obtain a map of its environment. In addition, the application allows interacting with a robot simulation (virtual laboratory) or with a real robot (remote laboratory), with the same simple and intuitive graphical user interface in EJS. Thus, students can develop signal processing and control algorithms for the robot in simulation and then deploy them on the real robot for testing purposes. Practical examples of application of the laboratory on the inter-University Master of Systems Engineering and Automatic Control are presented. PMID:23429578
NASA Technical Reports Server (NTRS)
Taylor, B. K.; Casasent, D. P.
1989-01-01
The use of simplified error models to accurately simulate and evaluate the performance of an optical linear-algebra processor is described. The optical architecture used to perform banded matrix-vector products is reviewed, along with a linear dynamic finite-element case study. The laboratory hardware and ac-modulation technique used are presented. The individual processor error-source models and their simulator implementation are detailed. Several significant simplifications are introduced to ease the computational requirements and complexity of the simulations. The error models are verified with a laboratory implementation of the processor, and are used to evaluate its potential performance.
Computer Simulations Improve University Instructional Laboratories1
2004-01-01
Laboratory classes are commonplace and essential in biology departments but can sometimes be cumbersome, unreliable, and a drain on time and resources. As university intakes increase, pressure on budgets and staff time can often lead to reduction in practical class provision. Frequently, the ability to use laboratory equipment, mix solutions, and manipulate test animals are essential learning outcomes, and “wet” laboratory classes are thus appropriate. In others, however, interpretation and manipulation of the data are the primary learning outcomes, and here, computer-based simulations can provide a cheaper, easier, and less time- and labor-intensive alternative. We report the evaluation of two computer-based simulations of practical exercises: the first in chromosome analysis, the second in bioinformatics. Simulations can provide significant time savings to students (by a factor of four in our first case study) without affecting learning, as measured by performance in assessment. Moreover, under certain circumstances, performance can be improved by the use of simulations (by 7% in our second case study). We concluded that the introduction of these simulations can significantly enhance student learning where consideration of the learning outcomes indicates that it might be appropriate. In addition, they can offer significant benefits to teaching staff. PMID:15592599
Li, Ting; Petrini, Marcia A; Stone, Teresa E
2018-02-01
The study aim was to identify the perceived perspectives of baccalaureate nursing students toward the peer tutoring in the simulation laboratory. Insight into the nursing students' experiences and baseline data related to their perception of peer tutoring will assist to improve nursing education. Q methodology was applied to explore the students' perspectives of peer tutoring in the simulation laboratory. A convenience P-sample of 40 baccalaureate nursing students was used. Fifty-eight selected Q statements from each participant were classified into the shape of a normal distribution using an 11-point bipolar scale form with a range from -5 to +5. PQ Method software analyzed the collected data. Three discrete factors emerged: Factor I ("Facilitate or empower" knowledge acquisition), Factor II ("Safety Net" Support environment), and Factor III ("Mentoring" learn how to learn). The findings of this study support and indicate that peer tutoring is an effective supplementary strategy to promote baccalaureate students' knowledge acquisition, establishing a supportive safety net and facilitating their abilities to learn in the simulation laboratory. Copyright © 2017 Elsevier Ltd. All rights reserved.
Life sciences laboratory breadboard simulations for shuttle
NASA Technical Reports Server (NTRS)
Taketa, S. T.; Simmonds, R. C.; Callahan, P. X.
1975-01-01
Breadboard simulations of life sciences laboratory concepts for conducting bioresearch in space were undertaken as part of the concept verification testing program. Breadboard simulations were conducted to test concepts of and scope problems associated with bioresearch support equipment and facility requirements and their operational integration for conducting manned research in earth orbital missions. It emphasized requirements, functions, and procedures for candidate research on crew members (simulated) and subhuman primates and on typical radioisotope studies in rats, a rooster, and plants.
A pilot study of surgical training using a virtual robotic surgery simulator.
Tergas, Ana I; Sheth, Sangini B; Green, Isabel C; Giuntoli, Robert L; Winder, Abigail D; Fader, Amanda N
2013-01-01
Our objectives were to compare the utility of learning a suturing task on the virtual reality da Vinci Skills Simulator versus the da Vinci Surgical System dry laboratory platform and to assess user satisfaction among novice robotic surgeons. Medical trainees were enrolled prospectively; one group trained on the virtual reality simulator, and the other group trained on the da Vinci dry laboratory platform. Trainees received pretesting and post-testing on the dry laboratory platform. Participants then completed an anonymous online user experience and satisfaction survey. We enrolled 20 participants. Mean pretest completion times did not significantly differ between the 2 groups. Training with either platform was associated with a similar decrease in mean time to completion (simulator platform group, 64.9 seconds [P = .04]; dry laboratory platform group, 63.9 seconds [P < .01]). Most participants (58%) preferred the virtual reality platform. The majority found the training "definitely useful" in improving robotic surgical skills (mean, 4.6) and would attend future training sessions (mean, 4.5). Training on the virtual reality robotic simulator or the dry laboratory robotic surgery platform resulted in significant improvements in time to completion and economy of motion for novice robotic surgeons. Although there was a perception that both simulators improved performance, there was a preference for the virtual reality simulator. Benefits unique to the simulator platform include autonomy of use, computerized performance feedback, and ease of setup. These features may facilitate more efficient and sophisticated simulation training above that of the conventional dry laboratory platform, without loss of efficacy.
ERIC Educational Resources Information Center
Riaz, Muhammad
2015-01-01
The purpose of this study was to examine how simulations in physics class, class management, laboratory practice, student engagement, critical thinking, cooperative learning, and use of simulations predicted the percentage of students achieving a grade point average of B or higher and their academic performance as reported by teachers in secondary…
CRITTERS! A Realistic Simulation for Teaching Evolutionary Biology
ERIC Educational Resources Information Center
Latham, Luke G., II; Scully, Erik P.
2008-01-01
Evolutionary processes can be studied in nature and in the laboratory, but time and financial constraints result in few opportunities for undergraduate and high school students to explore the agents of genetic change in populations. One alternative to time consuming and expensive teaching laboratories is the use of computer simulations. We…
NASA Astrophysics Data System (ADS)
Choi, Byung-Soon; Gennaro, Eugene
Several researchers have suggested that the computer holds much promise as a tool for science teachers for use in their classrooms (Bork, 1979, Lunetta & Hofstein, 1981). It also has been said that there needs to be more research in determining the effectiveness of computer software (Tinker, 1983).This study compared the effectiveness of microcomputer simulated experiences with that of parallel instruction involving hands-on laboratory experiences for teaching the concept of volume displacement to junior high school students. This study also assessed the differential effect on students' understanding of the volume displacement concept using sex of the students as another independent variable. In addition, it compared the degree of retention, after 45 days, of both treatment groups.It was found that computer simulated experiences were as effective as hands-on laboratory experiences, and that males, having had hands-on laboratory experiences, performed better on the posttest than females having had the hands-on laboratory experiences. There were no significant differences in performance when comparing males with females using the computer simulation in the learning of the displacement concept. This study also showed that there were no significant differences in the retention levels when the retention scores of the computer simulation groups were compared to those that had the hands-on laboratory experiences. However, an ANOVA of the retention test scores revealed that males in both treatment conditions retained knowledge of volume displacement better than females.
System reliability of randomly vibrating structures: Computational modeling and laboratory testing
NASA Astrophysics Data System (ADS)
Sundar, V. S.; Ammanagi, S.; Manohar, C. S.
2015-09-01
The problem of determination of system reliability of randomly vibrating structures arises in many application areas of engineering. We discuss in this paper approaches based on Monte Carlo simulations and laboratory testing to tackle problems of time variant system reliability estimation. The strategy we adopt is based on the application of Girsanov's transformation to the governing stochastic differential equations which enables estimation of probability of failure with significantly reduced number of samples than what is needed in a direct simulation study. Notably, we show that the ideas from Girsanov's transformation based Monte Carlo simulations can be extended to conduct laboratory testing to assess system reliability of engineering structures with reduced number of samples and hence with reduced testing times. Illustrative examples include computational studies on a 10-degree of freedom nonlinear system model and laboratory/computational investigations on road load response of an automotive system tested on a four-post test rig.
NASA Astrophysics Data System (ADS)
Ruzhitskaya, Lanika; French, R. S.; Speck, A.
2009-05-01
We report first results from a multi-faceted study employing the lab "Revolution of the Moons of Jupiter" from the CLEA group (Contemporary Laboratory Experiences in Astronomy) in an introductory astronomy laboratory course for nonscience majors. Four laboratory sections participated in the study: two at a traditional four-year public institution in Missouri and two at a two-year community college in California. Students in all sections took identical pre- and post-tests and used the same simulation software. In all sections, students were assigned randomly to work either in pairs or individually. One section at both schools was given a brief mini-lecture on Kepler's laws and introduction to the exercise while the other section at both schools was given no instructions whatsoever. The data allow comparisons between the impact of the simulation with and without instructions and on the influences of peer interactions on learning outcomes.
Chudnoff, Scott G; Liu, Connie S; Levie, Mark D; Bernstein, Peter; Banks, Erika H
2010-09-01
To assess whether a novel educational curriculum using a simulation teaching laboratory improves resident knowledge, comfort with, and surgical performance of hysteroscopic sterilization. An educational prospective, pretest/posttest study. The Montefiore Institute of Minimally Invasive Surgery Laboratory. PATIENT(S)/SUBJECT(S): Thirty-four OB/GYN residents in an academic medical center. Hysteroscopic sterilization simulation laboratory and a brief didactic lecture. Differences in scores on validated skill assessment tools: Task specific checklist, Global Rating Scale (GRS), pass fail assessment, and a multiple-choice examination to evaluate knowledge and attitude. In the entire cohort improvements were observed on all evaluation tools after the simulation laboratory, with 31% points (SD+/-11.5, 95% confidence interval [CI] 27.3-35.3) higher score on the written evaluation; 63% points (SD+/-15.7, 95% CI 57.8-68.8) higher score on the task specific checklist; and 54% points (SD+/-13.6, 95% CI 48.8-58.3) higher score on the GRS. Higher PGY status was correlated with better pretest performance, but was not statistically significant in posttest scores. Residents reported an improvement in comfort performing the procedure after the laboratory. Simulation laboratory teaching significantly improved resident knowledge, comfort level, and technical skill performance of hysteroscopic sterilization. Copyright (c) 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Turbulence-enhanced bottom melting of a horizontal glacier--lake interface
NASA Astrophysics Data System (ADS)
Keitzl, T.; Mellado, J. P.; Notz, D.
2014-12-01
We use laboratory tank experiments and direct numerical simulations to investigate the meltrates of a horizontal bottom glacier--lake interface as a function of lake temperature. Existing parameterisations of such meltrates are usually based on empirical fits to field observations. To understand the meltrates of an ice--water interface more systematically we study an idealised system in terms of its temperature-driven buoyancy forcing. In such systems, the meltrate can be expressed analytically for a stable stratification. Here we investigate the unstable case and present how the meltrate depends on the lake temperature when the water beneath the ice is overturning and turbulent. We use laboratory tank experiments and direct numerical simulations to study an idealised ice--water boundary. The laboratory tank experiments provide robust observation-based mean-temperature profiles. The numerical simulations provide the full three-dimensional structure of the turbulent flow down to scales not accessible in the laboratory, with a minimum 0.2mm gridspacing. Our laboratory mean-temperature profiles agree well with the numerical simulations and lend credibility to our numerical setup. The structure of the turbulent flow in our simulations is well described by two self-similar subregions, a diffusion-dominated inner layer close to the ice and a turbulence-dominated outer layer far from the ice. We provide an explicit expression for the parameterisation of the meltrate of a horizontal glacier--lake interface as a function of lake temperature.
NASA Astrophysics Data System (ADS)
Zhai, Guoqing; Li, Xiaofan
2015-04-01
The Bergeron-Findeisen process has been simulated using the parameterization scheme for the depositional growth of ice crystal with the temperature-dependent theoretically predicted parameters in the past decades. Recently, Westbrook and Heymsfield (2011) calculated these parameters using the laboratory data from Takahashi and Fukuta (1988) and Takahashi et al. (1991) and found significant differences between the two parameter sets. There are two schemes that parameterize the depositional growth of ice crystal: Hsie et al. (1980), Krueger et al. (1995) and Zeng et al. (2008). In this study, we conducted three pairs of sensitivity experiments using three parameterization schemes and the two parameter sets. The pre-summer torrential rainfall event is chosen as the simulated rainfall case in this study. The analysis of root-mean-squared difference and correlation coefficient between the simulation and observation of surface rain rate shows that the experiment with the Krueger scheme and the Takahashi laboratory-derived parameters produces the best rain-rate simulation. The mean simulated rain rates are higher than the mean observational rain rate. The calculations of 5-day and model domain mean rain rates reveal that the three schemes with Takahashi laboratory-derived parameters tend to reduce the mean rain rate. The Krueger scheme together with the Takahashi laboratory-derived parameters generate the closest mean rain rate to the mean observational rain rate. The decrease in the mean rain rate caused by the Takahashi laboratory-derived parameters in the experiment with the Krueger scheme is associated with the reductions in the mean net condensation and the mean hydrometeor loss. These reductions correspond to the suppressed mean infrared radiative cooling due to the enhanced cloud ice and snow in the upper troposphere.
Process and Learning Outcomes from Remotely-Operated, Simulated, and Hands-on Student Laboratories
ERIC Educational Resources Information Center
Corter, James E.; Esche, Sven K.; Chassapis, Constantin; Ma, Jing; Nickerson, Jeffrey V.
2011-01-01
A large-scale, multi-year, randomized study compared learning activities and outcomes for hands-on, remotely-operated, and simulation-based educational laboratories in an undergraduate engineering course. Students (N = 458) worked in small-group lab teams to perform two experiments involving stress on a cantilever beam. Each team conducted the…
Thomas, Erin M; Rybski, Melinda F; Apke, Tonya L; Kegelmeyer, Deb A; Kloos, Anne D
2017-05-01
Due to the fast pace and high complexity of managing patients in intensive and acute care units (ICUs), healthcare students often feel challenged and unprepared to practice in this environment. Simulations and standardised patients provide "hands-on" learning experiences that are realistic and help students to gain competence and confidence. This study examined the impact of an intensive case simulation laboratory using a patient simulator and standardised patients on students' perceptions of their confidence and preparedness to work in acute care settings. Second-year Masters of Occupational Therapy (MOT; n = 127) and Doctor of Physical Therapy (DPT; n = 105) students participated in a three-hour intensive care simulation laboratory comprised of four stations that were designed to simulate common ICU patient care scenarios. Data analysed were student pre- and post-simulation surveys and written comments, and clinical instructors' (CIs; n = 51) ratings on DPT students' preparedness and confidence within the first two weeks of their acute care internships obtained after the laboratory. There was a significant increase for DPT (p < 0.0001) and MOT (p < 0.10) students in median ratings of how prepared they felt to practice in acute care settings following the ICU simulation compared to before the laboratory. CIs rated the DPT students as either prepared or very prepared for and moderately confident or very confident in the acute care setting. The use of simulation training using standardised patients and patient simulators was beneficial in increasing student confidence and preparing OT and PT students to practice in the acute care setting. Health professional educators should consider using an interprofessional simulation experience to improve their students' confidence and preparedness to provide appropriate care in the acute setting.
"I got it on Ebay!": cost-effective approach to surgical skills laboratories.
Schneider, Ethan; Schenarts, Paul J; Shostrom, Valerie; Schenarts, Kimberly D; Evans, Charity H
2017-01-01
Surgical education is witnessing a surge in the use of simulation. However, implementation of simulation is often cost-prohibitive. Online shopping offers a low budget alternative. The aim of this study was to implement cost-effective skills laboratories and analyze online versus manufacturers' prices to evaluate for savings. Four skills laboratories were designed for the surgery clerkship from July 2014 to June 2015. Skills laboratories were implemented using hand-built simulation and instruments purchased online. Trademarked simulation was priced online and instruments priced from a manufacturer. Costs were compiled, and a descriptive cost analysis of online and manufacturers' prices was performed. Learners rated their level of satisfaction for all educational activities, and levels of satisfaction were compared. A total of 119 third-year medical students participated. Supply lists and costs were compiled for each laboratory. A descriptive cost analysis of online and manufacturers' prices showed online prices were substantially lower than manufacturers, with a per laboratory savings of: $1779.26 (suturing), $1752.52 (chest tube), $2448.52 (anastomosis), and $1891.64 (laparoscopic), resulting in a year 1 savings of $47,285. Mean student satisfaction scores for the skills laboratories were 4.32, with statistical significance compared to live lectures at 2.96 (P < 0.05) and small group activities at 3.67 (P < 0.05). A cost-effective approach for implementation of skills laboratories showed substantial savings. By using hand-built simulation boxes and online resources to purchase surgical equipment, surgical educators overcome financial obstacles limiting the use of simulation and provide learning opportunities that medical students perceive as beneficial. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Collinson, Glyn A.; Dorelli, John Charles; Avanov, Leon A.; Lewis, Gethyn R.; Moore, Thomas E.; Pollock, Craig; Kataria, Dhiren O.; Bedington, Robert; Arridge, Chris S.; Chornay, Dennis J.;
2012-01-01
We report our findings comparing the geometric factor (GF) as determined from simulations and laboratory measurements of the new Dual Electron Spectrometer (DES) being developed at NASA Goddard Space Flight Center as part of the Fast Plasma Investigation on NASA's Magnetospheric Multiscale mission. Particle simulations are increasingly playing an essential role in the design and calibration of electrostatic analyzers, facilitating the identification and mitigation of the many sources of systematic error present in laboratory calibration. While equations for laboratory measurement of the Geometric Factpr (GF) have been described in the literature, these are not directly applicable to simulation since the two are carried out under substantially different assumptions and conditions, making direct comparison very challenging. Starting from first principles, we derive generalized expressions for the determination of the GF in simulation and laboratory, and discuss how we have estimated errors in both cases. Finally, we apply these equations to the new DES instrument and show that the results agree within errors. Thus we show that the techniques presented here will produce consistent results between laboratory and simulation, and present the first description of the performance of the new DES instrument in the literature.
A system dynamics approach to analyze laboratory test errors.
Guo, Shijing; Roudsari, Abdul; Garcez, Artur d'Avila
2015-01-01
Although many researches have been carried out to analyze laboratory test errors during the last decade, it still lacks a systemic view of study, especially to trace errors during test process and evaluate potential interventions. This study implements system dynamics modeling into laboratory errors to trace the laboratory error flows and to simulate the system behaviors while changing internal variable values. The change of the variables may reflect a change in demand or a proposed intervention. A review of literature on laboratory test errors was given and provided as the main data source for the system dynamics model. Three "what if" scenarios were selected for testing the model. System behaviors were observed and compared under different scenarios over a period of time. The results suggest system dynamics modeling has potential effectiveness of helping to understand laboratory errors, observe model behaviours, and provide a risk-free simulation experiments for possible strategies.
NASA Technical Reports Server (NTRS)
Horst, Richard L.; Mahaffey, David L.; Munson, Robert C.
1989-01-01
The present Phase 2 small business innovation research study was designed to address issues related to scalp-recorded event-related potential (ERP) indices of mental workload and to transition this technology from the laboratory to cockpit simulator environments for use as a systems engineering tool. The project involved five main tasks: (1) Two laboratory studies confirmed the generality of the ERP indices of workload obtained in the Phase 1 study and revealed two additional ERP components related to workload. (2) A task analysis' of flight scenarios and pilot tasks in the Advanced Concepts Flight Simulator (ACFS) defined cockpit events (i.e., displays, messages, alarms) that would be expected to elicit ERPs related to workload. (3) Software was developed to support ERP data analysis. An existing ARD-proprietary package of ERP data analysis routines was upgraded, new graphics routines were developed to enhance interactive data analysis, and routines were developed to compare alternative single-trial analysis techniques using simulated ERP data. (4) Working in conjunction with NASA Langley research scientists and simulator engineers, preparations were made for an ACFS validation study of ERP measures of workload. (5) A design specification was developed for a general purpose, computerized, workload assessment system that can function in simulators such as the ACFS.
NASA Technical Reports Server (NTRS)
Steffes, Paul G.
1987-01-01
Laboratory measurements were conducted to evaluate properties of atmospheric gases under simulated conditions for the outer planets. A significant addition to this effort was the capability to make such measurements at millimeter wavelengths. Measurements should soon be completed on the millimeter wave absorption from ammonia under Jovian conditions. Also studied will be the feasibility of measuring the microwave and millimeter wave properties of phosphine (PH3) under simulated Jovian conditions. Further analysis and application of the laboratory results to microwave and millimeter wave absorption data for the outer planet, such as Voyager Radio Occultation experiments, will be pursued.
Galactic cosmic ray simulation at the NASA Space Radiation Laboratory
Norbury, John W.; Schimmerling, Walter; Slaba, Tony C.; Azzam, Edouard I.; Badavi, Francis F.; Baiocco, Giorgio; Benton, Eric; Bindi, Veronica; Blakely, Eleanor A.; Blattnig, Steve R.; Boothman, David A.; Borak, Thomas B.; Britten, Richard A.; Curtis, Stan; Dingfelder, Michael; Durante, Marco; Dynan, William S.; Eisch, Amelia J.; Elgart, S. Robin; Goodhead, Dudley T.; Guida, Peter M.; Heilbronn, Lawrence H.; Hellweg, Christine E.; Huff, Janice L.; Kronenberg, Amy; La Tessa, Chiara; Lowenstein, Derek I.; Miller, Jack; Morita, Takashi; Narici, Livio; Nelson, Gregory A.; Norman, Ryan B.; Ottolenghi, Andrea; Patel, Zarana S.; Reitz, Guenther; Rusek, Adam; Schreurs, Ann-Sofie; Scott-Carnell, Lisa A.; Semones, Edward; Shay, Jerry W.; Shurshakov, Vyacheslav A.; Sihver, Lembit; Simonsen, Lisa C.; Story, Michael D.; Turker, Mitchell S.; Uchihori, Yukio; Williams, Jacqueline; Zeitlin, Cary J.
2017-01-01
Most accelerator-based space radiation experiments have been performed with single ion beams at fixed energies. However, the space radiation environment consists of a wide variety of ion species with a continuous range of energies. Due to recent developments in beam switching technology implemented at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL), it is now possible to rapidly switch ion species and energies, allowing for the possibility to more realistically simulate the actual radiation environment found in space. The present paper discusses a variety of issues related to implementation of galactic cosmic ray (GCR) simulation at NSRL, especially for experiments in radiobiology. Advantages and disadvantages of different approaches to developing a GCR simulator are presented. In addition, issues common to both GCR simulation and single beam experiments are compared to issues unique to GCR simulation studies. A set of conclusions is presented as well as a discussion of the technical implementation of GCR simulation. PMID:26948012
Galactic cosmic ray simulation at the NASA Space Radiation Laboratory.
Norbury, John W; Schimmerling, Walter; Slaba, Tony C; Azzam, Edouard I; Badavi, Francis F; Baiocco, Giorgio; Benton, Eric; Bindi, Veronica; Blakely, Eleanor A; Blattnig, Steve R; Boothman, David A; Borak, Thomas B; Britten, Richard A; Curtis, Stan; Dingfelder, Michael; Durante, Marco; Dynan, William S; Eisch, Amelia J; Robin Elgart, S; Goodhead, Dudley T; Guida, Peter M; Heilbronn, Lawrence H; Hellweg, Christine E; Huff, Janice L; Kronenberg, Amy; La Tessa, Chiara; Lowenstein, Derek I; Miller, Jack; Morita, Takashi; Narici, Livio; Nelson, Gregory A; Norman, Ryan B; Ottolenghi, Andrea; Patel, Zarana S; Reitz, Guenther; Rusek, Adam; Schreurs, Ann-Sofie; Scott-Carnell, Lisa A; Semones, Edward; Shay, Jerry W; Shurshakov, Vyacheslav A; Sihver, Lembit; Simonsen, Lisa C; Story, Michael D; Turker, Mitchell S; Uchihori, Yukio; Williams, Jacqueline; Zeitlin, Cary J
2016-02-01
Most accelerator-based space radiation experiments have been performed with single ion beams at fixed energies. However, the space radiation environment consists of a wide variety of ion species with a continuous range of energies. Due to recent developments in beam switching technology implemented at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL), it is now possible to rapidly switch ion species and energies, allowing for the possibility to more realistically simulate the actual radiation environment found in space. The present paper discusses a variety of issues related to implementation of galactic cosmic ray (GCR) simulation at NSRL, especially for experiments in radiobiology. Advantages and disadvantages of different approaches to developing a GCR simulator are presented. In addition, issues common to both GCR simulation and single beam experiments are compared to issues unique to GCR simulation studies. A set of conclusions is presented as well as a discussion of the technical implementation of GCR simulation. Published by Elsevier Ltd.
Sticking properties of ice grains
NASA Astrophysics Data System (ADS)
Jongmanns, M.; Kumm, M.; Wurm, G.; Wolf, D. E.; Teiser, J.
2017-06-01
We study the size dependence of pull-off forces of water ice in laboratory experiments and numerical simulations. To determine the pull-off force in our laboratory experiments, we use a liquid nitrogen cooled centrifuge. Depending on its rotation frequency, spherical ice grains detach due to the centrifugal force which is related to the adhesive properties. Numerical simulations are conducted by means of molecular dynamics simulations of hexagonal ice using a standard coarse-grained water potential. The pull-off force of a single contact between two spherical ice grains is measured due to strain controlled simulations. Both, the experimental study and the simulations reveal a dependence between the pull-off force and the (reduced) particle radii, which differ significantly from the linear dependence of common contact theories.
Onoue, Satomi; Hosoi, Kazuhiro; Toda, Tsuguto; Takagi, Hironori; Osaki, Naoto; Matsumoto, Yasuhiro; Kawakami, Satoru; Wakuri, Shinobu; Iwase, Yumiko; Yamamoto, Toshinobu; Nakamura, Kazuichi; Ohno, Yasuo; Kojima, Hajime
2014-06-01
A previous multi-center validation study demonstrated high transferability and reliability of reactive oxygen species (ROS) assay for photosafety evaluation. The present validation study was undertaken to verify further the applicability of different solar simulators and assay performance. In 7 participating laboratories, 2 standards and 42 coded chemicals, including 23 phototoxins and 19 non-phototoxic drugs/chemicals, were assessed by the ROS assay using two different solar simulators (Atlas Suntest CPS series, 3 labs; and Seric SXL-2500V2, 4 labs). Irradiation conditions could be optimized using quinine and sulisobenzone as positive and negative standards to offer consistent assay outcomes. In both solar simulators, the intra- and inter-day precisions (coefficient of variation; CV) for quinine were found to be below 10%. The inter-laboratory CV for quinine averaged 15.4% (Atlas Suntest CPS) and 13.2% (Seric SXL-2500V2) for singlet oxygen and 17.0% (Atlas Suntest CPS) and 7.1% (Seric SXL-2500V2) for superoxide, suggesting high inter-laboratory reproducibility even though different solar simulators were employed for the ROS assay. In the ROS assay on 42 coded chemicals, some chemicals (ca. 19-29%) were unevaluable because of limited solubility and spectral interference. Although several false positives appeared with positive predictivity of ca. 76-92% (Atlas Suntest CPS) and ca. 75-84% (Seric SXL-2500V2), there were no false negative predictions in both solar simulators. A multi-center validation study on the ROS assay demonstrated satisfactory transferability, accuracy, precision, and predictivity, as well as the availability of other solar simulators. Copyright © 2013 Elsevier Ltd. All rights reserved.
NETL Extreme Drilling Laboratory Studies High Pressure High Temperature Drilling Phenomena
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lyons, K.D.; Honeygan, S.; Moroz, T.H.
2008-12-01
The U.S. Department of Energy's National Energy Technology Laboratory (NETL) established the Extreme Drilling Laboratory to engineer effective and efficient drilling technologies viable at depths greater than 20,000 ft. This paper details the challenges of ultradeep drilling, documents reports of decreased drilling rates as a result of increasing fluid pressure and temperature, and describes NETL's research and development activities. NETL is invested in laboratory-scale physical simulation. Its physical simulator will have capability of circulating drilling fluids at 30,000 psi and 480°F around a single drill cutter. This simulator is not yet operational; therefore, the results will be limited to themore » identification of leading hypotheses of drilling phenomena and NETL's test plans to validate or refute such theories. Of particular interest to the Extreme Drilling Laboratory's studies are the combinatorial effects of drilling fluid pressure, drilling fluid properties, rock properties, pore pressure, and drilling parameters, such as cutter rotational speed, weight on bit, and hydraulics associated with drilling fluid introduction to the rock-cutter interface. A detailed discussion of how each variable is controlled in a laboratory setting will be part of the conference paper and presentation.« less
NASA Technical Reports Server (NTRS)
Steffes, Paul G.
1991-01-01
Laboratory measurements of microwave and millimeter wave properties of the simulated atmosphere of the outer planets and their satellites has continued. One of the focuses is on the development of a radiative transfer model of the Jovian atmosphere at wavelengths from 1 mm to 10 cm. This modeling effort led to laboratory measurements of the millimeter wave opacity of hydrogen sulfide (H2S) under simulated Jovian conditions. Descriptions of the modeling effort, the Laboratory experiment, and the observations are presented. Correlative studies of measurements with Pioneer-Venus radio occultation measurements with longer wavelength emission measurements have provided new ways for characterizing temporal and spatial variations in the abundance of both gases H2SO4 and SO2, and for modeling their roles in the subcloud atmosphere. Laboratory measurements were conducted on 1.35 cm (and 13 cm) opacity of gaseous SO2 and absorptivity of gaseous SO2 at the 3.2 mm wavelength under simulated Venus conditions. Laboratory measurements were completed on millimeter wave dielectric properties of liquid H2SO4, in order to model the effects of the opacity of the clouds of Venus onto millimeter wave emission spectrum.
Computational simulation of laboratory-scale volcanic jets
NASA Astrophysics Data System (ADS)
Solovitz, S.; Van Eaton, A. R.; Mastin, L. G.; Herzog, M.
2017-12-01
Volcanic eruptions produce ash clouds that may travel great distances, significantly impacting aviation and communities downwind. Atmospheric hazard forecasting relies partly on numerical models of the flow physics, which incorporate data from eruption observations and analogue laboratory tests. As numerical tools continue to increase in complexity, they must be validated to fine-tune their effectiveness. Since eruptions are relatively infrequent and challenging to observe in great detail, analogue experiments can provide important insights into expected behavior over a wide range of input conditions. Unfortunately, laboratory-scale jets cannot easily attain the high Reynolds numbers ( 109) of natural volcanic eruption columns. Comparisons between the computational models and analogue experiments can help bridge this gap. In this study, we investigate a 3-D volcanic plume model, the Active Tracer High-resolution Atmospheric Model (ATHAM), which has been used to simulate a variety of eruptions. However, it has not been previously validated using laboratory-scale data. We conducted numerical simulations of three flows that we have studied in the laboratory: a vertical jet in a quiescent environment, a vertical jet in horizontal cross flow, and a particle-laden jet. We considered Reynolds numbers from 10,000 to 50,000, jet-to-cross flow velocity ratios of 2 to 10, and particle mass loadings of up to 25% of the exit mass flow rate. Vertical jet simulations produce Gaussian velocity profiles in the near exit region by 3 diameters downstream, matching the mean experimental profiles. Simulations of air entrainment are of the correct order of magnitude, but they show decreasing entrainment with vertical distance from the vent. Cross flow simulations reproduce experimental trajectories for the jet centerline initially, although confinement appears to impact the response later. Particle-laden simulations display minimal variation in concentration profiles between cases with different mass loadings and size distributions, indicating that differences in particle behavior may not be evident at this laboratory scale.
ERIC Educational Resources Information Center
Dyrberg, Nadia Rahbek; Treusch, Alexander H.; Wiegand, Claudia
2017-01-01
Potential benefits of simulations and virtual laboratory exercises in natural sciences have been both theorised and studied recently. This study reports findings from a pilot study on student attitude, motivation and self-efficacy when using the virtual laboratory programme Labster. The programme allows interactive learning about the workflows and…
Moreno-Ger, Pablo; Torrente, Javier; Bustamante, Julián; Fernández-Galaz, Carmen; Fernández-Manjón, Baltasar; Comas-Rengifo, María Dolores
2010-06-01
Practical sessions in undergraduate medical education are often costly and have to face constraints in terms of available laboratory time and practice materials (e.g. blood samples from animals). This makes it difficult to increase the time each student spends at the laboratory. We consider that it would be possible to improve the effectiveness of the laboratory time by providing the students with computer-based simulations for prior rehearsal. However, this approach still presents issues in terms of development costs and distribution to the students. This study investigates the employment of low-cost simulation to allow medical students to rehearse practical exercises through a web-based e-learning environment. The aim is to maximize the efficiency of laboratory time and resources allocated by letting students become familiarized with the equipment and the procedures before they attend a laboratory session, but without requiring large-scale investment. Moreover, students can access the simulation via the Internet and rehearse at their own pace. We have studied the effects of such a simulation in terms of impact on the laboratory session, learning outcomes and student satisfaction. We created a simulation that covers the steps of a practical exercise in a Physiology course (measuring hematocrit in a blood sample). An experimental group (EG, n=66) played the simulation 1 week before the laboratory session. A control group (CG, n=77) attended the laboratory session without playing the simulation. After the session, all students completed a survey about their perception of the difficulty of the exercise on a scale of 1-10 and the HCT final value that they obtained. The students in the EG also completed a survey about their satisfaction with the experience. After the laboratory session, the perceived difficulty of the procedure was lower on average in the EG compared to the CG (3.52 vs. 4.39, 95% CI: 0.16-1.57, P=.016). There was no significant difference in terms of perceived difficulty using the equipment. The HCT measures reported by the EG group also presented a much lower dispersion, meaning a higher reliability, in determining the HCT value (3.10 vs. 26.94, SD; variances significantly different, P<.001, F: 75.25, Dfd: 68.19 for EG and CG). In the satisfaction test, the majority of the students in the EG reported that the experience was positive or very positive (80.7%) and reported that it had helped them to identify and use the equipment (78%) and to perform the exercise (66%). The simulation was well received by students in the EG, who felt more comfortable during the laboratory session, and it helped them to perform the exercise better, obtaining more accurate results, which indicates more effective training. EG students perceived the procedure as easier to perform, but did not report an improvement in the perceived difficulty in using the equipment. The increased reliability demonstrates that low-cost simulations are a good complement to the laboratory sessions. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.
Simulations of Highway Traffic With Various Degrees of Automation
DOT National Transportation Integrated Search
1996-01-01
A traffic simulator to study highway traffic under various degrees of automation is being developed at Argonne National Laboratory. The key components of this simulator include a global and a local Expert Driver Model, a human factor study and a grap...
NASA Astrophysics Data System (ADS)
Shegog, Ross; Lazarus, Melanie M.; Murray, Nancy G.; Diamond, Pamela M.; Sessions, Nathalie; Zsigmond, Eva
2012-10-01
The transgenic mouse model is useful for studying the causes and potential cures for human genetic diseases. Exposing high school biology students to laboratory experience in developing transgenic animal models is logistically prohibitive. Computer-based simulation, however, offers this potential in addition to advantages of fidelity and reach. This study describes and evaluates a computer-based simulation to train advanced placement high school science students in laboratory protocols, a transgenic mouse model was produced. A simulation module on preparing a gene construct in the molecular biology lab was evaluated using a randomized clinical control design with advanced placement high school biology students in Mercedes, Texas ( n = 44). Pre-post tests assessed procedural and declarative knowledge, time on task, attitudes toward computers for learning and towards science careers. Students who used the simulation increased their procedural and declarative knowledge regarding molecular biology compared to those in the control condition (both p < 0.005). Significant increases continued to occur with additional use of the simulation ( p < 0.001). Students in the treatment group became more positive toward using computers for learning ( p < 0.001). The simulation did not significantly affect attitudes toward science in general. Computer simulation of complex transgenic protocols have potential to provide a "virtual" laboratory experience as an adjunct to conventional educational approaches.
Does a surgical simulator improve resident operative performance of laparoscopic tubal ligation?
Banks, Erika H; Chudnoff, Scott; Karmin, Ira; Wang, Cuiling; Pardanani, Setul
2007-11-01
The purpose of this study was to assess whether a surgical skills simulator laboratory improves resident knowledge and operative performance of laparoscopic tubal ligation. Twenty postgraduate year 1 residents were assigned randomly to either a surgical simulator laboratory on laparoscopic tubal ligation together with apprenticeship teaching in the operating room or to apprenticeship teaching alone. Tests that were given before and after the training assessed basic knowledge. Attending physicians who were blinded to resident randomization status evaluated postgraduate year 1 performance on a laparoscopic tubal ligation in the operating room with 3 validated tools: a task-specific checklist, global rating scale, and pass/fail grade. Postgraduate year 1 residents who were assigned randomly to the surgical simulator laboratory performed significantly better than control subjects on all 3 surgical assessment tools (the checklist, the global score, and the pass/fail analysis) and scored significantly better on the knowledge posttest (all P < .0005). Compared with apprenticeship teaching alone, a surgical simulator laboratory on laparoscopic tubal ligation improved resident knowledge and performance in the operating room.
Annotated Bibliography of USAARL Technical and Letter Reports. Volume 2. October 1988 - April 1991
1991-05-01
G. Lilienthal, Robert S. Kennedy, Jennifer E. Fowlkes, and Dennis R. Baltzley. As technelogy has been developed to provide improved visual and motion...Gower, Jr., and Jennifer Fowlkes. The U.S. Army Aeromedical Research Laboratory conducted field studies of operational flight simulators to assess the...Daniel W. Gower, Jr., and Jennifer Fowlkes. The U.S. Army Aeromedical Research Laboratory conducted field studies of operational flight simulators to
Concept Verification Test - Evaluation of Spacelab/Payload operation concepts
NASA Technical Reports Server (NTRS)
Mcbrayer, R. O.; Watters, H. H.
1977-01-01
The Concept Verification Test (CVT) procedure is used to study Spacelab operational concepts by conducting mission simulations in a General Purpose Laboratory (GPL) which represents a possible design of Spacelab. In conjunction with the laboratory a Mission Development Simulator, a Data Management System Simulator, a Spacelab Simulator, and Shuttle Interface Simulator have been designed. (The Spacelab Simulator is more functionally and physically representative of the Spacelab than the GPL.) Four simulations of Spacelab mission experimentation were performed, two involving several scientific disciplines, one involving life sciences, and the last involving material sciences. The purpose of the CVT project is to support the pre-design and development of payload carriers and payloads, and to coordinate hardware, software, and operational concepts of different developers and users.
Shetty, Shohan; Zevin, Boris; Grantcharov, Teodor P; Roberts, Kurt E; Duffy, Andrew J
2014-01-01
Simulation training for surgical residents can shorten learning curves, improve technical skills, and expedite competency. Several studies have shown that skills learned in the simulated environment are transferable to the operating room. Residency programs are trying to incorporate simulation into the resident training curriculum to supplement the hands-on experience gained in the operating room. Despite the availability and proven utility of surgical simulators and simulation laboratories, they are still widely underutilized by surgical trainees. Studies have shown that voluntary use leads to minimal participation in a training curriculum. Although there are several simulation tools, there is no clear evidence of the superiority of one tool over the other in skill acquisition. The purpose of this study was to explore resident perceptions, training experiences, and preferences regarding laparoscopic simulation training. Our goal was to profile resident participation in surgical skills simulation, recognize potential barriers to voluntary simulator use, and identify simulation tools and tasks preferred by residents. Furthermore, this study may help to inform whether mandatory/protected training time, as part of the residents' curriculum is essential to enhance participation in the simulation laboratory. A cross-sectional study on general surgery residents (postgraduate years 1-5) at Yale University School of Medicine and the University of Toronto via an online questionnaire was conducted. Overall, 67 residents completed the survey. The institutional review board approved the methods of the study. Overall, 95.5% of the participants believed that simulation training improved their laparoscopic skills. Most respondents (92.5%) perceived that skills learned during simulation training were transferrable to the operating room. Overall, 56.7% of participants agreed that proficiency in a simulation curriculum should be mandatory before operating room experience. The simulation laboratory was most commonly used during work hours; lack of free time during work hours was most commonly cited as a reason for underutilization. Factors influencing use of the simulation laboratory in order of importance were the need for skill development, an interest in minimally invasive surgery, mandatory/protected time in a simulation environment as part of the residency program curriculum, a recommendation by an attending surgeon, and proximity of the simulation center. The most preferred simulation tool was the live animal model followed by cadaveric tissue. Virtual reality simulators were among the least-preferred (25%) simulation tools. Most residents (91.0%) felt that mandatory/protected time in a simulation environment should be introduced into resident training protocols. Mandatory and protected time in a simulation environment as part of the resident training curriculum may improve participation in simulation training. A comprehensive curriculum, which includes the use of live animals, cadaveric tissue, and virtual reality simulators, may enhance the laparoscopic training experience and interest level of surgical trainees. Copyright © 2014 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
Yuan, Haomin; Solberg, Jerome; Merzari, Elia; ...
2017-08-01
This study describes a numerical study of flow-induced vibration in a helical coil steam generator experiment conducted at Argonne National Laboratory in the 1980 s. In the experiment, a half-scale sector model of a steam generator helical coil tube bank was subjected to still and flowing air and water, and the vibrational characteristics were recorded. The research detailed in this document utilizes the multi-physics simulation toolkit SHARP developed at Argonne National Laboratory, in cooperation with Lawrence Livermore National Laboratory, to simulate the experiment. SHARP uses the spectral element code Nek5000 for fluid dynamics analysis and the finite element code DIABLOmore » for structural analysis. The flow around the coil tubes is modeled in Nek5000 by using a large eddy simulation turbulence model. Transient pressure data on the tube surfaces is sampled and transferred to DIABLO for the structural simulation. The structural response is simulated in DIABLO via an implicit time-marching algorithm and a combination of continuum elements and structural shells. Tube vibration data (acceleration and frequency) are sampled and compared with the experimental data. Currently, only one-way coupling is used, which means that pressure loads from the fluid simulation are transferred to the structural simulation but the resulting structural displacements are not fed back to the fluid simulation.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yuan, Haomin; Solberg, Jerome; Merzari, Elia
This study describes a numerical study of flow-induced vibration in a helical coil steam generator experiment conducted at Argonne National Laboratory in the 1980 s. In the experiment, a half-scale sector model of a steam generator helical coil tube bank was subjected to still and flowing air and water, and the vibrational characteristics were recorded. The research detailed in this document utilizes the multi-physics simulation toolkit SHARP developed at Argonne National Laboratory, in cooperation with Lawrence Livermore National Laboratory, to simulate the experiment. SHARP uses the spectral element code Nek5000 for fluid dynamics analysis and the finite element code DIABLOmore » for structural analysis. The flow around the coil tubes is modeled in Nek5000 by using a large eddy simulation turbulence model. Transient pressure data on the tube surfaces is sampled and transferred to DIABLO for the structural simulation. The structural response is simulated in DIABLO via an implicit time-marching algorithm and a combination of continuum elements and structural shells. Tube vibration data (acceleration and frequency) are sampled and compared with the experimental data. Currently, only one-way coupling is used, which means that pressure loads from the fluid simulation are transferred to the structural simulation but the resulting structural displacements are not fed back to the fluid simulation.« less
Using a Laboratory Simulator in the Teaching and Study of Chemical Processes in Estuarine Systems
ERIC Educational Resources Information Center
Garcia-Luque, E.; Ortega, T.; Forja, J. M.; Gomez-Parra, A.
2004-01-01
The teaching of Chemical Oceanography in the Faculty of Marine and Environmental Sciences of the University of Cadiz (Spain) has been improved since 1994 by the employment of a device for the laboratory simulation of estuarine mixing processes and the characterisation of the chemical behaviour of many substances that pass through an estuary. The…
ERIC Educational Resources Information Center
Unlu, Zeynep Koyunlu; Dokme, Ibilge
2011-01-01
The purpose of this study was to investigate whether the combination of both analogy-based simulation and laboratory activities as a teaching tool was more effective than utilizing them separately in teaching the concepts of simple electricity. The quasi-experimental design that involved 66 seventh grade students from urban Turkish elementary…
Development of space simulation / net-laboratory system
NASA Astrophysics Data System (ADS)
Usui, H.; Matsumoto, H.; Ogino, T.; Fujimoto, M.; Omura, Y.; Okada, M.; Ueda, H. O.; Murata, T.; Kamide, Y.; Shinagawa, H.; Watanabe, S.; Machida, S.; Hada, T.
A research project for the development of space simulation / net-laboratory system was approved by Japan Science and Technology Corporation (JST) in the category of Research and Development for Applying Advanced Computational Science and Technology(ACT-JST) in 2000. This research project, which continues for three years, is a collaboration with an astrophysical simulation group as well as other space simulation groups which use MHD and hybrid models. In this project, we develop a proto type of unique simulation system which enables us to perform simulation runs by providing or selecting plasma parameters through Web-based interface on the internet. We are also developing an on-line database system for space simulation from which we will be able to search and extract various information such as simulation method and program, manuals, and typical simulation results in graphic or ascii format. This unique system will help the simulation beginners to start simulation study without much difficulty or effort, and contribute to the promotion of simulation studies in the STP field. In this presentation, we will report the overview and the current status of the project.
A Novel Simulation Technician Laboratory Design: Results of a Survey-Based Study
Hughes, Patrick G; Friedl, Ed; Ortiz Figueroa, Fabiana; Cepeda Brito, Jose R; Frey, Jennifer; Birmingham, Lauren E; Atkinson, Steven Scott
2016-01-01
Objective The purpose of this study was to elicit feedback from simulation technicians prior to developing the first simulation technician-specific simulation laboratory in Akron, OH. Background Simulation technicians serve a vital role in simulation centers within hospitals/health centers around the world. The first simulation technician degree program in the US has been approved in Akron, OH. To satisfy the requirements of this program and to meet the needs of this special audience of learners, a customized simulation lab is essential. Method A web-based survey was circulated to simulation technicians prior to completion of the lab for the new program. The survey consisted of questions aimed at identifying structural and functional design elements of a novel simulation center for the training of simulation technicians. Quantitative methods were utilized to analyze data. Results Over 90% of technicians (n=65) think that a lab designed explicitly for the training of technicians is novel and beneficial. Approximately 75% of respondents think that the space provided appropriate audiovisual (AV) infrastructure and space to evaluate the ability of technicians to be independent. The respondents think that the lab needed more storage space, visualization space for a large number of students, and more space in the technical/repair area. Conclusions A space designed for the training of simulation technicians was considered to be beneficial. This laboratory requires distinct space for technical repair, adequate bench space for the maintenance and repair of simulators, an appropriate AV infrastructure, and space to evaluate the ability of technicians to be independent. PMID:27096134
A Novel Simulation Technician Laboratory Design: Results of a Survey-Based Study.
Ahmed, Rami; Hughes, Patrick G; Friedl, Ed; Ortiz Figueroa, Fabiana; Cepeda Brito, Jose R; Frey, Jennifer; Birmingham, Lauren E; Atkinson, Steven Scott
2016-03-16
OBJECTIVE : The purpose of this study was to elicit feedback from simulation technicians prior to developing the first simulation technician-specific simulation laboratory in Akron, OH. Simulation technicians serve a vital role in simulation centers within hospitals/health centers around the world. The first simulation technician degree program in the US has been approved in Akron, OH. To satisfy the requirements of this program and to meet the needs of this special audience of learners, a customized simulation lab is essential. A web-based survey was circulated to simulation technicians prior to completion of the lab for the new program. The survey consisted of questions aimed at identifying structural and functional design elements of a novel simulation center for the training of simulation technicians. Quantitative methods were utilized to analyze data. Over 90% of technicians (n=65) think that a lab designed explicitly for the training of technicians is novel and beneficial. Approximately 75% of respondents think that the space provided appropriate audiovisual (AV) infrastructure and space to evaluate the ability of technicians to be independent. The respondents think that the lab needed more storage space, visualization space for a large number of students, and more space in the technical/repair area. CONCLUSIONS : A space designed for the training of simulation technicians was considered to be beneficial. This laboratory requires distinct space for technical repair, adequate bench space for the maintenance and repair of simulators, an appropriate AV infrastructure, and space to evaluate the ability of technicians to be independent.
Simulating Astrophysical Jets with Inertial Confinement Fusion Machines
NASA Astrophysics Data System (ADS)
Blue, Brent
2005-10-01
Large-scale directional outflows of supersonic plasma, also known as `jets', are ubiquitous phenomena in astrophysics. The traditional approach to understanding such phenomena is through theoretical analysis and numerical simulations. However, theoretical analysis might not capture all the relevant physics and numerical simulations have limited resolution and fail to scale correctly in Reynolds number and perhaps other key dimensionless parameters. Recent advances in high energy density physics using large inertial confinement fusion devices now allow controlled laboratory experiments on macroscopic volumes of plasma of direct relevance to astrophysics. This talk will present an overview of these facilities as well as results from current laboratory astrophysics experiments designed to study hydrodynamic jets and Rayleigh-Taylor mixing. This work is performed under the auspices of the U. S. DOE by Lawrence Livermore National Laboratory under Contract No. W-7405-ENG-48, Los Alamos National Laboratory under Contract No. W-7405-ENG-36, and the Laboratory for Laser Energetics under Contract No. DE-FC03-92SF19460.
Brooks, M.H.; Schroder, L.J.; Malo, B.A.
1985-01-01
Four laboratories were evaluated in their analysis of identical natural and simulated precipitation water samples. Interlaboratory comparability was evaluated using analysis of variance coupled with Duncan 's multiple range test, and linear-regression models describing the relations between individual laboratory analytical results for natural precipitation samples. Results of the statistical analyses indicate that certain pairs of laboratories produce different results when analyzing identical samples. Analyte bias for each laboratory was examined using analysis of variance coupled with Duncan 's multiple range test on data produced by the laboratories from the analysis of identical simulated precipitation samples. Bias for a given analyte produced by a single laboratory has been indicated when the laboratory mean for that analyte is shown to be significantly different from the mean for the most-probable analyte concentrations in the simulated precipitation samples. Ion-chromatographic methods for the determination of chloride, nitrate, and sulfate have been compared with the colorimetric methods that were also in use during the study period. Comparisons were made using analysis of variance coupled with Duncan 's multiple range test for means produced by the two methods. Analyte precision for each laboratory has been estimated by calculating a pooled variance for each analyte. Analyte estimated precisions have been compared using F-tests and differences in analyte precisions for laboratory pairs have been reported. (USGS)
ERIC Educational Resources Information Center
Bradway, Heather A.
2001-01-01
Explains a laboratory activity in which students study the effects of balanced and unbalanced nutrition on individuals' health by examining simulated urine samples. Uses a journal writing approach and includes laboratory instructions. (YDS)
Dual Arm Work Package performance estimates and telerobot task network simulation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Draper, J.V.; Blair, L.M.
1997-02-01
This paper describes the methodology and results of a network simulation study of the Dual Arm Work Package (DAWP), to be employed for dismantling the Argonne National Laboratory CP-5 reactor. The development of the simulation model was based upon the results of a task analysis for the same system. This study was performed by the Oak Ridge National Laboratory (ORNL), in the Robotics and Process Systems Division. Funding was provided the US Department of Energy`s Office of Technology Development, Robotics Technology Development Program (RTDP). The RTDP is developing methods of computer simulation to estimate telerobotic system performance. Data were collectedmore » to provide point estimates to be used in a task network simulation model. Three skilled operators performed six repetitions of a pipe cutting task representative of typical teleoperation cutting operations.« less
Simulating direct shear tests with the Bullet physics library: A validation study.
Izadi, Ehsan; Bezuijen, Adam
2018-01-01
This study focuses on the possible uses of physics engines, and more specifically the Bullet physics library, to simulate granular systems. Physics engines are employed extensively in the video gaming, animation and movie industries to create physically plausible scenes. They are designed to deliver a fast, stable, and optimal simulation of certain systems such as rigid bodies, soft bodies and fluids. This study focuses exclusively on simulating granular media in the context of rigid body dynamics with the Bullet physics library. The first step was to validate the results of the simulations of direct shear testing on uniform-sized metal beads on the basis of laboratory experiments. The difference in the average angle of mobilized frictions was found to be only 1.0°. In addition, a very close match was found between dilatancy in the laboratory samples and in the simulations. A comprehensive study was then conducted to determine the failure and post-failure mechanism. We conclude with the presentation of a simulation of a direct shear test on real soil which demonstrated that Bullet has all the capabilities needed to be used as software for simulating granular systems.
NASA Technical Reports Server (NTRS)
1993-01-01
A description is given of each of the following Langley research and test facilities: 0.3-Meter Transonic Cryogenic Tunnel, 7-by 10-Foot High Speed Tunnel, 8-Foot Transonic Pressure Tunnel, 13-Inch Magnetic Suspension & Balance System, 14-by 22-Foot Subsonic Tunnel, 16-Foot Transonic Tunnel, 16-by 24-Inch Water Tunnel, 20-Foot Vertical Spin Tunnel, 30-by 60-Foot Wind Tunnel, Advanced Civil Transport Simulator (ACTS), Advanced Technology Research Laboratory, Aerospace Controls Research Laboratory (ACRL), Aerothermal Loads Complex, Aircraft Landing Dynamics Facility (ALDF), Avionics Integration Research Laboratory, Basic Aerodynamics Research Tunnel (BART), Compact Range Test Facility, Differential Maneuvering Simulator (DMS), Enhanced/Synthetic Vision & Spatial Displays Laboratory, Experimental Test Range (ETR) Flight Research Facility, General Aviation Simulator (GAS), High Intensity Radiated Fields Facility, Human Engineering Methods Laboratory, Hypersonic Facilities Complex, Impact Dynamics Research Facility, Jet Noise Laboratory & Anechoic Jet Facility, Light Alloy Laboratory, Low Frequency Antenna Test Facility, Low Turbulence Pressure Tunnel, Mechanics of Metals Laboratory, National Transonic Facility (NTF), NDE Research Laboratory, Polymers & Composites Laboratory, Pyrotechnic Test Facility, Quiet Flow Facility, Robotics Facilities, Scientific Visualization System, Scramjet Test Complex, Space Materials Research Laboratory, Space Simulation & Environmental Test Complex, Structural Dynamics Research Laboratory, Structural Dynamics Test Beds, Structures & Materials Research Laboratory, Supersonic Low Disturbance Pilot Tunnel, Thermal Acoustic Fatigue Apparatus (TAFA), Transonic Dynamics Tunnel (TDT), Transport Systems Research Vehicle, Unitary Plan Wind Tunnel, and the Visual Motion Simulator (VMS).
NASA Technical Reports Server (NTRS)
Norbury, John W.; Slaba, Tony C.; Rusek, Adam; Durante, Marco; Reitz, Guenther
2015-01-01
An international collaboration on Galactic Cosmic Ray (GCR) simulation is being formed to make recommendations on how to best simulate the GCR spectrum at ground based accelerators. The external GCR spectrum is significantly modified when it passes through spacecraft shielding and astronauts. One approach for simulating the GCR space radiation environment at ground based accelerators would use the modified spectrum, rather than the external spectrum, in the accelerator beams impinging on biological targets. Two recent workshops have studied such GCR simulation. The first workshop was held at NASA Langley Research Center in October 2014. The second workshop was held at the NASA Space Radiation Investigators' workshop in Galveston, Texas in January 2015. The anticipated outcome of these and other studies may be a report or journal article, written by an international collaboration, making accelerator beam recommendations for GCR simulation. This poster describes the status of GCR simulation at the NASA Space Radiation Laboratory and encourages others to join the collaboration.
An Educational Laboratory for Digital Control and Rapid Prototyping of Power Electronic Circuits
ERIC Educational Resources Information Center
Choi, Sanghun; Saeedifard, M.
2012-01-01
This paper describes a new educational power electronics laboratory that was developed primarily to reinforce experimentally the fundamental concepts presented in a power electronics course. The developed laboratory combines theoretical design, simulation studies, digital control, fabrication, and verification of power-electronic circuits based on…
Best, Virginia; Keidser, Gitte; Buchholz, J(x004E7)rg M.; Freeston, Katrina
2016-01-01
Objective There is increasing demand in the hearing research community for the creation of laboratory environments that better simulate challenging real-world listening environments. The hope is that the use of such environments for testing will lead to more meaningful assessments of listening ability, and better predictions about the performance of hearing devices. Here we present one approach for simulating a complex acoustic environment in the laboratory, and investigate the effect of transplanting a speech test into such an environment. Design Speech reception thresholds were measured in a simulated reverberant cafeteria, and in a more typical anechoic laboratory environment containing background speech babble. Study Sample The participants were 46 listeners varying in age and hearing levels, including 25 hearing-aid wearers who were tested with and without their hearing aids. Results Reliable SRTs were obtained in the complex environment, but led to different estimates of performance and hearing aid benefit from those measured in the standard environment. Conclusions The findings provide a starting point for future efforts to increase the real-world relevance of laboratory-based speech tests. PMID:25853616
Laboratory evaluation of the pointing stability of the ASPS Vernier System
NASA Technical Reports Server (NTRS)
1980-01-01
The annular suspension and pointing system (ASPS) is an end-mount experiment pointing system designed for use in the space shuttle. The results of the ASPS Vernier System (AVS) pointing stability tests conducted in a laboratory environment are documented. A simulated zero-G suspension was used to support the test payload in the laboratory. The AVS and the suspension were modelled and incorporated into a simulation of the laboratory test. Error sources were identified and pointing stability sensitivities were determined via simulation. Statistical predictions of laboratory test performance were derived and compared to actual laboratory test results. The predicted mean pointing stability during simulated shuttle disturbances was 1.22 arc seconds; the actual mean laboratory test pointing stability was 1.36 arc seconds. The successful prediction of laboratory test results provides increased confidence in the analytical understanding of the AVS magnetic bearing technology and allows confident prediction of in-flight performance. Computer simulations of ASPS, operating in the shuttle disturbance environment, predict in-flight pointing stability errors less than 0.01 arc seconds.
NASA Technical Reports Server (NTRS)
Salama, Farid
2014-01-01
We present and discuss the unique characteristics and capabilities of the laboratory facility, COSmIC, that was developed at NASA Ames to generate, process and analyze interstellar, circumstellar and planetary analogs in the laboratory. COSmIC stands for Cosmic Simulation Chamber and is dedicated to the study of molecules and ions under the low temperature and high vacuum conditions that are required to simulate interstellar, circumstellar and planetary physical environments in space. COSmIC integrates a variety of state-of-the-art instruments that allow forming, processing and monitoring simulated space conditions for planetary, circumstellar and interstellar materials in the laboratory. COSmIC is composed of a Pulsed Discharge Nozzle (PDN) expansion that generates a free jet supersonic expansion coupled to two ultrahigh-sensitivity, complementary in situ diagnostics: a Cavity Ring Down Spectroscopy (CRDS) system for photonic detection and a Reflectron Time-Of-Flight Mass Spectrometer (ReTOF-MS) for mass detection. Recent, unique, laboratory astrophysics results that were obtained using the capabilities of COSmIC will be discussed, in particular the progress that have been achieved in monitoring in the laboratory the formation of solid gains from their gas-phase molecular precursors in environments as varied as stellar/circumstellar outflow and planetary atmospheres. Plans for future, next generation, laboratory experiments on cosmic molecules and grains in the growing field of laboratory astrophysics will also be addressed as well as the implications of these studies for current and upcoming space missions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thoma, C.; Welch, D. R.; Hsu, S. C.
2013-08-15
We describe numerical simulations, using the particle-in-cell (PIC) and hybrid-PIC code lsp[T. P. Hughes et al., Phys. Rev. ST Accel. Beams 2, 110401 (1999)], of the head-on merging of two laboratory supersonic plasma jets. The goals of these experiments are to form and study astrophysically relevant collisionless shocks in the laboratory. Using the plasma jet initial conditions (density ∼10{sup 14}–10{sup 16} cm{sup −3}, temperature ∼ few eV, and propagation speed ∼20–150 km/s), large-scale simulations of jet propagation demonstrate that interactions between the two jets are essentially collisionless at the merge region. In highly resolved one- and two-dimensional simulations, we showmore » that collisionless shocks are generated by the merging jets when immersed in applied magnetic fields (B∼0.1–1 T). At expected plasma jet speeds of up to 150 km/s, our simulations do not give rise to unmagnetized collisionless shocks, which require much higher velocities. The orientation of the magnetic field and the axial and transverse density gradients of the jets have a strong effect on the nature of the interaction. We compare some of our simulation results with those of previously published PIC simulation studies of collisionless shock formation.« less
Cultural Norms of Clinical Simulation in Undergraduate Nursing Education
2015-01-01
Simulated practice of clinical skills has occurred in skills laboratories for generations, and there is strong evidence to support high-fidelity clinical simulation as an effective tool for learning performance-based skills. What are less known are the processes within clinical simulation environments that facilitate the learning of socially bound and integrated components of nursing practice. Our purpose in this study was to ethnographically describe the situated learning within a simulation laboratory for baccalaureate nursing students within the western United States. We gathered and analyzed data from observations of simulation sessions as well as interviews with students and faculty to produce a rich contextualization of the relationships, beliefs, practices, environmental factors, and theoretical underpinnings encoded in cultural norms of the students’ situated practice within simulation. Our findings add to the evidence linking learning in simulation to the development of broad practice-based skills and clinical reasoning for undergraduate nursing students. PMID:28462300
The optimization of total laboratory automation by simulation of a pull-strategy.
Yang, Taho; Wang, Teng-Kuan; Li, Vincent C; Su, Chia-Lo
2015-01-01
Laboratory results are essential for physicians to diagnose medical conditions. Because of the critical role of medical laboratories, an increasing number of hospitals use total laboratory automation (TLA) to improve laboratory performance. Although the benefits of TLA are well documented, systems occasionally become congested, particularly when hospitals face peak demand. This study optimizes TLA operations. Firstly, value stream mapping (VSM) is used to identify the non-value-added time. Subsequently, batch processing control and parallel scheduling rules are devised and a pull mechanism that comprises a constant work-in-process (CONWIP) is proposed. Simulation optimization is then used to optimize the design parameters and to ensure a small inventory and a shorter average cycle time (CT). For empirical illustration, this approach is applied to a real case. The proposed methodology significantly improves the efficiency of laboratory work and leads to a reduction in patient waiting times and increased service level.
NASA Technical Reports Server (NTRS)
Stevens, N. J.
1979-01-01
Cases where the charged-particle environment acts on the spacecraft (e.g., spacecraft charging phenomena) and cases where a system on the spacecraft causes the interaction (e.g., high voltage space power systems) are considered. Both categories were studied in ground simulation facilities to understand the processes involved and to measure the pertinent parameters. Computer simulations are based on the NASA Charging Analyzer Program (NASCAP) code. Analytical models are developed in this code and verified against the experimental data. Extrapolation from the small test samples to space conditions are made with this code. Typical results from laboratory and computer simulations are presented for both types of interactions. Extrapolations from these simulations to performance in space environments are discussed.
Simulation and measurement of melting effects on metal sheets caused by direct lightning strikes
NASA Technical Reports Server (NTRS)
Kern, Alexander
1991-01-01
Direct lightning strikes melt metal parts of various systems, like fuel and propellant tanks of rockets and airplanes, at the point of strike. Responsible for this melting are the impulse current and, if occurring, the long duration current, both carrying a remarkable charge Q. For studying these meltings the simulation in the laboratory has to be based on the parameters of natural lightnings. International standards exist defining certain threat levels of natural lightnings and giving possible generator circuits for the simulation. The melting caused by both types of lightning currents show different appearance. Their characteristics, their differences in melting and heating of metal sheets are investigated. Nevertheless the simulation of lightning in the laboratory is imperfect. While natural lightning is a discharge without a counter electrode, the simulation always demands a close counter electrode. The influence of this counter electrode is studied.
NASA Astrophysics Data System (ADS)
Danáčová, Michaela; Valent, Peter; Výleta, Roman
2017-12-01
Nowadays, rainfall simulators are being used by many researchers in field or laboratory experiments. The main objective of most of these experiments is to better understand the underlying runoff generation processes, and to use the results in the process of calibration and validation of hydrological models. Many research groups have assembled their own rainfall simulators, which comply with their understanding of rainfall processes, and the requirements of their experiments. Most often, the existing rainfall simulators differ mainly in the size of the irrigated area, and the way they generate rain drops. They can be characterized by the accuracy, with which they produce a rainfall of a given intensity, the size of the irrigated area, and the rain drop generating mechanism. Rainfall simulation experiments can provide valuable information about the genesis of surface runoff, infiltration of water into soil and rainfall erodibility. Apart from the impact of physical properties of soil, its moisture and compaction on the generation of surface runoff and the amount of eroded particles, some studies also investigate the impact of vegetation cover of the whole area of interest. In this study, the rainfall simulator was used to simulate the impact of the slope gradient of the irrigated area on the amount of generated runoff and sediment yield. In order to eliminate the impact of external factors and to improve the reproducibility of the initial conditions, the experiments were conducted in laboratory conditions. The laboratory experiments were carried out using a commercial rainfall simulator, which was connected to an external peristaltic pump. The pump maintained a constant and adjustable inflow of water, which enabled to overcome the maximum volume of simulated precipitation of 2.3 l, given by the construction of the rainfall simulator, while maintaining constant characteristics of the simulated precipitation. In this study a 12-minute rainfall with a constant intensity of 5 mm/min was used to irrigate a corrupted soil sample. The experiment was undertaken for several different slopes, under the condition of no vegetation cover. The results of the rainfall simulation experiment complied with the expectations of a strong relationship between the slope gradient, and the amount of surface runoff generated. The experiments with higher slope gradients were characterised by larger volumes of surface runoff generated, and by shorter times after which it occurred. The experiments with rainfall simulators in both laboratory and field conditions play an important role in better understanding of runoff generation processes. The results of such small scale experiments could be used to estimate some of the parameters of complex hydrological models, which are used to model rainfall-runoff and erosion processes at catchment scale.
The Virtual Radiopharmacy Laboratory: A 3-D Simulation for Distance Learning
ERIC Educational Resources Information Center
Alexiou, Antonios; Bouras, Christos; Giannaka, Eri; Kapoulas, Vaggelis; Nani, Maria; Tsiatsos, Thrasivoulos
2004-01-01
This article presents Virtual Radiopharmacy Laboratory (VR LAB), a virtual laboratory accessible through the Internet. VR LAB is designed and implemented in the framework of the VirRAD European project. This laboratory represents a 3D simulation of a radio-pharmacy laboratory, where learners, represented by 3D avatars, can experiment on…
NASA Astrophysics Data System (ADS)
Balakrishnan, B.; Woods, P. C.
2013-05-01
Over the years, rapid development in computer technology has engendered simulation-based laboratory (lab) in addition to the traditional hands-on (physical) lab. Many higher education institutions adopt simulation lab, replacing some existing physical lab experiments. The creation of new systems for conducting engineering lab activities has raised concerns among educators on the merits and shortcomings of both physical and simulation labs; at the same time, many arguments have been raised on the differences of both labs. Investigating the effectiveness of both labs is complicated, as there are multiple factors that should be considered. In view of this challenge, a study on students' perspectives on their experience related to key aspects on engineering laboratory exercise was conducted. In this study, the Visual Auditory Read and Kinetic model was utilised to measure the students' cognitive styles. The investigation was done through a survey among participants from Multimedia University, Malaysia. The findings revealed that there are significant differences for most of the aspects in physical and simulation labs.
High-fidelity nursing simulation: impact on student self-confidence and clinical competence.
Blum, Cynthia A; Borglund, Susan; Parcells, Dax
2010-01-01
Development of safe nursing practice in entry-level nursing students requires special consideration from nurse educators. The paucity of data supporting high-fidelity patient simulation effectiveness in this population informed the development of a quasi-experimental, quantitative study of the relationship between simulation and student self-confidence and clinical competence. Moreover, the study reports a novel approach to measuring self-confidence and competence of entry-level nursing students. Fifty-three baccalaureate students, enrolled in either a traditional or simulation-enhanced laboratory, participated during their first clinical rotation. Student self-confidence and faculty perception of student clinical competence were measured using selected scale items of the Lasater Clinical Judgment Rubric. The results indicated an overall improvement in self-confidence and competence across the semester, however, simulation did not significantly enhance these caring attributes. The study highlights the need for further examination of teaching strategies developed to promote the transfer of self-confidence and competence from the laboratory to the clinical setting.
Computer Based Simulation of Laboratory Experiments.
ERIC Educational Resources Information Center
Edward, Norrie S.
1997-01-01
Examines computer based simulations of practical laboratory experiments in engineering. Discusses the aims and achievements of lab work (cognitive, process, psychomotor, and affective); types of simulations (model building and behavioral); and the strengths and weaknesses of simulations. Describes the development of a centrifugal pump simulation,…
Study of an instrument for sensing errors in a telescope wavefront
NASA Technical Reports Server (NTRS)
Golden, L. J.; Shack, R. V.; Slater, P. N.
1974-01-01
Focal plane sensors for determining the error in a telescope wavefront were investigated. The construction of three candidate test instruments and their evaluation in terms of small wavefront error aberration measurements are described. A laboratory wavefront simulator was designed and fabricated to evaluate the test instruments. The laboratory wavefront error simulator was used to evaluate three tests; a Hartmann test, a polarization shearing interferometer test, and an interferometric Zernike test.
Experiments in pilot decision-making during simulated low visibility approaches
NASA Technical Reports Server (NTRS)
Curry, R. E.; Lauber, J. K.; Billings, C. E.
1975-01-01
A simulation task is reported which incorporates both kinds of variables, informational and psychological, to successfully study pilot decision making behavior in the laboratory. Preliminary experiments in the measurement of decisions and the inducement of stress in simulated low visibility approaches are described.
Laboratory study of sonic booms and their scaling laws. [ballistic range simulation
NASA Technical Reports Server (NTRS)
Toong, T. Y.
1974-01-01
This program undertook to seek a basic understanding of non-linear effects associated with caustics, through laboratory simulation experiments of sonic booms in a ballistic range and a coordinated theoretical study of scaling laws. Two cases of superbooms or enhanced sonic booms at caustics have been studied. The first case, referred to as acceleration superbooms, is related to the enhanced sonic booms generated during the acceleration maneuvers of supersonic aircrafts. The second case, referred to as refraction superbooms, involves the superbooms that are generated as a result of atmospheric refraction. Important theoretical and experimental results are briefly reported.
Human cadavers Vs. multimedia simulation: A study of student learning in anatomy.
Saltarelli, Andrew J; Roseth, Cary J; Saltarelli, William A
2014-01-01
Multimedia and simulation programs are increasingly being used for anatomy instruction, yet it remains unclear how learning with these technologies compares with learning with actual human cadavers. Using a multilevel, quasi-experimental-control design, this study compared the effects of "Anatomy and Physiology Revealed" (APR) multimedia learning system with a traditional undergraduate human cadaver laboratory. APR is a model-based multimedia simulation tool that uses high-resolution pictures to construct a prosected cadaver. APR also provides animations showing the function of specific anatomical structures. Results showed that the human cadaver laboratory offered a significant advantage over the multimedia simulation program on cadaver-based measures of identification and explanatory knowledge. These findings reinforce concerns that incorporating multimedia simulation into anatomy instruction requires careful alignment between learning tasks and performance measures. Findings also imply that additional pedagogical strategies are needed to support transfer from simulated to real-world application of anatomical knowledge. © 2014 American Association of Anatomists.
NASA Astrophysics Data System (ADS)
van den Ende, M. P. A.; Chen, J.; Ampuero, J.-P.; Niemeijer, A. R.
2018-05-01
Rate-and-state friction (RSF) is commonly used for the characterisation of laboratory friction experiments, such as velocity-step tests. However, the RSF framework provides little physical basis for the extrapolation of these results to the scales and conditions of natural fault systems, and so open questions remain regarding the applicability of the experimentally obtained RSF parameters for predicting seismic cycle transients. As an alternative to classical RSF, microphysics-based models offer means for interpreting laboratory and field observations, but are generally over-simplified with respect to heterogeneous natural systems. In order to bridge the temporal and spatial gap between the laboratory and nature, we have implemented existing microphysical model formulations into an earthquake cycle simulator. Through this numerical framework, we make a direct comparison between simulations exhibiting RSF-controlled fault rheology, and simulations in which the fault rheology is dictated by the microphysical model. Even though the input parameters for the RSF simulation are directly derived from the microphysical model, the microphysics-based simulations produce significantly smaller seismic event sizes than the RSF-based simulation, and suggest a more stable fault slip behaviour. Our results reveal fundamental limitations in using classical rate-and-state friction for the extrapolation of laboratory results. The microphysics-based approach offers a more complete framework in this respect, and may be used for a more detailed study of the seismic cycle in relation to material properties and fault zone pressure-temperature conditions.
ERIC Educational Resources Information Center
Edward, Norrie S.
1997-01-01
Evaluates the importance of realism in the screen presentation of the plant in computer-based laboratory simulations for part-time engineering students. Concludes that simulations are less effective than actual laboratories but that realism minimizes the disadvantages. The schematic approach was preferred for ease of use. (AIM)
DHM and serious games: a case-study oil and gas laboratories.
Santos, V; Zamberlan, M; Streit, P; Oliveira, J; Guimarães, C; Pastura, F; Cid, G
2012-01-01
The aim in this paper is to present a research on the application of serious games for the design of laboratories in the oil and gas industries. The focus is in human virtual representation acquired from 3D scanning, human interaction, workspace layout and equipment designed considering ergonomics standards. The laboratory studies were simulated in Unity3D platform, which allows the users to control the DHM1 on the dynamic virtual scenario, in order to simulate work activities. This methodology can change the design process by improving the level of interaction between final users, managers and human factor teams. That helps to better visualize future work settings and improve the level of participation between all stakeholders.
ERIC Educational Resources Information Center
Jaakkola, Tomi; Nurmi, Sami; Veermans, Koen
2011-01-01
The aim of this experimental study was to compare learning outcomes of students using a simulation alone (simulation environment) with outcomes of those using a simulation in parallel with real circuits (combination environment) in the domain of electricity, and to explore how learning outcomes in these environments are mediated by implicit (only…
ERIC Educational Resources Information Center
Frey, E. Ramsey; Sygula, Andrzej; Hammer, Nathan I.
2014-01-01
This laboratory exercise introduces undergraduate chemistry majors to the spectroscopic and theoretical study of the polycyclic aromatic hydrocarbon (PAH), corannulene. Students explore the spectroscopic properties of corannulene using UV-vis and Raman vibrational spectroscopies. They compare their experimental results to simulated vibrational…
HYDRAULIC CHARACTERISTICS OF SEWER SEDIMENT GATE FLUSHING TANKS: LABORATORY FLUME STUDIES
The objective of this study was to test the performance of gate flushing tanks, simulated in a laboratory flume, to remove sediments from combined sewers and storage tanks. A significant amount of sediment/debris/sludge may accumulate at the bottom of a sewer during dry weather o...
Nanomaterials are increasingly being used in polymer composites to enhance the properties of these materials. Here we present results of a pilot inter-laboratory study to simulate the effects of weathering on the potential release of multiwalled carbon nanotubes (MWCNT) from thei...
HYDRAULIC CHARACTERISTICS OF SEWER SEDIMENT GATE-FLUSHING TANKS: LABORATORY FLUME STUDIES
The objective of this study was to test the performance of gate-flushing tanks, simulated in a laboratory flume, to remove sediments from combined sewers and storage tanks. A significant amount of sediment/debris/sludge may accumulate at the bottom of a sewer during dry weather o...
SEWER SEDIMENT GATE AND VACUUM FLUSHING TANKS: LABORATORY FLUME STUDIES
The objective of this study was to test the performance of a traditional gate-flushing device and a newly designed vacuum-flushing device in removing sediments from combined sewers and CSO storage tanks. A laboratory hydraulic flune was used to simulate a reach of sewer or storag...
Simulation studies for the evaluation of health information technologies: experiences and results.
Ammenwerth, Elske; Hackl, Werner O; Binzer, Kristine; Christoffersen, Tue E H; Jensen, Sanne; Lawton, Kitta; Skjoet, Peter; Nohr, Christian
It is essential for new health information technologies (IT) to undergo rigorous evaluations to ensure they are effective and safe for use in real-world situations. However, evaluation of new health IT is challenging, as field studies are often not feasible when the technology being evaluated is not sufficiently mature. Laboratory-based evaluations have also been shown to have insufficient external validity. Simulation studies seem to be a way to bridge this gap. The aim of this study was to evaluate, using a simulation methodology, the impact of a new prototype of an electronic medication management system on the appropriateness of prescriptions and drug-related activities, including laboratory test ordering or medication changes. This article presents the results of a controlled simulation study with 50 simulation runs, including ten doctors and five simulation patients, and discusses experiences and lessons learnt while conducting the study. Although the new electronic medication management system showed tendencies to improve medication safety when compared with the standard system, this tendency was not significant. Altogether, five distinct situations were identified where the new medication management system did help to improve medication safety. This simulation study provided a good compromise between internal validity and external validity. However, several challenges need to be addressed when undertaking simulation evaluations including: preparation of adequate test cases; training of participants before using unfamiliar applications; consideration of time, effort and costs of conducting the simulation; technical maturity of the evaluated system; and allowing adequate preparation of simulation scenarios and simulation setting. Simulation studies are an interesting but time-consuming approach, which can be used to evaluate newly developed health IT systems, particularly those systems that are not yet sufficiently mature to undergo field evaluation studies.
Sundler, Annelie J; Pettersson, Annika; Berglund, Mia
2015-12-01
Simulation has become a widely used and established pedagogy for teaching clinical nursing skills. Nevertheless, the evidence in favour of this pedagogical approach is weak, and more knowledge is needed in support of its use. The aim of this study was (a) to explore the experiences of undergraduate nursing students when examining knowledge, skills and competences in clinical simulation laboratories with high-fidelity patient simulators and (b) to analyse these students' learning experiences during the examination. A phenomenological approach was used, and qualitative interviews were conducted among 23 second-year undergraduate nursing students-17 women and 6 men. The findings revealed that, irrespective of whether they passed or failed the examination, it was experienced as a valuable assessment of the students' knowledge and skills. Even if the students felt that the examination was challenging, they described it as a learning opportunity. In the examination, the students were able to integrate theory with practice, and earlier established knowledge was scrutinised when reflecting on the scenarios. The examination added aspects to the students' learning that prepared them for the real world of nursing in a safe environment without risking patient safety. The study findings suggest that examinations in clinical simulation laboratories can be a useful teaching strategy in nursing education. The use of high-fidelity patient simulators made the examination authentic. The reflections and feedback on the scenario were described as significant for the students' learning. Undergraduate nursing students can improve their knowledge, understanding, competence and skills when such examinations are performed in the manner used in this study. Copyright © 2015 Elsevier Ltd. All rights reserved.
Validation of Dissolution Testing with Biorelevant Media: An OrBiTo Study.
Mann, James; Dressman, Jennifer; Rosenblatt, Karin; Ashworth, Lee; Muenster, Uwe; Frank, Kerstin; Hutchins, Paul; Williams, James; Klumpp, Lukas; Wielockx, Kristina; Berben, Philippe; Augustijns, Patrick; Holm, Rene; Hofmann, Michael; Patel, Sanjaykumar; Beato, Stefania; Ojala, Krista; Tomaszewska, Irena; Bruel, Jean-Luc; Butler, James
2017-12-04
Dissolution testing with biorelevant media has become widespread in the pharmaceutical industry as a means of better understanding how drugs and formulations behave in the gastrointestinal tract. Until now, however, there have been few attempts to gauge the reproducibility of results obtained with these methods. The aim of this study was to determine the interlaboratory reproducibility of biorelevant dissolution testing, using the paddle apparatus (USP 2). Thirteen industrial and three academic laboratories participated in this study. All laboratories were provided with standard protocols for running the tests: dissolution in FaSSGF to simulate release in the stomach, dissolution in a single intestinal medium, FaSSIF, to simulate release in the small intestine, and a "transfer" (two-stage) protocol to simulate the concentration profile when conditions are changed from the gastric to the intestinal environment. The test products chosen were commercially available ibuprofen tablets and zafirlukast tablets. The biorelevant dissolution tests showed a high degree of reproducibility among the participating laboratories, even though several different batches of the commercially available medium preparation powder were used. Likewise, results were almost identicalbetween the commercial biorelevant media and those produced in-house. Comparing results to previous ring studies, including those performed with USP calibrator tablets or commercially available pharmaceutical products in a single medium, the results for the biorelevant studies were highly reproducible on an interlaboratory basis. Interlaboratory reproducibility with the two-stage test was also acceptable, although the variability was somewhat greater than with the single medium tests. Biorelevant dissolution testing is highly reproducible among laboratories and can be relied upon for cross-laboratory comparisons.
Simulated Laboratory in Digital Logic.
ERIC Educational Resources Information Center
Cleaver, Thomas G.
Design of computer circuits used to be a pencil and paper task followed by laboratory tests, but logic circuit design can now be done in half the time as the engineer accesses a program which simulates the behavior of real digital circuits, and does all the wiring and testing on his computer screen. A simulated laboratory in digital logic has been…
Human System Simulation in Support of Human Performance Technical Basis at NPPs
DOE Office of Scientific and Technical Information (OSTI.GOV)
David Gertman; Katya Le Blanc; alan mecham
2010-06-01
This paper focuses on strategies and progress toward establishing the Idaho National Laboratory’s (INL’s) Human Systems Simulator Laboratory at the Center for Advanced Energy Studies (CAES), a consortium of Idaho State Universities. The INL is one of the National Laboratories of the US Department of Energy. One of the first planned applications for the Human Systems Simulator Laboratory is implementation of a dynamic nuclear power plant simulation (NPP) where studies of operator workload, situation awareness, performance and preference will be carried out in simulated control rooms including nuclear power plant control rooms. Simulation offers a means by which to reviewmore » operational concepts, improve design practices and provide a technical basis for licensing decisions. In preparation for the next generation power plant and current government and industry efforts in support of light water reactor sustainability, human operators will be attached to a suite of physiological measurement instruments and, in combination with traditional Human Factors Measurement techniques, carry out control room tasks in simulated advanced digital and hybrid analog/digital control rooms. The current focus of the Human Systems Simulator Laboratory is building core competence in quantitative and qualitative measurements of situation awareness and workload. Of particular interest is whether introduction of digital systems including automated procedures has the potential to reduce workload and enhance safety while improving situation awareness or whether workload is merely shifted and situation awareness is modified in yet to be determined ways. Data analysis is carried out by engineers and scientists and includes measures of the physical and neurological correlates of human performance. The current approach supports a user-centered design philosophy (see ISO 13407 “Human Centered Design Process for Interactive Systems, 1999) wherein the context for task performance along with the requirements of the end-user are taken into account during the design process and the validity of design is determined through testing of real end users« less
The flight robotics laboratory
NASA Technical Reports Server (NTRS)
Tobbe, Patrick A.; Williamson, Marlin J.; Glaese, John R.
1988-01-01
The Flight Robotics Laboratory of the Marshall Space Flight Center is described in detail. This facility, containing an eight degree of freedom manipulator, precision air bearing floor, teleoperated motion base, reconfigurable operator's console, and VAX 11/750 computer system, provides simulation capability to study human/system interactions of remote systems. The facility hardware, software and subsequent integration of these components into a real time man-in-the-loop simulation for the evaluation of spacecraft contact proximity and dynamics are described.
Fried, Ronna; Surman, Craig; Hammerness, Paul; Petty, Carter; Faraone, Stephen; Hyder, Laran; Westerberg, Diana; Small, Jacqueline; Corkum, Lyndsey; Claudat, Kim; Biederman, Joseph
2012-12-30
Despite an extant literature documenting that adults with attention-deficit/hyperactivity disorder (ADHD) are at increased risk for significant difficulties in the workplace, there is little documentation of the underlying factors associated with these impairments. The main aim of this study was to examine specific deficiencies associated with ADHD on workplace performance in a simulated workplace laboratory relative to controls. Participants were 56 non-medicated young adults with DSM-IV ADHD and 63 age- and sex-matched controls without ADHD. Participants spent 10h in a workplace simulation laboratory. Areas assessed included: (1) simulated tasks documented in a government report (SCANS) often required in workplace settings (taxing vigilance; planning; cooperation; attention to detail), (2) observer ratings, and (3) self-reports. Robust findings were found in the statistically significant differences on self-report of ADHD symptoms found between participants with ADHD and controls during all workplace tasks and periods of the workday. Task performance was found to be deficient in a small number of areas, and there were a few statistically significant differences identified by observer ratings. Symptoms reported by participants with ADHD in the simulation including internal restlessness, intolerance of boredom and difficulty maintaining vigilance were significant and could adversely impact workplace performance over the long-term. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yuan, Haomin; Solberg, Jerome; Merzari, Elia
This paper describes a numerical study of flow-induced vibration in a helical coil steam generator experiment conducted at Argonne National Laboratory in the 1980s. In the experiment, a half-scale sector model of a steam generator helical coil tube bank was subjected to still and flowing air and water, and the vibrational characteristics were recorded. The research detailed in this document utilizes the multi-physics simulation toolkit SHARP developed at Argonne National Laboratory, in cooperation with Lawrence Livermore National Laboratory, to simulate the experiment. SHARP uses the spectral element code Nek5000 for fluid dynamics analysis and the finite element code DIABLO formore » structural analysis. The flow around the coil tubes is modeled in Nek5000 by using a large eddy simulation turbulence model. Transient pressure data on the tube surfaces is sampled and transferred to DIABLO for the structural simulation. The structural response is simulated in DIABLO via an implicit time-marching algorithm and a combination of continuum elements and structural shells. Tube vibration data (acceleration and frequency) are sampled and compared with the experimental data. Currently, only one-way coupling is used, which means that pressure loads from the fluid simulation are transferred to the structural simulation but the resulting structural displacements are not fed back to the fluid simulation« less
ERIC Educational Resources Information Center
Waddick, John
1994-01-01
Compares the effect of a chemistry computer simulation, written by the author, with the effect of an instructor demonstration. The study indicates that in this particular situation the operation of a spectrophotometer can be effectively taught by computer simulation method. The program is written using HyperTalk, the HyperCard programming…
NASA Astrophysics Data System (ADS)
Schirmer, Mario; Molson, John W.; Frind, Emil O.; Barker, James F.
2000-12-01
Biodegradation of organic contaminants in groundwater is a microscale process which is often observed on scales of 100s of metres or larger. Unfortunately, there are no known equivalent parameters for characterizing the biodegradation process at the macroscale as there are, for example, in the case of hydrodynamic dispersion. Zero- and first-order degradation rates estimated at the laboratory scale by model fitting generally overpredict the rate of biodegradation when applied to the field scale because limited electron acceptor availability and microbial growth are not considered. On the other hand, field-estimated zero- and first-order rates are often not suitable for predicting plume development because they may oversimplify or neglect several key field scale processes, phenomena and characteristics. This study uses the numerical model BIO3D to link the laboratory and field scales by applying laboratory-derived Monod kinetic degradation parameters to simulate a dissolved gasoline field experiment at the Canadian Forces Base (CFB) Borden. All input parameters were derived from independent laboratory and field measurements or taken from the literature a priori to the simulations. The simulated results match the experimental results reasonably well without model calibration. A sensitivity analysis on the most uncertain input parameters showed only a minor influence on the simulation results. Furthermore, it is shown that the flow field, the amount of electron acceptor (oxygen) available, and the Monod kinetic parameters have a significant influence on the simulated results. It is concluded that laboratory-derived Monod kinetic parameters can adequately describe field scale degradation, provided all controlling factors are incorporated in the field scale model. These factors include advective-dispersive transport of multiple contaminants and electron acceptors and large-scale spatial heterogeneities.
ERIC Educational Resources Information Center
Ulukök, Seyma; Sari, Ugur
2016-01-01
In this study, the effects of computer-assisted laboratory applications on pre-service science teachers' attitudes towards science teaching were investigated and the opinions of the pre-service teachers about the application were also determined. The study sample consisted of 46 students studying science teaching Faculty of Education. The study…
NASA Technical Reports Server (NTRS)
Golden, D. C.; Ming, D. W.; Morris, R. V.
2003-01-01
The objective of this study is to conduct simulated Mars-like weathering experiments in the laboratory to determine the weathering products that might form during oxidative, acidic weathering of Mars analog materials.
NASA Astrophysics Data System (ADS)
Fromm, Steven
2017-09-01
In an effort to study and improve the optical trapping efficiency of the 225Ra Electric Dipole Moment experiment, a fully parallelized Monte Carlo simulation of the laser cooling and trapping apparatus was created at Argonne National Laboratory and now maintained and upgraded at Michigan State University. The simulation allows us to study optimizations and upgrades without having to use limited quantities of 225Ra (15 day half-life) in experiment's apparatus. It predicts a trapping efficiency that differs from the observed value in the experiment by approximately a factor of thirty. The effects of varying oven geometry, background gas interactions, laboratory magnetic fields, MOT laser beam configurations and laser frequency noise were studied and ruled out as causes of the discrepancy between measured and predicted values of the overall trapping efficiency. Presently, the simulation is being used to help optimize a planned blue slower laser upgrade in the experiment's apparatus, which will increase the overall trapping efficiency by up to two orders of magnitude. This work is supported by Michigan State University, the Director's Research Scholars Program at the National Superconducting Cyclotron Laboratory, and the U.S. DOE, Office of Science, Office of Nuclear Physics, under Contract DE-AC02-06CH11357.
A Comparative Study Of Dust Devils
NASA Astrophysics Data System (ADS)
Lange, C. F.; Prieto, L. E.
2005-12-01
Spatial variations in the column of water vapour in the Martian near-surface are due to the combined effects of several process within water underground reservoirs and the atmosphere. Among these process, dust devils could be an important local factor in the water concentration levels. In fact, the apparently high occurrence of dust devils could potentially affect the mass transfer rate of water vapour from the Martian regolith. A detailed study of these atmospheric vortices may help to better understand the complex relation between the cycle of water and this Martian atmospheric event. Subsequently, field data are required to provide a close estimation of the dynamics presented in Martian surface. The upcoming Phoenix mission is being designed to investigate these natural events on Mars. However, field studies of dust devils are difficult because of their sporadic, unpredictable occurrence and distance. In contrast, laboratory simulations present a better physical insight into this complex swirling flow by consideration of a much simplified, and more controllable and reproducible model flow. The use of numerical simulations in addition to laboratory experiments can provide complementary information on flow properties in regions where measurements are difficult due to flow profiles. Computational models also allow for significant flexibility in the model layout and they are, therefore, ideally suited for a comparison of different types of model flows. A 3-D numerical study is presented for two different types of dust devil laboratory simulators (Ward, 1952 and Greeley et al., 2001). An initial numerical study was conducted to validate the simulation results with previous laboratory measurements (Lund and Snow, 1993). Secondly, a numerical comparison was carried out between the two tornado-like vortex representations based on kinematic similarities to provide a clear method to relate dust devils in several nature environments, laboratory simulations, and computational models. This was accomplished by examining features of the dust devils in the form of three main flow parameters: the ratio of the inflow layer height h to the updraft radius r_0 (aspect ratio), the radial Reynolds number characterizing the updraft zone, and the ratio of the tangential velocity to the mean radial velocity (swirl ratio) at the radius of the updraft zone, r_0. The detailed analysis of the numerical flow solutions led to a simple definition of h and r_0, valid for the types of model flows analyzed. This study is a necessary part of a larger effort to examine and compare both numerical and laboratory simulations of atmospheric vortices in terrestrial and Martian conditions. References [1] R. Greeley et al., XXXII Lunar and Planetary Science, 2001. [2] D. E. Lund and J. T. Snow, The Tornado: Its Structure, Dynamics, Prediction, and Hazards, 1993, p. 297--306. [3] N. B. Ward, J. Atmos. Sci., 1972, 1194--1204.
Design of a simulation environment for laboratory management by robot organizations
NASA Technical Reports Server (NTRS)
Zeigler, Bernard P.; Cellier, Francois E.; Rozenblit, Jerzy W.
1988-01-01
This paper describes the basic concepts needed for a simulation environment capable of supporting the design of robot organizations for managing chemical, or similar, laboratories on the planned U.S. Space Station. The environment should facilitate a thorough study of the problems to be encountered in assigning the responsibility of managing a non-life-critical, but mission valuable, process to an organized group of robots. In the first phase of the work, we seek to employ the simulation environment to develop robot cognitive systems and strategies for effective multi-robot management of chemical experiments. Later phases will explore human-robot interaction and development of robot autonomy.
Apparatus for precise regulation and chilling of water temperatures in laboratory studies
Burger, C.; ,
1991-01-01
Laboratory simulation of water temperature regimes that occur in subarctic rivers through winter necessitates the ability to maintain near-freezing conditions. A heat-exchangeing apparatus is described that provided a convenient means of simulating the range of temperatures (0.5-12 degrees C) that incubating eggs of salmon (Oncorhynchus spp.) typically experience in south-central Alaska watersheds. The system was reliable, easily maintained precise temperatures at our coldest test levels, and was used over several years with few mechanical complications.
2008-09-30
Nonlinear Internal Tide Generation at the Luzon Strait: Integrating Laboratory Data with Numerics and...laboratory experimental techniques have greatly enhanced the ability to obtained detailed spatiotemporal data for internal waves in challenging regimes...a custom configured wave tank; and to integrate these results with data obtained from numerical simulations, theory and field studies. The principal
DOT National Transportation Integrated Search
2012-04-01
This study involved the identification and evaluation of laboratory conditioning methods and testing protocols considering heat oxidation, moisture, and load that more effectively simulate asphalt mixture aging in the field, and thereby help to prope...
The Berkeley Environmental Simulation Laboratory: Its Use In Environmental Impact Assessment.
ERIC Educational Resources Information Center
Appleyard, Donald; And Others
An environmental simulation laboratory at the University of California, Berkeley, is testing the adequacy of different techniques for simulating environmental experiences. Various levels of realism, with various costs, are available in different presentation modes. The simulations can aid in communication about and the resolution of environmental…
Simulation for analysis and control of superplastic forming. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zacharia, T.; Aramayo, G.A.; Simunovic, S.
1996-08-01
A joint study was conducted by Oak Ridge National Laboratory (ORNL) and the Pacific Northwest Laboratory (PNL) for the U.S. Department of Energy-Lightweight Materials (DOE-LWM) Program. the purpose of the study was to assess and benchmark the current modeling capabilities with respect to accuracy of predictions and simulation time. Two modeling capabilities with respect to accuracy of predictions and simulation time. Two simulation platforms were considered in this study, which included the LS-DYNA3D code installed on ORNL`s high- performance computers and the finite element code MARC used at PNL. both ORNL and PNL performed superplastic forming (SPF) analysis on amore » standard butter-tray geometry, which was defined by PNL, to better understand the capabilities of the respective models. The specific geometry was selected and formed at PNL, and the experimental results, such as forming time and thickness at specific locations, were provided for comparisons with numerical predictions. Furthermore, comparisons between the ORNL simulation results, using elasto-plastic analysis, and PNL`s results, using rigid-plastic flow analysis, were performed.« less
Sarwani, Nabeel; Tappouni, Rafel; Flemming, Donald
2012-08-01
Simulation laboratories use realistic clinical scenarios to train physicians in a controlled environment, especially in potentially life-threatening complications that require prompt management. The objective of our study was to develop a comprehensive program using the simulation laboratory to train radiology residents in the management of acute radiologic emergencies. All radiology residents attended a dedicated simulation laboratory course lasting 3 hours, divided over two sessions. Training included basic patient management skills, management of a tension pneumothorax, massive hemorrhage, and contrast agent reactions. Participants were presented with 20 multiple-choice questions before and after the course. Pre- and posttest results were analyzed, and the McNemar test was used to compare correct responses by individual question. Twenty-six radiology residents attended the class. The average pre- and posttest scores and the average difference between the scores for all residents were 13.8, 17.1, and 3.3, respectively (p < 0.0001). Incorrect answers on the pretest examination that were subsequently answered correctly concerned administration of epinephrine for severe reactions, management of a tension pneumothorax, oxygen therapy, ECG placement, cardiopulmonary resuscitation technique, and where to stand during a code situation. Persistent incorrect answers concerned vasovagal reactions and emergency telephone numbers at an off-site imaging center. Simulation laboratories can be used to teach crisis management and crisis resource management for radiology residents and should be part of the education toolbox. Defined objectives lead to a comprehensive course dealing with the management of acute radiologic emergencies. Such programs can improve the role of radiologists as members of the health care team.
Laboratory experiments in the study of the chemistry of the outer planets.
Scattergood, T W
1987-01-01
The investigation of chemical evolution of bodies in our solar system has, in the past, included observations, theoretical modeling, and laboratory simulations. Of these programs, the last one has been the most criticized due to the inherent difficulties in accurately recreating alien environments in the laboratory. Processes such as wall reactions and changes in chemistry due to difficulties in achieving realistic conditions of temperature, pressure, composition, and energy flux may yield results which are not truly representative of the systems being modeled. However, many laboratory studies have been done which have yielded data useful in planetary science. Gross simulations of atmospheric chemistry have placed constraints on the nature of complex molecules expected in planetary atmospheres. More precise studies of specific chemical processes have provided information about the sources and properties of product gases and aerosols. Determinations of basic properties such as spectral features and reaction rate constants yield data useful in the interpretation of observations and in computational modeling. Alone, and in conjunction with modeling, laboratory experiments will continue to be used to further our understanding of the outer solar system, and some experiments that need to be done are listed.
NASA Astrophysics Data System (ADS)
1981-01-01
Oriel Corporation's simulators have a high pressure xenon lamp whose reflected light is processed by an optical system to produce a uniform solar beam. Because of many different types of applications, the simulators must be adjustable to replicate many different areas of the solar radiation spectrum. Simulators are laboratory tools for such purposes as testing and calibrating solar cells, or other solar energy systems, testing dyes, paints and pigments, pharmaceuticals and cosmetic preparations, plant and animal studies, food and agriculture studies and oceanographic research.
Voice measures of workload in the advanced flight deck: Additional studies
NASA Technical Reports Server (NTRS)
Schneider, Sid J.; Alpert, Murray
1989-01-01
These studies investigated acoustical analysis of the voice as a measure of workload in individual operators. In the first study, voice samples were recorded from a single operator during high, medium, and low workload conditions. Mean amplitude, frequency, syllable duration, and emphasis all tended to increase as workload increased. In the second study, NASA test pilots performed a laboratory task, and used a flight simulator under differing work conditions. For two of the pilots, high workload in the simulator brought about greater amplitude, peak duration, and stress. In both the laboratory and simulator tasks, high workload tended to be associated with more statistically significant drop-offs in the acoustical measures than were lower workload levels. There was a great deal of intra-subject variability in the acoustical measures. The results suggested that in individual operators, increased workload might be revealed by high initial amplitude and frequency, followed by rapid drop-offs over time.
Lectures and Simulation Laboratories to Improve Learners' Conceptual Understanding
ERIC Educational Resources Information Center
Brophy, Sean P.; Magana, Alejandra J.; Strachan, Alejandro
2013-01-01
We studied the use of online molecular dynamics simulations (MD) to enhance student abilities to understand the atomic processes governing plastic deformation in materials. The target population included a second-year undergraduate engineering course in the School of Materials Engineering at Purdue University. The objectives of the study were to…
ERIC Educational Resources Information Center
Balakrishnan, B.; Woods, P. C.
2013-01-01
Over the years, rapid development in computer technology has engendered simulation-based laboratory (lab) in addition to the traditional hands-on (physical) lab. Many higher education institutions adopt simulation lab, replacing some existing physical lab experiments. The creation of new systems for conducting engineering lab activities has raised…
Reproducibility of preclinical animal research improves with heterogeneity of study samples
Vogt, Lucile; Sena, Emily S.; Würbel, Hanno
2018-01-01
Single-laboratory studies conducted under highly standardized conditions are the gold standard in preclinical animal research. Using simulations based on 440 preclinical studies across 13 different interventions in animal models of stroke, myocardial infarction, and breast cancer, we compared the accuracy of effect size estimates between single-laboratory and multi-laboratory study designs. Single-laboratory studies generally failed to predict effect size accurately, and larger sample sizes rendered effect size estimates even less accurate. By contrast, multi-laboratory designs including as few as 2 to 4 laboratories increased coverage probability by up to 42 percentage points without a need for larger sample sizes. These findings demonstrate that within-study standardization is a major cause of poor reproducibility. More representative study samples are required to improve the external validity and reproducibility of preclinical animal research and to prevent wasting animals and resources for inconclusive research. PMID:29470495
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nilsson, Mikael
This 3-year project was a collaboration between University of California Irvine (UC Irvine), Pacific Northwest National Laboratory (PNNL), Idaho National Laboratory (INL), Argonne National Laboratory (ANL) and with an international collaborator at ForschungZentrum Jülich (FZJ). The project was led from UC Irvine under the direction of Profs. Mikael Nilsson and Hung Nguyen. The leads at PNNL, INL, ANL and FZJ were Dr. Liem Dang, Dr. Peter Zalupski, Dr. Nathaniel Hoyt and Dr. Giuseppe Modolo, respectively. Involved in this project at UC Irvine were three full time PhD graduate students, Tro Babikian, Ted Yoo, and Quynh Vo, and one MS student,more » Alba Font Bosch. The overall objective of this project was to study how the kinetics and thermodynamics of metal ion extraction can be described by molecular dynamic (MD) simulations and how the simulations can be validated by experimental data. Furthermore, the project includes the applied separation by testing the extraction systems in a single stage annular centrifugal contactor and coupling the experimental data with computational fluid dynamic (CFD) simulations. Specific objectives of the proposed research were: Study and establish a rigorous connection between MD simulations based on polarizable force fields and extraction thermodynamic and kinetic data. Compare and validate CFD simulations of extraction processes for An/Ln separation using different sizes (and types) of annular centrifugal contactors. Provide a theoretical/simulation and experimental base for scale-up of batch-wise extraction to continuous contactors. We approached objective 1 and 2 in parallel. For objective 1 we started by studying a well established extraction system with a relatively simple extraction mechanism, namely tributyl phosphate. What we found was that well optimized simulations can inform experiments and new information on TBP behavior was presented in this project, as well be discussed below. The second objective proved a larger challenge and most of the efforts were devoted to experimental studies.« less
A laboratory rainfall simulator to study the soil erosion and runoff water
NASA Astrophysics Data System (ADS)
Cancelo González, Javier; Rial, M. E.; Díaz-Fierros, Francisco
2010-05-01
The soil erosion and the runoff water composition in some areas affected by forest fires or submitted to intensive agriculture are an important factor to keep an account, particularly in sensitive areas like estuary and rias that have a high importance in the socioeconomic development of some regions. An understanding of runoff production indicates the processes by which pollutants reach streams and also indicates the management techniques that might be uses to minimize the discharge of these materials into surface waters. One of the most methodology implemented in the soil erosion studies is a rainfall simulation. This method can reproduce the natural soil degradation processes in field or laboratory experiences. With the aim of improve the rainfall-runoff generation, a laboratory rainfall simulator which incorporates a fan-like intermittent water jet system for rainfall generation were modified. The major change made to the rainfall simulator consist in a system to coupling stainless steel boxes, whose dimensions are 12 x 20 x 45 centimeters, and it allows to place soil samples under the rainfall simulator. Previously these boxes were used to take soil samples in field with more of 20 centimeters of depth, causing the minimum disturbance in their properties and structure. These new implementations in the rainfall simulator also allow collect water samples of runoff in two ways: firstly, the rain water that constituted the overland flow or direct runoff and besides the rain water seeps into the soil by the process of infiltration and contributed to the subsurface runoff. Among main the variables controlled in the rainfall simulations were the soil slope and the intensity and duration of rainfall. With the aim of test the prototype, six soil samples were collected in the same sampling point and subjected to rainfall simulations in laboratory with the same intensity and duration. Two samples will constitute the control test, and they were fully undisturbed, and four samples were subjected to controlled burnings with different fire severity: two samples burnt to 250°C and the other two samples burnt to 450°C. Preliminary laboratory data of soil erosion and surface and subsurface runoff were obtained. The water parameters analysed were: pH, electrical conductivity, temperature (in the moment of sampling) and suspended sediments, ammonium, nitrates, total nitrogen (Kjeldahl method), within 24 hours after sampling.
NASA Technical Reports Server (NTRS)
Steffes, Paul G.
1987-01-01
Radio absorptivity data for planetary atmospheres obtained from spacecraft radio occultation experiments and Earth-based radio astronomical observations can be used to infer abundances of microwave absorbing atmospheric constituents in those atmospheres, as long as reliable information regarding the microwave absorping properties of potential constituents is available. The use of theoretically derived microwave absorption properties for such atmospheric constituents, or laboratory measurements of such properties under environmental conditions which are significantly different than those of the planetary atmosphere being studied, often leads to significant misinterpretation of available opacity data. Laboratory measurement of the microwave properties of atmospheric gases under simulated conditions for the outer planets were conducted. Results of these measurements are discussed.
FORCED AIR VENTILATION FOR REMEDIATION OF UNSATURATED SOILS CONTAMINATED BY VOC
Parameters which were expected to control the removal process of VOCs from contaminated soil during the SVE operation were studied by means of numerical simulations and laboratory experiments in this project. Experimental results of SVE with soil columns in the laboratory indicat...
ERIC Educational Resources Information Center
Woodfield, Brian F.; Andrus, Merritt B.; Waddoups, Gregory L.; Moore, Melissa S.; Swan, Richard; Allen, Rob; Bodily, Greg; Andersen, Tricia; Miller, Jordan; Simmons, Bryon; Stanger, Richard
2005-01-01
A set of sophisticated and realistic laboratory simulations is created for use in freshman- and sophomore-level chemistry classes and laboratories called 'Virtual ChemLab'. A detailed assessment of student responses is provided and the simulation's pedagogical utility is described using the organic simulation.
Recent Progress in Laboratory Astrophysics and Astrochemistry Achieved with the COSmIC Facility
NASA Technical Reports Server (NTRS)
Salama, Farid; Sciamma-O'Brien, Ella; Bejaoui, Salma
2017-01-01
We describe the characteristics and the capabilities of the laboratory facility, COSmIC, that was developed at NASA Ames to generate, process and analyze interstellar, circumstellar and planetary analogs in the laboratory. COSmIC stands for "Cosmic Simulation Chamber" and is dedicated to the study of neutral and ionized molecules and nanoparticles under the low temperature and high vacuum conditions that are required to simulate various space environments such as diffuse interstellar clouds, circumstellar outflows and planetary atmospheres. COSmIC integrates a variety of state-of-the-art instruments that allow recreating simulated space conditions to generate, process and monitor cosmic analogs in the laboratory. The COSmIC experimental setup is composed of a Pulsed Discharge Nozzle (PDN) expansion, that generates a plasma in the stream of a free supersonic jet expansion, coupled to high-sensitivity, complementary in situ diagnostics: cavity ring down spectroscopy (CRDS) and laser induced fluorescence (LIF) systems for photonic detection, and Reflectron Time-Of-Flight Mass Spectrometer (ReTOF-MS) for mass detection. Recent results obtained using COSmIC will be highlighted. In particular, the progress that has been achieved in the domain of the diffuse interstellar bands (DIBs) and in monitoring, in the laboratory, the formation of circumstellar dust grains and planetary atmosphere aerosols from their gas-phase molecular precursors. Plans for future laboratory experiments on interstellar and planetary molecules and grains will also be addressed, as well as the implications of the studies underway for astronomical observations and past and future space mission data analysis.
Feasibility Assessment of CO2 Sequestration and Enhanced Recovery in Gas Shale Reservoirs
NASA Astrophysics Data System (ADS)
Vermylen, J. P.; Hagin, P. N.; Zoback, M. D.
2008-12-01
CO2 sequestration and enhanced methane recovery may be feasible in unconventional, organic-rich, gas shale reservoirs in which the methane is stored as an adsorbed phase. Previous studies have shown that organic-rich, Appalachian Devonian shales adsorb approximately five times more carbon dioxide than methane at reservoir conditions. However, the enhanced recovery and sequestration concept has not yet been tested for gas shale reservoirs under realistic flow and production conditions. Using the lessons learned from previous studies on enhanced coalbed methane (ECBM) as a starting point, we are conducting laboratory experiments, reservoir modeling, and fluid flow simulations to test the feasibility of sequestration and enhanced recovery in gas shales. Our laboratory work investigates both adsorption and mechanical properties of shale samples to use as inputs for fluid flow simulation. Static and dynamic mechanical properties of shale samples are measured using a triaxial press under realistic reservoir conditions with varying gas saturations and compositions. Adsorption is simultaneously measured using standard, static, volumetric techniques. Permeability is measured using pulse decay methods calibrated to standard Darcy flow measurements. Fluid flow simulations are conducted using the reservoir simulator GEM that has successfully modeled enhanced recovery in coal. The results of the flow simulation are combined with the laboratory results to determine if enhanced recovery and CO2 sequestration is feasible in gas shale reservoirs.
NASA Astrophysics Data System (ADS)
Riaz, Muhammad
The purpose of this study was to examine how simulations in physics class, class management, laboratory practice, student engagement, critical thinking, cooperative learning, and use of simulations predicted the percentage of students achieving a grade point average of B or higher and their academic performance as reported by teachers in secondary school physics classes. The target population consisted of secondary school physics teachers who were members of Science Technology, Engineeering and,Mathematics Teachers of New York City (STEMteachersNYC) and American Modeling Teachers Association (AMTA). They used simulations in their physics classes in the 2013 and 2014 school years. Subjects for this study were volunteers. A survey was constructed based on a literature review. Eighty-two physics teachers completed the survey about instructional practice in physics. All respondents were anonymous. Classroom management was the only predictor of the percent of students achieving a grade point average of B or higher in high school physics class. Cooperative learning, use of simulations, and student engagement were predictors of teacher's views of student academic performance in high school physics class. All other variables -- class management, laboratory practice, critical thinking, and teacher self-efficacy -- were not predictors of teacher's views of student academic performance in high school physics class. The implications of these findings were discussed and recommendations for physics teachers to improve student learning were presented.
GCR Simulator Reference Field and a Spectral Approach for Laboratory Simulation
NASA Technical Reports Server (NTRS)
Slaba, Tony C.; Blattnig, Steve R.; Norbury, John W.; Rusek, Adam; La Tessa, Chiara; Walker, Steven A.
2015-01-01
The galactic cosmic ray (GCR) simulator at the NASA Space Radiation Laboratory (NSRL) is intended to deliver the broad spectrum of particles and energies encountered in deep space to biological targets in a controlled laboratory setting. In this work, certain aspects of simulating the GCR environment in the laboratory are discussed. Reference field specification and beam selection strategies at NSRL are the main focus, but the analysis presented herein may be modified for other facilities. First, comparisons are made between direct simulation of the external, free space GCR field and simulation of the induced tissue field behind shielding. It is found that upper energy constraints at NSRL limit the ability to simulate the external, free space field directly (i.e. shielding placed in the beam line in front of a biological target and exposed to a free space spectrum). Second, variation in the induced tissue field associated with shielding configuration and solar activity is addressed. It is found that the observed variation is likely within the uncertainty associated with representing any GCR reference field with discrete ion beams in the laboratory, given current facility constraints. A single reference field for deep space missions is subsequently identified. Third, an approach for selecting beams at NSRL to simulate the designated reference field is presented. Drawbacks of the proposed methodology are discussed and weighed against alternative simulation strategies. The neutron component and track structure characteristics of the simulated field are discussed in this context.
Robustness and Uncertainty: Applications for Policy in Climate and Hydrological Modeling
NASA Astrophysics Data System (ADS)
Fields, A. L., III
2015-12-01
Policymakers must often decide how to proceed when presented with conflicting simulation data from hydrological, climatological, and geological models. While laboratory sciences often appeal to the reproducibility of results to argue for the validity of their conclusions, simulations cannot use this strategy for a number of pragmatic and methodological reasons. However, robustness of predictions and causal structures can serve the same function for simulations as reproducibility does for laboratory experiments and field observations in either adjudicating between conflicting results or showing that there is insufficient justification to externally validate the results. Additionally, an interpretation of the argument from robustness is presented that involves appealing to the convergence of many well-built and diverse models rather than the more common version which involves appealing to the probability that one of a set of models is likely to be true. This interpretation strengthens the case for taking robustness as an additional requirement for the validation of simulation results and ultimately supports the idea that computer simulations can provide information about the world that is just as trustworthy as data from more traditional laboratory studies and field observations. Understanding the importance of robust results for the validation of simulation data is especially important for policymakers making decisions on the basis of potentially conflicting models. Applications will span climate, hydrological, and hydroclimatological models.
Electrostatic atomization--Experiment, theory and industrial applications
NASA Astrophysics Data System (ADS)
Okuda, H.; Kelly, Arnold J.
1996-05-01
Experimental and theoretical research has been initiated at the Princeton Plasma Physics Laboratory on the electrostatic atomization process in collaboration with Charged Injection Corporation. The goal of this collaboration is to set up a comprehensive research and development program on the electrostatic atomization at the Princeton Plasma Physics Laboratory so that both institutions can benefit from the collaboration. Experimental, theoretical and numerical simulation approaches are used for this purpose. An experiment consisting of a capillary sprayer combined with a quadrupole mass filter and a charge detector was installed at the Electrostatic Atomization Laboratory to study fundamental properties of the charged droplets such as the distribution of charges with respect to the droplet radius. In addition, a numerical simulation model is used to study interaction of beam electrons with atmospheric pressure water vapor, supporting an effort to develop an electrostatic water mist fire-fighting nozzle.
NETL Extreme Drilling Laboratory Studies High Pressure High Temperature Drilling Phenomena
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lyons, K.D.; Honeygan, S.; Moroz, T
2007-06-01
The U.S. Department of Energy’s National Energy Technology Laboratory (NETL) established an Extreme Drilling Lab to engineer effective and efficient drilling technologies viable at depths greater than 20,000 feet. This paper details the challenges of ultra-deep drilling, documents reports of decreased drilling rates as a result of increasing fluid pressure and temperature, and describes NETL’s Research and Development activities. NETL is invested in laboratory-scale physical simulation. Their physical simulator will have capability of circulating drilling fluids at 30,000 psi and 480 °F around a single drill cutter. This simulator will not yet be operational by the planned conference dates; therefore,more » the results will be limited to identification of leading hypotheses of drilling phenomena and NETL’s test plans to validate or refute such theories. Of particular interest to the Extreme Drilling Lab’s studies are the combinatorial effects of drilling fluid pressure, drilling fluid properties, rock properties, pore pressure, and drilling parameters, such as cutter rotational speed, weight on bit, and hydraulics associated with drilling fluid introduction to the rock-cutter interface. A detailed discussion of how each variable is controlled in a laboratory setting will be part of the conference paper and presentation.« less
NASA Astrophysics Data System (ADS)
Davidson, Ronald C.; Efthimion, Philip C.; Gilson, Erik; Majeski, Richard; Qin, Hong
2002-01-01
The Paul Trap Simulator Experiment (PTSX) is under construction at the Princeton Plasma Physics Laboratory to simulate intense beam propagation through a periodic quadrupole magnetic field. In the Paul trap configuration, a long nonneutral plasma column is confined axially by dc voltages on end cylinders at z=+L and z=-L, and transverse confinement is provided by segmented cylindrical electrodes with applied oscillatory voltages ±V0(t) over 90° segments. Because the transverse focusing force is similar in waveform to that produced by a discrete set of periodic quadrupole magnets in a frame moving with the beam, the Paul trap configuration offers the possibility of simulating intense beam propagation in a compact laboratory facility. The experimental layout is described, together with the planned experiments to study beam mismatch, envelope instabilities, halo particle production, and collective wave excitations.
NASA Astrophysics Data System (ADS)
Jost, Bernhard; Pommerol, Antoine; Poch, Olivier; Carrasco, Nathalie; Szopa, Cyril; Thomas, Nicolas
2015-11-01
The OSIRIS imaging system [1] onboard European Space Agency’s Rosetta mission has been orbiting the comet 67P/Churyumov-Gerasimenko (67P) since August 2014. It provides an enormous quantity of high resolution images of the nucleus in the visible spectral range. 67P revealed an unexpected diversity of complex surface structures and spectral properties have also been measured [2].To better interpret this data, a profound knowledge of laboratory analogs of cometary surfaces is essential. For this reason we have set up the LOSSy laboratory (Laboratory for Outflow Studies of Sublimating Materials) to study the spectrophotometric properties of ice-bearing cometary nucleus analogs. The main focus lies on the characterization of the surface evolution under simulated space conditions. The laboratory is equipped with two facilities: the PHIRE-2 radio-goniometer [3], designed to measure the bidirectional visible reflectance of samples under a wide range of geometries and the SCITEAS simulation chamber [4], designed to study the evolution of icy samples subliming under low pressure/temperature conditions by hyperspectral imaging in the VIS-NIR range. Different microscopes complement the two facilities.We present laboratory data of different types of fine grained ice particles mixed with non-volatile components (complex organic matter and minerals). As the ice sublimes, a deposition lag of non-volatile constituents is built-up on top of the ice, possibly mimic a cometary surface. The bidirectional reflectance of the samples have been characterized before and after the sublimation process.A comparison of our laboratory findings with recent OSIRIS data [5] will be presented.[1] Keller, H. U., et al., 2007, Space Sci. Rev., 128, 26[2] Thomas, N. , 2015, Science, 347, Issue 6220, aaa0440[3] Jost, B., submitted, Icarus[4] Pommerol, A., et al., 2015. Planet Space Sci 109:106-122.[5] Fornasier, S., et al., in press. Icarus, arXiv:1505.06888
Study of Physiological Responses to Acute Carbon Monoxide Exposure with a Human Patient Simulator
ERIC Educational Resources Information Center
Cesari, Whitney A.; Caruso, Dominique M.; Zyka, Enela L.; Schroff, Stuart T.; Evans, Charles H., Jr.; Hyatt, Jon-Philippe K.
2006-01-01
Human patient simulators are widely used to train health professionals and students in a clinical setting, but they also can be used to enhance physiology education in a laboratory setting. Our course incorporates the human patient simulator for experiential learning in which undergraduate university juniors and seniors are instructed to design,…
Schimmel, Daniel R; Sweis, Ranya; Cohen, Elaine R; Davidson, Charles; Wayne, Diane B
2016-02-15
The purpose of this study is to determine the effects of simulation-based medical education (SBME) on the skills required to perform coronary angiography in the cardiac catheterization laboratory. Cardiovascular fellows commonly learn invasive procedures on patients. Because this approach is not standardized, it can result in inconsistent skill acquisition through exclusion of concepts and skills. Also, the learning curve varies between trainees yielding variability in skill acquisition. Therefore, coronary angiography skills are an excellent target for SBME in an environment in which direct patient care is not jeopardized. From January 2013 to June 2013, 14 cardiovascular fellows entering the cardiac catheterization laboratory at a tertiary care teaching hospital were tested on an endovascular simulator to assess baseline skills. All fellows subsequently underwent didactic teaching and preceptor-lead training on the endovascular simulator. Topics included basic catheterization skills and a review of catheterization laboratory systems. Following training, all fellows underwent a post-training assessment on the endovascular simulator. Paired t tests were used to compare items on the skills checklist and simulator defined variables. Cardiovascular fellows scored significantly higher on a diagnostic coronary angiography skills checklist following SBME using an endovascular simulator. The mean pretest score was 66.6% (SD = 9.7%) compared to 86.0% (SD = 6.3%) following simulator training (P < 0.001). Additional findings include significant reduction in procedure time and use of cine-fluoroscopy at posttest. SBME significantly improved cardiovascular fellows' performance of simulated coronary angiography skills. Standardized simulation-based education is a valuable adjunct to traditional clinical education for cardiovascular fellows. © 2015 Wiley Periodicals, Inc.
Modeling of Army Research Laboratory EMP simulators
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miletta, J.R.; Chase, R.J.; Luu, B.B.
1993-12-01
Models are required that permit the estimation of emitted field signatures from EMP simulators to design the simulator antenna structure, to establish the usable test volumes, and to estimate human exposure risk. This paper presents the capabilities and limitations of a variety of EMP simulator models useful to the Army's EMP survivability programs. Comparisons among frequency and time-domain models are provided for two powerful US Army Research Laboratory EMP simulators: AESOP (Army EMP Simulator Operations) and VEMPS II (Vertical EMP Simulator II).
NASA Technical Reports Server (NTRS)
Yuen, G. U.; Cronin, J. R.; Blair, N. E.; Desmarais, D. J.; Chang, S.
1991-01-01
Recently, in our laboratories, samples of Murchison acetic acid were decarboxylated successfully and the carbon isotopic composition was measured for the methane released by this procedure. These analyses showed significant differences in C-13/C-12 ratios for the methyl and carboxyl carbons of the acetic acid molecule, strongly suggesting that more than one carbon source may be involved in the synthesis of the Murchison organic compounds. On the basis of this finding, laboratory model systems simulating cosmochemical synthesis are being studied, especially those processes capable of involving two or more starting carbon sources.
Enhanced verification test suite for physics simulation codes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kamm, James R.; Brock, Jerry S.; Brandon, Scott T.
2008-09-01
This document discusses problems with which to augment, in quantity and in quality, the existing tri-laboratory suite of verification problems used by Los Alamos National Laboratory (LANL), Lawrence Livermore National Laboratory (LLNL), and Sandia National Laboratories (SNL). The purpose of verification analysis is demonstrate whether the numerical results of the discretization algorithms in physics and engineering simulation codes provide correct solutions of the corresponding continuum equations.
Modeling Supernova Shocks with Intense Lasers.
NASA Astrophysics Data System (ADS)
Blue, Brent
2006-04-01
Large-scale directional outflows of supersonic plasma are ubiquitous phenomena in astrophysics, with specific application to supernovae. The traditional approach to understanding such phenomena is through theoretical analysis and numerical simulations. However, theoretical analysis might not capture all the relevant physics and numerical simulations have limited resolution and fail to scale correctly in Reynolds number and perhaps other key dimensionless parameters. Recent advances in high energy density physics using large inertial confinement fusion devices now allow controlled laboratory experiments on macroscopic volumes of plasma of direct relevance to astrophysics. This talk will present an overview of these facilities as well as results from current laboratory astrophysics experiments designed to study hydrodynamic jets and Rayleigh-Taylor mixing. This work is performed under the auspices of the U. S. DOE by Lawrence Livermore National Laboratory under Contract No. W-7405-ENG-48, Los Alamos National Laboratory under Contract No. W-7405-ENG-36, and the Laboratory for Laser Energetics under Contract No. DE-FC03-92SF19460.
Simulating Laboratory Procedures.
ERIC Educational Resources Information Center
Baker, J. E.; And Others
1986-01-01
Describes the use of computer assisted instruction in a medical microbiology course. Presents examples of how computer assisted instruction can present case histories in which the laboratory procedures are simulated. Discusses an authoring system used to prepare computer simulations and provides one example of a case history dealing with fractured…
ERIC Educational Resources Information Center
Simon, Nicole A.
2013-01-01
Virtual laboratory experiments using interactive computer simulations are not being employed as viable alternatives to laboratory science curriculum at extensive enough rates within higher education. Rote traditional lab experiments are currently the norm and are not addressing inquiry, Critical Thinking, and cognition throughout the laboratory…
Investigations in Computer-Aided Instruction and Computer-Aided Controls. Final Report.
ERIC Educational Resources Information Center
Rosenberg, R.C.; And Others
These research projects, designed to delve into certain relationships between humans and computers, are focused on computer-assisted instruction and on man-computer interaction. One study demonstrates that within the limits of formal engineering theory, a computer simulated laboratory (Dynamic Systems Laboratory) can be built in which freshmen…
GATE AND VACUUM FLUSHING OF SEWER SEDIMENT: LABORATORY TESTING
The objective of this study was to test the performance of a traditional gate-flushing device and a newly-designed vacuum-flushing device in removing sediment from combined sewers and CSO storage tanks. A laboratory hydraulic flume was used to simulate a reach of sewer or storag...
DOT National Transportation Integrated Search
1988-08-01
This paper deals with the use of response/recovery rate to auditory startle as a laboratory technique for simulating some of the principal aspects of the initial shock phase of sudden emergency situations. It is submitted that auditory startle, with ...
Preliminary aerosol generator design studies
NASA Technical Reports Server (NTRS)
Stampfer, J. F., Jr.
1976-01-01
The design and construction of a prototype vaporization generator for highly dispersed sodium chloride aerosols is described. The aerosol generating system is to be used in the Science Simulator of the Cloud Physics Laboratory Project and as part of the Cloud Physics Laboratory payload to be flown on the shuttle/spacelab.
Laboratory simulations of the atmospheric mixed-layer in flow over complex topography
A laboratory study of the influence of complex terrain on the interface between a well-mixed boundary layer and an elevated stratified layer was conducted in the towing-tank facility of the U.S. Environmental Protection Agency. The height of the mixed layer in the daytime boundar...
Acha, Robert; Brey, Richard; Capello, Kevin
2013-02-01
A torso phantom was developed by the Lawrence Livermore National Laboratory (LLNL) that serves as a standard for intercomparison and intercalibration of detector systems used to measure low-energy photons from radionuclides, such as americium deposited in the lungs. DICOM images of the second-generation Human Monitoring Laboratory-Lawrence Livermore National Laboratory (HML-LLNL) torso phantom were segmented and converted into three-dimensional (3D) voxel phantoms to simulate the response of high purity germanium (HPGe) detector systems, as found in the HML new lung counter using a Monte Carlo technique. The photon energies of interest in this study were 17.5, 26.4, 45.4, 59.5, 122, 244, and 344 keV. The detection efficiencies at these photon energies were predicted for different chest wall thicknesses (1.49 to 6.35 cm) and compared to measured values obtained with lungs containing (241)Am (34.8 kBq) and (152)Eu (10.4 kBq). It was observed that no statistically significant differences exist at the 95% confidence level between the mean values of simulated and measured detection efficiencies. Comparisons between the simulated and measured detection efficiencies reveal a variation of 20% at 17.5 keV and 1% at 59.5 keV. It was found that small changes in the formulation of the tissue substitute material caused no significant change in the outcome of Monte Carlo simulations.
ERIC Educational Resources Information Center
Hati, Sanchita; Bhattacharyya, Sudeep
2016-01-01
A project-based biophysical chemistry laboratory course, which is offered to the biochemistry and molecular biology majors in their senior year, is described. In this course, the classroom study of the structure-function of biomolecules is integrated with the discovery-guided laboratory study of these molecules using computer modeling and…
Akchata, Suman; Lavanya, K; Shivanand, Bhushan
2017-01-01
Decontamination of various working surfaces with sodium pertechnetate minor spillage is essential for maintaining good radiation safety practices as well as for regulatory compliance. To observe the influences of decontaminating agents and swipe materials on different type of surfaces used in nuclear medicine laboratory work area wet spilled with 99m-technetium (99mTc) sodium pertechnetate. Lab-simulated working surface materials. Experimental study design. Direct decontamination method on dust-free lab simulated new working surfaces [stainless steel, polyvinyl chloride (PVC), Perspex, resin] using four decontaminating agents [tap water, soap water (SW), Radiacwash, and spirit] with four different swipe material [cotton, tissue paper (TP), Whatman paper (WP), adsorbent sheet (AS)] was taken 10 samples (n = 10) for each group. Parametric test two-way analysis of variance is used with significance level of 0.005, was used to evaluate statistical differences between different group of decontaminating agent and swipe material, and the results are expressed in mean ± SD. Decontamination factor is calculated after five cleaning for each group. A total of 160 samples result calculated using four decontaminating agent (tap water, SW, Radiacwash, and spirit), four swipe material (cotton, TP, WP, and AS) for commonly used surface (stainless steel, PVC, Perspex, resin) using direct method by 10 samples (n = 10) for each group. Tap water is the best decontaminating agent compared with SW, Radiac wash and spirit for the laboratory simulated stainless steel, PVC, and Perspex surface material, whereas in case of resin surface material, SW decontaminating agent is showing better effectiveness. Cotton is the best swipe material compared to WP-1, AS and TP for the stainless steel, PVC, Perspex, and resin laboratory simulated surface materials. Perspex and stainless steel are the most suitable and recommended laboratory surface material compared to PVC and resin in nuclear medicine. Radiacwash may show better result for 99mTc labelled product and other radionuclide contamination on the laboratory working surface area.
The utility of the AusEd driving simulator in the clinical assessment of driver fatigue.
Desai, Anup V; Wilsmore, Brad; Bartlett, Delwyn J; Unger, Gunnar; Constable, Ben; Joffe, David; Grunstein, Ronald R
2007-08-01
Several driving simulators have been developed which range in complexity from PC based driving tasks to advanced "real world" simulators. The AusEd driving simulator is a PC based task, which was designed to be conducive to and test for driver fatigue. This paper describes the AusEd driving simulator in detail, including the technical requirements, hardware, screen and file outputs, and analysis software. Some aspects of the test are standardized, while others can be modified to suit the experimental situation. The AusEd driving simulator is sensitive to performance decrement from driver fatigue in the laboratory setting, potentially making it useful as a laboratory or office based test for driver fatigue risk management. However, more research is still needed to correlate laboratory based simulator performance with real world driving performance and outcomes.
Computer Simulation of Laboratory Experiments: An Unrealized Potential.
ERIC Educational Resources Information Center
Magin, D. J.; Reizes, J. A.
1990-01-01
Discussion of the use of computer simulation for laboratory experiments in undergraduate engineering education focuses on work at the University of New South Wales in the instructional design and software development of a package simulating a heat exchange device. The importance of integrating theory, design, and experimentation is also discussed.…
NASA Astrophysics Data System (ADS)
Fonseca, Ana S.; Kuijpers, Eelco; Kling, Kirsten I.; Levin, Marcus; Koivisto, Antti J.; Nielsen, Signe H.; Fransman, W.; Fedutik, Yijri; Jensen, Keld A.; Koponen, Ismo K.
2018-02-01
Fume hoods are one of the most common types of equipment applied to reduce the potential of particle exposure in laboratory environments. A number of previous studies have shown particle release during work with nanomaterials under fume hoods. Here, we assessed laboratory workers' inhalation exposure during synthesis and handling of CuO, TiO2 and ZnO in a fume hood. In addition, we tested the capacity of a fume hood to prevent particle release to laboratory air during simulated spillage of different powders (silica fume, zirconia TZ-3Y and TiO2). Airborne particle concentrations were measured in near field, far field, and in the breathing zone of the worker. Handling CuO nanoparticles increased the concentration of small particles (< 58 nm) inside the fume hood (up to 1 × 105 cm-3). Synthesis, handling and packaging of ZnO and TiO2 nanoparticles did not result in detectable particle release to the laboratory air. Simulated powder spills showed a systematic increase in the particle concentrations inside the fume hood with increasing amount of material and drop height. Despite powder spills were sometimes observed to eject into the laboratory room, the spill events were rarely associated with notable release of particles from the fume hood. Overall, this study shows that a fume hood generally offers sufficient exposure control during synthesis and handling of nanomaterials. An appropriate fume hood with adequate sash height and face velocity prevents 98.3% of particles release into the surrounding environment. Care should still be made to consider spills and high cleanliness to prevent exposure via resuspension and inadvertent exposure by secondary routes.
ERIC Educational Resources Information Center
Winberg, T. Mikael; Berg, C. Anders R.
2007-01-01
To enhance the learning outcomes achieved by students, learners undertook a computer-simulated activity based on an acid-base titration prior to a university-level chemistry laboratory activity. Students were categorized with respect to their attitudes toward learning. During the laboratory exercise, questions that students asked their assistant…
Laboratory simulation of the action of weightlessness on the human organism
NASA Technical Reports Server (NTRS)
Genin, A. M.
1977-01-01
A brief history of attemps by the U.S. and the U.S.S.R. to simulate weightlessness in the laboratory is presented. Model for laboratory modeling of weightlessness included the bed regimen, the clinostat, and water immersion. An outline of immediate physiological effects of weightlessness and long term effects is offered.
NLS Flight Simulation Laboratory (FSL) documentation
NASA Technical Reports Server (NTRS)
1995-01-01
The Flight Simulation Laboratory (FSL) Electronic Documentation System design consists of modification and utilization of the MSFC Integrated Engineering System (IES), translation of the existing FSL documentation to an electronic format, and generation of new drawings to represent the Engine Flight Simulation Laboratory design and implementation. The intent of the electronic documentation is to provide ease of access, local print/plot capabilities, as well as the ability to correct and/or modify the stored data by network users who are authorized to access this information.
Galactic Cosmic Ray Simulator at the NASA Space Radiation Laboratory
NASA Technical Reports Server (NTRS)
Norbury, John W.; Slaba, Tony C.; Rusek, Adam
2015-01-01
The external Galactic Cosmic Ray (GCR) spectrum is significantly modified when it passes through spacecraft shielding and astronauts. One approach for simulating the GCR space radiation environment is to attempt to reproduce the unmodified, external GCR spectrum at a ground based accelerator. A possibly better approach would use the modified, shielded tissue spectrum, to select accelerator beams impinging on biological targets. NASA plans for implementation of a GCR simulator at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory will be discussed.
NASA Constellation Distributed Simulation Middleware Trade Study
NASA Technical Reports Server (NTRS)
Hasan, David; Bowman, James D.; Fisher, Nancy; Cutts, Dannie; Cures, Edwin Z.
2008-01-01
This paper presents the results of a trade study designed to assess three distributed simulation middleware technologies for support of the NASA Constellation Distributed Space Exploration Simulation (DSES) project and Test and Verification Distributed System Integration Laboratory (DSIL). The technologies are the High Level Architecture (HLA), the Test and Training Enabling Architecture (TENA), and an XML-based variant of Distributed Interactive Simulation (DIS-XML) coupled with the Extensible Messaging and Presence Protocol (XMPP). According to the criteria and weights determined in this study, HLA scores better than the other two for DSES as well as the DSIL.
Identifying the potential of changes to blood sample logistics using simulation.
Jørgensen, Pelle; Jacobsen, Peter; Poulsen, Jørgen Hjelm
2013-01-01
Using simulation as an approach to display and improve internal logistics at hospitals has great potential. This study shows how a simulation model displaying the morning blood-taking round at a Danish public hospital can be developed and utilized with the aim of improving the logistics. The focus of the simulation was to evaluate changes made to the transportation of blood samples between wards and the laboratory. The average- (AWT) and maximum waiting time (MWT) from a blood sample was drawn at the ward until it was received at the laboratory, and the distribution of arrivals of blood samples in the laboratory were used as the evaluation criteria. Four different scenarios were tested and compared with the current approach: (1) Using AGVs (mobile robots), (2) using a pneumatic tube system, (3) using porters that are called upon, or (4) using porters that come to the wards every 45 minutes. Furthermore, each of the scenarios was tested in terms of what amount of resources would give the optimal result. The simulations showed a big improvement potential in implementing a new technology/mean for transporting the blood samples. The pneumatic tube system showed the biggest potential lowering the AWT and MWT with approx. 36% and 18%, respectively. Additionally, all of the scenarios had a more even distribution of arrivals except for porters coming to the wards every 45 min. As a consequence of the results obtained in the study, the hospital decided to implement a pneumatic tube system.
Feasibility Study of Laboratory Simulation of Single-Stage-to-Orbit Vehicle Base Heating
NASA Technical Reports Server (NTRS)
Park, Chung Sik; Sharma, Surendra; Edwards, Thomas A. (Technical Monitor)
1995-01-01
The feasibility of simulating in a laboratory the heating environment of the base region of the proposed reusable single-stage-to-orbit vehicle during its ascent is examined. The propellant is assumed to consist of hydrocarbon (RP1), liquid hydrogen (LH2), and liquid oxygen (LO2), which produces CO and H2 as the main combustible components of the exhaust effluent. Since afterburning in the recirculating region can dictate the temperature of the base flowfield and ensuing heating phenomena, laboratory simulation focuses on the thermochemistry of the afterburning. By extrapolating the Saturn V flight data, the Damkohler number, in the base region with afterburning for SSTO vehicle, is estimated to be between 30 and 140. It is shown that a flow with a Damkohler number of 1.8 to 25 can be produced in an impulse ground test facility. Even with such a reduced Damkohler number, the experiment can adequately reproduce the main features of the flight environment.
UV–Vis Light-induced Aging of Titan’s Haze and Ice
NASA Astrophysics Data System (ADS)
Couturier-Tamburelli, Isabelle; Piétri, Nathalie; Le Letty, Vincent; Chiavassa, Thierry; Gudipati, Murthy
2018-01-01
The study of the photochemical aging of aerosols is an important tool for understanding Titan’s stratosphere/troposphere composition and evolution, particularly the haze. Laboratory simulations of the photoreactivity of the haze aerosol analogs provide insight into the photochemical evolution of Titan’s atmosphere at and below the haze layers. Here we use experimental simulations to investigate the evolution of the laboratory analogs of these organic aerosols under ultraviolet (UV)–visible (Vis) photons, which make it through the haze layers during their sedimentation process. We present experimental results for the aging of Titan’s aerosol analogs obtained from two dominant nitrogen-containing organics, HC3N and HCN, under simulated Titan atmospheric conditions (photons and temperature). We report that volatile nitriles condensed on haze particles could be incorporated through photochemistry and provide one such sink mechanism for nitrile compounds. We provide laboratory evidence that the organic aerosols could photochemically evolve during their sedimentation through Titan’s atmosphere.
Preliminary SAGE Simulations of Volcanic Jets Into a Stratified Atmosphere
NASA Astrophysics Data System (ADS)
Peterson, A. H.; Wohletz, K. H.; Ogden, D. E.; Gisler, G. R.; Glatzmaier, G. A.
2007-12-01
The SAGE (SAIC Adaptive Grid Eulerian) code employs adaptive mesh refinement in solving Eulerian equations of complex fluid flow desirable for simulation of volcanic eruptions. The goal of modeling volcanic eruptions is to better develop a code's predictive capabilities in order to understand the dynamics that govern the overall behavior of real eruption columns. To achieve this goal, we focus on the dynamics of underexpended jets, one of the fundamental physical processes important to explosive eruptions. Previous simulations of laboratory jets modeled in cylindrical coordinates were benchmarked with simulations in CFDLib (Los Alamos National Laboratory), which solves the full Navier-Stokes equations (includes viscous stress tensor), and showed close agreement, indicating that adaptive mesh refinement used in SAGE may offset the need for explicit calculation of viscous dissipation.We compare gas density contours of these previous simulations with the same initial conditions in cylindrical and Cartesian geometries to laboratory experiments to determine both the validity of the model and the robustness of the code. The SAGE results in both geometries are within several percent of the experiments for position and density of the incident (intercepting) and reflected shocks, slip lines, shear layers, and Mach disk. To expand our study into a volcanic regime, we simulate large-scale jets in a stratified atmosphere to establish the code's ability to model a sustained jet into a stable atmosphere.
Direct simulations of chemically reacting turbulent mixing layers, part 2
NASA Technical Reports Server (NTRS)
Metcalfe, Ralph W.; Mcmurtry, Patrick A.; Jou, Wen-Huei; Riley, James J.; Givi, Peyman
1988-01-01
The results of direct numerical simulations of chemically reacting turbulent mixing layers are presented. This is an extension of earlier work to a more detailed study of previous three dimensional simulations of cold reacting flows plus the development, validation, and use of codes to simulate chemically reacting shear layers with heat release. Additional analysis of earlier simulations showed good agreement with self similarity theory and laboratory data. Simulations with a two dimensional code including the effects of heat release showed that the rate of chemical product formation, the thickness of the mixing layer, and the amount of mass entrained into the layer all decrease with increasing rates of heat release. Subsequent three dimensional simulations showed similar behavior, in agreement with laboratory observations. Baroclinic torques and thermal expansion in the mixing layer were found to produce changes in the flame vortex structure that act to diffuse the pairing vortices, resulting in a net reduction in vorticity. Previously unexplained anomalies observed in the mean velocity profiles of reacting jets and mixing layers were shown to result from vorticity generation by baroclinic torques.
Photometric study of cometary analogs in the LOSSy laboratory at the University of Bern
NASA Astrophysics Data System (ADS)
Pommerol, A.; Thomas, N.; Jost, B.; Poch, O.
2014-07-01
We have set up the LOSSy laboratory (Laboratory for Outflow Studies of Sublimating Materials) to study the spectro-photometric properties of various analogs of planetary-object surfaces, with a special emphasis on icy samples and their evolution under simulated space conditions. This laboratory is currently equipped with two facilities: the PHIRE-2 radio-goniometer, designed to measure the bidirectional visible reflectance of samples under a wide range of geometries and the SCITEAS simulation chamber, designed to follow the evolution of icy samples subliming under low temperature and low pressure conditions by means of VIS-NIR hyperspectral imaging. We will report on the characterization of cometary analogs using both facilities. We produce these analogs by mixing in various proportions fine-grained ice, mineral and organic matter. Various preparation protocols have been defined to produce different textures of sample. Using the PHIRE-2 radio-goniometer, we are building a catalog of bidirectional reflectance data for various cometary analogs, varying by steps the different parameters susceptible to affect the reflectance phase function. In particular, we have recently upgraded the instrument to be able to characterize in detail the opposition effect by allowing measurements of the reflectance at very low phase angle. This laboratory dataset is intended to be used for the analysis of the data acquired by the OSIRIS imager onboard Rosetta. Using the SCITEAS simulation chamber, we have followed for 30 hours the evolution of a cometary analog placed under secondary vacuum (<10^{-6} mbar) and maintained at low temperature (170-200 K) for more than 30 hours. We analyzed the temporal evolution of the morphology and the photometry of the surface of the sample to identify which processes affect the surfaces of cometary nuclei during sublimation and how they affect their visible and near-infrared surface properties.
2013-04-03
In a laboratory experiment at NASA Jet Propulsion Laboratory, Pasadena, Calif., scientists simulate the atmosphere of Saturn moon Titan. In this picture, molecules of dicyanoacetylene are seen on a special film on a sapphire window.
Schroder, L.J.; Brooks, M.H.; Malo, B.A.; Willoughby, T.C.
1986-01-01
Five intersite comparison studies for the field determination of pH and specific conductance, using simulated-precipitation samples, were conducted by the U.S.G.S. for the National Atmospheric Deposition Program and National Trends Network. These comparisons were performed to estimate the precision of pH and specific conductance determinations made by sampling-site operators. Simulated-precipitation samples were prepared from nitric acid and deionized water. The estimated standard deviation for site-operator determination of pH was 0.25 for pH values ranging from 3.79 to 4.64; the estimated standard deviation for specific conductance was 4.6 microsiemens/cm at 25 C for specific-conductance values ranging from 10.4 to 59.0 microsiemens/cm at 25 C. Performance-audit samples with known analyte concentrations were prepared by the U.S.G.S.and distributed to the National Atmospheric Deposition Program 's Central Analytical Laboratory. The differences between the National Atmospheric Deposition Program and national Trends Network-reported analyte concentrations and known analyte concentrations were calculated, and the bias and precision were determined. For 1983, concentrations of calcium, magnesium, sodium, and chloride were biased at the 99% confidence limit; concentrations of potassium and sulfate were unbiased at the 99% confidence limit. Four analytical laboratories routinely analyzing precipitation were evaluated in their analysis of identical natural- and simulated precipitation samples. Analyte bias for each laboratory was examined using analysis of variance coupled with Duncan 's multiple-range test on data produced by these laboratories, from the analysis of identical simulated-precipitation samples. Analyte precision for each laboratory has been estimated by calculating a pooled variance for each analyte. Interlaboratory comparability results may be used to normalize natural-precipitation chemistry data obtained from two or more of these laboratories. (Author 's abstract)
USDA-ARS?s Scientific Manuscript database
Accurate determination of predicted environmental concentrations (PECs) is a continuing and often elusive goal of pesticide risk assessment. PECs are typically derived using simulation models that depend on laboratory generated data for key input parameters (t1/2, Koc, etc.). Model flexibility in ...
USDA-ARS?s Scientific Manuscript database
Accurate determination of predicted environmental concentrations (PECs) is a continuing and often elusive goal of pesticide risk assessment. PECs are typically derived using simulation models that depend on laboratory generated data for key input parameters (t1/2, Koc, etc.). Model flexibility in ev...
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
Inspired by human forgetfulness – how our brains discard unnecessary data to make room for new information – scientists at the U.S. Department of Energy’s (DOE) Argonne National Laboratory, in collaboration with Brookhaven National Laboratory and three universities, conducted a recent study that combined supercomputer simulation and X-ray characterization of a material that gradually “forgets.”
Performance evaluation of a kinesthetic-tactual display
NASA Technical Reports Server (NTRS)
Jagacinski, R. J.; Flach, J. M.; Gilson, R. D.; Dunn, R. S.
1982-01-01
Simulator studies demonstrated the feasibility of using kinesthetic-tactual (KT) displays for providing collective and cyclic command information, and suggested that KT displays may increase pilot workload capability. A dual-axis laboratory tracking task suggested that beyond reduction in visual scanning, there may be additional sensory or cognitive benefits to the use of multiple sensory modalities. Single-axis laboratory tracking tasks revealed performance with a quickened KT display to be equivalent to performance with a quickened visual display for a low frequency sum-of-sinewaves input. In contrast, an unquickened KT display was inferior to an unquickened visual display. Full scale simulator studies and/or inflight testing are recommended to determine the generality of these results.
NASA Astrophysics Data System (ADS)
Pedro Sánchez, Juan; Sáenz, Jacobo; de la Torre, Luis; Carreras, Carmen; Yuste, Manuel; Heradio, Rubén; Dormido, Sebastián
2016-05-01
This work describes two experiments: "study of the diffraction of light: Fraunhofer approximation" and "the photoelectric effect". Both of them count with a virtual, simulated, version of the experiment as well as with a real one which can be operated remotely. The two previous virtual and remote labs (built using Easy Java(script) Simulations) are integrated in UNILabs, a network of online interactive laboratories based on the free Learning Management System Moodle. In this web environment, students can find not only the virtual and remote labs but also manuals with related theory, the user interface description for each application, and so on.
Ideas in Practice (3): A Simulated Laboratory Experience in Digital Design.
ERIC Educational Resources Information Center
Cleaver, Thomas G.
1988-01-01
Gives an example of the use of a simplified logic simulator in a logic design course. Discusses some problems in logic design classes, commercially available software, and software problems. Describes computer-aided engineering (CAE) software. Lists 14 experiments in the simulated laboratory and presents students' evaluation of the course. (YP)
ERIC Educational Resources Information Center
Whitman, David L.; Terry, Ronald E.
1985-01-01
Demonstrating petroleum engineering concepts in undergraduate laboratories often requires expensive and time-consuming experiments. To eliminate these problems, a graphical simulation technique was developed for junior-level laboratories which illustrate vapor-liquid equilibrium and the use of mathematical modeling. A description of this…
ERIC Educational Resources Information Center
Baltzis, Konstantinos B.; Koukias, Konstantinos D.
2009-01-01
Laboratory-based courses play a significant role in engineering education. Given the role of electronics in engineering and technology, laboratory experiments and circuit simulation IT tools are used in their teaching in several academic institutions. This paper discusses the characteristics and benefits of both methods. The content and structure…
Viability of using energy storage for frequency regulation on power grid
NASA Astrophysics Data System (ADS)
Lim, Y. S.; Hau, L. C.; Loh, K. Y.; Lim, K. Y.; Lyons, P. F.; Taylor, P. C.
2018-05-01
This project is about the development and integration of a real-time network simulator in the laboratory using hardware in the loop (HIL) for the purpose of frequency regulation. Frequency regulation is done using the energy storage system (ESS) and a real-time network test bed developed in the smart energy laboratory in Newcastle University. An IEEE Test System was built in the OPAL-RT network simulator to mimic the power grid with renewable energy sources. The study demonstrates the viability of using an ESS to regulate the frequency under an increased penetration of renewable energy sources.
Williams, Richard M.; Aalseth, C. E.; Brandenberger, J. M.; ...
2017-02-17
Here, this paper describes the generation of 39Ar, via reactor irradiation of potassium carbonate, followed by quantitative analysis (length-compensated proportional counting) to yield two calibration standards that are respectively 50 and 3 times atmospheric background levels. Measurements were performed in Pacific Northwest National Laboratory's shallow underground counting laboratory studying the effect of gas density on beta-transport; these results are compared with simulation. The total expanded uncertainty of the specific activity for the ~50 × 39Ar in P10 standard is 3.6% (k=2).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Williams, Richard M.; Aalseth, C. E.; Brandenberger, J. M.
Here, this paper describes the generation of 39Ar, via reactor irradiation of potassium carbonate, followed by quantitative analysis (length-compensated proportional counting) to yield two calibration standards that are respectively 50 and 3 times atmospheric background levels. Measurements were performed in Pacific Northwest National Laboratory's shallow underground counting laboratory studying the effect of gas density on beta-transport; these results are compared with simulation. The total expanded uncertainty of the specific activity for the ~50 × 39Ar in P10 standard is 3.6% (k=2).
NASA Technical Reports Server (NTRS)
Nusinov, M. D.; Kochnev, V. A.; Chernyak, Y. B.; Kuznetsov, A. V.; Kosolapov, A. I.; Yakovlev, O. I.
1974-01-01
Study of evaporation, condensation and sputtering on the moon can provide information on the same processes on other planets, and reveal details of the formation of the lunar regolith. Simulation methods include vacuum evaporation, laser evaporation, and bubbling gas through melts.
Simulations with Elaborated Worked Example Modeling: Beneficial Effects on Schema Acquisition
ERIC Educational Resources Information Center
Meier, Debra K.; Reinhard, Karl J.; Carter, David O.; Brooks, David W.
2008-01-01
Worked examples have been effective in enhancing learning outcomes, especially with novice learners. Most of this research has been conducted in laboratory settings. This study examined the impact of embedding elaborated worked example modeling in a computer simulation practice activity on learning achievement among 39 undergraduate students…
DOT National Transportation Integrated Search
2007-08-01
This research was conducted to develop and test a personal computer-based study procedure (PCSP) with secondary task loading for use in human factors laboratory experiments in lieu of a driving simulator to test reading time and understanding of traf...
Entrainment in Laboratory Simulations of Cumulus Cloud Flows
NASA Astrophysics Data System (ADS)
Narasimha, R.; Diwan, S.; Subrahmanyam, D.; Sreenivas, K. R.; Bhat, G. S.
2010-12-01
A variety of cumulus cloud flows, including congestus (both shallow bubble and tall tower types), mediocris and fractus have been generated in a water tank by simulating the release of latent heat in real clouds. The simulation is achieved through ohmic heating, injected volumetrically into the flow by applying suitable voltages between diametral cross-sections of starting jets and plumes of electrically conducting fluid (acidified water). Dynamical similarity between atmospheric and laboratory cloud flows is achieved by duplicating values of an appropriate non-dimensional heat release number. Velocity measurements, made by laser instrumentation, show that the Taylor entrainment coefficient generally increases just above the level of commencement of heat injection (corresponding to condensation level in the real cloud). Subsequently the coefficient reaches a maximum before declining to the very low values that characterize tall cumulus towers. The experiments also simulate the protected core of real clouds. Cumulus Congestus : Atmospheric cloud (left), simulated laboratory cloud (right). Panels below show respectively total heat injected and vertical profile of heating in the laboratory cloud.
Simulation of General Physics laboratory exercise
NASA Astrophysics Data System (ADS)
Aceituno, P.; Hernández-Aceituno, J.; Hernández-Cabrera, A.
2015-01-01
Laboratory exercises are an important part of general Physics teaching, both during the last years of high school and the first year of college education. Due to the need to acquire enough laboratory equipment for all the students, and the widespread access to computers rooms in teaching, we propose the development of computer simulated laboratory exercises. A representative exercise in general Physics is the calculation of the gravity acceleration value, through the free fall motion of a metal ball. Using a model of the real exercise, we have developed an interactive system which allows students to alter the starting height of the ball to obtain different fall times. The simulation was programmed in ActionScript 3, so that it can be freely executed in any operative system; to ensure the accuracy of the calculations, all the input parameters of the simulations were modelled using digital measurement units, and to allow a statistical management of the resulting data, measurement errors are simulated through limited randomization.
3D-PTV around Operational Wind Turbines
NASA Astrophysics Data System (ADS)
Brownstein, Ian; Dabiri, John
2016-11-01
Laboratory studies and numerical simulations of wind turbines are typically constrained in how they can inform operational turbine behavior. Laboratory experiments are usually unable to match both pertinent parameters of full-scale wind turbines, the Reynolds number (Re) and tip speed ratio, using scaled-down models. Additionally, numerical simulations of the flow around wind turbines are constrained by the large domain size and high Re that need to be simulated. When these simulations are preformed, turbine geometry is typically simplified resulting in flow structures near the rotor not being well resolved. In order to bypass these limitations, a quantitative flow visualization method was developed to take in situ measurements of the flow around wind turbines at the Field Laboratory for Optimized Wind Energy (FLOWE) in Lancaster, CA. The apparatus constructed was able to seed an approximately 9m x 9m x 5m volume in the wake of the turbine using artificial snow. Quantitative measurements were obtained by tracking the evolution of the artificial snow using a four camera setup. The methodology for calibrating and collecting data, as well as preliminary results detailing the flow around a 2kW vertical-axis wind turbine (VAWT), will be presented.
Wear simulation of resin composites and the relationship to clinical wear.
Barkmeier, Wayne W; Latta, Mark A; Erickson, Robert L; Wilwerding, Terry M
2008-01-01
This study used a new generalized wear model to examine the relationship between wear simulation and the clinical wear of two resin composites. Ten specimens each of P50 and Z100, were subjected to 100,000, 400,000 and 800,000 cycles in a spring-loaded piston-type wear simulator. Wear was generated using flat, cylindrically-shaped stainless steel antagonists on the resin composites, which were placed in custom stainless steel fixtures. A slurry of polymethyl methacrylate beads was used as the abrasive media. Wear was determined using profilometry, and the parameters examined included volume loss (mm3), maximum depth (microm), mean maximum depth (microm) and mean depth (microm). Statistical analysis of the laboratory wear data using ANOVA and Tukey's post hoc test showed a significant difference (p<0.05) for wear between the two materials and the number of cycles. Mean maximum wear (microm) values (100K--P50--11.5 +/- 1.8; Z100--4.9 +/- 1.0; 400K--P50--17.2 +/- 2.7; Z100--6.0 +/- 1.7; 800K--P50--20.5 +/- 4.6; Z100--9.6 +/- 2.5) were used for comparisons with clinical data. Previous clinical studies of P50 and Z100 were used to examine the relationship between laboratory and clinical wear. Linear regression analysis was used to predict laboratory and clinical wear rates. The laboratory wear rate for P50 was 1.3 microm/100K cycles and the rate for Z100 was 0.7 microm/100K cycles. The clinical wear rates for P50 and Z100 were 8.3 microm/year and 4.0 microm/year, respectively. The ratio of wear rates of P50 to Z100 for wear simulation was 1.9 and the ratio of P50 to Z100 for clinical rates was 2.1. These ratios showed good agreement between the relative wear rates of laboratory and clinical wear. For the two composite materials examined, this new simulation model appears to be effective for evaluating the relative wear of resin composites.
Cruise Stage Testing for Mars Science Laboratory
2010-09-02
Testing of the cruise stage for NASA Mars Science Laboratory in August 2010 included a session in a facility that simulates the environment found in interplanetary space. Spacecraft technicians at JPL prepare a space-simulation test.
Feasibility Study of SSTO Base Heating Simulation in Pulsed-Type Facilities
NASA Technical Reports Server (NTRS)
Park, Chung Sik; Sharma, Surendra; Edwards, Thomas A. (Technical Monitor)
1995-01-01
A laboratory simulation of the base heating environment of the proposed reusable Single-Stage-To-Orbit vehicle during its ascent flight was proposed. The rocket engine produces CO2 and H2, which are the main combustible components of the exhaust effluent. The burning of these species, known as afterburning, enhances the base region gas temperature as well as the base heating. To determine the heat flux on the SSTO vehicle, current simulation focuses on the thermochemistry of the afterburning, thermophysical properties of the base region gas, and ensuing radiation from the gas. By extrapolating from the Saturn flight data, the Damkohler number for the afterburning of SSTO vehicle is estimated to be of the order of 10. The limitations on the material strengths limit the laboratory simulation of the flight Damkohler number as well as other flow parameters. A plan is presented in impulse facilities using miniature rocket engines which generate the simulated rocket plume by electric ally-heating a H2/CO2 mixture.
2D Implosion Simulations with a Kinetic Particle Code
NASA Astrophysics Data System (ADS)
Sagert, Irina; Even, Wesley; Strother, Terrance
2017-10-01
Many problems in laboratory and plasma physics are subject to flows that move between the continuum and the kinetic regime. We discuss two-dimensional (2D) implosion simulations that were performed using a Monte Carlo kinetic particle code. The application of kinetic transport theory is motivated, in part, by the occurrence of non-equilibrium effects in inertial confinement fusion (ICF) capsule implosions, which cannot be fully captured by hydrodynamics simulations. Kinetic methods, on the other hand, are able to describe both, continuum and rarefied flows. We perform simple 2D disk implosion simulations using one particle species and compare the results to simulations with the hydrodynamics code RAGE. The impact of the particle mean-free-path on the implosion is also explored. In a second study, we focus on the formation of fluid instabilities from induced perturbations. I.S. acknowledges support through the Director's fellowship from Los Alamos National Laboratory. This research used resources provided by the LANL Institutional Computing Program.
NASA Astrophysics Data System (ADS)
Miller, M. A.; Miller, N. L.; Sale, M. J.; Springer, E. P.; Wesely, M. L.; Bashford, K. E.; Conrad, M. E.; Costigan, K. R.; Kemball-Cook, S.; King, A. W.; Klazura, G. E.; Lesht, B. M.; Machavaram, M. V.; Sultan, M.; Song, J.; Washington-Allen, R.
2001-12-01
A multi-laboratory Department of Energy (DOE) team (Argonne National Laboratory, Brookhaven National Laboratory, Los Alamos National Laboratory, Lawrence Berkeley National Laboratory, Oak Ridge National Laboratory) has begun an investigation of hydrometeorological processes at the Whitewater subbasin of the Walnut River Watershed in Kansas. The Whitewater sub-basin is viewed as a DOE long-term hydrologic research watershed and resides within the well-instrumented Atmospheric Radiation Measurement/Cloud Radiation Atmosphere Testbed (ARM/CART) and the proposed Arkansas-Red River regional hydrologic testbed. The focus of this study is the development and evaluation of coupled regional to watershed scale models that simulate atmospheric, land surface, and hydrologic processes as systems with linkages and feedback mechanisms. This pilot is the precursor to the proposed DOE Water Cycle Dynamics Prediction Program. An important new element is the introduction of water isotope budget equations into mesoscale and hydrologic modeling. Two overarching hypotheses are part of this pilot study: (1) Can the predictability of the regional water balance be improved using high-resolution model simulations that are constrained and validated using new water isotope and hydrospheric water measurements? (2) Can water isotopic tracers be used to segregate different pathways through the water cycle and predict a change in regional climate patterns? Initial results of the pilot will be presented along with a description and copies of the proposed DOE Water Cycle Dynamics Prediction Program.
Simulations of the National Ignition Facility Opacity Sample
NASA Astrophysics Data System (ADS)
Martin, M. E.; London, R. A.; Heeter, R. F.; Dodd, E. S.; Devolder, B. G.; Opachich, Y. P.; Liedahl, D. A.; Perry, T. S.
2017-10-01
A platform to study the opacity of high temperature materials at the National Ignition Facility has been developed. Experiments to study the opacity of materials relevant to inertial confinement fusion and stellar astrophysics are being conducted. The initial NIF experiments are focused on reaching the same plasma conditions (T >150 eV and Ne >= 7 ×1021 cm-3) , for iron, as those achieved in previous experiments at Sandia National Laboratories' (SNL) Z-facility which have shown discrepancies between opacity theory and experiment. We developed a methodology, using 1D HYDRA simulations, to study the effects of tamper thickness on the conditions of iron-magnesium samples. We heat the sample using an x-ray drive from 2D LASNEX hohlraum simulations. We also use this methodology to predict sample uniformity and expansion for comparison with experimental data. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. Lawrence Livermore National Security, LLC.
Middleware Trade Study for NASA Domain
NASA Technical Reports Server (NTRS)
Bowman, Dan
2007-01-01
This presentation presents preliminary results of a trade study designed to assess three distributed simulation middleware technologies for support of the NASA Constellation Distributed Space Exploration Simulation (DSES) project and Test and Verification Distributed System Integration Laboratory (DSIL). The technologies are: the High Level Architecture (HLA), the Test and Training Enabling Architecture (TENA), and an XML-based variant of Distributed Interactive Simulation (DIS-XML) coupled with the Extensible Messaging and Presence Protocol (XMPP). According to the criteria and weights determined in this study, HLA scores better than the other two for DSES as well as the DSIL
Wind driven erosion and the effects of particulate electrification
NASA Astrophysics Data System (ADS)
Merrison, J. P.; Bak, E.; Finster, K.; Gunnlaugsson, H. P.; Holstein-Rathlou, C.; Knak Jensen, S.; Nørnberg, P.; Rasmussen, K. R.
2012-09-01
Several related aspects of Aeolian activity are presently being studied in the laboratory, the most recent advances in this field will be presented. These include simulating wind driven erosion in the laboratory, quantifying erosion rates and the study of mineral change due to mechanical activation. Also advances in our understanding of the electrification of sand/dust particles is being made and how this phenomenon affects their behavior.
ERIC Educational Resources Information Center
Lefkos, Ioannis; Psillos, Dimitris; Hatzikraniotis, Euripides
2011-01-01
Background and purpose: The aim of this study was to explore the effect of investigative activities with manipulations in a virtual laboratory on students' ability to design experiments. Sample: Fourteen students in a lower secondary school in Greece attended a teaching sequence on thermal phenomena based on the use of information and…
Reliability of analog quantum simulation
NASA Astrophysics Data System (ADS)
Sarovar, Mohan; Zhang, Jun; Zeng, Lishan
Analog quantum simulators (AQS) will likely be the first nontrivial application of quantum technology for predictive simulation. However, there remain questions regarding the degree of confidence that can be placed in the results of AQS since they do not naturally incorporate error correction. We formalize the notion of AQS reliability to calibration errors by determining sensitivity of AQS outputs to underlying parameters, and formulate conditions for robust simulation. Our approach connects to the notion of parameter space compression in statistical physics and naturally reveals the importance of model symmetries in dictating the robust properties. This work was supported by the Laboratory Directed Research and Development program at Sandia National Laboratories. Sandia National Laboratories is a multi-mission laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the United States Department of Energy's National Nuclear Security Administration under Contract No. DE-AC04-94AL85000.
Advances in Interstellar and Planetary Laboratory Astrophysics with Ames’ COSmIC Facility
NASA Astrophysics Data System (ADS)
Salama, Farid; Sciamma-O'Brien, Ella; Bejaoui, Salma
2017-06-01
The COSmIC facility was developed at NASA Ames to study interstellar, circumstellar and planetary analogs in the laboratory [1]. COSmIC stands for “Cosmic Simulation Chamber” and is dedicated to the study of neutral and ionized molecules and nanoparticles under the low temperature and high vacuum conditions that are required to simulate space environments. COSmIC integrates a variety of instruments that allow forming, processing and monitoring simulated space conditions in the laboratory. It is composed of a Pulsed Discharge Nozzle (PDN) expansion that generates a plasma in a free supersonic jet expansion coupled to high-sensitivity, complementary in situ diagnostics tools, used for the detection and characterization of the species present in the expansion: a Cavity Ring Down Spectroscopy (CRDS) and fluorescence spectroscopy systems for photonic detection and a Reflectron Time-Of-Flight Mass Spectrometer (ReTOF-MS) for mass detection [2].Recent advances achieved in laboratory astrophysics using COSmIC will be presented, in particular the advances that have been achieved in the domain of the diffuse interstellar bands (DIBs) [3] and in monitoring, in the laboratory, the formation of dust grains and aerosols from their gas-phase molecular precursors in environments as varied as circumstellar outflows [4] and planetary atmospheres [5, 6]. Plans for future laboratory experiments on cosmic molecules and grains in the growing field of laboratory astrophysics (NIR-MIR CRDS, Laser Induced Fluorescence spectra of cosmic molecule analogs and the laser induced incandescence spectra of cosmic grain analogs will also be addressed as well as the implications of the on-going studies for astronomy.References: [1] Salama F., In Organic Matter in Space, IAU S251, Kwok & Sandford eds.CUP, 4, 357 (2008).[2] Ricketts C., Contreras C., Walker, R., Salama F., Int. J. Mass Spec, 300, 26 (2011)[3] Salama F., Galazutdinov G., Krelowski J., Biennier L., Beletsky Y., In-Ok Song, The Astrophys. J., 728, 154 (2011)[4] Cesar Contreras & Farid Salama, The Astrophys. J. Suppl. Ser., 208, 6 (2013)[5] Sciamma-O'Brien E., Ricketts C., and Salama F. Icarus, 243, 325 (2014)[6] Sciamma-O'Brien E., Upton K. and Salama F. Icarus, in press (2017)
High Fidelity Simulation of Atomization in Diesel Engine Sprays
2015-09-01
ARL-RP-0555 ● SEP 2015 US Army Research Laboratory High Fidelity Simulation of Atomization in Diesel Engine Sprays by L Bravo...ARL-RP-0555 ● SEP 2015 US Army Research Laboratory High Fidelity Simulation of Atomization in Diesel Engine Sprays by L...Simulation of Atomization in Diesel Engine Sprays 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) L Bravo, CB Ivey, D
Kuselman, Ilya; Pennecchi, Francesca; Epstein, Malka; Fajgelj, Ales; Ellison, Stephen L R
2014-12-01
Monte Carlo simulation of expert judgments on human errors in a chemical analysis was used for determination of distributions of the error quantification scores (scores of likelihood and severity, and scores of effectiveness of a laboratory quality system in prevention of the errors). The simulation was based on modeling of an expert behavior: confident, reasonably doubting and irresolute expert judgments were taken into account by means of different probability mass functions (pmfs). As a case study, 36 scenarios of human errors which may occur in elemental analysis of geological samples by ICP-MS were examined. Characteristics of the score distributions for three pmfs of an expert behavior were compared. Variability of the scores, as standard deviation of the simulated score values from the distribution mean, was used for assessment of the score robustness. A range of the score values, calculated directly from elicited data and simulated by a Monte Carlo method for different pmfs, was also discussed from the robustness point of view. It was shown that robustness of the scores, obtained in the case study, can be assessed as satisfactory for the quality risk management and improvement of a laboratory quality system against human errors. Copyright © 2014 Elsevier B.V. All rights reserved.
A Demonstration of Delay and Constructive Modeling Effects in Distributed Interactive Simulation.
1998-02-01
with the Armstrong Laboratory Design Technology Branch, Veda Incorporated, and Science Applications International Corporation (SAIC). SAIC was working...The authors express special thanks to Mr. Dave O’Quinn of Veda Incorporated who provided quality simulation engineering support, and to Mr. David...platform employed in the study was the Engineering Design Simulator (EDSM) shown in Figure 3. Developed by Veda Inc., the EDSM is a single-seat
NASA Technical Reports Server (NTRS)
Steffes, Paul G.
1989-01-01
Accurate data on microwave and millimeter-wave properties of potential planetary atmospheric constituents is critical for the proper interpretation of radio occultation measurements, and of radio astronomical observations of both continuum and spectral line emissions. Such data is also needed to correct for atmospheric effects on radar studies of surface reflectivity. Since the refractive and absorptive properties of atmospheric constituents often vary drastically from theoretically-predicted profiles, especially under the extreme conditions characteristic of the planetary atmosphere, laboratory measurements under simulated planetary conditions are required. This paper reviews the instrumentation and techniques used for laboratory measurement of the refractivity and absorptivity of atmospheric constituents at wavelengths longward of 1 mm, under simulated planetary conditions (temperature, pressure, and broadening gases). Techniques for measuring both gases and condensates are considered. Also reviewed are the relative accuracies of the various techniques. Laboratory measurements are reviewed which have already been made, and additional measurements which are needed for interpretation of data from Venus and the outer planets, are highlighted.
Back to the future with hands-on science: students' perceptions of learning anatomy and physiology.
Johnston, Amy Nicole Burne; McAllister, Margaret
2008-09-01
This article examines student perceptions of learning related to anatomy and physiology in a bachelor of nursing program. One strategy to teach the sciences is simulated learning, a technology that offers exciting potential. Virtual environments for laboratory learning may offer numerous benefits: teachers can convey information to a larger group of students, reducing the need for small laboratory classes; less equipment is required, thus containing ongoing costs; and students can learn in their own time and place. However, simulated learning may also diminish access to the teacher-student relationship and the opportunity for guided practice and guided linking of theory with practice. Without this hands-on experience, there is a risk that students will not engage as effectively, and thus conceptual learning and the development of critical thinking skills are diminished. However, student perceptions of these learning experiences are largely unknown. Thus, this study examined students' perceptions of anatomy and physiology laboratory experiences and the importance they placed on hands-on experience in laboratory settings.
NASA Astrophysics Data System (ADS)
Thangavelautham, J.; Asphaug, E.; Schwartz, S.
2017-02-01
Our work has identified the use of on-orbit centrifuge science laboratories as a key enabler towards low-cost, fast-track physical simulation of off-world environments for future planetary science missions.
An Authentic RFLP Lab for High School or College Biology Students.
ERIC Educational Resources Information Center
Guilfoile, Patrick G.; Plum, Stephen
1998-01-01
Explains how students can perform an alternative authentic DNA fingerprinting analysis. Presents restriction fragment length polymorphism (RFLP) analysis and can serve as a simulated molecular epidemiology laboratory or as a simulated forensic laboratory exercise. (DDR)
Cremonini, Valeria; Ferri, Paola; Artioli, Giovanna; Sarli, Leopoldo; Piccioni, Enrico; Rubbi, Ivan
2015-01-01
Student satisfaction is an important element of the effectiveness of clinical placement, but there is little consensus in the literature as to the preferred model of clinical experience for undergraduate nursing students. The aim of this study was assess, for each academic year, students' perception of the roles of nurse teachers (NT) and clinical nurse supervisors (CNS) who perform tutoring in both apprenticeship and laboratories and to identify and evaluate students' satisfaction with the environment of clinical learning. This analytic cross-sectional study was conducted in a sample of 173 nursing students in the Northern Italy. The research instrument used is the Clinical learning environment, supervision and nurse teacher (CLES+T) evaluation scale. Data were statistically analysed. 94% of our sample answered questionnaires. Students expressed a higher level of satisfaction with their training experiences. The highest mean value was in the sub-dimension "Pedagogical atmosphere on the ward". Third year students expressed higher satisfaction levels in their relationship with the CNS and lower satisfaction levels in their relationship with the NT. This result may be due to the educational model that is adopted in the course, in which the simulation laboratory didactic activities of the third year are conducted by CNS, who also supervises experiences of clinical learning in the clinical practice. The main finding in this study was that the students' satisfaction with the supervisory relationship and the role of NT depend on how supervision in the clinical practice and in the simulation laboratory is organized.
Laboratory experiments were conducted to simulate radiopollutant effluents released to the atmosphere from two standard-design nuclear power plants. The main objective of the study was to compare the dispersion in the wakes of the plants with that in a simulated atmospheric bound...
ERIC Educational Resources Information Center
Shegog, Ross; Lazarus, Melanie M.; Murray, Nancy G.; Diamond, Pamela M.; Sessions, Nathalie; Zsigmond, Eva
2012-01-01
The transgenic mouse model is useful for studying the causes and potential cures for human genetic diseases. Exposing high school biology students to laboratory experience in developing transgenic animal models is logistically prohibitive. Computer-based simulation, however, offers this potential in addition to advantages of fidelity and reach.…
Knowledge Retention for Computer Simulations: A study comparing virtual and hands-on laboratories
NASA Astrophysics Data System (ADS)
Croom, John R., III
The use of virtual laboratories has the potential to change physics education. These low-cost, interactive computer activities interest students, allow for easy setup, and give educators a way to teach laboratory based online classes. This study investigated whether virtual laboratories could replace traditional hands-on laboratories and whether students could retain the same long-term knowledge in virtual laboratories as compared to hands-on laboratories. This study is a quantitative quasi-experiment that used a multiple posttest design to determine if students using virtual laboratories would retain the same knowledge as students who performed hands-on laboratories after 9 weeks. The study was composed of 336 students from 14 school districts. Students had their performances on the laboratories and their retention of the laboratories compared to a series of factors that might have affected their retention using a pretest and two posttests, which were compared using a t test. The results showed no significant difference in short-term learning between the hands-on laboratory groups and virtual laboratory groups. There was, however, a significant difference (p = .005) between the groups in long-term retention; students in the hands-on laboratory groups retained more information than those in the virtual laboratory groups. These results suggest that long-term learning is enhanced when a laboratory contains a hands-on component. Finally, the results showed that both groups of students felt their particular laboratory style was superior to the alternative method. The findings of this study can be used to improve the integration of virtual laboratories into science curriculum.
NASA Technical Reports Server (NTRS)
Kerr, James R.; Haskins, James F.
1987-01-01
Advanced composites will play a key role in the development of the technology for the design and fabrication of future supersonic vehicles. However, incorporating the material into vehicle usage is contingent on accelerating the demonstration of service capacity and design technology. Because of the added material complexity and lack of extensive data, laboratory replication of the flight service will provide the most rapid method to document the airworthiness of advanced composite systems. Consequently, a laboratory program was conducted to determine the time-temperature-stress capabilities of several high temperature composites. Tests included were thermal aging, environmental aging, fatigue, creep, fracture, tensile, and real-time flight simulation exposure. The program had two phases. The first included all the material property determinations and aging and simulation exposures up through 10,000 hours. The second continued these tests up to 50,000 cumulative hours. This report presents the results of the Phase 1 baseline and 10,000-hr aging and flight simulation studies, the Phase 2 50,000-hr aging studies, and the Phase 2 flight simulation tests, some of which extended to almost 40,000 hours.
Defense Waste Processing Facility Simulant Chemical Processing Cell Studies for Sludge Batch 9
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, Tara E.; Newell, J. David; Woodham, Wesley H.
The Savannah River National Laboratory (SRNL) received a technical task request from Defense Waste Processing Facility (DWPF) and Saltstone Engineering to perform simulant tests to support the qualification of Sludge Batch 9 (SB9) and to develop the flowsheet for SB9 in the DWPF. These efforts pertained to the DWPF Chemical Process Cell (CPC). CPC experiments were performed using SB9 simulant (SB9A) to qualify SB9 for sludge-only and coupled processing using the nitric-formic flowsheet in the DWPF. Two simulant batches were prepared, one representing SB8 Tank 40H and another representing SB9 Tank 51H. The simulant used for SB9 qualification testing wasmore » prepared by blending the SB8 Tank 40H and SB9 Tank 51H simulants. The blended simulant is referred to as SB9A. Eleven CPC experiments were run with an acid stoichiometry ranging between 105% and 145% of the Koopman minimum acid equation (KMA), which is equivalent to 109.7% and 151.5% of the Hsu minimum acid factor. Three runs were performed in the 1L laboratory scale setup, whereas the remainder were in the 4L laboratory scale setup. Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME) cycles were performed on nine of the eleven. The other two were SRAT cycles only. One coupled flowsheet and one extended run were performed for SRAT and SME processing. Samples of the condensate, sludge, and off-gas were taken to monitor the chemistry of the CPC experiments.« less
Akchata, Suman; Lavanya, K; Shivanand, Bhushan
2017-01-01
Context: Decontamination of various working surfaces with sodium pertechnetate minor spillage is essential for maintaining good radiation safety practices as well as for regulatory compliance. Aim: To observe the influences of decontaminating agents and swipe materials on different type of surfaces used in nuclear medicine laboratory work area wet spilled with 99m-technetium (99mTc) sodium pertechnetate. Settings and Design: Lab-simulated working surface materials. Experimental study design. Materials and Methods: Direct decontamination method on dust-free lab simulated new working surfaces [stainless steel, polyvinyl chloride (PVC), Perspex, resin] using four decontaminating agents [tap water, soap water (SW), Radiacwash, and spirit] with four different swipe material [cotton, tissue paper (TP), Whatman paper (WP), adsorbent sheet (AS)] was taken 10 samples (n = 10) for each group. Statistical Analysis: Parametric test two-way analysis of variance is used with significance level of 0.005, was used to evaluate statistical differences between different group of decontaminating agent and swipe material, and the results are expressed in mean ± SD. Results: Decontamination factor is calculated after five cleaning for each group. A total of 160 samples result calculated using four decontaminating agent (tap water, SW, Radiacwash, and spirit), four swipe material (cotton, TP, WP, and AS) for commonly used surface (stainless steel, PVC, Perspex, resin) using direct method by 10 samples (n = 10) for each group. Conclusions: Tap water is the best decontaminating agent compared with SW, Radiac wash and spirit for the laboratory simulated stainless steel, PVC, and Perspex surface material, whereas in case of resin surface material, SW decontaminating agent is showing better effectiveness. Cotton is the best swipe material compared to WP-1, AS and TP for the stainless steel, PVC, Perspex, and resin laboratory simulated surface materials. Perspex and stainless steel are the most suitable and recommended laboratory surface material compared to PVC and resin in nuclear medicine. Radiacwash may show better result for 99mTc labelled product and other radionuclide contamination on the laboratory working surface area. PMID:28680198
Recent Progresses in Laboratory Astrophysics with Ames’ COSmIC Facility
NASA Astrophysics Data System (ADS)
Salama, Farid; Contreras, Cesar; Sciamma-O'Brien, Ella; Bejaoui, Salma
2016-06-01
We present and discuss the characteristics and the capabilities of the laboratory facility, COSmIC, that was developed at NASA Ames to generate, process and analyze interstellar, circumstellar and planetary analogs in the laboratory [1]. COSmIC stands for “Cosmic Simulation Chamber” and is dedicated to the study of neutral and ionized molecules and nano particles under the low temperature and high vacuum conditions that are required to simulate space environments. COSmIC integrates a variety of state-of-the-art instruments that allow forming, processing and monitoring simulated space conditions for planetary, circumstellar and interstellar materials in the laboratory. COSmIC is composed of a Pulsed Discharge Nozzle (PDN) expansion that generates a plasma in free supersonic jet expansion coupled to two high-sensitivity, complementary in situ diagnostics: a Cavity Ring Down Spectroscopy (CRDS) and laser induced fluorescence (LIF) systems for photonic detection and a Reflectron Time-Of-Flight Mass Spectrometer (ReTOF-MS) for mass detection [2].Recent laboratory results that were obtained using COSmIC will be presented, in particular the progress that has been achieved in the domain of the diffuse interstellar bands (DIBs) [3] and in monitoring, in the laboratory, the formation of dust grains and aerosols from their gas-phase molecular precursors in environments as varied as stellar/circumstellar outflows [4] and planetary atmospheres [5]. Plans for future, next generation, laboratory experiments on cosmic molecules and grains in the growing field of laboratory astrophysics will also be addressed as well as the implications of the current studies for astronomy.References: [1] Salama F., In Organic Matter in Space, IAU Symposium 251, Kwok & Sandford Eds.Cambridge University Press, Vol. 4, S251, p. 357 (2008) and references therein.[2] Ricketts C., Contreras C., Walker, R., Salama F., Int. J. Mass Spec, 300, 26 (2011)[3] Salama F., Galazutdinov G., Krelowski J., Biennier L., Beletsky Y., In-Ok Song, The Astrophys. J., 728, 154 (2011)[4] Cesar Contreras and Farid Salama, The Astrophys. J. Suppl. Ser., 208, 6 (2013)[5] Sciamma-O'Brien E., Ricketts C., and Salama F. Icarus, 243, 325 (2014)Acknowledgements: The authors acknowledge the support of NASA SMD.
Methods for Analysis and Simulation of Ballistic Impact
2017-04-01
ARL-RP-0597 ● Apr 2017 US Army Research Laboratory Methods for Analysis and Simulation of Ballistic Impact by John D Clayton...Laboratory Methods for Analysis and Simulation of Ballistic Impact by John D Clayton Weapons and Materials Research Directorate, ARL...analytical, and numerical methods of ballistics research . Similar lengthy references dealing with pertinent aspects include [8, 9]. In contrast, the
NASA Astrophysics Data System (ADS)
Breen, M.; O'Donovan, A.; Murphy, M. D.; Delaney, F.; Hill, M.; Sullivan, P. D. O.
2016-03-01
The aim of this paper was to develop a virtual laboratory simulation platform of the National Building Retrofit Test-bed at the Cork Institute of Technology, Ireland. The building in question is a low-energy retrofit which is provided with electricity by renewable systems including photovoltaics and wind. It can be thought of as a living laboratory, as a number of internal and external building factors are recorded at regular intervals during human occupation. The analysis carried out in this paper demonstrated that, for the period from April to September 2015, the electricity provided by the renewable systems did not consistently match the building’s electricity requirements due to differing load profiles. It was concluded that the use of load shifting techniques may help to increase the percentage of renewable energy utilisation.
Sensitivity of Polar Stratospheric Ozone Loss to Uncertainties in Chemical Reaction Kinetics
NASA Technical Reports Server (NTRS)
Kawa, S. Randolph; Stolarski, Richard S.; Douglass, Anne R.; Newman, Paul A.
2008-01-01
Several recent observational and laboratory studies of processes involved in polar stratospheric ozone loss have prompted a reexamination of aspect of out understanding for this key indicator of global change. To a large extent, our confidence in understanding and projecting changes in polar and global ozone is based on our ability to to simulate these process in numerical models of chemistry and transport. These models depend on laboratory-measured kinetic reaction rates and photlysis cross section to simulate molecular interactions. In this study we use a simple box-model scenario for Antarctic ozone to estimate the uncertainty in loss attributable to known reaction kinetic uncertainties. Following the method of earlier work, rates and uncertainties from the latest laboratory evaluation are applied in random combinations. We determine the key reaction and rates contributing the largest potential errors and compare the results to observations to evaluate which combinations are consistent with atmospheric data. Implications for our theoretical and practical understanding of polar ozone loss will be assessed.
DSMC Studies of the Richtmyer-Meshkov Instability
NASA Astrophysics Data System (ADS)
Gallis, M. A.; Koehler, T. P.; Torczynski, J. R.
2014-11-01
A new exascale-capable Direct Simulation Monte Carlo (DSMC) code, SPARTA, developed to be highly efficient on massively parallel computers, has extended the applicability of DSMC to challenging, transient three-dimensional problems in the continuum regime. Because DSMC inherently accounts for compressibility, viscosity, and diffusivity, it has the potential to improve the understanding of the mechanisms responsible for hydrodynamic instabilities. Here, the Richtmyer-Meshkov instability at the interface between two gases was studied parametrically using SPARTA. Simulations performed on Sequoia, an IBM Blue Gene/Q supercomputer at Lawrence Livermore National Laboratory, are used to investigate various Atwood numbers (0.33-0.94) and Mach numbers (1.2-12.0) for two-dimensional and three-dimensional perturbations. Comparisons with theoretical predictions demonstrate that DSMC accurately predicts the early-time growth of the instability. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.
NASA Technical Reports Server (NTRS)
Martinez, Debbie; Davidson, Paul C.; Kenney, P. Sean; Hutchinson, Brian K.
2004-01-01
The Flight Simulation and Software Branch (FSSB) at NASA Langley Research Center (LaRC) maintains the unique national asset identified as the Transport Research Facility (TRF). The TRF is a group of facilities and integration laboratories utilized to support the LaRC's simulation-to-flight concept. This concept incorporates common software, hardware, and processes for both groundbased flight simulators and LaRC s B-757-200 flying laboratory identified as the Airborne Research Integrated Experiments System (ARIES). These assets provide Government, industry, and academia with an efficient way to develop and test new technology concepts to enhance the capacity, safety, and operational needs of the ever-changing national airspace system. The integration of the TRF enables a smooth continuous flow of the research from simulation to actual flight test.
Prabhakaran, Priya M; Sheeba, Vasu
2014-10-01
Recent studies under semi-natural conditions have revealed various unique features of activity/rest rhythms in Drosophilids that differ from those under standard laboratory conditions. An additional afternoon peak (A-peak) has been reported for Drosophila melanogaster and another species D. malerkotliana while D. ananassae exhibited mostly unimodal diurnal activity. To tease apart the role of light and temperature in mediating these species-specific behaviours of four Drosophilid species D. melanogaster, D. malerkotliana, D. ananassae, and Zaprionus indianus we simulated gradual natural light and/or temperature cycles conditions in laboratory. The pattern observed under semi-natural conditions could be reproduced in the laboratory for all the species under a variety of simulated conditions. D. melanogaster and D. malerkotliana showed similar patterns where as D. ananassae consistently exhibited predominant morning activity under almost all regimes. Z. indianus showed clearly rhythmic activity mostly when temperature cycles were provided. We find that gradually changing light intensities reaching a sufficiently high peak value can elicit A-peak in D. melanogaster, D. malerkotliana, and D. ananassae even at mild ambient temperature. Furthermore, we show that high mid-day temperature could induce A-peak in all species even under constant light conditions suggesting that this A-peak is likely to be a stress response.
Kushniruk, A; Nohr, C; Jensen, S; Borycki, E M
2013-01-01
The objective of this paper is to explore human factors approaches to understanding the use of health information technology (HIT) by extending usability engineering approaches to include analysis of the impact of clinical context through use of clinical simulations. Methods discussed are considered on a continuum from traditional laboratory-based usability testing to clinical simulations. Clinical simulations can be conducted in a simulation laboratory and they can also be conducted in real-world settings. The clinical simulation approach attempts to bring the dimension of clinical context into stronger focus. This involves testing of systems with representative users doing representative tasks, in representative settings/environments. Application of methods where realistic clinical scenarios are used to drive the study of users interacting with systems under realistic conditions and settings can lead to identification of problems and issues with systems that may not be detected using traditional usability engineering methods. In conducting such studies, careful consideration is needed in creating ecologically valid test scenarios. The evidence obtained from such evaluation can be used to improve both the usability and safety of HIT. In addition, recent work has shown that clinical simulations, in particular those conducted in-situ, can lead to considerable benefits when compared to the costs of running such studies. In order to bring context of use into the testing of HIT, clinical simulation, involving observing representative users carrying out tasks in representative settings, holds considerable promise.
Field and Laboratory Studies for Increasing the Intrinsic Reward Value in Navy Jobs and Careers.
1975-08-31
Cabe, P.A. The relation be- tween embedded figures test performance and simulator behavior. Journal of Applied Psychology , 1969, 5_3, 253-254. Blood... Psychology , 1973, 99, 137-139. Moses, J.L. Selecting vigilant types: Predicting vigilance per- formance by means of a field dependence test ...Laboratory Studies for Increasing the Intrinsic Reward Value in Navy Jobs and Careers Gerald V. Barrett Faye H. Dambrot Department of Psychology
NASA Technical Reports Server (NTRS)
Aguilar, R.
2006-01-01
Pratt & Whitney Rocketdyne has developed a real-time engine/vehicle system integrated health management laboratory, or testbed, for developing and testing health management system concepts. This laboratory simulates components of an integrated system such as the rocket engine, rocket engine controller, vehicle or test controller, as well as a health management computer on separate general purpose computers. These general purpose computers can be replaced with more realistic components such as actual electronic controllers and valve actuators for hardware-in-the-loop simulation. Various engine configurations and propellant combinations are available. Fault or failure insertion capability on-the-fly using direct memory insertion from a user console is used to test system detection and response. The laboratory is currently capable of simulating the flow-path of a single rocket engine but work is underway to include structural and multiengine simulation capability as well as a dedicated data acquisition system. The ultimate goal is to simulate as accurately and realistically as possible the environment in which the health management system will operate including noise, dynamic response of the engine/engine controller, sensor time delays, and asynchronous operation of the various components. The rationale for the laboratory is also discussed including limited alternatives for demonstrating the effectiveness and safety of a flight system.
Scientific Assistant Virtual Laboratory (SAVL)
NASA Astrophysics Data System (ADS)
Alaghband, Gita; Fardi, Hamid; Gnabasik, David
2007-03-01
The Scientific Assistant Virtual Laboratory (SAVL) is a scientific discovery environment, an interactive simulated virtual laboratory, for learning physics and mathematics. The purpose of this computer-assisted intervention is to improve middle and high school student interest, insight and scores in physics and mathematics. SAVL develops scientific and mathematical imagination in a visual, symbolic, and experimental simulation environment. It directly addresses the issues of scientific and technological competency by providing critical thinking training through integrated modules. This on-going research provides a virtual laboratory environment in which the student directs the building of the experiment rather than observing a packaged simulation. SAVL: * Engages the persistent interest of young minds in physics and math by visually linking simulation objects and events with mathematical relations. * Teaches integrated concepts by the hands-on exploration and focused visualization of classic physics experiments within software. * Systematically and uniformly assesses and scores students by their ability to answer their own questions within the context of a Master Question Network. We will demonstrate how the Master Question Network uses polymorphic interfaces and C# lambda expressions to manage simulation objects.
Impact of a Paper vs Virtual Simulated Patient Case on Student-Perceived Confidence and Engagement
Gallimore, Casey E.; Pitterle, Michael; Morrill, Josh
2016-01-01
Objective. To evaluate online case simulation vs a paper case on student confidence and engagement. Design. Students enrolled in a pharmacotherapy laboratory course completed a patient case scenario as a component of an osteoarthritis laboratory module. Two laboratory sections used a paper case (n=53); three sections used an online virtual case simulation (n=81). Student module performance was assessed through a submitted subjective objective assessment plan (SOAP) note. Students completed pre/post surveys to measure self-perceived confidence in providing medication management. The simulation group completed postmodule questions related to realism and engagement of the online virtual case simulation. Group assessments were performed using chi-square and Mann Whitney tests. Assessment. A significant increase in all 13 confidence items was seen in both student groups following completion of the laboratory module. The simulation group had an increased change of confidence compared to the paper group in assessing medication efficacy and documenting a thorough assessment. Comparing the online virtual simulation to a paper case, students agreed the learning experience increased interest, enjoyment, relevance, and realism. The simulation group performed better on the subjective SOAP note domain though no differences in total SOAP note scores was found between the two groups. Conclusion. Virtual case simulations result in increased student engagement and may lead to improved documentation performance in the subjective domain of SOAP notes. However, virtual patient cases may offer limited benefit over paper cases in improving overall student self-confidence to provide medication management. PMID:26941442
Impact of a Paper vs Virtual Simulated Patient Case on Student-Perceived Confidence and Engagement.
Barnett, Susanne G; Gallimore, Casey E; Pitterle, Michael; Morrill, Josh
2016-02-25
To evaluate online case simulation vs a paper case on student confidence and engagement. Students enrolled in a pharmacotherapy laboratory course completed a patient case scenario as a component of an osteoarthritis laboratory module. Two laboratory sections used a paper case (n=53); three sections used an online virtual case simulation (n=81). Student module performance was assessed through a submitted subjective objective assessment plan (SOAP) note. Students completed pre/post surveys to measure self-perceived confidence in providing medication management. The simulation group completed postmodule questions related to realism and engagement of the online virtual case simulation. Group assessments were performed using chi-square and Mann Whitney tests. A significant increase in all 13 confidence items was seen in both student groups following completion of the laboratory module. The simulation group had an increased change of confidence compared to the paper group in assessing medication efficacy and documenting a thorough assessment. Comparing the online virtual simulation to a paper case, students agreed the learning experience increased interest, enjoyment, relevance, and realism. The simulation group performed better on the subjective SOAP note domain though no differences in total SOAP note scores was found between the two groups. Virtual case simulations result in increased student engagement and may lead to improved documentation performance in the subjective domain of SOAP notes. However, virtual patient cases may offer limited benefit over paper cases in improving overall student self-confidence to provide medication management.
Dynamics of visual feedback in a laboratory simulation of a penalty kick.
Morya, Edgard; Ranvaud, Ronald; Pinheiro, Walter Machado
2003-02-01
Sport scientists have devoted relatively little attention to soccer penalty kicks, despite their decisive role in important competitions such as the World Cup. Two possible kicker strategies have been described: ignoring the goalkeeper action (open loop) or trying to react to the goalkeeper action (closed loop). We used a paradigm simulating a penalty kick in the laboratory to investigate the dynamics of the closed-loop strategy in these controlled conditions. The probability of correctly responding to the simulated goalkeeper motion as a function of time available followed a logistic curve. Kickers on average reached perfect performance only if the goalkeeper committed him or herself to one side about 400 ms before ball contact and showed chance performance if the goalkeeper motion occurred less than 150 ms before ball contact. Interestingly, coincidence judgement--another aspect of the laboratory responses--appeared to be affected for a much longer time (> 500 ms) than was needed to correctly determine laterality. The present study is meant as groundwork for experiments in more ecological conditions applicable to kickers and goalkeepers.
Laboratory investigation on super-Earths atmospheres
NASA Astrophysics Data System (ADS)
Erculiani, M. S.; Claudi, R. U.; Lessio, L.; Farisato, G.; Giro, E.; Cocola, L.; Billi, D.; D'alessandro, M.; Pace, E.; Schierano, D.; Benatti, S.; Bonavita, M.; Galletta, G.
2014-04-01
In the framework of Atmosphere in a Test Tube, at the Astronomical Observatory of Padova (INAF) we are going to perform experiments aimed to understand the possible modification of the atmosphere by photosynthetic biota present on the planet surface. This goal can be achieved simulating M star planetary environmental conditions. The bacteria that are being studied are Acaryochloris marina, Chroococcidiopsis spp. and Halomicronema hingdechloris. Tests will be performed with LISA or MINI-LISA ambient simulator in the laboratory of the Padova Astronomic Observatory. In this paper we describe the whole road map to follow in order to perform experiments and to obtain useful data to be compared with the real ones that will be obtained by the future space missions. Starting by a fiducial experiment we will modify either environmental and thermodynamical properties in order to simulate both real irradiation by an M star and gas mixture mimicing super earths atmospheres. These laboratory tests could be used as a guideline in order to understand whether chemical disequilibrium of O2, CO2 and CH4 could be ascribed to biotic life forms.
NASA Technical Reports Server (NTRS)
Steffes, P. G.
1986-01-01
The recognition of the need to make laboratory measurements of simulated planetary atmospheres over a range of temperatures and pressure which correspond to the altitudes probed by radio occultation experiments, and over a range of frequencies which correspond to both radio occultation experiments and radio astronomical observations, has led to the development of a facility at Georgia Tech which is capable of making such measurements. Construction was completed of the outer planets simulator and measurements were conducted of the microwave absorption and refraction from nitrogen under simulated Titan conditions. The results of these and previous laboratory measurements were applied to a wide range of microwave opacity measurements, in order to derive constituent densities and distributions in planetary atmospheres such as Venus.
Laboratory Studies of Methane and Its Relationship to Prebiotic Chemistry
NASA Astrophysics Data System (ADS)
Kobayashi, Kensei; Geppert, Wolf D.; Carrasco, Nathalie; Holm, Nils G.; Mousis, Olivier; Palumbo, Maria Elisabetta; Waite, J. Hunter; Watanabe, Naoki; Ziurys, Lucy M.
2017-08-01
To examine how prebiotic chemical evolution took place on Earth prior to the emergence of life, laboratory experiments have been conducted since the 1950s. Methane has been one of the key molecules in these investigations. In earlier studies, strongly reducing gas mixtures containing methane and ammonia were used to simulate possible reactions in the primitive atmosphere of Earth, producing amino acids and other organic compounds. Since Earth's early atmosphere is now considered to be less reducing, the contribution of extraterrestrial organics to chemical evolution has taken on an important role. Such organic molecules may have come from molecular clouds and regions of star formation that created protoplanetary disks, planets, asteroids, and comets. The interstellar origin of organics has been examined both experimentally and theoretically, including laboratory investigations that simulate interstellar molecular reactions. Endogenous and exogenous organics could also have been supplied to the primitive ocean, making submarine hydrothermal systems plausible sites of the generation of life. Experiments that simulate such hydrothermal systems where methane played an important role have consequently been conducted. Processes that occur in other Solar System bodies offer clues to the prebiotic chemistry of Earth. Titan and other icy bodies, where methane plays significant roles, are especially good targets. In the case of Titan, methane is both in the atmosphere and in liquidospheres that are composed of methane and other hydrocarbons, and these have been studied in simulation experiments. Here, we review the wide range of experimental work in which these various terrestrial and extraterrestrial environments have been modeled, and we examine the possible role of methane in chemical evolution.
Hati, Sanchita; Bhattacharyya, Sudeep
2016-01-01
A project-based biophysical chemistry laboratory course, which is offered to the biochemistry and molecular biology majors in their senior year, is described. In this course, the classroom study of the structure-function of biomolecules is integrated with the discovery-guided laboratory study of these molecules using computer modeling and simulations. In particular, modern computational tools are employed to elucidate the relationship between structure, dynamics, and function in proteins. Computer-based laboratory protocols that we introduced in three modules allow students to visualize the secondary, super-secondary, and tertiary structures of proteins, analyze non-covalent interactions in protein-ligand complexes, develop three-dimensional structural models (homology model) for new protein sequences and evaluate their structural qualities, and study proteins' intrinsic dynamics to understand their functions. In the fourth module, students are assigned to an authentic research problem, where they apply their laboratory skills (acquired in modules 1-3) to answer conceptual biophysical questions. Through this process, students gain in-depth understanding of protein dynamics-the missing link between structure and function. Additionally, the requirement of term papers sharpens students' writing and communication skills. Finally, these projects result in new findings that are communicated in peer-reviewed journals. © 2016 The International Union of Biochemistry and Molecular Biology.
Improved Pyrolysis Micro reactor Design via Computational Fluid Dynamics Simulations
2017-05-23
Dynamics Simulations Ghanshyam L. Vaghjiani Air Force Research Laboratory (AFMC) AFRL/RQRS 1 Ara Drive Edwards AFB, CA 93524-7013 Air Force...Aerospace Systems Directorate Air Force Research Laboratory AFRL/RQRS 1 Ara Road Edwards AFB, CA 93524 *Email: ghanshyam.vaghjiani@us.af.mil IMPROVED...PYROLYSIS MICRO-REACTOR DESIGN VIA COMPUTATIONAL FLUID DYNAMICS SIMULATIONS Ghanshyam L. Vaghjiani* DISTRIBUTION A: Approved for public release
Muon simulation codes MUSIC and MUSUN for underground physics
NASA Astrophysics Data System (ADS)
Kudryavtsev, V. A.
2009-03-01
The paper describes two Monte Carlo codes dedicated to muon simulations: MUSIC (MUon SImulation Code) and MUSUN (MUon Simulations UNderground). MUSIC is a package for muon transport through matter. It is particularly useful for propagating muons through large thickness of rock or water, for instance from the surface down to underground/underwater laboratory. MUSUN is designed to use the results of muon transport through rock/water to generate muons in or around underground laboratory taking into account their energy spectrum and angular distribution.
Additional confirmation of the validity of laboratory simulation of cloud radiances
NASA Technical Reports Server (NTRS)
Davis, J. M.; Cox, S. K.
1986-01-01
The results of a laboratory experiment are presented that provide additional verification of the methodology adopted for simulation of the radiances reflected from fields of optically thick clouds using the Cloud Field Optical Simulator (CFOS) at Colorado State University. The comparison of these data with their theoretically derived counterparts indicates that the crucial mechanism of cloud-to-cloud radiance field interaction is accurately simulated in the CFOS experiments and adds confidence to the manner in which the optical depth is scaled.
NASA Technical Reports Server (NTRS)
Roman, Juan A.; Stitt, George F.; Roman, Felix R.
1997-01-01
This paper will provide a general overview of the molecular contamination philosophy of the Space Simulation Test Engineering Section and how the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) space simulation laboratory controls and maintains the cleanliness of all its facilities, thereby, minimizing down time between tests. It will also briefly cover the proper selection and safety precautions needed when using some chemical solvents for wiping, washing, or spraying thermal shrouds when molecular contaminants increase to unacceptable background levels.
Rosebraugh, Matthew R; Widness, John A; Nalbant, Demet; Cress, Gretchen; Veng-Pedersen, Peter
2014-02-01
Preterm very-low-birth-weight (VLBW) infants weighing <1.5 kg at birth develop anemia, often requiring multiple red blood cell transfusions (RBCTx). Because laboratory blood loss is a primary cause of anemia leading to RBCTx in VLBW infants, our purpose was to simulate the extent to which RBCTx can be reduced or eliminated by reducing laboratory blood loss in combination with pharmacodynamically optimized erythropoietin (Epo) treatment. Twenty-six VLBW ventilated infants receiving RBCTx were studied during the first month of life. RBCTx simulations were based on previously published RBCTx criteria and data-driven Epo pharmacodynamic optimization of literature-derived RBC life span and blood volume data corrected for phlebotomy loss. Simulated pharmacodynamic optimization of Epo administration and reduction in phlebotomy by ≥ 55% predicted a complete elimination of RBCTx in 1.0-1.5 kg infants. In infants <1.0 kg with 100% reduction in simulated phlebotomy and optimized Epo administration, a 45% reduction in RBCTx was predicted. The mean blood volume drawn from all infants was 63 ml/kg: 33% required for analysis and 67% discarded. When reduced laboratory blood loss and optimized Epo treatment are combined, marked reductions in RBCTx in ventilated VLBW infants were predicted, particularly among those with birth weights >1.0 kg.
Waggoner, Lauren B; Grant, Devon A; Van Dongen, Hans P A; Belenky, Gregory; Vila, Bryan
2012-11-01
This study assessed the utility of a combined field and laboratory research design for measuring the impact of consecutive night shift work on the sleepiness, vigilance, and driving performance of police patrol officers. For police patrol officers working their normal night shift duty cycles, simulated driving performance and psychomotor vigilance were measured in a laboratory on two separate occasions: in the morning after the last of five consecutive 10.7-h night shifts, and at the same time in the morning after three consecutive days off duty. Order of participation in conditions was randomized among subjects. Subjects experienced manipulation of sleep schedules due to working night shifts in a real operational environment, but performance testing was conducted under controlled laboratory conditions. N = 29 active-duty police patrol officers (27 male, 2 female; age 37.1 ± 6.3 years) working night shift schedules participated in this study. Simulated driving performance, psychomotor vigilance, and subjective sleepiness were significantly degraded following 5 consecutive night shifts as compared to 3 consecutive days off duty, indicating that active-duty police officers are susceptible to performance degradation as a consequence of working nights. This combined field and laboratory research design succeeded in bridging the gap between the realism of the operational environment and the control of laboratory performance testing, demonstrating that this is a useful approach for addressing the relationship between shift work induced fatigue and critical operational task performance.
Xiangyang Zhou; Shankar Mahalingam; David Weise
2007-01-01
This paper presents a combined study of laboratory scale fire spread experiments and a three-dimensional large eddy simulation (LES) to analyze the effect of terrain slope on marginal burning behavior in live chaparral shrub fuel beds. Line fire was initiated in single species fuel beds of four common chaparral plants under various fuel bed configurations and ambient...
Simulations of Bubble Motion in an Oscillating Liquid
NASA Astrophysics Data System (ADS)
Kraynik, A. M.; Romero, L. A.; Torczynski, J. R.
2010-11-01
Finite-element simulations are used to investigate the motion of a gas bubble in a liquid undergoing vertical vibration. The effect of bubble compressibility is studied by comparing "compressible" bubbles that obey the ideal gas law with "incompressible" bubbles that are taken to have constant volume. Compressible bubbles exhibit a net downward motion away from the free surface that does not exist for incompressible bubbles. Net (rectified) velocities are extracted from the simulations and compared with theoretical predictions. The dependence of the rectified velocity on ambient gas pressure, bubble diameter, and bubble depth are in agreement with the theory. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.
Semi-Automated Processing of Trajectory Simulator Output Files for Model Evaluation
2018-01-01
ARL-TR-8284 ● JAN 2018 US Army Research Laboratory Semi-Automated Processing of Trajectory Simulator Output Files for Model......Do not return it to the originator. ARL-TR-8284 ● JAN 2018 US Army Research Laboratory Semi-Automated Processing of Trajectory
PRACTICAL SIMULATION OF COMPOSTING IN THE LABORATORY
A closed incubation system was developed for laboratory simulation of composting conditions at the interior of a large compost pile. A conductive heat flux control system (CHFC) was used to adjust the temperature of the internal wall to that of the compost center and compensate f...
Modelling runoff on ceramic tile roofs using the kinematic wave equations
NASA Astrophysics Data System (ADS)
Silveira, Alexandre; Abrantes, João; de Lima, João; Lira, Lincoln
2016-04-01
Rainwater harvesting is a water saving alternative strategy that presents many advantages and can provide solutions to address major water resources problems, such as fresh water scarcity, urban stream degradation and flooding. In recent years, these problems have become global challenges, due to climatic change, population growth and increasing urbanisation. Generally, roofs are the first to come into contact with rainwater; thus, they are the best candidates for rainwater harvesting. In this context, the correct evaluation of roof runoff quantity and quality is essential to effectively design rainwater harvesting systems. Despite this, many studies usually focus on the qualitative aspects in detriment of the quantitative aspects. Laboratory studies using rainfall simulators have been widely used to investigate rainfall-runoff processes. These studies enabled a detailed exploration and systematic replication of a large range of hydrologic conditions, such as rainfall spatial and temporal characteristics, providing for a fast way to obtain precise and consistent data that can be used to calibrate and validate numerical models. This study aims to evaluate the performance of a kinematic wave based numerical model in simulating runoff on sloping roofs, by comparing the numerical results with the ones obtained from laboratory rainfall simulations on a real-scale ceramic tile roof (Lusa tiles). For all studied slopes, simulated discharge hydrographs had a good adjust to observed ones. Coefficient of determination and Nash-Sutcliffe efficiency values were close to 1.0. Particularly, peak discharges, times to peak and peak durations were very well simulated.
Suslu, Husnu
2012-01-01
Laboratory training models are essential for developing and refining treatment skills before the clinical application of surgical and invasive procedures. A simple simulation model is needed for young trainees to learn how to handle instruments, and to perform safe lumbar transforaminal epidural injections. Our aim is to present a model of a fresh cadaveric sheep lumbar spine that simulates the lumbar transforaminal epidural injection. The material consists of a 2-year-old fresh cadaveric sheep spine. A 4-step approach was designed for lumbar transforaminal epidural injection under C-arm scopy. For the lumbar transforaminal epidural injection, the fluoroscope was adjusted to get a proper oblique view while the material was stabilized in a prone position. The procedure then begin, using the C-arm guidance scopy. The model simulates well the steps of standard lumbar transforaminal epidural injections in the human spine. The cadaveric sheep spine represents a good method for training and it simulates fluoroscopic lumbar transforaminal epidural steroid injection procedures performed in the human spine.
Gawande, Nitin A; Reinhart, Debra R; Yeh, Gour-Tsyh
2010-02-01
Biodegradation process modeling of municipal solid waste (MSW) bioreactor landfills requires the knowledge of various process reactions and corresponding kinetic parameters. Mechanistic models available to date are able to simulate biodegradation processes with the help of pre-defined species and reactions. Some of these models consider the effect of critical parameters such as moisture content, pH, and temperature. Biomass concentration is a vital parameter for any biomass growth model and often not compared with field and laboratory results. A more complex biodegradation model includes a large number of chemical and microbiological species. Increasing the number of species and user defined process reactions in the simulation requires a robust numerical tool. A generalized microbiological and chemical model, BIOKEMOD-3P, was developed to simulate biodegradation processes in three-phases (Gawande et al. 2009). This paper presents the application of this model to simulate laboratory-scale MSW bioreactors under anaerobic conditions. BIOKEMOD-3P was able to closely simulate the experimental data. The results from this study may help in application of this model to full-scale landfill operation.
Enhanced Verification Test Suite for Physics Simulation Codes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kamm, J R; Brock, J S; Brandon, S T
2008-10-10
This document discusses problems with which to augment, in quantity and in quality, the existing tri-laboratory suite of verification problems used by Los Alamos National Laboratory (LANL), Lawrence Livermore National Laboratory (LLNL), and Sandia National Laboratories (SNL). The purpose of verification analysis is demonstrate whether the numerical results of the discretization algorithms in physics and engineering simulation codes provide correct solutions of the corresponding continuum equations. The key points of this document are: (1) Verification deals with mathematical correctness of the numerical algorithms in a code, while validation deals with physical correctness of a simulation in a regime of interest.more » This document is about verification. (2) The current seven-problem Tri-Laboratory Verification Test Suite, which has been used for approximately five years at the DOE WP laboratories, is limited. (3) Both the methodology for and technology used in verification analysis have evolved and been improved since the original test suite was proposed. (4) The proposed test problems are in three basic areas: (a) Hydrodynamics; (b) Transport processes; and (c) Dynamic strength-of-materials. (5) For several of the proposed problems we provide a 'strong sense verification benchmark', consisting of (i) a clear mathematical statement of the problem with sufficient information to run a computer simulation, (ii) an explanation of how the code result and benchmark solution are to be evaluated, and (iii) a description of the acceptance criterion for simulation code results. (6) It is proposed that the set of verification test problems with which any particular code be evaluated include some of the problems described in this document. Analysis of the proposed verification test problems constitutes part of a necessary--but not sufficient--step that builds confidence in physics and engineering simulation codes. More complicated test cases, including physics models of greater sophistication or other physics regimes (e.g., energetic material response, magneto-hydrodynamics), would represent a scientifically desirable complement to the fundamental test cases discussed in this report. The authors believe that this document can be used to enhance the verification analyses undertaken at the DOE WP Laboratories and, thus, to improve the quality, credibility, and usefulness of the simulation codes that are analyzed with these problems.« less
(U) Status of Trinity and Crossroads Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Archer, Billy Joe; Lujan, James Westley; Hemmert, K. S.
2017-01-10
(U) This paper provides a general overview of current and future plans for the Advanced Simulation and Computing (ASC) Advanced Technology (AT) systems fielded by the New Mexico Alliance for Computing at Extreme Scale (ACES), a collaboration between Los Alamos Laboratory and Sandia National Laboratories. Additionally, this paper touches on research of technology beyond traditional CMOS. The status of Trinity, ASCs first AT system, and Crossroads, anticipated to succeed Trinity as the third AT system in 2020 will be presented, along with initial performance studies of the Intel Knights Landing Xeon Phi processors, introduced on Trinity. The challenges and opportunitiesmore » for our production simulation codes on AT systems will also be discussed. Trinity and Crossroads are a joint procurement by ACES and Lawrence Berkeley Laboratory as part of the Alliance for application Performance at EXtreme scale (APEX) http://apex.lanl.gov.« less
Perceptual Performance Impact of GPU-Based WARP and Anti-Aliasing for Image Generators
2016-06-29
with the Air Force Research Laboratory (AFRL) and NASA AMES, constructed the Operational Based Vision Assessment (OBVA) simulator. This 15-channel, 150...ABSTRACT In 2012 the U.S. Air Force School of Aerospace Medicine, in partnership with the Air Force Research Laboratory (AFRL) and NASA AMES...with the Air Force Research Laboratory (AFRL) and NASA AMES, constructed the Operational Based Vision Assessment (OBVA) simulator to evaluate the
NASA Astrophysics Data System (ADS)
Petersen, D.; Bailey, M.; Hallett, J.; Beasley, W.
2007-12-01
The initiation of lightning remains an open question, due in large part to a deficit of in-situ observational evidence. Recent theoretical descriptions of lightning initiation have focused on runaway breakdown and related secondary processes, but have not convincingly explained the details of onset of the embryonic lightning leader channel. Among possible mechanisms contributing to the initial leader formation are positive streamer discharges from ice hydrometeors, themselves once favored as the primary explanation of lightning initiation. We present preliminary results from a new laboratory study of positive streamer discharges on simulated ice hydrometeors. Emphasis is given to precisely defining the minimum electric field strength required for onset of positive streamer generation, with variables of interest being ice crystal size, habit and environmental temperature.
Note: Measurement system for the radiative forcing of greenhouse gases in a laboratory scale.
Kawamura, Yoshiyuki
2016-01-01
The radiative forcing of the greenhouse gases has been studied being based on computational simulations or the observation of the real atmosphere meteorologically. In order to know the greenhouse effect more deeply and to study it from various viewpoints, the study on it in a laboratory scale is important. We have developed a direct measurement system for the infrared back radiation from the carbon dioxide (CO2) gas. The system configuration is similar with that of the practical earth-atmosphere-space system. Using this system, the back radiation from the CO2 gas was directly measured in a laboratory scale, which roughly coincides with meteorologically predicted value.
Simulation of Fatigue Crack Initiation at Corrosion Pits With EDM Notches
NASA Technical Reports Server (NTRS)
Smith, Stephen W.; Newman, John A.; Piascik, Robert S.
2003-01-01
Uniaxial fatigue tests were conducted to compare the fatigue life of laboratory produced corrosion pits, similar to those observed in the shuttle main landing gear wheel bolt-hole, and an electro-discharged-machined (EDM) flaw. EDM Jaws are used to simulate corrosion pits during shuttle wheel (dynamometer) testing. The aluminum alloy, (AA 7050) laboratory fatigue tests were conducted to simulate the local stress level contained in the wheel bolt-hole. Under this high local stress condition, the EDM notch produced a fatigue life similar to test specimens containing corrosion pits of similar size. Based on the laboratory fatigue test results, the EDM Jaw (semi-circular disc shaped) produces a local stress state similar to corrosion pits and can be used to simulate a corrosion pit during the shuttle wheel dynamometer tests.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Im, Piljae; Cho, Heejin; Kim, Dongsu
2016-08-01
This report provides second-year project simulation results for the multi-year project titled “Evaluation of Variable Refrigeration Flow (VRF) system on Oak Ridge National Laboratory (ORNL)’s Flexible Research Platform (FRP).”
Laboratory simulation of rocket-borne D-region blunt probe flows
NASA Technical Reports Server (NTRS)
Kaplan, L. B.
1977-01-01
The flow of weakly ionized plasmas that is similar to the flow that occurs over rocket-borne blunt probes as they pass through the lower ionosphere has been simulated in a scaled laboratory environment, and electron collection D region blunt probe theories have been evaluated.
A-SIDE: Video Simulation of Teen Alcohol and Marijuana Use Contexts
Anderson, Kristen G; Brackenbury, Lauren; Quackenbush, Mathias; Buras, Morgan; Brown, Sandra A; Price, Joseph
2014-01-01
Objective: This investigation examined the concurrent validity of a new video simulation assessing adolescent alcohol and marijuana decision making in peer contexts (A-SIDE). Method: One hundred eleven youth (60% female; age 14–19 years; 80% White, 12.6% Latino; 24% recruited from treatment centers) completed the A-SIDE simulation, self-report measures of alcohol and marijuana use and disorder symptoms, and measures of alcohol (i.e., drinking motives and expectancies) and marijuana (i.e., expectancies) cognitions in the laboratory. Results: Study findings support concurrent associations between behavioral willingness to use alcohol and marijuana on the simulation and current use variables as well as on drinking motives and marijuana expectancies. Relations with use variables were found even when sample characteristics were controlled. Interestingly, willingness to accept nonalcoholic beverages (e.g., soda) and food offers in the simulation were inversely related to recent alcohol and marijuana use behavior. Conclusions: These findings are consistent with prior work using laboratory simulations with college students and provide preliminary validity evidence for this procedure. Future work is needed to examine the predictive utility of the A-SIDE with larger and more diverse samples of youth. PMID:25343652
ERIC Educational Resources Information Center
Booth, Paula; Henderson-Begg, Stephanie
2011-01-01
Invited as a paper from E-Learn 2009 This study compared two programmes developed as a learning tool for students to practise basic laboratory procedures. One was a Flash simulation programme, the other a Second Life virtual reality programme. A cohort of 93 bioscience students participated in the between trial. A control group was used to…
Okunribido, Olanrewaju O
2013-01-01
This article is a report of a study of the effect of the seat cushion on risk of falling from a wheelchair. Two laboratory studies and simulated assistant propelled wheelchair transfers were conducted with four healthy female participants. For the laboratory studies there were three independent variables: trunk posture (upright/flexed forward), seat cushion (flat polyurethane/propad low profile), and feet condition (dangling/supported), and two dependent variables: occupied wheelchair (wheelchair) center of gravity (CG), and stability. For the simulated transfers there was one independent variable: seat cushion (flat polyurethane/propad low profile), and one dependent variable: perception of safety (risk of falling). Results showed that the wheelchair CG was closer to the front wheels, and stability lower for the propad low profile cushion compared to the polyurethane cushion, when the participants sat with their feet dangling. During the simulated transfers, sitting on the propad low profile cushion caused participants to feel more apprehensive (anxious or uneasy) compared to sitting on the polyurethane cushion. The findings can contribute to the assessment of risk and care planning of non-ambulatory wheelchair users.
Research highlights of the global modeling and simulation branch for 1986-1987
NASA Technical Reports Server (NTRS)
Baker, Wayman (Editor); Susskind, Joel (Editor); Pfaendtner, James (Editor); Randall, David (Editor); Atlas, Robert (Editor)
1988-01-01
This document provides a summary of the research conducted in the Global Modeling and Simulation Branch and highlights the most significant accomplishments in 1986 to 1987. The Branch has been the focal point for global weather and climate prediction research in the Laboratory for Atmospheres through the retrieval and use of satellite data, the development of global models and data assimilation techniques, the simulation of future observing systems, and the performance of atmospheric diagnostic studies.
Research Triangle Park, NC Laboratory at a Glance
Among many other things, EPA's Research Triangle Park scientists simulate many different types of air pollution under varying meteorological conditions and study the health effects of air pollution mixtures.
ERIC Educational Resources Information Center
Richardson, Jeffrey J.; Adamo-Villani, Nicoletta
2010-01-01
Laboratory instruction is a major component of the engineering and technology undergraduate curricula. Traditional laboratory instruction is hampered by several factors including limited access to resources by students and high laboratory maintenance cost. A photorealistic 3D computer-simulated laboratory for undergraduate instruction in…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Finsterle, S.; Moridis, G.J.; Pruess, K.
1994-01-01
The emplacement of liquids under controlled viscosity conditions is investigated by means of numerical simulations. Design calculations are performed for a laboratory experiment on a decimeter scale, and a field experiment on a meter scale. The purpose of the laboratory experiment is to study the behavior of multiple gout plumes when injected in a porous medium. The calculations for the field trial aim at designing a grout injection test from a vertical well in order to create a grout plume of a significant extent in the subsurface.
Effects of solid barriers on dispersion of roadway emissions
Several studies have found that exposure to traffic-generated air pollution is associated with several adverse health effects. Field studies, laboratory experiments, and numerical simulations indicate that roadside barriers represent a practical method of mitigating the impact of...
Tawalbeh, Loai I
2017-08-01
Simulation is an effective teaching strategy. However, no study in Jordan has examined the effect of simulation on the confidence of university nursing students in applying heart and lung physical examination skills. The current study aimed to test the effect of simulation on the confidence of university nursing students in applying heart and lung physical examination skills. A randomized controlled trial design was applied. The researcher introduced the simulation scenario regarding cardiopulmonary examination skills. This scenario included a 1-hour PowerPoint presentation and video for the experimental group (n= 35) and a PowerPoint presentation and a video showing a traditional demonstration in the laboratory for the control group (n = 34). Confidence in applying cardiopulmonary physical examination skills was measured for both groups at baseline and at 1 day and 3 months posttest. A paired t test showed that confidence was significantly higher in the posttest than in the pretest for both groups. An independent t test showed a statistically significant difference (t(67) = -42.95, p < .001) between the two groups in terms of the difference between the first posttest and second posttest scores (t(67) = -43.36, p < .001) for confidence in applying physical examination skills. Both simulation and traditional training in the laboratory significantly improved the confidence of participants in applying cardiopulmonary assessment skills. However, the simulation training had a more significant effect than usual training in enhancing the confidence of nursing students in applying physical examination skills.
Bootstrapping Methods Applied for Simulating Laboratory Works
ERIC Educational Resources Information Center
Prodan, Augustin; Campean, Remus
2005-01-01
Purpose: The aim of this work is to implement bootstrapping methods into software tools, based on Java. Design/methodology/approach: This paper presents a category of software e-tools aimed at simulating laboratory works and experiments. Findings: Both students and teaching staff use traditional statistical methods to infer the truth from sample…
ERIC Educational Resources Information Center
Grimes, William J.; Chambers, Linda; Kubo, Kenneth M.; Narro, Martha L.
1998-01-01
Describes a laboratory exercise that simulates the spread of an infectious agent among students in a classroom. Uses a modified Enzyme Linked ImmunoSorbent Assay (ELISA) to provide students with experience using an authentic diagnostic tool for detecting human infections. (DDR)
Validation of mathematical model for CZ process using small-scale laboratory crystal growth furnace
NASA Astrophysics Data System (ADS)
Bergfelds, Kristaps; Sabanskis, Andrejs; Virbulis, Janis
2018-05-01
The present material is focused on the modelling of small-scale laboratory NaCl-RbCl crystal growth furnace. First steps towards fully transient simulations are taken in the form of stationary simulations that deal with the optimization of material properties to match the model to experimental conditions. For this purpose, simulation software primarily used for the modelling of industrial-scale silicon crystal growth process was successfully applied. Finally, transient simulations of the crystal growth are presented, giving a sufficient agreement to experimental results.
A daylong clinical laboratory: from gaming to high-fidelity simulators.
Bantz, Diana; Dancer, Michelle Mattice; Hodson-Carlton, Kay; Van Hove, Sharon
2007-01-01
Meeting required objectives in the clinical setting can be difficult because of low exposure to critical events. This has been further compounded by an increase in the number of enrolling students without a reciprocal rise in the number of field-related clinical sites. As simulation gains popularity in nursing, exploration of its use and benefits to teach nursing-related concepts is desirable. The authors discuss a variety of teaching strategies ranging from the use of games to high-fidelity simulators that have been incorporated into an all-day clinical simulation campus laboratory.
Modelling and scale-up of chemical flooding
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pope, G.A.; Lake, L.W.; Sepehrnoori, K.
1990-03-01
The objective of this research is to develop, validate, and apply a comprehensive chemical flooding simulator for chemical recovery processes involving surfactants, polymers, and alkaline chemicals in various combinations. This integrated program includes components of laboratory experiments, physical property modelling, scale-up theory, and numerical analysis as necessary and integral components of the simulation activity. We have continued to develop, test, and apply our chemical flooding simulator (UTCHEM) to a wide variety of laboratory and reservoir problems involving tracers, polymers, polymer gels, surfactants, and alkaline agents. Part I is an update on the Application of Higher-Order Methods in Chemical Flooding Simulation.more » This update focuses on the comparison of grid orientation effects for four different numerical methods implemented in UTCHEM. Part II is on Simulation Design Studies and is a continuation of Saad's Big Muddy surfactant pilot simulation study reported last year. Part III reports on the Simulation of Gravity Effects under conditions similar to those of some of the oil reservoirs in the North Sea. Part IV is on Determining Oil Saturation from Interwell Tracers UTCHEM is used for large-scale interwell tracer tests. A systematic procedure for estimating oil saturation from interwell tracer data is developed and a specific example based on the actual field data provided by Sun E P Co. is given. Part V reports on the Application of Vectorization and Microtasking for Reservoir Simulation. Part VI reports on Alkaline Simulation. The alkaline/surfactant/polymer flood compositional simulator (UTCHEM) reported last year is further extended to include reactions involving chemical species containing magnesium, aluminium and silicon as constituent elements. Part VII reports on permeability and trapping of microemulsion.« less
Simulating Extraterrestrial Ices in the Laboratory
NASA Astrophysics Data System (ADS)
Berisford, D. F.; Carey, E. M.; Hand, K. P.; Choukroun, M.
2017-12-01
Several ongoing experiments at JPL attempt to simulate the ice environment for various regimes associated with icy moons. The Europa Penitent Ice Experiment (EPIX) simulates the surface environment of an icy moon, to investigate the physics of ice surface morphology growth. This experiment features half-meter-scale cryogenic ice samples, cryogenic radiative sink environment, vacuum conditions, and diurnal cycling solar simulation. The experiment also includes several smaller fixed-geometry vacuum chambers for ice simulation at Earth-like and intermediate temperature and vacuum conditions for development of surface morphology growth scaling relations. Additionally, an ice cutting facility built on a similar platform provides qualitative data on the mechanical behavior of cryogenic ice with impurities under vacuum, and allows testing of ice cutting/sampling tools relevant for landing spacecraft. A larger cutting facility is under construction at JPL, which will provide more quantitative data and allow full-scale sampling tool tests. Another facility, the JPL Ice Physics Laboratory, features icy analog simulant preparation abilities that range icy solar system objects such as Mars, Ceres and the icy satellites of Saturn and Jupiter. In addition, the Ice Physics Lab has unique facilities for Icy Analog Tidal Simulation and Rheological Studies of Cryogenic Icy Slurries, as well as equipment to perform thermal and mechanical properties testing on icy analog materials and their response to sinusoidal tidal stresses.
Identification of prelinguistic phonological categories.
Ramsdell, Heather L; Oller, D Kimbrough; Buder, Eugene H; Ethington, Corinna A; Chorna, Lesya
2012-12-01
The prelinguistic infant's babbling repertoire of syllables--the phonological categories that form the basis for early word learning--is noticed by caregivers who interact with infants around them. Prior research on babbling has not explored the caregiver's role in recognition of early vocal categories as foundations for word learning. In the present work, the authors begin to address this gap. The authors explored vocalizations produced by 8 infants at 3 ages (8, 10, and 12 months) in studies illustrating identification of phonological categories through caregiver report, laboratory procedures simulating the caregiver's natural mode of listening, and the more traditional laboratory approach (phonetic transcription). Caregivers reported small repertoires of syllables for their infants. Repertoires of similar size and phonetic content were discerned in the laboratory by judges who simulated the caregiver's natural mode of listening. However, phonetic transcription with repeated listening to infant recordings yielded repertoire sizes that vastly exceeded those reported by caregivers and naturalistic listeners. The results suggest that caregiver report and naturalistic listening by laboratory staff can provide a new way to explore key characteristics of early infant vocal categories, a way that may provide insight into later speech and language development.
Modeling and Simulation of Ballistic Penetration of Ceramic-Polymer-Metal Layered Systems
2016-01-01
ARL-RP-0562 ● JAN 2016 US Army Research Laboratory Modeling and Simulation of Ballistic Penetration of Ceramic-Polymer-Metal...manufacturer’s or trade names does not constitute an official endorsement or approval of the use thereof. Destroy this report when it is no longer needed...Do not return it to the originator. ARL-RP-0562 ● JAN 2016 US Army Research Laboratory Modeling and Simulation of Ballistic
Study on the decomposition of trace benzene over V2O5-WO3/TiO2-based catalysts in simulated flue gas
Commercial and laboratory-prepared V2O5–WO3/TiO2-based catalysts with different compositions were tested for catalytic decomposition of chlorobenzene (ClBz) in simulated flue gas. Resonance enhanced multiphoton ionization-time of flight mass spectrometry (REMPI-TOFMS) was employe...
Activity of earthworm in Latosol under simulated acid rain stress
Jia-En Zhang; Jiayu Yu; Ying Ouyang
2015-01-01
Acid rain is still an issue of environmental concerns. This study investigated the impacts of simulated acid rain (SAR) upon earthworm activity from the Latosol (acidic red soil). Laboratory experiment was performed by leaching the soil columns grown with earthworms (Eisenia fetida) at the SAR pH levels ranged from 2.0 to 6.5 over a 34-day period....
Kubota, Rie; Shibuya, Kiyoshi; Tanaka, Yoichi; Aoki, Manahito; Shiomi, Megumi; Ando, Wataru; Otori, Katsuya; Komiyama, Takako
2018-06-01
The Japanese pharmaceutical curriculum was extended from four to six years in 2006. Students now receive practical communication-skills training in their fourth year, before progressing to train in hospital and community pharmacies in their fifth year. Kitasato University School of Pharmacy, Tokyo, had established a program to meet these aims before the 2006 guidance. In the present study, we discuss and evaluate the features of this communication-skills training program. This study enrolled 242 fourth-year pharmacy students at Kitasato University. Students filled out a questionnaire survey after completing the laboratory element of their undergraduate education. As part of training, students were asked to obtain patient data from a model medical chart, before performing simulated patient interviews covering hospital admission and patient counseling. These simulations were repeated in a small group, and feedback was provided to students by both the simulated patient and the faculty after each presentation. It was found that students were able to develop their communication skills through this approach. Thus, an effective system of gradual and continuous training has been developed, which allows students to acquire clinical and practical communication skills.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pope, G.A.; Lake, L.W.; Sepehrnoori, K.
1988-11-01
The objective of this research is to develop, validate, and apply a comprehensive chemical flooding simulator for chemical recovery processes involving surfactants, polymers, and alkaline chemicals in various combinations. This integrated program includes components of laboratory experiments, physical property modelling, scale-up theory, and numerical analysis as necessary and integral components of the simulation activity. Developing, testing and applying flooding simulator (UTCHEM) to a wide variety of laboratory and reservoir problems involving tracers, polymers, polymer gels, surfactants, and alkaline agent has been continued. Improvements in both the physical-chemical and numerical aspects of UTCHEM have been made which enhance its versatility, accuracymore » and speed. Supporting experimental studies during the past year include relative permeability and trapping of microemulsion, tracer flow studies oil recovery in cores using alcohol free surfactant slugs, and microemulsion viscosity measurements. These have enabled model improvement simulator testing. Another code called PROPACK has also been developed which is used as a preprocessor for UTCHEM. Specifically, it is used to evaluate input to UTCHEM by computing and plotting key physical properties such as phase behavior interfacial tension.« less
NASA Astrophysics Data System (ADS)
Tomshaw, Stephen G.
Physics education research has shown that students bring alternate conceptions to the classroom which can be quite resistant to traditional instruction methods (Clement, 1982; Halloun & Hestenes, 1985; McDermott, 1991). Microcomputer-based laboratory (MBL) experiments that employ an active-engagement strategy have been shown to improve student conceptual understanding in high school and introductory university physics courses (Thornton & Sokoloff, 1998). These (MBL) experiments require a specialized computer interface, type-specific sensors (e.g. motion detectors, force probes, accelerometers), and specialized software in addition to the standard physics experimental apparatus. Tao and Gunstone (1997) have shown that computer simulations used in an active engagement environment can also lead to conceptual change. This study investigated 69 secondary physics students' use of computer simulations of MBL activities in place of the hands-on MBL laboratory activities. The average normalized gain
Simulation approach for optimization of ZnO/c-WSe{}_{2} heterojunction solar cells
NASA Astrophysics Data System (ADS)
Huang, Shihua; Li, Qiannan; Chi, Dan; Meng, Xiuqing; He, Lü
2017-04-01
Taking into account defect density in WSe{}2, interface recombination between ZnO and WSe{}2, we presented a simulation study of ZnO/crystalline WSe{}2 heterojunction (HJ) solar cell using wxAMPS simulation software. The optimal conversion efficiency 39.07% for n-ZnO/p-c-WSe{}2 HJ solar cell can be realized without considering the impact of defects. High defect density (> 1.0× {10}11 cm{}-2) in c-WSe{}2 and large trap cross-section (> 1.0 × 10{}-10 cm{}2) have serious impact on solar cell efficiency. A thin p-WSe{}2 layer is intentionally inserted between ZnO layer and c-WSe{}2 to investigate the effect of the interface recombination. The interface properties are very crucial to the performance of ZnO/c-WSe{}2HJ solar cell. The affinity of ZnO value range between 3.7-4.5 eV gives the best conversion efficiency. Project supported by the Natural Science Foundation of Zhejiang Province (No. LY17F040001), the Open Project Program of Surface Physics Laboratory (National Key Laboratory) of Fudan University (No. KF2015_02), the Open Project Program of National Laboratory for Infrared Physics, Chinese Academy of Sciences (No. M201503), the Zhejiang Provincial Science and Technology Key Innovation Team (No. 2011R50012), and the Zhejiang Provincial Key Laboratory (No. 2013E10022).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lundstrom, Blake; Chakraborty, Sudipta; Lauss, Georg
This paper presents a concise description of state-of-the-art real-time simulation-based testing methods and demonstrates how they can be used independently and/or in combination as an integrated development and validation approach for smart grid DERs and systems. A three-part case study demonstrating the application of this integrated approach at the different stages of development and validation of a system-integrated smart photovoltaic (PV) inverter is also presented. Laboratory testing results and perspectives from two international research laboratories are included in the case study.
A meta-analysis of outcomes from the use of computer-simulated experiments in science education
NASA Astrophysics Data System (ADS)
Lejeune, John Van
The purpose of this study was to synthesize the findings from existing research on the effects of computer simulated experiments on students in science education. Results from 40 reports were integrated by the process of meta-analysis to examine the effect of computer-simulated experiments and interactive videodisc simulations on student achievement and attitudes. Findings indicated significant positive differences in both low-level and high-level achievement of students who use computer-simulated experiments and interactive videodisc simulations as compared to students who used more traditional learning activities. No significant differences in retention, student attitudes toward the subject, or toward the educational method were found. Based on the findings of this study, computer-simulated experiments and interactive videodisc simulations should be used to enhance students' learning in science, especially in cases where the use of traditional laboratory activities are expensive, dangerous, or impractical.
Nichols, Peter W B; White, Richard; Lucke, Terry
2015-04-01
Previous studies have attempted to quantify the clogging processes of Permeable Interlocking Concrete Pavers (PICPs) using accelerated testing methods. However, the results have been variable. This study investigated the effects that three different sediment types (natural and silica), and different simulated rainfall intensities, and testing durations had on the observed clogging processes (and measured surface infiltration rates) of laboratory-based, accelerated PICP testing studies. Results showed that accelerated simulated laboratory testing results are highly dependent on the type, and size of sediment used in the experiments. For example, when using real stormwater sediment up to 1.18 mm in size, the results showed that neither testing duration, nor stormwater application rate had any significant effect on PICP clogging. However, the study clearly showed that shorter testing durations generally increased clogging and reduced the surface infiltration rates of the models when artificial silica sediment was used. Longer testing durations also generally increased clogging of the models when using fine sediment (<300 μm). Results from this study will help researchers and designers better anticipate when and why PICPs are susceptible to clogging, reduce maintenance and extend the useful life of these increasingly common stormwater best management practices. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Tzeferacos, P.; Rigby, A.; Bott, A.; Bell, A. R.; Bingham, R.; Casner, A.; Cattaneo, F.; Churazov, E. M.; Emig, J.; Flocke, N.; Fiuza, F.; Forest, C. B.; Foster, J.; Graziani, C.; Katz, J.; Koenig, M.; Li, C.-K.; Meinecke, J.; Petrasso, R.; Park, H.-S.; Remington, B. A.; Ross, J. S.; Ryu, D.; Ryutov, D.; Weide, K.; White, T. G.; Reville, B.; Miniati, F.; Schekochihin, A. A.; Froula, D. H.; Gregori, G.; Lamb, D. Q.
2017-04-01
The universe is permeated by magnetic fields, with strengths ranging from a femtogauss in the voids between the filaments of galaxy clusters to several teragauss in black holes and neutron stars. The standard model behind cosmological magnetic fields is the nonlinear amplification of seed fields via turbulent dynamo to the values observed. We have conceived experiments that aim to demonstrate and study the turbulent dynamo mechanism in the laboratory. Here, we describe the design of these experiments through simulation campaigns using FLASH, a highly capable radiation magnetohydrodynamics code that we have developed, and large-scale three-dimensional simulations on the Mira supercomputer at the Argonne National Laboratory. The simulation results indicate that the experimental platform may be capable of reaching a turbulent plasma state and determining the dynamo amplification. We validate and compare our numerical results with a small subset of experimental data using synthetic diagnostics.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lefrancois, A.; Hare, D.; L'Eplattenier, P.
2006-02-13
Isentropic compression experiments and numerical simulations on LX-04 (HMX / Viton 85/15) were performed respectively at Z accelerator facility from Sandia National Laboratory and at Lawrence Livermore National Laboratory in order to study the isentrope and associated Hugoniot of this HE. 2D and 3D configurations have been calculated here to test the new beta version of the electromagnetism package coupled with the dynamics in Ls-Dyna and compared with the ICE Z shot 1067 on LX 04. The electromagnetism module is being developed in the general-purpose explicit and implicit finite element program LS-DYNA{reg_sign} in order to perform coupled mechanical/thermal/electromagnetism simulations. Themore » Maxwell equations are solved using a Finite Element Method (FEM) for the solid conductors coupled with a Boundary Element Method (BEM) for the surrounding air (or vacuum). More details can be read in the references.« less
Laboratory Studies of Methane and Its Relationship to Prebiotic Chemistry.
Kobayashi, Kensei; Geppert, Wolf D; Carrasco, Nathalie; Holm, Nils G; Mousis, Olivier; Palumbo, Maria Elisabetta; Waite, J Hunter; Watanabe, Naoki; Ziurys, Lucy M
2017-08-01
To examine how prebiotic chemical evolution took place on Earth prior to the emergence of life, laboratory experiments have been conducted since the 1950s. Methane has been one of the key molecules in these investigations. In earlier studies, strongly reducing gas mixtures containing methane and ammonia were used to simulate possible reactions in the primitive atmosphere of Earth, producing amino acids and other organic compounds. Since Earth's early atmosphere is now considered to be less reducing, the contribution of extraterrestrial organics to chemical evolution has taken on an important role. Such organic molecules may have come from molecular clouds and regions of star formation that created protoplanetary disks, planets, asteroids, and comets. The interstellar origin of organics has been examined both experimentally and theoretically, including laboratory investigations that simulate interstellar molecular reactions. Endogenous and exogenous organics could also have been supplied to the primitive ocean, making submarine hydrothermal systems plausible sites of the generation of life. Experiments that simulate such hydrothermal systems where methane played an important role have consequently been conducted. Processes that occur in other Solar System bodies offer clues to the prebiotic chemistry of Earth. Titan and other icy bodies, where methane plays significant roles, are especially good targets. In the case of Titan, methane is both in the atmosphere and in liquidospheres that are composed of methane and other hydrocarbons, and these have been studied in simulation experiments. Here, we review the wide range of experimental work in which these various terrestrial and extraterrestrial environments have been modeled, and we examine the possible role of methane in chemical evolution. Key Words: Methane-Interstellar environments-Submarine hydrothermal systems-Titan-Origin of life. Astrobiology 17, 786-812.
Tracing footprints of environmental events in tree ring chemistry using neutron activation analysis
NASA Astrophysics Data System (ADS)
Sahin, Dagistan
The aim of this study is to identify environmental effects on tree-ring chemistry. It is known that industrial pollution, volcanic eruptions, dust storms, acid rain and similar events can cause substantial changes in soil chemistry. Establishing whether a particular group of trees is sensitive to these changes in soil environment and registers them in the elemental chemistry of contemporary growth rings is the over-riding goal of any Dendrochemistry research. In this study, elemental concentrations were measured in tree-ring samples of absolutely dated eleven modern forest trees, grown in the Mediterranean region, Turkey, collected and dated by the Malcolm and Carolyn Wiener Laboratory for Aegean and Near Eastern Dendrochronology laboratory at Cornell University. Correlations between measured elemental concentrations in the tree-ring samples were analyzed using statistical tests to answer two questions. Does the current concentration of a particular element depend on any other element within the tree? And, are there any elements showing correlated abnormal concentration changes across the majority of the trees? Based on the detailed analysis results, the low mobility of sodium and bromine, positive correlations between calcium, zinc and manganese, positive correlations between trace elements lanthanum, samarium, antimony, and gold within tree-rings were recognized. Moreover, zinc, lanthanum, samarium and bromine showed strong, positive correlations among the trees and were identified as possible environmental signature elements. New Dendrochemistry information found in this study would be also useful in explaining tree physiology and elemental chemistry in Pinus nigra species grown in Turkey. Elemental concentrations in tree-ring samples were measured using Neutron Activation Analysis (NAA) at the Pennsylvania State University Radiation Science and Engineering Center (RSEC). Through this study, advanced methodologies for methodological, computational and experimental NAA were developed to ensure an acceptable accuracy and certainty in the elemental concentration measurements in tree-ring samples. Two independent analysis methods of NAA were used; the well known k-zero method and a novel method developed in this study, called the Multi-isotope Iterative Westcott (MIW) method. The MIW method uses reaction rate probabilities for a group of isotopes, which can be calculated by a neutronic simulation or measured by experimentation, and determines the representative values for the neutron flux and neutron flux characterization parameters based on Westcott convention. Elemental concentration calculations for standard reference material and tree-ring samples were then performed using the MIW and k-zero analysis methods of the NAA and the results were cross verified. In the computational part of this study, a detailed burnup coupled neutronic simulation was developed to analyze real-time neutronic changes in a TRIGA Mark III reactor core, in this study, the Penn State Breazeale Reactor (PSBR) core. To the best of the author`s knowledge, this is the first burnup coupled neutronic simulation with realistic time steps and full fuel temperature profile for a TRIGA reactor using Monte Carlo Utility for Reactor Evolutions (MURE) code and Monte Carlo Neutral-Particle Code (MCNP) coupling. High fidelity and flexibility in the simulation was aimed to replicate the real core operation through the day. This approach resulted in an enhanced accuracy in neutronic representation of the PSBR core with respect to previous neutronic simulation models for the PSBR core. An important contribution was made in the NAA experimentation practices employed in Dendrochemistry studies at the RSEC. Automated laboratory control and analysis software for NAA measurements in the RSEC Radionuclide Applications Laboratory was developed. Detailed laboratory procedures were written in this study comprising preparation, handling and measurements of tree-ring samples in the Radionuclide Applications Laboratory.
INL and NREL Demonstrate Power Grid Simulation at a Distance | News | NREL
RTDSs can form a virtual laboratory that allows multiple laboratories to cooperate on energy integration Laboratory (NREL) and Idaho National Laboratory (INL) have successfully demonstrated the capability to within the DOE national laboratory complex. The two national laboratories were able to connect their
Computational Electromagnetics (CEM) Laboratory: Simulation Planning Guide
NASA Technical Reports Server (NTRS)
Khayat, Michael A.
2011-01-01
The simulation process, milestones and inputs are unknowns to first-time users of the CEM Laboratory. The Simulation Planning Guide aids in establishing expectations for both NASA and non-NASA facility customers. The potential audience for this guide includes both internal and commercial spaceflight hardware/software developers. It is intended to assist their engineering personnel in simulation planning and execution. Material covered includes a roadmap of the simulation process, roles and responsibilities of facility and user, major milestones, facility capabilities, and inputs required by the facility. Samples of deliverables, facility interfaces, and inputs necessary to define scope, cost, and schedule are included as an appendix to the guide.
Application of lab derived kinetic biodegradation parameters at the field scale
NASA Astrophysics Data System (ADS)
Schirmer, M.; Barker, J. F.; Butler, B. J.; Frind, E. O.
2003-04-01
Estimating the intrinsic remediation potential of an aquifer typically requires the accurate assessment of the biodegradation kinetics, the level of available electron acceptors and the flow field. Zero- and first-order degradation rates derived at the laboratory scale generally overpredict the rate of biodegradation when applied to the field scale, because limited electron acceptor availability and microbial growth are typically not considered. On the other hand, field estimated zero- and first-order rates are often not suitable to forecast plume development because they may be an oversimplification of the processes at the field scale and ignore several key processes, phenomena and characteristics of the aquifer. This study uses the numerical model BIO3D to link the laboratory and field scale by applying laboratory derived Monod kinetic degradation parameters to simulate a dissolved gasoline field experiment at Canadian Forces Base (CFB) Borden. All additional input parameters were derived from laboratory and field measurements or taken from the literature. The simulated results match the experimental results reasonably well without having to calibrate the model. An extensive sensitivity analysis was performed to estimate the influence of the most uncertain input parameters and to define the key controlling factors at the field scale. It is shown that the most uncertain input parameters have only a minor influence on the simulation results. Furthermore it is shown that the flow field, the amount of electron acceptor (oxygen) available and the Monod kinetic parameters have a significant influence on the simulated results. Under the field conditions modelled and the assumptions made for the simulations, it can be concluded that laboratory derived Monod kinetic parameters can adequately describe field scale degradation processes, if all controlling factors are incorporated in the field scale modelling that are not necessarily observed at the lab scale. In this way, there are no scale relationships to be found that link the laboratory and the field scale, accurately incorporating the additional processes, phenomena and characteristics, such as a) advective and dispersive transport of one or more contaminants, b) advective and dispersive transport and availability of electron acceptors, c) mass transfer limitations and d) spatial heterogeneities, at the larger scale and applying well defined lab scale parameters should accurately describe field scale processes.
NASA Technical Reports Server (NTRS)
Wolegemuth, D. J.; Grills, G. S.
1984-01-01
The effects of weightlessness on three aspects of mammalian reproduction: oocyte development, fertilization, and early embryogenesis was studied. Zero-gravity conditions within the laboratory by construction of a clinostat designed to support in vitro tissue culture were simulated and the effects of simulated weightlessness on meiotic maturation in mammalian oocytes using mouse as the model system were studied. The timing and frequency of germinal vesicule breakdown and polar body extrusion, and the structural and numerical properties of meiotic chromosomes at Metaphase and Metaphase of meiosis are assessed.
A laboratory investigation of the variability of cloud reflected radiance fields
NASA Technical Reports Server (NTRS)
Mckee, T. B.; Cox, S. K.
1986-01-01
A method to determine the radiative properties of complex cloud fields was developed. A Cloud field optical simulator (CFOS) was constructed to simulate the interaction of cloud fields with visible radiation. The CFOS was verified by comparing experimental results from it with calculations performed with a Monte Carlo radiative transfer model. A software library was developed to process, reduce, and display CFOS data. The CFSOS was utilized to study the reflected radiane patterns from simulated cloud fields.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chrzanowski, P; Walter, K
For the Laboratory and staff, 2006 was a year of outstanding achievements. As our many accomplishments in this annual report illustrate, the Laboratory's focus on important problems that affect our nation's security and our researchers breakthroughs in science and technology have led to major successes. As a national laboratory that is part of the Department of Energy's National Nuclear Security Administration (DOE/NNSA), Livermore is a key contributor to the Stockpile Stewardship Program for maintaining the safety, security, and reliability of the nation's nuclear weapons stockpile. The program has been highly successful, and our annual report features some of the Laboratory'smore » significant stockpile stewardship accomplishments in 2006. A notable example is a long-term study with Los Alamos National Laboratory, which found that weapon pit performance will not sharply degrade from the aging effects on plutonium. The conclusion was based on a wide range of nonnuclear experiments, detailed simulations, theoretical advances, and thorough analyses of the results of past nuclear tests. The study was a superb scientific effort. The continuing success of stockpile stewardship enabled NNSA in 2006 to lay out Complex 2030, a vision for a transformed nuclear weapons complex that is more responsive, cost efficient, and highly secure. One of the ways our Laboratory will help lead this transformation is through the design and development of reliable replacement warheads (RRWs). Compared to current designs, these warheads would have enhanced performance margins and security features and would be less costly to manufacture and maintain in a smaller, modernized production complex. In early 2007, NNSA selected Lawrence Livermore and Sandia National Laboratories-California to develop ''RRW-1'' for the U.S. Navy. Design efforts for the RRW, the plutonium aging work, and many other stockpile stewardship accomplishments rely on computer simulations performed on NNSA's Advanced Simulation and Computing (ASC) Program supercomputers at Livermore. ASC Purple and BlueGene/L, the world's fastest computer, together provide nearly a half petaflop (500 trillion operations per second) of computer power for use by the three NNSA national laboratories. Livermore-led teams were awarded the Gordon Bell Prize for Peak Performance in both 2005 and 2006. The winning simulations, run on BlueGene/L, investigated the properties of materials at the length and time scales of atomic interactions. The computing power that makes possible such detailed simulations provides unprecedented opportunities for scientific discovery. Laboratory scientists are meeting the extraordinary challenge of creating experimental capabilities to match the resolution of supercomputer simulations. Working with a wide range of collaborators, we are developing experimental tools that gather better data at the nanometer and subnanosecond scales. Applications range from imaging biomolecules to studying matter at extreme conditions of pressure and temperature. The premier high-energy-density experimental physics facility in the world will be the National Ignition Facility (NIF) when construction is completed in 2009. We are leading the national effort to perform the first fusion ignition experiments using NIF's 192-beam laser and prepare to explore some of the remaining important issues in weapons physics. With scientific colleagues from throughout the nation, we are also designing revolutionary experiments on NIF to advance the fields of astrophysics, planetary physics, and materials science. Mission-directed, multidisciplinary science and technology at Livermore is also focused on reducing the threat posed by the proliferation of weapons of mass destruction as well as their acquisition and use by terrorists. The Laboratory helps this important national effort by providing its unique expertise, integration analyses, and operational support to the Department of Homeland Security. For this vital facet of the Laboratory's national security mission, we are developing advanced technologies, such as a pocket-size explosives detector and an airborne persistent surveillance system, both of which earned R&D 100 Awards. Altogether, Livermore won seven R&D 100 Awards in 2006, the most for any organization. Emerging threats to national and global security go beyond defense and homeland security. Livermore pursues major scientific and technical advances to meet the need for a clean environment; clean, abundant energy; better water management; and improved human health. Our annual report highlights the link between human activities and the warming of tropical oceans, as well as techniques for imaging biological molecules and detecting bone cancer in its earliest stages. In addition, we showcase many scientific discoveries: distant planets, the composition of comets, a new superheavy element.« less
NASA Astrophysics Data System (ADS)
Rana, K. P. S.; Kumar, Vineet; Mendiratta, Jatin
2017-11-01
One of the most elementary concepts in freshmen Electrical Engineering subject comprises the Resistance-Inductance-Capacitance (RLC) circuit fundamentals, that is, their time and frequency domain responses. For a beginner, generally, it is difficult to understand and appreciate the step and the frequency responses, particularly the resonance. This paper proposes a student-friendly teaching and learning approach by inculcating the multifaceted versatile software LabVIEWTM along with the educational laboratory virtual instrumentation suite hardware, for studying the RLC circuit time and frequency domain responses. The proposed approach has offered an interactive laboratory experiment where students can model circuits in simulation and hardware circuits on prototype board, and then compare their performances. The theoretical simulations and the obtained experimental data are found to be in very close agreement, thereby enhancing the conviction of students. Finally, the proposed methodology was also subjected to the assessment of learning outcomes based on student feedback, and an average score of 8.05 out of 10 with a standard deviation of 0.471 was received, indicating the overall satisfaction of the students.
2016-12-21
STINFO COPY) AIR FORCE RESEARCH LABORATORY MATERIALS AND MANUFACTURING DIRECTORATE WRIGHT-PATTERSON AIR FORCE BASE, OH 45433-7750 AIR FORCE MATERIEL...9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSORING/MONITORING AGENCY ACRONYM(S) Air Force Research Laboratory...removing excess cholesterol from arterial plaques. Gold nanoparticles (AuNPs) functionalized with apolipoprotein A-I and with the lipids 1,2
ERIC Educational Resources Information Center
Frances, J.; Perez-Molina, M.; Bleda, S.; Fernandez, E.; Neipp, C.; Belendez, A.
2012-01-01
Interference and diffraction of light are elementary topics in optics. The aim of the work presented here is to develop an accurate and cheap optical-system simulation software that provides a virtual laboratory for studying the effects of propagation in both time and space for the near- and far-field regions. In laboratory sessions, this software…
SOLPOL: A Solar Polarimeter for Hard X-Rays and Gamma-Rays
NASA Technical Reports Server (NTRS)
McConnell, Michael L.
1999-01-01
Th goal of this project was to continue the development of a hard X-ray polarimeter for studying solar flares. In earlier work (funded by a previous SR&T grant), we had already achieved several goals, including the following: 1) development of a means of producing a polarized radiation source in the lab that could be used for prototype development; 2) demonstrated the basic Compton scatter polarimeter concept using a simple laboratory setup; 3) used the laboratory results to verify our Monte Carlo simulations; and 4) investigated various detector technologies that could be incorporated into the polarimeter design. For the current one-year program, we wanted to fabricate and test a laboratory science model based on our SOLPOL (Solar Polarimeter) design. The long-term goal of this effort is to develop and test a prototype design that could be used to study flare emissions from either a balloon- or space-borne platform. The current program has achieved its goal of fabricating and testing a science model of the SOLPOL design, although additional testing of the design (and detailed comparison with Monte Carlo simulations) is still desired. This one-year program was extended by six months (no-cost extension) to cover the summer of 1999, when undergraduate student support was available to complete some of the laboratory testing.
NASA Astrophysics Data System (ADS)
Perini, Ana P.; Neves, Lucio P.; Maia, Ana F.; Caldas, Linda V. E.
2013-12-01
In this work, a new extended-length parallel-plate ionization chamber was tested in the standard radiation qualities for computed tomography established according to the half-value layers defined at the IEC 61267 standard, at the Calibration Laboratory of the Instituto de Pesquisas Energéticas e Nucleares (IPEN). The experimental characterization was made following the IEC 61674 standard recommendations. The experimental results obtained with the ionization chamber studied in this work were compared to those obtained with a commercial pencil ionization chamber, showing a good agreement. With the use of the PENELOPE Monte Carlo code, simulations were undertaken to evaluate the influence of the cables, insulator, PMMA body, collecting electrode, guard ring, screws, as well as different materials and geometrical arrangements, on the energy deposited on the ionization chamber sensitive volume. The maximum influence observed was 13.3% for the collecting electrode, and regarding the use of different materials and design, the substitutions showed that the original project presented the most suitable configuration. The experimental and simulated results obtained in this work show that this ionization chamber has appropriate characteristics to be used at calibration laboratories, for dosimetry in standard computed tomography and diagnostic radiology quality beams.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zitney, S.E.; McCorkle, D.; Yang, C.
Process modeling and simulation tools are widely used for the design and operation of advanced power generation systems. These tools enable engineers to solve the critical process systems engineering problems that arise throughout the lifecycle of a power plant, such as designing a new process, troubleshooting a process unit or optimizing operations of the full process. To analyze the impact of complex thermal and fluid flow phenomena on overall power plant performance, the Department of Energy’s (DOE) National Energy Technology Laboratory (NETL) has developed the Advanced Process Engineering Co-Simulator (APECS). The APECS system is an integrated software suite that combinesmore » process simulation (e.g., Aspen Plus) and high-fidelity equipment simulations such as those based on computational fluid dynamics (CFD), together with advanced analysis capabilities including case studies, sensitivity analysis, stochastic simulation for risk/uncertainty analysis, and multi-objective optimization. In this paper we discuss the initial phases of the integration of the APECS system with the immersive and interactive virtual engineering software, VE-Suite, developed at Iowa State University and Ames Laboratory. VE-Suite uses the ActiveX (OLE Automation) controls in the Aspen Plus process simulator wrapped by the CASI library developed by Reaction Engineering International to run process/CFD co-simulations and query for results. This integration represents a necessary step in the development of virtual power plant co-simulations that will ultimately reduce the time, cost, and technical risk of developing advanced power generation systems.« less
The Development and Deployment of a Virtual Unit Operations Laboratory
ERIC Educational Resources Information Center
Vaidyanath, Sreeram; Williams, Jason; Hilliard, Marcus; Wiesner, Theodore
2007-01-01
Computer-simulated experiments offer many benefits to engineering curricula in the areas of safety, cost, and flexibility. We report our experience in developing and deploying a computer-simulated unit operations laboratory, driven by the guiding principle of maximum fidelity to the physical lab. We find that, while the up-front investment in…
Laboratory simulation of organic geochemical processes.
NASA Technical Reports Server (NTRS)
Eglinton, G.
1972-01-01
Discussion of laboratory simulations that are important to organic geochemistry in that they provide direct evidence relating to geochemical cycles involving carbon. Reviewed processes and experiments include reactions occurring in the geosphere, particularly, short-term diagenesis of biolipids and organochlorine pesticides in estuarine muds, as well as maturation of organic matter in ancient sediments.
Open Simulation Laboratories [Guest editors' introduction
Alexander, Francis J.; Meneveau, Charles
2015-09-01
The introduction for the special issue on open simulation laboratories, the guest editors describe how OSLs will become more common as their potential is better understood and they begin providing access to valuable datasets to much larger segments of the scientific community. Moreover, new analysis tools and ways to do science will inevitably develop as a result.
A Funding Simulation for Use in an Advanced Experimental Laboratory Class.
ERIC Educational Resources Information Center
Falkenberg, Virginia P.
1981-01-01
Describes a funding simulation for use with college students in an advanced experimental psychology laboratory. Students write an original research paper and submit it to the professor--the "funding agency"--as a grant proposal. Projects are funded with grade points with which the student director purchases help from unfunded classmates. (RM)
Best, Virginia; Keidser, Gitte; Buchholz, Jörg M; Freeston, Katrina
2015-01-01
There is increasing demand in the hearing research community for the creation of laboratory environments that better simulate challenging real-world listening environments. The hope is that the use of such environments for testing will lead to more meaningful assessments of listening ability, and better predictions about the performance of hearing devices. Here we present one approach for simulating a complex acoustic environment in the laboratory, and investigate the effect of transplanting a speech test into such an environment. Speech reception thresholds were measured in a simulated reverberant cafeteria, and in a more typical anechoic laboratory environment containing background speech babble. The participants were 46 listeners varying in age and hearing levels, including 25 hearing-aid wearers who were tested with and without their hearing aids. Reliable SRTs were obtained in the complex environment, but led to different estimates of performance and hearing-aid benefit from those measured in the standard environment. The findings provide a starting point for future efforts to increase the real-world relevance of laboratory-based speech tests.
Microscopic modeling of nitride intersubband absorbance
NASA Astrophysics Data System (ADS)
Montano, Ines; Allerman, A. A.; Wierer, J. J.; Moseley, M.; Skogen, E. J.; Tauke-Pedretti, A.; Vawter, G. A.
III-nitride intersubband structures have recently attracted much interest because of their potential for a wide variety of applications ranging from electro-optical modulators to terahertz quantum cascade lasers. To overcome present simulation limitations we have developed a microscopic absorbance simulator for nitride intersubband devices. Our simulator calculates the band structure of nitride intersubband systems using a fully coupled 8x8 k.p Hamiltonian and determines the material response of a single period in a density-matrix-formalism by solving the Heisenberg equation including many-body and dephasing contributions. After calculating the polarization due to intersubband transitions in a single period, the resulting absorbance of a superlattice structure including radiative coupling between the different periods is determined using a non-local Green's-function formalism. As a result our simulator allows us to predict intersubband absorbance of superlattice structures with microscopically determined lineshapes and linewidths accounting for both many-body and correlation contributions. This work is funded by Sandia National Laboratories Laboratory Directed Research and Development program. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin.
Integration of Dakota into the NEAMS Workbench
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swiler, Laura Painton; Lefebvre, Robert A.; Langley, Brandon R.
2017-07-01
This report summarizes a NEAMS (Nuclear Energy Advanced Modeling and Simulation) project focused on integrating Dakota into the NEAMS Workbench. The NEAMS Workbench, developed at Oak Ridge National Laboratory, is a new software framework that provides a graphical user interface, input file creation, parsing, validation, job execution, workflow management, and output processing for a variety of nuclear codes. Dakota is a tool developed at Sandia National Laboratories that provides a suite of uncertainty quantification and optimization algorithms. Providing Dakota within the NEAMS Workbench allows users of nuclear simulation codes to perform uncertainty and optimization studies on their nuclear codes frommore » within a common, integrated environment. Details of the integration and parsing are provided, along with an example of Dakota running a sampling study on the fuels performance code, BISON, from within the NEAMS Workbench.« less
NASA Astrophysics Data System (ADS)
Boruah, Manash J.; Ahmed, Gazi A.
2018-01-01
Laser based experimental light scattering studies of irregularly shaped silica microparticles have been performed at three incident wavelengths 543.5 nm, 594.5 nm and 632.8 nm supported by laboratory based computations and 3D realistic simulations, using an indigenously fabricated light scattering setup. A comparative analysis of the computational and experimentally acquired results is done and a good agreement is found in the forward scattering lobes in all cases for each of the measured scattering parameters. This study also provides an efficient way of detecting and measuring particle size distribution for irregular micro- and nanoparticles and is highly applicable in remote sensing, atmospheric, astrophysical, and medical applications and also for finding potential health hazards in the form of inhalable and respirable small particulate matter.
NASA Astrophysics Data System (ADS)
Paulides, M. M.; Bakker, J. F.; Hofstetter, L. W.; Numan, W. C. M.; Pellicer, R.; Fiveland, E. W.; Tarasek, M.; Houston, G. C.; van Rhoon, G. C.; Yeo, D. T. B.; Kotek, G.
2014-05-01
Clinical studies have established a strong benefit from adjuvant mild hyperthermia (HT) to radio- and chemotherapy for many tumor sites, including the head and neck (H&N). The recently developed HYPERcollar allows the application of local radiofrequency HT to tumors in the entire H&N. Treatment quality is optimized using electromagnetic and thermal simulators and, whenever placement risk is tolerable, assessed using invasively placed thermometers. To replace the current invasive procedure, we are investigating whether magnetic resonance (MR) thermometry can be exploited for continuous and 3D thermal dose assessment. In this work, we used our simulation tools to design an MR compatible laboratory prototype applicator. By simulations and measurements, we showed that the redesigned patch antennas are well matched to 50 Ω (S11<-10 dB). Simulations also show that, using 300 W input power, a maximum specific absorption rate (SAR) of 100 W kg-1 and a temperature increase of 4.5 °C in 6 min is feasible at the center of a cylindrical fat/muscle phantom. Temperature measurements using the MR scanner confirmed the focused heating capabilities and MR compatibility of the setup. We conclude that the laboratory applicator provides the possibility for experimental assessment of the feasibility of hybrid MR-HT in the H&N region. This versatile design allows rigorous analysis of MR thermometry accuracy in increasingly complex phantoms that mimic patients' anatomies and thermodynamic characteristics.
Observations and laboratory simulations of tornadoes in complex topographical regions
NASA Astrophysics Data System (ADS)
Karstens, Christopher Daniel
Aerial photos taken along the damage paths of the Joplin, MO, and Tuscaloosa-Birmingham, AL, tornadoes of 2011 captured and preserved several unique patterns of damage. In particular, a few distinct tree-fall patterns were noted along the Tuscaloosa-Birmingham tornado track that appeared highly influenced by the underlying topography. One such region was the focus of a damage survey and motivated laboratory vortex simulations with a 3-D foam representation of the underlying topography, in addition to simulations performed with idealized 2D topographic features, using Iowa State University's tornado simulator. The purpose of this dissertation is to explore various aspects related to the interaction of a tornado or a tornado-like vortex with its underlying topography. Three topics are examined: 1) Analysis of tornado-induced tree-fall using aerial photography from the Joplin, MO, and Tuscaloosa-Birmingham, AL, tornadoes of 2011, 2) Laboratory investigation of topographical influences on a simulated tornado-like vortex, and 3) On the use of non-standard EF-scale damage indicators to categorize tornadoes.
NASA Astrophysics Data System (ADS)
Zainol, M. R. R. M. A.; Kamaruddin, M. A.; Zawawi, M. H.; Wahab, K. A.
2017-11-01
Smooth Particle Hydrodynamic is the three-dimensional (3D) model. In this research work, three cases and one validation have been simulate using DualSPHysics. Study area of this research work was at Sarawak Barrage. The cases have different water level at the downstream. This study actually to simulate riverbed erosion and scouring properties by using multi-phases cases which use sand as sediment and water. The velocity and the scouring profile have been recorded as the result and shown in the result chapter. The result of the validation is acceptable where the scouring profile and the velocity were slightly different between laboratory experiment and simulation. Hence, it can be concluded that the simulation by using SPH can be used as the alternative to simulate the real cases.
Laboratory simulation of space plasma phenomena*
NASA Astrophysics Data System (ADS)
Amatucci, B.; Tejero, E. M.; Ganguli, G.; Blackwell, D.; Enloe, C. L.; Gillman, E.; Walker, D.; Gatling, G.
2017-12-01
Laboratory devices, such as the Naval Research Laboratory's Space Physics Simulation Chamber, are large-scale experiments dedicated to the creation of large-volume plasmas with parameters realistically scaled to those found in various regions of the near-Earth space plasma environment. Such devices make valuable contributions to the understanding of space plasmas by investigating phenomena under carefully controlled, reproducible conditions, allowing for the validation of theoretical models being applied to space data. By working in collaboration with in situ experimentalists to create realistic conditions scaled to those found during the observations of interest, the microphysics responsible for the observed events can be investigated in detail not possible in space. To date, numerous investigations of phenomena such as plasma waves, wave-particle interactions, and particle energization have been successfully performed in the laboratory. In addition to investigations such as plasma wave and instability studies, the laboratory devices can also make valuable contributions to the development and testing of space plasma diagnostics. One example is the plasma impedance probe developed at NRL. Originally developed as a laboratory diagnostic, the sensor has now been flown on a sounding rocket, is included on a CubeSat experiment, and will be included on the DoD Space Test Program's STP-H6 experiment on the International Space Station. In this presentation, we will describe several examples of the laboratory investigation of space plasma waves and instabilities and diagnostic development. *This work supported by the NRL Base Program.
Molecular-Level Simulations of the Turbulent Taylor-Green Flow
NASA Astrophysics Data System (ADS)
Gallis, M. A.; Bitter, N. P.; Koehler, T. P.; Plimpton, S. J.; Torczynski, J. R.; Papadakis, G.
2017-11-01
The Direct Simulation Monte Carlo (DSMC) method, a statistical, molecular-level technique that provides accurate solutions to the Boltzmann equation, is applied to the turbulent Taylor-Green vortex flow. The goal of this work is to investigate whether DSMC can accurately simulate energy decay in a turbulent flow. If so, then simulating turbulent flows at the molecular level can provide new insights because the energy decay can be examined in detail from molecular to macroscopic length scales, thereby directly linking molecular relaxation processes to macroscopic transport processes. The DSMC simulations are performed on half a million cores of Sequoia, the 17 Pflop platform at Lawrence Livermore National Laboratory, and the kinetic-energy dissipation rate and the energy spectrum are computed directly from the molecular velocities. The DSMC simulations are found to reproduce the Kolmogorov -5/3 law and to agree with corresponding Navier-Stokes simulations obtained using a spectral method. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arnold H. Kritz
PTRANSP, which is the predictive version of the TRANSP code, was developed in a collaborative effort involving the Princeton Plasma Physics Laboratory, General Atomics Corporation, Lawrence Livermore National Laboratory, and Lehigh University. The PTRANSP/TRANSP suite of codes is the premier integrated tokamak modeling software in the United States. A production service for PTRANSP/TRANSP simulations is maintained at the Princeton Plasma Physics Laboratory; the server has a simple command line client interface and is subscribed to by about 100 researchers from tokamak projects in the US, Europe, and Asia. This service produced nearly 13000 PTRANSP/TRANSP simulations in the four year periodmore » FY 2005 through FY 2008. Major archives of TRANSP results are maintained at PPPL, MIT, General Atomics, and JET. Recent utilization, counting experimental analysis simulations as well as predictive simulations, more than doubled from slightly over 2000 simulations per year in FY 2005 and FY 2006 to over 4300 simulations per year in FY 2007 and FY 2008. PTRANSP predictive simulations applied to ITER increased eight fold from 30 simulations per year in FY 2005 and FY 2006 to 240 simulations per year in FY 2007 and FY 2008, accounting for more than half of combined PTRANSP/TRANSP service CPU resource utilization in FY 2008. PTRANSP studies focused on ITER played a key role in journal articles. Examples of validation studies carried out for momentum transport in PTRANSP simulations were presented at the 2008 IAEA conference. The increase in number of PTRANSP simulations has continued (more than 7000 TRANSP/PTRANSP simulations in 2010) and results of PTRANSP simulations appear in conference proceedings, for example the 2010 IAEA conference, and in peer reviewed papers. PTRANSP provides a bridge to the Fusion Simulation Program (FSP) and to the future of integrated modeling. Through years of widespread usage, each of the many parts of the PTRANSP suite of codes has been thoroughly validated against experimental data and benchmarked against other codes. At the same time, architectural modernizations are improving the modularity of the PTRANSP code base. The NUBEAM neutral beam and fusion products fast ion model, the Plasma State data repository (developed originally in the SWIM SciDAC project and adapted for use in PTRANSP), and other components are already shared with the SWIM, FACETS, and CPES SciDAC FSP prototype projects. Thus, the PTRANSP code is already serving as a bridge between our present integrated modeling capability and future capability. As the Fusion Simulation Program builds toward the facility currently available in the PTRANSP suite of codes, early versions of the FSP core plasma model will need to be benchmarked against the PTRANSP simulations. This will be necessary to build user confidence in FSP, but this benchmarking can only be done if PTRANSP itself is maintained and developed.« less
Studying the Binomial Distribution Using LabVIEW
ERIC Educational Resources Information Center
George, Danielle J.; Hammer, Nathan I.
2015-01-01
This undergraduate physical chemistry laboratory exercise introduces students to the study of probability distributions both experimentally and using computer simulations. Students perform the classic coin toss experiment individually and then pool all of their data together to study the effect of experimental sample size on the binomial…
Jabor, A; Vlk, T; Boril, P
1996-04-15
We designed a simulation model for the assessment of the financial risks involved when a new diagnostic test is introduced in the laboratory. The model is based on a neural network consisting of ten neurons and assumes that input entities can have assigned appropriate uncertainty. Simulations are done on a 1-day interval basis. Risk analysis completes the model and the financial effects are evaluated for a selected time period. The basic output of the simulation consists of total expenses and income during the simulation time, net present value of the project at the end of simulation, total number of control samples during simulation, total number of patients evaluated and total number of used kits.
Examining System-Wide Impacts of Solar PV Control Systems with a Power Hardware-in-the-Loop Platform
DOE Office of Scientific and Technical Information (OSTI.GOV)
Williams, Tess L.; Fuller, Jason C.; Schneider, Kevin P.
2014-06-08
High penetration levels of distributed solar PV power generation can lead to adverse power quality impacts, such as excessive voltage rise, voltage flicker, and reactive power values that result in unacceptable voltage levels. Advanced inverter control schemes have been developed that have the potential to mitigate many power quality concerns. However, local closed-loop control may lead to unintended behavior in deployed systems as complex interactions can occur between numerous operating devices. To enable the study of the performance of advanced control schemes in a detailed distribution system environment, a test platform has been developed that integrates Power Hardware-in-the-Loop (PHIL) withmore » concurrent time-series electric distribution system simulation. In the test platform, GridLAB-D, a distribution system simulation tool, runs a detailed simulation of a distribution feeder in real-time mode at the Pacific Northwest National Laboratory (PNNL) and supplies power system parameters at a point of common coupling. At the National Renewable Energy Laboratory (NREL), a hardware inverter interacts with grid and PV simulators emulating an operational distribution system. Power output from the inverters is measured and sent to PNNL to update the real-time distribution system simulation. The platform is described and initial test cases are presented. The platform is used to study the system-wide impacts and the interactions of inverter control modes—constant power factor and active Volt/VAr control—when integrated into a simulated IEEE 8500-node test feeder. We demonstrate that this platform is well-suited to the study of advanced inverter controls and their impacts on the power quality of a distribution feeder. Additionally, results are used to validate GridLAB-D simulations of advanced inverter controls.« less
Flight Simulator Evaluation of Baseline Crew Performances With Three Data Link Interfaces
DOT National Transportation Integrated Search
1995-09-01
This study was conducted by the National Laboratory for Research of the : Netherlands under cooperative sponsorship by the Federal Aviation Administration : (FAA), and the Ministry of Transport of the Netherlands. The purpose of the : study was the e...
A survey of electric and hybrid vehicles simulation programs. Volume 2: Questionnaire responses
NASA Technical Reports Server (NTRS)
Bevan, J.; Heimburger, D. A.; Metcalfe, M. A.
1978-01-01
The data received in a survey conducted within the United States to determine the extent of development and capabilities of automotive performance simulation programs suitable for electric and hybrid vehicle studies are presented. The survey was conducted for the Department of Energy by NASA's Jet Propulsion Laboratory. Volume 1 of this report summarizes and discusses the results contained in Volume 2.
The Scientific Program of the U.S. Naval Research Laboratory
1958-07-01
systems, using mock-ups and simulated inputs. (2) Experimental determination of the quantitative parameters of systems, such as data-handling ability, time...naval service of equipment on ships, planes, and mis- siles are recorded, analyzed, and simulated . Methods are developed for the improve- ment of...H01 - NUCLEAR CONSTITUENTS AND STRUCTURE Theoretical and experimental studies concerned with elementary particles , field theory, nuclear structure
NASA Technical Reports Server (NTRS)
Bartkus, Tadas; Tsao, Jen-Ching; Struk, Peter
2017-01-01
This paper builds on previous work that compares numerical simulations of mixed-phase icing clouds with experimental data. The model couples the thermal interaction between ice particles and water droplets of the icing cloud with the flowing air of an icing wind tunnel for simulation of NASA Glenn Research Centers (GRC) Propulsion Systems Laboratory (PSL). Measurements were taken during the Fundamentals of Ice Crystal Icing Physics Tests at the PSL tunnel in March 2016. The tests simulated ice-crystal and mixed-phase icing that relate to ice accretions within turbofan engines.
Laboratory and Workplace Assessments of Rivet Bucking Bar Vibration Emissions
McDowell, Thomas W.; Warren, Christopher; Xu, Xueyan S.; Welcome, Daniel E.; Dong, Ren G.
2016-01-01
Sheet metal workers operating rivet bucking bars are at risk of developing hand and wrist musculoskeletal disorders associated with exposures to hand-transmitted vibrations and forceful exertions required to operate these hand tools. New bucking bar technologies have been introduced in efforts to reduce workplace vibration exposures to these workers. However, the efficacy of these new bucking bar designs has not been well documented. While there are standardized laboratory-based methodologies for assessing the vibration emissions of many types of powered hand tools, no such standard exists for rivet bucking bars. Therefore, this study included the development of a laboratory-based method for assessing bucking bar vibrations which utilizes a simulated riveting task. With this method, this study evaluated three traditional steel bucking bars, three similarly shaped tungsten alloy bars, and three bars featuring spring-dampeners. For comparison the bucking bar vibrations were also assessed during three typical riveting tasks at a large aircraft maintenance facility. The bucking bars were rank-ordered in terms of unweighted and frequency-weighted acceleration measured at the hand-tool interface. The results suggest that the developed laboratory method is a reasonable technique for ranking bucking bar vibration emissions; the lab-based riveting simulations produced similar rankings to the workplace rankings. However, the laboratory-based acceleration averages were considerably lower than the workplace measurements. These observations suggest that the laboratory test results are acceptable for comparing and screening bucking bars, but the laboratory measurements should not be directly used for assessing the risk of workplace bucking bar vibration exposures. The newer bucking bar technologies exhibited significantly reduced vibrations compared to the traditional steel bars. The results of this study, together with other information such as rivet quality, productivity, tool weight, comfort, worker acceptance, and initial cost can be used to make informed bucking bar selections. PMID:25381185
Laboratory and workplace assessments of rivet bucking bar vibration emissions.
McDowell, Thomas W; Warren, Christopher; Xu, Xueyan S; Welcome, Daniel E; Dong, Ren G
2015-04-01
Sheet metal workers operating rivet bucking bars are at risk of developing hand and wrist musculoskeletal disorders associated with exposures to hand-transmitted vibrations and forceful exertions required to operate these hand tools. New bucking bar technologies have been introduced in efforts to reduce workplace vibration exposures to these workers. However, the efficacy of these new bucking bar designs has not been well documented. While there are standardized laboratory-based methodologies for assessing the vibration emissions of many types of powered hand tools, no such standard exists for rivet bucking bars. Therefore, this study included the development of a laboratory-based method for assessing bucking bar vibrations which utilizes a simulated riveting task. With this method, this study evaluated three traditional steel bucking bars, three similarly shaped tungsten alloy bars, and three bars featuring spring-dampeners. For comparison the bucking bar vibrations were also assessed during three typical riveting tasks at a large aircraft maintenance facility. The bucking bars were rank-ordered in terms of unweighted and frequency-weighted acceleration measured at the hand-tool interface. The results suggest that the developed laboratory method is a reasonable technique for ranking bucking bar vibration emissions; the lab-based riveting simulations produced similar rankings to the workplace rankings. However, the laboratory-based acceleration averages were considerably lower than the workplace measurements. These observations suggest that the laboratory test results are acceptable for comparing and screening bucking bars, but the laboratory measurements should not be directly used for assessing the risk of workplace bucking bar vibration exposures. The newer bucking bar technologies exhibited significantly reduced vibrations compared to the traditional steel bars. The results of this study, together with other information such as rivet quality, productivity, tool weight, comfort, worker acceptance, and initial cost can be used to make informed bucking bar selections. Published by Oxford University Press on behalf of the British Occupational Hygiene Society 2014.
Innovative mathematical modeling in environmental remediation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yeh, Gour T.; National Central Univ.; Univ. of Central Florida
2013-05-01
There are two different ways to model reactive transport: ad hoc and innovative reaction-based approaches. The former, such as the Kd simplification of adsorption, has been widely employed by practitioners, while the latter has been mainly used in scientific communities for elucidating mechanisms of biogeochemical transport processes. It is believed that innovative mechanistic-based models could serve as protocols for environmental remediation as well. This paper reviews the development of a mechanistically coupled fluid flow, thermal transport, hydrologic transport, and reactive biogeochemical model and example-applications to environmental remediation problems. Theoretical bases are sufficiently described. Four example problems previously carried out aremore » used to demonstrate how numerical experimentation can be used to evaluate the feasibility of different remediation approaches. The first one involved the application of a 56-species uranium tailing problem to the Melton Branch Subwatershed at Oak Ridge National Laboratory (ORNL) using the parallel version of the model. Simulations were made to demonstrate the potential mobilization of uranium and other chelating agents in the proposed waste disposal site. The second problem simulated laboratory-scale system to investigate the role of natural attenuation in potential off-site migration of uranium from uranium mill tailings after restoration. It showed inadequacy of using a single Kd even for a homogeneous medium. The third example simulated laboratory experiments involving extremely high concentrations of uranium, technetium, aluminum, nitrate, and toxic metals (e.g.,Ni, Cr, Co).The fourth example modeled microbially-mediated immobilization of uranium in an unconfined aquifer using acetate amendment in a field-scale experiment. The purposes of these modeling studies were to simulate various mechanisms of mobilization and immobilization of radioactive wastes and to illustrate how to apply reactive transport models for environmental remediation.The second problem simulated laboratory-scale system to investigate the role of natural attenuation in potential off-site migration of uranium from uranium mill tailings after restoration. It showed inadequacy of using a single Kd even for a homogeneous medium.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Berenbrock, C.; Kjelstrom, L.C.
1997-10-01
Delineation of areas at the Idaho National Engineering and Environmental Laboratory that would be inundated by a 100-year peak flow in Birch Creek is needed by the US Department of Energy to fulfill flood-plain regulatory requirements. Birch Creek flows southward about 40 miles through an alluvium-filled valley onto the northern part of the Idaho National Engineering and Environmental laboratory site on the eastern Snake River Plain. The lower 10-mile reach of Birch Creek that ends in Birch Creek Playa near several Idaho National Engineering and Environmental Laboratory facilities is of particular concern. Twenty-six channel cross sections were surveyed to developmore » and apply a hydraulic model to simulate water-surface elevations for a hypothetical 100-year peak flow in Birch Creek. Model simulation of the 100-year peak flow (700 cubic feet per second) in reaches upstream from State Highway 22 indicated that flow was confined within channels even when all flow was routed to one channel. Where the highway crosses Birch Creek, about 315 cubic feet per second of water was estimated to move downstream--115 cubic feet per second through a culvert and 200 cubic feet per second over the highway. Simulated water-surface elevation at this crossing was 0.8 foot higher than the elevation of the highway. The remaining 385 cubic feet per second flowed southwestward in a trench along the north side of the highway. Flow also was simulated with the culvert removed. The exact location of flood boundaries on Birch Creek could not be determined because of the highly braided channel and the many anthropogenic features (such as the trench, highway, and diversion channels) in the study area that affect flood hydraulics and flow. Because flood boundaries could not be located exactly, only a generalized flood-prone map was developed.« less
NASA Technical Reports Server (NTRS)
Groom, N. J.; Woolley, C. T.; Joshi, S. M.
1981-01-01
A linear analysis and the results of a nonlinear simulation of a magnetic bearing suspension system which uses permanent magnet flux biasing are presented. The magnetic bearing suspension is part of a 4068 N-m-s (3000 lb-ft-sec) laboratory model annular momentum control device (AMCD). The simulation includes rigid body rim dynamics, linear and nonlinear axial actuators, linear radial actuators, axial and radial rim warp, and power supply and power driver current limits.
Modeling laser-plasma acceleration in the laboratory frame
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2011-01-01
A simulation of laser-plasma acceleration in the laboratory frame. Both the laser and the wakefield buckets must be resolved over the entire domain of the plasma, requiring many cells and many time steps. While researchers often use a simulation window that moves with the pulse, this reduces only the multitude of cells, not the multitude of time steps. For an artistic impression of how to solve the simulation by using the boosted-frame method, watch the video "Modeling laser-plasma acceleration in the wakefield frame".
Rules of good practice in the care of laboratory animals used in biomedical research.
Valanzano, Angelina
2004-01-01
In recent years, the use of laboratory animals has decreased as a result of the adoption of alternative methods such as in vitro experiments and simulation studies. Nonetheless, animal models continue to be necessary in many fields of biomedical research, giving rise to ethical issues regarding the treatment of these animals. In the present work, a general overview of the rules of good practise in caring for laboratory animals is provided, focussing on housing conditions and the proper means of handling animals, including the importance of the relationship or "bond" between the researcher and the animal.
Radar research at The Pennsylvania State University Radar and Communications Laboratory
NASA Astrophysics Data System (ADS)
Narayanan, Ram M.
2017-05-01
The Radar and Communications Laboratory (RCL) at The Pennsylvania State University is at the forefront of radar technology and is engaged in cutting edge research in all aspects of radar, including modeling and simulation studies of novel radar paradigms, design and development of new types of radar architectures, and extensive field measurements in realistic scenarios. This paper summarizes the research at The Pennsylvania State University's Radar and Communications Laboratory and relevant collaborative research with several groups over the past 15 years in the field of radar and related technologies, including communications, radio frequency identification (RFID), and spectrum sensing.
Astromaterials Research Office (KR) Overview
NASA Technical Reports Server (NTRS)
Draper, David S.
2014-01-01
The fundamental goal of our research is to understand the origin and evolution of the solar system, particularly the terrestrial, "rocky" bodies. Our research involves analysis of, and experiments on, astromaterials in order to understand their nature, sources, and processes of formation. Our state-of-the-art analytical laboratories include four electron microbeam laboratories for mineral analysis, four spectroscopy laboratories for chemical and mineralogical analysis, and four mass spectrometry laboratories for isotopic analysis. Other facilities include the experimental impact laboratory and both 1-atm gas mixing and high-pressure experimental petrology laboratories. Recent research has emphasized a diverse range of topics, including: Study of the solar system's primitive materials, such as carbonaceous chondrites and interplanetary dust; Study of early solar system chronology using short-lived radioisotopes and early nebular processes through detailed geochemical and isotopic characterizations; Study of large-scale planetary differentiation and evolution via siderophile and incompatible trace element partitioning, magma ocean crystallization simulations, and isotopic systematics; Study of the petrogenesis of Martian meteorites through petrographic, isotopic, chemical, and experimental melting and crystallization studies; Interpretation of remote sensing data, especially from current robotic lunar and Mars missions, and study of terrestrial analog materials; Study of the role of organic geochemical processes in the evolution of astromaterials and the extent to which they constrain the potential for habitability and the origin of life.
NASA Astrophysics Data System (ADS)
Cockell, C. S.; Lim, D. S. S.; Braham, S.; Lee, P.; Clancey, B.
The search for life (or the examination of the reasons for its absence) is one of the most compelling scientific activities on Mars. We describe the study of the microbiology of the Haughton impact crater in the Canadian Arctic, from a simulated Mars lander (the FMARS). Impact events have had a profound influence on Mars, and thus on any putative microbial habitats that future explorers might seek. The study of microbial habitats was accomplished under simulated EVA time constraints and with simulated Mars communications. The work was catalogued to develop a computer model for Mars mission planning - `Brahms'. We implemented a program of cosmic ray dosimeter deployment and we describe how sampling of paleolake deposits might be accomplished from a lander. We domonstrate that science on the surface of Mars can be accomplished from the testing of hypotheses through to the preparation of peer-reviewed manuscripts during a long-duration stay, a significant difference to merely sampling as on the Apollo expeditions. The design of a Martian surface exobiology laboratory is described.
Monte Carlo study of a 60Co calibration field of the Dosimetry Laboratory Seibersdorf.
Hranitzky, C; Stadtmann, H
2007-01-01
The gamma radiation fields of the reference irradiation facility of the Dosimetry Laboratory Seibersdorf with collimated beam geometry are used for calibrating radiation protection dosemeters. A close-to-reality simulation model of the facility including the complex geometry of a 60Co source was set up using the Monte Carlo code MCNP. The goal of this study is to characterise the radionuclide gamma calibration field and resulting air-kerma distributions inside the measurement hall with a total of 20 m in length. For the whole range of source-detector-distances (SDD) along the central beam axis, simulated and measured relative air-kerma values are within +/-0.6%. Influences on the accuracy of the simulation results are investigated, including e.g., source mass density effects or detector volume dependencies. A constant scatter contribution from the lead ring-collimator of approximately 1% and an increasing scatter contribution from the concrete floor for distances above 7 m are identified, resulting in a total air-kerma scatter contribution below 5%, which is in accordance to the ISO 4037-1 recommendations.
ERIC Educational Resources Information Center
Matheny, W. G.; And Others
The document presents a summary description of the Air Force Human Resource Laboratory's Flying Training Division (AFHRL/FT) research capabilities for undergraduate pilot training. One of the research devices investigated is the Advanced Simulator for Undergraduate Pilot Training (ASUPT). The equipment includes the ASUPT, the instrumented T-37…
The WEBSIM FISHBANKS Simulation Laboratory: Analysis of Its Ripple Effects
ERIC Educational Resources Information Center
Arantes do Amaral, João Alberto; Hess, Aurélio
2018-01-01
In this article, we discuss the ripple effects of the WEBSIM FISHBANKS Simulation Laboratory held at Federal University of Sao Paulo (UNIFESP) in 2014, held as a result of a partnership between the Sloan School of Management of the Massachusetts Institute of Technology, the UNIFESP, and the Brazilian Chapter of the System Dynamics Society of…
Closely Spaced Independent Parallel Runway Simulation.
1984-10-01
facility consists of the Central Computer Facility, the Controller Laboratory, and the Simulator Pilot Complex. CENTRAL COMPUTER FACILITY. The Central... Computer Facility consists of a group of mainframes, minicomputers, and associated peripherals which host the operational and data acquisition...in the Controller Laboratory and convert their verbal directives into a keyboard entry which is transmitted to the Central Computer Complex, where
NASA Astrophysics Data System (ADS)
Cheng, D. L. C.; Quinn, J. D.; Larour, E. Y.; Halkides, D. J.
2017-12-01
The Virtual Earth System Laboratory (VESL) is a Web application, under continued development at the Jet Propulsion Laboratory and UC Irvine, for the visualization of Earth System data and process simulations. As with any project of its size, we have encountered both successes and challenges during the course of development. Our principal point of success is the fact that VESL users can interact seamlessly with our earth science simulations within their own Web browser. Some of the challenges we have faced include retrofitting the VESL Web application to respond to touch gestures, reducing page load time (especially as the application has grown), and accounting for the differences between the various Web browsers and computing platforms.
ERIC Educational Resources Information Center
Anthony, Seth
2014-01-01
Part I: Students' participation in inquiry-based chemistry laboratory curricula, and, in particular, engagement with key thinking processes in conjunction with these experiences, is linked with success at the difficult task of "transfer"--applying their knowledge in new contexts to solve unfamiliar types of problems. We investigate…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fox, K. M.; Edwards, T. B.; Caldwell, M. E.
In this report, the Savannah River National Laboratory (SRNL) provides chemical analyses and Product Consistency Test (PCT) results for a series of simulated high-level waste glass compositions fabricated by the Pacific Northwest National Laboratory (PNNL). These data will be used in the development of improved models for the prediction of nepheline crystallization in support of the Hanford Tank Waste Treatment and Immobilization Plant (WTP).
Jelacic, Srdjan; Bowdle, Andrew; Togashi, Kei; VonHomeyer, Peter
2013-08-01
The authors evaluated the educational benefits of using a first-generation HeartWorks simulator to teach senior anesthesiology residents basic echocardiography skills. Prospective observational study. A single academic medical center (teaching hospital). Thirty-seven senior (fourth-year) anesthesiology residents participated in this study. Groups of 3 senior anesthesiology residents participated in a single 3-hour tutorial in the simulation laboratory in the authors' institution during their cardiothoracic anesthesiology rotation. A cardiothoracic anesthesiology faculty member demonstrated the use of the transesophageal echocardiography (TEE) simulator and instructed the residents on obtaining standard TEE views of normal anatomy. Prior to the laboratory session, the residents took an online multiple-choice pretest with 25 questions related to safety, probe manipulation, clinical application, and pathology, which was accompanied by echo images of normal cardiac anatomy and video clips of pathology. Three to four weeks after the TEE tutorial, the residents completed an online post-test and evaluation of the teaching session. There was a statistically significant increase in knowledge of normal echocardiographic anatomy (p = 0.04), with an average improvement in normal echocardiographic anatomy scores of 15%. Virtual reality TEE simulation technology was endorsed strongly by residents, produced a statistically significant improvement in knowledge of normal echocardiographic anatomy, and could be effective for teaching basic echocardiography to anesthesiology residents. Copyright © 2013 Elsevier Inc. All rights reserved.
Bischof, Jason J; Panchal, Ashish R; Finnegan, Geoffrey I; Terndrup, Thomas E
2016-10-01
Introduction Endotracheal intubation (ETI) is a complex clinical skill complicated by the inherent challenge of providing care in the prehospital setting. Literature reports a low success rate of prehospital ETI attempts, partly due to the care environment and partly to the lack of consistent standardized training opportunities of prehospital providers in ETI. Hypothesis/Problem The availability of a mobile simulation laboratory (MSL) to study clinically critical interventions is needed in the prehospital setting to enhance instruction and maintain proficiency. This report is on the development and validation of a prehospital airway simulator and MSL that mimics in situ care provided in an ambulance. The MSL was a Type 3 ambulance with four cameras allowing audio-video recordings of observable behaviors. The prehospital airway simulator is a modified airway mannequin with increased static tongue pressure and a rigid cervical collar. Airway experts validated the model in a static setting through ETI at varying tongue pressures with a goal of a Grade 3 Cormack-Lehane (CL) laryngeal view. Following completion of this development, the MSL was launched with the prehospital airway simulator to distant communities utilizing a single facilitator/driver. Paramedics were recruited to perform ETI in the MSL, and the detailed airway management observations were stored for further analysis. Nineteen airway experts performed 57 ETI attempts at varying tongue pressures demonstrating increased CL views at higher tongue pressures. Tongue pressure of 60 mm Hg generated 31% Grade 3/4 CL view and was chosen for the prehospital trials. The MSL was launched and tested by 18 paramedics. First pass success was 33% with another 33% failing to intubate within three attempts. The MSL created was configured to deliver, record, and assess intubator behaviors with a difficult airway simulation. The MSL created a reproducible, high fidelity, mobile learning environment for assessment of simulated ETI performance by prehospital providers. Bischof JJ , Panchal AR , Finnegan GI , Terndrup TE . Creation and validation of a novel mobile simulation laboratory for high fidelity, prehospital, difficult airway simulation. Prehosp Disaster Med. 2016;31(5):465-470.
Diwakar, Shyam; Parasuram, Harilal; Medini, Chaitanya; Raman, Raghu; Nedungadi, Prema; Wiertelak, Eric; Srivastava, Sanjeeva; Achuthan, Krishnashree; Nair, Bipin
2014-01-01
Classroom-level neuroscience experiments vary from detailed protocols involving chemical, physiological and imaging techniques to computer-based modeling. The application of Information and Communication Technology (ICT) is revolutionizing the current laboratory scenario in terms of active learning especially for distance education cases. Virtual web-based labs are an asset to educational institutions confronting economic issues in maintaining equipment, facilities and other conditions needed for good laboratory practice. To enhance education, we developed virtual laboratories in neuroscience and explored their first-level use in (Indian) University education in the context of developing countries. Besides using interactive animations and remotely-triggered experimental devices, a detailed mathematical simulator was implemented on a web-based software platform. In this study, we focused on the perceptions of technology adoption for a virtual neurophysiology laboratory as a new pedagogy tool for complementing college laboratory experience. The study analyses the effect of virtual labs on users assessing the relationship between cognitive, social and teaching presence. Combining feedback from learners and teachers, the study suggests enhanced motivation for students and improved teaching experience for instructors.
Diwakar, Shyam; Parasuram, Harilal; Medini, Chaitanya; Raman, Raghu; Nedungadi, Prema; Wiertelak, Eric; Srivastava, Sanjeeva; Achuthan, Krishnashree; Nair, Bipin
2014-01-01
Classroom-level neuroscience experiments vary from detailed protocols involving chemical, physiological and imaging techniques to computer-based modeling. The application of Information and Communication Technology (ICT) is revolutionizing the current laboratory scenario in terms of active learning especially for distance education cases. Virtual web-based labs are an asset to educational institutions confronting economic issues in maintaining equipment, facilities and other conditions needed for good laboratory practice. To enhance education, we developed virtual laboratories in neuroscience and explored their first-level use in (Indian) University education in the context of developing countries. Besides using interactive animations and remotely-triggered experimental devices, a detailed mathematical simulator was implemented on a web-based software platform. In this study, we focused on the perceptions of technology adoption for a virtual neurophysiology laboratory as a new pedagogy tool for complementing college laboratory experience. The study analyses the effect of virtual labs on users assessing the relationship between cognitive, social and teaching presence. Combining feedback from learners and teachers, the study suggests enhanced motivation for students and improved teaching experience for instructors. PMID:24693260
Brand, P; Havlicek, P; Steiners, M; Holzinger, K; Reisgen, U; Kraus, T; Gube, M
2013-01-01
Studies concerning welding fume-related adverse health effects in welders are hampered by the heterogeneity of workplace situations, resulting in complex and non-standardized exposure conditions. In order to carry out welding fume exposure studies under controlled and standardized conditions, the Aachen Workplace Simulation Laboratory was developed. This laboratory consists of an emission room, in which welding fume is produced, and an exposure room in which human subjects are exposed to these fumes. Both rooms are connected by a ventilation system which allows the welding fume concentration to be regulated. Particle mass concentration was measured with a TEOM microbalance and the particle number-size distribution using a Grimm SMPS device. In a study, which is the subject of this paper, it has been shown that welding fume concentration can easily be regulated between 1 and about 3 mg m(-3). The chosen concentration can be kept constant for more than 8 h. However, transport of the particles from the emission room into the exposure room leads to a change in particle size distribution, which is probably due to coagulation of the fraction of smallest particles. The Aachen Workplace Simulation Laboratory is suitable for controlled exposure studies with human subjects.
INTEGRATION OF PHOTOCATALYTIC OXIDATION WITH AIR STRIPPING OF CONTAMINATED AQUIFERS
Bench scale laboratory studies and pilot scale studies in a simulated field-test situation were performed to evaluate the integration of gas-solid ultaviolet (UV) photocatalytic oxidation (PCO) downstream if an air stripper unit as a technology for cost-effectively treating water...
Efficacy of a Virtual Teaching Assistant in an Open Laboratory Environment for Electric Circuits
ERIC Educational Resources Information Center
Saleheen, Firdous; Wang, Zicong; Picone, Joseph; Butz, Brian P.; Won, Chang-Hee
2018-01-01
In order to provide an on-demand, open electrical engineering laboratory, we developed an innovative software-based Virtual Open Laboratory Teaching Assistant (VOLTA). This web-based virtual assistant provides laboratory instructions, equipment usage videos, circuit simulation assistance, and hardware implementation diagnostics. VOLTA allows…
1987-04-01
Simulation Division (ERSD), Environmental Laboratory (EL), WES. Dr. Thomas L. Hart was Chief, APEG; Mr. Donald L. Robey was Chief, ERSD; and Dr. John...a technical committee to outline potential problems at the project site. b. Simulation of the Hartwell-Russell-Clarks Hill Lake system using physical...Heath (1979) reported the release of phosphate from two different classes of dissolved organic compounds. One of these classes had a high molecular
NASA Technical Reports Server (NTRS)
Baird, A. K.; Castro, A. J.; Clark, B. C.; Toulmin, P., III; Rose, H., Jr.; Keil, K.; Gooding, J. L.
1977-01-01
Ten samples of Mars regolith material (six on Viking Lander 1 and four on Viking Lander 2) have been delivered to the X ray fluorescence spectrometers as of March 31, 1977. An additional six samples at least are planned for acquisition in the remaining Extended Mission (to January 1979) for each lander. All samples acquired are Martian fines from the near surface (less than 6-cm depth) of the landing sites except the latest on Viking Lander 1, which is fine material from the bottom of a trench dug to a depth of 25 cm. Several attempts on each lander to acquire fresh rock material (in pebble sizes) for analysis have yielded only cemented surface crustal material (duricrust). Laboratory simulation and experimentation are required both for mission planning of sampling and for interpretation of data returned from Mars. This paper is concerned with the rationale for sample site selections, surface sampler operations, and the supportive laboratory studies needed to interpret X ray results from Mars.
Biomechanical testing simulation of a cadaver spine specimen: development and evaluation study.
Ahn, Hyung Soo; DiAngelo, Denis J
2007-05-15
This article describes a computer model of the cadaver cervical spine specimen and virtual biomechanical testing. To develop a graphics-oriented, multibody model of a cadaver cervical spine and to build a virtual laboratory simulator for the biomechanical testing using physics-based dynamic simulation techniques. Physics-based computer simulations apply the laws of physics to solid bodies with defined material properties. This technique can be used to create a virtual simulator for the biomechanical testing of a human cadaver spine. An accurate virtual model and simulation would complement tissue-based in vitro studies by providing a consistent test bed with minimal variability and by reducing cost. The geometry of cervical vertebrae was created from computed tomography images. Joints linking adjacent vertebrae were modeled as a triple-joint complex, comprised of intervertebral disc joints in the anterior region, 2 facet joints in the posterior region, and the surrounding ligament structure. A virtual laboratory simulation of an in vitro testing protocol was performed to evaluate the model responses during flexion, extension, and lateral bending. For kinematic evaluation, the rotation of motion segment unit, coupling behaviors, and 3-dimensional helical axes of motion were analyzed. The simulation results were in correlation with the findings of in vitro tests and published data. For kinetic evaluation, the forces of the intervertebral discs and facet joints of each segment were determined and visually animated. This methodology produced a realistic visualization of in vitro experiment, and allowed for the analyses of the kinematics and kinetics of the cadaver cervical spine. With graphical illustrations and animation features, this modeling technique has provided vivid and intuitive information.
Camp, Christopher L; Krych, Aaron J; Stuart, Michael J; Regnier, Terry D; Mills, Karen M; Turner, Norman S
2016-02-03
Cadaveric skills laboratories and virtual reality simulators are two common methods used outside of the operating room to improve residents' performance of knee arthroscopy. We are not aware of any head-to-head comparisons of the educational values of these two methodologies. The purpose of this prospective randomized trial was to assess the efficacy of these training methods, compare their rates of improvement, and provide economic value data to programs seeking to implement such technologies. Orthopaedic surgery residents were randomized to one of three groups: control, training on cadavera (cadaver group), and training with use of a simulator (simulator group). Residents completed pretest and posttest diagnostic knee arthroscopies on cadavera that were timed and video-recorded. Between the pretest and posttest, the control group performed no arthroscopy, the cadaver group performed four hours of practice on cadavera, and the simulator group trained for four hours on a simulator. All tests were scored in a blinded, randomized fashion using the validated Arthroscopy Surgical Skill Evaluation Tool (ASSET). The mean improvement in the ASSET score and in the time to complete the procedure were compared between the pretest and posttest and among the groups. Forty-five residents (fifteen per group) completed the study. The mean difference in the ASSET score from the pretest to the posttest was -0.40 (p = 0.776) in the control group, +4.27 (p = 0.002) in the cadaver group, and +1.92 (p = 0.096) in the simulator group (p = 0.015 for the comparison among the groups). The mean difference in the test-completion time (minutes:seconds) from the pretest to the posttest was 0:07 (p = 0.902) in the control group, 3:01 (p = 0.002) in the cadaver group, and 0:28 (p = 0.708) in the simulator group (p = 0.044 for the comparison among groups). Residents in the cadaver group improved their performance at a mean of 1.1 ASSET points per hour spent training whereas those in the simulator group improved 0.5 ASSET point per hour of training. Cadaveric skills laboratories improved residents' performance of knee arthroscopy compared with that of matched controls. Residents practicing on cadaveric specimens improved twice as fast as those utilizing a high-fidelity simulator; however, based on cost estimation specific to our institution, the simulator may be more cost-effective if it is used at least 300 hours per year. Additional study of this possibility is warranted. Copyright © 2016 by The Journal of Bone and Joint Surgery, Incorporated.
NASA Technical Reports Server (NTRS)
Steffes, Paul G.
1997-01-01
Radio absorptivity data for planetary atmospheres obtained from spacecraft radio occultation experiments and earth-based radio astronomical observations can be used to infer abundances of microwave absorbing constituents in those atmospheres, as long as reliable information regarding the microwave absorbing properties of potential constituents is available. The use of theoretically-derived microwave absorption properties for such atmospheric constituents, or using laboratory measurements of such properties under environmental conditions which are significantly different than those of the planetary atmosphere being studied, often leads to significant misinterpretation of available opacity data. Laboratory measurements completed under this grant (NAGW-533), have shown that the opacity from, SO2 under simulated Venus conditions is best described by a different lineshape than was previously used in theoretical predictions. The recognition of the need to make such laboratory measurements of simulated planetary atmospheres over a range of temperatures and pressures which correspond to the altitudes probed by both radio occultation experiments and radio astronomical observations, and over a range of frequencies which correspond to those used in both radio occultation experiments and radio astronomical observations, has led to the development of a facility at Georgia Tech which is capable of making such measurements. It has been the goal of this investigation to conduct such measurements and to apply the results to a wide range of planetary observations, both spacecraft and earth-based, in order to determine the identity and abundance profiles of constituents in those planetary atmospheres.
Space Electric Research Test in the Electric Propulsion Laboratory
1964-06-21
Technicians prepare the Space Electric Research Test (SERT-I) payload for a test in Tank Number 5 of the Electric Propulsion Laboratory at the National Aeronautics and Space Administration (NASA) Lewis Research Center. Lewis researchers had been studying different methods of electric rocket propulsion since the mid-1950s. Harold Kaufman created the first successful engine, the electron bombardment ion engine, in the early 1960s. These electric engines created and accelerated small particles of propellant material to high exhaust velocities. Electric engines have a very small amount of thrust, but once lofted into orbit by workhorse chemical rockets, they are capable of small, continuous thrust for periods up to several years. The electron bombardment thruster operated at a 90-percent efficiency during testing in the Electric Propulsion Laboratory. The package was rapidly rotated in a vacuum to simulate its behavior in space. The SERT-I mission, launched from Wallops Island, Virginia, was the first flight test of Kaufman’s ion engine. SERT-I had one cesium engine and one mercury engine. The suborbital flight was only 50 minutes in duration but proved that the ion engine could operate in space. The Electric Propulsion Laboratory included two large space simulation chambers, one of which is seen here. Each uses twenty 2.6-foot diameter diffusion pumps, blowers, and roughing pumps to remove the air inside the tank to create the thin atmosphere. A helium refrigeration system simulates the cold temperatures of space.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thornton, Joel
2016-05-01
The Thornton Laboratory participated in the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility’s Biogenic Aerosol Effects on Clouds and Climate (BAECC) campaign in Finland by deploying our mass spectrometer. We then participated in environmental simulation chamber studies at Pacific Northwest National Laboratory (PNNL). Thereafter, we analyzed the results as demonstrated in the several presentations and publications. The field campaign and initial environmental chamber studies are described below.
Laboratory Spectroscopy of Large Carbon Molecules and Ions in Support of Space Missions
NASA Technical Reports Server (NTRS)
Salana, Farid; Tan, X.; Cami, J.; Remy, J.
2006-01-01
One of the major objectives of Laboratory Astrophysics is the optimization of data return from space missions by measuring spectra of atomic and molecular species in laboratory environments that mimic interstellar conditions (WhitePaper (2002, 2006)). Among interstellar species, PAHs are an important and ubiquitous component of carbon-bearing materials that represents a particularly difficult challenge for gas-phase laboratory studies. We present the absorption spectra of jet-cooled neutral and ionized PAHs and discuss the implications for astrophysics. The harsh physical conditions of the interstellar medium have been simulated in the laboratory. We are now, for the first time, in the position to directly compare laboratory spectra of PAHs and carbon nanoparticles with astronomical observations. This new phase offers tremendous opportunities for the data analysis of current and upcoming space missions geared toward the detection of large aromatic systems (HST/COS, FUSE, JWST, Spitzer).
Kenny, Michael T.; Sabel, Fred L.
1968-01-01
Andersen air samplers were used to determine the particle size distribution of Serratia marcescens aerosols created during several common laboratory procedures and simulated laboratory accidents. Over 1,600 viable particles per cubic foot of air sampled were aerosolized during blending operations. More than 98% of these particles were less than 5 μ in size. In contrast, 80% of the viable particles aerosolized by handling lyophilized cultures were larger than 5 μ. Harvesting infected eggs, sonic treatment, centrifugation, mixing cultures, and dropping infectious material produced aerosols composed primarily of particles in the 1.0- to 7.5-μ size range. Images Fig. 1 PMID:4877498
Pilot GPS LORAN Receiver Programming Performance A Laboratory Evaluation
DOT National Transportation Integrated Search
1994-02-01
This study was designed to explore GPS/LORAN receiver programming performance under : simulated flight conditions. The programming task consisted of entering, editing, and : verifying a four-waypoint flight plan. The task demands were manipulated by ...
Energetic Materials Laboratory
2015-04-30
regolith simulants mixed with magnesium, supported by NASA. It has also been used for studies on combustion synthesis of magnesium silicide , a...ammonium dinitramide based monopropellant. The laser flash apparatus has been used for thermal diffusivities measurements for magnesium silicide and
Lees, Monica N.; Cosman, Joshua D.; Lee, John D.; Rizzo, Matthew; Fricke, Nicola
2012-01-01
Neuroergonomics provides a multidisciplinary translational approach that merges elements of neuroscience, human factors, cognitive psychology, and ergonomics to study brain structure and function in everyday environments. Driving safety, particularly that of older drivers with cognitive impairments, is a fruitful application domain for neuroergonomics. Driving makes demands on multiple cognitive processes that are often studied in isolation and so presents a useful challenge in generalizing findings from controlled laboratory tasks to predict safety outcomes. Neurology and the cognitive sciences help explain the mechanisms of cognitive breakdowns that undermine driving safety. Ergonomics complements this explanation with the tools for systematically exploring the various layers of complexity that define the activity of driving. A variety of tools, such as part task simulators, driving simulators, and instrumented vehicles provide a window into cognition in the natural settings needed to assess the generalizability of laboratory findings and can provide an array of potential interventions to increase safety. PMID:21291157
NASA Astrophysics Data System (ADS)
Vogler, D.; Settgast, R. R.; Annavarapu, C.; Madonna, C.; Bayer, P.; Amann, F.
2018-02-01
In this work, we present the application of a fully coupled hydro-mechanical method to investigate the effect of fracture heterogeneity on fluid flow through fractures at the laboratory scale. Experimental and numerical studies of fracture closure behavior in the presence of heterogeneous mechanical and hydraulic properties are presented. We compare the results of two sets of laboratory experiments on granodiorite specimens against numerical simulations in order to investigate the mechanical fracture closure and the hydro-mechanical effects, respectively. The model captures fracture closure behavior and predicts a nonlinear increase in fluid injection pressure with loading. Results from this study indicate that the heterogeneous aperture distributions measured for experiment specimens can be used as model input for a local cubic law model in a heterogeneous fracture to capture fracture closure behavior and corresponding fluid pressure response.
Cardiovascular system simulation in biomedical engineering education.
NASA Technical Reports Server (NTRS)
Rideout, V. C.
1972-01-01
Use of complex cardiovascular system models, in conjunction with a large hybrid computer, in biomedical engineering courses. A cardiovascular blood pressure-flow model, driving a compartment model for the study of dye transport, was set up on the computer for use as a laboratory exercise by students who did not have the computer experience or skill to be able to easily set up such a simulation involving some 27 differential equations running at 'real time' rate. The students were given detailed instructions regarding the model, and were then able to study effects such as those due to septal and valve defects upon the pressure, flow, and dye dilution curves. The success of this experiment in the use of involved models in engineering courses was such that it seems that this type of laboratory exercise might be considered for use in physiology courses as an adjunct to animal experiments.
McCabe, G.J.; Dettinger, M.D.
1995-01-01
General circulation model (GCM) simulations of atmospheric circulation are more reliable than GCM simulations of temperature and precipitation. In this study, temporal correlations between 700 hPa height anomalies simulated winter precipitation at eight locations in the conterminous United States are compared with corresponding correlations in observations. The objectives are to 1) characterize the relations between atmospheric circulation and winter precipitation simulated by the GFDL, GCM for selected locations in the conterminous USA, ii) determine whether these relations are similar to those found in observations of the actual climate system, and iii) determine if GFDL-simulated precipitation is forced by the same circulation patterns as in the real atmosphere. -from Authors
Numerically robust and efficient nonlocal electron transport in 2D DRACO simulations
NASA Astrophysics Data System (ADS)
Cao, Duc; Chenhall, Jeff; Moses, Greg; Delettrez, Jacques; Collins, Tim
2013-10-01
An improved implicit algorithm based on Schurtz, Nicolai and Busquet (SNB) algorithm for nonlocal electron transport is presented. Validation with direct drive shock timing experiments and verification with the Goncharov nonlocal model in 1D LILAC simulations demonstrate the viability of this efficient algorithm for producing 2D lagrangian radiation hydrodynamics direct drive simulations. Additionally, simulations provide strong incentive to further modify key parameters within the SNB theory, namely the ``mean free path.'' An example 2D polar drive simulation to study 2D effects of the nonlocal flux as well as mean free path modifications will also be presented. This research was supported by the University of Rochester Laboratory for Laser Energetics.
Numerical modeling of the fracture process in a three-unit all-ceramic fixed partial denture.
Kou, Wen; Kou, Shaoquan; Liu, Hongyuan; Sjögren, Göran
2007-08-01
The main objectives were to examine the fracture mechanism and process of a ceramic fixed partial denture (FPD) framework under simulated mechanical loading using a recently developed numerical modeling code, the R-T(2D) code, and also to evaluate the suitability of R-T(2D) code as a tool for this purpose. Using the recently developed R-T(2D) code the fracture mechanism and process of a 3U yttria-tetragonal zirconia polycrystal ceramic (Y-TZP) FPD framework was simulated under static loading. In addition, the fracture pattern obtained using the numerical simulation was compared with the fracture pattern obtained in a previous laboratory test. The result revealed that the framework fracture pattern obtained using the numerical simulation agreed with that observed in a previous laboratory test. Quasi-photoelastic stress fringe pattern and acoustic emission showed that the fracture mechanism was tensile failure and that the crack started at the lower boundary of the framework. The fracture process could be followed both in step-by-step and step-in-step. Based on the findings in the current study, the R-T(2D) code seems suitable for use as a complement to other tests and clinical observations in studying stress distribution, fracture mechanism and fracture processes in ceramic FPD frameworks.
Jongen, S; Vuurman, E F P M; Ramaekers, J G; Vermeeren, A
2016-04-01
Laboratory tests assessing driving related skills can be useful as initial screening tools to assess potential drug induced impairment as part of a standardized behavioural assessment. Unfortunately, consensus about which laboratory tests should be included to reliably assess drug induced impairment has not yet been reached. The aim of the present review was to evaluate the sensitivity of laboratory tests to the dose dependent effects of alcohol, as a benchmark, on performance parameters. In total, 179 experimental studies were included. Results show that a cued go/no-go task and a divided attention test with primary tracking and secondary visual search were consistently sensitive to the impairing effects at medium and high blood alcohol concentrations. Driving performance assessed in a simulator was less sensitive to the effects of alcohol as compared to naturalistic, on-the-road driving. In conclusion, replicating results of several potentially useful tests and their predictive validity of actual driving impairment should deserve further research. In addition, driving simulators should be validated and compared head to head to naturalistic driving in order to increase construct validity. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Radiation Testing at Sandia National Laboratories: Sandia – JPL Collaboration for Europa Lander
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hattar, Khalid Mikhiel; Olszewska-Wasiolek, Maryla Aleksandra
Sandia National Laboratories (SNL) is assisting Jet Propulsion Laboratory in undertaking feasibility studies and performance assessments for the Planetary Protection aspect of the Europa Lander mission. The specific areas of interest for this project are described by task number. This white paper presents the evaluation results for Task 2, Radiation Testing, which was stated as follows: Survey SNL facilities and capabilities for simulating the Europan radiation environment and assess suitability for: A. Testing batteries, electronics, and other component and subsystems B. Exposing biological organisms to assess their survivability metrics. The radiation environment the Europa Lander will encounter on route andmore » in orbit upon arrival at its destination consists primarily of charged particles, energetic protons and electrons with the energies up to 1 GeV. The charged particle environments can be simulated using the accelerators at the Ion Beam Laboratory. The Gamma Irradiation Facility and its annex, the Low Dose Rate Irradiation Facility, offer irradiations using Co-60 gamma sources (1.17 and 1.33 MeV), as well as Cs-137 gamma (0.661 MeV) AmBe neutron (0-10 MeV) sources.« less
NASA Ames’ COSmIC Laboratory Astrophysics Facility: Recent Results and Progress
NASA Astrophysics Data System (ADS)
Salama, Farid; Sciamma-O'Brien, Ella; Bejaoui, Salma
2018-06-01
The COSmIC facility was developed at NASA Ames to study interstellar, circumstellar and planetary analogs in the laboratory [1, 2]. COSmIC stands for “Cosmic Simulation Chamber” and is dedicated to the study of molecules, ions and nanoparticles under the low temperature and high vacuum conditions that are required to simulate space environments. COSmIC integrates a variety of instruments that allow generating; processing and monitoring simulated space conditions in the laboratory. It is composed of a Pulsed Discharge Nozzle expansion that generates a plasma in a free supersonic jet expansion coupled to high-sensitivity, complementary in situ diagnostic tools, used for the detection and characterization of the species present in the expansion: a Cavity Ring Down Spectroscopy (CRDS) and fluorescence spectroscopy systems for photonic detection, and a Reflectron Time-Of-Flight Mass Spectrometer (ReTOF-MS) for mass detection [3, 4].Recent advances achieved in laboratory astrophysics using COSmIC will be presented, in particular in the domain of the diffuse interstellar bands (DIBs) [5, 6] and the monitoring, in the laboratory, of the formation of dust grains and aerosols from their gas-phase molecular precursors in environments as varied as circumstellar outflows [7] and planetary atmospheres [8, 9, 10]. Plans for future laboratory experiments on cosmic molecules and grains in the growing field of laboratory astrophysics (NIR-MIR CRDS, Laser Induced Fluorescence spectra of cosmic molecule analogs and the laser induced incandescence spectra of cosmic grain analogs) will also be addressed as well as the implications for astronomy.References: [1] Salama F., Proceed. IAU S251, Kwok & Sandford eds. CUP, 4, 357 (2008).[2] Salama F., et al., Proceed. IAU S332, Y. Aikawa, M. Cunningham, T. Millar, eds., CUP (2018)[3] Biennier L., et al., J. Chem. Phys., 118, 7863 (2003)[4] Ricketts C. et al. IJMS, 300, 26 (2011)[5] Salama F., et al., ApJ., 728, 154 (2011)[6] EDIBLES consortium, A&A 606, A76 (2017)[7] Contreras, C., Salama, F., ApJ. Suppl. Ser., 208, 6 (2013)[8] Sciamma-O'Brien E., Ricketts C., Salama F. Icarus, 243, 325 (2014)[9] Sciamma-O'Brien E., Upton K.T., Salama F. Icarus, Icarus, 289, 214 (2017)[10] Raymond A.W., et al.. ApJ., 853, 107 (2018)The authors acknowledge NASA SMD/APRA and SSW programs.
Numerical sedimentation particle-size analysis using the Discrete Element Method
NASA Astrophysics Data System (ADS)
Bravo, R.; Pérez-Aparicio, J. L.; Gómez-Hernández, J. J.
2015-12-01
Sedimentation tests are widely used to determine the particle size distribution of a granular sample. In this work, the Discrete Element Method interacts with the simulation of flow using the well known one-way-coupling method, a computationally affordable approach for the time-consuming numerical simulation of the hydrometer, buoyancy and pipette sedimentation tests. These tests are used in the laboratory to determine the particle-size distribution of fine-grained aggregates. Five samples with different particle-size distributions are modeled by about six million rigid spheres projected on two-dimensions, with diameters ranging from 2.5 ×10-6 m to 70 ×10-6 m, forming a water suspension in a sedimentation cylinder. DEM simulates the particle's movement considering laminar flow interactions of buoyant, drag and lubrication forces. The simulation provides the temporal/spatial distributions of densities and concentrations of the suspension. The numerical simulations cannot replace the laboratory tests since they need the final granulometry as initial data, but, as the results show, these simulations can identify the strong and weak points of each method and eventually recommend useful variations and draw conclusions on their validity, aspects very difficult to achieve in the laboratory.
ERIC Educational Resources Information Center
Wee, Loo Kang; Ning, Hwee Tiang
2014-01-01
This paper presents the customization of Easy Java Simulation models, used with actual laboratory instruments, to create active experiential learning for measurements. The laboratory instruments are the vernier caliper and the micrometer. Three computer model design ideas that complement real equipment are discussed. These ideas involve (1) a…
Use of a PhET Interactive Simulation in General Chemistry Laboratory: Models of the Hydrogen Atom
ERIC Educational Resources Information Center
Clark, Ted M.; Chamberlain, Julia M.
2014-01-01
An activity supporting the PhET interactive simulation, Models of the Hydrogen Atom, has been designed and used in the laboratory portion of a general chemistry course. This article describes the framework used to successfully accomplish implementation on a large scale. The activity guides students through a comparison and analysis of the six…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Le Blanc, Katya Lee; Spielman, Zachary Alexander; Rice, Brandon Charles
2016-04-01
This report describes the installation of two advanced control room technologies, an advanced alarm system and a computerized procedure system, into the Human Systems Simulation Laboratory (HSSL). Installation of these technologies enables future phases of this research by providing a platform to systematically evaluate the effect of these technologies on operator and plant performance.
Lepo, J.E., C. R. Cripe, J.L. Kavanaugh, S. Zhang and G.P. Norton. 2003. Effect of Amount of Crude Oil on Extent of Its Biodegradation in Open Water- and Sandy Beach-Laboratory Simulations. Environ. Technol. 24(10):1291-1302. (ERL,GB 1109).
We examined the biodegradation ...
The objective of these laboratory experiments was to determine the role nitrate plays in enhancing the biodegradation of fuel contaminated groundwater. Column studies were conducted to simulate the nitrate field demonstration project carried out earlier at Traverse City, MI so a...
DOT National Transportation Integrated Search
2007-12-01
Two Stormwater Treatment Systems were instrumented and monitored in the field for one : year to evaluate their effectiveness at contaminant removal. The Vortechs and the V2b1TM : were both installed by the NYS Department of Transportation at locati...
ATMOSPHERIC RELEASES FROM STANDARDIZED NUCLEAR POWER PLANTS: A WIND TUNNEL STUDY
Laboratory experiments were conducted to simulate radiopollutant effluents released to the atmosphere from two standard design nuclear power plants. The main objective of the study was to compare the dispersion in the wake of the standardized nuclear power plants with that in a s...
Crashworthiness simulation of composite automotive structures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Botkin, M E; Johnson, N L; Simunovic, S
1998-06-01
In 1990 the Automotive Composites Consortium (ACC) began the investigation of crash worthiness simulation methods for composite materials. A contract was given to Livermore Software Technology Corporation (LSTC) to implement a new damage model in LS-DYNA3D TM specifically for composite structures. This model is in LS-DYNA3D TM and is in use by the ACC partners. In 1994 USCAR, a partnership of American auto companies, entered into a partnership called SCAAP (Super Computing Automotive Applications Partnership) for the express purpose of working with the National Labs on computational oriented research. A CRADA (Cooperative Research and Development Agreement) was signed with Lawrencemore » Livermore National Laboratory, Oak Ridge National Laboratory, Sandia National Laboratory, Argonne National Laboratory, and Los Alamos National Laboratory to work in three distinctly different technical areas, one of which was composites material modeling for crash worthiness. Each Laboratory was assigned a specific modeling task. The ACC was responsible for the technical direction of the composites project and provided all test data for code verification. All new models were to be implemented in DYNA3D and periodically distributed to all partners for testing. Several new models have been developed and implemented. Excellent agreement has been shown between tube crush simulation and experiments.« less
ERIC Educational Resources Information Center
Oser, Rachel; Fraser, Barry J.
2015-01-01
As society becomes increasingly global and experiential, research suggests that students can benefit from alternative learning environments that extend beyond the classroom. In providing students with laboratory experiences that otherwise would not be possible in high-school settings, virtual laboratories can simulate real laboratories and…
NASA Technical Reports Server (NTRS)
Steffes, Paul G.
1988-01-01
In the first half of this grant year, laboratory measurements were conducted on the millimeter-wave properties of atmospheric gases under simulated conditions for the outer planet. Significant improvements in the current system have made it possible to accurately characterize the opacity from gaseous NH3 at longer millimeter wavelengths (7 to 10 mm) under simulated Jovian conditions. In the second half of the grant year, it is hoped to extend such measurements to even shorter millimeter-wavelengths. Further analysis and application of the laboratory results to microwave and millimeter-wave absorption data for the outer planets, such as results from Voyager Radio Occultation experiments and earth-based radio astronomical observations will be continued. The analysis of available multispectral microwave opacity data from Venus, including data from the most recent radio astronomical ovservations in the 1.3 to 3.6 cm wavelength range and newly obtained Pioneer-Venus Radio Occulatation measurements at 13 cm, using the laboratory measurements as an interpretative tool will be pursued.
Sumner, Andrew J; Woo, Joseph L; McNeill, V Faye
2014-10-21
The reactive uptake of glyoxal by atmospheric aerosols is believed to be a significant source of secondary organic aerosol (SOA). Several recent laboratory studies have been performed with the goal of characterizing this process, but questions remain regarding the effects of photochemistry on SOA growth. We applied GAMMA (McNeill et al. Environ. Sci. Technol. 2012, 46, 8075-8081), a photochemical box model with coupled gas-phase and detailed aqueous aerosol-phase chemistry, to simulate aerosol chamber studies of SOA formation by the uptake of glyoxal by wet aerosol under dark and irradiated conditions (Kroll et al. J. Geophys. Res. 2005, 110 (D23), 1-10; Volkamer et al. Atmos. Chem. Phys. 2009, 9, 1907-1928; Galloway et al. Atmos. Chem. Phys. 2009, 9, 3331- 306 3345 and Geophys. Res. Lett. 2011, 38, L17811). We find close agreement between simulated SOA growth and the results of experiments conducted under dark conditions using values of the effective Henry's Law constant of 1.3-5.5 × 10(7) M atm(-1). While irradiated conditions led to the production of some organic acids, organosulfates, and other oxidation products via well-established photochemical mechanisms, these additional product species contribute negligible aerosol mass compared to the dark uptake of glyoxal. Simulated results for irradiated experiments therefore fell short of the reported SOA mass yield by up to 92%. This suggests a significant light-dependent SOA formation mechanism that is not currently accounted for by known bulk photochemistry, consistent with recent laboratory observations of SOA production via photosensitizer chemistry.
NASA Astrophysics Data System (ADS)
Wosnik, Martin; Bachant, Peter
2016-11-01
Cross-flow turbines show potential in marine hydrokinetic (MHK) applications. A research focus is on accurately predicting device performance and wake evolution to improve turbine array layouts for maximizing overall power output, i.e., minimizing wake interference, or taking advantage of constructive wake interaction. Experiments were carried with large laboratory-scale cross-flow turbines D O (1 m) using a turbine test bed in a large cross-section tow tank, designed to achieve sufficiently high Reynolds numbers for the results to be Reynolds number independent with respect to turbine performance and wake statistics, such that they can be reliably extrapolated to full scale and used for model validation. Several turbines of varying solidity were employed, including the UNH Reference Vertical Axis Turbine (RVAT) and a 1:6 scale model of the DOE-Sandia Reference Model 2 (RM2) turbine. To improve parameterization in array simulations, an actuator line model (ALM) was developed to provide a computationally feasible method for simulating full turbine arrays inside Navier-Stokes models. Results are presented for the simulation of performance and wake dynamics of cross-flow turbines and compared with experiments and body-fitted mesh, blade-resolving CFD. Supported by NSF-CBET Grant 1150797, Sandia National Laboratories.
Simulating flow in karst aquifers at laboratory and sub-regional scales using MODFLOW-CFP
NASA Astrophysics Data System (ADS)
Gallegos, Josue Jacob; Hu, Bill X.; Davis, Hal
2013-12-01
Groundwater flow in a well-developed karst aquifer dominantly occurs through bedding planes, fractures, conduits, and caves created by and/or enlarged by dissolution. Conventional groundwater modeling methods assume that groundwater flow is described by Darcian principles where primary porosity (i.e. matrix porosity) and laminar flow are dominant. However, in well-developed karst aquifers, the assumption of Darcian flow can be questionable. While Darcian flow generally occurs in the matrix portion of the karst aquifer, flow through conduits can be non-laminar where the relation between specific discharge and hydraulic gradient is non-linear. MODFLOW-CFP is a relatively new modeling program that accounts for non-laminar and laminar flow in pipes, like karst caves, within an aquifer. In this study, results from MODFLOW-CFP are compared to those from MODFLOW-2000/2005, a numerical code based on Darcy's law, to evaluate the accuracy that CFP can achieve when modeling flows in karst aquifers at laboratory and sub-regional (Woodville Karst Plain, Florida, USA) scales. In comparison with laboratory experiments, simulation results by MODFLOW-CFP are more accurate than MODFLOW 2005. At the sub-regional scale, MODFLOW-CFP was more accurate than MODFLOW-2000 for simulating field measurements of peak flow at one spring and total discharges at two springs for an observed storm event.
Teaching Engineering Design in a Laboratory Setting
ERIC Educational Resources Information Center
Hummon, Norman P.; Bullen, A. G. R.
1974-01-01
Discusses the establishment of an environmental systems laboratory at the University of Pittsburgh with the support of the Sloan Foundation. Indicates that the "real world" can be brought into the laboratory by simulating on computers, software systems, and data bases. (CC)
The Viability of Distance Education Science Laboratories.
ERIC Educational Resources Information Center
Forinash, Kyle; Wisman, Raymond
2001-01-01
Discusses the effectiveness of offering science laboratories via distance education. Explains current delivery technologies, including computer simulations, videos, and laboratory kits sent to students; pros and cons of distance labs; the use of spreadsheets; and possibilities for new science education models. (LRW)
Laboratory simulation of the astrophysical burst processes in non-uniform magnetised media
NASA Astrophysics Data System (ADS)
Antonov, V. M.; Zakharov, Yu. P.; Orishich, A. M.; Ponomarenko, A. G.; Posukh, V. G.; Snytnikov, V. N.; Stoyanovsky, V. O.
1990-08-01
Under various astrophysical conditions the dynamics of nonstationary burst processes with mass and energy release may be defined by the inhomogeneity of the surrounding medium. In the presence of external magnetic field such a problem in general case becomes a three dimensional one and very complicated both from the observable and theoretical point of view (including the computer simulation method). The application of the laboratory simulation methods in such kinds of problems therefore seems to be rather promising and is demonstrated, mainly on the example of peculiar supernova.
An innovative exercise method to simulate orbital EVA work - Applications to PLSS automatic controls
NASA Technical Reports Server (NTRS)
Lantz, Renee; Vykukal, H.; Webbon, Bruce
1987-01-01
An exercise method has been proposed which may satisfy the current need for a laboratory simulation representative of muscular, cardiovascular, respiratory, and thermoregulatory responses to work during orbital extravehicular activity (EVA). The simulation incorporates arm crank ergometry with a unique body support mechanism that allows all body position stabilization forces to be reacted at the feet. By instituting this exercise method in laboratory experimentation, an advanced portable life support system (PLSS) thermoregulatory control system can be designed to more accurately reflect the specific work requirements of orbital EVA.
Simulations of a Molecular Cloud experiment using CRASH
NASA Astrophysics Data System (ADS)
Trantham, Matthew; Keiter, Paul; Vandervort, Robert; Drake, R. Paul; Shvarts, Dov
2017-10-01
Recent laboratory experiments explore molecular cloud radiation hydrodynamics. The experiment irradiates a gold foil with a laser producing x-rays to drive the implosion or explosion of a foam ball. The CRASH code, an Eulerian code with block-adaptive mesh refinement, multigroup diffusive radiation transport, and electron heat conduction developed at the University of Michigan to design and analyze high-energy-density experiments, is used to perform a parameter search in order to identify optically thick, optically thin and transition regimes suitable for these experiments. Specific design issues addressed by the simulations are the x-ray drive temperature, foam density, distance from the x-ray source to the ball, as well as other complicating issues such as the positioning of the stalk holding the foam ball. We present the results of this study and show ways the simulations helped improve the quality of the experiment. This work is funded by the LLNL under subcontract B614207 and NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, Grant Number DE-NA0002956.
NASA Astrophysics Data System (ADS)
Hall, C. C.; Biedron, S. G.; Edelen, A. L.; Milton, S. V.; Benson, S.; Douglas, D.; Li, R.; Tennant, C. D.; Carlsten, B. E.
2015-03-01
In an experiment conducted on the Jefferson Laboratory IR free-electron laser driver, the effects of coherent synchrotron radiation (CSR) on beam quality were studied. The primary goal of this work was to explore CSR output and effect on the beam with variation of the bunch compression in the IR recirculator. Here we examine the impact of CSR on the average energy loss as a function of bunch compression as well as the impact of CSR on the energy spectrum of the bunch. Simulation of beam dynamics in the machine, including the one-dimensional CSR model, shows very good agreement with the measured effect of CSR on the average energy loss as a function of compression. Finally, a well-defined structure is observed in the energy spectrum with a feature in the spectrum that varies as a function of the compression. This effect is examined in simulations, as well, and a simple explanation for the variation is proposed.
Çelik, Yasemin; Ceylantekin, Yeşim; Kiliç, İbrahim
2017-01-01
Objective: The aim of this study is to detect the overall evaluation of nursing students toward simulation markets throughout the practice education and to reveal their learning styles in relation to certain individual features. Materials and Methods: The data were collected via questionnaires including students’ evaluation toward simulation markets and “Kolb learning styles inventory.” Participants included 103 male and female nursing students in Turkey. For the analysis, percentage, means, standard deviation, t-test, and ANOVA were utilized. Results: 71% of the students stated that the laboratory was suitable for the skill education but 53.4% uttered the duration of the practice was not enough. Students were found to have different learning styles (28.2% assimilating, 27.2% convergent, 26.2% accommodating, and 18.4% divergent). Conclusion: The results demonstrated that the duration of the laboratory practice and the number of the markets should be increased during the education of students with different learning styles. PMID:28293150
Çelik, Yasemin; Ceylantekin, Yeşim; Kiliç, İbrahim
2017-01-01
Objective: The aim of this study is to detect the overall evaluation of nursing students toward simulation makets throughout the practice education and to reveal their learning styles in relation to certain individual features. Materials and Methods: The data were collected via questionnaires including students’ evaluation toward simulation makets and “Kolb learning styles inventory.” Participants included 103 male and female nursing students in Turkey. For the analysis, percentage, means, standard deviation, t-test, and ANOVA were utilized. Results: 71% of the students stated that the laboratory was suitable for the skill education but 53.4% uttered the duration of the practice was not enough. Students were found to have different learning styles (28.2% assimilating, 27.2% convergent, 26.2% accommodating, and 18.4% divergent). Conclusion: The results demonstrated that the duration of the laboratory practice and the number of the makets should be increased during the education of students with different learning styles. PMID:28936157
Measurements and Computations of Flow in an Urban Street System
NASA Astrophysics Data System (ADS)
Castro, Ian P.; Xie, Zheng-Tong; Fuka, V.; Robins, Alan G.; Carpentieri, M.; Hayden, P.; Hertwig, D.; Coceal, O.
2017-02-01
We present results from laboratory and computational experiments on the turbulent flow over an array of rectangular blocks modelling a typical, asymmetric urban canopy at various orientations to the approach flow. The work forms part of a larger study on dispersion within such arrays (project DIPLOS) and concentrates on the nature of the mean flow and turbulence fields within the canopy region, recognising that unless the flow field is adequately represented in computational models there is no reason to expect realistic simulations of the nature of the dispersion of pollutants emitted within the canopy. Comparisons between the experimental data and those obtained from both large-eddy simulation (LES) and direct numerical simulation (DNS) are shown and it is concluded that careful use of LES can produce generally excellent agreement with laboratory and DNS results, lending further confidence in the use of LES for such situations. Various crucial issues are discussed and advice offered to both experimentalists and those seeking to compute canopy flows with turbulence resolving models.
Hall, C C.; Biedron, S G.; Edelen, A L.; ...
2015-03-09
In an experiment conducted on the Jefferson Laboratory IR free-electron laser driver, the effects of coherent synchrotron radiation (CSR) on beam quality were studied. The primary goal of this work was to explore CSR output and effect on the beam with variation of the bunch compression in the IR recirculator. Here we examine the impact of CSR on the average energy loss as a function of bunch compression as well as the impact of CSR on the energy spectrum of the bunch. Simulation of beam dynamics in the machine, including the one-dimensional CSR model, shows very good agreement with themore » measured effect of CSR on the average energy loss as a function of compression. Finally, a well-defined structure is observed in the energy spectrum with a feature in the spectrum that varies as a function of the compression. This effect is examined in simulations, as well, and a simple explanation for the variation is proposed.« less
Tzeferacos, Petros; Rigby, A.; Bott, A.; ...
2017-03-22
The universe is permeated by magnetic fields, with strengths ranging from a femtogauss in the voids between the filaments of galaxy clusters to several teragauss in black holes and neutron stars. The standard model behind cosmological magnetic fields is the nonlinear amplification of seed fields via turbulent dynamo to the values observed. We have conceived experiments that aim to demonstrate and study the turbulent dynamo mechanism in the laboratory. Here, we describe the design of these experiments through simulation campaigns using FLASH, a highly capable radiation magnetohydrodynamics code that we have developed, and large-scale three-dimensional simulations on the Mira supercomputermore » at the Argonne National Laboratory. The simulation results indicate that the experimental platform may be capable of reaching a turbulent plasma state and determining the dynamo amplification. As a result, we validate and compare our numerical results with a small subset of experimental data using synthetic diagnostics.« less
Center For Advanced Energy Studies Overview
Blackman, Harold; Curnutt, Byron; Harker, Caitlin; Hamilton, Melinda; Butt, Darryl; Imel, George; Tokuhiro, Akira; Harris, Jason; Hill, David
2017-12-09
A collaboration between Idaho National Laboratory, Boise State University, Idaho State University and the University of Idaho. Conducts research in nuclear energy, advanced materials, carbon management, bioenergy, energy policy, modeling and simulation, and energy efficiency. Educates next generation of energy workforce.
CPRIT/Johnson Space Center, September, 2011 (Cancer Prevention and Research Institute of Texas)
NASA Technical Reports Server (NTRS)
Davis, Jeffrey; Lane, Helen; Baker, Tracey; Cucinotta, Francis; Wu, Honglu
2011-01-01
JSC researchers study carcinogenesis, cancer prevention and treatment along with epidemiological (primarily retrospective and longitudinal) studies, modeling, and interactions with the environment such as radiation, nutritional, and endocrine changes related to space flight along with behaviors such as smoking. Cancer research is a major focus for human space flight due to the exposure to space radiation which consists of particles of varying charges and energies, and secondary neutrons. The JSC laboratories collaborate with investigators from the U.S. as well as our European and Japanese partners. We use accelerator facilities at the Brookhaven National Laboratory, Loma Linda University and Los Alamos National Laboratory that generate high energy charged particles and neutrons to simulate cosmic radiation and solar particle events. The research using cultured cells and animals concentrates on damage and repair from the level of DNA to organ tissues, due to exposure to simulated space radiation exposure, that contribute to the induction of leukemia and solid tumors in most major tissues such as lung, colon, liver and breast. The goal of the research is to develop a mathematical model that can predict cancer morbidity and mortality risks with sufficient accuracy for a given space mission.
Light field and water clarity simulation of natural environments in laboratory conditions
NASA Astrophysics Data System (ADS)
Pe'eri, Shachak; Shwaery, Glenn
2012-06-01
Simulation of natural oceanic conditions in a laboratory setting is a challenging task, especially when that environment can be miles away. We present an attempt to replicate the solar radiation expected at different latitudes with varying water clarity conditions up to 30 m in depth using a 2.5 m deep engineering tank at the University of New Hampshire. The goals of the study were: 1) to configure an underwater light source that produced an irradiance spectrum similar to natural daylight with the sun at zenith and at 60° under clear atmospheric conditions, and 2) to monitor water clarity as a function of depth. Irradiance was measured using a spectra-radiometer with a cosine receiver to analyze the output spectrum of submersed lamps as a function of distance. In addition, an underwater reflection method was developed to measure the diffuse attenuation coefficient in real time. Two water clarity types were characterized, clear waters representing deep, open-ocean conditions, and murky waters representing littoral environments. Results showed good correlation between the irradiance measured at 400 nm to 600 nm and the natural daylight spectrum at 3 m from the light source. This can be considered the water surface conditions reference. Using these methodologies in a controlled laboratory setting, we are able to replicate illumination and water conditions to study the physical, chemical and biological processes on natural and man-made objects and/or systems in simulated, varied geographic locations and environments.
Laboratory simulation of Hg0 emissions from a snowpack.
Dommergue, Aurélien; Bahlmann, Enno; Ebinghaus, Ralf; Ferrari, Christophe; Boutron, Claude
2007-05-01
Snow surfaces play an important role in the biogeochemical cycle of mercury in high-latitude regions. Snowpacks act both as sources and sinks for gaseous compounds. Surprisingly, the roles of each environmental parameter that can govern the air-surface exchange over snow are not well understood owing to the lack of systematic studies. A laboratory system called the laboratory flux measurement system was used to study the emission of gaseous elemental mercury from a natural snowpack under controlled conditions. The first results from three snowpacks originating from alpine, urban and polar areas are presented. Consistent with observations in the field, we were able to reproduce gaseous mercury emissions and showed that they are mainly driven by solar radiation and especially UV-B radiation. From these laboratory experiments, we derived kinetic constants which show that divalent mercury can have a short natural lifetime of about 4-6 h in snow.
NASA Astrophysics Data System (ADS)
Slaba, Tony C.; Blattnig, Steve R.; Norbury, John W.; Rusek, Adam; La Tessa, Chiara
2016-02-01
The galactic cosmic ray (GCR) simulator at the NASA Space Radiation Laboratory (NSRL) is intended to deliver the broad spectrum of particles and energies encountered in deep space to biological targets in a controlled laboratory setting. In this work, certain aspects of simulating the GCR environment in the laboratory are discussed. Reference field specification and beam selection strategies at NSRL are the main focus, but the analysis presented herein may be modified for other facilities and possible biological considerations. First, comparisons are made between direct simulation of the external, free space GCR field and simulation of the induced tissue field behind shielding. It is found that upper energy constraints at NSRL limit the ability to simulate the external, free space field directly (i.e. shielding placed in the beam line in front of a biological target and exposed to a free space spectrum). Second, variation in the induced tissue field associated with shielding configuration and solar activity is addressed. It is found that the observed variation is likely within the uncertainty associated with representing any GCR reference field with discrete ion beams in the laboratory, given current facility constraints. A single reference field for deep space missions is subsequently identified. Third, a preliminary approach for selecting beams at NSRL to simulate the designated reference field is presented. This approach is not a final design for the GCR simulator, but rather a single step within a broader design strategy. It is shown that the beam selection methodology is tied directly to the reference environment, allows facility constraints to be incorporated, and may be adjusted to account for additional constraints imposed by biological or animal care considerations. The major biology questions are not addressed herein but are discussed in a companion paper published in the present issue of this journal. Drawbacks of the proposed methodology are discussed and weighed against alternative simulation strategies.
Preferential superior surface motion in wear simulations of the Charité total disc replacement.
Goreham-Voss, Curtis M; Vicars, Rachel; Hall, Richard M; Brown, Thomas D
2012-06-01
Laboratory wear simulations of the dual-bearing surface Charité total disc replacement (TDR) are complicated by the non-specificity of the device's center of rotation (CoR). Previous studies have suggested that articulation of the Charité preferentially occurs at the superior-bearing surface, although it is not clear how sensitive this phenomenon is to lubrication conditions or CoR location. In this study, a computational wear model is used to study the articulation kinematics and wear of the Charité TDR. Implant wear was found to be insensitive to the CoR location, although seemingly non-physiologic endplate motion can result. Articulation and wear were biased significantly to the superior-bearing surface, even in the presence of significant perturbations of loading and friction. The computational wear model provides novel insight into the mechanics and wear of the Charité TDR, allowing for better interpretation of in vivo results, and giving useful insight for designing future laboratory physical tests.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Soulami, Ayoub; Lavender, Curt A.; Paxton, Dean M.
2015-06-15
Pacific Northwest National Laboratory (PNNL) has been investigating manufacturing processes for the uranium-10% molybdenum alloy plate-type fuel for high-performance research reactors in the United States. This work supports the U.S. Department of Energy National Nuclear Security Administration’s Office of Material Management and Minimization Reactor Conversion Program. This report documents modeling results of PNNL’s efforts to perform finite-element simulations to predict roll-separating forces for various rolling mill geometries for PNNL, Babcock & Wilcox Co., Y-12 National Security Complex, Los Alamos National Laboratory, and Idaho National Laboratory. The model developed and presented in a previous report has been subjected to further validationmore » study using new sets of experimental data generated from a rolling mill at PNNL. Simulation results of both hot rolling and cold rolling of uranium-10% molybdenum coupons have been compared with experimental results. The model was used to predict roll-separating forces at different temperatures and reductions for five rolling mills within the National Nuclear Security Administration Fuel Fabrication Capability project. This report also presents initial results of a finite-element model microstructure-based approach to study the surface roughness at the interface between zirconium and uranium-10% molybdenum.« less
The influence of past experience on wilderness choice
Alan E. Watson; Joseph W. Roggenbuck; Daniel R. Williams
1991-01-01
A study of Southern Appalachian backcountry hikers tested the hypothesis that recreationists with high experience levels would have greater differentiation of site attribute values when making recreation choices than would individuals with low experience. Contrary to cognitive development theory, a simulated laboratory choice study found that more experienced subjects...
Application of DIVWAG at Rodman Laboratory
1976-03-01
Continue on reveree eide It neceaemry mnd identify by block number) DIVWAG War Game Simulation Mathematical Model 20. ABSTRACT (Continue on...parameters. Rodman Laboratory is using DIVWAG in a simulation mode. In this model of operation, once a game has been completed, a representative...a period of play by a blue (red) artillery battery as a function of range and game time). t Ü UNCLASSIFIED SECURITY CLASSIFICATION OF THIS
Visualizing Energy on Target: Molecular Dynamics Simulations
2017-12-01
ARL-TR-8234 ● DEC 2017 US Army Research Laboratory Visualizing Energy on Target: Molecular Dynamics Simulations by DeCarlos E...return it to the originator. ARL-TR-8234● DEC 2017 US Army Research Laboratory Visualizing Energy on Target: Molecular Dynamics...REPORT TYPE Technical Report 3. DATES COVERED (From - To) 1 October 2015–30 September 2016 4. TITLE AND SUBTITLE Visualizing Energy on Target
Direct modeling of coda wave interferometry: comparison of numerical and experimental approaches
NASA Astrophysics Data System (ADS)
Azzola, Jérôme; Masson, Frédéric; Schmittbuhl, Jean
2017-04-01
The sensitivity of coda waves to small changes of the propagation medium is the principle of the coda waves interferometry, a technique which has been found to have a large range of applications over the past years. It exploits the evolution of strongly scattered waves in a limited region of space, to estimate slight changes like the wave velocity of the medium but also the location of scatterer positions or the stress field. Because of the sensitivity of the method, it is of a great value for the monitoring of geothermal EGS reservoir in order to detect fine changes. The aim of this work is thus to monitor the impact of different scatterer distributions and of the loading condition evolution using coda wave interferometry in the laboratory and numerically by modelling the scatter wavefield. In the laboratory, we analyze the scattering of an acoustic wave through a perforated loaded plate of DURAL. Indeed, the localized damages introduced behave as a scatter source. Coda wave interferometry is performed computing correlations of waveforms under different loading conditions, for different scatter distributions. Numerically, we used SPECFEM2D (a 2D spectral element code, (Komatitsch and Vilotte (1998)) to perform 2D simulations of acoustic and elastic seismic wave propagation and enables a direct comparison with laboratory and field results. An unstructured mesh is thus used to simulate the propagation of a wavelet in a loaded plate, before and after introduction of localized damages. The linear elastic deformation of the plate is simulated using Code Aster. The coda wave interferometry is performed similarly to experimental measurements. The accuracy of the comparison of the numerically and laboratory obtained results is strongly depending on the capacity to adapt the laboratory and numerical simulation conditions. In laboratory, the capacity to illuminate the medium in a similar way to that used in the numerical simulation deeply conditions among others the comparison. In the simulation, the gesture of the mesh and its dispersion also influences the rightness of the comparison and interpretation. Moreover, the spectral elements distribution of the mesh and its relative refinement could also be considered as an interesting scatter source.
Assessment of the Mars Science Laboratory Entry, Descent, and Landing Simulation
NASA Technical Reports Server (NTRS)
Way, David W.; Davis, J. L.; Shidner, Jeremy D.
2013-01-01
On August 5, 2012, the Mars Science Laboratory rover, Curiosity, successfully landed inside Gale Crater. This landing was only the seventh successful landing and fourth rover to be delivered to Mars. Weighing nearly one metric ton, Curiosity is the largest and most complex rover ever sent to investigate another planet. Safely landing such a large payload required an innovative Entry, Descent, and Landing system, which included the first guided entry at Mars, the largest supersonic parachute ever flown at Mars, and a novel and untested Sky Crane landing system. A complete, end-to-end, six degree-of-freedom, multi-body computer simulation of the Mars Science Laboratory Entry, Descent, and Landing sequence was developed at the NASA Langley Research Center. In-flight data gathered during the successful landing is compared to pre-flight statistical distributions, predicted by the simulation. These comparisons provide insight into both the accuracy of the simulation and the overall performance of the vehicle.
Preliminary assessment of the Mars Science Laboratory entry, descent, and landing simulation
NASA Astrophysics Data System (ADS)
Way, David W.
On August 5, 2012, the Mars Science Laboratory rover, Curiosity, successfully landed inside Gale Crater. This landing was the seventh successful landing and fourth rover to be delivered to Mars. Weighing nearly one metric ton, Curiosity is the largest and most complex rover ever sent to investigate another planet. Safely landing such a large payload required an innovative Entry, Descent, and Landing system, which included the first guided entry at Mars, the largest supersonic parachute ever flown at Mars, and the novel Sky Crane landing system. A complete, end-to-end, six degree-of-freedom, multi-body computer simulation of the Mars Science Laboratory Entry, Descent, and Landing sequence was developed at the NASA Langley Research Center. In-flight data gathered during the successful landing is compared to pre-flight statistical distributions, predicted by the simulation. These comparisons provide insight into both the accuracy of the simulation and the overall performance of the Entry, Descent, and Landing system.
Preliminary Assessment of the Mars Science Laboratory Entry, Descent, and Landing Simulation
NASA Technical Reports Server (NTRS)
Way, David W.
2013-01-01
On August 5, 2012, the Mars Science Laboratory rover, Curiosity, successfully landed inside Gale Crater. This landing was only the seventh successful landing and fourth rover to be delivered to Mars. Weighing nearly one metric ton, Curiosity is the largest and most complex rover ever sent to investigate another planet. Safely landing such a large payload required an innovative Entry, Descent, and Landing system, which included the first guided entry at Mars, the largest supersonic parachute ever flown at Mars, and a novel and untested Sky Crane landing system. A complete, end-to-end, six degree-of-freedom, multibody computer simulation of the Mars Science Laboratory Entry, Descent, and Landing sequence was developed at the NASA Langley Research Center. In-flight data gathered during the successful landing is compared to pre-flight statistical distributions, predicted by the simulation. These comparisons provide insight into both the accuracy of the simulation and the overall performance of the vehicle.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Habte, A.; Andreas, A.; Ottoson, L.
2014-11-01
Indoor and outdoor testing of photovoltaic (PV) device performance requires the use of solar simulators and natural solar radiation, respectively. This performance characterization requires accurate knowledge of spectral irradiance distribution that is incident on the devices. Spectroradiometers are used to measure the spectral distribution of solar simulators and solar radiation. On September 17, 2013, a global spectral irradiance intercomparison using spectroradiometers was organized by the Solar Radiation Research Laboratory (SRRL) at the National Renewable Energy Laboratory (NREL). This paper presents highlights of the results of this first intercomparison, which will help to decrease systematic inter-laboratory differences in the measurements ofmore » the outputs or efficiencies of PV devices and harmonize laboratory experimental procedures.« less
Interstellar and Planetary Analogs in the Laboratory
NASA Technical Reports Server (NTRS)
Salama, Farid
2013-01-01
We present and discuss the unique capabilities of the laboratory facility, COSmIC, that was developed at NASA Ames to investigate the interaction of ionizing radiation (UV, charged particles) with molecular species (neutral molecules, radicals and ions) and carbonaceous grains in the Solar System and in the Interstellar Medium (ISM). COSmIC stands for Cosmic Simulation Chamber, a laboratory chamber where interstellar and planetary analogs are generated, processed and analyzed. It is composed of a pulsed discharge nozzle (PDN) expansion that generates a free jet supersonic expansion in a plasma cavity coupled to two ultrahigh-sensitivity, complementary in situ diagnostics: a cavity ring down spectroscopy (CRDS) system for photonic detection and a Reflectron time-of-flight mass spectrometer (ReTOF-MS) for mass detection. This setup allows the study of molecules, ions and solids under the low temperature and high vacuum conditions that are required to simulate some interstellar, circumstellar and planetary physical environments providing new fundamental insights on the molecular level into the processes that are critical to the chemistry in the ISM, circumstellar and planet forming regions, and on icy objects in the Solar System. Recent laboratory results that were obtained using COSmIC will be discussed, in particular the progress that have been achieved in monitoring in the laboratory the formation of solid particles from their gas-phase molecular precursors in environments as varied as circumstellar outflow and planetary atmospheres.
Ecological Validity of the Testing Effect: The Use of Daily Quizzes in Introductory Psychology
ERIC Educational Resources Information Center
Batsell, W. Robert, Jr.; Perry, Jennifer L.; Hanley, Elizabeth; Hostetter, Autumn B.
2017-01-01
The testing effect is the enhanced retention of learned information by individuals who have studied and completed a test over the material relative to individuals who have only studied the material. Although numerous laboratory studies and simulated classroom studies have provided evidence of the testing effect, data from a natural class setting…
NASA Technical Reports Server (NTRS)
Vaughan, O. H., Jr.; Hung, R. J.
1975-01-01
Skylab 4 crew members performed a series of demonstrations showing the oscillations, rotations, as well as collision coalescence of water droplets which simulate various physical models of fluids under low gravity environment. The results from Skylab demonstrations provide information and illustrate the potential of an orbiting space-oriented research laboratory for the study of more sophisticated fluid mechanic experiments. Experiments and results are discussed.
Simulation of a group of rangefinders adapted to alterations of measurement angle
NASA Astrophysics Data System (ADS)
Baikov, D. V.; Pastushkova, A. A.; Danshin, V. V.; Chepin, E. V.
2017-01-01
As part of the National Research Nuclear University of National Research Nuclear University MEPhI (MEPhI) at the Department of Computer Systems and Technologies working laboratory "Robotics." University teachers and laboratory staff implement a training program for master's program "Computer technology in robotics." Undergraduates and graduate students conduct laboratory research and development in several promising areas in robotics. One of the methodologies that are actively used in carrying out dissertation research is the modeling of advanced hardware and software systems, robotics. This article presents the results of such a study. The purpose of this article is to simulate a sensor comprised of a group of laser rangefinders. The rangefinders should be simulated according to the following principle. Beams will originate from one point though with a deviation from normal, providing thereby simultaneous scanning of different points. The data obtained in our virtual test room should be used to indicate an average distance from the device to obstacles for all the four sensors in real time. By leveling the divergence angle of the beams we can simulate different kinds of rangefinders (laser and ultrasonic ones). By adjusting noise parameters we can achieve results similar to those of real models (rangefinders), and obtain a surface map displaying irregularities. We should use a model of an aircraft (quadcopter) as a device to install the sensor. In the article we made an overview of works on rangefinder simulation undertaken at institutions around the world and performed tests. The article draws a conclusion about the relevance of the suggested approach, the methods used, necessity and feasibility of further research in this area.
Integration of Simulation into Pre-Laboratory Chemical Course: Computer Cluster versus WebCT
ERIC Educational Resources Information Center
Limniou, Maria; Papadopoulos, Nikos; Whitehead, Christopher
2009-01-01
Pre-laboratory activities have been known to improve students' preparation before their practical work as they assist students to make available more working memory capacity for actual learning during the laboratory. The aim of this investigation was to compare two different teaching approaches which supported a pre-laboratory session by using the…
Marketing and Distribution: What About Training Plans in the DE Project Laboratory?
ERIC Educational Resources Information Center
Snyder, Ruth
1977-01-01
Managing a distributive education (DE) laboratory is a challenge. The laboratory is the simulated training station, with the instructor taking on the role of employer, managing student activities and learning. One tool to be utilized in managing a DE laboratory is a training plan. This article discusses the need for student training plans and the…
Study of physiological responses to acute carbon monoxide exposure with a human patient simulator.
Cesari, Whitney A; Caruso, Dominique M; Zyka, Enela L; Schroff, Stuart T; Evans, Charles H; Hyatt, Jon-Philippe K
2006-12-01
Human patient simulators are widely used to train health professionals and students in a clinical setting, but they also can be used to enhance physiology education in a laboratory setting. Our course incorporates the human patient simulator for experiential learning in which undergraduate university juniors and seniors are instructed to design, conduct, and present (orally and in written form) their project testing physiological adaptation to an extreme environment. This article is a student report on the physiological response to acute carbon monoxide exposure in a simulated healthy adult male and a coal miner and represents how 1) human patient simulators can be used in a nonclinical way for experiential hypothesis testing; 2) students can transition from traditional textbook learning to practical application of their knowledge; and 3) student-initiated group investigation drives critical thought. While the course instructors remain available for consultation throughout the project, the relatively unstructured framework of the assignment drives the students to create an experiment independently, troubleshoot problems, and interpret the results. The only stipulation of the project is that the students must generate an experiment that is physiologically realistic and that requires them to search out and incorporate appropriate data from primary scientific literature. In this context, the human patient simulator is a viable educational tool for teaching integrative physiology in a laboratory environment by bridging textual information with experiential investigation.
Laboratory experiments to investigate sublimation rates of water ice in nighttime lunar regolith
NASA Astrophysics Data System (ADS)
Piquette, Marcus; Horányi, Mihály; Stern, S. Alan
2017-09-01
The existence of water ice on the lunar surface has been a long-standing topic with implications for both lunar science and in-situ resource utilization (ISRU). Cold traps on the lunar surface may have conditions necessary to retain water ice, but no laboratory experiments have been conducted to verify modeling results. We present an experiment testing the ability to thermally control bulk samples of lunar regolith simulant mixed with water ice under vacuum in an effort to constrain sublimation rates. The simulant used was JSC-1A lunar regolith simulant developed by NASA's Johnson Space Center. Samples with varying ratios of water ice and JSC-1A regolith simulant, totally about 1 kg, were placed under vacuum and cooled to 100 K to simulate conditions in lunar cold traps. The resulting sublimation of water ice over an approximately five-day period was measured by comparing the mass of the samples before and after the experimental run. Our results indicate that water ice in lunar cold traps is stable on timescales comparable to the lunar night, and should continue to be studied as possible resources for future utilization. This experiment also gauges the efficacy of the synthetic lunar atmosphere mission (SLAM) as a low-cost water resupply mission to lunar outposts.
Simulator training to minimize ionizing radiation exposure in the catheterization laboratory.
Katz, Aric; Shtub, Avraham; Solomonica, Amir; Poliakov, Adva; Roguin, Ariel
2017-03-01
To learn about radiation and how to lower it. Patients and operators are routinely exposed to high doses of ionizing radiation during catheterization procedures. This increased exposure to ionizing radiation is partially due to a lack of awareness to the effects of ionizing radiation, and lack of knowledge on the distribution and behavior of scattered radiation. A simulator, which incorporates data on scattered ionizing radiation, was built based on multiple phantom measurements and used for teaching radiation safety. The validity of the simulator was confirmed in three catheterization laboratories and tested by 20 interventional cardiologists. All evaluators were tested by an objective knowledge examination before, immediately following, and 12 weeks after simulator-based learning and training. A subjective Likert questionnaire on satisfaction with simulation-based learning and training was also completed. The 20 evaluators learned and retained the knowledge that they gained from using the simulator: the average scores of the knowledge examination pre-simulator training was 54 ± 15% (mean ± standard deviation), and this score significantly increased after training to 94 ± 10% (p < 0.001). The evaluators also reported high levels of satisfaction following simulation-based learning and training according to the results of the subjective Likert questionnaire. Simulators can be used to train cardiology staff and fellows and to further educate experienced personnel on radiation safety. As a result of simulator training, the operator gains knowledge, which can then be applied in the catheterization laboratory in order to reduce radiation doses to the patient and to the operator, thereby improving the safety of the intervention.
Simulation of the dynamic environment for missile component testing: Demonstration
NASA Technical Reports Server (NTRS)
Chang, Kurng Y.
1989-01-01
The problems in defining a realistic test requirement for missile and space vehicle components can be classified into two categories: (1) definition of the test environment representing the expected service condition, and (2) simulation of the desired environment in the test laboratory. Recently, a new three-dimensional (3-D) test facility was completed at the U.S. Army Harry Diamond Laboratory (HDL) to simulate triaxial vibration input to a test specimen. The vibration test system is designed to support multi-axial vibration tests over the frequency range of 5 to 2000 Hertz. The availability of this 3-D test system motivates the development of new methodologies addressing environmental definition and simulation.
Advances in Discrete-Event Simulation for MSL Command Validation
NASA Technical Reports Server (NTRS)
Patrikalakis, Alexander; O'Reilly, Taifun
2013-01-01
In the last five years, the discrete event simulator, SEQuence GENerator (SEQGEN), developed at the Jet Propulsion Laboratory to plan deep-space missions, has greatly increased uplink operations capacity to deal with increasingly complicated missions. In this paper, we describe how the Mars Science Laboratory (MSL) project makes full use of an interpreted environment to simulate change in more than fifty thousand flight software parameters and conditional command sequences to predict the result of executing a conditional branch in a command sequence, and enable the ability to warn users whenever one or more simulated spacecraft states change in an unexpected manner. Using these new SEQGEN features, operators plan more activities in one sol than ever before.
Multi-Modal Transportation System Simulation
DOT National Transportation Integrated Search
1971-01-01
THE PRESENT STATUS OF A LABORATORY BEING DEVELOPED FOR REAL-TIME SIMULATION OF COMMAND AND CONTROL FUNCTIONS IN TRANSPORTATION SYSTEMS IS DISCUSSED. DETAILS ARE GIVEN ON THE SIMULATION MODELS AND ON PROGRAMMING TECHNIQUES USED IN DEFINING AND EVALUAT...
Numerical simulations of catastrophic disruption: Recent results
NASA Technical Reports Server (NTRS)
Benz, W.; Asphaug, E.; Ryan, E. V.
1994-01-01
Numerical simulations have been used to study high velocity two-body impacts. In this paper, a two-dimensional Largrangian finite difference hydro-code and a three-dimensional smooth particle hydro-code (SPH) are described and initial results reported. These codes can be, and have been, used to make specific predictions about particular objects in our solar system. But more significantly, they allow us to explore a broad range of collisional events. Certain parameters (size, time) can be studied only over a very restricted range within the laboratory; other parameters (initial spin, low gravity, exotic structure or composition) are difficult to study at all experimentally. The outcomes of numerical simulations lead to a more general and accurate understanding of impacts in their many forms.
A Fast-Time Simulation Environment for Airborne Merging and Spacing Research
NASA Technical Reports Server (NTRS)
Bussink, Frank J. L.; Doble, Nathan A.; Barmore, Bryan E.; Singer, Sharon
2005-01-01
As part of NASA's Distributed Air/Ground Traffic Management (DAG-TM) effort, NASA Langley Research Center is developing concepts and algorithms for merging multiple aircraft arrival streams and precisely spacing aircraft over the runway threshold. An airborne tool has been created for this purpose, called Airborne Merging and Spacing for Terminal Arrivals (AMSTAR). To evaluate the performance of AMSTAR and complement human-in-the-loop experiments, a simulation environment has been developed that enables fast-time studies of AMSTAR operations. The environment is based on TMX, a multiple aircraft desktop simulation program created by the Netherlands National Aerospace Laboratory (NLR). This paper reviews the AMSTAR concept, discusses the integration of the AMSTAR algorithm into TMX and the enhancements added to TMX to support fast-time AMSTAR studies, and presents initial simulation results.
The Automated Primate Research Laboratory (APRL)
NASA Technical Reports Server (NTRS)
Pace, N.; Smith, G. D.
1972-01-01
A description is given of a self-contained automated primate research laboratory to study the effects of weightlessness on subhuman primates. Physiological parameters such as hemodynamics, respiration, blood constituents, waste, and diet and nutrition are analyzed for abnormalities in the simulated space environment. The Southeast Asian pig-tailed monkey (Macaca nemistrina) was selected for the experiments owing to its relative intelligence and learning capacity. The objective of the program is to demonstrate the feasibility of a man-tended primate space flight experiment.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fox, K. M.; Edwards, T. B.; Mcclane, D. L.
2016-03-01
In this report, Savannah River National Laboratory provides chemical analyses and Product Consistency Test (PCT) results for a series of simulated high level waste (HLW) glasses fabricated by Pacific Northwest National Laboratory (PNNL) as part of an ongoing nepheline crystallization study. The results of these analyses will be used to improve the ability to predict crystallization of nepheline as a function of composition and heat treatment for glasses formulated at high alumina concentrations.
Space Weathering: Laboratory Analyses and In-Situ Instrumentation
NASA Technical Reports Server (NTRS)
Bentley, M. S.; Ball, A. J.; Dyar, M. D.; Pieters, C. M.; Wright, I. P.; Zarnecki, J. C.
2005-01-01
Space weathering is now understood to be a key modifier of visible and near infrared reflectance spectra of airless bodies. Believed to be caused by vapour recondensation after either ion sputtering or impact vaporization, space weathering has been successfully simulated in the laboratory over the past few years. The optical changes caused by space weathering have been attributed to the accumulation of sub-microscopic iron on regolith grain surfaces. Such fine-grained metallic iron has distinctive magnetic properties that can be used to study it.
Pai, Hsiang-Chu
2016-10-01
The use of clinical simulation in undergraduate nursing programs in Taiwan has gradually increased over the past 5years. Previous research has shown that students' experience of anxiety during simulated laboratory sessions influences their self-reflection and learning effectiveness. Thus, further study that tracks what influences students' clinical performance in actual clinical sites is vital. The aim of the study is to develop an integrated model that considers the associations among anxiety, self-reflection, and learning effectiveness and to understand how this model applies to student nurses' clinical performance while on clinical placement. This study used a correlational and longitudinal study design. The 80 nursing students, who ranged in age from 19 to 21 (mean=20.38, SD=0.56), were recruited from a nursing school in southern Taiwan. Data were collected during three phases of implementation using four questionnaires. During the first phase, the State-Trait Anxiety Inventory (STAI), Simulation Learning Effectiveness Scale (SLES), and Self-Reflection and Insight Scale (SRIS) were used after students completed the simulation course in the school simulation laboratory. Nursing students also completed the Holistic Nursing Competence Scale at 2months (Phase 2) and 4months (Phase 3) after clinical practice experience. In Phase 3, students again completed the STAI and SRIS. Partial least squares (PLS), a structural equation modeling (SEM) procedure, was used to test the research model. The findings showed that: (1) at the start of the simulation laboratory, anxiety had a significant negative effect on students' simulation learning effectiveness (SLE; β=-0.14, p<0.05) and on self-reflection with insight (SRI; β=-0.52, p<0.01). Self-reflection also had a significant positive effect on simulation learning effectiveness (β=0.37, p<0.01). Anxiety had a significant negative effect on students' nursing competence during the first 2months of practice in a clinical nursing site (β=-0.20, p<0.01). Simulation learning effectiveness and self-reflection and insight also had a significant positive effect on nursing competence during the first 2months of practice in a clinical site (β=0.13; β=0.16, p<0.05), respectively; and (2) when students practice in a clinical setting, their previous experience of nursing competence during the first 2months of clinical care and their self-reflection and insight have a significant positive effect on their 4-month nursing competence (β=0.58; β=0.27, p<0.01). Anxiety, however, had a negative effect on 4-month nursing competence but not significantly. Overall, 41% of the variance in clinical nursing performance was accounted for by the variables in the integrated model. This study highlights that self-reflection with insight and clinical experience may help students to deflect anxiety that may influence the development of clinical competence. Of note is that real-life clinical experience has a stronger effect on enhancing clinical performance than does a simulation experience. Copyright © 2016 Elsevier Ltd. All rights reserved.
Use of Simulation Technology in Dental Education.
ERIC Educational Resources Information Center
Buchanan, Judith Ann
2001-01-01
Discusses the impact of current simulation laboratories on dental education and reviews advanced technology simulation that has recently become available or is in the developmental stage. Addresses the abilities of advanced technology simulation, its advantages and disadvantages, and its potential to affect dental education. (EV)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wiedenman, B. J.; White, T. L.; Mahannah, R. N.
Ion Chromatography (IC) is the principal analytical method used to support studies of Sludge Reciept and Adjustment Tank (SRAT) chemistry at DWPF. A series of prior analytical ''Round Robin'' (RR) studies included both supernate and sludge samples from SRAT simulant, previously reported as memos, are tabulated in this report.2,3 From these studies it was determined to standardize IC column size to 4 mm diameter, eliminating the capillary column from use. As a follow on test, the DWPF laboratory, the PSAL laboratory, and the AD laboratory participated in the current analytical RR to determine a suite of anions in SRAT simulantmore » by IC, results also are tabulated in this report. The particular goal was to confirm the laboratories ability to measure and quantitate glycolate ion. The target was + or - 20% inter-lab agreement of the analyte averages for the RR. Each of the three laboratories analyzed a batch of 12 samples. For each laboratory, the percent relative standard deviation (%RSD) of the averages on nitrate, glycolate, and oxalate, was 10% or less. The three laboratories all met the goal of 20% relative agreement for nitrate and glycolate. For oxalate, the PSAL laboratory reported an average value that was 20% higher than the average values reported by the DWPF laboratory and the AD laboratory. Because of this wider window of agreement, it was concluded to continue the practice of an additional acid digestion for total oxalate measurement. It should also be noted that large amounts of glycolate in the SRAT samples will have an impact on detection limits of near eluting peaks, namely Fluoride and Formate. A suite of scoping experiments are presented in the report to identify and isolate other potential interlaboratory disceprancies. Specific ion chromatography inter-laboratory method conditions and differences are tabulated. Most differences were minor but there are some temperature control equipment differences that are significant leading to a recommendation of a heated jacket for analytical columns that are remoted for use in radiohoods. A suggested method improvement would be to implement column temperture control at a temperature slightly above ambient to avoid peak shifting due to temperature fluctuations. Temperature control in this manner would improve short and longer term peak retention time stability. An unknown peak was observed during the analysis of glycolic acid and SRAT simulant. The unknown peak was determined to best match diglycolic acid. The development of a method for acetate is summaraized, and no significant amount of acetate was observed in the SRAT products tested. In addition, an alternative Gas Chromatograph (GC) method for glycolate is summarized.« less
NASA Astrophysics Data System (ADS)
Yücel, M.; Emirhan, E.; Bayrak, A.; Ozben, C. S.; Yücel, E. Barlas
2015-11-01
Design and production of a simple and low cost X-ray imaging system that can be used for light industrial applications was targeted in the Nuclear Physics Laboratory of Istanbul Technical University. In this study, production, transmission and detection of X-rays were simulated for the proposed imaging device. OX/70-P dental tube was used and X-ray spectra simulated by Geant4 were validated by comparison with X-ray spectra measured between 20 and 35 keV. Relative detection efficiency of the detector was also determined to confirm the physics processes used in the simulations. Various time optimization tools were performed to reduce the simulation time.
Interprofessional Education Among Student Health Professionals Using Human Patient Simulation
Chmil, Joyce V.
2014-01-01
Objective. To describe the planning, implementation, and outcomes of an interprofessional education clinical laboratory facilitated through human patient simulation. Design. An interprofessional education clinical laboratory was developed with a patient-care scenario of acute exacerbation of heart failure that incorporated the use of a high-fidelity patient simulator. Pharmacy and nursing students assumed clinical roles in this realistic scenario and collaborated to diagnose and treat the patient. Assessment. Student attitudes toward and readiness to participate in interprofessional education improved following participation in the laboratory. Students reported that the greatest benefit of the experience was in their communication skills. Conclusion. Students’ ability to participate in interprofessional education experiences and their attitudes toward them improved following participation in this curricular initiative. Further evaluation of the impact of interprofessional education on student learning outcomes and changes in practice is warranted. PMID:24954934
NASA Astrophysics Data System (ADS)
Bocchi, M.; Ummels, B.; Chittenden, J. P.; Lebedev, S. V.
2012-02-01
In the context of high energy density laboratory astrophysics, we aim to produce and study a rotating plasma relevant to accretion discs physics. We devised an experimental setup based on a modified cylindrical wire array and we studied it numerically with the three-dimensional, resistive magneto-hydrodynamic code GORGON. The simulations show that a rotating plasma cylinder is formed, with typical rotation velocity ~35 km/s and Mach number ~5. In addition, the plasma ring is differentially rotating and strongly radiatively cooled. The introduction of external magnetic fields is discussed.
Benchmark Problems of the Geothermal Technologies Office Code Comparison Study
DOE Office of Scientific and Technical Information (OSTI.GOV)
White, Mark D.; Podgorney, Robert; Kelkar, Sharad M.
A diverse suite of numerical simulators is currently being applied to predict or understand the performance of enhanced geothermal systems (EGS). To build confidence and identify critical development needs for these analytical tools, the United States Department of Energy, Geothermal Technologies Office has sponsored a Code Comparison Study (GTO-CCS), with participants from universities, industry, and national laboratories. A principal objective for the study was to create a community forum for improvement and verification of numerical simulators for EGS modeling. Teams participating in the study were those representing U.S. national laboratories, universities, and industries, and each team brought unique numerical simulationmore » capabilities to bear on the problems. Two classes of problems were developed during the study, benchmark problems and challenge problems. The benchmark problems were structured to test the ability of the collection of numerical simulators to solve various combinations of coupled thermal, hydrologic, geomechanical, and geochemical processes. This class of problems was strictly defined in terms of properties, driving forces, initial conditions, and boundary conditions. Study participants submitted solutions to problems for which their simulation tools were deemed capable or nearly capable. Some participating codes were originally developed for EGS applications whereas some others were designed for different applications but can simulate processes similar to those in EGS. Solution submissions from both were encouraged. In some cases, participants made small incremental changes to their numerical simulation codes to address specific elements of the problem, and in other cases participants submitted solutions with existing simulation tools, acknowledging the limitations of the code. The challenge problems were based on the enhanced geothermal systems research conducted at Fenton Hill, near Los Alamos, New Mexico, between 1974 and 1995. The problems involved two phases of research, stimulation, development, and circulation in two separate reservoirs. The challenge problems had specific questions to be answered via numerical simulation in three topical areas: 1) reservoir creation/stimulation, 2) reactive and passive transport, and 3) thermal recovery. Whereas the benchmark class of problems were designed to test capabilities for modeling coupled processes under strictly specified conditions, the stated objective for the challenge class of problems was to demonstrate what new understanding of the Fenton Hill experiments could be realized via the application of modern numerical simulation tools by recognized expert practitioners.« less
Numerical assessment of bureau of mines electric arc melter
DOE Office of Scientific and Technical Information (OSTI.GOV)
Paik, S.; Hawkes, G.; Nguyen, H.D.
1994-12-31
An electric arc melter used for the waste treatment process at Idaho National Engineering Laboratory (INEL) in cooperation with the U.S. Bureau of Mines (USBM) has been numerically studied. The arc melter is being used for vitrification of thermally oxidized, buried, transuranic (TRU) contaminated wastes by INEL in conjunction with the USBM as a part of the Buried Waste Integrated Demonstration project. The purpose of this study is to numerically investigate the performance of the laboratory-scale arc melter simulating the USBM arc melter. Initial results of modeling the full-scale USBM arc melter are also reported in this paper.
Tritium safety study using Caisson Assembly (CATS) at TPL/JAEA
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hayashi, T.; Kobayashi, K.; Iwai, Y.
Tritium confinement is required as the most important safety Junction for a fusion reactor. In order to demonstrate the confinement performance experimentally, an unique equipment, called CATS: Caisson Assembly for Tritium Safety study, was installed in Tritium Process Laboratory of Japan Atomic Energy Agency and operated for about 10 years. Tritium confinement and migration data in CATS have been accumulated and dynamic simulation code was accumulated using these data. Contamination and decontamination behavior on various materials and new safety equipment functions have been investigated under collaborations with a lot of laboratories and universities. (authors)
Mixed-field GCR Simulations for Radiobiological Research using Ground Based Accelerators
NASA Astrophysics Data System (ADS)
Kim, Myung-Hee Y.; Rusek, Adam; Cucinotta, Francis
Space radiation is comprised of a large number of particle types and energies, which have differential ionization power from high energy protons to high charge and energy (HZE) particles and secondary neutrons produced by galactic cosmic rays (GCR). Ground based accelerators such as the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL) are used to simulate space radiation for radiobiology research and dosimetry, electronics parts, and shielding testing using mono-energetic beams for single ion species. As a tool to support research on new risk assessment models, we have developed a stochastic model of heavy ion beams and space radiation effects, the GCR Event-based Risk Model computer code (GERMcode). For radiobiological research on mixed-field space radiation, a new GCR simulator at NSRL is proposed. The NSRL-GCR simulator, which implements the rapid switching mode and the higher energy beam extraction to 1.5 GeV/u, can integrate multiple ions into a single simulation to create GCR Z-spectrum in major energy bins. After considering the GCR environment and energy limitations of NSRL, a GCR reference field is proposed after extensive simulation studies using the GERMcode. The GCR reference field is shown to reproduce the Z and LET spectra of GCR behind shielding within 20 percents accuracy compared to simulated full GCR environments behind shielding. A major challenge for space radiobiology research is to consider chronic GCR exposure of up to 3-years in relation to simulations with cell and animal models of human risks. We discuss possible approaches to map important biological time scales in experimental models using ground-based simulation with extended exposure of up to a few weeks and fractionation approaches at a GCR simulator.
Mixed-field GCR Simulations for Radiobiological Research Using Ground Based Accelerators
NASA Technical Reports Server (NTRS)
Kim, Myung-Hee Y.; Rusek, Adam; Cucinotta, Francis A.
2014-01-01
Space radiation is comprised of a large number of particle types and energies, which have differential ionization power from high energy protons to high charge and energy (HZE) particles and secondary neutrons produced by galactic cosmic rays (GCR). Ground based accelerators such as the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL) are used to simulate space radiation for radiobiology research and dosimetry, electronics parts, and shielding testing using mono-energetic beams for single ion species. As a tool to support research on new risk assessment models, we have developed a stochastic model of heavy ion beams and space radiation effects, the GCR Event-based Risk Model computer code (GERMcode). For radiobiological research on mixed-field space radiation, a new GCR simulator at NSRL is proposed. The NSRL-GCR simulator, which implements the rapid switching mode and the higher energy beam extraction to 1.5 GeV/u, can integrate multiple ions into a single simulation to create GCR Z-spectrum in major energy bins. After considering the GCR environment and energy limitations of NSRL, a GCR reference field is proposed after extensive simulation studies using the GERMcode. The GCR reference field is shown to reproduce the Z and LET spectra of GCR behind shielding within 20% accuracy compared to simulated full GCR environments behind shielding. A major challenge for space radiobiology research is to consider chronic GCR exposure of up to 3-years in relation to simulations with cell and animal models of human risks. We discuss possible approaches to map important biological time scales in experimental models using ground-based simulation with extended exposure of up to a few weeks and fractionation approaches at a GCR simulator.
Paseiro-Cerrato, Rafael; Tongchat, Chinawat; Franz, Roland
2016-05-01
This study evaluated the influence of parameters such as temperature and type of low-density polyethylene (LDPE) film on the log Kp/f values of seven model migrants in food simulants. Two different types of LDPE films contaminated by extrusion and immersion were placed in contact with three food simulants including 20% ethanol, 50% ethanol and olive oil under several time-temperature conditions. Results suggest that most log Kp/f values are little affected by these parameters in this study. In addition, the relation between log Kp/f and log Po/w was established for each food simulant and regression lines, as well as correlation coefficients, were calculated. Correlations were compared with data from real foodstuffs. Data presented in this study could be valuable in assigning certain foods to particular food simulants as well as predicting the mass transfer of potential migrants into different types of food or food simulants, avoiding tedious and expensive laboratory analysis. The results could be especially useful for regulatory agencies as well as for the food industry.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kawamura, Yoshiyuki
The radiative forcing of the greenhouse gases has been studied being based on computational simulations or the observation of the real atmosphere meteorologically. In order to know the greenhouse effect more deeply and to study it from various viewpoints, the study on it in a laboratory scale is important. We have developed a direct measurement system for the infrared back radiation from the carbon dioxide (CO{sub 2}) gas. The system configuration is similar with that of the practical earth-atmosphere-space system. Using this system, the back radiation from the CO{sub 2} gas was directly measured in a laboratory scale, which roughlymore » coincides with meteorologically predicted value.« less
NASA Astrophysics Data System (ADS)
Mori, H.; Trevisan, L.; Sakaki, T.; Cihan, A.; Smits, K. M.; Illangasekare, T. H.
2013-12-01
Multiphase flow models can be used to improve our understanding of the complex behavior of supercritical CO2 (scCO2) in deep saline aquifers to make predictions for the stable storage strategies. These models rely on constitutive relationships such as capillary pressure (Pc) - saturation (Sw) and relative permeability (kr) - saturation (Sw) as input parameters. However, for practical application of these models, such relationships for scCO2 and brine system are not readily available for geological formations. This is due to the complicated and expensive traditional methods often used to obtain these relationships in the laboratory through high pressure and/or high-temperature controls. A method that has the potential to overcome the difficulty in conducting such experiments is to replicate scCO2 and brine with surrogate fluids that capture the density and viscosity effects to obtain the constitutive relationships under ambient conditions. This study presents an investigation conducted to evaluate this method. An assessment of the method allows us to evaluate the prediction accuracy of multiphase models using the constitutive relationships developed from this approach. With this as a goal, the study reports multiple laboratory column experiments conducted to measure these relationships. The obtained relationships were then used in the multiphase flow simulator TOUGH2 T2VOC to explore capillary trapping mechanisms of scCO2. A comparison of the model simulation to experimental observation was used to assess the accuracy of the measured constitutive relationships. Experimental data confirmed, as expected, that the scaling method cannot be used to obtain the residual and irreducible saturations. The results also showed that the van Genuchten - Mualem model was not able to match the independently measured kr data obtained from column experiments. Simulated results of fluid saturations were compared with saturation measurements obtained using x-ray attenuations. This comparison demonstrated that the experimentally derived constitutive relationships matched the experimental data more accurately than the simulation using constitutive relationships derived from scaling methods and van Genuchten - Mualem model. However, simulated imbibition fronts did not match well, suggesting the need for further study. In general, the study demonstrated the feasibility of using surrogate fluids to obtain both Pc - Sw and kr - Sw relationships to be used in multiphase models of scCO2 migration and entrapment.
Comparing field investigations with laboratory models to predict landfill leachate emissions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fellner, Johann; Doeberl, Gernot; Allgaier, Gerhard
2009-06-15
Investigations into laboratory reactors and landfills are used for simulating and predicting emissions from municipal solid waste landfills. We examined water flow and solute transport through the same waste body for different volumetric scales (laboratory experiment: 0.08 m{sup 3}, landfill: 80,000 m{sup 3}), and assessed the differences in water flow and leachate emissions of chloride, total organic carbon and Kjeldahl nitrogen. The results indicate that, due to preferential pathways, the flow of water in field-scale landfills is less uniform than in laboratory reactors. Based on tracer experiments, it can be discerned that in laboratory-scale experiments around 40% of pore watermore » participates in advective solute transport, whereas this fraction amounts to less than 0.2% in the investigated full-scale landfill. Consequences of the difference in water flow and moisture distribution are: (1) leachate emissions from full-scale landfills decrease faster than predicted by laboratory experiments, and (2) the stock of materials remaining in the landfill body, and thus the long-term emission potential, is likely to be underestimated by laboratory landfill simulations.« less
Makransky, Guido; Bonde, Mads T; Wulff, Julie S G; Wandall, Jakob; Hood, Michelle; Creed, Peter A; Bache, Iben; Silahtaroglu, Asli; Nørremølle, Anne
2016-03-25
Simulation based learning environments are designed to improve the quality of medical education by allowing students to interact with patients, diagnostic laboratory procedures, and patient data in a virtual environment. However, few studies have evaluated whether simulation based learning environments increase students' knowledge, intrinsic motivation, and self-efficacy, and help them generalize from laboratory analyses to clinical practice and health decision-making. An entire class of 300 University of Copenhagen first-year undergraduate students, most with a major in medicine, received a 2-h training session in a simulation based learning environment. The main outcomes were pre- to post- changes in knowledge, intrinsic motivation, and self-efficacy, together with post-intervention evaluation of the effect of the simulation on student understanding of everyday clinical practice were demonstrated. Knowledge (Cohen's d = 0.73), intrinsic motivation (d = 0.24), and self-efficacy (d = 0.46) significantly increased from the pre- to post-test. Low knowledge students showed the greatest increases in knowledge (d = 3.35) and self-efficacy (d = 0.61), but a non-significant increase in intrinsic motivation (d = 0.22). The medium and high knowledge students showed significant increases in knowledge (d = 1.45 and 0.36, respectively), motivation (d = 0.22 and 0.31), and self-efficacy (d = 0.36 and 0.52, respectively). Additionally, 90 % of students reported a greater understanding of medical genetics, 82 % thought that medical genetics was more interesting, 93 % indicated that they were more interested and motivated, and had gained confidence by having experienced working on a case story that resembled the real working situation of a doctor, and 78 % indicated that they would feel more confident counseling a patient after the simulation. The simulation based learning environment increased students' learning, intrinsic motivation, and self-efficacy (although the strength of these effects differed depending on their pre-test knowledge), and increased the perceived relevance of medical educational activities. The results suggest that simulations can help future generations of doctors transfer new understanding of disease mechanisms gained in virtual laboratory settings into everyday clinical practice.
Davy, Jonathan; Göbel, Matthias
2013-01-01
This study compared the effects of a 1 h self-selected recovery period to those of a standard night shift arrangement (with a total break time of 1-h) over a simulated three-day night shift schedule in a laboratory setting. Results showed that the inclusion of the flexible nap scheme resulted in higher performance output, improvements in physiological strain responses and reduced sleepiness during each night shift and generally over the three-night cycle. Certain variables also revealed the impact of napping compared with the standard rest break condition on the circadian rhythm. The sleep diary records show that the inclusion of the current intervention did not significantly reduce daytime recovery sleep. The results suggest that the potential benefits of flexible napping may outweigh the logistical effort it requires in a workplace environment. Consensus on appropriate napping strategies for shift work remains a challenge. This simulated night shift laboratory study sought to determine the effects of a 1-h self-selected nap opportunity relative to a normal shift set-up. The nap improved performance and decreased sleepiness, without affecting daytime sleep.
Studying marine stratus with large eddy simulation
NASA Technical Reports Server (NTRS)
Moeng, Chin-Hoh
1990-01-01
Data sets from field experiments over the stratocumulus regime may include complications from larger scale variations, decoupled cloud layers, diurnal cycle, or entrainment instability, etc. On top of the already complicated turbulence-radiation-condensation processes within the cloud-topped boundary layer (CTBL), these complexities may sometimes make interpretation of the data sets difficult. To study these processes, a better understanding is needed of the basic processes involved in the prototype CTBL. For example, is cloud top radiative cooling the primary source of the turbulent kinetic energy (TKE) within the CTBL. Historically, laboratory measurements have played an important role in addressing the turbulence problems. The CTBL is a turbulent field which is probably impossible to generate in laboratories. Large eddy simulation (LES) is an alternative way of 'measuring' the turbulent structure under controlled environments, which allows the systematic examination of the basic physical processes involved. However, there are problems with the LES approach for the CTBL. The LES data need to be consistent with the observed data. The LES approach is discussed, and results are given which provide some insights into the simulated turbulent flow field. Problems with this approach for the CTBL and information from the FIRE experiment needed to justify the LES results are discussed.
Analysis of Computational Models of Shaped Charges for Jet Formation and Penetration
NASA Astrophysics Data System (ADS)
Haefner, Jonah; Ferguson, Jim
2016-11-01
Shaped charges came into use during the Second World War demonstrating the immense penetration power of explosively formed projectiles and since has become a tool used by nearly every nation in the world. Penetration is critically dependent on how the metal liner is collapsed into a jet. The theory of jet formation has been studied in depth since the late 1940s, based on simple models that neglect the strength and compressibility of the metal liner. Although attempts have been made to improve these models, simplifying assumptions limit the understanding of how the material properties affect the jet formation. With a wide range of material and strength models available for simulation, a validation study was necessary to guide code users in choosing models for shaped charge simulations. Using PAGOSA, a finite-volume Eulerian hydrocode designed to model hypervelocity materials and strong shock waves developed by Los Alamos National Laboratory, and experimental data, we investigated the effects of various equations of state and material strength models on jet formation and penetration of a steel target. Comparing PAGOSA simulations against modern experimental data, we analyzed the strengths and weaknesses of available computational models. LA-UR-16-25639 Los Alamos National Laboratory.
Volumetric flow rate in simulations of microfluidic devices+
NASA Astrophysics Data System (ADS)
Kovalčíková, KristÍna; Slavík, Martin; Bachratá, Katarína; Bachratý, Hynek; Bohiniková, Alžbeta
2018-06-01
In this work, we examine the volumetric flow rate of microfluidic devices. The volumetric flow rate is a parameter which is necessary to correctly set up a simulation of a real device and to check the conformity of a simulation and a laboratory experiments [1]. Instead of defining the volumetric rate at the beginning as a simulation parameter, a parameter of external force is set. The proposed hypothesis is that for a fixed set of other parameters (topology, viscosity of the liquid, …) the volumetric flow rate is linearly dependent on external force in typical ranges of fluid velocity used in our simulations. To confirm this linearity hypothesis and to find numerical limits of this approach, we test several values of the external force parameter. The tests are designed for three different topologies of simulation box and for various haematocrits. The topologies of the microfluidic devices are inspired by existing laboratory experiments [3 - 6]. The linear relationship between the external force and the volumetric flow rate is verified in orders of magnitudes similar to the values obtained from laboratory experiments. Supported by the Slovak Research and Development Agency under the contract No. APVV-15-0751 and by the Ministry of Education, Science, Research and Sport of the Slovak Republic under the contract No. VEGA 1/0643/17.
Investigation related to hydrogen isotopes separation by cryogenic distillation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bornea, A.; Zamfirache, M.; Stefanescu, I.
2008-07-15
Research conducted in the last fifty years has shown that one of the most efficient techniques of removing tritium from the heavy water used as moderator and coolant in CANDU reactors (as that operated at Cernavoda (Romania)) is hydrogen cryogenic distillation. Designing and implementing the concept of cryogenic distillation columns require experiments to be conducted as well as computer simulations. Particularly, computer simulations are of great importance when designing and evaluating the performances of a column or a series of columns. Experimental data collected from laboratory work will be used as input for computer simulations run at larger scale (formore » The Pilot Plant for Tritium and Deuterium Separation) in order to increase the confidence in the simulated results. Studies carried out were focused on the following: - Quantitative analyses of important parameters such as the number of theoretical plates, inlet area, reflux flow, flow-rates extraction, working pressure, etc. - Columns connected in series in such a way to fulfil the separation requirements. Experiments were carried out on a laboratory-scale installation to investigate the performance of contact elements with continuous packing. The packing was manufactured in our institute. (authors)« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ebrahimi, Fatima
2014-07-31
Large-scale magnetic fields have been observed in widely different types of astrophysical objects. These magnetic fields are believed to be caused by the so-called dynamo effect. Could a large-scale magnetic field grow out of turbulence (i.e. the alpha dynamo effect)? How could the topological properties and the complexity of magnetic field as a global quantity, the so called magnetic helicity, be important in the dynamo effect? In addition to understanding the dynamo mechanism in astrophysical accretion disks, anomalous angular momentum transport has also been a longstanding problem in accretion disks and laboratory plasmas. To investigate both dynamo and momentum transport,more » we have performed both numerical modeling of laboratory experiments that are intended to simulate nature and modeling of configurations with direct relevance to astrophysical disks. Our simulations use fluid approximations (Magnetohydrodynamics - MHD model), where plasma is treated as a single fluid, or two fluids, in the presence of electromagnetic forces. Our major physics objective is to study the possibility of magnetic field generation (so called MRI small-scale and large-scale dynamos) and its role in Magneto-rotational Instability (MRI) saturation through nonlinear simulations in both MHD and Hall regimes.« less
Secomb, Jacinta; McKenna, Lisa; Smith, Colleen
2012-12-01
To provide evidence on the effectiveness of simulation activities on the clinical decision-making abilities of undergraduate nursing students. Based on previous research, it was hypothesised that the higher the cognitive score, the greater the ability a nursing student would have to make informed valid decisions in their clinical practice. Globally, simulation is being espoused as an education method that increases the competence of health professionals. At present, there is very little evidence to support current investment in time and resources. Following ethical approval, fifty-eight third-year undergraduate nursing students were randomised in a pretest-post-test group-parallel controlled trial. The learning environment preferences (LEP) inventory was used to test cognitive abilities in order to refute the null hypothesis that activities in computer-based simulated learning environments have a negative effect on cognitive abilities when compared with activities in skills laboratory simulated learning environments. There was no significant difference in cognitive development following two cycles of simulation activities. Therefore, it is reasonable to assume that two simulation tasks, either computer-based or laboratory-based, have no effect on an undergraduate student's ability to make clinical decisions in practice. However, there was a significant finding for non-English first-language students, which requires further investigation. More longitudinal studies that quantify the education effects of simulation on the cognitive, affective and psychomotor attributes of health science students and professionals from both English-speaking and non-English-speaking backgrounds are urgently required. It is also recommended that to achieve increased participant numbers and prevent non-participation owing to absenteeism, further studies need to be imbedded directly into curricula. This investigation confirms the effect of simulation activities on real-life clinical practice, and the comparative learning benefits with traditional clinical practice and university education remain unknown. © 2012 Blackwell Publishing Ltd.
Numerical simulations of stripping effects in high-intensity hydrogen ion linacs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carneiro, J.-P.; /Fermilab; Mustapha, B.
2008-12-01
Numerical simulations of H{sup -} stripping losses from blackbody radiation, electromagnetic fields, and residual gas have been implemented into the beam dynamics code TRACK. Estimates of the stripping losses along two high-intensity H{sup -} linacs are presented: the Spallation Neutron Source linac currently being operated at Oak Ridge National Laboratory and an 8 GeV superconducting linac currently being designed at Fermi National Accelerator Laboratory.
2015-05-12
The Fuel Burner Rig is a test laboratory at NASA Glenn, which subjects new jet engine materials, treated with protective coatings, to the hostile, high temperature, high velocity environment found inside aircraft turbine engines. These samples face 200-mile per hour flames to simulate the temperatures of aircraft engines in flight. The rig can also simulate aircraft carrier and dusty desert operations where salt and sand can greatly reduce engine life and performance.
Computer Series, 17: Bits and Pieces, 5.
ERIC Educational Resources Information Center
Moore, John W., Ed.
1981-01-01
Contains short descriptions of computer programs or hardware that simulate laboratory instruments or results of kinetics experiments, including ones that include experiment error, numerical simulation, first-order kinetic mechanisms, a game for decisionmaking, and simulated mass spectrophotometers. (CS)
Ortega, José Marcos; Esteban, María Dolores; Sánchez, Isidro; Climent, Miguel Ángel
2017-10-31
Nowadays, cement manufacture is one of the most polluting worldwide industrial sectors. In order to reduce its CO₂ emissions, the clinker replacement by ground granulated blast-furnace slag and fly ash is becoming increasingly common. Both additions are well-studied when the hardening conditions of cementitious materials are optimum. Therefore, the main objective of this research was to study the short-term effects of exposure, to both laboratory simulated and real in situ Mediterranean climate environments, on the microstructure and durability-related properties of mortars made using commercial slag and fly ash cements, as well as ordinary Portland cement. The real in situ condition consisted of placing the samples at approximately 100 m away from the Mediterranean Sea. The microstructure was analysed using mercury intrusion porosimetry. The effective porosity, the capillary suction coefficient and the non-steady state chloride migration coefficient were also studied. In view of the results obtained, the non-optimum laboratory simulated Mediterranean environment was a good approach to the real in situ one. Finally, mortars prepared using sustainable cements with slag and fly ash exposed to both Mediterranean climate environments, showed adequate service properties in the short-term (90 days), similar to or even better than those in mortars made with ordinary Portland cement.
Approaches to evaluating weathering effects on release of ...
Increased production and use of engineered nanomaterials (ENMs) over the past decade has increased the potential for the transport and release of these materials into the environment. Here we present results of two separate studies designed to simulate the effects of weathering on the potential release of multiwalled carbon nanotubes (MWCNTs) from polyamide or epoxy composites, and nanosilica from composites with low-density polyethylene (LOPE) with added pro-oxidant. With these weathering-resistant ENMs, the release was primarily driven by degradation of the polymer matrix. The MWCNT-polymer composites were investigated in a pilot inter-laboratory study to simulate the effects of weathering on the potential release of multiwalled carbon nanotubes (MWCNTs) from their composites with two polymers. Wafers of MWCNTs in epoxy and polyamide nanocomposi tes were exposed in four laboratories in the US and Europe under carefully controlled conditions to cycles of simulated sunlight and rainfall over a 2000-hour period. Particles released upon submersion of the weathered wafers in the leaching fluid described in EPA Method 1311 were analyzed by Transmission Electron Microscopy (TEM), Inductively Coupled Plasma- Mass Spectrometry (ICP-MS), and Ultraviolet-Visible Spectroscopy (UV-Vis). Rates ofrelease of MWCNTS determined by ICP-MS (Co associatedwith MWCNTS) and UY-Vis agreed within a factor of two. Other weathering studies of nanosilica-LDPE composites were conducted usi
Galactic Cosmic Ray Simulation at the NASA Space Radiation Laboratory
NASA Technical Reports Server (NTRS)
Norbury, John W.; Slaba, Tony C.; Rusek, Adam
2015-01-01
The external Galactic Cosmic Ray (GCR) spectrum is significantly modified when it passes through spacecraft shielding and astronauts. One approach for simulating the GCR space radiation environment at ground based accelerators would use the modified spectrum, rather than the external spectrum, in the accelerator beams impinging on biological targets. Two recent workshops have studied such GCR simulation. The first workshop was held at NASA Langley Research Center in October 2014. The second workshop was held at the NASA Space Radiation Investigators' workshop in Galveston, Texas in January 2015. The results of these workshops will be discussed in this paper.
Space Shuttle Avionics: a Redundant IMU On-Board Checkout and Redundancy Management System
NASA Technical Reports Server (NTRS)
Mckern, R. A.; Brown, D. G.; Dove, D. W.; Gilmore, J. P.; Landey, M. E.; Musoff, H.; Amand, J. S.; Vincent, K. T., Jr.
1972-01-01
A failure detection and isolation philosophy applicable to multiple off-the-shelf gimbaled IMUs are discussed. The equations developed are implemented and evaluated with actual shuttle trajectory simulations. The results of these simulations are presented for both powered and unpowered flight phases and at operational levels of four, three, and two IMUs. A multiple system checkout philosophy is developed and simulation results presented. The final task develops a laboratory test plan and defines the hardware and software requirements to implement an actual multiple system and evaluate the interim study results for space shuttle application.
Laboratory simulation of field-aligned currents
NASA Technical Reports Server (NTRS)
Wessel, Frank J.; Rostoker, Norman
1993-01-01
A summary of progress during the period Apr. 1992 to Mar. 1993 is provided. Objectives of the research are (1) to simulate, via laboratory experiments, the three terms of the field-aligned current equation; (2) to simulate auroral-arc formation processes by configuring the boundary conditions of the experimental chamber and plasma parameters to produce highly localized return currents at the end of a field-aligned current system; and (3) to extrapolate these results, using theoretical and computational techniques, to the problem of magnetospheric-ionospheric coupling and to compare them with published literature signatures of auroral-arc phenomena.
Performance characteristics of three-phase induction motors
NASA Technical Reports Server (NTRS)
Wood, M. E.
1977-01-01
An investigation into the characteristics of three phase, 400 Hz, induction motors of the general type used on aircraft and spacecraft is summarized. Results of laboratory tests are presented and compared with results from a computer program. Representative motors were both tested and simulated under nominal conditions as well as off nominal conditions of temperature, frequency, voltage magnitude, and voltage balance. Good correlation was achieved between simulated and laboratory results. The primary purpose of the program was to verify the simulation accuracy of the computer program, which in turn will be used as an analytical tool to support the shuttle orbiter.
Conceptual Design and Neutronics Analyses of a Fusion Reactor Blanket Simulation Facility
1986-01-01
Laboratory (LLL) ORNL Oak Ridge National Laboratory PPPL Princeton Plasma Physics Laboratory RSIC Reactor Shielding Information Center (at ORNL) SS...Module (LBM) to be placed in the TFTR at PPPL . Jassby et al. describe the program, including design, manufacturing techniques. neutronics analyses, and
Teaching Cardiovascular Integrations with Computer Laboratories.
ERIC Educational Resources Information Center
Peterson, Nils S.; Campbell, Kenneth B.
1985-01-01
Describes a computer-based instructional unit in cardiovascular physiology. The program (which employs simulated laboratory experimental techniques with a problem-solving format is designed to supplement an animal laboratory and to offer students an integrative approach to physiology through use of microcomputers. Also presents an overview of the…
Funkenbusch, Paul D; Rotella, Mario; Chochlidakis, Konstantinos; Ercoli, Carlo
2016-10-01
Laboratory studies of tooth preparation often involve single values for all variables other than the one being tested. In contrast, in clinical settings, not all variables can be adequately controlled. For example, a new dental rotary cutting instrument may be tested in the laboratory by making a specific cut with a fixed force, but, in clinical practice, the instrument must make different cuts with individual dentists applying different forces. Therefore, the broad applicability of laboratory results to diverse clinical conditions is uncertain and the comparison of effects across studies difficult. The purpose of this in vitro study was to examine the effects of 9 process variables on the dental cutting of rotary cutting instruments used with an electric handpiece and compare them with those of a previous study that used an air-turbine handpiece. The effects of 9 key process variables on the efficiency of a simulated dental cutting operation were measured. A fractional factorial experiment was conducted by using an electric handpiece in a computer-controlled, dedicated testing apparatus to simulate dental cutting procedures with Macor blocks as the cutting substrate. Analysis of variance (ANOVA) was used to assess the statistical significance (α=.05). Four variables (targeted applied load, cut length, diamond grit size, and cut type) consistently produced large, statistically significant effects, whereas 5 variables (rotation per minute, number of cooling ports, rotary cutting instrument diameter, disposability, and water flow rate) produced relatively small, statistically insignificant effects. These results are generally similar to those previously found for an air-turbine handpiece. Regardless of whether an electric or air-turbine handpiece was used, the control exerted by the dentist, simulated in this study by targeting a specific level of applied force, was the single most important factor affecting cutting efficiency. Cutting efficiency was also significantly affected by factors simulating patient/clinical circumstances and hardware choices. These results highlight the greater importance of local clinical conditions (procedure, dentist) in understanding dental cutting as opposed to other hardware-related factors. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.
Funkenbusch, Paul D; Rotella, Mario; Ercoli, Carlo
2015-04-01
Laboratory studies of tooth preparation are often performed under a limited range of conditions involving single values for all variables other than the 1 being tested. In contrast, in clinical settings not all variables can be tightly controlled. For example, a new dental rotary cutting instrument may be tested in the laboratory by making a specific cut with a fixed force, but in clinical practice, the instrument must make different cuts with individual dentists applying a range of different forces. Therefore, the broad applicability of laboratory results to diverse clinical conditions is uncertain and the comparison of effects across studies is difficult. The purpose of this study was to examine the effect of 9 process variables on dental cutting in a single experiment, allowing each variable to be robustly tested over a range of values for the other 8 and permitting a direct comparison of the relative importance of each on the cutting process. The effects of 9 key process variables on the efficiency of a simulated dental cutting operation were measured. A fractional factorial experiment was conducted by using a computer-controlled, dedicated testing apparatus to simulate dental cutting procedures and Macor blocks as the cutting substrate. Analysis of Variance (ANOVA) was used to judge the statistical significance (α=.05). Five variables consistently produced large, statistically significant effects (target applied load, cut length, starting rpm, diamond grit size, and cut type), while 4 variables produced relatively small, statistically insignificant effects (number of cooling ports, rotary cutting instrument diameter, disposability, and water flow rate). The control exerted by the dentist, simulated in this study by targeting a specific level of applied force, was the single most important factor affecting cutting efficiency. Cutting efficiency was also significantly affected by factors simulating patient/clinical circumstances as well as hardware choices. These results highlight the importance of local clinical conditions (procedure, dentist) in understanding dental cutting procedures and in designing adequate experimental methodologies for future studies. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.
SECONDARY ORGANIC AEROSOL FORMATION FROM THE IRRADIATION OF SIMULATED AUTOMOBILE EXHAUST
A laboratory study was conducted to evaluate the potential for secondary organic aerosol formation from emissions from automotive exhaust. The goal was to determine to what extent photochemical oxidation products of these hydrocarbons contribute to secondary organic aerosol (SO...
1991-05-01
Greenberg and B. Lubachevsky (AT& T, Bell Laboratories). We have developed algorithms suitable for simulating a general class of stack replacement policy al...systems of conservation laws. Finally, we began to study various edge detectors based on the (truncated) Hilbert trans- form, in the context of spectral
Evaluation of Three Instructional Methods for Teaching General Chemistry.
ERIC Educational Resources Information Center
Jackman, Lance E.; And Others
1987-01-01
Reports on a study designed to determine the relative effectiveness of different instructional approaches on chemistry laboratory achievement. Investigated differences in achievement in spectrophotometry among college freshmen who received either traditional, learning cycle, or computer simulation instruction. Results indicated that students…
SIMULATED ROADWAY EXPOSURE ATMOSPHERES FOR LABORATORY ANIMAL AND HUMAN STUDIES
We will elucidate the important characteristics that define toxicity resulting from roadway emissions and their interaction with background air. We expect that fresh whole exhaust containing ultrafine particles and vapor will confer the most potent atmosphere. These results wi...
Modeling, simulation, and analysis at Sandia National Laboratories for health care systems
NASA Astrophysics Data System (ADS)
Polito, Joseph
1994-12-01
Modeling, Simulation, and Analysis are special competencies of the Department of Energy (DOE) National Laboratories which have been developed and refined through years of national defense work. Today, many of these skills are being applied to the problem of understanding the performance of medical devices and treatments. At Sandia National Laboratories we are developing models at all three levels of health care delivery: (1) phenomenology models for Observation and Test, (2) model-based outcomes simulations for Diagnosis and Prescription, and (3) model-based design and control simulations for the Administration of Treatment. A sampling of specific applications include non-invasive sensors for blood glucose, ultrasonic scanning for development of prosthetics, automated breast cancer diagnosis, laser burn debridement, surgical staple deformation, minimally invasive control for administration of a photodynamic drug, and human-friendly decision support aids for computer-aided diagnosis. These and other projects are being performed at Sandia with support from the DOE and in cooperation with medical research centers and private companies. Our objective is to leverage government engineering, modeling, and simulation skills with the biotechnical expertise of the health care community to create a more knowledge-rich environment for decision making and treatment.
Setterbo, Jacob J.; Chau, Anh; Fyhrie, Patricia B.; Hubbard, Mont; Upadhyaya, Shrini K.; Symons, Jennifer E.; Stover, Susan M.
2012-01-01
Background Racetrack surface is a risk factor for racehorse injuries and fatalities. Current research indicates that race surface mechanical properties may be influenced by material composition, moisture content, temperature, and maintenance. Race surface mechanical testing in a controlled laboratory setting would allow for objective evaluation of dynamic properties of surface and factors that affect surface behavior. Objective To develop a method for reconstruction of race surfaces in the laboratory and validate the method by comparison with racetrack measurements of dynamic surface properties. Methods Track-testing device (TTD) impact tests were conducted to simulate equine hoof impact on dirt and synthetic race surfaces; tests were performed both in situ (racetrack) and using laboratory reconstructions of harvested surface materials. Clegg Hammer in situ measurements were used to guide surface reconstruction in the laboratory. Dynamic surface properties were compared between in situ and laboratory settings. Relationships between racetrack TTD and Clegg Hammer measurements were analyzed using stepwise multiple linear regression. Results Most dynamic surface property setting differences (racetrack-laboratory) were small relative to surface material type differences (dirt-synthetic). Clegg Hammer measurements were more strongly correlated with TTD measurements on the synthetic surface than the dirt surface. On the dirt surface, Clegg Hammer decelerations were negatively correlated with TTD forces. Conclusions Laboratory reconstruction of racetrack surfaces guided by Clegg Hammer measurements yielded TTD impact measurements similar to in situ values. The negative correlation between TTD and Clegg Hammer measurements confirms the importance of instrument mass when drawing conclusions from testing results. Lighter impact devices may be less appropriate for assessing dynamic surface properties compared to testing equipment designed to simulate hoof impact (TTD). Potential Relevance Dynamic impact properties of race surfaces can be evaluated in a laboratory setting, allowing for further study of factors affecting surface behavior under controlled conditions. PMID:23227183
NASA Technical Reports Server (NTRS)
1972-01-01
Laboratory simulations of three concepts, based on maximum use of available off-the-shelf hardware elements, are described. The concepts are a stereo-foveal-peripheral TV system with symmetric steroscopic split-image registration and 90 deg counter rotation; a computer assisted model control system termed the trajectory following control system; and active manipulator damping. It is concluded that the feasibility of these concepts is established.
U.S. Army Research Laboratory (ARL) XPairIt Simulator for Peptide Docking and Analysis
2014-07-01
results from a case study, docking a short peptide to a small protein. For this test we choose the 1RXZ system from the Protein Data Bank, which...estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data ...core of XPairIt, which additionally contains many data management and organization options, analysis tools, and custom simulation methodology. Two
An Annotated Bibliography of Abstracts on the Use of Simulators in Technical Training
1984-10-01
truing of a bicycle wheel. It matched the design requirements well, was easily studied and controlled in a laboratory, and was felt to be...Article: Experiment. a. Number of groups: 2 b. Description of Groups: (1) Subjects: 27 newly designated first-tour naval aviators (2) Controls : 16 same...experimental group received six sessions in the 2F87F simulator, in accordance with a new syllabus designed for that device, whereas the control group
Dynamic Fracture Simulations of Explosively Loaded Cylinders
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arthur, Carly W.; Goto, D. M.
2015-11-30
This report documents the modeling results of high explosive experiments investigating dynamic fracture of steel (AerMet® 100 alloy) cylinders. The experiments were conducted at Lawrence Livermore National Laboratory (LLNL) during 2007 to 2008 [10]. A principal objective of this study was to gain an understanding of dynamic material failure through the analysis of hydrodynamic computer code simulations. Two-dimensional and three-dimensional computational cylinder models were analyzed using the ALE3D multi-physics computer code.
In a recently completed test program, bench-scale laboratory studies at Arizona State University (ASU) in Tempe, AZ, and pilot-scale studies in a simulated field test situation at Zentox Corp in Ocala, FL, were performed to evaluate the integration of gas-solid ultraviolet (UV) p...
Moore, M H; Hudson, R L; Gerakines, P A
2001-03-15
Infrared (IR) studies of laboratory ices can provide information on the evolution of cosmic-type ices as a function of different simulated space environments involving thermal, ultraviolet (UV), or ion processing. Laboratory radiation experiments can lead to the formation of complex organic molecules. However, because of our lack of knowledge about UV photon and ion fluxes, and exposure lifetimes, it is not certain how well our simulations represent space conditions. Appropriate laboratory experiments are also limited by the absence of knowledge about the composition, density, and temperature of ices in different regions of space. Our current understanding of expected doses due to UV photons and cosmic rays is summarized here, along with an inventory of condensed-phase molecules identified on outer solar system surfaces, comets and interstellar grains. Far-IR spectra of thermally cycled H2O are discussed since these results reflect the dramatic difference between the amorphous and crystalline phases of H2O ice, the most dominant condensed-phase molecule in cosmic ices. A comparison of mid-IR spectra of products in proton-irradiated and UV-photolyzed ices shows that few differences are observed for these two forms of processing for the simple binary mixtures studied to date. IR identification of radiation products and experiments to determine production rates of new molecules in ices during processing are discussed. A new technique for measuring intrinsic IR band strengths of several unstable molecules is presented. An example of our laboratory results applied to Europa observations is included.
Interior of Vacuum Tank at the Electric Propulsion Laboratory
1961-08-21
Interior of the 20-foot diameter vacuum tank at the NASA Lewis Research Center’s Electric Propulsion Laboratory. Lewis researchers had been studying different electric rocket propulsion methods since the mid-1950s. Harold Kaufman created the first successful ion engine, the electron bombardment ion engine, in the early 1960s. These engines used electric power to create and accelerate small particles of propellant material to high exhaust velocities. Electric engines have a very small thrust, but can operate for long periods of time. The ion engines are often clustered together to provide higher levels of thrust. The Electric Propulsion Laboratory, which began operation in 1961, contained two large vacuum tanks capable of simulating a space environment. The tanks were designed especially for testing ion and plasma thrusters and spacecraft. The larger 25-foot diameter tank included a 10-foot diameter test compartment to test electric thrusters with condensable propellants. The portals along the chamber floor lead to the massive exhauster equipment that pumped out the air to simulate the low pressures found in space.
Conceptual design of Dipole Research Experiment (DREX)
NASA Astrophysics Data System (ADS)
Xiao, Qingmei; Wang, Zhibin; Wang, Xiaogang; Xiao, Chijie; Yang, Xiaoyi; Zheng, Jinxing
2017-03-01
A new terrella-like device for laboratory simulation of inner magnetosphere plasmas, Dipole Research Experiment, is scheduled to be built at the Harbin Institute of Technology (HIT), China, as a major state scientific research facility for space physics studies. It is designed to provide a ground experimental platform to reproduce the inner magnetosphere to simulate the processes of trapping, acceleration, and transport of energetic charged particles restrained in a dipole magnetic field configuration. The scaling relation of hydromagnetism between the laboratory plasma of the device and the geomagnetosphere plasma is applied to resemble geospace processes in the Dipole Research Experiment plasma. Multiple plasma sources, different kinds of coils with specific functions, and advanced diagnostics are designed to be equipped in the facility for multi-functions. The motivation, design criteria for the Dipole Research Experiment experiments and the means applied to generate the plasma of desired parameters in the laboratory are also described. Supported by National Natural Science Foundation of China (Nos. 11505040, 11261140326 and 11405038), China Postdoctoral Science Foundation (Nos. 2016M591518, 2015M570283) and Project Supported by Natural Scientific Research Innovation Foundation in Harbin Institute of Technology (No. 2017008).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xu, Zhijie; Lai, Canhai; Marcy, Peter William
2017-05-01
A challenging problem in designing pilot-scale carbon capture systems is to predict, with uncertainty, the adsorber performance and capture efficiency under various operating conditions where no direct experimental data exist. Motivated by this challenge, we previously proposed a hierarchical framework in which relevant parameters of physical models were sequentially calibrated from different laboratory-scale carbon capture unit (C2U) experiments. Specifically, three models of increasing complexity were identified based on the fundamental physical and chemical processes of the sorbent-based carbon capture technology. Results from the corresponding laboratory experiments were used to statistically calibrate the physical model parameters while quantifying some of theirmore » inherent uncertainty. The parameter distributions obtained from laboratory-scale C2U calibration runs are used in this study to facilitate prediction at a larger scale where no corresponding experimental results are available. In this paper, we first describe the multiphase reactive flow model for a sorbent-based 1-MW carbon capture system then analyze results from an ensemble of simulations with the upscaled model. The simulation results are used to quantify uncertainty regarding the design’s predicted efficiency in carbon capture. In particular, we determine the minimum gas flow rate necessary to achieve 90% capture efficiency with 95% confidence.« less
Laboratory development and testing of spacecraft diagnostics
NASA Astrophysics Data System (ADS)
Amatucci, William; Tejero, Erik; Blackwell, Dave; Walker, Dave; Gatling, George; Enloe, Lon; Gillman, Eric
2017-10-01
The Naval Research Laboratory's Space Chamber experiment is a large-scale laboratory device dedicated to the creation of large-volume plasmas with parameters scaled to realistic space plasmas. Such devices make valuable contributions to the investigation of space plasma phenomena under controlled, reproducible conditions, allowing for the validation of theoretical models being applied to space data. However, in addition to investigations such as plasma wave and instability studies, such devices can also make valuable contributions to the development and testing of space plasma diagnostics. One example is the plasma impedance probe developed at NRL. Originally developed as a laboratory diagnostic, the sensor has now been flown on a sounding rocket, is included on a CubeSat experiment, and will be included on the DoD Space Test Program's STP-H6 experiment on the International Space Station. In this talk, we will describe how the laboratory simulation of space plasmas made this development path possible. Work sponsored by the US Naval Research Laboratory Base Program.
Soong, David T.; Murphy, Elizabeth A.; Straub, Timothy D.; Zeeb, Hannah L.
2016-11-22
Results of a flood-hazard analysis conducted by the U.S. Geological Survey, in cooperation with the Argonne National Laboratory, for four headwater streams within the Argonne National Laboratory property indicate that the 1-percent and 0.2-percent annual exceedance probability floods would cause multiple roads to be overtopped. Results indicate that most of the effects on the infrastructure would be from flooding of Freund Brook. Flooding on the Northeast and Southeast Drainage Ways would be limited to overtopping of one road crossing for each of those streams. The Northwest Drainage Way would be the least affected with flooding expected to occur in open grass or forested areas.The Argonne Site Sustainability Plan outlined the development of hydrologic and hydraulic models and the creation of flood-plain maps of the existing site conditions as a first step in addressing resiliency to possible climate change impacts as required by Executive Order 13653 “Preparing the United States for the Impacts of Climate Change.” The Hydrological Simulation Program-FORTRAN is the hydrologic model used in the study, and the Hydrologic Engineering Center‒River Analysis System (HEC–RAS) is the hydraulic model. The model results were verified by comparing simulated water-surface elevations to observed water-surface elevations measured at a network of five crest-stage gages on the four study streams. The comparison between crest-stage gage and simulated elevations resulted in an average absolute difference of 0.06 feet and a maximum difference of 0.19 feet.In addition to the flood-hazard model development and mapping, a qualitative stream assessment was conducted to evaluate stream channel and substrate conditions in the study reaches. This information can be used to evaluate erosion potential.
Dennis, L.W.; Maciel, G.E.; Hatcher, P.G.; Simoneit, B.R.T.
1982-01-01
Cretaceous black shales from DSDP Leg 41, Site 368 in the Eastern Atlantic Ocean were thermally altered during the Miocene by an intrusive basalt. The sediments overlying and underlying the intrusive body were subjected to high temperatures (up to ~ 500??C) and, as a result, their kerogen was significantly altered. The extent of this alteration has been determined by examination by means of 13C nuclear magnetic resonance, using cross polarization/magic-angle spinning (CP/MAS). Results indicate that the kerogen becomes progressively more aromatic in the vicinity of the intrusive body. Laboratory heating experiments, simulating the thermal effects of the basaltic intrusion, produced similar results on unaltered shale from the drill core. The 13C CP/MAS results appear to provide a good measure of thermal alteration. ?? 1982.
NASA Technical Reports Server (NTRS)
Kaber, David B.; Schutte, Paul C. (Technical Monitor)
2000-01-01
This report has been prepared to closeout a NASA grant to Mississippi State University (MSU) for research into situation awareness (SA) and automation in the advanced commercial aircraft cockpit. The grant was divided into two obligations including $60,000 for the period from May 11, 2000 to December 25, 2000. The information presented in this report summarizes work completed through this obligation. It also details work to be completed with the balance of the current obligation and unobligated funds amounting to $50,043, which are to be granted to North Carolina State University for completion of the research project from July 31, 2000 to May 10, 2001. This research was to involve investigation of a broad spectrum of degrees of automation of complex systems on human-machine performance and SA. The work was to empirically assess the effect of theoretical levels of automation (LOAs) described in a taxonomy developed by Endsley & Kaber (1999) on naive and experienced subject performance and SA in simulated flight tasks. The study was to be conducted in the context of a realistic simulation of aircraft flight control. The objective of this work was to identify LOAs that effectively integrate humans and machines under normal operating conditions and failure modes. In general, the work was to provide insight into the design of automation in the commercial aircraft cockpit. Both laboratory and field investigations were to be conducted. At this point in time, a high-fidelity flight simulator of the McDonald Douglas (MD) 11 aircraft has been completed. The simulator integrates a reconfigurable flight simulator developed by the Georgia Institute of Technology and stand-alone simulations of MD-11 autoflight systems developed at MSU. Use of the simulator has been integrated into a study plan for the laboratory research and it is expected that the simulator will also be used in the field study with actual commercial pilots. In addition to the flight simulator, an electronic version of the Situation Awareness Global Assessment Technique (SAGAT) has been completed for measuring commercial pilot SA in flight tasks. The SAGAT is to be used in both the lab and field studies. Finally, the lab study has been designed and subjects have been recruited for participation in experiments. This study will investigate the effects of five levels of automation, described in Endsley & Kaber's (1999) taxonomy and applied to the MD-11 autoflight system, on private pilot performance and SA in basic flight tasks by using the MD-11 simulator. The field study remains to be planned and executed.
Numerical simulations of quasi-perpendicular collisionless shocks
NASA Technical Reports Server (NTRS)
Goodrich, C. C.
1985-01-01
Numerical simulations of collisionless quasi-perpendicular shock waves are reviewed. The strengths and limitations of these simulations are discussed and their experimental (laboratory and spacecraft) context is given. Recent simulation results are emphasized that, with ISEE bow shock observations, are responsible for recent progress in understanding quasi-steady shock structure.
Effects of Learning Support in Simulation-Based Physics Learning
ERIC Educational Resources Information Center
Chang, Kuo-En; Chen, Yu-Lung; Lin, He-Yan; Sung, Yao-Ting
2008-01-01
This paper describes the effects of learning support on simulation-based learning in three learning models: experiment prompting, a hypothesis menu, and step guidance. A simulation learning system was implemented based on these three models, and the differences between simulation-based learning and traditional laboratory learning were explored in…
NASA Astrophysics Data System (ADS)
Li, Gen; Tang, Chun-An; Liang, Zheng-Zhao
2017-01-01
Multi-scale high-resolution modeling of rock failure process is a powerful means in modern rock mechanics studies to reveal the complex failure mechanism and to evaluate engineering risks. However, multi-scale continuous modeling of rock, from deformation, damage to failure, has raised high requirements on the design, implementation scheme and computation capacity of the numerical software system. This study is aimed at developing the parallel finite element procedure, a parallel rock failure process analysis (RFPA) simulator that is capable of modeling the whole trans-scale failure process of rock. Based on the statistical meso-damage mechanical method, the RFPA simulator is able to construct heterogeneous rock models with multiple mechanical properties, deal with and represent the trans-scale propagation of cracks, in which the stress and strain fields are solved for the damage evolution analysis of representative volume element by the parallel finite element method (FEM) solver. This paper describes the theoretical basis of the approach and provides the details of the parallel implementation on a Windows - Linux interactive platform. A numerical model is built to test the parallel performance of FEM solver. Numerical simulations are then carried out on a laboratory-scale uniaxial compression test, and field-scale net fracture spacing and engineering-scale rock slope examples, respectively. The simulation results indicate that relatively high speedup and computation efficiency can be achieved by the parallel FEM solver with a reasonable boot process. In laboratory-scale simulation, the well-known physical phenomena, such as the macroscopic fracture pattern and stress-strain responses, can be reproduced. In field-scale simulation, the formation process of net fracture spacing from initiation, propagation to saturation can be revealed completely. In engineering-scale simulation, the whole progressive failure process of the rock slope can be well modeled. It is shown that the parallel FE simulator developed in this study is an efficient tool for modeling the whole trans-scale failure process of rock from meso- to engineering-scale.
Developing a Remote Laboratory for Engineering Education
ERIC Educational Resources Information Center
Fabregas, E.; Farias, G.; Dormido-Canto, S.; Dormido, S.; Esquembre, F.
2011-01-01
New information technologies provide great opportunities for education. One such opportunity is the use of remote control laboratories for teaching students about control systems. This paper describes the creation of interactive remote laboratories (RLs). Two main software tools are used: Simulink and Easy Java Simulations (EJS). The first is a…
Evaluation of the Virtual Physiology of Exercise Laboratory Program
ERIC Educational Resources Information Center
Dobson, John L.
2009-01-01
The Virtual Physiology of Exercise Laboratory (VPEL) program was created to simulate the test design, data collection, and analysis phases of selected exercise physiology laboratories. The VPEL program consists of four modules: (1) cardiovascular, (2) maximal O[subscript 2] consumption [Vo[subscript 2max], (3) lactate and ventilatory thresholds,…
NASA Technical Reports Server (NTRS)
Borsky, P. N.
1977-01-01
Residents living in close, middle and distant areas from JFK Airport were included in a field interview and laboratory study. Judgments were made of simulated aircraft noise exposures of comparable community indoor noise levels and mixes of aircraft. Each group of subjects judged the levels of noise typical for its distance area. Four different numbers of flyovers were tested: less than average for each area, the approximate average, the peak number, or worst day, and above peak number. The major findings are: (1) the reported integrated field annoyance is best related to the annoyance reported for the simulated approximate worst day exposure in the laboratory; (2) annoyance is generally less when there are fewer aircraft flyovers, and the subject has less fear of crashes and more favorable attitudes toward airplanes; (3) beliefs in harmful health effects and misfeasance by operators of aircraft are also highly correlated with fear and noise annoyance; (4) in direct retrospective comparisons of number of flights, noise levels and annoyance, subjects more often said the worst day laboratory exposured more like their usual home environments; and (5) subjects do not expect an annoyance-free environment. Half of the subjects can accept an annoyance level of 5 to 6 from a possible annoyance range of 0 to 9, 28% can live with an annoyance intensity of 7, and only 5% can accept the top scores of 8 to 9.
A suite of benchmark and challenge problems for enhanced geothermal systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
White, Mark; Fu, Pengcheng; McClure, Mark
A diverse suite of numerical simulators is currently being applied to predict or understand the performance of enhanced geothermal systems (EGS). To build confidence and identify critical development needs for these analytical tools, the United States Department of Energy, Geothermal Technologies Office sponsored a Code Comparison Study (GTO-CCS), with participants from universities, industry, and national laboratories. A principal objective for the study was to create a community forum for improvement and verification of numerical simulators for EGS modeling. Teams participating in the study were those representing U.S. national laboratories, universities, and industries, and each team brought unique numerical simulation capabilitiesmore » to bear on the problems. Two classes of problems were developed during the study, benchmark problems and challenge problems. The benchmark problems were structured to test the ability of the collection of numerical simulators to solve various combinations of coupled thermal, hydrologic, geomechanical, and geochemical processes. This class of problems was strictly defined in terms of properties, driving forces, initial conditions, and boundary conditions. The challenge problems were based on the enhanced geothermal systems research conducted at Fenton Hill, near Los Alamos, New Mexico, between 1974 and 1995. The problems involved two phases of research, stimulation, development, and circulation in two separate reservoirs. The challenge problems had specific questions to be answered via numerical simulation in three topical areas: 1) reservoir creation/stimulation, 2) reactive and passive transport, and 3) thermal recovery. Whereas the benchmark class of problems were designed to test capabilities for modeling coupled processes under strictly specified conditions, the stated objective for the challenge class of problems was to demonstrate what new understanding of the Fenton Hill experiments could be realized via the application of modern numerical simulation tools by recognized expert practitioners. We present the suite of benchmark and challenge problems developed for the GTO-CCS, providing problem descriptions and sample solutions.« less
Haji, Faizal A; Da Silva, Celina; Daigle, Delton T; Dubrowski, Adam
2014-08-01
Presently, health care simulation research is largely conducted on a study-by-study basis. Although such "project-based" research generates a plethora of evidence, it can be chaotic and contradictory. A move toward sustained, thematic, theory-based programs of research is necessary to advance knowledge in the field. Recognizing that simulation is a complex intervention, we present a framework for developing research programs in simulation-based education adapted from the Medical Research Council (MRC) guidance. This framework calls for an iterative approach to developing, refining, evaluating, and implementing simulation interventions. The adapted framework guidance emphasizes: (1) identification of theory and existing evidence; (2) modeling and piloting interventions to clarify active ingredients and identify mechanisms linking the context, intervention, and outcomes; and (3) evaluation of intervention processes and outcomes in both the laboratory and real-world setting. The proposed framework will aid simulation researchers in developing more robust interventions that optimize simulation-based education and advance our understanding of simulation pedagogy.
High performance computing in biology: multimillion atom simulations of nanoscale systems
Sanbonmatsu, K. Y.; Tung, C.-S.
2007-01-01
Computational methods have been used in biology for sequence analysis (bioinformatics), all-atom simulation (molecular dynamics and quantum calculations), and more recently for modeling biological networks (systems biology). Of these three techniques, all-atom simulation is currently the most computationally demanding, in terms of compute load, communication speed, and memory load. Breakthroughs in electrostatic force calculation and dynamic load balancing have enabled molecular dynamics simulations of large biomolecular complexes. Here, we report simulation results for the ribosome, using approximately 2.64 million atoms, the largest all-atom biomolecular simulation published to date. Several other nanoscale systems with different numbers of atoms were studied to measure the performance of the NAMD molecular dynamics simulation program on the Los Alamos National Laboratory Q Machine. We demonstrate that multimillion atom systems represent a 'sweet spot' for the NAMD code on large supercomputers. NAMD displays an unprecedented 85% parallel scaling efficiency for the ribosome system on 1024 CPUs. We also review recent targeted molecular dynamics simulations of the ribosome that prove useful for studying conformational changes of this large biomolecular complex in atomic detail. PMID:17187988
Parachute Models Used in the Mars Science Laboratory Entry, Descent, and Landing Simulation
NASA Technical Reports Server (NTRS)
Cruz, Juan R.; Way, David W.; Shidner, Jeremy D.; Davis, Jody L.; Powell, Richard W.; Kipp, Devin M.; Adams, Douglas S.; Witkowski, Al; Kandis, Mike
2013-01-01
An end-to-end simulation of the Mars Science Laboratory (MSL) entry, descent, and landing (EDL) sequence was created at the NASA Langley Research Center using the Program to Optimize Simulated Trajectories II (POST2). This simulation is capable of providing numerous MSL system and flight software responses, including Monte Carlo-derived statistics of these responses. The MSL POST2 simulation includes models of EDL system elements, including those related to the parachute system. Among these there are models for the parachute geometry, mass properties, deployment, inflation, opening force, area oscillations, aerodynamic coefficients, apparent mass, interaction with the main landing engines, and off-loading. These models were kept as simple as possible, considering the overall objectives of the simulation. The main purpose of this paper is to describe these parachute system models to the extent necessary to understand how they work and some of their limitations. A list of lessons learned during the development of the models and simulation is provided. Future improvements to the parachute system models are proposed.
Reflectivity of the atmosphere-inhomogeneous surfaces system Laboratory simulation
NASA Technical Reports Server (NTRS)
Mekler, Y.; Kaufman, Y. J.; Fraser, R. S.
1984-01-01
Theoretical two- and three-dimensional solutions of the radiative transfer equation have been applied to the earth-atmosphere system. Such solutions have not been verified experimentally. A laboratory experiment simulates such a system to test the theory. The atmosphere was simulated by latex spheres suspended in water and the ground by a nonuniform surface, half white and half black. A stable radiation source provided uniform illumination over the hydrosol. The upward radiance along a line orthogonal to the boundary of the two-halves field was recorded for different amounts of the hydrosol. The simulation is a well-defined radiative transfer experiment to test radiative transfer models involving nonuniform surfaces. Good agreement is obtained between the measured and theoretical results.
Design and test of a simulation system for autonomous optic-navigated planetary landing
NASA Astrophysics Data System (ADS)
Cai, Sheng; Yin, Yanhe; Liu, Yanjun; He, Fengyun
2018-02-01
In this paper, a simulation system based on commercial projector is proposed to test the optical navigation algorithms for autonomous planetary landing in laboratorial scenarios. The design work of optics, mechanics and synchronization control are carried out. Furthermore, the whole simulation system is set up and tested. Through the calibration of the system, two main problems, synchronization between the projector and CCD and pixel-level shifting caused by the low repeatability of DMD used in the projector, are settled. The experimental result shows that the RMS errors of pitch, yaw and roll angles are 0.78', 0.48', and 2.95' compared with the theoretical calculation, which can fulfill the requirement of experimental simulation for planetary landing in laboratory.
Effect of simulation on the ability of first year nursing students to learn vital signs.
Eyikara, Evrim; Baykara, Zehra Göçmen
2018-01-01
The acquisition of cognitive, affective and psychomotor knowledge and skills are required in nursing, made possible via an interactive teaching method, such as simulation. This study conducted to identify the impact of simulation on first-year nursing students' ability to learn vital signs. A convenience sample of 90 first-year nursing students enrolled at a University, Ankara, in 2014-2015. Ninety students enrolled for lessons on the "Fundamentals of Nursing" were identified using a simple random sampling method. The students were taught vital signs theory via traditional methods. They were grouped into experimental 1, experimental 2 and control group, of 30 students each. Students in the experimental 1 group attended sessions on simulation and those in the experimental 2 group sessions on laboratory work, followed by simulation. The control group were taught via traditional methods and only attended the laboratory work sessions. The students' cognitive knowledge acquisition was evaluated using a knowledge test before and after the lessons. The ability to measure vital signs in adults (healthy ones and patients) was evaluated using a skill control list. A statistically significant difference was not observed between the groups in terms of the average pre-test scores on knowledge (p>0.050). Groups exposed to simulation obtained statistically significantly higher scores than the control group in post-test knowledge (p<0.050). The ability of the groups exposed to simulation to measure vital signs in healthy adults and patients was more successful than that the control group (p<0.050). This was statistically significant. Simulation had a positive effect on the ability of nursing students to measure vital signs. Thus, simulation should be included in the mainstream curriculum in order to effectively impart nursing knowledge and skills. Copyright © 2017 Elsevier Ltd. All rights reserved.
Effect of Harsh or Mild Extraction of Soil on Pesticide Leaching to Groundwater.
Boesten, Jos J T I
2016-07-01
Assessment of leaching to groundwater is an important aspect of pesticide risk assessment. The first leaching tier usually consists of simulations with leaching scenarios based on pesticide-soil properties derived from laboratory studies. Because the extractability of pesticide residues in such studies decreases with time, the harshness of the extraction method influences these pesticide-soil properties. This study investigates the effect of using a mild or harsh extraction method on simulated leaching to groundwater with consideration of substances with a range of half-lives and organic matter sorption coefficient values for selected leaching scenarios. The model for linking the concentrations of the mild and the harsh systems was based on laboratory studies with two pesticides and a Dutch sandy soil and was tested against Canadian field studies with atrazine (6-chloro-2-ethyl-4-isopropyl-1,3,5-triazine-2,4-diamine). The degradation rate and the aged-sorption parameters of each "mild" soil-substance system were derived from a hypothetical laboratory incubation study using prescribed parameter values for the corresponding "harsh" soil-substance system. Simulations were performed for three European leaching scenarios (United Kingdom, France, Portugal). For the best-guess parameter set, the leaching concentrations of the harsh system were approximately equal to those of the mild system at leaching concentrations greater than 1 μg L and were at most approximately a factor of two higher than those of the mild systems at mild leaching concentrations between 0.01 and 0.1 μg L. However, an extreme parameter set led to harsh leaching concentrations that were at most approximately 10 times higher than the mild leaching concentrations at levels between 0.01 and 0.1 μg L. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
NASA Astrophysics Data System (ADS)
Quinn, J. D.; Larour, E. Y.; Cheng, D. L. C.; Halkides, D. J.
2016-12-01
The Virtual Earth System Laboratory (VESL) is a Web-based tool, under development at the Jet Propulsion Laboratory and UC Irvine, for the visualization of Earth System data and process simulations. It contains features geared toward a range of applications, spanning research and outreach. It offers an intuitive user interface, in which model inputs are changed using sliders and other interactive components. Current capabilities include simulation of polar ice sheet responses to climate forcing, based on NASA's Ice Sheet System Model (ISSM). We believe that the visualization of data is most effective when tailored to the target audience, and that many of the best practices for modern Web design/development can be applied directly to the visualization of data: use of negative space, color schemes, typography, accessibility standards, tooltips, etc cetera. We present our prototype website, and invite input from potential users, including researchers, educators, and students.
NASA Technical Reports Server (NTRS)
Jennings, Esther H.; Nguyen, Sam P.; Wang, Shin-Ywan; Woo, Simon S.
2008-01-01
NASA's planned Lunar missions will involve multiple NASA centers where each participating center has a specific role and specialization. In this vision, the Constellation program (CxP)'s Distributed System Integration Laboratories (DSIL) architecture consist of multiple System Integration Labs (SILs), with simulators, emulators, testlabs and control centers interacting with each other over a broadband network to perform test and verification for mission scenarios. To support the end-to-end simulation and emulation effort of NASA' exploration initiatives, different NASA centers are interconnected to participate in distributed simulations. Currently, DSIL has interconnections among the following NASA centers: Johnson Space Center (JSC), Kennedy Space Center (KSC), Marshall Space Flight Center (MSFC) and Jet Propulsion Laboratory (JPL). Through interconnections and interactions among different NASA centers, critical resources and data can be shared, while independent simulations can be performed simultaneously at different NASA locations, to effectively utilize the simulation and emulation capabilities at each center. Furthermore, the development of DSIL can maximally leverage the existing project simulation and testing plans. In this work, we describe the specific role and development activities at JPL for Space Communications and Navigation Network (SCaN) simulator using the Multi-mission Advanced Communications Hybrid Environment for Test and Evaluation (MACHETE) tool to simulate communications effects among mission assets. Using MACHETE, different space network configurations among spacecrafts and ground systems of various parameter sets can be simulated. Data that is necessary for tracking, navigation, and guidance of spacecrafts such as Crew Exploration Vehicle (CEV), Crew Launch Vehicle (CLV), and Lunar Relay Satellite (LRS) and orbit calculation data are disseminated to different NASA centers and updated periodically using the High Level Architecture (HLA). In addition, the performance of DSIL under different traffic loads with different mix of data and priorities are evaluated.
Laboratory Measurements of the 940, 1130, and 1370 nm Water Vapor Absorption Band Profiles
NASA Technical Reports Server (NTRS)
Giver, Lawrence P.; Gore, Warren J.; Pilewskie, P.; Freedman, R. S.; Chackerian, C., Jr.; Varanasi, P.
2001-01-01
We have used the solar spectral flux radiometer (SSFR) flight instrument with the Ames 25 meter base-path White cell to obtain about 20 moderate resolution (8 nm) pure water vapor spectra from 650 to 1650 nm, with absorbing paths from 806 to 1506 meters and pressures up to 14 torr. We also obtained a set at 806 meters with several different air-broadening pressures. Model simulations were made for the 940, 1130, and 1370 nm absorption bands for some of these laboratory conditions using the Rothman, et al HITRAN-2000 linelist. This new compilation of HITRAN includes new intensity measurements for the 940 nm region. We compared simulations for our spectra of this band using HITRAN-2000 with simulations using the prior HITRAN-1996. The simulations of the 1130 nm band show about 10% less absorption than we measured. There is some evidence that the total intensity of this band is about 38% stronger than the sum of the HITRAN line intensities in this region. In our laboratory conditions the absorption depends approximately on the square root of the intensity. Thus, our measurements agree that the band is stronger than tabulated in HITRAN, but by about 20%, substantially less than the published value. Significant differences have been shown between Doppler-limited resolution spectra of the 1370 nm band obtained at the Pacific Northwest National Laboratory and HITRAN simulations. Additional new intensity measurements in this region are continuing to be made. We expect the simulations of our SSFR lab data of this band will show the relative importance of improving the HITRAN line intensities of this band for atmospheric measurements.
Accuracy of finite-difference modeling of seismic waves : Simulation versus laboratory measurements
NASA Astrophysics Data System (ADS)
Arntsen, B.
2017-12-01
The finite-difference technique for numerical modeling of seismic waves is still important and for some areas extensively used.For exploration purposes is finite-difference simulation at the core of both traditional imaging techniques such as reverse-time migration and more elaborate Full-Waveform Inversion techniques.The accuracy and fidelity of finite-difference simulation of seismic waves are hard to quantify and meaningfully error analysis is really onlyeasily available for simplistic media. A possible alternative to theoretical error analysis is provided by comparing finite-difference simulated data with laboratory data created using a scale model. The advantage of this approach is the accurate knowledge of the model, within measurement precision, and the location of sources and receivers.We use a model made of PVC immersed in water and containing horizontal and tilted interfaces together with several spherical objects to generateultrasonic pressure reflection measurements. The physical dimensions of the model is of the order of a meter, which after scaling represents a model with dimensions of the order of 10 kilometer and frequencies in the range of one to thirty hertz.We find that for plane horizontal interfaces the laboratory data can be reproduced by the finite-difference scheme with relatively small error, but for steeply tilted interfaces the error increases. For spherical interfaces the discrepancy between laboratory data and simulated data is sometimes much more severe, to the extent that it is not possible to simulate reflections from parts of highly curved bodies. The results are important in view of the fact that finite-difference modeling is often at the core of imaging and inversion algorithms tackling complicatedgeological areas with highly curved interfaces.
Brooks, Myron H.; Schroder, LeRoy J.; Willoughby, Timothy C.
1987-01-01
Four laboratories involved in the routine analysis of wet-deposition samples participated in an interlaboratory comparison program managed by the U.S. Geological Survey. The four participants were: Illinois State Water Survey central analytical laboratory in Champaign, Illinois; U.S. Geological Survey national water-quality laboratories in Atlanta, Georgia, and Denver, Colorado; and Inland Waters Directorate national water-quality laboratory in Burlington, Ontario, Canada. Analyses of interlaboratory samples performed by the four laboratories from October 1983 through December 1984 were compared.Participating laboratories analyzed three types of interlaboratory samples--natural wet deposition, simulated wet deposition, and deionized water--for pH and specific conductance, and for dissolved calcium, magnesium, sodium, sodium, potassium, chloride, sulfate, nitrate, ammonium, and orthophosphate. Natural wet-deposition samples were aliquots of actual wet-deposition samples. Analyses of these samples by the four laboratories were compared using analysis of variance. Test results indicated that pH, calcium, nitrate, and ammonium results were not directly comparable among the four laboratories. Statistically significant differences between laboratory results probably only were meaningful for analyses of dissolved calcium. Simulated wet-deposition samples with known analyte concentrations were used to test each laboratory for analyte bias. Laboratory analyses of calcium, magnesium, sodium, potassium, chloride, sulfate, and nitrate were not significantly different from the known concentrations of these analytes when tested using analysis of variance. Deionized-water samples were used to test each laboratory for reporting of false positive values. The Illinois State Water Survey Laboratory reported the smallest percentage of false positive values for most analytes. Analyte precision was estimated for each laboratory from results of replicate measurements. In general, the Illinois State Water Survey laboratory achieved the greatest precision, whereas the U.S. Geological Survey laboratories achieved the least precision.
NASA Astrophysics Data System (ADS)
Kordilla, Jannes; Noffz, Torsten; Dentz, Marco; Geyer, Tobias; Tartakovsky, Alexandre M.
2017-11-01
In this work, we study gravity-driven flow of water in the presence of air on a synthetic surface intersected by a horizontal fracture and investigate the importance of droplet and rivulet flow modes on the partitioning behavior at the fracture intersection. We present laboratory experiments, three-dimensional smoothed particle hydrodynamics (SPH) simulations using a heavily parallelized code, and a theoretical analysis. The flow-rate-dependent mode switching from droplets to rivulets is observed in experiments and reproduced by the SPH model, and the transition ranges agree in SPH simulations and laboratory experiments. We show that flow modes heavily influence the "bypass" behavior of water flowing along a fracture junction. Flows favoring the formation of droplets exhibit a much stronger bypass capacity compared to rivulet flows, where nearly the whole fluid mass is initially stored within the horizontal fracture. The effect of fluid buffering within the horizontal fracture is presented in terms of dimensionless fracture inflow so that characteristic scaling regimes can be recovered. For both cases (rivulets and droplets), the flow within the horizontal fracture transitions into a Washburn regime until a critical threshold is reached and the bypass efficiency increases. For rivulet flows, the initial filling of the horizontal fracture is described by classical plug flow. Meanwhile, for droplet flows, a size-dependent partitioning behavior is observed, and the filling of the fracture takes longer. For the case of rivulet flow, we provide an analytical solution that demonstrates the existence of classical Washburn flow within the horizontal fracture.
Grierson, Lawrence; Melnyk, Megan; Jowlett, Nathan; Backstein, David; Dubrowski, Adam
2011-01-01
Skills training in simulation laboratories is becoming increasingly common. However, the educational benefit of these laboratories remains unclear. This study examined whether such training enables better performance on the simultaneous execution of technical skill and knowledge retention. Twenty-four novice trainees completed the elliptical excision on baseline testing. Following baseline testing twelve of the novices completed a technical practice (simulation training group) session, while the other twelve did not (control group). One week later, all participants returned for dual-task follow up testing in which they performed the excision while listening to a didactic lesson on the staging and treatment of cutaneous melanoma. The dual-tasking during the post test was standardized, whereby excision sutures 3 and 5 were performed alone (single), and sutures 4 and 6 were performed concurrently with the didactic lecture (dual). Seven additional trainees also participated as controls that were randomized to listen to the didactic lesson alone (knowledge retention alone group). Knowledge retention was assessed by a multiple choice questionnaire (MCQ). Technical performance was evaluated with computer and expert-based measures. Time to complete the performance improved among both groups completing the elliptical excision on follow-up testing (p<0.01). The simulation training group demonstrated superior hand motion performance on simultaneous didactic lesson testing (p<0.01). Novices from the no-training group performed statistically worse while suturing concurrently with the didactic lesson (p<0.01). The pretraining of novices in surgical skills laboratories leads to improved technical performance during periods of increased attention demands.
A review of laboratory and numerical modelling in volcanology
NASA Astrophysics Data System (ADS)
Kavanagh, Janine L.; Engwell, Samantha L.; Martin, Simon A.
2018-04-01
Modelling has been used in the study of volcanic systems for more than 100 years, building upon the approach first applied by Sir James Hall in 1815. Informed by observations of volcanological phenomena in nature, including eye-witness accounts of eruptions, geophysical or geodetic monitoring of active volcanoes, and geological analysis of ancient deposits, laboratory and numerical models have been used to describe and quantify volcanic and magmatic processes that span orders of magnitudes of time and space. We review the use of laboratory and numerical modelling in volcanological research, focussing on sub-surface and eruptive processes including the accretion and evolution of magma chambers, the propagation of sheet intrusions, the development of volcanic flows (lava flows, pyroclastic density currents, and lahars), volcanic plume formation, and ash dispersal. When first introduced into volcanology, laboratory experiments and numerical simulations marked a transition in approach from broadly qualitative to increasingly quantitative research. These methods are now widely used in volcanology to describe the physical and chemical behaviours that govern volcanic and magmatic systems. Creating simplified models of highly dynamical systems enables volcanologists to simulate and potentially predict the nature and impact of future eruptions. These tools have provided significant insights into many aspects of the volcanic plumbing system and eruptive processes. The largest scientific advances in volcanology have come from a multidisciplinary approach, applying developments in diverse fields such as engineering and computer science to study magmatic and volcanic phenomena. A global effort in the integration of laboratory and numerical volcano modelling is now required to tackle key problems in volcanology and points towards the importance of benchmarking exercises and the need for protocols to be developed so that models are routinely tested against real world
data.
Laboratory Studies of Interstellar PAH Analogs
NASA Technical Reports Server (NTRS)
Salama, Farid; DeVincenzi, Donald (Technical Monitor)
2000-01-01
Polycyclic aromatic hydrocarbons (PAHs) are now considered to be an important and ubiquitous component of the organic material in space. PAHs are found in a large variety of extraterrestrial materials such as interplanetary dust particles (IDPs) and meteoritic materials. PAHs are also good candidates to account for the infrared emission bands (UIRs) and the diffuse interstellar optical absorption bands (DIBs) detected in various regions of the interstellar medium. The recent observations made with the Infrared Space Observatory (ISO) have confirmed the ubiquitous nature of the UIR bands and their carriers. PAHs are though to form through chemical reactions in the outflow from carbon-rich stars in a process similar to soot formation. Once injected in the interstellar medium, PAHs are further processed by the interstellar radiation field, interstellar shocks and energetic particles. A major, dedicated, laboratory effort has been undertaken over the past years to measure the physical and chemical characteristics of these complex molecules and their ions under experimental conditions that mimic the interstellar conditions. These measurements require collision-free conditions where the molecules and ions are cold and chemically isolated. The spectroscopy of PAHs under controlled conditions represents an essential diagnostic tool to study the evolution of extraterrestrial PAHs. The Astrochemistry Laboratory program will be discussed through its multiple aspects: objectives, approach and techniques adopted, adaptability to the nature of the problem(s), results and implications for astronomy as well as for molecular spectroscopy. A review of the data generated through laboratory simulations of space environments and the role these data have played in our current understanding of the properties of interstellar PAHs will be presented. The discussion will also introduce the newest generation of laboratory experiments that are currently being developed in order to provide a closer simulation of space environments and a better support to space missions.
EFFECT OF VARYING FLOW REGIMES ON BIOFILM DENSITIES IN A DISTRIBUTION SYSTEM SIMULATOR
Maintenance of a free chlorine residual within water distribution systems is used to reduce the possibility of microbial contamination. However, it has been demonstrated that biofilms within water distribution systems can harbor coliforms. In laboratory scale studies, others have...
This is a site assessment and feasibility study of incineration alternatives at the ACME Solvents Site at Rockford, Illinois. The document contains laboratory results that are reported to simulate incineration conditions but no details on test methods were provided. The d...
Tracer Studies In Laboratory Beach Simulating Tidal Influences
Bioremediation of oil spills on tidally influenced beaches commonly involves the addition of a nutrient solution to the contaminated region of the beach at low tide to stimulate the growth of indigenous oil-degrading bacteria. Maximizing the residentce time of nutrients in the be...
DOT National Transportation Integrated Search
1988-04-01
A laboratory study using bentonite to simulate the montmorillonite component of soils common to Louisiana was undertaken to evaluate the effects of combined lime and fly ash additions on stabilization reactions. Samples containing bentonite (75 weigh...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yamamoto, K.; Mizuno, Y.; Hibino, S.
2006-01-15
Simulations of dusty plasmas were performed using GRAPE-6, a special-purpose computer designed for gravitational N-body problems. The collective behavior of dust particles, which are injected into the plasma, was studied by means of three-dimensional computer simulations. As an example of a dusty plasma simulation, experiments on Coulomb crystals in plasmas are simulated. Formation of a quasi-two-dimensional Coulomb crystal has been observed under typical laboratory conditions. Another example was to simulate movement of dust particles in plasmas under microgravity conditions. Fully three-dimensional spherical structures of dust clouds have been observed. For the simulation of a dusty plasma in microgravity with 3x10{supmore » 4} particles, GRAPE-6 can perform the whole operation 1000 times faster than by using a Pentium 4 1.6 GHz processor.« less
Using a medical simulation center as an electronic health record usability laboratory
Landman, Adam B; Redden, Lisa; Neri, Pamela; Poole, Stephen; Horsky, Jan; Raja, Ali S; Pozner, Charles N; Schiff, Gordon; Poon, Eric G
2014-01-01
Usability testing is increasingly being recognized as a way to increase the usability and safety of health information technology (HIT). Medical simulation centers can serve as testing environments for HIT usability studies. We integrated the quality assurance version of our emergency department (ED) electronic health record (EHR) into our medical simulation center and piloted a clinical care scenario in which emergency medicine resident physicians evaluated a simulated ED patient and documented electronically using the ED EHR. Meticulous planning and close collaboration with expert simulation staff was important for designing test scenarios, pilot testing, and running the sessions. Similarly, working with information systems teams was important for integration of the EHR. Electronic tools are needed to facilitate entry of fictitious clinical results while the simulation scenario is unfolding. EHRs can be successfully integrated into existing simulation centers, which may provide realistic environments for usability testing, training, and evaluation of human–computer interactions. PMID:24249778
Molecular simulation studies on chemical reactivity of methylcyclopentadiene.
Wang, Qingsheng; Zhang, Yingchun; Rogers, William J; Mannan, M Sam
2009-06-15
Molecular simulations are important to predict thermodynamic values for reactive chemicals especially when sufficient experimental data are not available. Methylcyclopentadiene (MCP) is an example of a highly reactive and hazardous compound in the chemical process industry. In this work, chemical reactivity of 2-methylcyclopentadiene, including isomerization, dimerization, and oxidation reactions, is investigated in detail by theoretical computational chemistry methods and empirical thermodynamic-energy correlation. On the basis of molecular simulations, an average value of -15.2 kcal/mol for overall heat of dimerization and -45.6 kcal/mol for overall heat of oxidation were obtained in gaseous phase at 298 K and 1 atm. These molecular simulation studies can provide guidance for the design of safer chemical processes, safer handling of MCP, and also provide useful information for an investigation of the T2 Laboratories explosion on December 19, 2007, in Florida.
Comparison of DAC and MONACO DSMC Codes with Flat Plate Simulation
NASA Technical Reports Server (NTRS)
Padilla, Jose F.
2010-01-01
Various implementations of the direct simulation Monte Carlo (DSMC) method exist in academia, government and industry. By comparing implementations, deficiencies and merits of each can be discovered. This document reports comparisons between DSMC Analysis Code (DAC) and MONACO. DAC is NASA's standard DSMC production code and MONACO is a research DSMC code developed in academia. These codes have various differences; in particular, they employ distinct computational grid definitions. In this study, DAC and MONACO are compared by having each simulate a blunted flat plate wind tunnel test, using an identical volume mesh. Simulation expense and DSMC metrics are compared. In addition, flow results are compared with available laboratory data. Overall, this study revealed that both codes, excluding grid adaptation, performed similarly. For parallel processing, DAC was generally more efficient. As expected, code accuracy was mainly dependent on physical models employed.
Examining System-Wide Impacts of Solar PV Control Systems with a Power Hardware-in-the-Loop Platform
DOE Office of Scientific and Technical Information (OSTI.GOV)
Williams, Tess L.; Fuller, Jason C.; Schneider, Kevin P.
2014-10-11
High penetration levels of distributed solar PV power generation can lead to adverse power quality impacts such as excessive voltage rise, voltage flicker, and reactive power values that result in unacceptable voltage levels. Advanced inverter control schemes have been proposed that have the potential to mitigate many power quality concerns. However, closed-loop control may lead to unintended behavior in deployed systems as complex interactions can occur between numerous operating devices. In order to enable the study of the performance of advanced control schemes in a detailed distribution system environment, a Hardware-in-the-Loop (HIL) platform has been developed. In the HIL system,more » GridLAB-D, a distribution system simulation tool, runs in real-time mode at the Pacific Northwest National Laboratory (PNNL) and supplies power system parameters at a point of common coupling to hardware located at the National Renewable Energy Laboratory (NREL). Hardware inverters interact with grid and PV simulators emulating an operational distribution system and power output from the inverters is measured and sent to PNNL to update the real-time distribution system simulation. The platform is described and initial test cases are presented. The platform is used to study the system-wide impacts and the interactions of controls applied to inverters that are integrated into a simulation of the IEEE 8500-node test feeder, with inverters in either constant power factor control or active volt/VAR control. We demonstrate that this HIL platform is well-suited to the study of advanced inverter controls and their impacts on the power quality of a distribution feeder. Additionally, the results from HIL are used to validate GridLAB-D simulations of advanced inverter controls.« less
Evaluation and Enhancement of Carbon Dioxide Flooding Through Sweep Improvement
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hughes, Richard
2009-09-30
Carbon dioxide displacement is a common improved recovery method applied to light oil reservoirs (30-45{degrees}API). The economic and technical success of CO{sub 2} floods is often limited by poor sweep efficiency or large CO{sub 2} utilization rates. Projected incremental recoveries for CO{sub 2} floods range from 7% to 20% of the original oil in place; however, actual incremental recoveries range from 9% to 15% of the original oil in place, indicating the potential for significant additional recoveries with improved sweep efficiency. This research program was designed to study the effectiveness of carbon dioxide flooding in a mature reservoir to identifymore » and develop methods and strategies to improve oil recovery in carbon dioxide floods. Specifically, the project has focused on relating laboratory, theoretical and simulation studies to actual field performance in a CO{sub 2} flood in an attempt to understand and mitigate problems of areal and vertical sweep efficiency. In this work the focus has been on evaluating the status of existing swept regions of a mature CO{sub 2} flood and developing procedures to improve the design of proposed floods. The Little Creek Field, Mississippi has been studied through laboratory, theoretical, numerical and simulation studies in an attempt to relate performance predictions to historical reservoir performance to determine sweep efficiency, improve the understanding of the reservoir response to CO{sub 2} injection, and develop scaling methodologies to relate laboratory data and simulation results to predicted reservoir behavior. Existing laboratory information from Little Creek was analyzed and an extensive amount of field data was collected. This was merged with an understanding of previous work at Little Creek to generate a detailed simulation study of two portions of the field – the original pilot area and a currently active part of the field. This work was done to try to relate all of this information to an understanding of where the CO{sub 2} went or is going and how recovery might be improved. New data was also generated in this process. Production logs were run to understand where the CO{sub 2} was entering the reservoir related to core and log information and also to corroborate the simulation model. A methodology was developed and successfully tested for evaluating saturations in a cased-hole environment. Finally an experimental and theoretical program was initiated to relate laboratory work to field scale design and analysis of operations. This work found that an understanding of vertical and areal heterogeneity is crucial for understanding sweep processes as well as understanding appropriate mitigation techniques to improve the sweep. Production and injection logs can provide some understanding of that heterogeneity when core data is not available. The cased-hole saturation logs developed in the project will also be an important part of the evaluation of vertical heterogeneity. Evaluation of injection well/production well connectivities through statistical or numerical techniques were found to be as successful in evaluating CO{sub 2} floods as they are for waterfloods. These are likely to be the lowest cost techniques to evaluate areal sweep. Full field simulation and 4D seismic techniques are other possibilities but were beyond the scope of the project. Detailed simulation studies of pattern areas proved insightful both for doing a “post-mortem” analysis of the pilot area as well as a late-term, active portion of the Little Creek Field. This work also evaluated options for improving sweep in the current flood as well as evaluating options that could have been successful at recovering more oil. That simulation study was successful due to the integration of a large amount of data supplied by the operator as well as collected through the course of the project. While most projects would not have the abundance of data that Little Creek had, integration of the available data continues to be critical for both the design and evaluation stages of CO{sub 2} floods. For cases where data availability is limited, running injection/production logs and/or running cased-hole saturation tools to provide an indication of vertical heterogeneity will be important.« less
Laboratory grown subaerial biofilms on granite: application to the study of bioreceptivity.
Vázquez-Nion, Daniel; Silva, Benita; Troiano, Federica; Prieto, Beatriz
2017-01-01
Simulated environmental colonisation of granite was induced under laboratory conditions in order to develop an experimental protocol for studying bioreceptivity. The experimental set-up proved suitable for producing subaerial biofilms by inoculating granite blocks with planktonic multi-species phototrophic cultures derived from natural biofilms. The ability of four different cultures to form biofilms was monitored over a three-month growth period via colour measurements, quantification of photosynthetic pigments and EPS, and CLSM observations. One of the cultures under study, which comprised several taxa including Bryophyta, Charophyta, Chlorophyta and Cyanobacteria, was particularly suitable as an inoculum, mainly because of its microbial richness, its rapid adaptability to the substratum and its high colonisation capacity. The use of this culture as an inoculum in the proposed experimental set-up to produce subaerial biofilms under laboratory conditions will contribute to standardising the protocols involved, thus enabling more objective assessment of the bioreceptivity of granite in further experiments.
Workplace Exposure to Titanium Dioxide Nanopowder Released from a Bag Filter System
Ji, Jun Ho; Kim, Jong Bum; Lee, Gwangjae; Noh, Jung-Hun; Yook, Se-Jin; Cho, So-Hye; Bae, Gwi-Nam
2015-01-01
Many researchers who use laboratory-scale synthesis systems to manufacture nanomaterials could be easily exposed to airborne nanomaterials during the research and development stage. This study used various real-time aerosol detectors to investigate the presence of nanoaerosols in a laboratory used to manufacture titanium dioxide (TiO2). The TiO2 nanopowders were produced via flame synthesis and collected by a bag filter system for subsequent harvesting. Highly concentrated nanopowders were released from the outlet of the bag filter system into the laboratory. The fractional particle collection efficiency of the bag filter system was only 20% at particle diameter of 100 nm, which is much lower than the performance of a high-efficiency particulate air (HEPA) filter. Furthermore, the laboratory hood system was inadequate to fully exhaust the air discharged from the bag filter system. Unbalanced air flow rates between bag filter and laboratory hood systems could result in high exposure to nanopowder in laboratory settings. Finally, we simulated behavior of nanopowders released in the laboratory using computational fluid dynamics (CFD). PMID:26125024
NASA Astrophysics Data System (ADS)
Jagodziński, Piotr; Wolski, Robert
2015-02-01
Natural User Interfaces (NUI) are now widely used in electronic devices such as smartphones, tablets and gaming consoles. We have tried to apply this technology in the teaching of chemistry in middle school and high school. A virtual chemical laboratory was developed in which students can simulate the performance of laboratory activities similar to those that they perform in a real laboratory. Kinect sensor was used for the detection and analysis of the student's hand movements, which is an example of NUI. The studies conducted found the effectiveness of educational virtual laboratory. The extent to which the use of a teaching aid increased the students' progress in learning chemistry was examined. The results indicate that the use of NUI creates opportunities to both enhance and improve the quality of the chemistry education. Working in a virtual laboratory using the Kinect interface results in greater emotional involvement and an increased sense of self-efficacy in the laboratory work among students. As a consequence, students are getting higher marks and are more interested in the subject of chemistry.
NASA Technical Reports Server (NTRS)
Rochelle, W. C.; Liu, D. K.; Nunnery, W. J., Jr.; Brandli, A. E.
1975-01-01
This paper describes the application of the SINDA (systems improved numerical differencing analyzer) computer program to simulate the operation of the NASA/JSC MIUS integration and subsystems test (MIST) laboratory. The MIST laboratory is designed to test the integration capability of the following subsystems of a modular integrated utility system (MIUS): (1) electric power generation, (2) space heating and cooling, (3) solid waste disposal, (4) potable water supply, and (5) waste water treatment. The SINDA/MIST computer model is designed to simulate the response of these subsystems to externally impressed loads. The computer model determines the amount of recovered waste heat from the prime mover exhaust, water jacket and oil/aftercooler and from the incinerator. This recovered waste heat is used in the model to heat potable water, for space heating, absorption air conditioning, waste water sterilization, and to provide for thermal storage. The details of the thermal and fluid simulation of MIST including the system configuration, modes of operation modeled, SINDA model characteristics and the results of several analyses are described.