Science.gov

Sample records for offices simulations measurements

  1. Office ergonomics. Measurements for success.

    PubMed

    Martin, C; Andrew-Tuthill, D M

    1999-10-01

    The successful implementation of an ergonomics program requires collecting data on worksite history repetitive motion injuries and assessing the corporate ergonomic needs. It is important to solicit management, department, and employee support. Program success depends on creating process, training program, skilled assessors, and an accountability method. A thorough understanding and application of neutral posture and the three seated chair positions is essential. Evaluation of the entire individual work-space is essential. Precise measurements of the individual, the office chair, and the work surfaces should be completed, and heights adjusted to meet individual needs. Functional, totally adjustable office chairs are a necessity. Vendor selection criteria and vendor contracts for chairs and office equipment assure consistent specifications and cost control.

  2. Simulated Office Education Guidelines for Washington.

    ERIC Educational Resources Information Center

    Nelson, Frank; And Others

    The principles for use of the insurance, mercantile, and Lester-Hill simulation techniques in a program of office education are provided in this document. Guidelines for the development and use of such techniques in the classroom are suggested. The chapters outline the basic philosophy of student and business needs, curricular implications,…

  3. Survey of Characteristics of Measurement Services Offices.

    ERIC Educational Resources Information Center

    Erwin, T. Dary; And Others

    This paper briefly summarizes the findings from a national survey for the Measurement Services Association (MSA) of testing and measurement offices regarding their organizational characteristics and their activities and services. Questionnaires were mailed to all testing offices (n=146) at colleges and universities on the MSA Newsletter mailing…

  4. Job Simulation--The Future in Business and Office Education.

    ERIC Educational Resources Information Center

    Wells, Quentin T.

    Unlike ordinary computer simulations that imitate the conditions of a real-life situation and allow several variables to be input, job simulations program a microcomputer to simulate the functions of one or more pieces of business or office equipment and to provide hands-on, interactive instruction to students on how to use that equipment. Good…

  5. FLAIR: A Simulation Based on a Real Buying Office

    ERIC Educational Resources Information Center

    Mosich, Doris

    1974-01-01

    A simulation of a buying service for a number of retail stores, termed FLAIR, is described as a flexible instructional vehicle meeting the needs of business procedures trainees attending the Southern California Regional Occupational Center. Training objectives, office organization, and the importance of real-world simulation in developing…

  6. Practicum for Simulated Methods in Office Occupation Education. Final Report.

    ERIC Educational Resources Information Center

    Hanson, Garth A.

    Thirty-six participants and four observers representing 34 states attended the practicum at the Utah State University campus in Logan, July 8-19, 1968. The purpose was to provide high school business teachers with practical knowledge, experience, and materials for designing and operating simulated business offices in their classrooms. The…

  7. Automated office blood pressure measurement in primary care

    PubMed Central

    Myers, Martin G.; Kaczorowski, Janusz; Dawes, Martin; Godwin, Marshall

    2014-01-01

    Abstract Objective To provide FPs with detailed knowledge of automated office blood pressure (AOBP) measurement, its potential role in primary care, and its proper use in the diagnosis and management of hypertension. Sources of information Comprehensive monitoring and collection of scientific articles on AOBP by the authors since its introduction. Main message Automated office blood pressure measurement maintains a role for blood pressure (BP) readings taken in the office setting. Clinical research studies have reported a substantially stronger relationship between awake ambulatory BP measurement and AOBP measurement compared with manual BP recorded during routine visits to the patient’s physician. Automated office blood pressure measurement produces mean BP values comparable to awake ambulatory BP and home BP values. Compared with routine manual office BP measurement, AOBP correlates more strongly with awake ambulatory BP measurement, shows less digit preference, is more consistent from visit to visit, is similar both within and outside of the physician’s office, virtually eliminates office-induced hypertension, and is associated with less masked hypertension. It is estimated that more than 25% of Canadian primary care physicians are now using AOBP measurement in their office practices. The use of AOBP to diagnose hypertension has been recommended by the Canadian Hypertension Education Program since 2010. Conclusion There is now sufficient evidence to incorporate AOBP measurement into primary care as an alternative to manual BP measurement. PMID:24522674

  8. Measuring Officer Potential Using the OER

    DTIC Science & Technology

    2015-06-12

    opportunity. Most note that the lack of feedback during the rating period creates environments in which officers are not sure where they stand when it comes...counseling from an immediate supervisor, and more often than not, senior raters either do not counsel or provide meaningful feedback to subordinates on...transparent Leader Development and talent management tool. Now the Army must ensure that the words spoken by the Chief of Staff actually come to

  9. Simulated Office Education: Course of Study: Teacher's Manual and Student's Manual.

    ERIC Educational Resources Information Center

    Utah State Board for Vocational Education, Salt Lake City.

    Two separate manuals give detailed instructions for setting up and carrying out simulated office practice. The simulation design covers all office skills and all kinds of office situations, from management decisions to ground rules for coffee breaks and includes handling rush jobs. Procedures and roles for seven office positions, from vice…

  10. Adaptive thinking & leadership simulation game training for special forces officers.

    SciTech Connect

    Raybourn, Elaine Marie; Mendini, Kip; Heneghan, Jerry; Deagle, Edwin

    2005-07-01

    multiplayer simulation game is successfully used in the Special Forces Officer training program.

  11. The Patriot Company: A Simulated Office. Parkview High School, Little Rock, Arkansas.

    ERIC Educational Resources Information Center

    Smith, Phyllis W.

    The document is a student manual and teacher's manual for a simulated office practice class designed to give students training in a business office on school premises. In the simulation, students perform as office personnel and as customers and creditors. The first part of the guide, directed to students, contains: general information on the…

  12. Psychobiological stress response to a simulated school shooting in police officers.

    PubMed

    Strahler, Jana; Ziegert, Thomas

    2015-01-01

    Police work is one of the most demanding professions with various sources of high occupational stress. Among the most demanding tasks are amok situations, such as school shootings. Hardly anything is known about endocrine and cardiovascular markers in safety professionals during emergency situations in real life and how this relates to stress perception and management. This study will therefore explore police officers' stress responses to a reality-based school shooting simulation assessing neuroendocrine, cardiovascular, and psychological stress markers. A convenience sample of 50 police officers (39.5 ± 8.7 yrs, 9 women) participating in a basic or refresher amok training session for the German uniformed and criminal police were recruited. Saliva samples were collected shortly before the simulation task (school shooting), immediately after, 20 and 45 min after finishing the task for the assessment of cortisol and alpha-amylase (sAA), as markers of the hypothalamic-pituitary-adrenal axis and the autonomic nervous system, respectively. Heart rate (variability) was assessed continuously. Officers rated their actual mood right before and 10 min after the simulation. Subjective experience of task stressfulness was assessed minutes after finishing the simulation. Overall, the simulated school shooting did not result in changes of mood, tiredness, or calmness but higher restlessness was experienced during the basic training, which was also experienced as more controllable. Female officers reported to experience more strain and anxiety. Cortisol showed highest levels at the beginning of the training and steadily decreasing values thereafter. In contrast, sAA increased substantially right after the simulation with officers on the front position showing most pronounced changes. Cardiovascular reactivity was highest in officers acting on the side positions while advancing to find the suspect. Furthermore higher self-efficacy as well as, by trend, controllability and

  13. Photocopy of measured drawing (from First Coast Guard District Office, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Photocopy of measured drawing (from First Coast Guard District Office, John F. Kennedy Federal Building, Government Center, Boston, Massachusetts) designed by Edward P. Adams and Royal Luther, 1890 "PLAN FOR FRAMED DOUBLE DWELLING AT PORTLAND HEAD, ME., LIGHT STATION" - Portland Head Light, Portland Head, approximately 1/2 mile East of Shore Road, Cape Elizabeth, Cumberland County, ME

  14. Measuring Noncommissioned Officer Knowledge and Experience to Enable Tailored Training

    DTIC Science & Technology

    2011-11-01

    U.S. Army Research Institute for the Behavioral and Social Sciences Research Report 1952 Measuring Noncommissioned Officer...Knowledge and Experience to Enable Tailored Training Peter S. Schaefer U.S. Army Research Institute Paul N. Blankenbeckler Northrop...Grumman Corporation Christopher J. Brogdon Mercer University Consortium Research Fellows Program November 2011 Approved for

  15. Why use automated office blood pressure measurements in clinical practice?

    PubMed

    Andreadis, Emmanuel A; Angelopoulos, Epameinondas T; Agaliotis, Gerasimos D; Tsakanikas, Athanasios P; Mousoulis, George P

    2011-09-01

    Automated office blood pressure (AOBP) measurement with the patient resting alone in a quiet examining room can eliminate the white-coat effect associated with conventional readings taken by manual sphygmomanometer. The key to reducing the white-coat response appears to be multiple blood pressure (BP) readings taken in a non-observer office setting, thus eliminating any interaction that could provoke an office-induced increase in BP. Furthermore, AOBP readings have shown a higher correlation with the mean awake ambulatory BP compared with BP readings recorded in routine clinical practice. Although there is a paucity of studies connecting AOBP with organ damage, AOBP values were recently found to be equally associated with left ventricular mass index as those of ambulatory BP. This concludes that in contrast to routine manual office BP, AOBP readings compare favourably with 24-hour ambulatory BP measurements in the appraisal of cardiac remodelling and, as such, could be complementary to ambulatory readings in a way similar to home BP measurements.

  16. Novel Uses of Office-Based Measures of Arterial Compliance

    PubMed Central

    Townsend, Raymond R.

    2015-01-01

    Office-based blood pressure monitoring has been the primary way of managing the cardiovascular risk associated with a diagnosis of hypertension. As research unfolds the nature in which the pulse waveform is generated, additional insights beyond standard measures of systolic and diastolic blood pressure have emerged to help reclassify the cardiovascular risk of patients or point out patterns that have, in longitudinal cohort studies, shown promise as predictors of outcomes such as heart failure. In this review, we focus on the pressure profile in the proximal aorta that can be obtained easily and noninvasively from the radial or brachial artery during a clinical office encounter and the potential value of these measures in outcomes such as left ventricular hypertrophy and heart failure. PMID:27057290

  17. Laser Doppler pulp vitality measurements: simulation and measurement

    NASA Astrophysics Data System (ADS)

    Ertl, T.

    2017-02-01

    Frequently pulp vitality measurement is done in a dental practice by pressing a frozen cotton pellet on the tooth. This method is subjective, as the patient's response is required, sometimes painful and has moderate sensitivity and specificity. Other methods, based on optical or electrical measurement have been published, but didńt find wide spread application in the dental offices. Laser Doppler measurement of the blood flow in the pulp could be an objective method to measure pulp vitality, but the influence of the gingival blood flow on the measurements is a concern. Therefore experiments and simulations were done to learn more about the gingival blood flow in relation to the pulpal blood flow and how to minimize the influence. First patient measurements were done to show the feasibility clinically. Results: Monte Carlo simulations and bench experiments simulating the blood flow in and around a tooth show that both basic configurations, transmission and reflection measurements are possible. Most favorable is a multi-point measurement with different distances from the gingiva. Preliminary sensitivity / specificity are promising and might allow an objective and painless measurement of tooth vitality.

  18. Simulation Based Acquisition for NASA's Office of Exploration Systems

    NASA Technical Reports Server (NTRS)

    Hale, Joe

    2004-01-01

    In January 2004, President George W. Bush unveiled his vision for NASA to advance U.S. scientific, security, and economic interests through a robust space exploration program. This vision includes the goal to extend human presence across the solar system, starting with a human return to the Moon no later than 2020, in preparation for human exploration of Mars and other destinations. In response to this vision, NASA has created the Office of Exploration Systems (OExS) to develop the innovative technologies, knowledge, and infrastructures to explore and support decisions about human exploration destinations, including the development of a new Crew Exploration Vehicle (CEV). Within the OExS organization, NASA is implementing Simulation Based Acquisition (SBA), a robust Modeling & Simulation (M&S) environment integrated across all acquisition phases and programs/teams, to make the realization of the President s vision more certain. Executed properly, SBA will foster better informed, timelier, and more defensible decisions throughout the acquisition life cycle. By doing so, SBA will improve the quality of NASA systems and speed their development, at less cost and risk than would otherwise be the case. SBA is a comprehensive, Enterprise-wide endeavor that necessitates an evolved culture, a revised spiral acquisition process, and an infrastructure of advanced Information Technology (IT) capabilities. SBA encompasses all project phases (from requirements analysis and concept formulation through design, manufacture, training, and operations), professional disciplines, and activities that can benefit from employing SBA capabilities. SBA capabilities include: developing and assessing system concepts and designs; planning manufacturing, assembly, transport, and launch; training crews, maintainers, launch personnel, and controllers; planning and monitoring missions; responding to emergencies by evaluating effects and exploring solutions; and communicating across the OEx

  19. Simulation Based Acquisition for NASA's Office of Exploration Systems

    NASA Technical Reports Server (NTRS)

    Hale, Joe

    2004-01-01

    In January 2004, President George W. Bush unveiled his vision for NASA to advance U.S. scientific, security, and economic interests through a robust space exploration program. This vision includes the goal to extend human presence across the solar system, starting with a human return to the Moon no later than 2020, in preparation for human exploration of Mars and other destinations. In response to this vision, NASA has created the Office of Exploration Systems (OExS) to develop the innovative technologies, knowledge, and infrastructures to explore and support decisions about human exploration destinations, including the development of a new Crew Exploration Vehicle (CEV). Within the OExS organization, NASA is implementing Simulation Based Acquisition (SBA), a robust Modeling & Simulation (M&S) environment integrated across all acquisition phases and programs/teams, to make the realization of the President s vision more certain. Executed properly, SBA will foster better informed, timelier, and more defensible decisions throughout the acquisition life cycle. By doing so, SBA will improve the quality of NASA systems and speed their development, at less cost and risk than would otherwise be the case. SBA is a comprehensive, Enterprise-wide endeavor that necessitates an evolved culture, a revised spiral acquisition process, and an infrastructure of advanced Information Technology (IT) capabilities. SBA encompasses all project phases (from requirements analysis and concept formulation through design, manufacture, training, and operations), professional disciplines, and activities that can benefit from employing SBA capabilities. SBA capabilities include: developing and assessing system concepts and designs; planning manufacturing, assembly, transport, and launch; training crews, maintainers, launch personnel, and controllers; planning and monitoring missions; responding to emergencies by evaluating effects and exploring solutions; and communicating across the OEx

  20. Automatic Office Blood Pressure Measured without Doctors or Nurses Present

    PubMed Central

    Ishikawa, Joji; Nasothimiou, Efthimia G; Karpettas, Nikos; McDoniel, Scott; Feltheimer, Seth D; Stergiou, George S; Pickering, Thomas G; Schwartz, Joseph E

    2012-01-01

    Backgrounds We evaluated the agreement between office blood pressure (OBP) measured by mercury sphygmomanometer (Sphyg) and automatic (Auto) device without any observers, and compared Auto and Sphyg OBP to ambulatory (ABP) and home blood pressure (HBP). Methods OBP was measured in 75 hypertensive patients at 2 sites using an automatic monitor without a doctor or nurse present and by Sphyg during 3 clinic visits. Between visits, ABP and HBP monitoring were also performed. Results Mean Auto OBP was similar to Sphyg OBP and they were closely correlated (ICC=0.84 for systolic and 0.91 for diastolic OBPs); however, the difference between Auto and Sphyg systolic OBP (1.6±8.2 mmHg) varied by the first office visit, gender, and the site. Auto systolic OBP was lower than both systolic awake ABP (137.1±14.7 mmHg) and HBP (139.2±15.6 mmHg). Auto systolic OBP and Sphyg OBP were similarly correlated with systolic awake ABP (both r=0.59, P<0.001). Mean Auto diastolic OBP was similar to Sphyg OBP (81.1±11.3 vs. 80.3±13.3 mmHg, P=0.20, ICC=0.91), diastolic awake ABP and HBP. Auto diastolic OBP and Sphyg OBP were related to diastolic awake ABP (both r>0.68, P<0.001). In multivariable analyses, neither OBP measure was a significantly stronger predictor of out-of-office BP than the other. Conclusion Auto systolic OBP measured without a doctor or nurse present was lower than systolic awake ABP and HBP. Auto and rigorously assessed Sphyg OBP had similar means and were similarly related to awake ABP. Auto OBP might be an advantageous alternative to Sphyg measurements in the usual clinic setting. PMID:22425703

  1. B.O.P., Inc.: A Simulated Mortgage and Loan Office: Exemplary Project in Vocational Education: Student's Manual.

    ERIC Educational Resources Information Center

    Bingham County Career Education, Blackfoot, ID.

    BOP, Inc. is a mobile educational service that places the student in a simulated mortgage and loan office to provide a realistic office learning environment. The student manual opens with a brief reference information section on: the purposes of an office simulation, an explanation of a mortgage loan office, an outline of normal business…

  2. Simulation of realistic retinoscopic measurement

    NASA Astrophysics Data System (ADS)

    Tan, Bo; Chen, Ying-Ling; Baker, K.; Lewis, J. W.; Swartz, T.; Jiang, Y.; Wang, M.

    2007-03-01

    Realistic simulation of ophthalmic measurements on normal and diseased eyes is presented. We use clinical data of ametropic and keratoconus patients to construct anatomically accurate three-dimensional eye models and simulate the measurement of a streak retinoscope with all the optical elements. The results show the clinical observations including the anomalous motion in high myopia and the scissors reflex in keratoconus. The demonstrated technique can be applied to other ophthalmic instruments and to other and more extensively abnormal eye conditions. It provides promising features for medical training and for evaluating and developing ocular instruments.

  3. Computational Seebeck Coefficient Measurement Simulations

    PubMed Central

    Martin, Joshua

    2012-01-01

    We have employed finite element analysis to develop computational Seebeck coefficient metrology simulations. This approach enables a unique exploration of multiple probe arrangements and measurement techniques within the same temporal domain. To demonstrate the usefulness of this approach, we have performed these Seebeck coefficient measurement simulations to quantitatively explore perturbations to voltage and temperature correspondence, by comparing simultaneous and staggered data acquisition techniques under the quasi-steady-state condition. The results indicate significant distortions to the Seebeck coefficient and a strong dependence on the time delay, the acquisition sequence, and the probe arrangement. PMID:26900521

  4. Measurements of chlorinated volatile organic compounds emitted from office printers and photocopiers.

    PubMed

    Kowalska, Joanna; Szewczyńska, Małgorzata; Pośniak, Małgorzata

    2015-04-01

    Office devices can release volatile organic compounds (VOCs) partly generated by toners and inks, as well as particles of paper. The aim of the presented study is to identify indoor emissions of volatile halogenated organic compounds into the office workspace environment. Mixtures of organic pollutants emitted by seven office devices, i.e. printers and copiers, were analyzed by taking samples in laboratory conditions during the operation of these appliances. Tests of volatile organic compound emissions from selected office devices were conducted in a simulated environment (test chamber). Samples of VOCs were collected using three-layered thermal desorption tubes. Separation and identification of organic pollutant emissions were made using thermal desorption combined with gas chromatography coupled to mass spectrometry. Test chamber studies indicated that operation of the office printer and copier would contribute to the significant concentration level of VOCs in typical office indoor air. Among the determined volatile halogenated compounds, only chlorinated organic compounds were identified, inter alia: trichloroethylene - carcinogenic - and tetrachloroethylene - possibly carcinogenic to human. The results show that daily exposure of an office worker to chemical factors released by the tested printing and copying units can be variable in terms of concentrations of VOCs. The highest emissions in the test chamber during printing were measured for ethylbenzene up to 41.3 μg m(-3), xylenes up to 40.5 μg m(-3) and in case of halogenated compounds the highest concentration for chlorobenzene was 6.48 μg m(-3). The study included the comparison of chamber concentrations and unit-specific emission rates of selected VOCs and the identified halogenated compounds. The highest amount of total VOCs was emitted while copying with device D and was rated above 1235 μg m(-3) and 8400 μg unit(-1) h(-1) on average.

  5. Expanding the Lester Hill Experience: A Report on Two 'Branch Office' Simulations

    ERIC Educational Resources Information Center

    Melvin, Opal B.

    1976-01-01

    Describes use of the Lester Hill Office Simulation, a program taught at the Tishomingo County Area Vocational-Technical Center in Mississippi. A fictitious company which provides students with the opportunity to gain realistic office experience in a classroom setting. Suggested ideas and optional activities can be used by teachers as a starting…

  6. Longitudinal Validation of Non-Cognitive Officer Selection Measures for the U.S. Army Officer Candidate School (OCS)

    DTIC Science & Technology

    2012-09-01

    predictors ) collected at the beginning of OCS in 2008, (b) attitudinal and performance measures collected at the completion of OCS, (c) attitudinal and...conducted to validate the Officer Background and Experiences Form (OBEF) as a predictor of OCS-commissioned officer performance , continuance, and... performance criteria at the End of OCS. However, the Core Work Values were strong predictors of In-Unit technical knowledge and physical fitness

  7. Measurement of particle concentrations in a dental office.

    PubMed

    Sotiriou, Maria; Ferguson, Stephen F; Davey, Mark; Wolfson, Jack M; Demokritou, Philip; Lawrence, Joy; Sax, Sonja N; Koutrakis, Petros

    2008-02-01

    Particles in a dental office can be generated by a number of instruments, such as air-turbine handpieces, low-speed handpieces, ultrasonic scalers, bicarbonate polishers, polishing cups, as well as drilling and air sprays inside the oral cavity. This study examined the generation of particles during dental drilling and measured particle size, mass, and trace elements. The air sampling techniques included both continuous and integrated methods. The following particle continuous measurements were taken every minute: (1) size-selective particle number concentration (Climet); (2) total particle number concentration (PTRAK), and; (3) particle mass concentration (DustTrak). Integrated particle samples were collected for about 5 h on each of five sampling days, using a PM(2.5) sampler (ChemComb) for elemental/organic carbon analysis, and a PM(10) sampler (Harvard Impactor) for mass and elemental analyses. There was strong evidence that these procedures result in particle concentrations above background. The dental procedures produced number concentrations of relatively small particles (<0.5 microm) that were much higher than concentrations produced for the relatively larger particles (>0.5 microm). Also, these dental procedures caused significant elevation above background of certain trace elements (measured by X-ray fluorescence) but did not cause any elevation of elemental carbon (measured by thermal optical reflectance). Dental drilling procedures aerosolize saliva and products of drilling, producing particles small enough to penetrate deep into the lungs. The potential health impacts of the exposure of dental personnel to such particles need to be evaluated. Increased ventilation and personal breathing protection could be used to minimize harmful effects.

  8. Simmons Insurance Agency. A Clerk-Typist Position Simulation. Student Packet III. Office Occupations.

    ERIC Educational Resources Information Center

    Georgia State Univ., Atlanta.

    This is the third of five student packets forming part of a position simulation developed for use in an office applications laboratory at the postsecondary level. The purpose of the simulation is to give the student an opportunity to become familiar with the tasks and duties performed by a clerk-typist working for an independent insurance agency.…

  9. Simmons Insurance Agency. A Clerk-Typist Position Simulation. Student Packet II. Office Occupations.

    ERIC Educational Resources Information Center

    Georgia State Univ., Atlanta.

    This is the second of five student packets forming part of a position simulation developed for use in an office applications laboratory at the postsecondary level. The purpose of the simulation is to give the student an opportunity to become familiar with the tasks and duties performed by a clerk-typist working for an independent insurance agency.…

  10. Simmons Insurance Agency. A Clerk-Typist Position Simulation. Student Packet IV. Office Occupations.

    ERIC Educational Resources Information Center

    Georgia State Univ., Atlanta.

    This is the fourth of five student packets forming part of a position simulation developed for use in an office applications laboratory at the postsecondary level. The purpose of the simulation is to give the student an opportunity to become familiar with the tasks and duties performed by a clerk-typist working for an independent insurance agency.…

  11. Measurement outcomes from hip simulators.

    PubMed

    de Villiers, Danielle; Shelton, Julia C

    2016-05-01

    Simulation of wear in total hip replacements has been recognised as an important factor in determining the likelihood of clinical success. However, accurate measurement of wear can be problematic with factors such as number and morphology of wear particles produced as well as ion release proving more important in the biological response to hip replacements than wear volume or wear rate alone. In this study, hard-on-hard (CoCr alloy, AgCrN coating) and hard-on-soft (CoCr alloy and CrN coating on vitamin E blended highly cross-linked polyethylene) bearing combinations were tested in an orbital hip simulator under standard and some adverse conditions. Gravimetric wear rates were determined for all bearings, with cobalt and where applicable, silver release determined throughout testing. Isolation of wear particles from the lubricating fluid was used to determine the influence of different bearing combinations and wear conditions on particle morphology. It was found that cobalt and silver could be measured in the lubricating fluid even when volumetric wear was not detectable. In hard-on-hard bearings, Pearson's correlation of 0.98 was established between metal release into the lubricating fluid and wear volume. In hard-on-soft bearings, coating the head did not influence the polyethylene wear rates measured under standard conditions but did influence the cobalt release; the diameter influenced both polyethylene wear and cobalt release, and the introduction of adverse testing generated smaller polyethylene particles. While hip simulators can be useful to assess the wear performance of a new material or design, measurement of other outcomes may yield greater insight into the clinical behaviour of the bearings in vivo.

  12. A comparison of trunk biomechanics, musculoskeletal discomfort and productivity during simulated sit-stand office work.

    PubMed

    Karakolis, Thomas; Barrett, Jeff; Callaghan, Jack P

    2016-10-01

    Sedentary office work has been shown to cause low back discomfort and potentially cause injury. Prolonged standing work has been shown to cause discomfort. The implementation of a sit-stand paradigm is hypothesised to mitigate discomfort and prevent injury induced by prolonged exposure to each posture in isolation. This study explored the potential of sit-stand to reduce discomfort and prevent injury, without adversely affecting productivity. Twenty-four participants performed simulated office work in three different conditions: sitting, standing and sit-stand. Variables measured included: perceived discomfort, L4-L5 joint loading and typing/mousing productivity. Working in a sit-stand paradigm was found to have the potential to reduce discomfort when compared to working in a sitting or standing only configuration. Sit-stand was found to be associated with reduced lumbar flexion during sitting compared to sitting only. Increasing lumbar flexion during prolonged sitting is a known injury mechanism. Therefore, sit-stand exhibited a potentially beneficial response of reduced lumbar flexion that could have the potential to prevent injury. Sit-stand had no significant effect on productivity. Practitioner Summary: This study has contributed foundational elements to guide usage recommendations for sit-stand workstations. The sit-stand paradigm can reduce discomfort; however, working in a sit-stand ratio of 15:5 min may not be the most effective ratio. More frequent posture switches may be necessary to realise the full benefit of sit-stand.

  13. Numerical Simulations of Instabilities in Single-Hole Office Elements

    NASA Technical Reports Server (NTRS)

    Ahuja, Vineet; Hosangadi, Ashvin; Hitt, Matthew A.; Lineberry, David M.

    2013-01-01

    An orifice element is commonly used in liquid rocket engine test facilities either as a flow metering device, a damper for acoustic resonance or to provide a large reduction in pressure over a very small distance in the piping system. While the orifice as a device is largely effective in stepping down pressure, it is also susceptible to a wake-vortex type instability that generates pressure fluctuations that propagate downstream and interact with other elements of the test facility resulting in structural vibrations. Furthermore in piping systems an unstable feedback loop can exist between the vortex shedding and acoustic perturbations from upstream components resulting in an amplification of the modes convecting downstream. Such was the case in several tests conducted at NASA as well as in the Ariane 5 strap-on P230 engine in a static firing test where pressure oscillations of 0.5% resulted in 5% thrust oscillations. Exacerbating the situation in cryogenic test facilities, is the possibility of the formation of vapor clouds when the pressure in the wake falls below the vapor pressure leading to a cavitation instability that has a lower frequency than the primary wake-vortex instability. The cavitation instability has the potential for high amplitude fluctuations that can cause catastrophic damage in the facility. In this paper high-fidelity multi-phase numerical simulations of an orifice element are used to characterize the different instabilities, understand the dominant instability mechanisms and identify the tonal content of the instabilities.

  14. Principles of Blood Pressure Measurement - Current Techniques, Office vs Ambulatory Blood Pressure Measurement.

    PubMed

    Vischer, Annina S; Burkard, Thilo

    2016-07-15

    Blood pressure measurement has a long history and a crucial role in clinical medicine. Manual measurement using a mercury sphygmomanometer and a stethoscope remains the Gold Standard. However, this technique is technically demanding and commonly leads to faulty values. Automatic devices have helped to improve and simplify the technical aspects, but a standardised procedure of obtaining comparable measurements remains problematic and may therefore limit their validity in clinical practice. This underlines the importance of less error-prone measurement methods such as ambulatory or home blood pressure measurements and automated office blood pressure measurements. These techniques may help to uncover patients with otherwise unrecognised or overestimated arterial hypertension. Additionally these techniques may yield a better prognostic value.

  15. Word Processing Services, Inc. A Task Simulation for Office Occupations. Employer Manual.

    ERIC Educational Resources Information Center

    Georgia State Univ., Atlanta.

    This word processing task simulation was developed for use in an office occupations laboratory at the postsecondary level. Its purpose is to give the student an opportunity to become familiar with the tasks and duties that may be performed by word processing personnel. This "employer" manual is designed to aid teachers in implementing the word…

  16. Constraints Influencing Measurement of the Utilization of Unrestricted Line Officer Financial Management Subspecialists

    DTIC Science & Technology

    1978-03-01

    generated for personnel who were trained and educated in the skills needed for financial management as encompassed by the controllership function. In 1951...measurement of the utilization of unrestricted line officer financial management subspecialists. Tirrell, William Barclay http://hdl.handle.net/10945...18385 Downloaded from NPS Archive: Calhoun CONSTRAINTS INFLUENCING MEASUREMENT OF THE UTILIZATION OF UNRESTRICTED LINE OFFICER FINANCIAL MANAGEMENT

  17. B.O.P., Inc.: A Simulated Mortgage and Loan Office. Exemplary Project in Vocational Education: Teacher's Manual.

    ERIC Educational Resources Information Center

    Bingham County Career Education, Blackfoot, ID.

    BOP, Inc., is a simulated mortgage and loan office serving students in the high schools of Bingham County, Idaho, through a mobile educational service program. The program's primary purpose is to provide work experiences for high school students who have office skills so that they can make decisions about working in an office. The teacher's manual…

  18. Energy Savings Modeling of Standard Commercial Building Re-tuning Measures: Large Office Buildings

    SciTech Connect

    Fernandez, Nicholas; Katipamula, Srinivas; Wang, Weimin; Huang, Yunzhi; Liu, Guopeng

    2012-06-01

    Today, many large commercial buildings use sophisticated building automation systems (BASs) to manage a wide range of building equipment. While the capabilities of BASs have increased over time, many buildings still do not fully use the BAS's capabilities and are not properly commissioned, operated or maintained, which leads to inefficient operation, increased energy use, and reduced lifetimes of the equipment. This report investigates the energy savings potential of several common HVAC system retuning measures on a typical large office building prototype model, using the Department of Energy's building energy modeling software, EnergyPlus. The baseline prototype model uses roughly as much energy as an average large office building in existing building stock, but does not utilize any re-tuning measures. Individual re-tuning measures simulated against this baseline include automatic schedule adjustments, damper minimum flow adjustments, thermostat adjustments, as well as dynamic resets (set points that change continuously with building and/or outdoor conditions) to static pressure, supply air temperature, condenser water temperature, chilled and hot water temperature, and chilled and hot water differential pressure set points. Six combinations of these individual measures have been formulated - each designed to conform to limitations to implementation of certain individual measures that might exist in typical buildings. All of these measures and combinations were simulated in 16 cities representative of specific U.S. climate zones. The modeling results suggest that the most effective energy savings measures are those that affect the demand-side of the building (air-systems and schedules). Many of the demand-side individual measures were capable of reducing annual HVAC system energy consumption by over 20% in most cities that were modeled. Supply side measures affecting HVAC plant conditions were only modestly successful (less than 5% annual HVAC energy savings for

  19. Energy savings modelling of re-tuning energy conservation measures in large office buildings

    SciTech Connect

    Fernandez, Nick; Katipamula, Srinivas; Wang, Weimin; Huang, Yunzhi; Liu, Guopeng

    2014-10-20

    Today, many large commercial buildings use sophisticated building automation systems (BASs) to manage a wide range of building equipment. While the capabilities of BASs have increased over time, many buildings still do not fully use the BAS’s capabilities and are not properly commissioned, operated or maintained, which leads to inefficient operation, increased energy use, and reduced lifetimes of the equipment. This paper investigates the energy savings potential of several common HVAC system re-tuning measures on a typical large office building, using the Department of Energy’s building energy modeling software, EnergyPlus. The baseline prototype model uses roughly as much energy as an average large office building in existing building stock, but does not utilize any re-tuning measures. Individual re-tuning measures simulated against this baseline include automatic schedule adjustments, damper minimum flow adjustments, thermostat adjustments, as well as dynamic resets (set points that change continuously with building and/or outdoor conditions) to static pressure, supply-air temperature, condenser water temperature, chilled and hot water temperature, and chilled and hot water differential pressure set points. Six combinations of these individual measures have been formulated – each designed to conform to limitations to implementation of certain individual measures that might exist in typical buildings. All the individual measures and combinations were simulated in 16 climate locations representative of specific U.S. climate zones. The modeling results suggest that the most effective energy savings measures are those that affect the demand-side of the building (air-systems and schedules). Many of the demand-side individual measures were capable of reducing annual total HVAC system energy consumption by over 20% in most cities that were modeled. Supply side measures affecting HVAC plant conditions were only modestly successful (less than 5% annual HVAC energy

  20. Measures for assessing architectural speech security (privacy) of closed offices and meeting rooms

    NASA Astrophysics Data System (ADS)

    Gover, Bradford N.; Bradley, John S.

    2004-12-01

    Objective measures were investigated as predictors of the speech security of closed offices and rooms. A new signal-to-noise type measure is shown to be a superior indicator for security than existing measures such as the Articulation Index, the Speech Intelligibility Index, the ratio of the loudness of speech to that of noise, and the A-weighted level difference of speech and noise. This new measure is a weighted sum of clipped one-third-octave-band signal-to-noise ratios; various weightings and clipping levels are explored. Listening tests had 19 subjects rate the audibility and intelligibility of 500 English sentences, filtered to simulate transmission through various wall constructions, and presented along with background noise. The results of the tests indicate that the new measure is highly correlated with sentence intelligibility scores and also with three security thresholds: the threshold of intelligibility (below which speech is unintelligible), the threshold of cadence (below which the cadence of speech is inaudible), and the threshold of audibility (below which speech is inaudible). The ratio of the loudness of speech to that of noise, and simple A-weighted level differences are both shown to be well correlated with these latter two thresholds (cadence and audibility), but not well correlated with intelligibility. .

  1. Impact of human presence on secondary organic aerosols derived from ozone-initiated chemistry in a simulated office environment.

    PubMed

    Fadeyi, Moshood O; Weschler, Charles J; Tham, Kwok W; Wu, Wei Y; Sultan, Zuraimi M

    2013-04-16

    Several studies have documented reductions in indoor ozone levels that occur as a consequence of its reactions with the exposed skin, hair and clothing of human occupants. One would anticipate that consumption of ozone via such reactions would impact co-occurring products derived from ozone's reactions with various indoor pollutants. The present study examines this possibility for secondary organic aerosols (SOA) derived from ozone-initiated chemistry with limonene, a commonly occurring indoor terpene. The experiments were conducted at realistic ozone and limonene concentrations in a 240 m(3) chamber configured to simulate a typical open office environment. During an experiment the chamber was either unoccupied or occupied with 18-20 workers. Ozone and particle levels were continuously monitored using a UV photometric ozone analyzer and a fast mobility particle sizer (FMPS), respectively. Under otherwise identical conditions, when workers were present in the simulated office the ozone concentrations were approximately two-thirds and the SOA mass concentrations were approximately one-half of those measured when the office was unoccupied. This was observed whether new or used filters were present in the air handling system. These results illustrate the importance of accounting for occupancy when estimating human exposure to pollutants in various indoor settings.

  2. Measuring Satisfaction in the Program Manager, Procuring Contracting Officer Relationship

    DTIC Science & Technology

    1997-12-01

    44 5. Attaining Customer Satisfaction * 44 6. Inhibitors of Customer Satisfaction 45 Vlll 7. Measuring Customer Satisfaction 47 a. Preconditions...customer satisfaction issues, there has been little research to determine the optimal method for measuring customer satisfaction in the PM - PCO...business. As a result, for Executive departments of the Federal Government, measuring customer satisfaction is no longer the exception but the rule

  3. Genetic influence on blood pressure measured in the office, under laboratory stress and during real life

    PubMed Central

    Wang, Xiaoling; Ding, Xiuhua; Su, Shaoyong; Harshfield, Gregory; Treiber, Frank; Snieder, Harold

    2013-01-01

    To determine to what extent the genetic influences on blood pressure (BP) measured in the office, under psychologically stressful conditions in the laboratory and during real life are different from each other. Office BP, BP during a video game challenge and a social stressor interview, and 24-h ambulatory BP were measured in 238 European American and 186 African American twins. BP values across the two tasks were averaged to represent stress levels. Genetic model fitting showed no ethnic or gender differences for any of the measures. The model fitting resulted in heritability estimates of 63, 75 and 71% for office, stress and 24-h systolic BP (SBP) and 59, 67 and 69% for diastolic BP (DBP), respectively. Up to 81% of the heritability of office SBP and 71% of office DBP were attributed to genes that also influenced stress BP. However, only 45% of the heritability of 24-h SBP and 49% of 24-h DBP were attributed to genes that also influence office BP. Similarly, about 39% of the heritability of 24-h SBP and 42% of 24-h DBP were attributed to genes that also influence stress BP. Substantial overlap exists between genes that influence BP measured in the office, under laboratory stress and during real life. However, significant genetic components specific to each BP measurement also exist. These findings suggest that partly different genes or sets of genes contribute to BP regulation in different conditions. PMID:21068740

  4. A study of ventilation measurement in an office building

    SciTech Connect

    Dols, W.S.; Persily, A.K.

    1995-09-01

    The National Institute of Standards and Technology has conducted a study of ventilation and ventilation measurement techniques in the Bonneville Power Administration (BPA) Building in Portland, Oregon. The project involved the use of the following outdoor air ventilation measurement techniques: tracer gas decay measurements of whole-building air change rates, the determination of air change rates based on peak carbon dioxide (CO{sub 2}) concentrations, the determination of percent outdoor air intake using tracer gas (sulfur hexafluoride and occupant-generated CO{sub 2}), and direct airflow rate measurements within the air handling system. In addition, air change rate measurements made approximately three years apart with an automated tracer gas decay system were compared. Airflow rates were measured in the air handling system ductwork using pitot tube, hot-wire anemometer, and vane anemometer traverses, and good agreement was obtained between the different techniques. While accurate determinations of percent outdoor air intake were achieved using tracer gas techniques, the use of CO{sub 2} detector tubes yielded unreliable results. Reliable determinations of ventilation rates per person were made based on SF{sub 6} decay and direct airflow rate measurements, but the use of peak CO{sub 2} concentrations led to overestimations of building air change rates. The measured values of the whole-building air change rates, and their dependence on outdoor air temperature, did not change significantly over a three-year period. The whole-building air change rate under minimum outdoor air intake conditions was determined to be twice the outdoor air intake rate provided by the minimum outdoor air intake fans due to leakage through the main outdoor air intake dampers.

  5. A Web-Based Lean Simulation Game for Office Operations: Training the Other Side of a Lean Enterprise

    ERIC Educational Resources Information Center

    Kuriger, Glenn W.; Wan, Huang-da; Mirehei, S. Moussa; Tamma, Saumya; Chen, F. Frank

    2010-01-01

    This research proposes a Web-based version of a lean office simulation game (WeBLOG). The game is designed to be used to train lean concepts to office and administrative personnel. This group belongs to the frequently forgotten side of a lean enterprise. Over four phases, the game presents the following seven lean tools: one-piece flow,…

  6. A Web-Based Lean Simulation Game for Office Operations: Training the Other Side of a Lean Enterprise

    ERIC Educational Resources Information Center

    Kuriger, Glenn W.; Wan, Huang-da; Mirehei, S. Moussa; Tamma, Saumya; Chen, F. Frank

    2010-01-01

    This research proposes a Web-based version of a lean office simulation game (WeBLOG). The game is designed to be used to train lean concepts to office and administrative personnel. This group belongs to the frequently forgotten side of a lean enterprise. Over four phases, the game presents the following seven lean tools: one-piece flow,…

  7. Power levels in office equipment: Measurements of new monitors and personal computers

    SciTech Connect

    Roberson, Judy A.; Brown, Richard E.; Nordman, Bruce; Webber, Carrie A.; Homan, Gregory H.; Mahajan, Akshay; McWhinney, Marla; Koomey, Jonathan G.

    2002-05-14

    Electronic office equipment has proliferated rapidly over the last twenty years and is projected to continue growing in the future. Efforts to reduce the growth in office equipment energy use have focused on power management to reduce power consumption of electronic devices when not being used for their primary purpose. The EPA ENERGY STAR[registered trademark] program has been instrumental in gaining widespread support for power management in office equipment, and accurate information about the energy used by office equipment in all power levels is important to improving program design and evaluation. This paper presents the results of a field study conducted during 2001 to measure the power levels of new monitors and personal computers. We measured off, on, and low-power levels in about 60 units manufactured since July 2000. The paper summarizes power data collected, explores differences within the sample (e.g., between CRT and LCD monitors), and discusses some issues that arise in m etering office equipment. We also present conclusions to help improve the success of future power management programs.Our findings include a trend among monitor manufacturers to provide a single very low low-power level, and the need to standardize methods for measuring monitor on power, to more accurately estimate the annual energy consumption of office equipment, as well as actual and potential energy savings from power management.

  8. Short-Duration Simulations from Measurements.

    SciTech Connect

    Mitchell, Dean J.; Enghauser, Michael

    2014-08-01

    A method is presented that ascribes proper statistical variability to simulations that are derived from longer-duration measurements. This method is applicable to simulations of either real-value or integer-value data. An example is presented that demonstrates the applicability of this technique to the synthesis of gamma-ray spectra.

  9. Office, ambulatory and home blood pressure measurement in children and adolescents.

    PubMed

    Karpettas, Nikos; Kollias, Anastasios; Vazeou, Andriani; Stergiou, George S

    2010-11-01

    There is an increasing interest in pediatric hypertension, the prevalence of which is rising in parallel with the obesity epidemic. Traditionally the assessment of hypertension in children has relied on office blood pressure (BP) measurements by the physician. However, as in adults, office BP might be misleading in children mainly due to the white coat and masked hypertension phenomena. Thus, out-of-office BP assessment, using ambulatory or home monitoring, has gained ground for the accurate diagnosis of hypertension and decision-making. Ambulatory monitoring is regarded as indispensable for the evaluation of pediatric hypertension. Preliminary data support the usefulness of home monitoring, yet more evidence is needed. Office, ambulatory and home BP normalcy tables providing thresholds for diagnosis have been published and should be used for the assessment of elevated BP in children.

  10. Comparison of HEU Measurements Using Measured and Simulated Data

    SciTech Connect

    Hutchinson, Jesson D.; Sood, Avneet; Smith-Nelson, Mark A.; Dinwiddie, Derek R.; Myers, William L.

    2012-06-19

    Correlated neutron data analyzed using the Feynman Variance-to-Mean method are can be used to assess the multiplication and mass of special nuclear material (SNM) systems. After list-mode data are acquired, the multiplication and mass can be determined using detector parameters. This work compares data sets that were measured to simulated data using recent MCNP list-mode modifications. In addition, both sets of data are analyzed using both measured and simulated parameters to infer the system multiplication.

  11. Energy and Cost Savings of Retro-Commissioning and Retrofit Measures for Large Office Buildings

    SciTech Connect

    Wang, Weimin; Zhang, Jian; Moser, Dave; Liu, Guopeng; Athalye, Rahul A.; Liu, Bing

    2012-08-03

    This paper evaluates the energy and cost savings of seven retro-commissioning measures and 29 retrofit measures applicable to most large office buildings. The baseline model is for a hypothetical building with characteristics of large office buildings constructed before 1980. Each retro-commissioning measure is evaluated against the original baseline in terms of its potential of energy and cost savings while each retrofit measure is evaluated against the commissioned building. All measures are evaluated in five locations (Miami, Las Vegas, Seattle, Chicago and Duluth) to understand the impact of weather conditions on energy and cost savings. The results show that implementation of the seven operation and maintenance measures as part of a retro-commissioning process can yield an average of about 22% of energy use reduction and 14% of energy cost reduction. Widening zone temperature deadband, lowering VAV terminal minimum air flow set points and lighting upgrades are effective retrofit measures to be considered.

  12. Comparative reliability of different instruments used to measure the severity of musculoskeletal disorders in office workers.

    PubMed

    Shariat, Ardalan; Tamrin, Shamsul Bahri Mohd; Arumugam, Manohar; Danaee, Mahmoud; Ramasamy, Rajesh

    2016-06-08

    The accuracy of instruments such as questionnaires and the goniometer are critical for measuring the severity of musculoskeletal disorders among office workers. To determine the reliability of the Cornell questionnaire, goniometer and Borg questionnaire, which are commonly used instruments to assess the severity of musculoskeletal disorders in office workers. One hundred twenty healthy office workers, body mass: 87.1 ± 10.3 (kg), age: 27 ± 5.1 (years), height: 1.78 ± 0.16 (m), (mean ± SD), who had at least 1 year of experience in office working, were chosen randomly. A plastic goniometer (30" height) was used three times to measure the range of motion in the neck, hip, knee and shoulder area, with a period of one hour between measurements to evaluate the test-retest accuracy. The Cornell questionnaire was used to measure the severity of musculoskeletal disorders and the Borg scale was used to measure perceived exertion. The questionnaires were filled out twice with a gap of 2 weeks between measurements. The Inter-class Correlation Co-efficient (ICC) indicated that all instrument sub-scales showed high levels of repeatability. The ICC coefficient was (0.805-0.954, p <0.001) for the Borg scale, (0.785-0.978, p <0.001) for the goniometer and (0.883-0.975, p <0.001) for the Cornell questionnaire. The Cornell questionnaire, goniometer and Borg questionnaire all exhibit high reliability when used for the evaluation of the severity of musculoskeletal disorders in office workers.

  13. A Simulation Tool for the Duties of Computer Specialist Non-Commissioned Officers on a Turkish Air Force Base

    DTIC Science & Technology

    2009-09-01

    at the MOVES Institute A SIMULATION TOOL FOR THE DUTIES OF COMPUTER SPECIALIST NON-COMMISSIONED OFFICERS ON A TURKISH AIR FORCE BASE by...REPORT DATE September 2009 1. AGENCY USE ONLY (Leave blank) 4. TITLE AND SUBTITLE A Simulation Tool for the Duties of Computer Specialist...simulation tool by using a prototypical model of the computer system specialist non-commissioned officers’ jobs on a Turkish Air Force Base, and to

  14. Better medical office safety culture is not associated with better scores on quality measures.

    PubMed

    Hagopian, Benjamin; Singer, Mendel E; Curry-Smith, Anne C; Nottingham, Kelly; Hickner, John

    2012-03-01

    A strong safety culture is an essential element of safe medical practice. Few studies, however, have studied the link between safety culture and clinical quality outcomes. In this study, we examined the association between safety culture and quality measures in primary care offices. A total of 24 primary care offices in Cleveland, Ohio. The Medical Office Survey on Patient Safety was administered to clinicians and support staff to rate 12 dimensions of safety culture and a single overall patient safety rating. An average of the 12 safety culture dimension scores was calculated to produce an aggregated patient safety score. Using linear correlation, we calculated the association between the 2 summary safety measures (overall patient safety rating and aggregated patient safety score) and 2 composite quality measures, a chronic disease score, and a prevention score. The survey response rate was 79% (387/492). There was considerable variation in both safety culture scores and quality scores from office to office. There was no association between the chronic disease score and either summary measure of safety culture. There were small but statistically significant negative associations between the prevention score and the overall patient safety rating (β = -0.087, P = 0.002) as well as the aggregated patient safety score (β = -0.004, P = 0.007). Although safety theory predicts a positive association between safety culture and quality, we found no meaningful associations between safety culture and currently accepted measures of primary care clinical quality. Larger studies across several health care organizations are needed to determine whether these findings are reproducible. If so, it may be necessary to reconsider the dimensions of safety culture in primary care as well as the relationship between safety culture and primary care clinical quality.

  15. Generation of Requirements for Simulant Measurements

    NASA Technical Reports Server (NTRS)

    Rickman, D. L.; Schrader, C. M.; Edmunson, J. E.

    2010-01-01

    This TM presents a formal, logical explanation of the parameters selected for the figure of merit (FoM) algorithm. The FoM algorithm is used to evaluate lunar regolith simulant. The objectives, requirements, assumptions, and analysis behind the parameters are provided. A requirement is derived to verify and validate simulant performance versus lunar regolith from NASA s objectives for lunar simulants. This requirement leads to a specification that comparative measurements be taken the same way on the regolith and the simulant. In turn, this leads to a set of nine criteria with which to evaluate comparative measurements. Many of the potential measurements of interest are not defensible under these criteria. For example, many geotechnical properties of interest were not explicitly measured during Apollo and they can only be measured in situ on the Moon. A 2005 workshop identified 32 properties of major interest to users. Virtually all of the properties are tightly constrained, though not predictable, if just four parameters are controlled. Three parameters (composition, size, and shape) are recognized as being definable at the particle level. The fourth parameter (density) is a bulk property. In recent work, a fifth parameter (spectroscopy) has been identified, which will need to be added to future releases of the FoM.

  16. Statistical Analysis and Modeling of Occupancy Patterns in Open-Plan Offices using Measured Lighting-Switch Data

    SciTech Connect

    Chang, Wen-Kuei; Hong, Tianzhen

    2013-01-01

    Occupancy profile is one of the driving factors behind discrepancies between the measured and simulated energy consumption of buildings. The frequencies of occupants leaving their offices and the corresponding durations of absences have significant impact on energy use and the operational controls of buildings. This study used statistical methods to analyze the occupancy status, based on measured lighting-switch data in five-minute intervals, for a total of 200 open-plan (cubicle) offices. Five typical occupancy patterns were identified based on the average daily 24-hour profiles of the presence of occupants in their cubicles. These statistical patterns were represented by a one-square curve, a one-valley curve, a two-valley curve, a variable curve, and a flat curve. The key parameters that define the occupancy model are the average occupancy profile together with probability distributions of absence duration, and the number of times an occupant is absent from the cubicle. The statistical results also reveal that the number of absence occurrences decreases as total daily presence hours decrease, and the duration of absence from the cubicle decreases as the frequency of absence increases. The developed occupancy model captures the stochastic nature of occupants moving in and out of cubicles, and can be used to generate a more realistic occupancy schedule. This is crucial for improving the evaluation of the energy saving potential of occupancy based technologies and controls using building simulations. Finally, to demonstrate the use of the occupancy model, weekday occupant schedules were generated and discussed.

  17. Relationships Among Stress Measures, Risk Factors, and Inflammatory Biomarkers in Law Enforcement Officers

    PubMed Central

    Ramey, Sandra L.; Downing, Nancy R.; Franke, Warren D.; Perkhounkova, Yelena; Alasagheirin, Mohammad H.

    2011-01-01

    Law enforcement officers suffer higher morbidity and mortality rates from all causes than the general population. Cardiovascular disease (CVD) accounts for a significant portion of the excess illness, with a reported prevalence as high as 1.7 times that of the general population. To determine which occupational hazards cause this increased risk and morbidity, it is imperative to study law enforcement officers before they retire. The long-range goal of our research is to reduce the incidence of CVD-related illness and death among aging law enforcement officers. The purpose of the present study was to measure pro- and anti-atherogenic inflammatory markers in blood samples from law enforcement officers (n = 71) and determine what types of occupation-related stress correlate with differences in these markers. For each outcome variable of interest, we developed separate regression models. Two groups of potential predictors were examined for inclusion in the models. Selected measures of stress were examined for inclusion in the models, in addition to general covariates, such as gender, ethnicity, years in law enforcement, and body mass index. Our results revealed statistically significant relationships between several physiologic variables and measures of stress. PMID:21362637

  18. Simulation of HLNC and NCC measurements

    SciTech Connect

    Lu, Ming-Shih; Teichmann, T.; De Ridder, P.

    1994-03-01

    This report discusses an automatic method of simulating the results of High Level Neutron Coincidence Counting (HLNC) and Neutron Collar Coincidence Counting (NCC) measurements to facilitate the safeguards` inspectors understanding and use of these instruments under realistic conditions. This would otherwise be expensive, and time-consuming, except at sites designed to handle radioactive materials, and having the necessary variety of fuel elements and other samples. This simulation must thus include the behavior of the instruments for variably constituted and composed fuel elements (including poison rods and Gd loading), and must display the changes in the count rates as a function of these characteristics, as well as of various instrumental parameters. Such a simulation is an efficient way of accomplishing the required familiarization and training of the inspectors by providing a realistic reproduction of the results of such measurements.

  19. Correlation between pedometer and the Global Physical Activity Questionnaire on physical activity measurement in office workers

    PubMed Central

    2014-01-01

    Background This study aimed to examine the correlation of physical activity levels assessed by pedometer and those by the Global Physical Activity Questionnaire (GPAQ) in a population of office workers. Methods A cross-sectional study was conducted on 320 office workers. A self-administered questionnaire was distributed to each office worker by hand. Physical activity level was objectively assessed by a pedometer for 7 consecutive days and subjectively assessed by the GPAQ. Based on the pedometer and GPAQ outcomes, participants were classified into 3 groups: inactive, moderately active, and highly active. Results No correlation in the physical activity level assessed by the pedometer and GPAQ was found (rs = .08, P = 0.15). When considering the pedometer as the criterion for comparison, 65.3% of participants had underestimated their physical activity level using the GPAQ, whereas 9.3% of participants overestimated their physical activity level. Conclusions Physical activity level in office workers assessed by a subjective measure was greatly different from assessed by an objective tool. Consequently, research on physical activity level, especially in those with sedentary lifestyle, should consider using an objective measure to ensure that it closely reflects a person’s physical activity level. PMID:24886593

  20. TE/TM Simulations of Interferometric Measurements

    NASA Technical Reports Server (NTRS)

    Houshmand, Bijan

    2000-01-01

    Interferometric synthetic aperture radar (IFSAR) measurements at X-, C-, L-, and P-band are used to derive ground topography at meter level resolution. Interpretation of the derived topography requires attention due to the complex interaction of the radar signal with ground cover. The presence of penetrable surfaces such as vegetation, and tree canopies poses a challenge since the depth of penetration depends on a number of parameters such as the operating radar frequency, polarization, incident angle, as well as terrain structure. The dependence of the reconstructed topography on polarization may lead to the characterization of the ground cover. Simulation of interferometric measurements is useful for interpretation of the derived topography (B. Houshmand, Proceedings of URSI, 314, 1997). In this talk , time domain simulations for interferometric measurement for TE- and TM- polarization are presented. Time domain simulation includes the effects of the surface material property as well geometry comparable the radar signal wavelength (B. Houshmand, Proceedings of the URSI, 25, 1998). The IFSAR simulation is carried out in two steps. First, the forward scattering data is generated based on full wave analysis. Next, the electromagnetic information is inverted to generate surface topography. This inversion is based on the well known IFSAR processing technique which is composed of signal compression, and formation of an interferogram. The full wave forward scattering data is generated by the scattered-field formulation of the FDTD algorithm. The simulation is carried out by exciting the computational domain by a radar signal. The scattered field is then computed and translated to the receiving interferometric antennas using the time-domain Huygen's principle. The inversion process starts by compressing the time-domain data. The range compressed data from both receivers are then coregistered to form an interferogram. The resulting interferogram is then related to the

  1. Simulations for the Development of Thermoelectric Measurements

    NASA Astrophysics Data System (ADS)

    Zabrocki, Knud; Ziolkowski, Pawel; Dasgupta, Titas; de Boor, Johannes; Müller, Eckhard

    2013-07-01

    In thermoelectricity, continuum theoretical equations are usually used for the calculation of the characteristics and performance of thermoelectric elements, modules or devices as a function of external parameters (material, geometry, temperatures, current, flow, load, etc.). An increasing number of commercial software packages aimed at applications, such as COMSOL and ANSYS, contain vkernels using direct thermoelectric coupling. Application of these numerical tools also allows analysis of physical measurement conditions and can lead to specifically adapted methods for developing special test equipment required for the determination of TE material and module properties. System-theoretical and simulation-based considerations of favorable geometries are taken into account to create draft sketches in the development of such measurement systems. Particular consideration is given to the development of transient measurement methods, which have great advantages compared with the conventional static methods in terms of the measurement duration required. In this paper the benefits of using numerical tools in designing measurement facilities are shown using two examples. The first is the determination of geometric correction factors in four-point probe measurement of electrical conductivity, whereas the second example is focused on the so-called combined thermoelectric measurement (CTEM) system, where all thermoelectric material properties (Seebeck coefficient, electrical and thermal conductivity, and Harman measurement of zT) are measured in a combined way. Here, we want to highlight especially the measurement of thermal conductivity in a transient mode. Factors influencing the measurement results such as coupling to the environment due to radiation, heat losses via the mounting of the probe head, as well as contact resistance between the sample and sample holder are illustrated, analyzed, and discussed. By employing the results of the simulations, we have developed an

  2. Automated measurement of office, home and ambulatory blood pressure in atrial fibrillation.

    PubMed

    Kollias, Anastasios; Stergiou, George S

    2014-01-01

    1. Hypertension and atrial fibrillation (AF) often coexist and are strong risk factors for stroke. Current guidelines for blood pressure (BP) measurement in AF recommend repeated measurements using the auscultatory method, whereas the accuracy of the automated devices is regarded as questionable. This review presents the current evidence on the feasibility and accuracy of automated BP measurement in the presence of AF and the potential for automated detection of undiagnosed AF during such measurements. 2. Studies evaluating the use of automated BP monitors in AF are limited and have significant heterogeneity in methodology and protocols. Overall, the oscillometric method is feasible for static (office or home) and ambulatory use and appears to be more accurate for systolic than diastolic BP measurement. 3. Given that systolic hypertension is particularly common and important in the elderly, the automated BP measurement method may be acceptable for self-home and ambulatory monitoring, but not for professional office or clinic measurement. 4. An embedded algorithm for the detection of asymptomatic AF during routine automated BP measurement with high diagnostic accuracy has been developed and appears to be a useful screening tool for elderly hypertensives.

  3. Computational simulation of Faraday probe measurements

    NASA Astrophysics Data System (ADS)

    Boerner, Jeremiah J.

    Electric propulsion devices, including ion thrusters and Hall thrusters, are becoming increasingly popular for long duration space missions. Ground-based experimental testing of such devices is performed in vacuum chambers, which develop an unavoidable background gas due to pumping limitations and facility leakage. Besides directly altering the operating environment, the background gas may indirectly affect the performance of immersed plasma probe diagnostics. This work focuses on computational modeling research conducted to evaluate the performance of a current-collecting Faraday probe. Initial findings from one dimensional analytical models of plasma sheaths are used as reference cases for subsequent modeling. A two dimensional, axisymmetric, hybrid electron fluid and Particle In Cell computational code is used for extensive simulation of the plasma flow around a representative Faraday probe geometry. The hybrid fluid PIC code is used to simulate a range of inflowing plasma conditions, from a simple ion beam consistent with one dimensional models to a multiple component plasma representative of a low-power Hall thruster plume. These simulations produce profiles of plasma properties and simulated current measurements at the probe surface. Interpretation of the simulation results leads to recommendations for probe design and experimental techniques. Significant contributions of this work include the development and use of two new non-neutral detailed electron fluid models and the recent incorporation of multi grid capabilities.

  4. Prototypes of Cognitive Measures for Air Force Officers: Test Development and Item Banking

    DTIC Science & Technology

    1990-05-01

    AFHRL-TP-89-737 3, COPY AIR FORCE PROTOTYPES OF COGNITIVE MEASURES FOR AIR FORCE OFFICERS: TEST DEVELOPMENT AND ITEM BANKING DTIC f1 ELECTF H Frances...Jacobina Skinner MANPOWER AND PERSONNEL DIVISION R Brooks Air Force Base, Texas 78235-5601 E S O May 1990U Final Technical Paper for Period September 1987...November 1989 R C Approved for public release; distribution is unlimited. E S LABORATORY AIR FORCE SYSTEMS COMMAND BROOKS AIR FORCE BASE, TEXAS

  5. Prevalence of masked uncontrolled hypertension according to the number of office blood pressure measurements.

    PubMed

    Vinyoles, E; Camafort, M; Domenech, M; Coca, A; Sobrino, J

    2015-11-01

    The reported prevalence of masked uncontrolled hypertension (MUCH) varies because many studies are not comparable as they use different measurement methodologies. To evaluate the influence of the number of office blood pressure readings on the prevalence of MUCH we conducted a cross-sectional, multicenter study in treated hypertensive patients. We carried out an observational, cross-sectional, multicenter study in 33 Spanish hospital-based hypertension units, involving 35 investigators and 12 Autonomous Communities. Six blood pressure readings and a 24-h ambulatory blood pressure monitoring were performed in treated hypertensive patients. The means of the first 3 readings (P123), the 2nd, 3rd and 4th readings (P234), the 3rd, 4th and 5th readings (P345) and the last 3 readings (P456) were compared with mean 24-h blood pressure. MUCH was defined as office blood pressure <140/90mmHg and 24-h blood pressure ≥130/80mmHg, considering the first 3 readings (MUCH123), the 2nd, 3rd and 4th readings (MUCH234), the 3rd, 4th and 5th readings (MUCH345) and the last 3 readings (MUCH456). We included 498 hypertensive patients. Mean (standard deviation) office blood pressure measurements were: (P123) 141(18)/82(11); (P234) 139(17)/81(11); (P345) 138(17)/81(11) and (P456) 137(16)/80(10) mmHg. Mean 24-h blood pressure was 127(13.8)/75(9.5) mmHg. The correlation coefficients between ambulatory and office systolic/diastolic blood pressure were (P123):0.48/0.50; (P234):0.50/0.52; (P345):0.50/0.54; and (P456):0.50/0.55 (p<0.001, all). The prevalences of MUCH123, MUCH234, MUCH345 and MUCH456 were 14.5%, 18.9%, 19.5% and 21.1%, respectively. The prevalence of MUCH diagnosis depends on the serial office blood pressure readings, being much higher for the last three blood pressure readings. Discarding the first and second office blood pressure measures seems to be the most accurate method for diagnosing MUCH. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Medicina

  6. Control over the Scheduling of Simulated Office Work Reduces the Impact of Workload on Mental Fatigue and Task Performance

    ERIC Educational Resources Information Center

    Hockey, G. Robert J.; Earle, Fiona

    2006-01-01

    Two experiments tested the hypothesis that task-induced mental fatigue is moderated by control over work scheduling. Participants worked for 2 hr on simulated office work, with control manipulated by a yoking procedure. Matched participants were assigned to conditions of either high control (HC) or low control (LC). HC participants decided their…

  7. Strategies for classifying patients based on office, home, and ambulatory blood pressure measurement.

    PubMed

    Zhang, Lu; Li, Yan; Wei, Fang-Fei; Thijs, Lutgarde; Kang, Yuan-Yuan; Wang, Shuai; Xu, Ting-Yan; Wang, Ji-Guang; Staessen, Jan A

    2015-06-01

    Hypertension guidelines propose home or ambulatory blood pressure monitoring as indispensable after office measurement. However, whether preference should be given to home or ambulatory monitoring remains undetermined. In 831 untreated outpatients (mean age, 50.6 years; 49.8% women), we measured office (3 visits), home (7 days), and 24-h ambulatory blood pressures. We applied hypertension guidelines for cross-classification of patients into normotension or white-coat, masked, or sustained hypertension. Based on office and home blood pressures, the prevalence of white-coat, masked, and sustained hypertension was 61 (10.3%), 166 (20.0%), and 162 (19.5%), respectively. Using daytime (from 8 am to 6 pm) instead of home blood pressure confirmed the cross-classification in 575 patients (69.2%), downgraded risk from masked hypertension to normotension (n=24) or from sustained to white-coat hypertension (n=9) in 33 (4.0%), but upgraded risk from normotension to masked hypertension (n=179) or from white-coat to sustained hypertension (n=44) in 223 (26.8%). Analyses based on 24-h ambulatory blood pressure were confirmatory. In adjusted analyses, both the urinary albumin-to-creatinine ratio (+20.6%; confidence interval, 4.4-39.3) and aortic pulse wave velocity (+0.30 m/s; confidence interval, 0.09-0.51) were higher in patients who moved up to a higher risk category. Both indexes of target organ damage and central augmentation index were positively associated (P≤0.048) with the odds of being reclassified. In conclusion, for reliably diagnosing hypertension and starting treatment, office measurement should be followed by ambulatory blood pressure monitoring. Using home instead of ambulatory monitoring misses the high-risk diagnoses of masked or sustained hypertension in over 25% of patients.

  8. Crystalline lens MTF measurement during simulated accommodation

    NASA Astrophysics Data System (ADS)

    Borja, David; Takeuchi, Gaku; Ziebarth, Noel; Acosta, Ana C.; Manns, Fabrice; Parel, Jean-Marie

    2005-04-01

    Purpose: To design and test an optical system to measure the optical quality of post mortem lenses during simulated accommodation. Methods: An optical bench top system was designed to measure the point spread function and calculate the modulation transfer function (MTF) of monkey and human ex-vivo crystalline lenses. The system consists of a super luminescent diode emitting at 850nm, collimated into a 3mm beam which is focused by the ex-vivo lens under test. The intensity distribution at the focus (point spread function) is re-imaged and magnified onto a beam profiler CCD camera. The optical quality in terms of spatial frequency response (modulation transfer function) is calculated by Fourier transform of the point spread function. The system was used on ex-vivo lenses with attached zonules, ciliary body and sclera. The sclera was glued to 8 separate PMMA segments and stretched radial by 5mm on an accommodation simulating lens stretching device. The point spread function was measured for each lens in the relaxed and stretched state for 5 human (ages 38-86 years) and 5 cynomolgus monkey (ages 53 - 67 months) fresh post mortem crystalline lenses. Results: Stretching induced measurable changes in the MTF. The cutoff frequency increased from 54.4+/-13.6 lp/mm unstretched to 59.5+/-21.4 lp/mm stretched in the post-presbyopic human and from 51.9+/-24.7 lp/mm unstretched to 57.7+/-18.5 lp/mm stretched cynomolgus monkey lenses. Conclusion: The results demonstrate the feasibility of measuring the optical quality of ex-vivo human and cynomolgus monkey lenses during simulated accommodation. Additional experiments are underway to quantify changes in optical quality induced by stretching.

  9. Practice simulated office orals as a predictor of Certification examination performance in family medicine.

    PubMed

    Noel, Kendall; Archibald, Douglas; Brailovsky, Carlos

    2017-04-01

    To determine if performance on practice simulated office orals (SOOs) conducted during residency training could predict residents' performance on the SOO component of the College of Family Physicians of Canada's (CFPC's) final Certification examination. Prospective cohort study. University of Ottawa in Ontario. Family medicine residents enrolled in the University of Ottawa's Family Medicine Residency program between July 1, 2012, and June 30, 2014, who were eligible to write the CFPC Certification examination in the spring of 2014 and who had participated in all 4 practice SOO examination sessions; 23 residents met these criteria. Scores on practice SOO sessions during fall 2012, spring 2013, fall 2013, and spring 2014; and the SOO component score on the spring 2014 administration of the CFPC Certification examination. Weighted least squares regression analysis using the 4 practice SOO session scores significantly predicted the final Certification examination SOO score (P < .05), with an adjusted R(2) value of 0.29. Additional analysis revealed that the mean scores for the cohort generated at each time point were statistically different from each other (P < .001) and that the relationship over time could be represented by either a linear relationship or a quadratic relationship. A generalizability study generated a relative generalizability coefficient of 0.63. Our results confirm the usefulness of practice SOOs as a progress test and demonstrate the feasibility of using them to predict final scores on the SOO component of the CFPC's Certification examination. Copyright© the College of Family Physicians of Canada.

  10. A proposal to change the Office of Science injury reduction contractual performance measures

    SciTech Connect

    Griffing, William J.; /Fermilab

    2005-06-01

    All ten of the Office of Science (SC) national laboratories have made significant progress in transforming the safety culture of their organizations over the last five to 10 years. The gradual downward trend in injury rates at each of these laboratories is evidence of this transformation. The present practice of inserting uniform injury-reduction metrics into each SC laboratory's contract, despite our differences, and attempting to measure that performance with limited sampling data, however, does not result in accurate assessments of performance. This paper offers an alternative approach to performance measurement.

  11. Cardiovascular Risk in Hypertension in Relation to Achieved Blood Pressure Using Automated Office Blood Pressure Measurement.

    PubMed

    Myers, Martin G; Kaczorowski, Janusz; Dolovich, Lisa; Tu, Karen; Paterson, J Michael

    2016-10-01

    The SPRINT (Systolic Blood Pressure Intervention Trial) reported that some older, higher risk patients might benefit from a target systolic blood pressure (BP) of <120 versus <140 mm Hg. However, it is not yet known how the BP target and measurement methods used in SPRINT relate to cardiovascular outcomes in real-world practice. SPRINT used the automated office BP technique, which requires the patient to be resting quietly and alone, with multiple readings being recorded automatically using an electronic oscillometric sphygmomanometer. We studied the relationship between achieved automated office BP at baseline and cardiovascular events in 6183 community-dwelling residents of Ontario aged ≥66 years who were receiving antihypertensive therapy and followed for a mean of 4.6 years. Adjusted hazard ratios (95% confidence intervals) were computed for 10 mm Hg increments in achieved automated office BP at baseline using Cox proportional hazards regression and the BP category with the lowest event rate as the reference category. Based on 904 fatal and nonfatal cardiovascular events, the nadir of cardiovascular events was at the systolic pressure category of 110 to 119 mm Hg, which was lower than the next highest category of 120 to 129 mm Hg (hazard ratio 1.30 [1.01, 1.66]). The hazard ratio for diastolic pressure was relatively unchanged above 60 mm Hg. Pulse pressure exhibited an increase in hazard ratio (1.33 [1.02, 1.72]) at ≥80 mm Hg. These results using automated office BP measurement in a usual treatment setting extend the finding in SPRINT of an optimum target systolic BP of <120 mm Hg to routine clinical practice. © 2016 American Heart Association, Inc.

  12. An Exploratory Energy Analysis of Electrochromic Windows in Small and Medium Office Buildings - Simulated Results Using EnergyPlus

    SciTech Connect

    Belzer, David B.

    2010-08-01

    The Department of Energy’s (DOE) Building Technologies Program (BTP) has had an active research program in supporting the development of electrochromic (EC) windows. Electrochromic glazings used in these windows have the capability of varying the transmittance of light and heat in response to an applied voltage. This dynamic property allows these windows to reduce lighting, cooling, and heating energy in buildings where they are employed. The exploratory analysis described in this report examined three different variants of EC glazings, characterized by the amount of visible light and solar heat gain (as measured by the solar heat gain coefficients [SHGC] in their “clear” or transparent states). For these EC glazings, the dynamic range of the SHGC’s between their “dark” (or tinted) state and the clear state were: (0.22 - 0.70, termed “high” SHGC); (0.16 - 0.39, termed “low” SHGC); and (0.13 - 0.19; termed “very low” SHGC). These glazings are compared to conventional (static) glazing that meets the ASHRAE Standard 90.1-2004 energy standard for five different locations in the U.S. All analysis used the EnergyPlus building energy simulation program for modeling EC windows and alternative control strategies. The simulations were conducted for a small and a medium office building, where engineering specifications were taken from the set of Commercial Building Benchmark building models developed by BTP. On the basis of these simulations, total source-level savings in these buildings were estimated to range between 2 to 7%, depending on the amount of window area and building location.

  13. Recommendations for blood pressure measuring devices for office/clinic use in low resource settings.

    PubMed

    Parati, Gianfranco; Mendis, Shanthi; Abegunde, Dele; Asmar, Ronald; Mieke, Stephan; Murray, Alan; Shengelia, Bakuti; Steenvoorden, Gijs; Van Montfrans, Gert; O'Brien, Eoin

    2005-02-01

    This paper, which summarizes the conclusions of a WHO Expert meeting, is aimed at proposing indications to develop technical specifications for an accurate and affordable blood pressure measuring device for office/clinic use in low resource settings. Blood pressure measuring devices to be used in low resource settings should be accurate, affordable, and easily available worldwide. Given the serious inherent inaccuracy of the auscultatory technique, validated and affordable electronic devices, that have the option to select manual readings, seem to be a suitable solution for low resource settings. The agreement on the technical specifications for automated blood pressure measuring devices for office/clinic use in low resource settings included the following features: high accuracy, adoption of electronic transducers and solar batteries for power supply, standard rates of cuff inflation and deflation, adequate cuff size, digital display powered by solar batteries, facilities for adequate calibration, environmental requirements, no need of memory function, resistance to shock and temperature changes, and low cost. Availability of a device with these features should be accompanied by adequate training of health care personnel, who should guarantee implementation of the procedures recommended in recent European and American Guidelines for accurate blood pressure measurement.

  14. Are pressure measurements effective in the assessment of office chair comfort/discomfort? A review.

    PubMed

    Zemp, Roland; Taylor, William R; Lorenzetti, Silvio

    2015-05-01

    Nowadays, the majority of jobs in the western world involves sitting in an office chair. As a result, a comfortable and supported sitting position is essential for employees. In the literature, various objective methods (e.g. pressure measurements, measurements of posture, EMG etc.) have been used to assess sitting comfort/discomfort, but their validity remains unknown. This review therefore examines the relationship between subjective comfort/discomfort and pressure measurements while sitting in office chairs. The literature search resulted in eight papers that met all our requirements. Four studies identified a relationship between subjective comfort/discomfort and pressure distribution parameters (including correlations of up to r = 0.7 ± 0.13). However, the technique for evaluating subjective comfort/discomfort seems to play an important role on the results achieved, therefore placing their validity into question. The peak pressure on the seat pan, the pressure distribution on the backrest and the pressure pattern changes (seat pan and backrest) all appear to be reliable measures for quantifying comfort or discomfort.

  15. In Situ Measurement Activities at the NASA Orbital Debris Program Office

    NASA Technical Reports Server (NTRS)

    Liou, J.-C.; Burchell, M.; Corsaro, R.; Drolshagen, G.; Giovane, F.; Pisacane, V.; Stansbery, E.

    2009-01-01

    The NASA Orbital Debris Program Office has been involved in the development of several particle impact instruments since 2003. The main objective of this development is to eventually conduct in situ measurements to better characterize the small (millimeter or smaller) orbital debris and micrometeoroid populations in the near-Earth environment. In addition, the Office also supports similar instrument development to define the micrometeoroid and lunar secondary ejecta environment for future lunar exploration activities. The instruments include impact acoustic sensors, resistive grid sensors, fiber optic displacement sensors, and impact ionization sensors. They rely on different mechanisms and detection principles to identify particle impacts. A system consisting of these different sensors will provide data that are complimentary to each other, and will provide a better description of the physical and dynamical properties (e.g., size, mass, and impact speed) of the particles in the environment. Details of several systems being considered by the Office and their intended mission objectives are summarized in this paper.

  16. In Situ Measurement Activities at the Nasa Orbital Debris Program Office

    NASA Technical Reports Server (NTRS)

    Liou, J.-C.; Burchell, M.; Corsaro, R.; Drolshagen, G.; Giovane, F.; Pisacane, V.; Stansbery, E.

    2009-01-01

    The NASA Orbital Debris Program Office has been involved in the development of several particle impact instruments since 2003. The main objective of this development is to eventually conduct in situ measurements to better characterize the small (millimeter or smaller) orbital debris and micrometeoroid populations in the near-Earth environment. In addition, the Office also supports similar instrument development to define the micrometeoroid and lunar secondary ejecta environment for future lunar exploration activities. The instruments include impact acoustic sensors, resistive grid sensors, fiber optic displacement sensors, and impact ionization sensors. They rely on different mechanisms and detection principles to identify particle impacts. A system consisting of these different sensors will provide data that are complimentary to each other, and will provide a better description of the physical and dynamical properties (e.g., size, mass, and impact speed) of the particles in the environment. Details of several systems being considered by the Office and their intended mission objectives are summarized in this paper.

  17. Measurement of Axial Length in an Office Setting Versus Under General Anesthesia in Infants and Toddlers: A Comparative Study.

    PubMed

    Kinori, Michael; Fabian, Ido Didi; Spierer, Abraham; Wygnanski-Jaffe, Tamara; Robbins, Shira L; Granet, David B; Ben Zion, Itay

    2015-01-01

    To examine whether axial length measurement in awake infants and toddlers is feasible, and whether there is a difference in axial length measurement between an office setting and under general anesthesia. This prospective comparative case study was conducted at the Goldschleger Eye Institute, Sheba Medical Center, Israel. Using the same instruments, axial length measurements were obtained using a standard applanation technique twice: once in an office setting when the infant/toddler was awake and once under general anesthesia in the operating room. A paired t test was used to test for differences between measurements. Thirty-three eyes of 19 participants younger than 28 months were examined; 24 (73%) eyes had cataracts and the remainder had clear lenses. One child was excluded from the study due to lack of cooperation during axial length measurement in the office setting and another due to the lengthy gap between measurements. Of the remaining 31 children, the average age was 9 months. Average axial length measurements were shorter by 0.12 mm in the office setting than under general anesthesia (P = .14). No adverse effects were observed after axial length measurements in the office setting. Axial length measurement in an office setting is generally reasonable to obtain. The results showed no significant difference in the axial length measured in the two settings. Copyright 2015, SLACK Incorporated.

  18. Evaluating the Met Office Unified Model simulated land surface temperature (LST) using a multi-platform approach

    NASA Astrophysics Data System (ADS)

    Brooke, Jennifer; Harlow, Chawn; Best, Martin; Newman, Stuart; Scott, Russell; Edwards, John; Thelen, Jean-Claude; Pavelin, Ed; Weeks, Mark

    2015-04-01

    The Met Office Unified Model (UM) has a significant cold bias in land surface temperature (LST) in semi-arid regions at global resolution, and limited area 4.4 km and 2.2 km configurations. The daytime LST cold bias simulated by the JULES land surface scheme within the UM is present throughout the annual cycle in semi-arid regions of the globe in comparison to IASI retrievals. These errors are largest in late spring and early summer and have magnitudes of 5 to 15 K, dependent on model resolution. This work will show verification of model biases through ground-based, in-situ airborne and satellite observations during the Semi-Arid Land Surface Temperature and IASI Calibration Experiment (SALSTICE) in semi-arid south-eastern Arizona in May 2013. Airborne observations of LST from the FAAM research aircraft using the Airborne Research Interferometer Evaluation System (ARIES) were used to investigate the spatial distribution of the model errors and evaluate IASI retrievals. Airborne retrievals of surface temperature were found to broadly agree with IASI retrievals; uncertainties are attributed to the spatial variability in the ARIES measurements compared with the IASI footprints and due to differences within the retrieval, such as assumed emissivity. The UM errors in LST were found to vary with model resolution as well as topographic complexity, with the coarse resolution global model having larger errors than the limited area models. Regions with complex terrain had the highest LST errors while the errors over the less complex basins were lower, in the range of 4-5 K. Evaluation of the JULES land surface scheme has been performed for flux tower sites in the Walnut Gulch Experimental Watershed in south-eastern Arizona. An annual dataset of flux tower measurements confirms the LST biases seen with aircraft and satellite observations and indicates that night-time LST biases are of the order of those observed during the day. Comparisons of different model resolutions show

  19. Volatilization of EPTC: Simulation and measurement

    SciTech Connect

    Baker, J.M.; Koskinen, W.C.; Dowdy, R.H.

    1996-01-01

    Many of the organic chemicals used in agricultural production are susceptible to loss from the soil surface to the atmosphere by volatilization. Adequate prediction of the impact of these chemicals on the environment thus requires consideration of both downward movement through the soil to groundwater and upward movement in the gas phase to the atmosphere. We developed a method to mechanistically simulate volatilization within the framework of a conventionally formulated solute transport model and used it to simulate the gas-phase losses of EPTC, a commonly used volatile herbicide. The model considers efflux of a trace gas at the sod surface to be a process of unsteady diffusion, interrupted intermittently by dispersive events that can be thought of as eddies at the innermost scale. Model results were compared to measurements of volatilization during the first 7 d following application of EPTC, conducted with a Bowen ratio system in a 17-ha field at Rosemount, MN. The measurements indicated a relatively large initial flux (ca. 150 g ha{sup -1} h{sup -1}) that rapidly decreased to negligible levels within a day following application. The model agreed reasonably well on the first day, if a measured value for Henry`s constant was used rather than a value estimated from the saturation vapor pressure and the solubility. However, on subsequent days the model considerably overestimated volatilization, regardless of the Henry`s constant that was used. It is likely that hysteresis in sorption/desorption, particularly as surface soil dries following herbicide incorporation, may be the primary reason why volatile losses are lower than might be predicted on the basis of equilibrium partitioning theory. 42 refs., 5 figs., 1 tab.

  20. Measurements of Simulated Micrometeoroids in the Laboratory

    NASA Astrophysics Data System (ADS)

    Munsat, T.; Thomas, E.; DeLuca, M. D.; Horanyi, M.; Janches, D.; Sternovsky, Z.

    2016-12-01

    Each day, several tons of meteoric material enters Earth's atmosphere. The majority of this material consists of small dust particles that completely or partially ablate at high altitudes, producing metallic layers in the atmosphere with a density peak at around 85-95 km with 20 km vertical extent. This large influx of dust particles has been suggested to play a role in a variety of atmospheric phenomena including: layers of metal atoms and ions, nucleation of noctilucent clouds, and effects on stratospheric aerosols and O3 chemistry. Meteor radars provide one method of measuring these dust particles and are sensitive to the most important mass regime in terms of daily mass input (10-9 - 10-3 g). However, there are uncertainties in the ablation process which lead to uncertainties in the radar measurements. The dust accelerator facility at the Institute for Modeling Plasma, Atmospheres and Cosmic Dust (IMPACT) has implemented an experiment that allows for the simulation of micrometeoroid ablation in the laboratory. A pressurized ablation chamber is fitted to the end of the dust accelerator and acts as a proxy atmosphere for the accelerated dust particles. The design of the ablation chamber expands on previous experimental efforts and contains a suite of electronics capable of measuring the generated plasma along the entire ablation trajectory with a spatial resolution of 2.6 cm. This allows for a direct measurement of the ionization coefficient, β, which is a critical parameter for interpreting radar measurements. It also allows for the verification of the basic physics in commonly used ablation models. Here we report on new measurements of the ionization coefficient for iron micrometeoroids. Our results indicate that the commonly used analytical β(v) curves are correct except for high-speed, interstellar meteors. We also present comparisons between laboratory ablation profiles and predictions from ablation physics models.

  1. Home and Office Blood Pressure Control among Treated Hypertensive Patients in Japan: Findings from the Japan Home versus Office Blood Pressure Measurement Evaluation (J-HOME) Study

    PubMed Central

    Obara, Taku; Ohkubo, Takayoshi; Satoh, Michihiro; Mano, Nariyasu; Imai, Yutaka

    2010-01-01

    Appropriate control of blood pressure (BP) is essential for prevention of future cardiovascular events. However, BP control among treated hypertensive patients has been insufficient. Recently, the usefulness of self-measured BP at home (home BP measurement) for the management of hypertension has been reported in many studies. We evaluated BP control both at home and in the office among treated hypertensive patients in primary care settings in Japan (the J-HOME study). We found poor control of home and office BPs and clarified some factors affecting control. We also examined factors associated with the magnitude of the white-coat effect, the morning–evening BP difference, and home heart rate in this J-HOME study. PMID:27713260

  2. Beam ion instability: Measurement, analysis, and simulation

    SciTech Connect

    Wang, L.; Safranek, J.; Cai, Y.; Corbett, J.; Hettel, B.; Raubenheimer, T. O.; Schmerge, J.; Sebek, J.; /SLAC

    2013-10-03

    A weak vertical coupled-bunch instability with oscillation amplitude of the order of a few μ m has been observed in SPEAR3 at nominal vacuum pressure. The instability becomes stronger with increasing neutral gas pressure as observed by turning off vacuum pumps, and becomes weaker when the vertical beam emittance is increased. These observations indicate that the vertical beam motion is driven by ions trapped in the periodic potential of the electron beam. In this paper we present a series of comprehensive beam measurements, impedance-based stability analysis, and numerical simulations of beam-ion interactions in SPEAR3. The effects of vacuum pressure, gas species, beam current, bunch fill pattern, chromaticity, and vertical beam emittance are investigated.

  3. Measurement of functional capacity requirements of police officers to aid in development of an occupation-specific cardiac rehabilitation training program

    PubMed Central

    Schneider, Jonna; Hubbard, Matthew; McCullough-Shock, Tiffany; Cheng, Dunlei; Simms, Kay; Hartman, Julie; Hinton, Paul; Strauss, Danielle

    2010-01-01

    This study was designed to measure the functional capacity of healthy subjects during strenuous simulated police tasks, with the goal of developing occupation-specific training for cardiac rehabilitation of police officers. A calibrated metabolic instrument and an oxygen consumption data collection mask were used to measure the oxygen consumption and heart rates of 30 Dallas Police Academy officers and cadets as they completed an 8-event obstacle course that simulated chasing, subduing, and handcuffing a suspect. Standard target heart rates (85% of age-predicted maximum heart rate, or 0.85 × [220 – age]) and metabolic equivalents (METs) were calculated; a matched-sample t test based on differences between target and achieved heart rate and MET level was used for statistical analysis. Peak heart rates during the obstacle course simulation were significantly higher than the standard target heart rates (those at which treadmill stress tests in physicians' offices are typically stopped) (t29 = 12.81, P < 0.001) and significantly higher than the suggested maximum of 150 beats/min during cardiac rehabilitation training (t29 = 17.84, P < 0.001). Peak MET levels during the obstacle course simulation were also significantly higher than the goal level (8 METs) that patients typically achieve in a cardiac rehabilitation program (t29 = 14.73, P < 0.001). We conclude that police work requires a functional capacity greater than that typically attained in traditional cardiac rehabilitation programs. Rehabilitation professionals should consider performing maximal stress tests and increasing the intensity of cardiac rehabilitation workouts to effectively train police officers who have had a cardiac event. PMID:20157495

  4. Predictors of Speed Using Off-Ice Measures of College Hockey Players.

    PubMed

    Runner, Aaron R; Lehnhard, Robert A; Butterfield, Stephen A; Tu, Shihfen; OʼNeill, Terrence

    2016-06-01

    The purpose of this study was to examine the relationship between commonly employed dry-land performance tests and skating speed in male collegiate ice hockey players. Forty male National Collegiate Athletic Association Division I hockey players were tested on the following performance variables: vertical jump (VJ), standing broad jump, 40-yard dash, and maximal back squat (SQT). The subjects also performed 3 skating tests: the 90-ft forward acceleration test, the 90-ft backward acceleration test, and the 50-ft flying top speed test (F50). Pearson correlation coefficients were applied to compare the strength of association between each selected off-ice measure and each on-ice measure. Three multiple regression equations were then used to compare the weighted strengths of association between predictor and criterion variables. Only VJ showed significance in relation to skating speed (p = 0.011). These results suggest that meaningful performance testing in ice hockey players should occur mainly on the ice.

  5. Characterization of emissions from a desktop 3D printer and indoor air measurements in office settings.

    PubMed

    Steinle, Patrick

    2016-01-01

    Emissions from a desktop 3D printer based on fused deposition modeling (FDM) technology were measured in a test chamber and indoor air was monitored in office settings. Ultrafine aerosol (UFA) emissions were higher while printing a standard object with polylactic acid (PLA) than with acrylonitrile butadiene styrene (ABS) polymer (2.1 × 10(9) vs. 2.4 × 10(8) particles/min). Prolonged use of the printer led to higher emission rates (factor 2 with PLA and 4 with ABS, measured after seven months of occasional use). UFA consisted mainly of volatile droplets, and some small (100-300 nm diameter) iron containing and soot-like particles were found. Emissions of inhalable and respirable dust were below the limit of detection (LOD) when measured gravimetrically, and only slightly higher than background when measured with an aerosol spectrometer. Emissions of volatile organic compounds (VOC) were in the range of 10 µg/min. Styrene accounted for more than 50% of total VOC emitted when printing with ABS; for PLA, methyl methacrylate (MMA, 37% of TVOC) was detected as the predominant compound. Two polycyclic aromatic hydrocarbons (PAH), fluoranthene and pyrene, were observed in very low amounts. All other analyzed PAH, as well as inorganic gases and metal emissions except iron (Fe) and zinc (Zn), were below the LOD or did not differ from background without printing. A single 3D print (165 min) in a large, well-ventilated office did not significantly increase the UFA and VOC concentrations, whereas these were readily detectable in a small, unventilated room, with UFA concentrations increasing by 2,000 particles/cm(3) and MMA reaching a peak of 21 µg/m(3) and still being detectable in the room even 20 hr after printing.

  6. The Foreign Language Anxiety in a Medical Office Scale: developing and validating a measurement tool for Spanish-speaking individuals.

    PubMed

    Guntzviller, Lisa M; Jensen, Jakob D; King, Andy J; Davis, LaShara A

    2011-09-01

    Communication research has been hindered by a lack of validated measures for Latino populations. To develop and validate a foreign language anxiety in a medical office scale (the Foreign Language Anxiety in a Medical Office Scale [FLAMOS]), the authors conducted a survey of low income, primarily Spanish-speaking Latinos (N=100). The scale factored into a unidimensional construct and showed high reliability (α=.92). The Foreign Language Anxiety in a Medical Office Scale also demonstrated convergent and divergent validity compared with other communication anxiety scales (Personal Report of Communication Apprehension-24, Communication Anxiety Inventory, and Recipient Apprehension Test), and predictive validity for acculturation measures (the Short Acculturation Scale for Hispanics). The Foreign Language Anxiety in a Medical Office Scale provides a validated measure for researchers and may help to explain Latino health care communication barriers.

  7. Large-Scale Hybrid Dynamic Simulation Employing Field Measurements

    SciTech Connect

    Huang, Zhenyu; Guttromson, Ross T.; Hauer, John F.

    2004-06-30

    Simulation and measurements are two primary ways for power engineers to gain understanding of system behaviors and thus accomplish tasks in system planning and operation. Many well-developed simulation tools are available in today's market. On the other hand, large amount of measured data can be obtained from traditional SCADA systems and currently fast growing phasor networks. However, simulation and measurement are still two separate worlds. There is a need to combine the advantages of simulation and measurements. In view of this, this paper proposes the concept of hybrid dynamic simulation which opens up traditional simulation by providing entries for measurements. A method is presented to implement hybrid simulation with PSLF/PSDS. Test studies show the validity of the proposed hybrid simulation method. Applications of such hybrid simulation include system event playback, model validation, and software validation.

  8. Thirty-minute compared to standardised office blood pressure measurement in general practice

    PubMed Central

    Scherpbier-de Haan, Nynke; van der Wel, Mark; Schoenmakers, Gijs; Boudewijns, Steve; Peer, Petronella; van Weel, Chris; Thien, Theo; Bakx, Carel

    2011-01-01

    Background Although blood pressure measurement is one of the most frequently performed measurements in clinical practice, there are concerns about its reliability. Serial, automated oscillometric blood pressure measurement has the potential to reduce measurement bias and white-coat effect' Aim To study agreement of 30-minute office blood pressure measurement (OBPM) with standardised OBPM, and to compare repeatability Design and setting Method comparison study in two general practices in the Netherlands Method Thirty-minute and standardised OBPM was carried out with the same, validated device in 83 adult patients, and the procedure was repeated after 2 weeks. During 30-minute OBPM, blood pressure was measured automatically every 3 minutes, with the patient in a sitting position, alone in a quiet room. Agreement between 30-minute and standardised OBPM was assessed by Bland–Altman analysis. Repeatability of the blood pressure measurement methods after 2 weeks was expressed as the mean difference in combination with the standard deviation of difference (SDD) Results Mean 30-minute OBPM readings were 7.6/2.5 mmHg (95% confidence interval [CI] = 6.1 to 9.1/1.5 to 3.4 mmHg) lower than standardised OBPM readings. The mean difference and SDD between repeated 30-minute OBPMs (mean difference = 3/1 mmHg, 95% CI = 1 to 5/0 to 2 mmHg; SDD 9.5/5.3 mmHg) were lower than those of standardised OBPMs (mean difference = 6/2 mmHg, 95% CI = 4 to 8/1 to 4 mmHg; SDD 10.9/6.3 mmHg). Conclusion Thirty-minute OBPM resulted in lower readings than standardised OBPM and had a better repeatability. These results suggest that 30-minute OBPM better reflects the patient's true blood pressure than standardised OBPM does. PMID:22152748

  9. Extreme precipitation over European river basins in global Met Office Unified Model high-resolution climate simulations

    NASA Astrophysics Data System (ADS)

    Schiemann, Reinhard; Demory, Marie-Estelle; Mizielinski, Matthew S.; Roberts, Malcolm J.; Strachan, Jane; Vidale, Pier Luigi

    2016-04-01

    Flood events affecting large European river basins, with a drainage area on the order of 100 000 square kilometres, are largely caused by extreme precipitation over these river basins immediately preceding the river floods and lasting for one or several days. In this study, we evaluate the representation of such extreme precipitation events in the Met Office Unified Model (MetUM). Extreme-value distributions of basin-scale precipitation are estimated for high-resolution (down to about 25 km grid spacing) global MetUM simulations conducted in the project UPSCALE (UK on PRACE: weather- resolving Simulations of Climate for globAL Environmental risk), and for gridded gauge-based reference precipitation from the European Climate Assessment & Dataset (ECA&D) E-OBS product. Particular emphasis will be placed on how the representation of these extreme events depends on the horizontal grid resolution of the global atmospheric UPSCALE simulations.

  10. Physiological responses of Police Officers during job simulations wearing chemical, biological, radiological and nuclear personal protective equipment.

    PubMed

    Blacker, Sam D; Carter, James M; Wilkinson, David M; Richmond, Victoria L; Rayson, Mark P; Peattie, Malcolm

    2013-01-01

    The aim of this study was to quantify the physiological responses of Police Officers wearing chemical, biological, radiological and nuclear personal protective equipment (CBRN PPE) during firearms house entry (FE) unarmed house entry (UE) and crowd control (CC) simulations. Participants volunteered from the UK Police Force [FE (n = 6, age 33 ± 4 years, body mass 85.3 ± 7.9 kg, (·)VO₂max 53 ± 5 ml · kg⁻¹ · min⁻¹), UE and CC (n = 11, age 34 ± 5 years, body mass 88.5 ± 13.8 kg, (·)VO₂max 51 ± 5 ml · kg⁻¹ · min⁻¹)]. Heart rate reserve (HRR) during FE was greater than UE (74 ± 7 vs. 62 ± 6%HRR, p = 0.01) but lower in CC (39 ± 7%HRR, p < 0.01). Peak core body temperature was greater during FE (39.2 ± 0.3°C) than UE (38.9 ± 0.4°C, p < 0.01) and CC (37.5 ± 0.3°C, p < 0.01), with similar trends in skin temperature. There were no differences in the volume of water consumed (1.13 ± 0.44 l, p = 0.51) or change in body mass (-1.68 ± 0.65 kg, p = 0.74) between simulations. The increase in body temperature was a primary physiological limitation to performance. Cooling strategies and revised operating procedures may improve Police Officers' physical performance while wearing CBRN PPE. In recent years, the likelihood of Police Officers having to respond to a chemical, biological, nuclear or radiological (CBRN) incident wearing personal protective equipment (PPE) has increased. Such apparel is likely to increase physiological strain and impair job performance; understanding these limitations may help improve Officer safety and operational effectiveness.

  11. High-fidelity hybrid simulation of allergic emergencies demonstrates improved preparedness for office emergencies in pediatric allergy clinics.

    PubMed

    Kennedy, Joshua L; Jones, Stacie M; Porter, Nicholas; White, Marjorie L; Gephardt, Grace; Hill, Travis; Cantrell, Mary; Nick, Todd G; Melguizo, Maria; Smith, Chris; Boateng, Beatrice A; Perry, Tamara T; Scurlock, Amy M; Thompson, Tonya M

    2013-01-01

    Simulation models that used high-fidelity mannequins have shown promise in medical education, particularly for cases in which the event is uncommon. Allergy physicians encounter emergencies in their offices, and these can be the source of much trepidation. To determine if case-based simulations with high-fidelity mannequins are effective in teaching and retention of emergency management team skills. Allergy clinics were invited to Arkansas Children's Hospital Pediatric Understanding and Learning through Simulation Education center for a 1-day workshop to evaluate skills concerning the management of allergic emergencies. A Clinical Emergency Preparedness Team Performance Evaluation was developed to evaluate the competence of teams in several areas: leadership and/or role clarity, closed-loop communication, team support, situational awareness, and scenario-specific skills. Four cases, which focus on common allergic emergencies, were simulated by using high-fidelity mannequins and standardized patients. Teams were evaluated by multiple reviewers by using video recording and standardized scoring. Ten to 12 months after initial training, an unannounced in situ case was performed to determine retention of the skills training. Clinics showed significant improvements for role clarity, teamwork, situational awareness, and scenario-specific skills during the 1-day workshop (all P < .003). Follow-up in situ scenarios 10-12 months later demonstrated retention of skills training at both clinics (all P ≤ .004). Clinical Emergency Preparedness Team Performance Evaluation scores demonstrated improved team management skills with simulation training in office emergencies. Significant recall of team emergency management skills was demonstrated months after the initial training. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  12. [Simulator sickness and its measurement with Simulator Sickness Questionnaire (SSQ)].

    PubMed

    Biernacki, Marcin P; Kennedy, Robert S; Dziuda, Łukasz

    One of the most common methods for studying the simulator sickness issue is the Simulator Sickness Questionnaire (SSQ) (Kennedy et al., 1993). Despite the undoubted popularity of the SSQ, this questionnaire has not as yet been standardized and translated, which could allow us to use it in Poland for research purposes. The aim of our article is to introduce the SSQ to Polish readers, both researchers and practitioners. In the first part of this paper, the studies using the SSQ are discussed, whereas the second part consists of the description of the SSQ test procedure and the calculation method of sample results. Med Pr 2016;67(4):545-555. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  13. Risk Associated with Pulse Pressure on Out-of-Office Blood Pressure Measurement

    PubMed Central

    Gu, Yu-Mei; Aparicio, Lucas S.; Liu, Yan-Ping; Asayama, Kei; Hansen, Tine W.; Niiranen, Teemu J.; Boggia, José; Thijs, Lutgarde; Staessen, Jan A.

    2014-01-01

    Background Longitudinal studies have demonstrated that the risk of cardiovascular disease increases with pulse pressure (PP). However, PP remains an elusive cardiovascular risk factor with findings being inconsistent between studies. The 2013 ESH/ESC guideline proposed that PP is useful in stratification and suggested a threshold of 60 mm Hg, which is 10 mm Hg higher compared to that in the 2007 guideline; however, no justification for this increase was provided. Methodology Published thresholds of PP are based on office blood pressure measurement and often on arbitrary categorical analyses. In the International Database on Ambulatory blood pressure in relation to Cardiovascular Outcomes (IDACO) and the International Database on HOme blood pressure in relation to Cardiovascular Outcome (IDHOCO), we determined outcome-driven thresholds for PP based on ambulatory or home blood pressure measurement, respectively. Results The main findings were that for people aged <60 years, PP did not refine risk stratification, whereas in older people the thresholds were 64 and 76 mm Hg for the ambulatory and home PP, respectively. However, PP provided little added predictive value over and beyond classical risk factors. PMID:26587443

  14. Towards an automatic early stress recognition system for office environments based on multimodal measurements: A review.

    PubMed

    Alberdi, Ane; Aztiria, Asier; Basarab, Adrian

    2016-02-01

    Stress is a major problem of our society, as it is the cause of many health problems and huge economic losses in companies. Continuous high mental workloads and non-stop technological development, which leads to constant change and need for adaptation, makes the problem increasingly serious for office workers. To prevent stress from becoming chronic and provoking irreversible damages, it is necessary to detect it in its early stages. Unfortunately, an automatic, continuous and unobtrusive early stress detection method does not exist yet. The multimodal nature of stress and the research conducted in this area suggest that the developed method will depend on several modalities. Thus, this work reviews and brings together the recent works carried out in the automatic stress detection looking over the measurements executed along the three main modalities, namely, psychological, physiological and behavioural modalities, along with contextual measurements, in order to give hints about the most appropriate techniques to be used and thereby, to facilitate the development of such a holistic system.

  15. Variations in the Lester Hill Office Simulation at the Darmstadt Career Center.

    ERIC Educational Resources Information Center

    Douglas, Willard B.; Carter, Thomas C., III

    1979-01-01

    Describes Lester Hill, a simulated corporation, that students utilize in education for clerical, secretarial, or distributive services. Following job interviews, students, assigned to appropriate jobs, process computer cards (simulated merchandise) through sales, warehouse, traffic, and accounting departments. Reviews roles of management, outside…

  16. Simulating a Senate Office: The Impact on Student Knowledge and Attitudes

    ERIC Educational Resources Information Center

    Lay, J. Celeste; Smarick, Kathleen J.

    2006-01-01

    Although many instructors are now using simulations and other experiential pedagogies in their classrooms, the effectiveness of such tools has generally not been examined in a systematic way. In this paper, we assess the effectiveness of a simulation of the legislative process in the U.S. Senate as a tool for teaching college students about the…

  17. Simulating a Senate Office: The Impact on Student Knowledge and Attitudes

    ERIC Educational Resources Information Center

    Lay, J. Celeste; Smarick, Kathleen J.

    2006-01-01

    Although many instructors are now using simulations and other experiential pedagogies in their classrooms, the effectiveness of such tools has generally not been examined in a systematic way. In this paper, we assess the effectiveness of a simulation of the legislative process in the U.S. Senate as a tool for teaching college students about the…

  18. Associations of Objectively Measured and Self-Reported Sleep Duration With Carotid Artery Intima Media Thickness Among Police Officers

    PubMed Central

    Ma, Claudia C.; Burchfiel, Cecil M.; Charles, Luenda E.; Dorn, Joan M.; Andrew, Michael E.; Gu, Ja Kook; Joseph, Parveen Nedra; Fekedulegn, Desta; Slaven, James E.; Hartley, Tara A.; Mnatsakanova, Anna; Violanti, John M.

    2015-01-01

    Background We aimed to examine the association of objectively measured and self-reported sleep duration with carotid artery intima media thickness (IMT) among 257 police officers, a group at high risk for cardiovascular disease (CVD). Methods Sleep duration was estimated using actigraphic data and through self-reports. The mean maximum IMT was the average of the largest 12 values scanned bilaterally from three angles of the near and far wall of the common carotid, bulb, and internal carotid artery. Linear and quadratic regression models were used to assess the association of sleep duration with IMT. Results Officers who had fewer than 5 or 8 hr or more of objectively measured sleep duration had significantly higher maximum IMT values, independent of age. Self-reported sleep duration was not associated with either IMT measure. Conclusion Attainment of sufficient sleep duration may be considered as a possible strategy for atherosclerosis prevention among police officers. PMID:24038303

  19. A Simulation Method Measuring Psychomotor Nursing Skills.

    ERIC Educational Resources Information Center

    McBride, Helena; And Others

    1981-01-01

    The development of a simulation technique to evaluate performance of psychomotor skills in an undergraduate nursing program is described. This method is used as one admission requirement to an alternate route nursing program. With modifications, any health profession could use this technique where psychomotor skills performance is important.…

  20. Simple Numerical Simulation of Strain Measurement

    NASA Technical Reports Server (NTRS)

    Tai, H.

    2002-01-01

    By adopting the basic principle of the reflection (and transmission) of a plane polarized electromagnetic wave incident normal to a stack of films of alternating refractive index, a simple numerical code was written to simulate the maximum reflectivity (transmittivity) of a fiber optic Bragg grating corresponding to various non-uniform strain conditions including photo-elastic effect in certain cases.

  1. Simulation of error in optical radar range measurements.

    PubMed

    Der, S; Redman, B; Chellappa, R

    1997-09-20

    We describe a computer simulation of atmospheric and target effects on the accuracy of range measurements using pulsed laser radars with p-i-n or avalanche photodiodes for direct detection. The computer simulation produces simulated images as a function of a wide variety of atmospheric, target, and sensor parameters for laser radars with range accuracies smaller than the pulse width. The simulation allows arbitrary target geometries and simulates speckle, turbulence, and near-field and far-field effects. We compare simulation results with actual range error data collected in field tests.

  2. Evaluating the Met Office Unified Model simulated land surface temperature (LST) in northwest India

    NASA Astrophysics Data System (ADS)

    Brooke, Jennifer; Harlow, Chawn; Webster, Stuart; Gallego-Elvira, Belen

    2017-04-01

    Surface temperature biases in northwest India in the Met Office Unified Model (UM) show significant heterogeneity with distinct regions of warm and cold biases. This work will show verification of model biases through ground-based, in-situ airborne and satellite observations during the Interaction of Convective Organisation and Monsoon Precipitation, Atmosphere, Surface and Sea (INCOMPASS) campaign in northern India between May - July 2016. The INCOMPASS project is part of the "Drivers of Variability" which is a programme funded jointly by Natural Environment Research Council (NERC), the Newton fund, Indian Ministry of Earth Sciences (MoES) National Monsoon Mission, and the Met Office. MODIS climatological data and near-real time retrievals have been used to investigate the spatial biases in LST and how they correlate with model surface cover. The surface temperature biases (both warm and cold biases) in the INCOMPASS 4.4 km south Asia limited area domain are more dominant in June than May; the May MODIS climatology comparison showed the cold bias was most dominant between 72 and 75 oE, and in the June climatology comparison the cold bias had extended to almost 80 oE. The spatial distribution and magnitude of surface temperature biases and how they correlate with surface vegetation cover in the northwest region was investigated for a number of sub-regions. Region 1 (25 to 26 oN) was found to have the largest mean cold surface temperature bias and a strong correlation coefficients between the surface temperature biases and the IGBP vegetation fractional cover dataset with R2 of 0.81 (bare soil) and 0.72 (grasses). This is further supported by the strong positive correlation coefficients between the bare soil cover fraction and the cold surface temperature bias between the INCOMPASS 4.4km model and MODIS climatology for both May and June. It will be shown that regions with warm surface temperature bias in northwest India are not strongly correlated to surface cover

  3. Simulators for Mariner Training and Licensing: Guidelines for Deck Officer Training Systems.

    DTIC Science & Technology

    1982-12-01

    Rules of the limitation. This finding underscores the importance of the Road and Port Approach Planning skills were trained. The non-simulator elements...of tralning system effec- * Rules-of-the-Road relatld skills and Port Approach tivenes can be based on (1) design criteria which establish Planning ...may reflect a bridge team organizational problem, of planned ship maneuvers (NTSB Annual Report, which should be emphasized during training. Many of

  4. Requirements and Techniques for Developing and Measuring Simulant Materials

    NASA Technical Reports Server (NTRS)

    Rickman, Doug; Owens, Charles; Howard, Rick

    2006-01-01

    The 1989 workshop report entitled Workshop on Production and Uses of Simulated Lunar Materials and the Lunar Regolith Simulant Materials: Recommendations for Standardization, Production, and Usage, NASA Technical Publication identify and reinforced a need for a set of standards and requirements for the production and usage of the lunar simulant materials. As NASA need prepares to return to the moon, a set of requirements have been developed for simulant materials and methods to produce and measure those simulants have been defined. Addressed in the requirements document are: 1) a method for evaluating the quality of any simulant of a regolith, 2) the minimum Characteristics for simulants of lunar regolith, and 3) a method to produce lunar regolith simulants needed for NASA's exploration mission. A method to evaluate new and current simulants has also been rigorously defined through the mathematics of Figures of Merit (FoM), a concept new to simulant development. A single FoM is conceptually an algorithm defining a single characteristic of a simulant and provides a clear comparison of that characteristic for both the simulant and a reference material. Included as an intrinsic part of the algorithm is a minimum acceptable performance for the characteristic of interest. The algorithms for the FoM for Standard Lunar Regolith Simulants are also explicitly keyed to a recommended method to make lunar simulants.

  5. Usefulness of heart measures in flight simulation

    NASA Technical Reports Server (NTRS)

    Harris, Randall L., Sr.; Bonadies, Gregory A.; Comstock, J. Raymond, Jr.

    1990-01-01

    The results of three studies performed at the NASA Langley Research Center are presented to indicate the areas in which heart measures are useful for detecting differences in the workload state of subjects. Tasks that involve the arousal of the sympathetic nervous system, such as landing approaches, were excellent candidates for the use of average heart-rate and/or the increase in heart-rate during a task. The latter of these two measures was the better parameter because it removed the effects of diurnal variations in heart-rate and some of the intersubject variability. Tasks which differ in the amount of mental resources required are excellent candidates for heart-rate variability measures. Heart-rate variability measures based upon power spectral density techniques were responsive to the changing task demands of landing approach tasks, approach guidance options, and 2 versus 20 second interstimulus-intervals of a monitoring task. Heart-rate variability measures were especially sensitive to time-on-task when the task was characterized by minimal novelty, complexity, and uncertainty (i.e., heart-rate variability increases as a function of the subjects boredom).

  6. Control over the scheduling of simulated office work reduces the impact of workload on mental fatigue and task performance.

    PubMed

    Hockey, G Robert J; Earle, Fiona

    2006-03-01

    Two experiments tested the hypothesis that task-induced mental fatigue is moderated by control over work scheduling. Participants worked for 2 hr on simulated office work, with control manipulated by a yoking procedure. Matched participants were assigned to conditions of either high control (HC) or low control (LC). HC participants decided their own task scheduling, whereas LC participants had to follow these fixed schedules. For Experiment 1, fatigue was higher in LC participants who worked harder, so Experiment 2 compared control effects in high- and low-workload groups. As predicted, the impact of workload was reduced under HC conditions, for subjective fatigue, and most secondary tasks and aftereffects. The findings are interpreted within the framework of compensatory control theory.

  7. Invasively Measured Aortic Systolic Blood Pressure and Office Systolic Blood Pressure in Cardiovascular Risk Assessment: A Prospective Cohort Study.

    PubMed

    Laugesen, Esben; Knudsen, Søren T; Hansen, Klavs W; Rossen, Niklas B; Jensen, Lisette Okkels; Hansen, Michael G; Munkholm, Henrik; Thomsen, Kristian K; Søndergaard, Hanne; Bøttcher, Morten; Raungaard, Bent; Madsen, Morten; Hulman, Adam; Witte, Daniel; Bøtker, Hans Erik; Poulsen, Per L

    2016-09-01

    Aortic systolic blood pressure (BP) represents the hemodynamic cardiac and cerebral burden more directly than office systolic BP. Whether invasively measured aortic systolic BP confers additional prognostic value beyond office BP remains debated. In this study, office systolic BP and invasively measured aortic systolic BP were recorded in 21 908 patients (mean age: 63 years; 58% men; 14% with diabetes mellitus) with stable angina pectoris undergoing elective coronary angiography during January 2001 to December 2012. Multivariate Cox models were used to assess the association with incident myocardial infarction, stroke, and death. Discrimination and reclassification were assessed using Harrell's C and the Continuous Net Reclassification Index. Data were analyzed with and without stratification by diabetes mellitus status. During a median follow-up period of 3.7 years (range: 0.1-10.8 years), 422 strokes, 511 myocardial infarctions, and 1530 deaths occurred. Both office and aortic systolic BP were associated with stroke in patients with diabetes mellitus (hazard ratio per 10 mm Hg, 1.18 [95% confidence interval, 1.07-1.30] and 1.14 [95% confidence interval, 1.05-1.24], respectively) and with myocardial infarction in patients without diabetes mellitus (hazard ratio, 1.07 [95% confidence interval, 1.02-1.12] and 1.05 [95% confidence interval, 1.01-1.10], respectively). In models including both BP measurements, aortic BP lost statistical significance and aortic BP did not confer improvement in either C-statistics or net reclassification analysis. In conclusion, invasively measured aortic systolic BP does not add prognostic information about cardiovascular outcomes and all-cause mortality compared with office BP in patients with stable angina pectoris, either with or without diabetes mellitus. © 2016 American Heart Association, Inc.

  8. Chamber LIDAR measurements of aerosolized biological simulants

    NASA Astrophysics Data System (ADS)

    Brown, David M.; Thrush, Evan P.; Thomas, Michael E.; Siegrist, Karen M.; Baldwin, Kevin; Quizon, Jason; Carter, Christopher C.

    2009-05-01

    A chamber aerosol LIDAR is being developed to perform well-controlled tests of optical scattering characteristics of biological aerosols, including Bacillus atrophaeus (BG) and Bacillus thuringiensis (BT), for validation of optical scattering models. The 1.064 μm, sub-nanosecond pulse LIDAR allows sub-meter measurement resolution of particle depolarization ratio or backscattering cross-section at a 1 kHz repetition rate. Automated data acquisition provides the capability for real-time analysis or recording. Tests administered within the refereed 1 cubic meter chamber can provide high quality near-field backscatter measurements devoid of interference from entrance and exit window reflections. Initial chamber measurements of BG depolarization ratio are presented.

  9. Electron-cloud measurements and simulations for the APS

    SciTech Connect

    Furman, M.A.; Pivi, M.; Harkay, K.C.; Rosenberg, R.A.

    2001-06-26

    We compare experimental results with simulations of the electron cloud effect induced by a positron beam at the APS synchrotron light source at ANL, where the electron cloud effect has been observed and measured with dedicated probes. We find good agreement between simulations and measurements for reasonable values of certain secondary electron yield (SEY) parameters, most of which were extracted from recent bench measurements at SLAC.

  10. Radio Plasma Imager Simulations and Measurements

    NASA Technical Reports Server (NTRS)

    Green, J. L.; Benson, R. F.; Fung, S. F.; Taylor, W. W. L.; Boardsen, S. A.; Reinisch, B. W.; Haines, D. M.; Bibl, K.; Cheney, G.; Galkin, I. A.

    1999-01-01

    The Radio Plasma Imager (RPI) will be the first-of-its kind instrument designed to use radio wave sounding techniques to perform repetitive remote sensing measurements of electron number density (N(sub e)) structures and the dynamics of the magnetosphere and plasmasphere. RPI will fly on the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) mission to be launched early in the year 2000. The design of the RPI is based on recent advances in radio transmitter and receiver design and modern digital processing techniques perfected for ground-based ionospheric sounding over the last two decades. Free-space electromagnetic waves transmitted by the RPI located in the low density magnetospheric cavity will be reflected at distant plasma cutoffs. The location and characteristics of the plasma at those remote reflection points can then be derived from measurements of the echo amplitude, phase, delay time, frequency, polarization, Doppler shift, and echo direction. The 500 m tip-to-tip X and Y (spin plane) antennas and 20 m boom Z axis antenna on RPI will be used to measures echoes coming from distances of several R(sub E).

  11. A Measure of Psychological Realism on a Visual Simulator

    NASA Technical Reports Server (NTRS)

    Palmer, Everett; Petitt, John

    1977-01-01

    A FUNDAMENTAL question of simulation technology is how to determine if an aircraft simulation is creating the proper psychological space necessary to assess manned-system performance. The standard approach to this problem for visual simulators is to measure how well pilots can make approaches and landings on the simulator. Experiments of this type generally show that simulator performance is worse than actual landing performance and that there is an excessive amount of training required to reach acceptable performance. Unfortunately, in these experiments it is difficult to sort out the inadequacies of the visual subsystem from possible inadequacies in other simulator subsystems, such as the motion subsystem. This synoptic presents the results from one of a series of five experiments which attempted to provide direct measures of the psychological realism on a computer graphics night visual flight attachment. These experiments used experimental procedures and methodologies that psychologists have developed in their attempts to determine how people perceived visual space in the real world.

  12. A Measure of Psychological Realism on a Visual Simulator

    NASA Technical Reports Server (NTRS)

    Palmer, Everett; Petitt, John

    1977-01-01

    A FUNDAMENTAL question of simulation technology is how to determine if an aircraft simulation is creating the proper psychological space necessary to assess manned-system performance. The standard approach to this problem for visual simulators is to measure how well pilots can make approaches and landings on the simulator. Experiments of this type generally show that simulator performance is worse than actual landing performance and that there is an excessive amount of training required to reach acceptable performance. Unfortunately, in these experiments it is difficult to sort out the inadequacies of the visual subsystem from possible inadequacies in other simulator subsystems, such as the motion subsystem. This synoptic presents the results from one of a series of five experiments which attempted to provide direct measures of the psychological realism on a computer graphics night visual flight attachment. These experiments used experimental procedures and methodologies that psychologists have developed in their attempts to determine how people perceived visual space in the real world.

  13. Measured energy performance of a US-China demonstrationenergy-efficient office building

    SciTech Connect

    Xu, Peng; Huang, Joe; Jin, Ruidong; Yang, Guoxiong

    2006-08-28

    In July 1998, the U.S. Department of Energy (USDOE) and China's Ministry of Science of Technology (MOST) signed a Statement of Work (SOW) to collaborate on the design and construction of an energy-efficient demonstration office building and design center to be located in Beijing. The proposed 13,000 m{sup 2} (140,000 ft{sup 2}) nine-story office building would use U.S. energy-efficient materials, space-conditioning systems, controls, and design principles that were judged to be widely replicable throughout China. The SOW stated that China would contribute the land and provide for the costs of the base building, while the U.S. would be responsible for the additional (or marginal) costs associated with the package of energy efficiency and renewable energy improvements to the building. The project was finished and the building occupied in 2004. Using DOE-2 to analyze the energy performance of the as-built building, the building obtained 44 out of 69 possible points according to the Leadership in Energy and Environmental Design (LEED) rating, including the full maximum of 10 points in the energy performance section. The building achieved a LEED Gold rating, the first such LEED-rated office building in China, and is 60% more efficient than ASHRAE 90.1-1999. The utility data from the first year's operation match well the analysis results, providing that adjustments are made for unexpected changes in occupancy and operations. Compared with similarly equipped office buildings in Beijing, this demonstration building uses 60% less energy per floor area. However, compared to conventional office buildings with less equipment and window air-conditioners, the building uses slightly more energy per floor area.

  14. Measuring Virtual Simulations Value in Training Exercises - USMC Use Case

    DTIC Science & Technology

    2015-12-04

    Interservice/Industry Training, Simulation, and Education Conference (I/ITSEC) 2015 2015 Paper No. 15114 Page 1 of 12 Measuring Virtual ...interoperable and ‘stove-piped’ virtual and constructive Training Aids, Devices, Simulators and Simulations (TADSS) at I MEF’s First Marine...Expeditionary Brigade’s (1st MEB’s) Large Scale Exercise 2014 (LSE-14) to demonstrate that Live, Virtual , Constructive (LVC) TADSS could collectively

  15. INTERVAL SAMPLING METHODS AND MEASUREMENT ERROR: A COMPUTER SIMULATION

    PubMed Central

    Wirth, Oliver; Slaven, James; Taylor, Matthew A.

    2015-01-01

    A simulation study was conducted to provide a more thorough account of measurement error associated with interval sampling methods. A computer program simulated the application of momentary time sampling, partial-interval recording, and whole-interval recording methods on target events randomly distributed across an observation period. The simulation yielded measures of error for multiple combinations of observation period, interval duration, event duration, and cumulative event duration. The simulations were conducted up to 100 times to yield measures of error variability. Although the present simulation confirmed some previously reported characteristics of interval sampling methods, it also revealed many new findings that pertain to each method’s inherent strengths and weaknesses. The analysis and resulting error tables can help guide the selection of the most appropriate sampling method for observation-based behavioral assessments. PMID:24127380

  16. Interval sampling methods and measurement error: a computer simulation.

    PubMed

    Wirth, Oliver; Slaven, James; Taylor, Matthew A

    2014-01-01

    A simulation study was conducted to provide a more thorough account of measurement error associated with interval sampling methods. A computer program simulated the application of momentary time sampling, partial-interval recording, and whole-interval recording methods on target events randomly distributed across an observation period. The simulation yielded measures of error for multiple combinations of observation period, interval duration, event duration, and cumulative event duration. The simulations were conducted up to 100 times to yield measures of error variability. Although the present simulation confirmed some previously reported characteristics of interval sampling methods, it also revealed many new findings that pertain to each method's inherent strengths and weaknesses. The analysis and resulting error tables can help guide the selection of the most appropriate sampling method for observation-based behavioral assessments. © Society for the Experimental Analysis of Behavior.

  17. Whole body measurement systems. [for weightlessness simulation

    NASA Technical Reports Server (NTRS)

    Ogle, J. S. (Inventor)

    1973-01-01

    A system for measuring the volume and volume variations of a human body under zero gravity conditions is disclosed. An enclosed chamber having a defined volume and arranged for receiving a human body is provided with means for infrasonically varying the volume of the chamber. The changes in volume produce resultant changes in pressure, and under substantially isentropic conditions, an isentropic relationship permits a determination of gas volume which, in turn, when related to total chamber volume permits a determination of the body volume. By comparison techniques, volume changes of a human independent of gravity conditions can be determined.

  18. Relationship of off-ice and on-ice performance measures in high school male hockey players.

    PubMed

    Krause, David A; Smith, Aynsley M; Holmes, Laura C; Klebe, Corrine R; Lee, Jennifer B; Lundquist, Kimberly M; Eischen, Joseph J; Hollman, John H

    2012-05-01

    The purpose of this study was to examine the relationship of off-ice performance measures with on-ice turning, crossover, and forward skating performance in high school male hockey players. Thirty-eight players aged 15-18 (mean age ± SD: 16.4 ± 1.1 years; height: 177.9 ± 6.8 cm; weight: 72.5 ± 8.9 kg) participated in this study. On-ice tests included a forward sprint, short radius turns, and crossover turns. Off-ice tests included a 40-yd sprint, vertical jumps, horizontal jumps, and a dynamic balance test using a Y balance testing device. Five off-ice variables correlated with all on-ice performance measures. These variables included the 40-yd sprint, lateral bound right to left limb, double limb horizontal hop, balance on right in posterolateral direction, and composite balance performance on the right. Hierachical regression demonstrated that off-ice sprint time was most predictive of on-ice skating performance, accounting for 65.4% of the variability in forward skate time, 45.0% of the variability in left short radius time, 21.8% of the variance in right short radius time, 36.2% of the variance in left crossover time, and 30.8% of the variability in right crossover time. When using off-ice tests to evaluate hockey players, the 40-yd sprint is the best predictor of skating performance. Based on our regression equation, for every 1-second difference in the 40-yd sprint time, there will be approximately a 0.6-second difference in the 34.5-m on-ice sprint. The 40-yd sprint predicts forward skating performance and to a lesser degree; it also predicts crossover and tuning performance.

  19. Measurement and Simulation Results of Ti Coated Microwave Absorber

    SciTech Connect

    Sun, Ding; McGinnis, Dave; /Fermilab

    1998-11-01

    When microwave absorbers are put in a waveguide, a layer of resistive coating can change the distribution of the E-M fields and affect the attenuation of the signal within the microwave absorbers. In order to study such effect, microwave absorbers (TT2-111) were coated with titanium thin film. This report is a document on the coating process and measurement results. The measurement results have been used to check the simulation results from commercial software HFSS (High Frequency Structure Simulator.)

  20. Experimental Validation of Simulations Using Full-field Measurement Techniques

    SciTech Connect

    Hack, Erwin

    2010-05-28

    The calibration by reference materials of dynamic full-field measurement systems is discussed together with their use to validate numerical simulations of structural mechanics. The discussion addresses three challenges that are faced in these processes, i.e. how to calibrate a measuring instrument that (i) provides full-field data, and (ii) is dynamic; (iii) how to compare data from simulation and experimentation.

  1. Efficient Measurement of Multiparticle Entanglement with Embedding Quantum Simulator.

    PubMed

    Chen, Ming-Cheng; Wu, Dian; Su, Zu-En; Cai, Xin-Dong; Wang, Xi-Lin; Yang, Tao; Li, Li; Liu, Nai-Le; Lu, Chao-Yang; Pan, Jian-Wei

    2016-02-19

    The quantum measurement of entanglement is a demanding task in the field of quantum information. Here, we report the direct and scalable measurement of multiparticle entanglement with embedding photonic quantum simulators. In this embedding framework [R. Di Candia et al. Phys. Rev. Lett. 111, 240502 (2013)], the N-qubit entanglement, which does not associate with a physical observable directly, can be efficiently measured with only two (for even N) and six (for odd N) local measurement settings. Our experiment uses multiphoton quantum simulators to mimic dynamical concurrence and three-tangle entangled systems and to track their entanglement evolutions.

  2. Associations between overweight, obesity, health measures and need for recovery in office employees: a cross-sectional analysis.

    PubMed

    van der Starre, Robine E; Coffeng, Jennifer K; Hendriksen, Ingrid J M; van Mechelen, Willem; Boot, Cécile R L

    2013-12-20

    With both a high need for recovery (NFR) and overweight and obesity being a potential burden for organizations (e.g. productivity loss and sickness absence), the aim of this paper was to examine the associations between overweight and obesity and several other health measures and NFR in office workers. Baseline data of 412 office employees participating in a randomised controlled trial aimed at improving NFR in office workers were used. Associations between self-reported BMI categories (normal body weight, overweight, obesity) and several other health measures (general health, mental health, sleep quality, stress and vitality) with NFR were examined. Unadjusted and adjusted linear regression analyses were performed and adjusted for age, education and job demands. In addition, we adjusted for general health in the association between overweight and obesity and NFR. A significant positive association was observed between stress and NFR (B= 18.04, 95%CI:14.53-21.56). General health, mental health, sleep quality and vitality were negatively associated with NFR (p<0.001). Analyses also showed a significant positive association between obesity and NFR (B=8.77, 95%CI:0.01-17.56), but not between overweight and NFR. The findings suggest that self-reported stress is, and obesity may be, associated with a higher NFR. Additionally, the results imply that health measures that indicate a better health are associated with a lower NFR. The trial is registered at the Dutch Trial Register (NTR) under trial registration number: NTR2553.

  3. Relating Standardized Visual Perception Measures to Simulator Visual System Performance

    NASA Technical Reports Server (NTRS)

    Kaiser, Mary K.; Sweet, Barbara T.

    2013-01-01

    Human vision is quantified through the use of standardized clinical vision measurements. These measurements typically include visual acuity (near and far), contrast sensitivity, color vision, stereopsis (a.k.a. stereo acuity), and visual field periphery. Simulator visual system performance is specified in terms such as brightness, contrast, color depth, color gamut, gamma, resolution, and field-of-view. How do these simulator performance characteristics relate to the perceptual experience of the pilot in the simulator? In this paper, visual acuity and contrast sensitivity will be related to simulator visual system resolution, contrast, and dynamic range; similarly, color vision will be related to color depth/color gamut. Finally, we will consider how some characteristics of human vision not typically included in current clinical assessments could be used to better inform simulator requirements (e.g., relating dynamic characteristics of human vision to update rate and other temporal display characteristics).

  4. Objective measures of situation awareness in a simulated medical environment

    PubMed Central

    Wright, M; Taekman, J; Endsley, M

    2004-01-01

    One major limitation in the use of human patient simulators is a lack of objective, validated measures of human performance. Objective measures are necessary if simulators are to be used to evaluate the skills and training of medical practitioners and teams or to evaluate the impact of new processes or equipment design on overall system performance. Situation awareness (SA) refers to a person's perception and understanding of their dynamic environment. This awareness and comprehension is critical in making correct decisions that ultimately lead to correct actions in medical care settings. An objective measure of SA may be more sensitive and diagnostic than traditional performance measures. This paper reviews a theory of SA and discusses the methods required for developing an objective measure of SA within the context of a simulated medical environment. Analysis and interpretation of SA data for both individual and team performance in health care are also presented. PMID:15465958

  5. Thresholds for Diagnosing Hypertension Based on Automated Office Blood Pressure Measurements and Cardiovascular Risk.

    PubMed

    Myers, Martin G; Kaczorowski, Janusz; Paterson, J Michael; Dolovich, Lisa; Tu, Karen

    2015-09-01

    The risk of cardiovascular events in relation to blood pressure is largely based on readings taken with a mercury sphygmomanometer in populations which differ from those of today in terms of hypertension severity and drug therapy. Given replacement of the mercury sphygmomanometer with electronic devices, we sought to determine the blood pressure threshold for a significant increase in cardiovascular risk using a fully automated device, which takes multiple readings with the subject resting quietly alone. Participants were 3627 community-dwelling residents aged >65 years untreated for hypertension. Automated office blood pressure readings were obtained in a community pharmacy with subjects seated and undisturbed. This method for recording blood pressure produces similar readings in different settings, including a pharmacy and family doctor's office providing the above procedures are followed. Subjects were followed for a mean (SD) of 4.9 (1.0) years for fatal and nonfatal cardiovascular events. Adjusted hazard ratios (95% confidence intervals) were computed for 10 mm Hg increments in blood pressure (mm Hg) using Cox proportional hazards regression and the blood pressure category with the lowest event rate as the reference category. A total of 271 subjects experienced a cardiovascular event. There was a significant (P=0.02) increase in the hazard ratio of 1.66 (1.09, 2.54) at a systolic blood pressure of 135 to 144 and 1.72 (1.21, 2.45; P=0.003) at a diastolic blood pressure of 80 to 89. A significant (P=0.03) increase in hazard ratio of 1.73 (1.04, 2.86) occurred with a pulse pressure of 80 to 89. These findings are consistent with a threshold of 135/85 for diagnosing hypertension in older subjects using automated office blood pressure. © 2015 American Heart Association, Inc.

  6. Comsol Simulations as a Tool in Validating a Measurement Chamber

    NASA Astrophysics Data System (ADS)

    Lakka, Antti; Sairanen, Hannu; Heinonen, Martti; Högström, Richard

    2015-12-01

    The Centre for Metrology and Accreditation (MIKES) is developing a temperature-humidity calibration system for radiosondes. The target minimum air temperature and dew-point temperature are -80° C and -90° C, respectively. When operating in this range, a major limiting factor is the time of stabilization which is mainly affected by the design of the measurement chamber. To find an optimal geometry for the chamber, we developed a numerical simulation method taking into account heat and mass transfer in the chamber. This paper describes the method and its experimental validation using two stainless steel chambers with different geometries. The numerical simulation was carried out using Comsol Multiphysics simulation software. Equilibrium states of dry air flow at -70° C with different inlet air flow rates were used to determine the geometry of the chamber. It was revealed that the flow is very unstable despite having relatively small Reynolds number values. Humidity saturation abilities of the new chamber were studied by simulating water vapor diffusion in the chamber in time-dependent mode. The differences in time of humidity stabilization after a step change were determined for both the new chamber model and the MIKES Relative Humidity Generator III (MRHG) model. These simulations were used as a validation of the simulation method along with experimental measurements using a spectroscopic hygrometer. Humidity saturation stabilization simulations proved the new chamber to be the faster of the two, which was confirmed by experimental measurements.

  7. Measuring Surgical Skills in Simulation-based Training.

    PubMed

    Atesok, Kivanc; Satava, Richard M; Marsh, J Lawrence; Hurwitz, Shepard R

    2017-10-01

    Simulation-based surgical skills training addresses several concerns associated with the traditional apprenticeship model, including patient safety, efficient acquisition of complex skills, and cost. The surgical specialties already recognize the advantages of surgical training using simulation, and simulation-based methods are appearing in surgical education and assessment for board certification. The necessity of simulation-based methods in surgical education along with valid, objective, standardized techniques for measuring learned skills using simulators has become apparent. The most commonly used surgical skill measurement techniques in simulation-based training include questionnaires and post-training surveys, objective structured assessment of technical skills and global rating scale of performance scoring systems, structured assessments using video recording, and motion tracking software. The literature shows that the application of many of these techniques varies based on investigator preference and the convenience of the technique. As simulators become more accepted as a teaching tool, techniques to measure skill proficiencies will need to be standardized nationally and internationally.

  8. Prototype simulates remote sensing spectral measurements on fruits and vegetables

    NASA Astrophysics Data System (ADS)

    Hahn, Federico

    1998-09-01

    A prototype was designed to simulate spectral packinghouse measurements in order to simplify fruit and vegetable damage assessment. A computerized spectrometer is used together with lenses and an externally controlled illumination in order to have a remote sensing simulator. A laser is introduced between the spectrometer and the lenses in order to mark the zone where the measurement is being taken. This facilitates further correlation work and can assure that the physical and remote sensing measurements are taken in the same place. Tomato ripening and mango anthracnose spectral signatures are shown.

  9. Simulation and measurement of the resonant Schottky pickup

    NASA Astrophysics Data System (ADS)

    Zang, Yong-Dong; Wu, Jun-Xia; Zhao, Tie-Cheng; Zhang, Sheng-Hu; Mao, Rui-Shi; Xu, Hu-Shan; Sun, Zhi-Yu; Ma, Xin-Wen; Tu, Xiao-Lin; Xiao, Guo-Qing; Nolden, F.; Hülsmann, P.; Yu., A. Litvinov; Peschke, C.; Petri, P.; S. Sanjari, M.; Steck, M.

    2011-12-01

    A resonant Schottky pickup with high sensitivity, built by GSI, will be used for nuclear mass and lifetime measurement at CSRe. The basic concepts of Schottky noise signals, a brief introduction of the geometry of the detector, the transient response of the detector, and MAFIA simulated and perturbation measured results of characteristics are presented in this paper. The resonant frequency of the pickup is about 243 MHz and can be slightly changed at a range of 3 MHz. The unloaded quality factor is about 1072 and the shunt impedance is 76 kΩ. The measured results of the characteristics are in agreement with the MAFIA simulations.

  10. How Does Definition of Minimum Break Length Affect Objective Measures of Sitting Outcomes Among Office Workers?

    PubMed

    Kloster, Stine; Danquah, Ida Høgstedt; Holtermann, Andreas; Aadahl, Mette; Tolstrup, Janne Schurmann

    2017-01-01

    Harmful health effects associated with sedentary behavior may be attenuated by breaking up long periods of sitting by standing or walking. However, studies assess interruptions in sitting time differently, making comparisons between studies difficult. It has not previously been described how the definition of minimum break duration affects sitting outcomes. Therefore, the aim was to address how definitions of break length affect total sitting time, number of sit-to-stand transitions, prolonged sitting periods and time accumulated in prolonged sitting periods among office workers. Data were collected from 317 office workers. Thigh position was assessed with an ActiGraph GT3X+ fixed on the right thigh. Data were exported with varying bout length of breaks. Afterward, sitting outcomes were calculated for the respective break lengths. Absolute numbers of sit-to-stand transitions decreased, and number of prolonged sitting periods and total time accumulated in prolonged sitting periods increased, with increasing minimum break length. Total sitting time was not influenced by varying break length. The definition of minimum break length influenced the sitting outcomes with the exception of total sitting time. A standard definition of break length is needed for comparison and interpretation of studies in the evolving research field of sedentary behavior.

  11. Methodology of modeling and measuring computer architectures for plasma simulations

    NASA Technical Reports Server (NTRS)

    Wang, L. P. T.

    1977-01-01

    A brief introduction to plasma simulation using computers and the difficulties on currently available computers is given. Through the use of an analyzing and measuring methodology - SARA, the control flow and data flow of a particle simulation model REM2-1/2D are exemplified. After recursive refinements the total execution time may be greatly shortened and a fully parallel data flow can be obtained. From this data flow, a matched computer architecture or organization could be configured to achieve the computation bound of an application problem. A sequential type simulation model, an array/pipeline type simulation model, and a fully parallel simulation model of a code REM2-1/2D are proposed and analyzed. This methodology can be applied to other application problems which have implicitly parallel nature.

  12. Methodology of modeling and measuring computer architectures for plasma simulations

    NASA Technical Reports Server (NTRS)

    Wang, L. P. T.

    1977-01-01

    A brief introduction to plasma simulation using computers and the difficulties on currently available computers is given. Through the use of an analyzing and measuring methodology - SARA, the control flow and data flow of a particle simulation model REM2-1/2D are exemplified. After recursive refinements the total execution time may be greatly shortened and a fully parallel data flow can be obtained. From this data flow, a matched computer architecture or organization could be configured to achieve the computation bound of an application problem. A sequential type simulation model, an array/pipeline type simulation model, and a fully parallel simulation model of a code REM2-1/2D are proposed and analyzed. This methodology can be applied to other application problems which have implicitly parallel nature.

  13. Dual-medium quantitative measurement simulation on cells.

    PubMed

    Wang, Yawei; Jin, Weifeng; Ren, Naifei

    2011-12-10

    For research on inhomogeneous cells, we present a simulation method called the dual-medium quantitative (DMQ) measurement simulation method, which is realized by combining phase-shifting digital holography with DMQ analysis. The reliability of this method is confirmed by comparing the simulated phase map with the experimental one by the Hilbert phase microscope [J. Phys. Chem. A 113, 13327 (2009)10.1021/jp904746r], and its ability for studying inhomogeneous cells is demonstrated with measurements of a simulated HeLa cell. The average deviation and the relative deviation of physical thickness and axially averaged refractive index are 0.0339 μm, 0.69% and 0.0013, 0.094%, respectively. This approach can provide good guidance for experimental research on inhomogeneous cells. © 2011 Optical Society of America

  14. Simulations and Measurements of Stopbands in the Fermilab Recycler

    SciTech Connect

    Ainsworth, Robert; Adamson, Philip; Hazelwood, Kyle; Kourbanis, Ioanis; Stern, Eric

    2016-06-01

    Fermilab has recently completed an upgrade to the complex with the goal of delivering 700 kW of beam power as 120 GeV protons to the NuMI target. A major part of boosting beam power is to use the Fermilab Recycler to stack protons. Simulations focusing on the betatron resonance stopbands are presented taking into account different effects such as intensity and chromaticity. Simulations are compared with measurements.

  15. Thermal effects on human performance in office environment measured by integrating task speed and accuracy.

    PubMed

    Lan, Li; Wargocki, Pawel; Lian, Zhiwei

    2014-05-01

    We have proposed a method in which the speed and accuracy can be integrated into one metric of human performance. This was achieved by designing a performance task in which the subjects receive feedback on their performance by informing them whether they have committed errors, and if did, they can only proceed when the errors are corrected. Traditionally, the tasks are presented without giving this feedback and thus the speed and accuracy are treated separately. The method was examined in a subjective experiment with thermal environment as the prototypical example. During exposure in an office, 12 subjects performed tasks under two thermal conditions (neutral & warm) repeatedly. The tasks were presented with and without feedback on errors committed, as outlined above. The results indicate that there was a greater decrease in task performance due to thermal discomfort when feedback was given, compared to the performance of tasks presented without feedback. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  16. Difference between home and office blood pressures among treated hypertensive patients from the Japan Home versus Office Blood Pressure Measurement Evaluation (J-HOME) study.

    PubMed

    Horikawa, Tsuyoshi; Obara, Taku; Ohkubo, Takayoshi; Asayama, Kei; Metoki, Hirohito; Inoue, Ryusuke; Kikuya, Masahiro; Hashimoto, Junichiro; Totsune, Kazuhito; Imai, Yutaka

    2008-06-01

    This study sought to clarify the factors associated with the magnitude of the difference between home and office blood pressures in treated hypertensive patients. Study subjects consisted of 3,308 essential hypertensive patients (mean age, 66 years; males, 44%) receiving antihypertensive treatment in primary care settings in Japan. Patients were classified into 3 groups (the home effect group, small difference group, and office effect group) according to tertiles of the magnitude of the office-home systolic blood pressure difference. Compared to the other two groups, the home effect group patients were significantly and independently older, were more often habitual drinkers, had a greater family history of cerebrovascular disease or personal history of ischemic heart disease, and were prescribed a greater number of antihypertensive drugs, non-amlodipine calcium channel blockers, and alpha-blockers as antihypertensive drugs. Compared to the other two groups, the office effect group patients were significantly and independently younger, included more females, less frequently had a family history of cerebrovascular disease or personal history of ischemic heart disease, and were less often prescribed alpha-blockers as antihypertensive drugs. The characteristics of home effect group patients and the factors negatively affecting the blood pressure difference were the same. Among treated hypertensive patients, compared to patients in the other groups, office effect group patients had a lower-risk profile, whereas home effect group patients had a higher-risk profile. These predictive factors might be useful clinically to help identify patients who may have a large difference between home and office blood pressures.

  17. Water balance measurements and simulations of maize plants on lysimeters

    NASA Astrophysics Data System (ADS)

    Heinlein, Florian; Biernath, Christian; Klein, Christian; Thieme, Christoph; Priesack, Eckart

    2016-04-01

    In Central Europe expected major aspects of climate change are a shift of precipitation events and amounts towards winter months, and the general increase of extreme weather events like heat waves or summer droughts. This will lead to strongly changing regional water availability and will have an impact on future crop growth, water use efficiency and yields. Therefore, to estimate future crop yields by growth models accurate descriptions of transpiration as part of the water balance is important. In this study, maize was grown on weighing lysimeters (sowdate: 24 April 2013). Transpiration was determined by sap flow measurement devices (ICT International Pty Ltd, Australia) using the Heat-Ratio-Method: two temperature probes, 0.5 cm above and below a heater, detect a heat pulse and its speed which allows the calculation of sap flow. Water balance simulations were executed with different applications of the model framework Expert-N. The same pedotransfer and hydraulic functions and the same modules to simulate soil water flow, soil heat and nitrogen transport, nitrification, denitrification and mineralization were used. Differences occur in the chosen potential evapotranspiration ETpot (Penman-Monteith ASCE, Penman-Monteith FAO, Haude) and plant modules (SPASS, CERES). In all simulations ETpot is separated into a soil and a plant part using the leaf are index (LAI). In a next step, these parts are reduced by soil water availability. The sum of these parts is the actual evapotranspiration ETact which is compared to the lysimeter measurements. The results were analyzed from Mid-August to Mid-September 2013. The measured sap flow rates show clear diurnal cycles except on rainy days. The SPASS model is able to simulate these diurnal cycles, overestimates the measurements on rainy days and at the beginning of the analyzed period, and underestimates transpiration on the other days. The main reason is an overestimation of potential transpiration Tpot due to too high

  18. Simulation and Measurement of Stray Light in the CLASP

    NASA Technical Reports Server (NTRS)

    Narukage, Noriyuki; Kano, Ryohei; Bando, Takamasa; Ishikawa, Ryoko; Kubo, Masahito; Tsuzuki, Toshihiro; Katsukawa, Yukio; Ishikawa, Shin-nosuke; Giono, Gabriel; Suematsu, Yoshinori; Winebarger, Amy; Kobayashi, Ken

    2015-01-01

    We are planning an international rocket experiment Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is (2015 planned) that Lyman Alpha line polarization spectroscopic observations from the sun. The purpose of this experiment, detected with high accuracy of the linear polarization of the Ly?? lines to 0.1% by using a Hanle effect is to measure the magnetic field of the chromosphere-transition layer directly. For total flux of the sun visible light overwhelmingly larger and about 200 000 times the Ly?? line wavelength region, also hinder to 0.1% of the polarization photometric accuracy achieved in the stray light of slight visible light. Therefore we were first carried out using the illumination design analysis software called stray light simulation CLASP Light Tools. Feature of this simulation, using optical design file (ZEMAX format) and structural design file (STEP format), to reproduce realistic CLASP as possible to calculate machine is that it was stray study. And, at the stage in the actual equipment that made the provisional set of CLASP, actually put sunlight into CLASP using coelostat of National Astronomical Observatory of Japan, was subjected to measurement of stray light (San test). Pattern was not observed in the simulation is observed in the stray light measurement results need arise that measures. However, thanks to the stray light measurement and simulation was performed by adding, it was found this pattern is due to the diffracted light at the slit. Currently, the simulation results is where you have taken steps to reference. In this presentation, we report the stray light simulation and stray light measurement results that we have implemented

  19. Computer simulation of fibrillation threshold measurements and electrophysiologic testing procedures

    NASA Technical Reports Server (NTRS)

    Grumbach, M. P.; Saxberg, B. E.; Cohen, R. J.

    1987-01-01

    A finite element model of cardiac conduction was used to simulate two experimental protocols: 1) fibrillation threshold measurements and 2) clinical electrophysiologic (EP) testing procedures. The model consisted of a cylindrical lattice whose properties were determined by four parameters: element length, conduction velocity, mean refractory period, and standard deviation of refractory periods. Different stimulation patterns were applied to the lattice under a given set of lattice parameter values and the response of the model was observed through a simulated electrocardiogram. The studies confirm that the model can account for observations made in experimental fibrillation threshold measurements and in clinical EP testing protocols.

  20. A computer simulation approach to measurement of human control strategy

    NASA Technical Reports Server (NTRS)

    Green, J.; Davenport, E. L.; Engler, H. F.; Sears, W. E., III

    1982-01-01

    Human control strategy is measured through use of a psychologically-based computer simulation which reflects a broader theory of control behavior. The simulation is called the human operator performance emulator, or HOPE. HOPE was designed to emulate control learning in a one-dimensional preview tracking task and to measure control strategy in that setting. When given a numerical representation of a track and information about current position in relation to that track, HOPE generates positions for a stick controlling the cursor to be moved along the track. In other words, HOPE generates control stick behavior corresponding to that which might be used by a person learning preview tracking.

  1. Measurement and simulation of the segmented Germanium-Detector's Efficiency

    NASA Astrophysics Data System (ADS)

    Salem, Shadi

    This paper presents the methods to determine the detection efficiency of the segmented germanium detector. Two methods are given for the investigating the detection efficiency of the semiconductor segmented-germanium detector. Experimental measurements using radioactive sources are reported. The radioactive sources, which were involved, can give us the opportunity to cover the photon energy ranging up to hundreds of keV. A useful compilation is included of the latest values of the emission rates per decay for the following radioactive sources: 241Am and 133Ba. The second method, the simulation of the efficiency is involved for comparison purposes. A good agreement between the measurements and the simulation is obtained.

  2. A computer simulation approach to measurement of human control strategy

    NASA Technical Reports Server (NTRS)

    Green, J.; Davenport, E. L.; Engler, H. F.; Sears, W. E., III

    1982-01-01

    Human control strategy is measured through use of a psychologically-based computer simulation which reflects a broader theory of control behavior. The simulation is called the human operator performance emulator, or HOPE. HOPE was designed to emulate control learning in a one-dimensional preview tracking task and to measure control strategy in that setting. When given a numerical representation of a track and information about current position in relation to that track, HOPE generates positions for a stick controlling the cursor to be moved along the track. In other words, HOPE generates control stick behavior corresponding to that which might be used by a person learning preview tracking.

  3. Computer simulation of fibrillation threshold measurements and electrophysiologic testing procedures

    NASA Technical Reports Server (NTRS)

    Grumbach, M. P.; Saxberg, B. E.; Cohen, R. J.

    1987-01-01

    A finite element model of cardiac conduction was used to simulate two experimental protocols: 1) fibrillation threshold measurements and 2) clinical electrophysiologic (EP) testing procedures. The model consisted of a cylindrical lattice whose properties were determined by four parameters: element length, conduction velocity, mean refractory period, and standard deviation of refractory periods. Different stimulation patterns were applied to the lattice under a given set of lattice parameter values and the response of the model was observed through a simulated electrocardiogram. The studies confirm that the model can account for observations made in experimental fibrillation threshold measurements and in clinical EP testing protocols.

  4. Associations between overweight, obesity, health measures and need for recovery in office employees: a cross-sectional analysis

    PubMed Central

    2013-01-01

    Background With both a high need for recovery (NFR) and overweight and obesity being a potential burden for organizations (e.g. productivity loss and sickness absence), the aim of this paper was to examine the associations between overweight and obesity and several other health measures and NFR in office workers. Methods Baseline data of 412 office employees participating in a randomised controlled trial aimed at improving NFR in office workers were used. Associations between self-reported BMI categories (normal body weight, overweight, obesity) and several other health measures (general health, mental health, sleep quality, stress and vitality) with NFR were examined. Unadjusted and adjusted linear regression analyses were performed and adjusted for age, education and job demands. In addition, we adjusted for general health in the association between overweight and obesity and NFR. Results A significant positive association was observed between stress and NFR (B = 18.04, 95%CI:14.53-21.56). General health, mental health, sleep quality and vitality were negatively associated with NFR (p < 0.001). Analyses also showed a significant positive association between obesity and NFR (B = 8.77, 95%CI:0.01-17.56), but not between overweight and NFR. Conclusions The findings suggest that self-reported stress is, and obesity may be, associated with a higher NFR. Additionally, the results imply that health measures that indicate a better health are associated with a lower NFR. Trial registration The trial is registered at the Dutch Trial Register (NTR) under trial registration number: NTR2553. PMID:24359267

  5. Measuring Maturity of Use for Electronic Medical Records (EMRs) in British Columbia: The Physician Information Technology Office (PITO).

    PubMed

    Rimmer, Carol; Hagens, Simon; Baldwin, Anne; Anderson, Carol J

    2014-01-01

    This article examines British Columbia (BC)'s Physician Information Technology Office's efforts to measure and improve the use of electronic medical records (EMRs) by select practices in BC with an assessment of their progress using a maturity model, and targeted support. The follow-up assessments showed substantial increases in the physicians' scores resulting from action plans that comprised a series of tailored support activities. Specifically, there was an increase from 21% to 83% of physicians who could demonstrate that they used their EMRs as the principal method of record-keeping.

  6. Generation of Requirements for Simulant Measurements. Revised, May 30, 2010

    NASA Technical Reports Server (NTRS)

    Rickman, Doug; Edmunson, Jennifer

    2010-01-01

    This document provides a formal, logical explanation of the parameters selected for the Figure of Merit algorithm used to evaluate lunar regolith simulant. The objectives, requirements, assumptions and analysis behind the parameters is provided. From NASA's objectives for lunar simulants a requirement is derived to verify and validate simulant performance versus lunar regolith. This requirement leads to a specification that comparative measurements be taken the same way on the regolith and the simulant. In turn this leads to a set of 9 criteria with which to evaluate comparative measurement. Many of the potential measurements of interest are not defensible under these criteria, for example many geotechnical properties of interest were not explicitly measured during Apollo and they can only be measured in situ on the Moon. A 2005 workshop identified 32 properties of major interest to users (Sibille Carpenter Schlagheck, and French, 2006). Virtually all of the properties are tightly constrained, though not predictable, if just four parameters are controlled. Three: composition, size and shape, are recognized as being definable at the particle level. The fourth, density, is a bulk property. In recent work a fifth parameter has been identified, which will need to be added to future releases of the Figure of Merit: spectroscopy.

  7. Temperature measurement error simulation of the pure rotational Raman lidar

    NASA Astrophysics Data System (ADS)

    Jia, Jingyu; Huang, Yong; Wang, Zhirui; Yi, Fan; Shen, Jianglin; Jia, Xiaoxing; Chen, Huabin; Yang, Chuan; Zhang, Mingyang

    2015-11-01

    Temperature represents the atmospheric thermodynamic state. Measure the atmospheric temperature accurately and precisely is very important to understand the physics of the atmospheric process. Lidar has some advantages in the atmospheric temperature measurement. Based on the lidar equation and the theory of pure rotational Raman (PRR), we've simulated the temperature measurement errors of the double-grating-polychromator (DGP) based PRR lidar. First of all, without considering the attenuation terms of the atmospheric transmittance and the range in the lidar equation, we've simulated the temperature measurement errors which are influenced by the beam splitting system parameters, such as the center wavelength, the receiving bandwidth and the atmospheric temperature. We analyzed three types of the temperature measurement errors in theory. We've proposed several design methods for the beam splitting system to reduce the temperature measurement errors. Secondly, we simulated the temperature measurement error profiles by the lidar equation. As the lidar power-aperture product is determined, the main target of our lidar system is to reduce the statistical and the leakage errors.

  8. A COMPARISON OF GADRAS SIMULATED AND MEASURED GAMMA RAY SPECTRA

    SciTech Connect

    Jeffcoat, R.; Salaymeh, S.

    2010-06-28

    Gamma-ray radiation detection systems are continuously being developed and improved for detecting the presence of radioactive material and for identifying isotopes present. Gamma-ray spectra, from many different isotopes and in different types and thicknesses of attenuation material and matrixes, are needed to evaluate the performance of these devices. Recently, a test and evaluation exercise was performed by the Savannah River National Laboratory that required a large number of gamma-ray spectra. Simulated spectra were used for a major portion of the testing in order to provide a pool of data large enough for the results to be statistically significant. The test data set was comprised of two types of data, measured and simulated. The measured data were acquired with a hand-held Radioisotope Identification Device (RIID) and simulated spectra were created using Gamma Detector Response and Analysis Software (GADRAS, Mitchell and Mattingly, Sandia National Laboratory). GADRAS uses a one-dimensional discrete ordinate calculation to simulate gamma-ray spectra. The measured and simulated spectra have been analyzed and compared. This paper will discuss the results of the comparison and offer explanations for spectral differences.

  9. Measurement of performance of solar-heated office buildings. Final report, June 1, 1982-October 31, 1983

    SciTech Connect

    Norford, L.N.; Rabl, A.; Socolow, R.H.

    1984-01-01

    Prudential Insurance Company is building two new office buildings that are a showcase of innovative energy efficient design and solar energy utilization. In order for this effort to be fully successful, the actual performance of these buildings needs to be monitored. This report summarizes the progress made during the first year. A thorough theoretical analysis has been carried out, using the DOE2.1 computer simulation code. This analysis has been supplemented by shorthand calculations and by special models to provide an independent check of the coding and to evaluate certain features, e.g. the double wall, that cannot be modeled by DOE2.1. A steady state shorthand method has been developed to calculate annual energy use; it is a modification of the ASHRAE bin method and agrees with the computer simulation within about 15% for cooling and 2% for heating. Energy savings due to daylighting have been evaluated using both shorthand methods and the computer code DOE2.1b. The calculations of annual energy use that were performed at the design stage have been reproduced, and changes during later design phases, e.g. the outdoor air flow rate, have been identified. Even without a variety of further energy savings that appear feasible, these buildings promise to be among the most efficient in the current stock of office buildings. A 100-channel instrumentation and data acquisition system has been designed, and installation should be complete by February 1984. Extensive software has been prepared to confront the model predictions with field data.

  10. Calibration of three rainfall simulators with automatic measurement methods

    NASA Astrophysics Data System (ADS)

    Roldan, Margarita

    2010-05-01

    CALIBRATION OF THREE RAINFALL SIMULATORS WITH AUTOMATIC MEASUREMENT METHODS M. Roldán (1), I. Martín (2), F. Martín (2), S. de Alba(3), M. Alcázar(3), F.I. Cermeño(3) 1 Grupo de Investigación Ecología y Gestión Forestal Sostenible. ECOGESFOR-Universidad Politécnica de Madrid. E.U.I.T. Forestal. Avda. Ramiro de Maeztu s/n. Ciudad Universitaria. 28040 Madrid. margarita.roldan@upm.es 2 E.U.I.T. Forestal. Avda. Ramiro de Maeztu s/n. Ciudad Universitaria. 28040 Madrid. 3 Facultad de Ciencias Geológicas. Universidad Complutense de Madrid. Ciudad Universitaria s/n. 28040 Madrid The rainfall erosivity is the potential ability of rain to cause erosion. It is function of the physical characteristics of rainfall (Hudson, 1971). Most expressions describing erosivity are related to kinetic energy or momentum and so with drop mass or size and fall velocity. Therefore, research on factors determining erosivity leds to the necessity to study the relation between fall height and fall velocity for different drop sizes, generated in a rainfall simulator (Epema G.F.and Riezebos H.Th, 1983) Rainfall simulators are one of the most used tools for erosion studies and are used to determine fall velocity and drop size. Rainfall simulators allow repeated and multiple measurements The main reason for use of rainfall simulation as a research tool is to reproduce in a controlled way the behaviour expected in the natural environment. But in many occasions when simulated rain is used in order to compare it with natural rain, there is a lack of correspondence between natural and simulated rain and this can introduce some doubt about validity of data because the characteristics of natural rain are not adequately represented in rainfall simulation research (Dunkerley D., 2008). Many times the rainfall simulations have high rain rates and they do not resemble natural rain events and these measures are not comparables. And besides the intensity is related to the kinetic energy which

  11. Monte Carlo simulation of portal detectors of a steel factory. Comparison of measured and simulated response

    NASA Astrophysics Data System (ADS)

    Takoudis, G.; Xanthos, S.; Clouvas, A.; Antonopoulos-Domis, M.; Potiriadis, C.

    2007-09-01

    Metal scrap is widely used in steel production. Millions of tons of scrap metal are traded each year worldwide; hence, both national and international authorities have shown an increasing interest in the probing and detection of radioactivity contamination in scrap metal. In order to minimize and/or avoid economical losses and material contamination, portal monitors have been installed at the entrance point of installations of many steel industries. Portal monitors typically consist of large organic scintillation detectors. The purpose of this study is to simulate such detectors and compare simulation results with experimental measurements in order to understand, calibrate and effectively use the detectors' response. Monte Carlo simulations of these systems demonstrate the assumptions that have to be made for optimal matching of measured and simulated results. As it was reported in previous studies, we observed a difference between measured and experimental values next to the light guide. In this work, we propose a transition area near the boundary surface of the scintillator and the light guide; this results in a good qualitative and quantitative agreement of measured and simulated results. This study will also define a guideline for later portal monitor simulations and a reliable estimation of the portals' efficiency.

  12. Absorptivity Measurements and Heat Source Modeling to Simulate Laser Cladding

    NASA Astrophysics Data System (ADS)

    Wirth, Florian; Eisenbarth, Daniel; Wegener, Konrad

    The laser cladding process gains importance, as it does not only allow the application of surface coatings, but also additive manufacturing of three-dimensional parts. In both cases, process simulation can contribute to process optimization. Heat source modeling is one of the main issues for an accurate model and simulation of the laser cladding process. While the laser beam intensity distribution is readily known, the other two main effects on the process' heat input are non-trivial. Namely the measurement of the absorptivity of the applied materials as well as the powder attenuation. Therefore, calorimetry measurements were carried out. The measurement method and the measurement results for laser cladding of Stellite 6 on structural steel S 235 and for the processing of Inconel 625 are presented both using a CO2 laser as well as a high power diode laser (HPDL). Additionally, a heat source model is deduced.

  13. Unravelling quantum dot array simulators via singlet-triplet measurements

    NASA Astrophysics Data System (ADS)

    Gray, Johnnie; Bayat, Abolfazl; Puddy, Reuben K.; Smith, Charles G.; Bose, Sougato

    2016-11-01

    Recently, singlet-triplet measurements in double dots have emerged as a powerful tool in quantum information processing. In parallel, quantum dot arrays are being envisaged as analog quantum simulators of many-body models. Thus motivated, we explore the potential of the above singlet-triplet measurements for probing and exploiting the ground state of a Heisenberg spin chain in such a quantum simulator. We formulate an efficient protocol to discriminate the achieved many-body ground state with other likely states. Moreover, the transition between quantum phases, arising from the addition of frustrations in a J1-J2 model, can be systematically explored using the same set of measurements. We show that the proposed measurements have an application in producing long distance heralded entanglement between well separated quantum dots. Relevant noise sources, such as nonzero temperatures and nuclear spin interactions, are considered.

  14. NIF-0096141-OA Prop Simulations of NEL PBRS Measurements

    SciTech Connect

    Widmayer, C; Manes, K

    2003-02-21

    Portable Back Reflection Sensor, PBRS, (NEL only) and Quad Back Reflection Sensor, QBRS, time delay reflectometer traces are among the most useful diagnostics of NIF laser status available. NEL PBRS measurements show several signals reaching the detector for each shot. The time delay between signals suggests that the largest of these is due to energy at the spatial filter pinhole planes leaking into adjacent pinholes and traveling back upstream to the PBRS. Prop simulations agree with current PBRS measurements to within 50%. This suggests that pinhole leakage is the dominant source of energy at the PBRS. However, the simulations predict that the energy leakage is proportional to beam output energy, while the PBRS measurements increase more slowly (''saturate''). Further refinement of the model or the measurement may be necessary to resolve this discrepancy.

  15. Measuring Financial Literacy: Developing and Testing a Measurement Instrument with a Selected Group of South African Military Officers

    ERIC Educational Resources Information Center

    Schwella, E.; van Nieuwenhuyzen, Bernard J.

    2014-01-01

    Are South Africans financially literate, and how can this be measured? Until 2009 there was no South African financial literacy measure and, therefore, the aim was to develop a South African measurement instrument that is scientific, socially acceptable, valid and reliable. To achieve this aim a contextual and conceptual analysis of financial…

  16. Measuring Financial Literacy: Developing and Testing a Measurement Instrument with a Selected Group of South African Military Officers

    ERIC Educational Resources Information Center

    Schwella, E.; van Nieuwenhuyzen, Bernard J.

    2014-01-01

    Are South Africans financially literate, and how can this be measured? Until 2009 there was no South African financial literacy measure and, therefore, the aim was to develop a South African measurement instrument that is scientific, socially acceptable, valid and reliable. To achieve this aim a contextual and conceptual analysis of financial…

  17. Radiological Disaster Simulators for Field and Aerial Measurements

    SciTech Connect

    H. W. Clark, Jr

    2002-11-01

    Simulators have been developed to dramatically improve the fidelity of play for field monitors and aircraft participating in radiological disaster drills and exercises. Simulated radiological measurements for the current Global Positioning System (GPS) location are derived from realistic models of radiological consequences for accidents and malicious acts. The aerial version outputs analog pulses corresponding to the signal that would be produced by various NaI (Tl) detectors at that location. The field monitor version reports the reading for any make/model of survey instrument selected. Position simulation modes are included in the aerial and field versions. The aerial version can generate a flight path based on input parameters or import an externally generated sequence of latitude and longitude coordinates. The field version utilizes a map-based point and click/drag interface to generate individual or a sequence of evenly spaced instrument measurements.

  18. Performance Measures for Evaluating Public Participation Activities in the Office of Environmental Management (DOE)

    SciTech Connect

    Carnes, S.A.

    2001-02-15

    Public participation in Office of Environmental Management (EM) activities throughout the DOE complex is a critical component of the overall success of remediation and waste management efforts. The challenges facing EM and its stakeholders over the next decade or more are daunting (Nuclear Waste News 1996). Achieving a mission composed of such challenges will require innovation, dedication, and a significant degree of good will among all stakeholders. EM's efforts to date, including obtaining and using inputs offered by EM stakeholders, have been notable. Public participation specialists have accepted and met challenges and have consistently tried to improve their performance. They have reported their experiences both formally and informally (e.g., at professional conferences and EM Public Participation Network Workshops, other internal meetings of DOE and contractor public participation specialists, and one-on-one consultations) in order to advance the state of their practice. Our research, and our field research in particular (including our interactions with many representatives of numerous stakeholder groups at nine DOE sites with diverse EM problems), have shown that it, is possible to develop coherent results even in a problem domain as complex as that of EM. We conclude that performance-based evaluations of public participation appear possible, and we have recommended an approach, based on combined and integrated multi-stakeholder views on the attributes of successful public participation and associated performance indicators, that seems workable and should be acceptable to diverse stakeholders. Of course, as an untested recommendation, our approach needs the validation that can only be achieved by application (perhaps at a few DOE sites with ongoing EM activities). Such an application would serve to refine the proposed approach in terms of its clarity, its workability, and its potential for full-scale use by EM and, potentially, other government agencies and

  19. Comparison of Experimentally Measured Rayleigh-Taylor Growth to Hydrodynamic Simulations

    NASA Astrophysics Data System (ADS)

    Knauer, J. P.; Verdon, C. P.; Betti, R.; Meyerhofer, D. D.; Boehly, T. R.; Bradley, D. K.; Smalyuk, V. A.

    1997-11-01

    Experimental measurements of perturbation growth due to the Rayleigh-Taylor (RT) instability at the ablation interface have been used to try to understand the physical processes involved in ablative stabilization. The growth rate calculated from a dispersion relation and values for the acceleration and ablation velocity determined by a numerical simulation are compared to a growth rate from an experiment where the numerical simulation includes the correct ablation interface physics. Planar targets with initial perturbations of 20-, 31-, and 60- μ*m wavelengths and initial amplitudes of 0.5 μ*m have been accelerated. The analysis shows that the growth rate determined from an x-ray radiograph of the planar foil should not be compared with the results from a dispersion formula that calculates the spatial development of the perturbation. The ORCHID* simulation indicates a significant modification to the density distribution so that the measurement of ρΔ*x* does not reflect the evolution of Δ*x*. The amplitude of a perturbation measured as ρΔ*x* can be characterized as a=a0 ^**e^γ*^t*+c*, where a_0* is the initial amplitude, γ* is the growth rate, and c is a slowly varying function of time. This work was supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement No. DE-FC03-92SF19460.

  20. A1cNow® InView™: A New Simple Method for Office-Based Glycohemoglobin Measurement

    PubMed Central

    Mattewal, Amarbir; Aldasouqi, Saleh; Solomon, David; Gossain, Ved; Koller, Anthony

    2007-01-01

    Background Glycohemoglobin A1c (HbA1c) is a universally accepted tool for glycemic control. Portable HbA1c devices for use in physicians' offices are desirable because they provide immediate results that physicians can share with their patients. This has been shown to enhance self-management in patients with diabetes. We undertook this study to evaluate the accuracy and precision of a recently introduced device, the A1cNow® InView™ capillary monitor. Methods Previously tested EDTA-preserved whole blood samples from our laboratory pool were preselected based on the results of HbA1c to cover a range from 4 to 13%. HbA1c was then measured using an A1cNow InView capillary monitor. Blinded aliquots of these samples were then sent to a National Glycohemoglobin Standardization Program (NGSP)-certified reference laboratory for comparison. One sample with a laboratory HbA1c result of 9.2% was measured with the InView device nine successive times to assess the device precision. The consistency between the measurement of HbA1c measured by the reference laboratory and the A1cNow InView device was analyzed via linear regression. Results Thirty-five samples were tested. The correlation between HbA1c measured by the InView device and the reference laboratory, as well as our own laboratory, was 0.96. The coefficient of variation was 2.71%. Conclusions Results of this study confirm the accuracy and precision of the InView capillary HbA1c monitor. However, the feasibility, reproducibility, and cost-effectiveness of this promising device in the real-life settings of physicians' offices must be verified by prospective clinical studies. PMID:19885160

  1. Report: Office of Research and Development Needs to Improve Its Method of Measuring Administrative Savings

    EPA Pesticide Factsheets

    Report #11-P-0333, July 14, 2011. ORD’s efforts to reduce its administrative costs are noteworthy, but ORD needs to improve its measurement mechanism for assessing the effectiveness of its initiatives to reduce administrative costs.

  2. Measurement and simulation of deformation and stresses in steel casting

    NASA Astrophysics Data System (ADS)

    Galles, D.; Monroe, C. A.; Beckermann, C.

    2012-07-01

    Experiments are conducted to measure displacements and forces during casting of a steel bar in a sand mold. In some experiments the bar is allowed to contract freely, while in others the bar is manually strained using embedded rods connected to a frame. Solidification and cooling of the experimental castings are simulated using a commercial code, and good agreement between measured and predicted temperatures is obtained. The deformations and stresses in the experiments are simulated using an elasto-viscoplastic finite-element model. The high temperature mechanical properties are estimated from data available in the literature. The mush is modeled using porous metal plasticity theory, where the coherency and coalescence solid fraction are taken into account. Good agreement is obtained between measured and predicted displacements and forces. The results shed considerable light on the modeling of stresses in steel casting and help in developing more accurate models for predicting hot tears and casting distortions.

  3. Simulating performance impacts of bus lanes and supporting measures

    SciTech Connect

    Shalaby, A.S.

    1999-10-01

    This study used the TRANSYT-7F simulator to examine changes in performance measures of through buses and adjacent traffic following the introduction of reserved lanes in an urban arterial. In addition, the TRANSYT-7F simulator was used to examine the specific impacts on modal performance of two policy measures implemented in conjunction with lane introduction. The results showed that TRANSYT-7F provided relatively accurate estimates of bus delays and auto speeds. However, the study identified one area of improvement for TRANSYT-7F to model priority treatments on arterials more effectively. The simulation results showed that the performance of the average bus improved after project implementation, whereas the performance of the adjacent through traffic deteriorated. However, the deterioration exceeded the improvement. Other aggregate estimates of performance were examined and discussed. The simulations also showed that modifications to left-turn movements would have a minor impact on both bus and adjacent traffic performance, whereas the removal of taxis from the reserved lanes would cause far more performance deterioration to the adjacent traffic than the performance improvement this policy measure would bring to buses.

  4. Measurement and simulation of apertures on Z hohlraums

    SciTech Connect

    Chrien, R.E.; Matuska, W. Jr.; Swenson, F.J.

    1998-12-01

    The authors have performed aperture measurements and simulations for vacuum hohlraums heated by wire array implosions. A low-Z plastic coating is often applied to the aperture to create a high ablation pressure which retards the expansion of the gold hohlraum wall. However, this interface is unstable and may be subjects to the development of highly nonlinear perturbations (jets) as a result of shocks converging near the edge of the aperture. These experiments have been simulated using Lagrangian and Eulerian radiation hydrodynamics codes.

  5. Shear Strength Measurement Benchmarking Tests for K Basin Sludge Simulants

    SciTech Connect

    Burns, Carolyn A.; Daniel, Richard C.; Enderlin, Carl W.; Luna, Maria; Schmidt, Andrew J.

    2009-06-10

    Equipment development and demonstration testing for sludge retrieval is being conducted by the K Basin Sludge Treatment Project (STP) at the MASF (Maintenance and Storage Facility) using sludge simulants. In testing performed at the Pacific Northwest National Laboratory (under contract with the CH2M Hill Plateau Remediation Company), the performance of the Geovane instrument was successfully benchmarked against the M5 Haake rheometer using a series of simulants with shear strengths (τ) ranging from about 700 to 22,000 Pa (shaft corrected). Operating steps for obtaining consistent shear strength measurements with the Geovane instrument during the benchmark testing were refined and documented.

  6. Electron Beam Lifetime in SPEAR3: Measurement and Simulation

    SciTech Connect

    Corbett, J.; Huang, X.; Lee, M.; Lui, P.; Sayyar-Rodsari, B.; /Pavilon Tech., Austin

    2007-12-19

    In this paper we report on electron beam lifetime measurements as a function of scraper position, RF voltage and bunch fill pattern in SPEAR3. We then outline development of an empirical, macroscopic model using the beam-loss rate equation. By identifying the dependence of loss coefficients on accelerator and beam parameters, a numerically-integrating simulator can be constructed to compute beam decay with time. In a companion paper, the simulator is used to train a parametric, non-linear dynamics model for the system [1].

  7. A Simulation Model for Measuring Customer Satisfaction through Employee Satisfaction

    NASA Astrophysics Data System (ADS)

    Zondiros, Dimitris; Konstantopoulos, Nikolaos; Tomaras, Petros

    2007-12-01

    Customer satisfaction is defined as a measure of how a firm's product or service performs compared to customer's expectations. It has long been a subject of research due to its importance for measuring marketing and business performance. A lot of models have been developed for its measurement. This paper propose a simulation model using employee satisfaction as one of the most important factors leading to customer satisfaction (the others being expectations and disconfirmation of expectations). Data obtained from a two-year survey in customers of banks in Greece were used. The application of three approaches regarding employee satisfaction resulted in greater customer satisfaction when there is serious effort to keep employees satisfied.

  8. Operation Dominic, Christmas series. Project Officer's report. Project 4. 2. Photoelectric and psychophysical measures of weapon flashes

    SciTech Connect

    Hill, J.H.; Chisum, G.T.; Richardson, R.A.

    1985-09-01

    The objectives of this report were (1) to obtain measures of luminous densities during the first 100 milliseconds following the detonation of nuclear weapons; (2) to obtain field verification of the flashblinding effects of weapon flashes; and (3) to establish the extent of agreement between the degree of flashblindness produced by actual events and that produced in laboratory simulations.

  9. Operation SUN BEAM. Shot Small Boy, Project Officers’ Report. Project 2. 1. Initial Radiation Measurements

    DTIC Science & Technology

    1981-05-01

    overload properties of the VCO, but some is of external origin. The source of this latter component has not been identified. (U) The traces from the...needs more attention. M) The colligated Measurement at 468 meters shows that the gamma-ray rate from the device itself fails the level expected

  10. Simulations of infrared atmospheric transmittance based on measured data

    NASA Astrophysics Data System (ADS)

    Song, Fu-yin; Lu, Yuan; Qiao, Ya; Tao, Hui-feng; Tang, Cong; Ling, Yong-shun

    2016-10-01

    There are two regular methods to calculate infrared atmospheric transmittance, including empirical formula and professional software. However, it has large deviations to use empirical formula. It is complicated to use professional software and difficult to apply in other infrared simulative system. Therefore, based on measured atmospheric data in some area for many years, article used the method of molecular single absorption to calculate absorption coefficients of water vapor and carbon dioxide in different temperature. Temperatures, pressures, and consequent scattering coefficients which distributed in different high were fitted with analysis formula according to different months. Then, it built simulative calculation model of atmospheric transmittance of infrared radiation. The simulative results are very close to accuracy results calculated by user-defined model of MODTRAN. The method is easy and convenient to use and has certain referent value in the project application.

  11. Thermal crosstalk simulation and measurement of linear terahertz detector arrays

    NASA Astrophysics Data System (ADS)

    Li, Weizhi; Huang, Zehua; Wang, Jun; Li, Mingyu; Gou, Jun; Jiang, Yadong

    2015-11-01

    Thermal simulation of differently structured linear terahertz detector arrays (TDAs) based on lithium tantalate was performed by finite element analysis (FEA). Simulation results revealed that a relatively simple TDA structure can have good thermal insulation, i.e., low thermal crosstalk effect (TCE), between adjacent pixels, which was thus selected for the real fabrication of TDA sample. Current responsivity (Ri) of the sample for a 2.52 THz source was measured to be 6.66 × 10-6 A/W and non-uniformity (NU) of Ri was 4.1%, showing good performance of the sample. TCE test result demonstrated that small TCE existed in the sample, which was in good agreement with the simulation results.

  12. PINS Measurements of Explosive Simulants for Cargo Screening

    SciTech Connect

    E.H. Seabury

    2008-06-01

    As part of its efforts to prevent the introduction of explosive threats on commercial flights, the Transportation Security Administration (TSL) is evaluating new explosives detection systems (EDSs) for use in air cargo inspection. The TSL has contracted Battelle to develop a new type of explosives simulant to assist in this development. These are designed to mimic the elemental profile (C, H, N, O, etc.) of explosives as well as their densities. Several “neutron in—gamma out” (n,?) techniques have been considered to quantify the elemental profile in these new simulants and the respective explosives. The method chosen by Battelle is Portable Isotopic Neutron Spectroscopy (PINS), developed by Idaho National Laboratory (INL). Battelle wishes to validate that the simulants behave like the explosive threats with this technology. The results of the validation measurements are presented in this report.

  13. Simulating Scintillator Light Collection Using Measured Optical Reflectance

    SciTech Connect

    Janecek, Martin; Moses, William

    2010-01-28

    To accurately predict the light collection from a scintillating crystal through Monte Carlo simulations, it is crucial to know the angular distribution from the surface reflectance. Current Monte Carlo codes allow the user to set the optical reflectance to a linear combination of backscatter spike, specular spike, specular lobe, and Lambertian reflections. However, not all light distributions can be expressed in this way. In addition, the user seldom has the detailed knowledge about the surfaces that is required for accurate modeling. We have previously measured the angular distributions within BGO crystals and now incorporate these data as look-up-tables (LUTs) into modified Geant4 and GATE Monte Carlo codes. The modified codes allow the user to specify the surface treatment (ground, etched, or polished), the attached reflector (Lumirror(R), Teflon(R), ESR film, Tyvek(R), or TiO paint), and the bonding type (air-coupled or glued). Each LUT consists of measured angular distributions with 4o by 5o resolution in theta and phi, respectively, for incidence angles from 0? to 90? degrees, in 1o-steps. We compared the new codes to the original codes by running simulations with a 3 x 10 x 30 mm3 BGO crystal coupled to a PMT. The simulations were then compared to measurements. Light output was measured by counting the photons detected by the PMT with the 3 x 10, 3 x 30, or 10 x 30 mm2 side coupled to the PMT, respectively. Our new code shows better agreement with the measured data than the current Geant4 code. The new code can also simulate reflector materials that are not pure specular or Lambertian reflectors, as was previously required. Our code is also more user friendly, as no detailed knowledge about the surfaces or light distributions is required from the user.

  14. Operation Sun Beam, Shot Small Boy. Project Officers report. Project 1. 9. Crater measurements

    SciTech Connect

    Rooke, A.D.; Davis, L.K.; Strange, J.N.

    1985-09-01

    The objectives of Project 1.9 were to obtain the dimensions of the apparent and true craters formed by the Small Boy event and to measure the permanent earth deformation occurring beyond the true crater boundary. Measurements were made of the apparent crater by aerial stereophotography and ground survey and of the true crater and subsurface zones of residual deformation by the excavation and mapping of an array of vertical, colored sand columns which were placed along one crater diameter prior to the shot. The results of the crater exploration are discussed, particularly the permanent compression of the medium beneath the true crater which was responsible for the major portion of the apparent and true crater volumes. Apparent and true crater dimensions are compared with those of previous cratering events.

  15. Development and Validation of Measures for Selecting Soldiers for the Officer Candidate School

    DTIC Science & Technology

    2011-08-01

    Class — Longitudinal, see Knapp & Heffner, 2009; for Select21, see Knapp & Tremble, 2007, for Profile of American Youth, see Moore , Pedlow, Krishnamurty...organization: A meta-analysis of antecedents, correlates, and consequences. Journal of Vocational Behavior, 61, 20-52. Moore , W., Pedlow, S., Krishnamurty, P... Basil Blackwell, Inc. Van Iddekinge, C.H., Putka, D.J., & Sager, C.E. (2005). Person-environment fit measures. In D.J. Knapp, C.E. Sager, & T.R

  16. Office Skills: Realistic Evaluation in Office Education Programs.

    ERIC Educational Resources Information Center

    Shinn, Larry

    1979-01-01

    To evaluate office occupations realistically, evaluation procedure criteria were developed using office simulation techniques. Grading methods given cover quality, quantity, attenance, tardiness, use of time, and cost of extra supplies, with grade penalties for performance deficiencies. (MF)

  17. Office blood pressure measurement practices among community health providers (medical and paramedical) in northern district of India

    PubMed Central

    Mohan, Bishav; Aslam, Naved; Ralhan, Upma; Sharma, Sarit; Gupta, Naveen; Singh, Vivudh Pratap; Takkar, Shibba; Wander, G.S.

    2014-01-01

    Introduction Hypertension is directly responsible for 57% of all stroke deaths and 24% of all coronary heart disease deaths in India. Appropriate blood pressure measurement techniques are the cornerstone of clinical acumen. Despite the clear guidelines on BP measurement technique, there seems to be large inter-observer variations. Aim & methods A prospective, observational study was done to assess the knowledge and to study the current practices of office BP measurement among the 400 medical and paramedical staff working in various hospitals of a northern district of India. A single observer under the supervision of investigators observed all the participants and a proforma was filled based on AHA guidelines. After observing BP measurement technique scoring was done (≤8 question correct = inaccurate practices, >9 questions correct = accurate practices). Similarly, the knowledge was assessed by giving a pretested questionnaire. Results 5.85 % of the medical staff had excellent knowledge and 80% of the doctors and 62% of the paramedical staff had good knowledge about BPM. Only 1.47% (3 doctors) and 0.5% (1 nurse) had accurate practices. There was no correlation between knowledge and practices. Conclusions We conclude that the right technique and knowledge of blood pressure measurement among community health providers is inadequate and warrants further interventions to improve. PMID:25173197

  18. Measurement of human pilot dynamic characteristics in flight simulation

    NASA Technical Reports Server (NTRS)

    Reedy, James T.

    1987-01-01

    Fast Fourier Transform (FFT) and Least Square Error (LSE) estimation techniques were applied to the problem of identifying pilot-vehicle dynamic characteristics in flight simulation. A brief investigation of the effects of noise, input bandwidth and system delay upon the FFT and LSE techniques was undertaken using synthetic data. Data from a piloted simulation conducted at NASA Ames Research Center was then analyzed. The simulation was performed in the NASA Ames Research Center Variable Stability CH-47B helicopter operating in fixed-basis simulator mode. The piloting task consisted of maintaining the simulated vehicle over a moving hover pad whose motion was described by a random-appearing sum of sinusoids. The two test subjects used a head-down, color cathode ray tube (CRT) display for guidance and control information. Test configurations differed in the number of axes being controlled by the pilot (longitudinal only versus longitudinal and lateral), and in the presence or absence of an important display indicator called an 'acceleration ball'. A number of different pilot-vehicle transfer functions were measured, and where appropriate, qualitatively compared with theoretical pilot- vehicle models. Some indirect evidence suggesting pursuit behavior on the part of the test subjects is discussed.

  19. Validating a driving simulator using surrogate safety measures.

    PubMed

    Yan, Xuedong; Abdel-Aty, Mohamed; Radwan, Essam; Wang, Xuesong; Chilakapati, Praveen

    2008-01-01

    Traffic crash statistics and previous research have shown an increased risk of traffic crashes at signalized intersections. How to diagnose safety problems and develop effective countermeasures to reduce crash rate at intersections is a key task for traffic engineers and researchers. This study aims at investigating whether the driving simulator can be used as a valid tool to assess traffic safety at signalized intersections. In support of the research objective, this simulator validity study was conducted from two perspectives, a traffic parameter (speed) and a safety parameter (crash history). A signalized intersection with as many important features (including roadway geometries, traffic control devices, intersection surroundings, and buildings) was replicated into a high-fidelity driving simulator. A driving simulator experiment with eight scenarios at the intersection were conducted to determine if the subjects' speed behavior and traffic risk patterns in the driving simulator were similar to what were found at the real intersection. The experiment results showed that speed data observed from the field and in the simulator experiment both follow normal distributions and have equal means for each intersection approach, which validated the driving simulator in absolute terms. Furthermore, this study used an innovative approach of using surrogate safety measures from the simulator to contrast with the crash analysis for the field data. The simulator experiment results indicated that compared to the right-turn lane with the low rear-end crash history record (2 crashes), subjects showed a series of more risky behaviors at the right-turn lane with the high rear-end crash history record (16 crashes), including higher deceleration rate (1.80+/-1.20 m/s(2) versus 0.80+/-0.65 m/s(2)), higher non-stop right-turn rate on red (81.67% versus 57.63%), higher right-turn speed as stop line (18.38+/-8.90 km/h versus 14.68+/-6.04 km/h), shorter following distance (30

  20. Measurement and simulation of thermoelectric efficiency for single leg

    SciTech Connect

    Hu, Xiaokai; Yamamoto, Atsushi Ohta, Michihiro; Nishiate, Hirotaka

    2015-04-15

    Thermoelectric efficiency measurements were carried out on n-type bismuth telluride legs with the hot-side temperature at 100 and 150°C. The electric power and heat flow were measured individually. Water coolant was utilized to maintain the cold-side temperature and to measure heat flow out of the cold side. Leg length and vacuum pressure were studied in terms of temperature difference across the leg, open-circuit voltage, internal resistance, and heat flow. Finite-element simulation on thermoelectric generation was performed in COMSOL Multiphysics, by inputting two-side temperatures and thermoelectric material properties. The open-circuit voltage and resistance were in good agreement between the measurement and simulation. Much larger heat flows were found in measurements, since they were comprised of conductive, convective, and radiative contributions. Parasitic heat flow was measured in the absence of bismuth telluride leg, and the conductive heat flow was then available. Finally, the maximum thermoelectric efficiency was derived in accordance with the electric power and the conductive heat flow.

  1. Measurement and simulation of thermoelectric efficiency for single leg.

    PubMed

    Hu, Xiaokai; Yamamoto, Atsushi; Ohta, Michihiro; Nishiate, Hirotaka

    2015-04-01

    Thermoelectric efficiency measurements were carried out on n-type bismuth telluride legs with the hot-side temperature at 100 and 150°C. The electric power and heat flow were measured individually. Water coolant was utilized to maintain the cold-side temperature and to measure heat flow out of the cold side. Leg length and vacuum pressure were studied in terms of temperature difference across the leg, open-circuit voltage, internal resistance, and heat flow. Finite-element simulation on thermoelectric generation was performed in COMSOL Multiphysics, by inputting two-side temperatures and thermoelectric material properties. The open-circuit voltage and resistance were in good agreement between the measurement and simulation. Much larger heat flows were found in measurements, since they were comprised of conductive, convective, and radiative contributions. Parasitic heat flow was measured in the absence of bismuth telluride leg, and the conductive heat flow was then available. Finally, the maximum thermoelectric efficiency was derived in accordance with the electric power and the conductive heat flow.

  2. Technical Performance Measures and Distributed-Simulation Training Systems

    DTIC Science & Technology

    2000-01-01

    Winter 2000 32 Piplani , L . K ., Mercer, J. G., & Roop, R. O. (1994). Systems acquisition manager’s guide for the use of models and simulations. Fort...tasks, moving on to learn advanced unit tasks, rein- forcement of p r e v i o u s l y learned tasks, and, finally, in- tegration of various combinations... Piplani , Mercer, and Roop, 1994), identifies numerous outcome-oriented, technical performance measures for use by acquisition managers of combat systems

  3. Microelectronics mounted on a piezoelectric transducer: method, simulations, and measurements.

    PubMed

    Johansson, Jonny; Delsing, Jerker

    2006-01-01

    This paper describes the design of a highly integrated ultrasound sensor where the piezoelectric ceramic transducer is used as the carrier for the driver electronics. Intended as one part in a complete portable, battery operated ultrasound sensor system, focus has been to achieve small size and low power consumption. An optimized ASIC driver stage is mounted directly on the piezoelectric transducer and connected using wire bond technology. The absence of wiring between driver and transducer provides excellent pulse control possibilities and eliminates the need for broad band matching networks. Estimates of the sensor power consumption are made based on the capacitive behavior of the piezoelectric transducer. System behavior and power consumption are simulated using SPICE models of the ultrasound transducer together with transistor level modelling of the driver stage. Measurements and simulations are presented of system power consumption and echo energy in a pulse echo setup. It is shown that the power consumption varies with the excitation pulse width, which also affects the received ultrasound energy in a pulse echo setup. The measured power consumption for a 16 mm diameter 4.4 MHz piezoelectric transducer varies between 95 microW and 130 microW at a repetition frequency of 1 kHz. As a lower repetition frequency gives a linearly lower power consumption, very long battery operating times can be achieved. The measured results come very close to simulations as well as estimated ideal minimum power consumption.

  4. Long-term vital sign measurement using a non-contact vital sign sensor inside an office cubicle setting.

    PubMed

    Hall, T; Malone, N A; Tsay, J; Lopez, J; Nguyen, T; Banister, R E; Lie, D Y C

    2016-08-01

    Heart and respiration rates can be wirelessly measured by extracting the phase shift caused by the periodic displacement of a patient's chest wall. We have developed a phased-array Doppler-based non-contact vital sign (NCVS) sensor capable of long-term vital signs monitoring using an automatic patient tracking and movement detection algorithm. Our NCVS sensor achieves non-contact heart rate monitoring with accuracies of over 90% (i.e, within ±5 Beats-Per-Minute vs. a reference sensor) across a large number of data points collected over various days of the week inside a typical office cubicle setting at a distance of 1.5 meters.

  5. Constraints in measuring body mass during simulated microgravity

    NASA Astrophysics Data System (ADS)

    Shimada, Kazuhito; Fujii, Yusaku

    2008-12-01

    The authors proposed "Space Scale" concept for measuring astronaut body mass in spacecraft on orbit. For the development of the flight hardware, accuracy/precision/operability verification tests under simulated microgravity are mandatory. We tested our device on a business jet flying parabolas to simulate microgravity. In addition to design constraints from microgravity, human factor engineering aspects also had to be dealt with. Methods (1) Mass was calculated based on (Mass) = (Force) x (Acceleration). (2) For Flight Test Series #1, a metal dummy mass of 9.37kg was used on parabolic flight tests. (3)For Flight Test Series #2, human subject mass was measured. (4) To eliminate acceleration noise from cabin vibration and air turbulence, data were rigorously filtered post-flight. Results With Flight Test Series #1, mass of the dummy was successfully derived with the standard uncertainty of 2.1 % for single measurement, and 0.7 % for the mean value of 12 measurements. Each measurement duration was less than 3sec., with rubber cord length reduction of 1 m. Conclusion The parabolic flight environment was a noisy acceleration field. Future studies should look more into human factor engineering aspects.

  6. Advances in the simulation and automated measurement of well-sorted granular material: 1. Simulation

    USGS Publications Warehouse

    Daniel Buscombe,; Rubin, David M.

    2012-01-01

    1. In this, the first of a pair of papers which address the simulation and automated measurement of well-sorted natural granular material, a method is presented for simulation of two-phase (solid, void) assemblages of discrete non-cohesive particles. The purpose is to have a flexible, yet computationally and theoretically simple, suite of tools with well constrained and well known statistical properties, in order to simulate realistic granular material as a discrete element model with realistic size and shape distributions, for a variety of purposes. The stochastic modeling framework is based on three-dimensional tessellations with variable degrees of order in particle-packing arrangement. Examples of sediments with a variety of particle size distributions and spatial variability in grain size are presented. The relationship between particle shape and porosity conforms to published data. The immediate application is testing new algorithms for automated measurements of particle properties (mean and standard deviation of particle sizes, and apparent porosity) from images of natural sediment, as detailed in the second of this pair of papers. The model could also prove useful for simulating specific depositional structures found in natural sediments, the result of physical alterations to packing and grain fabric, using discrete particle flow models. While the principal focus here is on naturally occurring sediment and sedimentary rock, the methods presented might also be useful for simulations of similar granular or cellular material encountered in engineering, industrial and life sciences.

  7. Advances in the simulation and automated measurement of well-sorted granular material: 1. Simulation

    NASA Astrophysics Data System (ADS)

    Buscombe, D.; Rubin, D. M.

    2012-06-01

    In this, the first of a pair of papers which address the simulation and automated measurement of well-sorted natural granular material, a method is presented for simulation of two-phase (solid, void) assemblages of discrete non-cohesive particles. The purpose is to have a flexible, yet computationally and theoretically simple, suite of tools with well constrained and well known statistical properties, in order to simulate realistic granular material as a discrete element model with realistic size and shape distributions, for a variety of purposes. The stochastic modeling framework is based on three-dimensional tessellations with variable degrees of order in particle-packing arrangement. Examples of sediments with a variety of particle size distributions and spatial variability in grain size are presented. The relationship between particle shape and porosity conforms to published data. The immediate application is testing new algorithms for automated measurements of particle properties (mean and standard deviation of particle sizes, and apparent porosity) from images of natural sediment, as detailed in the second of this pair of papers. The model could also prove useful for simulating specific depositional structures found in natural sediments, the result of physical alterations to packing and grain fabric, using discrete particle flow models. While the principal focus here is on naturally occurring sediment and sedimentary rock, the methods presented might also be useful for simulations of similar granular or cellular material encountered in engineering, industrial and life sciences.

  8. Analysis of In-Room mm-Wave Propagation: Directional Channel Measurements and Ray Tracing Simulations

    NASA Astrophysics Data System (ADS)

    Fuschini, F.; Häfner, S.; Zoli, M.; Müller, R.; Vitucci, E. M.; Dupleich, D.; Barbiroli, M.; Luo, J.; Schulz, E.; Degli-Esposti, V.; Thomä, R. S.

    2017-06-01

    Frequency bands above 6 GHz are being considered for future 5G wireless systems because of the larger bandwidth availability and of the smaller wavelength, which can ease the implementation of high-throughput massive MIMO schemes. However, great challenges are around the corner at each implementation level, including the achievement of a thorough multi-dimensional characterization of the mm-wave radio channel, which represents the base for the realization of reliable and high-performance radio interfaces and system architectures. The main properties of the indoor radio channel at 70 GHz, including angular and temporal dispersion as well as an assessment of the major interaction mechanisms, are investigated in this study by means of UWB directional measurements and ray tracing simulations in a reference, small-indoor office environment.

  9. High performance surface plasmon sensors: Simulations and measurements

    NASA Astrophysics Data System (ADS)

    Tiwari, Kunal; Sharma, Suresh C.; Hozhabri, Nader

    2015-09-01

    Through computer simulations and surface plasmon resonance (SPR) measurements, we establish optimum parameters for the design and fabrication of SPR sensors of high sensitivity, resolution, stability, and long decay-length evanescent fields. We present simulations and experimental SPR data for variety of sensors fabricated by using bimetal (Ag/Au) and multilayer waveguide-coupled Ag/Si3N4/Au structures. The simulations were carried out by using the transfer matrix method in MATLAB environment. Results are presented as functions of the thickness of the metal (Ag or Au) and the waveguide dielectric used in Ag/Si3N4/Au structures. Excellent agreement is observed between the simulations and experiments. For optimized thickness of the Si3N4 waveguide (150 nm), the sensor exhibits very high sensitivity to changes in the refractive index of analytes, Sn≈52°/R I U , extremely high resolution (F W H M ≤0.28° ) , and long penetration depth of evanescent fields (δ≥305 n m ) .

  10. Parametric analysis of open plan offices

    NASA Astrophysics Data System (ADS)

    Nogueira, Flavia F.; Viveiros, Elvira B.

    2002-11-01

    The workspace has been undergoing many changes. Open plan offices are being favored instead of ones of traditional design. In such offices, workstations are separated by partial height barriers, which allow a certain degree of visual privacy and some sound insulation. The challenge in these offices is to provide acoustic privacy for the workstations. Computer simulation was used as a tool for this investigation. Two simple models were generated and their results compared to experimental data measured in two real offices. After validating the approach, models with increasing complexity were generated. Lastly, an ideal office with 64 workstations was created and a parametric survey performed. Nine design parameters were taken as variables and the results are discussed in terms of sound pressure level, in octave bands, and intelligibility index.

  11. In-flight and simulated aircraft fuel temperature measurements

    NASA Technical Reports Server (NTRS)

    Svehla, Roger A.

    1990-01-01

    Fuel tank measurements from ten flights of an L1011 commercial aircraft are reported for the first time. The flights were conducted from 1981 to 1983. A thermocouple rake was installed in an inboard wing tank and another in an outboard tank. During the test periods of either 2 or 5 hr, at altitudes of 10,700 m (35,000 ft) or higher, either the inboard or the outboard tank remained full. Fuel temperature profiles generally developed in the expected manner. The bulk fuel was mixed by natural convection to a nearly uniform temperature, especially in the outboard tank, and a gradient existed at the bottom conduction zone. The data indicated that when full, the upper surface of the inboard tank was wetted and the outboard tank was unwetted. Companion NASA Lewis Research Center tests were conducted in a 0.20 cubic meter (52 gal) tank simulator of the outboard tank, chilled on the top and bottom, and insulated on the sides. Even though the simulator tank had no internal components corresponding to the wing tank, temperatures agreed with the flight measurements for wetted upper surface conditions, but not for unwetted conditions. It was concluded that if boundary conditions are carefully controlled, simulators are a useful way of evaluating actual flight temperatures.

  12. Diffuse photon density wave measurements and Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Kuzmin, Vladimir L.; Neidrauer, Michael T.; Diaz, David; Zubkov, Leonid A.

    2015-10-01

    Diffuse photon density wave (DPDW) methodology is widely used in a number of biomedical applications. Here, we present results of Monte Carlo simulations that employ an effective numerical procedure based upon a description of radiative transfer in terms of the Bethe-Salpeter equation. A multifrequency noncontact DPDW system was used to measure aqueous solutions of intralipid at a wide range of source-detector separation distances, at which the diffusion approximation of the radiative transfer equation is generally considered to be invalid. We find that the signal-noise ratio is larger for the considered algorithm in comparison with the conventional Monte Carlo approach. Experimental data are compared to the Monte Carlo simulations using several values of scattering anisotropy and to the diffusion approximation. Both the Monte Carlo simulations and diffusion approximation were in very good agreement with the experimental data for a wide range of source-detector separations. In addition, measurements with different wavelengths were performed to estimate the size and scattering anisotropy of scatterers.

  13. Diffuse photon density wave measurements and Monte Carlo simulations.

    PubMed

    Kuzmin, Vladimir L; Neidrauer, Michael T; Diaz, David; Zubkov, Leonid A

    2015-10-01

    Diffuse photon density wave (DPDW) methodology is widely used in a number of biomedical applications. Here, we present results of Monte Carlo simulations that employ an effective numerical procedure based upon a description of radiative transfer in terms of the Bethe–Salpeter equation. A multifrequency noncontact DPDW system was used to measure aqueous solutions of intralipid at a wide range of source–detector separation distances, at which the diffusion approximation of the radiative transfer equation is generally considered to be invalid. We find that the signal–noise ratio is larger for the considered algorithm in comparison with the conventional Monte Carlo approach. Experimental data are compared to the Monte Carlo simulations using several values of scattering anisotropy and to the diffusion approximation. Both the Monte Carlo simulations and diffusion approximation were in very good agreement with the experimental data for a wide range of source–detector separations. In addition, measurements with different wavelengths were performed to estimate the size and scattering anisotropy of scatterers.

  14. Organ radiation exposure with EOS: GATE simulations versus TLD measurements

    NASA Astrophysics Data System (ADS)

    Clavel, A. H.; Thevenard-Berger, P.; Verdun, F. R.; Létang, J. M.; Darbon, A.

    2016-03-01

    EOS® is an innovative X-ray imaging system allowing the acquisition of two simultaneous images of a patient in the standing position, during the vertical scan of two orthogonal fan beams. This study aimed to compute organs radiation exposure to a patient, in the particular geometry of this system. Two different positions of the patient in the machine were studied, corresponding to postero-anterior plus left lateral projections (PA-LLAT) and antero-posterior plus right lateral projections (AP-RLAT). To achieve this goal, a Monte-Carlo simulation was developed based on a GATE environment. To model the physical properties of the patient, a computational phantom was produced based on computed tomography scan data of an anthropomorphic phantom. The simulations provided several organs doses, which were compared to previously published dose results measured with Thermo Luminescent Detectors (TLD) in the same conditions and with the same phantom. The simulation results showed a good agreement with measured doses at the TLD locations, for both AP-RLAT and PA-LLAT projections. This study also showed that the organ dose assessed only from a sample of locations, rather than considering the whole organ, introduced significant bias, depending on organs and projections.

  15. Simulation and measurement of transcranial near infrared light penetration

    NASA Astrophysics Data System (ADS)

    Yue, Lan; Monge, Manuel; Ozgur, Mehmet H.; Murphy, Kevin; Louie, Stan; Miller, Carol A.; Emami, Azita; Humayun, Mark S.

    2015-03-01

    We are studying the transmission of LED array-emitted near-infrared (NIR) light through human tissues. Herein, we simulated and measured transcranial NIR penetration in highly scattering human head tissues. Using finite element analysis, we simulated photon diffusion in a multilayered 3D human head model that consists of scalp, skull, cerebral spinal fluid, gray matter and white matter. The optical properties of each layer, namely scattering and absorption coefficient, correspond to the 850 nm NIR light. The geometry of the model is minimally modified from the IEEE standard and the multiple LED emitters in an array were evenly distributed on the scalp. Our results show that photon distribution produced by the array exhibits little variation at similar brain depth, suggesting that due to strong scattering effects of the tissues, discrete spatial arrangements of LED emitters in an array has the potential to create a quasi-radially symmetrical illumination field. Measurements on cadaveric human head tissues excised from occipital, parietal, frontal and temporal regions show that illumination with an 850 nm LED emitter rendered a photon flux that closely follows simulation results. In addition, prolonged illumination of LED emitted NIR showed minimal thermal effects on the brain.

  16. Predicting out-of-office blood pressure level using repeated measurements in the clinic: an observational cohort study.

    PubMed

    Sheppard, James P; Holder, Roger; Nichols, Linda; Bray, Emma; Hobbs, F D Richard; Mant, Jonathan; Little, Paul; Williams, Bryan; Greenfield, Sheila; McManus, Richard J

    2014-11-01

    Identification of people with lower (white-coat effect) or higher (masked effect) blood pressure at home compared to the clinic usually requires ambulatory or home monitoring. This study assessed whether changes in SBP with repeated measurement at a single clinic predict subsequent differences between clinic and home measurements. This study used an observational cohort design and included 220 individuals aged 35-84 years, receiving treatment for hypertension, but whose SBP was not controlled. The characteristics of change in SBP over six clinic readings were defined as the SBP drop, the slope and the quadratic coefficient using polynomial regression modelling. The predictive abilities of these characteristics for lower or higher home SBP readings were investigated with logistic regression and repeated operating characteristic analysis. The single clinic SBP drop was predictive of the white-coat effect with a sensitivity of 90%, specificity of 50%, positive predictive value of 56% and negative predictive value of 88%. Predictive values for the masked effect and those of the slope and quadratic coefficient were slightly lower, but when the slope and quadratic variables were combined, the sensitivity, specificity, positive and negative predictive values for the masked effect were improved to 91, 48, 24 and 97%, respectively. Characteristics obtainable from multiple SBP measurements in a single clinic in patients with treated hypertension appear to reasonably predict those unlikely to have a large white-coat or masked effect, potentially allowing better targeting of out-of-office monitoring in routine clinical practice.

  17. Predicting out-of-office blood pressure level using repeated measurements in the clinic: an observational cohort study

    PubMed Central

    Sheppard, James P.; Holder, Roger; Nichols, Linda; Bray, Emma; Hobbs, F.D. Richard; Mant, Jonathan; Little, Paul; Williams, Bryan; Greenfield, Sheila; McManus, Richard J.

    2014-01-01

    Objectives: Identification of people with lower (white-coat effect) or higher (masked effect) blood pressure at home compared to the clinic usually requires ambulatory or home monitoring. This study assessed whether changes in SBP with repeated measurement at a single clinic predict subsequent differences between clinic and home measurements. Methods: This study used an observational cohort design and included 220 individuals aged 35–84 years, receiving treatment for hypertension, but whose SBP was not controlled. The characteristics of change in SBP over six clinic readings were defined as the SBP drop, the slope and the quadratic coefficient using polynomial regression modelling. The predictive abilities of these characteristics for lower or higher home SBP readings were investigated with logistic regression and repeated operating characteristic analysis. Results: The single clinic SBP drop was predictive of the white-coat effect with a sensitivity of 90%, specificity of 50%, positive predictive value of 56% and negative predictive value of 88%. Predictive values for the masked effect and those of the slope and quadratic coefficient were slightly lower, but when the slope and quadratic variables were combined, the sensitivity, specificity, positive and negative predictive values for the masked effect were improved to 91, 48, 24 and 97%, respectively. Conclusion: Characteristics obtainable from multiple SBP measurements in a single clinic in patients with treated hypertension appear to reasonably predict those unlikely to have a large white-coat or masked effect, potentially allowing better targeting of out-of-office monitoring in routine clinical practice. PMID:25144295

  18. Preliminary effects of real-world factors on the recovery and exploitation of forensic impurity profiles of a nerve-agent simulant from office media.

    PubMed

    Fraga, Carlos G; Sego, Landon H; Hoggard, Jamin C; Acosta, Gabriel A Pérez; Viglino, Emilie A; Wahl, Jon H; Synovec, Robert E

    2012-12-28

    Dimethyl methylphosphonate (DMMP) was used as a chemical threat agent (CTA) simulant for a first look at the effects of real-world factors on the recovery and exploitation of a CTA's impurity profile for source matching. Four stocks of DMMP having different impurity profiles were disseminated as aerosols onto cotton, painted wall board, and nylon coupons according to a thorough experimental design. The DMMP-exposed coupons were then solvent extracted and analyzed for DMMP impurities by comprehensive 2D gas chromatography/mass spectrometry (GC×GC/MS). The similarities between the coupon DMMP impurity profiles and the known (reference) DMMP profiles were measured by dot products of the coupon profiles and known profiles and by score values obtained from principal component analysis. One stock, with a high impurity-profile selectivity value of 0.9 out of 1, had 100% of its respective coupons correctly classified and no false positives from other coupons. Coupons from the other three stocks with low selectivity values (0.0073, 0.012, and 0.018) could not be sufficiently distinguished from one another for reliable matching to their respective stocks. The results from this work support that: (1) extraction solvents, if not appropriately selected, can have some of the same impurities present in a CTA reducing a CTA's useable impurity profile, (2) low selectivity among a CTA's known impurity profiles will likely make definitive source matching impossible in some real-world conditions, (3) no detrimental chemical-matrix interference was encountered during the analysis of actual office media, (4) a short elapsed time between release and sample storage is advantageous for the recovery of the impurity profile because it minimizes volatilization of forensic impurities, and (5) forensic impurity profiles weighted toward higher volatility impurities are more likely to be altered by volatilization following CTA exposure.

  19. Preliminary Effects of Real-World Factors on the Recovery and Exploitation of Forensic Impurity Profiles of a Nerve-Agent Simulant from Office Media

    SciTech Connect

    Fraga, Carlos G.; Sego, Landon H.; Hoggard, Jamin C.; Perez Acosta, Gabriel A.; Viglino, Emilie A.; Wahl, Jon H.; Synovec, Robert E.

    2012-12-28

    Dimethyl methylphosphonate (DMMP) was used as a chemical threat agent (CTA) simulant for a first look at the effects of real-world factors on the recovery and exploitation of a CTA’s impurity profile for source matching. Four stocks of DMMP having different impurity profiles were disseminated as aerosols onto cotton, painted wall board, and nylon coupons according to a thorough experimental design. The DMMP-exposed coupons were then solvent extracted and analyzed for DMMP impurities by comprehensive 2-D gas chromatography/mass spectrometry (GC×GC/MS). The similarities between the coupon DMMP impurity profiles and the known (reference) DMMP profiles were measured by dot products of the coupon profiles and known profiles and by score values obtained from principal component analysis. One stock, with a high impurity-profile selectivity value of 0.9 out of 1, had 100% of its respective coupons correctly classified and no false positives from other coupons. Coupons from the other three stocks with low selectivity values (0.0073, 0.012, and 0.018) could not be sufficiently distinguished from one another for reliable matching to their respective stocks. The results from this work support that: (1) extraction solvents, if not appropriately selected, can have some of the same impurities present in a CTA reducing a CTA’s useable impurity profile, (2) low selectivity among a CTA’s known impurity profiles will likely make definitive source matching impossible in some real-world conditions, (3) no detrimental chemical-matrix interference was encountered during the analysis of actual office media, (4) a short elapsed time between release and sample storage is advantageous for the recovery of the impurity profile because it minimizes volatilization of forensic impurities, and (5) forensic impurity profiles weighted towards higher volatility impurities are more likely to be altered by volatilization following CTA exposure.

  20. Evaluation of Intersection Traffic Control Measures through Simulation

    NASA Astrophysics Data System (ADS)

    Asaithambi, Gowri; Sivanandan, R.

    2015-12-01

    Modeling traffic flow is stochastic in nature due to randomness in variables such as vehicle arrivals and speeds. Due to this and due to complex vehicular interactions and their manoeuvres, it is extremely difficult to model the traffic flow through analytical methods. To study this type of complex traffic system and vehicle interactions, simulation is considered as an effective tool. Application of homogeneous traffic models to heterogeneous traffic may not be able to capture the complex manoeuvres and interactions in such flows. Hence, a microscopic simulation model for heterogeneous traffic is developed using object oriented concepts. This simulation model acts as a tool for evaluating various control measures at signalized intersections. The present study focuses on the evaluation of Right Turn Lane (RTL) and Channelised Left Turn Lane (CLTL). A sensitivity analysis was performed to evaluate RTL and CLTL by varying the approach volumes, turn proportions and turn lane lengths. RTL is found to be advantageous only up to certain approach volumes and right-turn proportions, beyond which it is counter-productive. CLTL is found to be advantageous for lower approach volumes for all turn proportions, signifying the benefits of CLTL. It is counter-productive for higher approach volume and lower turn proportions. This study pinpoints the break-even points for various scenarios. The developed simulation model can be used as an appropriate intersection lane control tool for enhancing the efficiency of flow at intersections. This model can also be employed for scenario analysis and can be valuable to field traffic engineers in implementing vehicle-type based and lane-based traffic control measures.

  1. Measurement and simulation of the RHIC abort kicker longitudinal impedence

    SciTech Connect

    Abreu,N.P.; Hahn,H.; Choi, E.

    2009-09-01

    In face of the new upgrades for RHIC the longitudinal impedance of the machine plays an important role in setting the threshold for instabilities and the efficacy of some systems. In this paper we describe the measurement of the longitudinal impedance of the abort kicker for RHIC as well as computer simulations of the structure. The impedance measurement was done by the S{sub 21} wire method covering the frequency range from 9 kHz to 2.5 GHz. We observed a sharp resonance peak around 10 MHz and a broader peak around 20 MHz in both, the real and imaginary part, of the Z/n. These two peaks account for a maximum imaginary longitudinal impedance of j15 {Omega}, a value an order of magnitude larger than the estimated value of j0.2 {Omega}, which indicates that the kicker is one of the main sources of longitudinal impedance in the machine. A computer model was constructed for simulations in the CST MWS program. Results for the magnet input and the also the beam impedance are compared to the measurements. A more detail study of the system properties and possible changes to reduce the coupling impedance are presented.

  2. Computer simulation of three-dimensional directional response measurements

    NASA Astrophysics Data System (ADS)

    Warren, Daniel M.

    2005-09-01

    Early in the development of methods for measuring the three-dimensional directional response of hearing aids, there were many questions on how to distribute sound sources over the sphere. The method had to be accurate, yet practical to implement. Decisions on the scheme for distributing sound sources, the density of sound sources, and the weighting of results from each source have impact on accuracy. A simulation of the directional response of an array of microphones in the direct and scattered acoustic field near a rigid sphere was created and used to evaluate various means of distributing sound sources.

  3. Numerical simulation in alternating current field measurement inducer design

    NASA Astrophysics Data System (ADS)

    Zhou, Zhixiong; Zheng, Wenpei

    2017-02-01

    The present work develops a numerical simulation model to evaluate the magnetic field perturbation of a twin coil alternating current field measurement (ACFM) inducer passing above a surface-breaking crack for the purpose of enhanced crack detection. Model predictions show good agreement with experimental data, verifying the accuracy of the model. The model includes the influence of various parameters, such as core dimensions and core positions on the perturbed magnetic field above a crack. Optimized design parameters for a twin coil inducer are given according to the analysis results, which provide for a greatly improved detection effect.

  4. Upper trapezius muscle activity in healthy office workers: reliability and sensitivity of occupational exposure measures to differences in sex and hand dominance.

    PubMed

    Marker, Ryan J; Balter, Jaclyn E; Nofsinger, Micaela L; Anton, Dan; Fethke, Nathan B; Maluf, Katrina S

    2016-09-01

    Patterns of cervical muscle activity may contribute to overuse injuries in office workers. The purpose of this investigation was to characterise patterns of upper trapezius muscle activity in pain-free office workers using traditional occupational exposure measures and a modified Active Amplitude Probability Distribution Function (APDF), which considers only periods of active muscle contraction. Bilateral trapezius muscle activity was recorded in 77 pain-free office workers for 1-2 full days in their natural work environment. Mean amplitude, gap frequency, muscular rest and Traditional and Active APDF amplitudes were calculated. All measures demonstrated fair to substantial reliability. Dominant muscles demonstrated higher amplitudes of activity and less muscular rest compared to non-dominant, and women demonstrated less muscular rest with no significant difference in amplitude assessed by Active APDF compared to men. These findings provide normative data to identify atypical motor patterns that may contribute to persistence or recurrence of neck pain in office workers. Practitioner Summary: Upper trapezius muscle activity was characterised in a large cohort of pain-free workers using electromyographic recordings from office environments. Dominant muscles demonstrated higher activity and less rest than non-dominant, and women demonstrated less rest than men. Results may be used to identify atypical trapezius muscle activity in office workers.

  5. Measurements and simulation on the comfort of forklifts

    NASA Astrophysics Data System (ADS)

    Verschoore, R.; Pieters, J. G.; Pollet, I. V.

    2003-09-01

    In order to determine the influence of some parameters of a forklift such as the road profile, the tyre characteristics, the riding comfort, etc., measurements carried out on a forklift with different tyres and seats were evaluated using different standards and methods. In addition, a simulation model was developed and used to investigate the influence of these parameters. Simulations and test run results showed good agreement. The comparison of the results obtained with several methods of comfort evaluation and a series of tests showed that they nearly all resulted in the same classification. However, the results obtained with different methods could not always be compared among themselves. Solid tyres were found to be more comfortable than pneumatic ones because of their high damping. The negative influence of higher stiffness was smaller than the positive influence of higher damping. The simulations pointed out that for a global general investigation about comfort, the influence of the horizontal tyre stiffness and damping can be neglected. Also the seat characteristics could be linearized. When the stability of the forklift has to be investigated, the horizontal forces must also be considered.

  6. SIMULATED FARADAY ROTATION MEASURES TOWARD HIGH GALACTIC LATITUDES

    SciTech Connect

    Akahori, Takuya; Kim, Jongsoo; Ryu, Dongsu; Gaensler, B. M. E-mail: akahori@physics.usyd.edu.au E-mail: ryu@canopus.cnu.ac.kr

    2013-04-20

    We study the Faraday rotation measure (RM) due to the Galactic magnetic field (GMF) toward high Galactic latitudes. The RM arises from the global, regular component as well as from the turbulent, random component of the GMF. We model the former based on observations and the latter using the data of magnetohydrodynamic turbulence simulations. For a large number of different GMF models, we produce mock RM maps around the Galactic poles and calculate various statistical quantities with the RM maps. We find that the observed medians of RMs toward the north and south Galactic poles, {approx}0.0 {+-} 0.5 rad m{sup -2} and {approx} + 6.3 {+-} 0.5 rad m{sup -2}, are difficult to explain with any of our many alternate GMF models. The standard deviation of observed RMs, {approx}9 rad m{sup -2}, is clearly larger than that of simulated RMs. The second-order structure function of observed RMs is substantially larger than that of simulated RMs, especially at small angular scales. We discuss other possible contributions to RM toward high Galactic latitudes. Besides observational errors and the intrinsic RM of background radio sources against which RM is observed, we suggest that the RM due to the intergalactic magnetic field may account for a substantial fraction of the observed RM. Finally, we note that reproducing the observed medians may require additional components or/and structures of the GMF that are not present in our models.

  7. Study on the measuring distance for blood glucose infrared spectral measuring by Monte Carlo simulation

    NASA Astrophysics Data System (ADS)

    Li, Xiang

    2016-10-01

    Blood glucose monitoring is of great importance for controlling diabetes procedure and preventing the complications. At present, the clinical blood glucose concentration measurement is invasive and could be replaced by noninvasive spectroscopy analytical techniques. Among various parameters of optical fiber probe used in spectrum measuring, the measurement distance is the key one. The Monte Carlo technique is a flexible method for simulating light propagation in tissue. The simulation is based on the random walks that photons make as they travel through tissue, which are chosen by statistically sampling the probability distributions for step size and angular deflection per scattering event. The traditional method for determine the optimal distance between transmitting fiber and detector is using Monte Carlo simulation to find out the point where most photons come out. But there is a problem. In the epidermal layer there is no artery, vein or capillary vessel. Thus, when photons propagate and interactive with tissue in epidermal layer, no information is given to the photons. A new criterion is proposed to determine the optimal distance, which is named effective path length in this paper. The path length of each photons travelling in dermis is recorded when running Monte-Carlo simulation, which is the effective path length defined above. The sum of effective path length of every photon at each point is calculated. The detector should be place on the point which has most effective path length. Then the optimal measuring distance between transmitting fiber and detector is determined.

  8. Measurements of contrast sensitivity by an adaptive optics visual simulator

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Tatsuo; Ucikawa, Keiji

    2015-08-01

    We developed an adaptive optics visual simulator (AOVS) to study the relationship between the contrast sensitivity and higher-order wavefront aberrations of human eyes. A desired synthetic aberration was virtually generated on a subject eye by the AOVS, and red laser light was used to measure the aberrations. The contrast sensitivity was measured in a psychophysical experiment using visual stimulus patterns provided by a large-contrast-range imaging system, which included two liquid crystal displays illuminated by red light emitting diodes from the backside. The diameter of the pupil was set to 4 mm by an artificial aperture, and the retinal illuminance of the stimulus image was controlled to 10 Td. Experiments conducted with four normal subjects revealed that their contrast sensitivity to a high-spatial-frequency vertical sinusoidal grating pattern was lower in the presence of a horizontal coma aberration than in the presence of a vertical coma or no aberrations ( p < 0.02, Nagai method).

  9. Hanford Sludge Simulant Selection for Soil Mechanics Property Measurement

    SciTech Connect

    Wells, Beric E.; Russell, Renee L.; Mahoney, Lenna A.; Brown, Garrett N.; Rinehart, Donald E.; Buchmiller, William C.; Golovich, Elizabeth C.; Crum, Jarrod V.

    2010-03-23

    The current System Plan for the Hanford Tank Farms uses relaxed buoyant displacement gas release event (BDGRE) controls for deep sludge (i.e., high level waste [HLW]) tanks, which allows the tank farms to use more storage space, i.e., increase the sediment depth, in some of the double-shell tanks (DSTs). The relaxed BDGRE controls are based on preliminary analysis of a gas release model from van Kessel and van Kesteren. Application of the van Kessel and van Kesteren model requires parametric information for the sediment, including the lateral earth pressure at rest and shear modulus. No lateral earth pressure at rest and shear modulus in situ measurements for Hanford sludge are currently available. The two chemical sludge simulants will be used in follow-on work to experimentally measure the van Kessel and van Kesteren model parameters, lateral earth pressure at rest, and shear modulus.

  10. Measurement scheme and simulation for the main reflector of FAST

    NASA Astrophysics Data System (ADS)

    Hu, Jinwen; Nan, Rendong; Zhu, Lichun; Li, Xinyi

    2013-09-01

    FAST (five-hundred-meter aperture spherical radio telescope) is a radio telescope being built in a karst depression in Guizhou Province of China, which will be the largest single dish radio telescope in the world [1]. The reflector of the telescope is composed of over 4000 panels, and each panel could adjust its position according to observation requirements. During observations, panels in the illuminated area could form a paraboloid to correct spherical aberration [2]. Therefore, accurate measurement of the positions of panels is crucial for the operation of the telescope. In this paper, we introduce the measurement scheme for the reflector of FAST, and simulate its accuracy using direct linear transform, Gauss-Newton algorithm, Levenberg-Marquardt algorithm and an algorithm referred to as multi-point algorithm. Advantages and disadvantages of using these four methods are compared for analysis at different locations of the panels on the reflector, and suggestions are given in choosing algorithms in implementation.

  11. Quantitative Morphology Measures in Galaxies: Ground-Truthing from Simulations

    NASA Astrophysics Data System (ADS)

    Narayanan, Desika T.; Abruzzo, Matthew W.; Dave, Romeel; Thompson, Robert

    2017-01-01

    The process of galaxy assembly is a prevalent question in astronomy; there are a variety of potentially important effects, including baryonic accretion from the intergalactic medium, as well as major galaxy mergers. Recent years have ushered in the development of quantitative measures of morphology such as the Gini coefficient (G), the second-order moment of the brightest quintile of a galaxy’s light (M20), and the concentration (C), asymmetry (A), and clumpiness (S) of galaxies. To investigate the efficacy of these observational methods at identifying major mergers, we have run a series of very high resolution cosmological zoom simulations, and coupled these with 3D Monte Carlo dust radiative transfer. Our methodology is powerful in that it allows us to “observe” the simulation as an observer would, while maintaining detailed knowledge of the true merger history of the galaxy. In this presentation, we will present our main results from our analysis of these quantitative morphology measures, with a particular focus on high-redshift (z>2) systems.

  12. Traceability of spectroradiometric measurements of multiport UV solar simulators

    NASA Astrophysics Data System (ADS)

    Dai, Cai-hong; Wu, Zhi-feng; Qi, Xiao-jin; Ye, Jing; Chen, Bin-hua

    2013-08-01

    A special multiport UV solar simulator was designed at National Institute of Metrology (NIM), and a set of UVA and UVA+B optical filters were developed to satisfy the spectral distribution specifications of COLIPA SPF and JCIA Persistent Pigmentation Darkening (PPD) test methods. The other purpose of this apparatus is used to calibrate the UVA and UVA+B irradiance or dose of broadband UV radiometers. The response of a double grating spectroradiometer with a 5.8 mm entrance aperture from 250nm to 800nm was calibrated using a 1000W spectral irradiance standard lamp at a distance of 500 mm, and the value of quantities of the developed system is traceable to the national primary standard of spectral irradiance of NIM. The system wavelength was checked using a low-pressure mercury lamp. The spectral response of each port was measured from 250nm to 800nm in 1nm steps. Experiment results showed that the percentage relative cumulative erythemal effectiveness (% RCEE) and UVA measurement waveband values of the multiport UV solar simulator are within the specified limits. The source spectrum is smooth and continuous, and the energy below 290nm is less than 0.1%.

  13. Photolysis frequency measurements in a sunlit simulation chamber

    NASA Astrophysics Data System (ADS)

    Bohn, B.; Rohrer, F.; Brauers, T.; Wahner, A.

    2003-04-01

    The simulation chamber SAPHIR at Forschungszentrum Jülich provides a unique tool to investigate atmospheric photochemistry under realistic ambient conditions. However, while transport processes and chemical composition are controlled more easily compared to field measurements, the radiation field within the chamber is more complex. Construction elements produce shady areas while the Teflon walls and the chamber ground are scattering and reflecting light. On the other hand, actinic flux or photolysis frequency measurements with a spectral radiometer or filterradiometers can only be made at selected points where the measured quantities are not representative for the chamber as a whole. In this work we describe a method to derive mean photolysis frequencies for SAPHIR based on solar actinic flux measurements outside of the chamber. The calculation is based on a distinction between direct and diffuse solar radiation, a numerical model describing the illumination and calibrations using the whole chamber as a chemical actinometer by observing the photochemical NO_2-NO-O_3 equilibrium under various external conditions.

  14. Cosmic-ray neutron simulations and measurements in Taiwan.

    PubMed

    Chen, Wei-Lin; Jiang, Shiang-Huei; Sheu, Rong-Jiun

    2014-10-01

    This study used simulations of galactic cosmic ray in the atmosphere to investigate the neutron background environment in Taiwan, emphasising its altitude dependence and spectrum variation near interfaces. The calculated results were analysed and compared with two measurements. The first measurement was a mobile neutron survey from sea level up to 3275 m in altitude conducted using a car-mounted high-sensitivity neutron detector. The second was a previous measured result focusing on the changes in neutron spectra near air/ground and air/water interfaces. The attenuation length of cosmic-ray neutrons in the lower atmosphere was estimated to be 163 g cm(-2) in Taiwan. Cosmic-ray neutron spectra vary with altitude and especially near interfaces. The determined spectra near the air/ground and air/water interfaces agree well with measurements for neutrons below 10 MeV. However, the high-energy portion of spectra was observed to be much higher than our previous estimation. Because high-energy neutrons contribute substantially to a dose evaluation, revising the annual sea-level effective dose from cosmic-ray neutrons at ground level in Taiwan to 35 μSv, which corresponds to a neutron flux of 5.30 × 10(-3) n cm(-2) s(-1), was suggested.

  15. Measuring Impact of U.S. DOE Geothermal Technologies Office Funding: Considerations for Development of a Geothermal Resource Reporting Metric

    SciTech Connect

    Young, Katherine R.; Wall, Anna M.; Dobson, Patrick F.; Bennett, Mitchell; Segneri, Brittany

    2015-04-25

    This paper reviews existing methodologies and reporting codes used to describe extracted energy resources such as coal and oil and describes a comparable proposed methodology to describe geothermal resources. The goal is to provide the U.S. Department of Energy's (DOE) Geothermal Technologies Office (GTO) with a consistent and comprehensible means of assessing the impacts of its funding programs. This framework will allow for GTO to assess the effectiveness of research, development, and deployment (RD&D) funding, prioritize funding requests, and demonstrate the value of RD&D programs to the U.S. Congress. Standards and reporting codes used in other countries and energy sectors provide guidance to inform development of a geothermal methodology, but industry feedback and our analysis suggest that the existing models have drawbacks that should be addressed. In order to formulate a comprehensive metric for use by GTO, we analyzed existing resource assessments and reporting methodologies for the geothermal, mining, and oil and gas industries, and we sought input from industry, investors, academia, national labs, and other government agencies. Using this background research as a guide, we describe a methodology for assessing and reporting on GTO funding according to resource knowledge and resource grade (or quality). This methodology would allow GTO to target funding or measure impact by progression of projects or geological potential for development.

  16. Lung function measures following simulated wildland firefighter exposures.

    PubMed

    Ferguson, Matthew D; Semmens, Erin O; Weiler, Emily; Domitrovich, Joe; French, Mary; Migliaccio, Christopher; Palmer, Charles; Dumke, Charles; Ward, Tony

    2017-09-01

    Across the world, biomass smoke is a major source of air pollution and is linked with a variety of adverse health effects. This is particularly true in the western U.S. where wood smoke from wildland forest fires are a significant source of PM2.5. Wildland firefighters are impacted as they experience elevated PM2.5 concentrations over extended periods of time, often occurring during physical exertion. Various epidemiological studies have investigated wood smoke impacts on human health, including occupational field exposures experienced by wildland firefighters. As there are numerous challenges in carrying out these field studies, having the ability to research the potential health impacts to this occupational cohort in a controlled setting would provide important information that could be translated to the field setting. To this end, we have carried out a simulated wildland firefighter exposure study in a wood smoke inhalation facility. Utilizing a randomized crossover trial design, we exposed 10 participants once to clean filtered-air, 250 µg/m(3), and 500 µg/m(3) wood stove-generated wood smoke PM2.5. Participants exercised on a treadmill at an absolute intensity designed to simulate wildland firefighting for 1.5 hr. In addition to measured PM2.5 smoke concentrations, mean levels of CO2, CO, and % relative humidity were continuously monitored and recorded and were representative of occupational "real-world" exposures. Pulmonary function was measured at three time points: before, immediately after, and 1-hr post-exposure. Although there were some reductions in FVC, FEV1, and FVC:FEV1 measures, results of the spirometry testing did not show significant changes in lung function. The development of this wood smoke inhalational facility provides a platform to further address unique research questions related to wood smoke exposures and associated adverse health effects.

  17. Measurements and simulations of water transport in maize plants

    NASA Astrophysics Data System (ADS)

    Heinlein, Florian; Klein, Christian; Thieme, Christoph; Priesack, Eckart

    2017-04-01

    In Central Europe climate change will become manifest in the increase of extreme weather events like flash floods, heat waves and summer droughts, and in a shift of precipitation towards winter months. Therefore, regional water availability will alter which has an effect on future crop growth, water use efficiency and yields. To better estimate these effects accurate model descriptions of transpiration and other parts of the water balance are important. In this study, we determined transpiration of four maize plants on a field of the research station Scheyern (about 40km North of Munich) by means of sap flow measurement devices (ICQ International Pty Ltd, Australia) using the Heat-Ratio-Method: two temperature probes, 0.5 cm above and below a heater, detect a heat pulse and its speed which facilitates the calculation of sap flow. Additionally, high resolution changes of stem diameters were measured with dendrometers (DD-S, Ecomatik). The field was also situated next to an eddy covariance station which provided latent heat fluxes from the soil-plant system. We also performed terrestrial laser scans of the respective plants to extract the plant architectures. These structures serve as input for our mechanistic transpiration model simulating the water transport within the plant. This model, which has already been successfully applied to single Fagus sylvatica L. trees, was adapted to agricultural plants such as maize. The basic principle of this model is to solve a 1-D Richards equation along the graph of the single plants. A comparison between the simulations and the measurements is presented and discussed.

  18. Measurement and simulation of the TRR BNCT beam parameters

    NASA Astrophysics Data System (ADS)

    Bavarnegin, Elham; Sadremomtaz, Alireza; Khalafi, Hossein; Kasesaz, Yaser; Golshanian, Mohadeseh; Ghods, Hossein; Ezzati, Arsalan; Keyvani, Mehdi; Haddadi, Mohammad

    2016-09-01

    Recently, the configuration of the Tehran Research Reactor (TRR) thermal column has been modified and a proper thermal neutron beam for preclinical Boron Neutron Capture Therapy (BNCT) has been obtained. In this study, simulations and experimental measurements have been carried out to identify the BNCT beam parameters including the beam uniformity, the distribution of the thermal neutron dose, boron dose, gamma dose in a phantom and also the Therapeutic Gain (TG). To do this, the entire TRR structure including the reactor core, pool, the thermal column and beam tubes have been modeled using MCNPX Monte Carlo code. To measure in-phantom dose distribution a special head phantom has been constructed and foil activation techniques and TLD700 dosimeter have been used. The results show that there is enough uniformity in TRR thermal BNCT beam. TG parameter has the maximum value of 5.7 at the depth of 1 cm from the surface of the phantom, confirming that TRR thermal neutron beam has potential for being used in treatment of superficial brain tumors. For the purpose of a clinical trial, more modifications need to be done at the reactor, as, for example design, and construction of a treatment room at the beam exit which is our plan for future. To date, this beam is usable for biological studies and animal trials. There is a relatively good agreement between simulation and measurement especially within a diameter of 10 cm which is the dimension of usual BNCT beam ports. This relatively good agreement enables a more precise prediction of the irradiation conditions needed for future experiments.

  19. Simulation of n-qubit quantum systems. V. Quantum measurements

    NASA Astrophysics Data System (ADS)

    Radtke, T.; Fritzsche, S.

    2010-02-01

    The FEYNMAN program has been developed during the last years to support case studies on the dynamics and entanglement of n-qubit quantum registers. Apart from basic transformations and (gate) operations, it currently supports a good number of separability criteria and entanglement measures, quantum channels as well as the parametrizations of various frequently applied objects in quantum information theory, such as (pure and mixed) quantum states, hermitian and unitary matrices or classical probability distributions. With the present update of the FEYNMAN program, we provide a simple access to (the simulation of) quantum measurements. This includes not only the widely-applied projective measurements upon the eigenspaces of some given operator but also single-qubit measurements in various pre- and user-defined bases as well as the support for two-qubit Bell measurements. In addition, we help perform generalized and POVM measurements. Knowing the importance of measurements for many quantum information protocols, e.g., one-way computing, we hope that this update makes the FEYNMAN code an attractive and versatile tool for both, research and education. New version program summaryProgram title: FEYNMAN Catalogue identifier: ADWE_v5_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADWE_v5_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 27 210 No. of bytes in distributed program, including test data, etc.: 1 960 471 Distribution format: tar.gz Programming language: Maple 12 Computer: Any computer with Maple software installed Operating system: Any system that supports Maple; the program has been tested under Microsoft Windows XP and Linux Classification: 4.15 Catalogue identifier of previous version: ADWE_v4_0 Journal reference of previous version: Comput. Phys. Commun

  20. Measurement of cricoid pressure force during simulated Sellick's manoeuvre.

    PubMed

    Andruszkiewicz, Paweł; Zawadka, Mateusz; Kosińska, Anna; Walczak-Wieteska, Paulina; Majerowicz, Kalina

    2017-09-27

    Cricoid pressure is a standard anaesthetic procedure used to reduce the risk of aspiration of gastric contents during the induction of general anaesthesia. However, for several years its validity has been questioned. There still remains the question of whether we perform it correctly. The aim of the study was an evaluation of the theoretical knowledge of Sellick's manoeuvre, as well an assessment of practical skill related with it when simulated on a model of the upper airway. The study was performed on a cohort of anaesthetists and anaesthetic nurses working in various hospitals in the Warsaw area. Measurements were taken on an upper airway model placed on an electronic kitchen scale. Participants were asked to perform Sellick's manoeuvre in the way they do it in their clinical practice. The test was done twice. Both the position and pressures applied on the model were documented. Knowledge concerning current recommendations of cricoid force was noted. 206 subjects participated in the study. Only 49% (n = 101) properly identified cricoid cartilage during their application of Sellick's manoeuvre. Application of the correct pressure on the model of the airway was noted in 16.5% (n = 34) during the first attempt and in 20.4% (n = 42) during the second attempt. The median force applied during simulated Sellick's manoeuvrewas 36 N (IQR: 26-55) in the first attempt, and 38 (IQR 25-55) in the second attempt. Sellick's manoeuvre was performed incorrectly in many cases. Half of the participants of our study applied the pressure in the wrong place while the majority of them used an inappropriate amount of force. Thus, the application of cricoid pressure in patients should be preceded with simulation training.

  1. Measurement of time delay for a prospectively gated CT simulator

    PubMed Central

    Goharian, M.; Khan, R. F. H.

    2010-01-01

    For the management of mobile tumors, respiratory gating is the ideal option, both during imaging and during therapy. The major advantage of respiratory gating during imaging is that it is possible to create a single artifact-free CT data-set during a selected phase of the patient's breathing cycle. The purpose of the present work is to present a simple technique to measure the time delay during acquisition of a prospectively gated CT. The time delay of a Philips Brilliance BigBore™ (Philips Medical Systems, Madison, WI) scanner attached to a Varian Real-Time Position Management™ (RPM) system (Varian Medical Systems, Palo Alto, CA) was measured. Two methods were used to measure the CT time delay: using a motion phantom and using a recorded data file from the RPM system. In the first technique, a rotating wheel phantom was altered by placing two plastic balls on its axis and rim, respectively. For a desired gate, the relative positions of the balls were measured from the acquired CT data and converted into corresponding phases. Phase difference was calculated between the measured phases and the desired phases. Using period of motion, the phase difference was converted into time delay. The Varian RPM system provides an external breathing signal; it also records transistor-transistor logic (TTL) ‘X-Ray ON’ status signal from the CT scanner in a text file. The TTL ‘X-Ray ON’ indicates the start of CT image acquisition. Thus, knowledge of the start time of CT acquisition, combined with the real-time phase and amplitude data from the external respiratory signal, provides time-stamping of all images in an axial CT scan. The TTL signal with time-stamp was used to calculate when (during the breathing cycle) a slice was recorded. Using the two approaches, the time delay between the prospective gating signal and CT simulator has been determined to be 367 ± 40 ms. The delay requires corrections both at image acquisition and while setting gates for the treatment

  2. Measurements and simulations of focused beam for orthovoltage therapy

    SciTech Connect

    Abbas, Hassan; Mahato, Dip N.; Satti, Jahangir; MacDonald, C. A.

    2014-04-15

    Purpose: Megavoltage photon beams are typically used for therapy because of their skin-sparing effect. However, a focused low-energy x-ray beam would also be skin sparing, and would have a higher dose concentration at the focal spot. Such a beam can be produced with polycapillary optics. MCNP5 was used to model dose profiles for a scanned focused beam, using measured beam parameters. The potential of low energy focused x-ray beams for radiation therapy was assessed. Methods: A polycapillary optic was used to focus the x-ray beam from a tungsten source. The optic was characterized and measurements were performed at 50 kV. PMMA blocks of varying thicknesses were placed between optic and the focal spot to observe any variation in the focusing of the beam after passing through the tissue-equivalent material. The measured energy spectrum was used to model the focused beam in MCNP5. A source card (SDEF) in MCNP5 was used to simulate the converging x-ray beam. Dose calculations were performed inside a breast tissue phantom. Results: The measured focal spot size for the polycapillary optic was 0.2 mm with a depth of field of 5 mm. The measured focal spot remained unchanged through 40 mm of phantom thickness. The calculated depth dose curve inside the breast tissue showed a dose peak several centimeters below the skin with a sharp dose fall off around the focus. The percent dose falls below 10% within 5 mm of the focus. It was shown that rotating the optic during scanning would preserve the skin-sparing effect of the focused beam. Conclusions: Low energy focused x-ray beams could be used to irradiate tumors inside soft tissue within 5 cm of the surface.

  3. Measuring Renyi entanglement entropy in quantum Monte Carlo simulations.

    PubMed

    Hastings, Matthew B; González, Iván; Kallin, Ann B; Melko, Roger G

    2010-04-16

    We develop a quantum Monte Carlo procedure, in the valence bond basis, to measure the Renyi entanglement entropy of a many-body ground state as the expectation value of a unitary Swap operator acting on two copies of the system. An improved estimator involving the ratio of Swap operators for different subregions enables convergence of the entropy in a simulation time polynomial in the system size. We demonstrate convergence of the Renyi entropy to exact results for a Heisenberg chain. Finally, we calculate the scaling of the Renyi entropy in the two-dimensional Heisenberg model and confirm that the Néel ground state obeys the expected area law for systems up to linear size L=32.

  4. Measures Of Diffusion Regions Applied To PIC Reconnection Simulations

    NASA Astrophysics Data System (ADS)

    Goldman, M. V.; Newman, D. L.; Lapenta, G.

    2015-12-01

    The primary goal of the current NASA-MMS mission is to "identify and study diffusion regions during magnetic reconnection in Earth's magnetopause and magnetotail. Yet the term diffusion region is often misunderstood and can be ambiguous. Different conditions for a region to be a "diffusion region" are interpreted theoretically, related to each other and applied to PIC simulations of tail reconnection(a) (and to MMS measurements, if possible, at time of AGU). None of the conditions is both necessary and sufficient for topological reconnection to occur. During magnetic reconnection in a kinetic plasma key differences exist between the locations of diffusion regions in the electron fluid, the ion fluid and a single (MHD) fluid. (a)M.V. Goldman, D.L. Newman and G. Lapenta, Space Science Reviews, 2015

  5. Heat transfer measurements and CFD simulations of an impinging jet

    NASA Astrophysics Data System (ADS)

    Petera, Karel; Dostál, Martin

    2016-03-01

    Heat transport in impinging jets makes a part of many experimental and numerical studies because some similarities can be identified between a pure impingement jet and industrial processes like, for example, the heat transfer at the bottom of an agitated vessel. In this paper, experimental results based on measuring the response to heat flux oscillations applied to the heat transfer surface are compared with CFD simulations. The computational cost of a LES-based approach is usually too high therefore a comparison with less computationally expensive RANS-based turbulence models is made in this paper and a possible improvement of implementing an anisotropic explicit algebraic model for the turbulent heat flux model is evaluated.

  6. Aerodynamic measurements on a finite wing with simulated ice

    NASA Technical Reports Server (NTRS)

    Bragg, M. B.; Khodadoust, A.; Soltani, R.; Wells, S.; Kerho, M.

    1991-01-01

    The effect of a simulated glaze ice accretion on the aerodynamic performance of a three-dimensional straight and swept wing is studied experimentally. A semispan wing of effective aspect ratio five was mounted from the sidewall of the UIUC subsonic wind tunnel. The model uses an NACA 0012 airfoil section on a rectangular planform with interchangeable tip and root sections to allow for 0- and 30-deg sweep. A sidewall suction system is used to minimize the tunnel boundary-layer interaction with the model. A three-component sidewall balance has been designed, built and used to measure lift, drag and pitching moment on the clean and iced model. Fluorescent oil flow visualization has been performed on the iced model and reveals extensive spanwise flow in the separation bubble aft of the upper surface horn. These results are compared to computational results for the surface pressures, span loads and surface oil flow.

  7. Prognostic significance of blood pressure measured in the office, at home and during ambulatory monitoring in older patients in general practice.

    PubMed

    Fagard, R H; Van Den Broeke, C; De Cort, P

    2005-10-01

    The purpose of the study was to assess the prognostic significance of out-of-the-office blood pressure (BP) measurement in older patients in general practice, and to compare the results for BP measured in the office, at home and during 24-h ambulatory monitoring. All registerd patients who were 60 years or older were eligible for the study, except when bedridden, demented or admitted in a home for sick elderly people, or when they had suffered a myocardial infarction or stroke. After baseline measurements in 1990-1993, incidence of major cardiovascular events (cardiovascular death, myocardial infarction and stroke) was ascertained in 2002-2003 and related to the BPs by use of multivariate Cox regression analysis. Age of the 391 patients averaged 71+/-9 years; 40% were men. During median follow-up of 10.9 years, 86 patients (22%) suffered a cardiovascular event. The adjusted relative hazard rate, associated with a 1 s.d. increment in systolic BP was 1.13 for office BP (NS), and, respectively, 1.32, 1.33 and 1.42, for home, daytime and night time BP (P< or =0.01 for all). Results were similar for diastolic BP. The prognostic significance of all out-of-the-office BPs was independent of office BP. The prognostic value of home BP was equal to (systolic) or even better (diastolic) than that of daytime BP. Night time BP predicted cardiovascular events independent of all other BPs. Prognosis of white-coat hypertension was similar to that of true normotension, but better than in sustained hypertension. In conclusion, the prognostic value of home BP is better than that of office BP in older patients in primary care, and is at least equal to that of daytime ambulatory BP. The prognosis of patients with white-coat hypertension is similar to that of true normotensives.

  8. OPERATION SUN BEAM, SHOT SMALL BOY. Project Officer’s Report - Project 7.1.4. Transient Radiation Effects Measurements on Guidance System Circuits

    DTIC Science & Technology

    1985-09-01

    BEAM, SHOT SMALL BOY Project Officer’s Report—Project 7.1.4 00 oo in en < i Q < CJ> Transient Radiation Effects Measurements on Guidance...This is an extract of P0R-2239 (WT-2239), Operation SUN BEAM. Shot Small Boy. Project 7.1.4. Approved for public release; distribution is unlimited...UNIT ACCESSION NO ; ■ ■ i ./nc/uc/e sr.unty c/.m.f/Mf.ofijOPERATION SUN BEAM, SHOT SMALL BOY, Project Officer’s Report- Project 7.1.4, Transient

  9. Observing System Simulations for ASCENDS: Synthesizing Science Measurement Requirements (Invited)

    NASA Astrophysics Data System (ADS)

    Kawa, S. R.; Baker, D. F.; Schuh, A. E.; Crowell, S.; Rayner, P. J.; Hammerling, D.; Michalak, A. M.; Wang, J. S.; Eluszkiewicz, J.; Ott, L.; Zaccheo, T.; Abshire, J. B.; Browell, E. V.; Moore, B.; Crisp, D.

    2013-12-01

    The measurement of atmospheric CO2 from space using active (lidar) sensing techniques has several potentially significant advantages in comparison to current and planned passive CO2 instruments. Application of this new technology aims to advance CO2 measurement capability and carbon cycle science into the next decade. The NASA Active Sensing of Carbon Emissions, Nights, Days, and Seasons (ASCENDS) mission has been recommended by the US National Academy of Sciences Decadal Survey for the next generation of space-based CO2 observing systems. ASCENDS is currently planned for launch in 2022. Several possible lidar instrument approaches have been demonstrated in airborne campaigns and the results indicate that such sensors are quite feasible. Studies are now underway to evaluate performance requirements for space mission implementation. Satellite CO2 observations must be highly precise and unbiased in order to accurately infer global carbon source/sink fluxes. Measurement demands are likely to further increase in the wake of GOSAT, OCO-2, and enhanced ground-based in situ and remote sensing CO2 data. The objective of our work is to quantitatively and consistently evaluate the measurement capabilities and requirements for ASCENDS in the context of advancing our knowledge of carbon flux distributions and their dependence on underlying physical processes. Considerations include requirements for precision, relative accuracy, spatial/temporal coverage and resolution, vertical information content, interferences, and possibly the tradeoffs among these parameters, while at the same time framing a mission that can be implemented within a constrained budget. Here, we attempt to synthesize the results of observing system simulation studies, commissioned by the ASCENDS Science Requirements Definition Team, into a coherent set of mission performance guidelines. A variety of forward and inverse model frameworks are employed to reduce the potential dependence of the results on model

  10. An assessment of discriminatory power of office blood pressure measurements in predicting optimal ambulatory blood pressure control in people with type 2 diabetes

    PubMed Central

    Kengne, Andre Pascal; Libend, Christelle Nong; Dzudie, Anastase; Menanga, Alain; Dehayem, Mesmin Yefou; Kingue, Samuel; Sobngwi, Eugene

    2014-01-01

    Introduction Ambulatory blood pressure (BP) measurements (ABPM) predict health outcomes better than office BP, and are recommended for assessing BP control, particularly in high-risk patients. We assessed the performance of office BP in predicting optimal ambulatory BP control in sub-Saharan Africans with type 2 diabetes (T2DM). Methods Participants were a random sample of 51 T2DM patients (25 men) drug-treated for hypertension, receiving care in a referral diabetes clinic in Yaounde, Cameroon. A quality control group included 46 non-diabetic individuals with hypertension. Targets for BP control were systolic (and diastolic) BP. Results Mean age of diabetic participants was 60 years (standard deviation: 10) and median duration of diabetes was 6 years (min-max: 0-29). Correlation coefficients between each office-based variable and the 24-h ABPM equivalent (diabetic vs. non-diabetic participants) were 0.571 and 0.601 for systolic (SBP), 0.520 and 0.539 for diastolic (DBP), 0.631 and 0.549 for pulse pressure (PP), and 0.522 and 0.583 for mean arterial pressure (MAP). The c-statistic for the prediction of optimal ambulatory control from office-BP in diabetic participants was 0.717 for SBP, 0.494 for DBP, 0.712 for PP, 0.582 for MAP, and 0.721 for either SBP + DBP or PP + MAP. Equivalents in diabetes-free participants were 0.805, 0.763, 0.695, 0.801 and 0.813. Conclusion Office DBP was ineffective in discriminating optimal ambulatory BP control in diabetic patients, and did not improve predictions based on office SBP alone. Targeting ABPM to those T2DM patients who are already at optimal office-based SBP would likely be more cost effective in this setting. PMID:25838859

  11. Electrophysiological measurement of interest during walking in a simulated environment.

    PubMed

    Takeda, Yuji; Okuma, Takashi; Kimura, Motohiro; Kurata, Takeshi; Takenaka, Takeshi; Iwaki, Sunao

    2014-09-01

    A reliable neuroscientific technique for objectively estimating the degree of interest in a real environment is currently required in the research fields of neuroergonomics and neuroeconomics. Toward the development of such a technique, the present study explored electrophysiological measures that reflect an observer's interest in a nearly-real visual environment. Participants were asked to walk through a simulated shopping mall and the attractiveness of the shopping mall was manipulated by opening and closing the shutters of stores. During the walking task, participants were exposed to task-irrelevant auditory probes (two-stimulus oddball sequence). The results showed a smaller P2/early P3a component of task-irrelevant auditory event-related potentials and a larger lambda response of eye-fixation-related potentials in an interesting environment (i.e., open-shutter condition) than in a boring environment (i.e., closed-shutter condition); these findings can be reasonably explained by supposing that participants allocated more attentional resources to visual information in an interesting environment than in a boring environment, and thus residual attentional resources that could be allocated to task-irrelevant auditory probes were reduced. The P2/early P3a component and the lambda response may be useful measures of interest in a real visual environment. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Development of a model for the simulation of Farinograph measurements

    NASA Astrophysics Data System (ADS)

    Hermannseder, Bernhard; Ahmad, Muhammad Haseeb; Kügler, Philip; Hitzmann, Bernd

    2016-10-01

    Based upon kneading curves obtained from eight wheat flours using different cultivars, a mathematical model was developed to simulate the middle curve of Farinograph measurements. In the model the different states of the protein polymers during the kneading process are considered. All together five different states of protein polymer fractions are presumed: 1. non-hydrated, 2. unstretched, 3. stretched, 4. intermediate and 5. broken protein polymer fraction, which are represented by their corresponding state variables. The model consists of five connected ordinary differential equations with first and second order kinetics, which describe the dynamic behavior of the state variables using four kinetic parameters. Four state variables are used in a weighted sum (four parameters) to calculate the Farinograph middle curve. Using the dynamic process model the eight different Farinograph measurements are fitted individually by eight parameters in total. The system of differential equations was solved with an implicit finite difference method. Each step of the fit was done by a Quasi-Newton method. The overall fits were very good, with an average R2 of 0.996 ± 0.003 and an average sum of squared errors of 5,000 ± 3,000 BU2.

  13. Simulations & Measurements of Airframe Noise: A BANC Workshops Perspective

    NASA Technical Reports Server (NTRS)

    Choudhari, Meelan; Lockard, David

    2016-01-01

    Airframe noise corresponds to the acoustic radiation due to turbulent flow in the vicinity of airframe components such as high-lift devices and landing gears. Since 2010, the American Institute of Aeronautics and Astronautics has organized an ongoing series of workshops devoted to Benchmark Problems for Airframe Noise Computations (BANC). The BANC workshops are aimed at enabling a systematic progress in the understanding and high-fidelity predictions of airframe noise via collaborative investigations that integrate computational fluid dynamics, computational aeroacoustics, and in depth measurements targeting a selected set of canonical yet realistic configurations that advance the current state-of-the-art in multiple respects. Unique features of the BANC Workshops include: intrinsically multi-disciplinary focus involving both fluid dynamics and aeroacoustics, holistic rather than predictive emphasis, concurrent, long term evolution of experiments and simulations with a powerful interplay between the two, and strongly integrative nature by virtue of multi-team, multi-facility, multiple-entry measurements. This paper illustrates these features in the context of the BANC problem categories and outlines some of the challenges involved and how they were addressed. A brief summary of the BANC effort, including its technical objectives, strategy, and selective outcomes thus far is also included.

  14. Simulated O VI Doppler dimming measurements of coronal outflow velocities

    NASA Technical Reports Server (NTRS)

    Strachan, Leonard; Gardner, L. D.; Kohl, John L.

    1992-01-01

    The possibility of determining O(5+) outflow velocities by using a Doppler dimming analysis of the resonantly scattered intensities of O VI lambda 1031.9 and lambda 1037.6 is addressed. The technique is sensitive to outflow velocities, W, in the range W greater than 30 and less than 250 km/s and can be used for probing regions of the inner solar corona, where significant coronal heating and solar wind acceleration may be occurring. These velocity measurements, when combined with measurements of other plasma parameters (temperatures and densities of ions and electrons) can be used to estimate the energy and mass flux of O(5+). In particular, it may be possible to locate where the flow changes from subsonic to supersonic and to identify source regions for the high and low speed solar wind. The velocity diagnostic technique is discussed with emphasis placed on the requirements needed for accurate outflow velocity determinations. Model determinations of outflow velocities based on simulated Doppler observations are presented.

  15. Spectral Irradiance Measurements of Simulated Lightning in Planetary Atmospheres

    NASA Technical Reports Server (NTRS)

    Borucki, W. J.; McKay, C. P.; Jebbens, D.; Lakkaraju, H. S.; Vanajakshi, C. T.; Cuzzi, Jeffrey (Technical Monitor)

    1996-01-01

    Optical emissions from lightning provide information to estimate the altitude, latitude and longitude of lightning storms, the energy of the discharges, and the production of important trace species such as HCN and C2H2. Knowledge of the spectra of planetary lightning is needed to deduce the total energy dissipated by lightning (and thereby, the production of trace gases) and to help design experiments to detect and track lightning storms. Measurements of the spectral irradiance from approximately 380 to 820 nm are reported for laboratory simulations of lightning in the atmospheres of Venus, Jupiter, and Titan. In our laboratory, laser-induced plasmas (LIP) are used to simulate lightning discharges. This technique avoids contamination of the spectra by elect-ode material and maintains a safe environment while allowing the use of flammable gases, such as hydrogen and methane, found in outer planet atmospheres. The observations were made at I and 5 bars pressure for Venus and Jupiter and at 1 bar for the Titan mixture. At a pressure of one bar, our results show prominent lines from H(sub alpha), H(sub beta), H(sub gamma), and H(sub delta) lines of the Balmer Series of atomic hydrogen, a single line from Helium at 588 nm and strong continuum radiation. At pressures of 5 bars, the H(sub alpha) and H(sub beta) lines are wider, the H(sub gamma), and H(sub delta) lines merge into the continuum because of pressure broadening, and the helium line at 588 nm is no longer visible. The observed spectra of simulated lightning in the venusian atmosphere at 1 and 5 bars shows that the OI multiplet at 777.7 nm dominates the spectra, but weak features due to atomic carbon and singly excited and singly ionized oxygen atoms are also visible. Although lightning has not yet been observed on Titan, it conceivable that some form of lightning discharge could be occurring. Therefore experiments on a Titan atmosphere mixture were conducted. The most prominent features seen in the simulated

  16. Study of accuracy of precipitation measurements using simulation method

    NASA Astrophysics Data System (ADS)

    Nagy, Zoltán; Lajos, Tamás; Morvai, Krisztián

    2013-04-01

    Hungarian Meteorological Service1 Budapest University of Technology and Economics2 Precipitation is one of the the most important meteorological parameters describing the state of the climate and to get correct information from trends, accurate measurements of precipitation is very important. The problem is that the precipitation measurements are affected by systematic errors leading to an underestimation of actual precipitation which errors vary by type of precipitaion and gauge type. It is well known that the wind speed is the most important enviromental factor that contributes to the underestimation of actual precipitation, especially for solid precipitation. To study and correct the errors of precipitation measurements there are two basic possibilities: · Use of results and conclusion of International Precipitation Measurements Intercomparisons; · To build standard reference gauges (DFIR, pit gauge) and make own investigation; In 1999 at the HMS we tried to achieve own investigation and built standard reference gauges But the cost-benefit ratio in case of snow (use of DFIR) was very bad (we had several winters without significant amount of snow, while the state of DFIR was continously falling) Due to the problem mentioned above there was need for new approximation that was the modelling made by Budapest University of Technology and Economics, Department of Fluid Mechanics using the FLUENT 6.2 model. The ANSYS Fluent package is featured fluid dynamics solution for modelling flow and other related physical phenomena. It provides the tools needed to describe atmospheric processes, design and optimize new equipment. The CFD package includes solvers that accurately simulate behaviour of the broad range of flows that from single-phase to multi-phase. The questions we wanted to get answer to are as follows: · How do the different types of gauges deform the airflow around themselves? · Try to give quantitative estimation of wind induced error. · How does the use

  17. Measuring aniseikonia using scattering filters to simulate cataract

    NASA Astrophysics Data System (ADS)

    Wilson, Jason

    2011-12-01

    The relationship between anisometropia and aniseikonia (ANK) is not well understood. Ametropic cataract patients provide a unique opportunity to study this relationship after undergoing emmetropizing lens extraction. Because light scatter may affect ANK measurement in cataract patients, its effect should also be evaluated. The Basic Aniseikonia Test (BAT) was evaluated using afocal size lenses to produce specific changes in retinal height. Several light scattering devices were then evaluated to determine which produced effects most similar to cataract. Contrast sensitivity and visual acuity (VA) losses were measured with each device and compared to those reported in cataract. After determining the most appropriate light scattering device, twenty healthy patients with normal visual function were recruited to perform the BAT using the filters to simulate cataract. Cataract patients were recruited from Vision America and the University of Alabama at Birmingham School of Optometry. Patients between 20 and 75 years of age with at least 20/80 VA in each eye, ≥ 2D ametropia, and normal binocular function were recruited. Stereopsis and ANK were tested and each patient completed a symptom questionnaire. ANK measurements using afocal size lenses indicated that the BAT underestimates ANK, although the effect was minimal for vertical targets and darkened surroundings, as previously reported. Based on VA and contrast sensitivity loss, Vistech scattering filters produced changes most similar to cataract. Results of the BAT using Vistech filters demonstrated that a moderate cataract but not a mild cataract may affect the ANK measurement. ANK measurements on cataract patients indicated that those with ≥ 2 D ametropia in each eye may suffer from induced ANK after the first cataract extraction. With upcoming healthcare reform, unilateral cataract extraction may be covered, but not necessarily bilateral, depending on patient VA in each eye. However, a questionnaire about symptoms

  18. Student measurement of blood pressure using a simulator arm compared with a live subject's arm.

    PubMed

    Lee, Jennifer J; Sobieraj, Diana M; Kuti, Effie L

    2010-06-15

    To compare accuracy of blood pressure measurements using a live subject and a simulator arm, and to determine students' preferences regarding measurement. This was a crossover study comparing blood pressure measurements from a live subject and a simulator arm. Students completed an anonymous survey instrument defining opinions on ease of measurement. Fifty-seven students completed blood pressure measurements on live subjects while 72 students completed blood pressure measurements using the simulator arm. There were no significant systematic differences between the 2 measurement techniques. Systolic blood pressure measurements from a live subject arm were less likely to be within 4 mm Hg compared with measurements of a simulator arm. Diastolic blood pressure measurements were not significantly different between the 2 techniques. Accuracy of student measurement of blood pressure using a simulator arm was similar to the accuracy with a live subject. There was no difference in students' preferences regarding measurement techniques.

  19. Using GTO-Velo to Facilitate Communication and Sharing of Simulation Results in Support of the Geothermal Technologies Office Code Comparison Study

    SciTech Connect

    White, Signe K.; Purohit, Sumit; Boyd, Lauren W.

    2015-01-26

    The Geothermal Technologies Office Code Comparison Study (GTO-CCS) aims to support the DOE Geothermal Technologies Office in organizing and executing a model comparison activity. This project is directed at testing, diagnosing differences, and demonstrating modeling capabilities of a worldwide collection of numerical simulators for evaluating geothermal technologies. Teams of researchers are collaborating in this code comparison effort, and it is important to be able to share results in a forum where technical discussions can easily take place without requiring teams to travel to a common location. Pacific Northwest National Laboratory has developed an open-source, flexible framework called Velo that provides a knowledge management infrastructure and tools to support modeling and simulation for a variety of types of projects in a number of scientific domains. GTO-Velo is a customized version of the Velo Framework that is being used as the collaborative tool in support of the GTO-CCS project. Velo is designed around a novel integration of a collaborative Web-based environment and a scalable enterprise Content Management System (CMS). The underlying framework provides a flexible and unstructured data storage system that allows for easy upload of files that can be in any format. Data files are organized in hierarchical folders and each folder and each file has a corresponding wiki page for metadata. The user interacts with Velo through a web browser based wiki technology, providing the benefit of familiarity and ease of use. High-level folders have been defined in GTO-Velo for the benchmark problem descriptions, descriptions of simulator/code capabilities, a project notebook, and folders for participating teams. Each team has a subfolder with write access limited only to the team members, where they can upload their simulation results. The GTO-CCS participants are charged with defining the benchmark problems for the study, and as each GTO-CCS Benchmark problem is

  20. Comparison of the simulated performance of a VSAT satellite link with measurements

    NASA Astrophysics Data System (ADS)

    Mwanakatwe, M.; Willis, M. J.; Evans, B. G.

    1991-06-01

    The transmisson performance of a Ka-band VSAT system (CODE) has been simulated to verify the systems design and to demonstrate the adequacy of the implementation margin and phase noise. A detailed simulation of phase noise effects on VSAT systems design is also presented. Hardware measurements and BOSS simulations for the test set-up show a good agreement for values of Eb/N0 up to 7dB. The simulated results indicate an increased error when the TWTA is operated in the nonlinear region, with the simulations indicating larger degradation than the measurement. The phase noise performance of the digital TRL modem is found to be consistently better than that of the simulated model. There appears to be closer agreement with the BOSS simulations than with the TOPSIM III simulations. The discrepancy between the TOPSIM III and BOSS phase noise simulations was only resolved by measurements taken using the Olympus satellite and BTI satellite simulator.

  1. Measurements and large eddy simulation of propagating premixed flames

    SciTech Connect

    Masri, A.R.; Cadwallader, B.J.; Ibrahim, S.S.

    2006-07-15

    This paper presents an experimental and numerical study of unsteady turbulent premixed flames igniting in an initially stagnant mixture and propagating past solid obstacles. The objective here is to study the outstanding issue of flow-flame interactions in transient premixed combustion environments. Particular emphasis is placed on the burning rate and the structure of the flame front. The experimental configuration consists of a chamber with a square cross-section filled with a combustible mixture of propane-air ignited from rest. An array of baffle plates as well as geometrical obstructions of varying shapes and blockage ratios, are placed in the path of the flame as it propagates from the ignition source to the vented end of the enclosure. A range of flame propagation conditions are studied experimentally. Measurements are presented for pressure-time traces, high-speed images of the flame front, mean velocities obtained from particle imaging velocimetry and laser induced fluorescence images of the hydroxyl radical OH. Three-dimensional large eddy simulations (LES) are also made for a case where a square obstacle and an array of baffle plates are placed in the chamber. The dynamic Germano model and a simple flamelet combustion model are used at the sub-grid scale. The effects of grid size and sub-grid filter width are also discussed. Calculations and measurements are found to be in good agreement with respect to flame structure and peak overpressure. Turbulence levels increase significantly at the leading edge of the flame as it propagates past the array of baffle plates and the obstacle. With reference to the regime diagrams for turbulent premixed combustion, it is noted that the flame continues to lie in the zones of thin reactions or corrugated flamelets regardless of the stage of propagation along the chamber. (author)

  2. Measurements of the Ionization Coefficient of Simulated Iron Micrometeoroids

    NASA Technical Reports Server (NTRS)

    Thomas, Evan; Horanyi, Mihaly; Janches, Diego; Munsat, Tobin; Simolka, Jonas; Sternovsky, Zoltan

    2016-01-01

    The interpretation of meteor radar observations has remained an open problem for decades. One of the most critical parameters to establish the size of an incoming meteoroid from radar echoes is the ionization coefficient, beta, which still remains poorly known. Here we report on new experiments to simulate micrometeoroid ablation in laboratory conditions to measure beta for iron particles impacting N2, air,CO2, and He gases. This new data set is compared to previous laboratory data where we find agreement except for He and air impacts greater than 30 kms. We calibrate the Jones model of beta(v) and provide fit parameters to these gases and find agreement with all gases except CO2 and high-speed air impacts where we observe beta(sub air) greater than 1 for velocities greater than 70 kms. These data therefore demonstrate potential problems with using the Jones model for CO2 atmospheres as well as for high-speed meteors on Earth.

  3. Measurement of impact force, simulation of fall and hip fracture.

    PubMed

    Gardner, T N; Simpson, A H; Booth, C; Sprukkelhorst, P; Evans, M; Kenwright, J; Evans, J G

    1998-01-01

    It has been shown that the incidence of hip fracture in the elderly may be influenced by the type of floor covering commonly used in homes for the elderly. This study describes the development of a method for modelling a fall during a hip fracture event, to examine the influence of different floors on impact force. An impact transducer is dropped in free fall through a smooth plastic tube. The impactor nose of the transducer models the curvature of the greater trochanter, and a steel spring is used to simulate the compliance of the skeletal structure. A weight, which corresponds to one-sixteenth of average body mass, compresses the spring and applies force to the impactor nose on striking the floor. The temporal variation in the force of impact with the floor is measured by the transducer to within 0.41 percent (SD = 0.63%, n = 10). Five common floor coverings were tested over a concrete floor slab (vinyl, loop carpet and pile carpet--both with and without underpad). ANOVA analysis showed that the differences between mean forces for each floor covering were highly significant (p > 0.001), with the thicker coverings producing 7 percent lower forces. The transducer may be used to examine the correlation between impact force and fracture incidence for a variety of different floors in homes for the elderly.

  4. HOMs simulation and measurement results of IHEP02 cavity

    NASA Astrophysics Data System (ADS)

    Zheng, Hong-Juan; Zhai, Ji-Yuan; Zhao, Tong-Xian; Gao, Jie

    2015-11-01

    In accelerator RF cavities, there exists not only the fundamental mode which is used to accelerate the beam, but also higher order modes (HOMs). The higher order modes excited by the beam can seriously affect beam quality, especially for the higher R/Q modes. 1.3 GHz low-loss 9-cell superconducting cavity as a candidate for ILC high gradient cavity, the properties of higher order mode has not been studied carefully. IHEP based on existing low loss cavity, designed and developed a large grain size 1.3 GHz low-loss 9-cell superconducting cavity (IHEP02 cavity). The higher order mode coupler of IHEP02 used TESLA coupler's design. As a result of the limitation of the mechanical design, the distance between higher order mode coupler and end cell is larger than TESLA cavity. This paper reports on measured results of higher order modes in the IHEP02 1.3 GHz low-loss 9-cell superconducting cavity. Using different methods, Qe of the dangerous modes passbands have been obtained. The results are compared with TESLA cavity results. R/Q of the first three passbands have also been obtained by simulation and compared with the results of the TESLA cavity. Supported by Knowledge Innovation Project of The Chinese Academy of Sciences

  5. New simulation and measurement results on gateable DEPFET devices

    NASA Astrophysics Data System (ADS)

    Bähr, Alexander; Aschauer, Stefan; Hermenau, Katrin; Herrmann, Sven; Lechner, Peter H.; Lutz, Gerhard; Majewski, Petra; Miessner, Danilo; Porro, Matteo; Richter, Rainer H.; Schaller, Gerhard; Sandow, Christian; Schnecke, Martina; Schopper, Florian; Stefanescu, Alexander; Strüder, Lothar; Treis, Johannes

    2012-07-01

    To improve the signal to noise level, devices for optical and x-ray astronomy use techniques to suppress background events. Well known examples are e.g. shutters or frame-store Charge Coupled Devices (CCDs). Based on the DEpleted P-channel Field Effect Transistor (DEPFET) principle a so-called Gatebale DEPFET detector can be built. Those devices combine the DEPFET principle with a fast built-in electronic shutter usable for optical and x-ray applications. The DEPFET itself is the basic cell of an active pixel sensor build on a fully depleted bulk. It combines internal amplification, readout on demand, analog storage of the signal charge and a low readout noise with full sensitivity over the whole bulk thickness. A Gatebale DEPFET has all these benefits and obviates the need for an external shutter. Two concepts of Gatebale DEPFET layouts providing a built-in shutter will be introduced. Furthermore proof of principle measurements for both concepts are presented. Using recently produced prototypes a shielding of the collection anode up to 1 • 10-4 was achieved. Predicted by simulations, an optimized geometry should result in values of 1 • 10-5 and better. With the switching electronic currently in use a timing evaluation of the shutter opening and closing resulted in rise and fall times of 100ns.

  6. Simultaneous measurement of friction and wear in hip simulators.

    PubMed

    Haider, Hani; Weisenburger, Joel N; Garvin, Kevin L

    2016-05-01

    We propose and have evaluated a method to measure hip friction during wear testing on a popular multi-station hip simulator. A 6-degree-of-freedom load cell underneath the specimen sensed forces and torques during implant wear testing of simulated walking. This included internal-external and adduction-abduction rotations which are often neglected during friction testing on pendulum-type machines. Robust mathematical analysis and data processing provided friction estimates in three simultaneous orthogonal rotations, over extended multi-million cycle wear tests. We tested various bearing couples including metal-on-plastic, ceramic-on-plastic, and metal-on-metal material couples. In one test series, new and intentionally scratched CoCrMo 40-mm-diameter femoral heads were tested against conventional ultrahigh-molecular-weight polyethylene, highly cross-linked, and highly cross-linked with vitamin E versions. The scratching significantly increased friction and doubled the wear of all groups. Before scratching, friction levels for the aforementioned plastic groups were 0.056 ± 0.0060, 0.062 ± 0.0080, and 0.070 ± 0.0045, respectively, but after scratching increased to 0.088 ± 0.018, 0.076 ± 0.0066, and 0.082 ± 0.0049, respectively, all statistically significant increases (p = 0.00059, 0.00005, 0.0115, respectively). In another test series of 44-mm femoral head diameter hips, metal-on-plastic hips with conventional ultrahigh-molecular-weight polyethylene showed the lowest friction at 0.045 ± 0.0085, followed by highly cross-linked with 0.046 ± 0.0035 (not significantly different). In a ceramic-on-plastic design with conventional ultrahigh-molecular-weight polyethylene, higher friction 0.079 ± 0.0070 was measured likely due to that ceramic surface being rougher than usual. Metal-on-metal hips were compared without and with a TiN coating, resulting in 0.049 ± 0.014 and 0.097 ± 0.020 friction factors, respectively

  7. Simulation and Analysis of Cosmic Microwave Background Anisotropy Measurements

    NASA Astrophysics Data System (ADS)

    Delabrouille, Jacques H.

    This thesis work is devoted to the analysis of optimal methods allowing the reprojection of the data streams obtained by next-generation experiments for CMB mapping (and in particular the European space mission Planck Surveyor) onto two-dimensional maps free of instrument-induced artifacts. After a short introduction to the field of CMB anisotropy measurements, I calculate in Chapter 2 the cosmological signal expected on a circular scan as a function of the two dimensional anisotropy spectrum. This allows a comparison of the noise and signal spectra, and permits the optimization of several instrumental parameters. In addition to being useful for the optimized design of future CMB missions, this analysis is useful for Planck data reduction. Chapter 3 is dedicated to the modeling of the measurement of CMB anisotropies with the Planck High Frequency Instrument (HFI), and serves as an introduction to the next two chapters, which deal with two specific instrumental effects. The first is that of the presence of low-frequency drifts in the data streams, which can generate striping on the maps. In answer to the suggestion that the observing strategy of Planck might induce such an effect, I show in Chapter 4, with the help of numerical simulations and analytic calculations, that the low-frequency drifts can be corrected for. The constraints implied on the payload are easily satisfied. The second, which I address in Chapter 5, is the problem of straylight in the far sidelobes of the antenna pattern of Planck. Because of the high sensitivity goals, the rejection of the signals from the Sun, the Earth and the Galaxy below the noise level put stringent requirements on the payload, which are very difficult to fulfill. I show how an adequate processing of the data can lead to the identification of the signals from various sources, and to the subtraction of unwanted contributions from the signal. The last part of this work (Chapter 6) is devoted to the DIABOLO experiment and to

  8. Comparison of blood pressure measurements using an automated blood pressure device in community pharmacies and family physicians' offices: a randomized controlled trial.

    PubMed

    Chambers, Larry W; Kaczorowski, Janusz; O'Rielly, Susan; Ignagni, Sandra; Hearps, Stephen J C

    2013-01-01

    Accurate measurement of blood pressure is the foundation of appropriate diagnosis, treatment and ongoing management of hypertension. The use of automated blood pressure devices in community settings such as pharmacies provide opportunities for additional blood pressure measurement; however, it is important to ensure that these measurements are comparable to those taken in physicians' offices using the same devices. We conducted a randomized controlled trial to assess whether blood pressure readings assessed by use of an automated device differed according to the setting, specifically in community pharmacies and family physicians' offices. We included adults aged 65 years and older who did not live in long-term care facilities or in hospital. The trial was administered by volunteer peer health educators, family physicians and pharmacists in 2 midsized communities in Ontario from April to September 2010. The 5 participating family physicians mailed invitations to their eligible patients. Those who gave informed consent were randomly allocated to 1 of 2 assessment sequences: group A had their blood pressure measured at their physician's office, then at a pharmacy, then again at their physician's office; those in group B had their blood pressure measured at a pharmacy, then at their physician's office, then again at a pharmacy. An automated blood pressure device (BpTRU) was used in both settings. We calculated the differences in mean systolic and diastolic blood pressure, and we compared the readings at both settings and by sequence of assessment. In total, 275 adults completed the trial (mean age 75.9 yr, 49.5% male, 46.9% with a self-reported diagnosis of hypertension). There were no statistically significant differences in systolic or diastolic blood pressure measurements associated with the sequence of assessment or the setting. There was a significant difference in the overall mean systolic blood pressure between the 2 assessment sequences (group A 122.0 v. group

  9. Comparison of blood pressure measurements using an automated blood pressure device in community pharmacies and family physicians’ offices: a randomized controlled trial

    PubMed Central

    Kaczorowski, Janusz; O’Rielly, Susan; Ignagni, Sandra; Hearps, Stephen J.C.

    2013-01-01

    Background Accurate measurement of blood pressure is the foundation of appropriate diagnosis, treatment and ongoing management of hypertension. The use of automated blood pressure devices in community settings such as pharmacies provide opportunities for additional blood pressure measurement; however, it is important to ensure that these measurements are comparable to those taken in physicians’ offices using the same devices. We conducted a randomized controlled trial to assess whether blood pressure readings assessed by use of an automated device differed according to the setting, specifically in community pharmacies and family physicians’ offices. Methods We included adults aged 65 years and older who did not live in long-term care facilities or in hospital. The trial was administered by volunteer peer health educators, family physicians and pharmacists in 2 midsized communities in Ontario from April to September 2010. The 5 participating family physicians mailed invitations to their eligible patients. Those who gave informed consent were randomly allocated to 1 of 2 assessment sequences: group A had their blood pressure measured at their physician’s office, then at a pharmacy, then again at their physician’s office; those in group B had their blood pressure measured at a pharmacy, then at their physician’s office, then again at a pharmacy. An automated blood pressure device (BpTRU) was used in both settings. We calculated the differences in mean systolic and diastolic blood pressure, and we compared the readings at both settings and by sequence of assessment. Results In total, 275 adults completed the trial (mean age 75.9 yr, 49.5% male, 46.9% with a self-reported diagnosis of hypertension). There were no statistically significant differences in systolic or diastolic blood pressure measurements associated with the sequence of assessment or the setting. There was a significant difference in the overall mean systolic blood pressure between the 2

  10. Modeling, Simulation and Analysis of Complex Networked Systems: A Program Plan for DOE Office of Advanced Scientific Computing Research

    SciTech Connect

    Brown, D L

    2009-05-01

    Many complex systems of importance to the U.S. Department of Energy consist of networks of discrete components. Examples are cyber networks, such as the internet and local area networks over which nearly all DOE scientific, technical and administrative data must travel, the electric power grid, social networks whose behavior can drive energy demand, and biological networks such as genetic regulatory networks and metabolic networks. In spite of the importance of these complex networked systems to all aspects of DOE's operations, the scientific basis for understanding these systems lags seriously behind the strong foundations that exist for the 'physically-based' systems usually associated with DOE research programs that focus on such areas as climate modeling, fusion energy, high-energy and nuclear physics, nano-science, combustion, and astrophysics. DOE has a clear opportunity to develop a similarly strong scientific basis for understanding the structure and dynamics of networked systems by supporting a strong basic research program in this area. Such knowledge will provide a broad basis for, e.g., understanding and quantifying the efficacy of new security approaches for computer networks, improving the design of computer or communication networks to be more robust against failures or attacks, detecting potential catastrophic failure on the power grid and preventing or mitigating its effects, understanding how populations will respond to the availability of new energy sources or changes in energy policy, and detecting subtle vulnerabilities in large software systems to intentional attack. This white paper outlines plans for an aggressive new research program designed to accelerate the advancement of the scientific basis for complex networked systems of importance to the DOE. It will focus principally on four research areas: (1) understanding network structure, (2) understanding network dynamics, (3) predictive modeling and simulation for complex networked systems

  11. Experimental ship fire measurements with simulated radioactive cargo

    SciTech Connect

    Koski, J.A.; Arviso, M.; Bobbe, J.G.; Wix, S.D.; Cole, J.K.; Hohnstreiter, G.F.; Beene, D.E. Jr.; Keane, M.P.

    1997-10-01

    Results from a series of eight test fires ranging in size from 2.2 to 18.8 MW conducted aboard the Coast Guard fire test ship Mayo Lykes at Mobile, Alabama are presented and discussed. Tests aboard the break bulk type cargo ship consisted of heptane spray fires simulating engine room and galley fires, wood crib fires simulating cargo hold fires, and pool fires staged for comparison to land based regulatory fire results. Primary instrumentation for the tests consisted of two pipe calorimeters that simulated a typical package shape for radioactive materials packages.

  12. Measurement of Ground Level Muon Charge Ratio Using ECRS Simulation

    NASA Astrophysics Data System (ADS)

    Sanjeewa, Hakmana; He, Xiaochun; Cleven, Christopher

    2006-11-01

    The Muon charge ratio at the Earth's surface has been studied with a Geant4 based simulation for two different geomagnetic locations: Atlanta and Lynn Lake. The simulation results are shown in excellent agreement with the data from NMSU-WIZARD/CAPRICE and BESS experiments at Lynn Lake, At low momentum, ground level muon charge ratios show latitude dependent geomagnetic effects for both Atlanta and Lynn Lake from the simulation. The simulated charge ratio is 1.20 ± 0.05 (without geomagnetic field), 1.12 ± 0.05 (with geomagnetic field) for Atlanta and 1.22 ± 0.04 (with geomagnetic field) for Lynn Lake. These types of studies are very important for analyzing secondary cosmic ray muon flux distribution at Earth's surface and can be used to evaluate the parameter of atmospheric neutrino oscillations.

  13. Comparison of Hydrocode Simulations with Measured Shock Wave Velocities

    SciTech Connect

    Hixson, R. S.; Veeser, L. R.

    2014-11-30

    We have conducted detailed 1- and 2-dimensional hydrodynamics calculations to assess the quality of simulations commonly made to understand various shock processes in a sample and to design shock experiments. We began with relatively simple shock experiments, where we examined the effects of the equation of state and the viscoplastic strength models. Eventually we included spallation in copper and iron and a solid-solid phase transformation in iron to assess the quality of the damage and phase transformation simulations.

  14. Development and reliability testing of a self-report instrument to measure the office layout as a correlate of occupational sitting

    PubMed Central

    2013-01-01

    Background Spatial configurations of office environments assessed by Space Syntax methodologies are related to employee movement patterns. These methods require analysis of floors plans which are not readily available in large population-based studies or otherwise unavailable. Therefore a self-report instrument to assess spatial configurations of office environments using four scales was developed. Methods The scales are: local connectivity (16 items), overall connectivity (11 items), visibility of co-workers (10 items), and proximity of co-workers (5 items). A panel cohort (N = 1154) completed an online survey, only data from individuals employed in office-based occupations (n = 307) were used to assess scale measurement properties. To assess test-retest reliability a separate sample of 37 office-based workers completed the survey on two occasions 7.7 (±3.2) days apart. Redundant scale items were eliminated using factor analysis; Chronbach’s α was used to evaluate internal consistency and test re-test reliability (retest-ICC). ANOVA was employed to examine differences between office types (Private, Shared, Open) as a measure of construct validity. Generalized Linear Models were used to examine relationships between spatial configuration scales and the duration of and frequency of breaks in occupational sitting. Results The number of items on all scales were reduced, Chronbach’s α and ICCs indicated good scale internal consistency and test re-test reliability: local connectivity (5 items; α = 0.70; retest-ICC = 0.84), overall connectivity (6 items; α = 0.86; retest-ICC = 0.87), visibility of co-workers (4 items; α = 0.78; retest-ICC = 0.86), and proximity of co-workers (3 items; α = 0.85; retest-ICC = 0.70). Significant (p ≤ 0.001) differences, in theoretically expected directions, were observed for all scales between office types, except overall connectivity. Significant associations were observed between

  15. Development and reliability testing of a self-report instrument to measure the office layout as a correlate of occupational sitting.

    PubMed

    Duncan, Mitch J; Rashid, Mahbub; Vandelanotte, Corneel; Cutumisu, Nicoleta; Plotnikoff, Ronald C

    2013-02-04

    Spatial configurations of office environments assessed by Space Syntax methodologies are related to employee movement patterns. These methods require analysis of floors plans which are not readily available in large population-based studies or otherwise unavailable. Therefore a self-report instrument to assess spatial configurations of office environments using four scales was developed. The scales are: local connectivity (16 items), overall connectivity (11 items), visibility of co-workers (10 items), and proximity of co-workers (5 items). A panel cohort (N = 1154) completed an online survey, only data from individuals employed in office-based occupations (n = 307) were used to assess scale measurement properties. To assess test-retest reliability a separate sample of 37 office-based workers completed the survey on two occasions 7.7 (±3.2) days apart. Redundant scale items were eliminated using factor analysis; Chronbach's α was used to evaluate internal consistency and test re-test reliability (retest-ICC). ANOVA was employed to examine differences between office types (Private, Shared, Open) as a measure of construct validity. Generalized Linear Models were used to examine relationships between spatial configuration scales and the duration of and frequency of breaks in occupational sitting. The number of items on all scales were reduced, Chronbach's α and ICCs indicated good scale internal consistency and test re-test reliability: local connectivity (5 items; α = 0.70; retest-ICC = 0.84), overall connectivity (6 items; α = 0.86; retest-ICC = 0.87), visibility of co-workers (4 items; α = 0.78; retest-ICC = 0.86), and proximity of co-workers (3 items; α = 0.85; retest-ICC = 0.70). Significant (p ≤ 0.001) differences, in theoretically expected directions, were observed for all scales between office types, except overall connectivity. Significant associations were observed between all scales and occupational sitting behaviour (p ≤ 0.05). All scales have

  16. Metrology target design simulations for accurate and robust scatterometry overlay measurements

    NASA Astrophysics Data System (ADS)

    Ben-Dov, Guy; Tarshish-Shapir, Inna; Gready, David; Ghinovker, Mark; Adel, Mike; Herzel, Eitan; Oh, Soonho; Choi, DongSub; Han, Sang Hyun; El Kodadi, Mohamed; Hwang, Chan; Lee, Jeongjin; Lee, Seung Yoon; Lee, Kuntack

    2016-03-01

    Overlay metrology target design is an essential step prior to performing overlay measurements. This step is done through the optimization of target parameters for a given process stack. A simulation tool is therefore used to improve measurement performances. This work shows how our Metrology Target Design (MTD) simulator helps significantly in the target design process. We show the role of film and Optical CD measurements in improving significantly the fidelity of the simulations. We demonstrate that for various target design parameters we are capable of predicting measured performance metrics by simulations and correctly rank various designs performances.

  17. Office automation.

    PubMed

    Arenson, R L

    1986-03-01

    By now, the term "office automation" should have more meaning for those readers who are not intimately familiar with the subject. Not all of the preceding material pertains to every department or practice, but certainly, word processing and simple telephone management are key items. The size and complexity of the organization will dictate the usefulness of electronic mail and calendar management, and the individual radiologist's personal needs and habits will determine the usefulness of the home computer. Perhaps the most important ingredient for success in the office automation arena relates to the ability to integrate information from various systems in a simple and flexible manner. Unfortunately, this is perhaps the one area that most office automation systems have ignored or handled poorly. In the personal computer world, there has been much emphasis recently on integration of packages such as spreadsheet, database management, word processing, graphics, time management, and communications. This same philosophy of integration has been applied to a few office automation systems, but these are generally vendor-specific and do not allow for a mixture of foreign subsystems. During the next few years, it is likely that a few vendors will emerge as dominant in this integrated office automation field and will stress simplicity and flexibility as major components.

  18. Evaluating the impact of distance measures on deforestation simulations in the fluvial landscapes of amazonia.

    PubMed

    Salonen, Maria; Maeda, Eduardo Eiji; Toivonen, Tuuli

    2014-10-01

    Land use and land cover change (LUCC) models frequently employ different accessibility measures as a proxy for human influence on land change processes. Here, we simulate deforestation in Peruvian Amazonia and evaluate different accessibility measures as LUCC model inputs. We demonstrate how the selection, and different combinations, of accessibility measures impact simulation results. Out of the individual measures, time distance to market center catches the essential aspects of accessibility in our study area. The most accurate simulation is achieved when time distance to market center is used in association with distance to transport network and additional landscape variables. Although traditional Euclidean measures result in clearly lower simulation accuracy when used separately, the combination of two complementary Euclidean measures enhances simulation accuracy significantly. Our results highlight the need for site and context sensitive selection of accessibility variables. More sophisticated accessibility measures can potentially improve LUCC models' spatial accuracy, which often remains low.

  19. Movement Characteristics Analysis and Dynamic Simulation of Collaborative Measuring Robot

    NASA Astrophysics Data System (ADS)

    guoqing, MA; li, LIU; zhenglin, YU; guohua, CAO; yanbin, ZHENG

    2017-03-01

    Human-machine collaboration is becoming increasingly more necessary, and so collaborative robot applications are also in high demand. We selected a UR10 robot as our research subject for this study. First, we applied D-H coordinate transformation of the robot to establish a link system, and we then used inverse transformation to solve the robot’s inverse kinematics and find all the joints. Use Lagrange method to analysis UR robot dynamics; use ADAMS multibody dynamics simulation software to dynamic simulation; verifying the correctness of the derived kinetic models.

  20. Bistatic GPR Measurements in the Egyptian Western Desert - Measured and Simulated data

    NASA Astrophysics Data System (ADS)

    Ciarletti, V.; Le Gall, A.; Berthelier, J.; Ney, R.; Corbel, C.; Dolon, F.

    2006-12-01

    The TAPIR (Terrestrial And Planetary Investigation Radar) instrument has been designed at CETP (Centre d'etude des Environnements Terrestre et Planetaires) to explore the deep Martian subsurface (down to a few kilometers) and to detect liquid water reservoirs. TAPIR is an impulse ground penetrating radar operating at central frequencies ranging from 2 to 4 MHz operating from the surface. In November 2005, an updated version of the instrument working either in monostatic or in bi-static mode was tested in the Egyptian Western Desert. The work presented here focuses on the bi-static measurements performed on the Abou Saied plateau which shows a horizontally layered sub-surface. The electromagnetic signal was transmitted using one of the two orthogonal 70 m loaded electrical dipole antennas of the transmitting GPR. A second GPR, 50 or 100 meters apart, was dedicated to the signal reception. The received waves were characterized by a set of 5 measurements performed on the receiving GPR : the two horizontal components of the electric field and the three composants of the magnetic field. They were used to compute the direction of arrival of the incoming waves and to retrieve more accurately their propagation path and especially to discriminate between waves due to some sub-surface reflecting structure and those due to interaction with the surface clutter. A very efficient synchronization between the two radars enabled us to perform coherent additions up to 2^{31} which improves dramatically the obtained signal to noise ratio. Complementary electromagnetic measurements were conducted on the same site by the LPI (Lunar and Planetary Institute) and the SwRI (Southwest Research Institute). They provided independent information which helped the interpretation of the TAPIR data. Accurate simulations obtained by FDTD taking into account the information available are presented and used for both the interpretation of the measured data and the validation of the instrument.

  1. Ability of College Students to Simulate ADHD on Objective Measures of Attention

    ERIC Educational Resources Information Center

    Booksh, Randee Lee; Pella, Russell D.; Singh, Ashvind N.; Gouvier, William Drew

    2010-01-01

    Objective: The authors examined the ability of college students to simulate ADHD symptoms on objective and self-report measures and the relationship between knowledge of ADHD and ability to simulate ADHD. Method: Undergraduate students were assigned to a control or a simulated ADHD malingering condition and compared with a clinical AD/HD group.…

  2. Simulation of Space Shuttle neutron measurements with FLUKA.

    PubMed

    Pinsky, L; Carminati, F; Ferrari, A

    2001-06-01

    FLUKA is an integrated particle transport code that has enhanced multigroup low-energy neutron transport capability similar to the well-known MORSE transport code. Gammas are produced in groups but many important individual lines are specifically included, and subsequently transported by the main FLUKA routines which use a modified version of EGS4 for electromagnetic (EM) transport. Recoil protons are also transported by the primary FLUKA transport simulation. The neutron cross-section libraries employed within FLUKA were supplied by Giancarlo Panini (ENEA, Italy) based upon the most recent data from JEF-1, JEF-2.2, ENDF/B-VI, JENDL-3, etc. More than 60 different materials are included in the FLUKA databases with temperature ranges including down to cryogenic temperatures. This code has been used extensively to model the neutron environments near high-energy physics experiment shielding. A simulation of the Space Shuttle based upon a spherical aluminum equivalent shielding distribution has been performed with reasonable results. There are good prospects for extending this calculation to a more realistic 3-D geometrical representation of the Shuttle including an accurate representation of its composition, which is an essential ingredient for the improvement of the predictions. A proposed project to develop a combined analysis and simulation package based upon FLUKA and the analysis infrastructure provided by the ROOT software is under active consideration. The code to be developed for this project will be of direct application to the problem of simulating the neutron environment in space, including the albedo effects.

  3. Effects of a Simulated Tennis Match on Lymphocyte Subset Measurements

    ERIC Educational Resources Information Center

    Schafer, Mark; Kell, Holly; Navalta, James; Tibana, Ramires; Lyons, Scott; Arnett, Scott

    2014-01-01

    Tennis is an activity requiring both endurance and anaerobic components, which could have immunosuppressive effects postexercise. Purpose: The purpose of this investigation was to determine the effect of a simulated tennis match on apoptotic and migratory markers on lymphocyte subsets. Method: Male high school (n = 5) and college (n = 3) tennis…

  4. Forecasting Accuracy as a Performance Measure in Business Simulations.

    ERIC Educational Resources Information Center

    Teach, Richard D.

    1993-01-01

    Describes results of a study of business school students that investigated the link between the ability of business simulation team participants to forecast financial and/or market-related outcomes and the actual results of their decision making. Profitability and forecasting errors are discussed, and implications for designing business…

  5. Measures for simulator evaluation of a helicopter obstacle avoidance system

    NASA Technical Reports Server (NTRS)

    Demaio, Joe; Sharkey, Thomas J.; Kennedy, David; Hughes, Micheal; Meade, Perry

    1993-01-01

    The U.S. Army Aeroflightdynamics Directorate (AFDD) has developed a high-fidelity, full-mission simulation facility for the demonstration and evaluation of advanced helicopter mission equipment. The Crew Station Research and Development Facility (CSRDF) provides the capability to conduct one- or two-crew full-mission simulations in a state-of-the-art helicopter simulator. The CSRDF provides a realistic, full field-of-regard visual environment with simulation of state-of-the-art weapons, sensors, and flight control systems. We are using the CSRDF to evaluate the ability of an obstacle avoidance system (OASYS) to support low altitude flight in cluttered terrain using night vision goggles (NVG). The OASYS uses a laser radar to locate obstacles to safe flight in the aircraft's flight path. A major concern is the detection of wires, which can be difficult to see with NVG, but other obstacles--such as trees, poles or the ground--are also a concern. The OASYS symbology is presented to the pilot on a head-up display mounted on the NVG (NVG-HUD). The NVG-HUD presents head-stabilized symbology to the pilot while allowing him to view the image intensified, out-the-window scene through the HUD. Since interference with viewing through the display is a major concern, OASYS symbology must be designed to present usable obstacle clearance information with a minimum of clutter.

  6. Effects of a Simulated Tennis Match on Lymphocyte Subset Measurements

    ERIC Educational Resources Information Center

    Schafer, Mark; Kell, Holly; Navalta, James; Tibana, Ramires; Lyons, Scott; Arnett, Scott

    2014-01-01

    Tennis is an activity requiring both endurance and anaerobic components, which could have immunosuppressive effects postexercise. Purpose: The purpose of this investigation was to determine the effect of a simulated tennis match on apoptotic and migratory markers on lymphocyte subsets. Method: Male high school (n = 5) and college (n = 3) tennis…

  7. Quantum Dynamics Simulations for Modeling Experimental Pump-Probe Measurements

    NASA Astrophysics Data System (ADS)

    Pearson, Brett; Nayyar, Sahil; Liss, Kyle; Weinacht, Thomas

    2016-05-01

    Time-resolved studies of quantum dynamics have benefited greatly from developments in ultrafast table-top and free electron lasers. Advances in computer software and hardware have lowered the barrier for performing calculations such that relatively simple simulations allow for direct comparison with experimental results. We describe here a set of quantum dynamics calculations in low-dimensional molecular systems. The calculations incorporate coupled electronic-nuclear dynamics, including two interactions with an applied field and nuclear wave packet propagation. The simulations were written and carried out by undergraduates as part of a senior research project, with the specific goal of allowing for detailed interpretation of experimental pump-probe data (in additional to the pedagogical value).

  8. Simulation of airborne electromagnetic measurements in three dimensional environments

    SciTech Connect

    Alumbaugh, D.L.; Newman, G.A.

    1994-12-31

    A 3-D frequency domain EM modeling code has been implemented for helicopter electromagnetic (HEM) simulations. A vector Helmholtz formulation for the electric fields is employed to avoid problems associated with the first order Maxwell`s equations numerically decoupling in the air. Additional stability is introduced by formulating the problem in terms of the scattered electric fields which replaces an impressed dipole source with an equivalent source that possesses a much smoother spatial dependence and is easier to model. In older to compute this equivalent source, a primary field arising from dipole sources in a whole space must be calculated where ever the conductivity is different than that of the background. The Helmholtz equation is approximated using finite differences on a staggered grid. After finite differencing, a complex-symmetric matrix system of equations is assembled and preconditioned using Jacobi scaling before it is solved using the quasi-minimum residual (QMR) method. In order to both speed up the solution and allow for larger, more realistic models to be simulated, the scheme has been modified to run on massively parallel architectures. The solution has been compared against other I-D and 3-D numerical models and is found to produce results in good agreement. The versatility of the scheme is demonstrated by simulating a survey over a salt water intrusion zone in the Florida Everglades.

  9. Simulation of fluorescent measurements in the human skin

    NASA Astrophysics Data System (ADS)

    Meglinski, Igor V.; Sinichkin, Yurii P.; Utz, Sergei R.; Pilipenko, Helena A.

    1995-05-01

    Reflectance and fluorescence spectroscopy are successfully used for skin disease diagnostics. Human skin optical parameters are defined by its turbid, scattering properties with nonuniform absorption and fluorescence chromophores distribution, its multilayered structure, and variability under different physiological and pathological conditions. Theoretical modeling of light propagation in skin could improve the understanding of these condition and may be useful in the interpretation of in vivo reflectance and autofluorescence (AF) spectra. Laser application in medical optical tomography, tissue spectroscopy, and phototherapy stimulates the development of optical and mathematical light-tissue interaction models allowing to account the specific features of laser beam and tissue inhomogeneities. This paper presents the version of a Monte Carlo method for simulating of optical radiation propagation in biotissue and highly scattering media, allowing for 3D geometry of a medium. The simulation is based on use of Green's function of medium response to single external pulse. The process of radiation propagation is studied in the area with given boundary conditions, taking into account the processes of reflection and refraction at the boundaries of layers inside the medium under study. Results of Monte Carlo simulation were compared with experimental investigations and demonstrated good agreement.

  10. Simulate what is measured: next steps towards predictive simulations (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Bussmann, Michael; Kluge, Thomas; Debus, Alexander; Hübl, Axel; Garten, Marco; Zacharias, Malte; Vorberger, Jan; Pausch, Richard; Widera, René; Schramm, Ulrich; Cowan, Thomas E.; Irman, Arie; Zeil, Karl; Kraus, Dominik

    2017-05-01

    Simulations of laser matter interaction at extreme intensities that have predictive power are nowadays in reach when considering codes that make optimum use of high performance compute architectures. Nevertheless, this is mostly true for very specific settings where model parameters are very well known from experiment and the underlying plasma dynamics is governed by Maxwell's equations solely. When including atomic effects, prepulse influences, radiation reaction and other physical phenomena things look different. Not only is it harder to evaluate the sensitivity of the simulation result on the variation of the various model parameters but numerical models are less well tested and their combination can lead to subtle side effects that influence the simulation outcome. We propose to make optimum use of future compute hardware to compute statistical and systematic errors rather than just find the mots optimum set of parameters fitting an experiment. This requires to include experimental uncertainties which is a challenge to current state of the art techniques. Moreover, it demands better comparison to experiments as inclusion of simulating the diagnostic's response becomes important. We strongly advocate the use of open standards for finding interoperability between codes for comparison studies, building complete tool chains for simulating laser matter experiments from start to end.

  11. A Structured-Grid Quality Measure for Simulated Hypersonic Flows

    NASA Technical Reports Server (NTRS)

    Alter, Stephen J.

    2004-01-01

    A structured-grid quality measure is proposed, combining three traditional measurements: intersection angles, stretching, and curvature. Quality assesses whether the grid generated provides the best possible tradeoffs in grid stretching and skewness that enable accurate flow predictions, whereas the grid density is assumed to be a constraint imposed by the available computational resources and the desired resolution of the flow field. The usefulness of this quality measure is assessed by comparing heat transfer predictions from grid convergence studies for grids of varying quality in the range of [0.6-0.8] on an 8'half-angle sphere-cone, at laminar, perfect gas, Mach 10 wind tunnel conditions.

  12. Sphericity estimation bias for repeated measures designs in simulation studies.

    PubMed

    Bono, Roser; Arnau, Jaume; Blanca, María J; Alarcón, Rafael

    2016-12-01

    In this study, we explored the accuracy of sphericity estimation and analyzed how the sphericity of covariance matrices may be affected when the latter are derived from simulated data. We analyzed the consequences that normal and nonnormal data generated from an unstructured population covariance matrix-with low (ε = .57) and high (ε = .75) sphericity-can have on the sphericity of the matrix that is fitted to these data. To this end, data were generated for four types of distributions (normal, slightly skewed, moderately skewed, and severely skewed or log-normal), four sample sizes (very small, small, medium, and large), and four values of the within-subjects factor (K = 4, 6, 8, and 10). Normal data were generated using the Cholesky decomposition of the correlation matrix, whereas the Vale-Maurelli method was used to generate nonnormal data. The results indicate the extent to which sphericity is altered by recalculating the covariance matrix on the basis of simulated data. We concluded that bias is greater with spherical covariance matrices, nonnormal distributions, and small sample sizes, and that it increases in line with the value of K. An interaction was also observed between sample size and K: With very small samples, the observed bias was greater as the value of K increased.

  13. Effects of a simulated tennis match on lymphocyte subset measurements.

    PubMed

    Schafer, Mark; Kell, Holly; Navalta, James; Tibana, Ramires; Lyons, Scott; Arnett, Scott

    2014-03-01

    Tennis is an activity requiring both endurance and anaerobic components, which could have immunosuppressive effects postexercise. The purpose of this investigation was to determine the effect of a simulated tennis match on apoptotic and migratory markers on lymphocyte subsets. Male high school (n = 5) and college (n = 3) tennis players (M(age) = 18.9 +/- 3.3 years) completed 10 sets of a tennis protocol including serves, forehand strokes, and backhand groundstrokes with 1-min rest periods between sets. Apoptosis antigen 1 receptor (CD95) and chemokine receptor fractalkine (CX3CR1) expression was analyzed on helper T lymphocytes (CD4+), cytotoxic T lymphocytes (CD8+), and B lymphocytes (CD19+) twice, at resting baseline and immediately after all 10 sets of the tennis protocol. An increase was observed in each lymphocyte subtype (p < .02, effect size = .41), and comparison of absolute changes revealed increases in CD4+/CD95+, CD8+/CD95+, and CD8+/CX3CR1 lymphocytes following the tennis protocol (p < .01, effect size = .43), but not in CD19+ cells. A simulated tennis match has adequate intensity to induce immune modulations in terms of increased cell death and cellular migration in T lymphocyte subsets. Lymphocytopenia following tennis play is influenced by both apoptotic and migratory mechanisms.

  14. Electrochemical concentration measurements for multianalyte mixtures in simulated electrorefiner salt

    NASA Astrophysics Data System (ADS)

    Rappleye, Devin Spencer

    The development of electroanalytical techniques in multianalyte molten salt mixtures, such as those found in used nuclear fuel electrorefiners, would enable in situ, real-time concentration measurements. Such measurements are beneficial for process monitoring, optimization and control, as well as for international safeguards and nuclear material accountancy. Electroanalytical work in molten salts has been limited to single-analyte mixtures with a few exceptions. This work builds upon the knowledge of molten salt electrochemistry by performing electrochemical measurements on molten eutectic LiCl-KCl salt mixture containing two analytes, developing techniques for quantitatively analyzing the measured signals even with an additional signal from another analyte, correlating signals to concentration and identifying improvements in experimental and analytical methodologies. (Abstract shortened by ProQuest.).

  15. Baseline indoor air quality measurements collected from 136 metropolitan New York region commercial office buildings between 1997-1999.

    PubMed

    Springston, John P; Esposito, William A; Cleversey, Keith W

    2002-01-01

    Between January 1997 and December 1999, 648 surveys were performed in 136 commercial office buildings in the metropolitan New York region as part of an ongoing proactive indoor environmental quality (IEQ) program. Sampling was performed on a spot basis in "nonproblem" buildings, during normal business hours, either quarterly or semiannually. Carbon dioxide (CO2), carbon monoxide (CO), and total volatile organic compounds (TVOCs) were among the various physical and gaseous parameters sampled for. More than 15,000 data points were collected, and the results were analyzed to determine the mean, median, mode, and standard deviation for each of those parameters. The data was then compared to various standards and/or guidelines applicable to the indoor environment. The results indicated that 98% of the CO2 readings were below 1000 ppm, and 99.9% of the CO readings were below 10 ppm. However, for TVOCs, nearly 88% of the readings exceeded the proposed European guideline value of 0.3 mg/m3. Ultimately, these results can be used to compare both baseline and periodic readings collected in future studies, and to help determine if potential problems exist within a building.

  16. JOIDES Office

    NASA Astrophysics Data System (ADS)

    The Office of the Joint Oceanographic Institutions for Deep Earth Sampling (JOIDES), the international group of scientific institutions that gives scientific guidance to the Deep Sea Drilling Project (DSDP), will be located at the University of Miami's Rosenstiel School of Marine and Atmospheric Science from July 1, 1982, to June 30, 1984. The university is one of 15 member institutions of JOIDES; 14 of these are active, and 10 are in the United States.While JOIDES is based at the Rosenstiel School, Alan Berman, new dean of the school, will serve as chairman of the group's executive committee. Jose Honnorez, professor of marine geology at Rosenstiel, is chairman of the JOIDES planning committee. He will direct the office, which is responsible for the coordination of the planning committee and 13 advisory panels and nine working groups.

  17. Accuracy of CBCT for volumetric measurement of simulated periapical lesions.

    PubMed

    Ahlowalia, M S; Patel, S; Anwar, H M S; Cama, G; Austin, R S; Wilson, R; Mannocci, F

    2013-06-01

    To compare the accuracy of cone beam computed tomography (CBCT) and micro-computed tomography (μCT) when measuring the volume of bone cavities. Ten irregular-shaped cavities of varying dimensions were created in bovine bone specimens using a rotary diamond bur. The samples were then scanned using the Accuitomo 3D CBCT scanner. The scanned information was converted to the Digital Imaging and Communication in Medicine (DICOM) format ready for analysis. Once formatted, 10 trained and calibrated examiners segmented the scans and measured the volumes of the lesions. Intra/interexaminer agreement was assessed by each examiner re-segmenting each scan after a 2-week interval. Micro-CT scans were analysed by a single examiner. To achieve a physical reading of the artificially created cavities, replicas were created using dimensionally stable silicone impression material. After measuring the mass of each impression sample, the volume was calculated by dividing the mass of each sample by the density of the set impression material. Further corroboration of these measurements was obtained by employing Archimedes' principle to measure the volume of each impression sample. Intraclass correlation was used to assess agreement. Both CBCT (mean volume: 175.9 mm3) and μCT (mean volume: 163.1 mm3) showed a high degree of agreement (intraclass correlation coefficient >0.9) when compared to both weighed and 'Archimedes' principle' measurements (mean volume: 177.7 and 182.6 mm3, respectively). Cone beam computed tomography is an accurate means of measuring volume of artificially created bone cavities in an ex vivo model. This may provide a valuable tool for monitoring the healing rate of apical periodontitis; further investigations are warranted. © 2012 International Endodontic Journal. Published by Blackwell Publishing Ltd.

  18. Radio Occultation Measurements of the Lower Troposphere: A Simulation Study

    NASA Astrophysics Data System (ADS)

    Hurst, K. J.; Ao, C. O.; Mannucci, A. J.

    2011-12-01

    We use simulations to investigate the ability of the Radio Occultation technique to capture the vertical refractivity structure within the Atmospheric Boundary Layer. We first generate a suite of atmospheric profiles of pressure, temperature, water content, and boundary layer height, calculate a suite of forward models to get phase variations which are then run through standard Abel transform-based inversion methods to retrieve the input parameters. We are interested to see if the structure between the bottom and top of the ABL can be resolved in spite of the well known negative bias caused by the large refractivity gradients at the top of the ABL. This study can be used as a basis for comparison with other experimental radio occultation inversion methods.

  19. Measurement and simulation of widespread mobile radio channel characteristics

    NASA Astrophysics Data System (ADS)

    Lorenz, Rudolf Werner

    1989-12-01

    The general model of the transmission characteristics in mobile radio is derived. It is shown which abstractions are necessary to come up with the wide-sense stationary uncorrelated scattering (WSSUS) model. This model, well known from troposcatter propagation, is valid in mobile radio only for small vehicle travel distances. Nevertheless, the WSSUS model proved to be ideal for system test performance in mobile radio. The reasons are explained. A frequency-selective fading simulator recently developed in France and Germany is described, which is based on the WSSUS model and proved to be a very suitable tool for hardware test of mobile radio equipment. The key dates of mobile radio channel characteristics standardized by COST 207 are briefly presented.

  20. Simulation and measurement of a Ka-band HTS MMIC Josephson junction mixer

    NASA Astrophysics Data System (ADS)

    Zhang, Ting; Pegrum, Colin; Du, Jia; Guo, Yingjie Jay

    2017-01-01

    We report modeling and simulation results for a Ka band high-temperature superconducting (HTS) monolithic microwave integrated circuit (MMIC) Josephson junction mixer. A Verilog-A model of a Josephson junction is established and imported into the system simulator to realize a full HTS MMIC circuit simulation containing the HTS passive circuit models. Impedance matching optimization between the junction and passive devices is investigated. Junction DC I-V characteristics, current and local oscillator bias conditions and mixing performance are simulated and compared with the experimental results. Good agreement is obtained between the simulation and measurement results.

  1. Transient water stress in a vegetation canopy - Simulations and measurements

    NASA Technical Reports Server (NTRS)

    Carlson, Toby N.; Belles, James E.; Gillies, Robert R.

    1991-01-01

    Consideration is given to observational and modeling evidence of transient water stress, the effects of the transpiration plateau on the canopy radiometric temperature, and the factors responsible for the onset of the transpiration plateau, such as soil moisture. Attention is also given to the point at which the transient stress can be detected by remote measurement of surface temperature.

  2. Transient water stress in a vegetation canopy - Simulations and measurements

    NASA Technical Reports Server (NTRS)

    Carlson, Toby N.; Belles, James E.; Gillies, Robert R.

    1991-01-01

    Consideration is given to observational and modeling evidence of transient water stress, the effects of the transpiration plateau on the canopy radiometric temperature, and the factors responsible for the onset of the transpiration plateau, such as soil moisture. Attention is also given to the point at which the transient stress can be detected by remote measurement of surface temperature.

  3. Gamma Efficiency Simulations towards Coincidence Measurements for Fusion Cross Sections

    NASA Astrophysics Data System (ADS)

    Heine, M.; Courtin, S.; Fruet, G.; Jenkins, D. G.; Montanari, D.; Morris, L.; Regan, P. H.; Rudigier, M.; Symochko, D.

    2016-10-01

    With the experimental station STELLA (STELlar LAboratory) we will measure fusion cross sections of astrophysical relevance making use of the coincident detection of charged particles and gamma rays for background reduction. For the measurement of gamma rays from the de-excitation of fusion products a compact array of 36 UK FATIMA LaBr3 detectors is designed based on efficiency studies with Geant4. The photo peak efficiency in the region of interest compares to other gamma detection systems used in this field. The features of the internal decay of 138La is used in a background study to obtain an online calibration of the gamma detectors. Background data are fit to the Monte Carlo model of the self activity assuming crude exponential behavior of external background. Accuracy in the region of interest is of the order of some keV in this first study.

  4. Estimating and Measuring Application Latency of Typical Distributed Interactive Simulation (DIS)-Based Simulation Architecture

    DTIC Science & Technology

    2013-03-01

    analysis of state space consistency using a Petri net model (Hodson, 2009). 21 Figure 3: Producer, Network, and Consumer Models by Hodson...used a Petri net model to simulate a consumer/producer system to characterize the age of the state data. This research effort will use actual 24...software architecture, which is based on Hodson’s analysis of state space consistency using Petri net (Hodson, 2009). Figure 4: Multithreaded

  5. Simulated Measurements of Cooling in Muon Ionization Cooling Experiment

    SciTech Connect

    Mohayai, Tanaz; Rogers, Chris; Snopok, Pavel

    2016-06-01

    Cooled muon beams set the basis for the exploration of physics of flavour at a Neutrino Factory and for multi-TeV collisions at a Muon Collider. The international Muon Ionization Cooling Experiment (MICE) measures beam emittance before and after an ionization cooling cell and aims to demonstrate emittance reduction in muon beams. In the current MICE Step IV configuration, the MICE muon beam passes through low-Z absorber material for reducing its transverse emittance through ionization energy loss. Two scintillating fiber tracking detectors, housed in spectrometer solenoid modules upstream and downstream of the absorber are used for reconstructing position and momentum of individual muons for calculating transverse emittance reduction. However, due to existence of non-linear effects in beam optics, transverse emittance growth can be observed. Therefore, it is crucial to develop algorithms that are insensitive to this apparent emittance growth. We describe a different figure of merit for measuring muon cooling which is the direct measurement of the phase space density.

  6. Simulations of Convection Zone Flows and Measurements from Multiple Viewing Angles

    NASA Technical Reports Server (NTRS)

    Duvall, Thomas L.; Hanasoge, Shravan

    2011-01-01

    A deep-focusing time-distance measurement technique has been applied to linear acoustic simulations of a solar interior perturbed by convective flows. The simulations are for the full sphere for r/R greater than 0.2. From these it is straightforward to simulate the observations from different viewing angles and to test how multiple viewing angles enhance detectibility. Some initial results will be presented.

  7. Simulation of the BSDF measurement capabilities for various materials with GCMS-4 gonio-spectrophotometer

    NASA Astrophysics Data System (ADS)

    Zhdanov, Dmitry D.; Potemin, Igor S.; Sokolov, Vadim G.; Garbul, Alexey A.; Voloboy, Alexey G.; Galaktionov, Vladimir A.

    2016-10-01

    Physically accurate lighting simulation requires precise account of the optical properties (BSDF) which are usually measured using gonio-spectrophotometer. In this paper, the authors analyzed the accuracy of BSDF shape measured for later use of measurements in special software for photorealistic visualization and virtual prototyping. Visual and numerical analysis were done. In the first case we look at the sample image rendered under specified lighting conditions, replacing its properties on measurement results and visually estimate the similarity (or difference). In the second case we compare the results of simulation of spatial or angular radiance distribution with results of corresponding radiometric measurements.

  8. Measurement and Simulation of Volatile Particle Emissions from Military Aircraft

    DTIC Science & Technology

    2011-12-01

    HCs and Sulfate • Combustor system studies 0 1 km Carnegie Mellon University Team (WP-1626) • Measurement of PM in engine exhaust • Aging in “ smog ...Stratotanker CFM56-2B Engine Rake Inlet Heated Transfer Line Mobile Laboratory Smog Chamber WP-1626 Engine 1 m DR ~ 1 T ~ 500°C 250 m DR ~ 200 0 2 4 6 8...Dilution sampler, thermodenuder, and smog chamber techniques ● Archival Papers: 7 published, 4 near submission, others in process 25 Primary PM

  9. Observations, Measurements, and Simulations of Convectively Enhanced Carbon Dioxide Dissolution (Invited)

    NASA Astrophysics Data System (ADS)

    Kneafsey, T. J.; Pruess, K.

    2010-12-01

    Carbon dioxide injected into a porous, permeable rock stratum overlain by low-permeability caprock will flow in response to applied pressures and buoyant, viscous, and capillary forces. Four modes of CO2 storage will occur upon injection, which are (in order of increased security and permanence): 1) free-phase supercritical CO2, 2) capillary-trapped CO2, 3) CO2 dissolved into the brine, and 4) CO2 that has chemically reacted with aqueous species and host rock resulting in precipitation. In the target formation, the injected supercritical CO2 will tend to rise due to buoyancy, and accumulate beneath the caprock. At some distance from the injection well, the CO2/brine interface will be roughly horizontal. In the absence of fluid motion, CO2 dissolution into the brine will be dominated by the slow process of molecular diffusion of the CO2 away from the CO2-brine interface, and the rate of dissolution will decrease with time. As CO2 dissolves into the brine, the density of the brine increases by a small amount, on the order of 0.1 to 1%. This results in a fluid dynamics instability because denser fluid overlies less dense fluid, which induces convective flow of the denser fluid downward. The downward convection of the CO2-bearing denser fluid causes less dense brine to flow upwards and contact the CO2. This is a desirable process because it significantly increases the dissolution of CO2 into the brine. We have performed laboratory visualization tests, quantitative measurements at elevated pressures, and numerical simulations to examine this phenomenon. In our visualization tests, we introduce CO2 into the headspace above water containing a pH sensitive indicator contained in a transparent Hele-Shaw cell. When CO2 dissolves into the water, the pH is lowered and the indicator changes color. Upon introduction of CO2 into the cell, a fairly uniform layer of low pH fluid containing dissolved CO2 slowly enlarges downward from the gas-water interface. At some point, many

  10. Operation Sun Beam, Shots Little Feller I, II and Johnie Boy. Project officers report. Project 6. 6. Electromagnetic measurements

    SciTech Connect

    Henderson, W.D.; Livingston, P.M.; Rutter, R.L.

    1985-09-01

    Of considerable interest from both a physical and practical viewpoint is the coupling of electromagnetic energy from a nuclear explosion into various electrical systems in the vicinity of the burst. A series of electromagnetic measurements were made on Shots Little Feller I, Little Feller II, and Johnie Boy. It is clear from the records that radiation shielding must be given closer consideration in future tests. Due to equipment failure and radiation inactivation, only the Johnie Boy dynamic current measurement and the passive peak current indicators on all three events are interpretable.

  11. Simulation of Callisto's exosphere as measured by JUICE/NIM

    NASA Astrophysics Data System (ADS)

    Vorburger, A.; Wurz, P.; Galli, A.; Mousis, O.; Barabash, S.; Lammer, H.

    2014-04-01

    Whereas Callisto's surface has been mapped as early as in 1980 by the two Voyager missions, Callisto's tenuous atmosphere, actually an exosphere, was not directly observed for almost another two decades. In 1999, during the Galileo mission, the Near-Infrared Mapping Spectrometer finally conducted the first and so far only directly measurement of a constituent in Callisto's exosphere: A layer of CO2 molecules reaching up to 100 km above the surface [2]. During the same mission, an ionospheric layer was discovered above Callisto's sunlit trailing hemisphere [5]. The photo-ionization of the observed neutral CO2 atmosphere is insufficient to produce the observed electron densities, though. The existence of a neutral exosphere consisting primarily of O2 was thus proposed, models of which agree well with O2 upper limits derived from Hubble Space Telescope measurements [8]. The Neutral Ion Mass Spectrometer of the Particle Environment Package on board the planned JUpiter ICy moons Explorer mission will conduct the first-ever direct sampling of the exospheres of Europa, Ganymede, and Callisto. We present here density profiles of all primary constituents expected to be present in Callisto's exosphere, and mass spectra as we expect them to be recorded by NIM.

  12. Comparisons of EOS MLS cloud ice measurements with ECMWF analyses and GCM simulations : initial results

    NASA Technical Reports Server (NTRS)

    Li, J. - L.; Waliser, D. E.; Jiang, J. H.; Wu, D. L.; Read, W.; Waters, J. W.

    2005-01-01

    To assess the status of global climate models (GCMs) in simulating upper-tropospheric ice water content (IWC), a new set of IWC measurements from the Earth Observing System's Microwave Limb Sounder (MLS) are used. Comparisons are made with ECMWF analyses and simulations from several GCMs, including two with multi-scale-modeling framework.

  13. Fluorescence cross section measurements of biological agent simulants

    SciTech Connect

    Stephens, J.R.

    1996-11-01

    Fluorescence is a powerful technique that has potential uses in detection and characterization of biological aerosols both in the battlefield and in civilian environments. Fluorescence techniques can be used with ultraviolet (UV) light detection and ranging (LIDAR) equipment to detect biological aerosol clouds at a distance, to provide early warning of a biological attack, and to track an potentially noxious cloud. Fluorescence can also be used for detection in a point sensor to monitor biological materials and to distinguish agents from benign aerosols. This work is part of a continuing program by the Army`s Chemical and Biological Defense Command to characterized the optical properties of biological agents. Reported here are ultraviolet fluorescence measurements of Bacillus megaterium and Bacillus Globigii aerosols suspended in an electrodynamic particle trap. Fluorescence spectra of a common atmospheric aerosol, pine pollen, are also presented.

  14. Measurements and simulation of the flow around a poppet valve

    NASA Astrophysics Data System (ADS)

    Lilek, Z.; Nadarajah, S.; Peric, M.; Tindal, M. J.; Yianneskis, M.

    The flow through an axisymmetric inlet port was investigated experimentally and numerically. Laser-Doppler anemometry was used to measure the three ensemble-averaged mean and rms velocity components for two valve lifts, 6 and 10 mm. Numerical calculations of the flows were carried out using a finite volume multigrid method and a standard k-epsilon turbulence model. Comparison of the predictions with the experimental results shows good agreement for the mean velocities for the 10 mm lift case. However, for the 6 mm liftcase the predicted flow differs substantially from the experimental results. This indicates the extreme sensitivity of the flow to the valve lift and the need for more sophisticated turbulence modeling when predicting such flows.

  15. Experimental measurement of investment shell properties and use of the data in casting simulation software

    SciTech Connect

    Browne, D.J.; Sayers, K.

    1995-12-31

    This paper describes the development of a systematic program of experimental measurement of relevant properties of mould materials, conducted with the express purpose of generating data for use in casting (filling and solidification) simulation software. In particular the thermophysical properties of the ceramic shell built up for the investment casting process are measured. These properties include specific heat capacity, thermal conductivity, gas permeability, density and surface emissivity. Much of the experimental measurements are taken as a function of temperature, up to the temperature at which moulds are typically fired or preheated. Typical results are presented. The data so generated is then used in a casting simulation model to simulate the investment casting of a prosthetic device. The results of the simulation are presented, and comparisons are made with measurements and observations from an experimental casting of the same part. In this way both the reliability of the data and the accuracy of the filling and solidification model are validated.

  16. A three-axis flight simulator. [for testing and evaluating inertial measuring units, and flight platforms

    NASA Technical Reports Server (NTRS)

    Mason, M. G.

    1975-01-01

    A simulator is described, which was designed for testing and evaluating inertial measuring units, and flight platforms. Mechanical and electrical specifications for the outer, middle, and inner axis are presented. Test results are included.

  17. Variations of measured and simulated soil-loss amounts in a semiarid area in Turkey.

    PubMed

    Hacisalihoğlu, Sezgin

    2010-06-01

    The main goal of this research was soil-loss determination and comparison of the plot measurement results with simulation model (universal soil loss equation (USLE)) results in different land use and slope classes. The research took place in three different land-use types (Scotch pine forest, pasture land, and agricultural land) and in two different slope classes (15-20%, 35-40%). Within six measurement stations (for each land-use type and slope class-one station), totally 18 measurement plots have been constituted, and soil-loss amount measurements have been investigated during the research period (3 years along). USLE simulation model is used in these measurement plots for calculation the soil-loss amounts. The results pointed out that measured (in plots) and simulated (with USLE) soil-loss amounts differ significantly in each land-use type and slope class.

  18. Operation Dominic. Christmas and Fish Bowl Series. Project Officers report -- Project 7. 1. Electromagnetic signal, underwater measurements

    SciTech Connect

    Bridges, A.P.; Bittner, B.J.; Peckham, V.D.; Moorhead, A.D.; Cole, E.L.

    1985-04-01

    This project was conducted to obtain measurements of the electromangetic (EM) signals from nuclear detonations at large distances from the detonation point, above and beneath the sea surface. The planned use of the data is that of determining the feasibility of an Indirect Bomb Damage Assessment (IBDA) system based on the nuclear EM signature. The specific tests were conducted from two ships. The EM signatures recorded both above and below the water surface for the various nuclear events are unique, recognizable, and predictable to a useful degree. It appears entirely feasible to utilize this nuclear EM signal as a method of IBDA. The significance of the data presented herein lies primarily in the demonstrated ability to detect an above-water EM signal with an underwater antenna system. Signal characteristics are changed in magnitude and phase but are very easily recognizable with but a minimum of measuring equipment.

  19. OPERATION DOMINIC, FISH BOWL SERIES. Project Officer’s Report. Project 9.1b. Ionospheric Wind and Diffusion Measurements

    DTIC Science & Technology

    1985-09-01

    varies as log of the light intensity within the increment. The trail material employed in the measurements was sodium, although lithium and potassium...the down trail was also clearly visible on the first three observations, the « hole trajectory could be incioded. Knowing the azimuth and zenith...were coupled with a unique pattern of wind directions. A double shear (or corkscrew change through 350 degrees) between 85 and 100 km was observed

  20. Stray fields of domains in permalloy microstructures—Measurements and simulations

    NASA Astrophysics Data System (ADS)

    Barthelmess, M.; Pels, C.; Thieme, A.; Meier, G.

    2004-05-01

    We have measured the stray fields of thin permalloy (Ni83Fe17) microstructures with different geometries and several thicknesses by magnetic-force microscopy (MFM). The MFM images are compared to corresponding images calculated from micromagnetic simulations. In particular, the type of 180° domain walls is discussed. We observe a transition from cross-tie to asymmetric Bloch walls between 70 and 100 nm film thickness. Good agreement between measurement and simulation is obtained.

  1. Advanced Simulator for Pilot Training: Design of Automated Performance Measurement System

    DTIC Science & Technology

    1980-08-01

    reverse aide if necessary and identify by block number) pilot pertormance measurement Advanced Simulator for Pilot Training ( ASPT ) Aircrew performance...Simulator for Pilot Training ( ASPT ). This report documents that development effort and describes the current status of the measurement system. It was...Continued): cj;? /To date, the following scenarios have been implemented on the ASPT : (a)1’nusition Tasks - Straight and Level, Airspeed Changes, Turns

  2. Simulation of space measurements of vegetation canopy bidirectional reflectance factors

    NASA Technical Reports Server (NTRS)

    Myneni, R. B.; Asrar, G.

    1992-01-01

    A vegetation canopy receives both monodirectional and scattered radiation which is then reflected back into the atmosphere according to its bidirectional reflectance distribution function (BRDF). Remote measurements are typically the angular and spectral distributions of radiations exiting the atmosphere. The evaluation of vegetation canopy bidirectional reflectance factors requires a numerical solution of the canopy radiative transfer equation. A horizontally homogeneous vegetation canopy, of finite physical depth, filled densely with small leaves and bounded by a flat Lambertian ground surface is considered. The canopy is illuminated spatially uniformly by monodirectional radiation. The scattered intensity distribution emerging at the top of the canopy in all directions in the upper hemisphere is evaluated. The magnitude, sign and angular distribution of atmospheric effects are wavelength specific and depend on the composition of the atmosphere. The net atmospheric effect is positive (negative) at the red (near-infrared) wavelength due to strong scattering (absorption) in the atmosphere. The angular distribution of these effects is bowl-shaped. Thus, off-nadir remote observations, especially at shorter wavelengths, are most affected by atmospheric perturbations.

  3. Evidence-based ergonomics. A comparison of Japanese and American office layouts.

    PubMed

    Noro, Kageyu; Fujimaki, Goroh; Kishi, Shinsuke

    2003-01-01

    There is a variety of alternatives in office layouts. Yet the theoretical basis and criteria for predicting how well these layouts accommodate employees are poorly understood. The objective of this study was to evaluate criteria for selecting office layouts. Intensive computer workers worked in simulated office layouts in a controlled experimental laboratory. Eye movement measures indicate that knowledge work requires both concentration and interaction. Findings pointed to one layout as providing optimum balance between these 2 requirements. Recommendations for establishing a theoretical basis and design criteria for selecting office layouts based on work style are suggested.

  4. Soil moisture at local scale: Measurements and simulations

    NASA Astrophysics Data System (ADS)

    Romano, Nunzio

    2014-08-01

    Soil moisture refers to the water present in the uppermost part of a field soil and is a state variable controlling a wide array of ecological, hydrological, geotechnical, and meteorological processes. The literature on soil moisture is very extensive and is developing so rapidly that it might be considered ambitious to seek to present the state of the art concerning research into this key variable. Even when covering investigations about only one aspect of the problem, there is a risk of some inevitable omission. A specific feature of the present essay, which may make this overview if not comprehensive at least of particular interest, is that the reader is guided through the various traditional and more up-to-date methods by the central thread of techniques developed to measure soil moisture interwoven with applications of modeling tools that exploit the observed datasets. This paper restricts its analysis to the evolution of soil moisture at the local (spatial) scale. Though a somewhat loosely defined term, it is linked here to a characteristic length of the soil volume investigated by the soil moisture sensing probe. After presenting the most common concepts and definitions about the amount of water stored in a certain volume of soil close to the land surface, this paper proceeds to review ground-based methods for monitoring soil moisture and evaluates modeling tools for the analysis of the gathered information in various applications. Concluding remarks address questions of monitoring and modeling of soil moisture at scales larger than the local scale with the related issue of data aggregation. An extensive, but not exhaustive, list of references is provided, enabling the reader to gain further insights into this subject.

  5. Combining Disparate Measures of Metabolic Rate During Simulated Spacewalks

    NASA Technical Reports Server (NTRS)

    Feiveson, Alan H.; Kuznetz, Larry; Nguyen, Dan

    2009-01-01

    Scientists from NASA's Extravehicular Activities (EVA) Physiology Systems and Performance Project help design space suits for future missions, during which astronauts are expected to perform EVA activities on the Lunar or Martian surface. During an EVA, an astronaut s integrated metabolic rate is used to predict how much longer the activity can continue and still provide a safe margin of remaining consumables. For EVAs in the Apollo era, NASA physicians monitored live data feeds of heart rate, O2 consumption, and liquid cooled garment (LCG) temperatures, which were subjectively combined or compared to produce an estimate of metabolic rate. But these multiple data feeds sometimes provided conflicting estimates of metabolic rate, making real-time calculations of remaining time difficult for physician/monitors. Currently, designs planned for the Constellation Program EVAs utilize an automated, but largely heuristic methodology for incorporating the above three measurements, plus an additional one - CO2 production, ignoring data that appears in conflict; however a more rigorous model-based approach is desirable. In this study, we show how principal axis factor analysis, in combination with OLS regression and LOWESS smoothing can be used to estimate metabolic rate as a data-driven weighted average of heart rate, O2 consumption, LCG temperature data, and CO2 production. Preliminary results suggest less sensitivity to occasional spikes in observed data feeds, and reasonable within-subject reproducibility when applied to subsequent tasks. These methods do not require physician monitoring and as such can be automated in the electronic components of future space suits. With additional validation, our models show promise for increasing astronaut safety, while reducing the need for and potential errors associated with human monitoring of multiple systems.

  6. Combining Disparate Measures of Metabolic Rate During Simulated Spacewalks

    NASA Technical Reports Server (NTRS)

    Feiveson, Alan H.; Kuznetz, Larry; Nguyen, Dan

    2009-01-01

    Scientists from NASA's Extravehicular Activities (EVA) Physiology Systems and Performance Project help design space suits for future missions, during which astronauts are expected to perform EVA activities on the Lunar or Martian surface. During an EVA, an astronaut s integrated metabolic rate is used to predict how much longer the activity can continue and still provide a safe margin of remaining consumables. For EVAs in the Apollo era, NASA physicians monitored live data feeds of heart rate, O2 consumption, and liquid cooled garment (LCG) temperatures, which were subjectively combined or compared to produce an estimate of metabolic rate. But these multiple data feeds sometimes provided conflicting estimates of metabolic rate, making real-time calculations of remaining time difficult for physician/monitors. Currently, designs planned for the Constellation Program EVAs utilize an automated, but largely heuristic methodology for incorporating the above three measurements, plus an additional one - CO2 production, ignoring data that appears in conflict; however a more rigorous model-based approach is desirable. In this study, we show how principal axis factor analysis, in combination with OLS regression and LOWESS smoothing can be used to estimate metabolic rate as a data-driven weighted average of heart rate, O2 consumption, LCG temperature data, and CO2 production. Preliminary results suggest less sensitivity to occasional spikes in observed data feeds, and reasonable within-subject reproducibility when applied to subsequent tasks. These methods do not require physician monitoring and as such can be automated in the electronic components of future space suits. With additional validation, our models show promise for increasing astronaut safety, while reducing the need for and potential errors associated with human monitoring of multiple systems.

  7. Effectiveness of online simulation training: Measuring faculty knowledge, perceptions, and intention to adopt.

    PubMed

    Kim, Sujeong; Park, Chang; O'Rourke, Jennifer

    2017-04-01

    Best practice standards of simulation recommend standardized simulation training for nursing faculty. Online training may offer an effective and more widely available alternative to in-person training. Using the Theory of Planned Behavior, this study evaluated the effectiveness of an online simulation training program, examining faculty's foundational knowledge of simulation as well as perceptions and intention to adopt. One-group pretest-posttest design. A large school of nursing with a main campus and five regional campuses in the Midwestern United States. Convenience sample of 52 faculty participants. Knowledge of foundational simulation principles was measured by pre/post-training module quizzes. Perceptions and the intention to adopt simulation were measured using the Faculty Attitudes and Intent to Use Related to the Human Patient Simulator questionnaire. There was a significant improvement in faculty knowledge after training and observable improvements in attitudes. Attitudes significantly influenced the intention to adopt simulation (B=2.54, p<0.001). Online simulation training provides an effective alternative for training large numbers of nursing faculty who seek to implement best practice of standards within their institutions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Martian dust threshold measurements: Simulations under heated surface conditions

    NASA Technical Reports Server (NTRS)

    White, Bruce R.; Greeley, Ronald; Leach, Rodman N.

    1991-01-01

    Diurnal changes in solar radiation on Mars set up a cycle of cooling and heating of the planetary boundary layer, this effect strongly influences the wind field. The stratification of the air layer is stable in early morning since the ground is cooler than the air above it. When the ground is heated and becomes warmer than the air its heat is transferred to the air above it. The heated parcels of air near the surface will, in effect, increase the near surface wind speed or increase the aeolian surface stress the wind has upon the surface when compared to an unheated or cooled surface. This means that for the same wind speed at a fixed height above the surface, ground-level shear stress will be greater for the heated surface than an unheated surface. Thus, it is possible to obtain saltation threshold conditions at lower mean wind speeds when the surface is heated. Even though the mean wind speed is less when the surface is heated, the surface shear stress required to initiate particle movement remains the same in both cases. To investigate this phenomenon, low-density surface dust aeolian threshold measurements have been made in the MARSWIT wind tunnel located at NASA Ames Research Center, Moffett Field, California. The first series of tests examined threshold values of the 100 micron sand material. At 13 mb surface pressure the unheated surface had a threshold friction speed of 2.93 m/s (and approximately corresponded to a velocity of 41.4 m/s at a height of 1 meter) while the heated surface equivalent bulk Richardson number of -0.02, yielded a threshold friction speed of 2.67 m/s (and approximately corresponded to a velocity of 38.0 m/s at a height of 1 meter). This change represents an 8.8 percent decrease in threshold conditions for the heated case. The values of velocities are well within the threshold range as observed by Arvidson et al., 1983. As the surface was heated the threshold decreased. At a value of bulk Richardson number equal to -0.02 the threshold

  9. Comparison of Analysis, Simulation, and Measurement of Wire-to-Wire Crosstalk. Part 1

    NASA Technical Reports Server (NTRS)

    Bradley, Arthur T.; Yavoich, Brian James; Hodson, Shame M.; Godley, Richard Franklin

    2010-01-01

    In this investigation, we compare crosstalk analysis, simulation, and measurement results for electrically short configurations. Methods include hand calculations, PSPICE simulations, Microstripes transient field solver, and empirical measurement. In total, four representative physical configurations are examined, including a single wire over a ground plane, a twisted pair over a ground plane, generator plus receptor wires inside a cylindrical conduit, and a single receptor wire inside a cylindrical conduit. Part 1 addresses the first two cases, and Part 2 addresses the final two. Agreement between the analysis, simulation, and test data is shown to be very good.

  10. In-vehicle CO ingression: validation through field measurements and mass balance simulations.

    PubMed

    Esber, Layale Abi; El-Fadel, Mutasem

    2008-05-01

    In this study a mass balance modeling approach with measured out-vehicle carbon monoxide (CO) levels and trip-specific movement record as boundary conditions were used to simulate in-vehicle CO concentration profiles. The simulation results were coupled with field measurements to demonstrate the occurrence of CO ingression into the vehicle compartment from the engine combustion and/or exhaust return of the test vehicle. Agreement between field and simulation results was obtained for variable amounts of infiltrated CO equivalent to an in-vehicle emission rate of 250 to 1250 mg/h of CO depending on the vehicle ventilation settings.

  11. Software simulator for design and optimization of the kaleidoscopes for the surface reflectance measurement

    NASA Astrophysics Data System (ADS)

    Havran, Vlastimil; Bittner, Jiří; Čáp, Jiří; Hošek, Jan; Macúchová, Karolina; Němcová, Šárka

    2015-01-01

    Realistic reproduction of appearance of real-world materials by means of computer graphics requires accurate measurement and reconstruction of surface reflectance properties. We propose an interactive software simulation tool for modeling properties of a kaleidoscopic optical system for surface reflectance measurement. We use ray tracing to obtain fine grain simulation results corresponding to the resolution of a simulated image sensor and computing the reflections inside this system based on planar mirrors. We allow for a simulation of different geometric configurations of a kaleidoscope such as the number of mirrors, the length, and the taper angle. For accelerating the computation and delivering interactivity we use parallel processing of large groups of rays. Apart from the interactive mode our tool also features batch optimization suitable for automatic search for optimized kaleidoscope designs. We discuss the possibilities of the simulation and present some preliminary results obtained by using it in practice.

  12. Development of a Comprehensive Mathematical Model for Simulating the Effects of Misalignments in Vibration Measurements using Scanning LDV Measurement Systems

    NASA Astrophysics Data System (ADS)

    Di Battista, S.; Di Maio, D.; Ewins, D. J.; Castellini, P.; Tomasini, E. P.

    2010-05-01

    Scanning mirrors are very important contributors of a SLDV system. These mirrors are often installed inside the laser head thereby the optical access of the targeted structure must be always available during testing. However, some applications could benefit of having a laser head decoupled from the scanner so to positioning the twos in an optimum way, although this can introduce possible sources of misalignments. This paper presents the development of a mathematical model for simulating the effects of misalignment in vibration measurements using scanning LDV measurement systems. The misalignments between the laser source and the scanning unit, and between the latter and the target structure is a source of uncertainty, producing pseudo-vibrations and causing relative motion of the laser beam on the target surface. Using such a mathematical model, the effects of each parameter of misalignment can be simulated and studied. This work aims to presents simulations of all sources of misalignments when the scanners are decoupled from the laser head.

  13. Operation Dominic, Fish Bowl Series. Project Officer's report. Project 9. 1b. Ionospheric wind and diffusion measurements

    SciTech Connect

    Champion, K.; Manring, E.R.

    1985-09-01

    The aim of this project was to measure high-altitude wind velocities and diffusion coefficients in the altitude region between 60 and 150 km. The method involved the ejection of a sodium vapor trail from a Cajun rocket at dust or dawn twilight. The sodium was sunlit, and as a result of emission of resonance radiation, was visible against a darkened background for about 20 minutes. The trail was photographed simultaneously from four different sites, allowing for subsequent triangulation to determine the altitude of various parts of the cloud. A major application of these wind and diffusion data, taken at dusk and dawn following the high-altitude nuclear tests, was to aid in determining the disposition of the nuclear debris.

  14. Cost estimation of hypertension management based on home blood pressure monitoring alone or combined office and ambulatory blood pressure measurements.

    PubMed

    Boubouchairopoulou, Nadia; Karpettas, Nikos; Athanasakis, Kostas; Kollias, Anastasios; Protogerou, Athanase D; Achimastos, Apostolos; Stergiou, George S

    2014-10-01

    This study aims at estimating the resources consumed and subsequent costs for hypertension management, using home blood pressure (BP) monitoring (HBPM) alone versus combined clinic measurements and ambulatory blood pressure monitoring (C/ABPM). One hundred sixteen untreated hypertensive subjects were randomized to use HBPM or C/ABPM for antihypertensive treatment initiation and titration. Health resources utilized within 12-months follow-up, their respective costs, and hypertension control were assessed. The total cost of the first year of hypertension management was lower in HBPM than C/ABPM arm (€1336.0 vs. €1473.5 per subject, respectively; P < .001). Laboratory tests' cost was identical in both arms. There was no difference in achieved BP control and drug expenditure (HBPM: €233.1 per subject; C/ABPM: €247.6 per subject; P = not significant), whereas the cost of BP measurements and/or visits was higher in C/ABPM arm (€393.9 vs. €516.9, per patient, respectively P < .001). The cost for subsequent years (>1) was €348.9 and €440.2 per subject, respectively for HBPM and C/ABPM arm and €2731.4 versus €3234.3 per subject, respectively (P < .001) for a 5-year projection. HBPM used alone for the first year of hypertension management presents lower cost than C/ABPM, and the same trend is observed in 5-year projection. The results on the resources consumption can be used to make cost estimates for other health-care systems.

  15. RSRM top hat cover simulator lightning test, volume 2. Appendix A: Resistance measurements. Appendix B: Lightning test data plots

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Resistance measurements are given in graphical for when a simulated lightning discharge strikes on an exposed top hat cover simulator. The test sequence was to measure the electric and magnetic fields induced inside a redesigned solid rocket motor case.

  16. Determining minimum alarm activities of orphan sources in scrap loads; Monte Carlo simulations, validated with measurements

    NASA Astrophysics Data System (ADS)

    Takoudis, G.; Xanthos, S.; Clouvas, A.; Potiriadis, C.

    2010-02-01

    Portal monitoring radiation detectors are commonly used by steel industries in the probing and detection of radioactivity contamination in scrap metal. These portal monitors typically consist of polystyrene or polyvinyltoluene (PVT) plastic scintillating detectors, one or more photomultiplier tubes (PMT), an electronic circuit, a controller that handles data output and manipulation linking the system to a display or a computer with appropriate software and usually, a light guide. Such a portal used by the steel industry was opened and all principal materials were simulated using a Monte Carlo simulation tool (MCNP4C2). Various source-detector configurations were simulated and validated by comparison with corresponding measurements. Subsequently an experiment with a uniform cargo along with two sets of experiments with different scrap loads and radioactive sources ( 137Cs, 152Eu) were performed and simulated. Simulated and measured results suggested that the nature of scrap is crucial when simulating scrap load-detector experiments. Using the same simulating configuration, a series of runs were performed in order to estimate minimum alarm activities for 137Cs, 60Co and 192Ir sources for various simulated scrap densities. The minimum alarm activities as well as the positions in which they were recorded are presented and discussed.

  17. Comparison Between Numerically Simulated and Experimentally Measured Flowfield Quantities Behind a Pulsejet

    NASA Technical Reports Server (NTRS)

    Geng, Tao; Paxson, Daniel E.; Zheng, Fei; Kuznetsov, Andrey V.; Roberts, William L.

    2008-01-01

    Pulsed combustion is receiving renewed interest as a potential route to higher performance in air breathing propulsion systems. Pulsejets offer a simple experimental device with which to study unsteady combustion phenomena and validate simulations. Previous computational fluid dynamic (CFD) simulation work focused primarily on the pulsejet combustion and exhaust processes. This paper describes a new inlet sub-model which simulates the fluidic and mechanical operation of a valved pulsejet head. The governing equations for this sub-model are described. Sub-model validation is provided through comparisons of simulated and experimentally measured reed valve motion, and time averaged inlet mass flow rate. The updated pulsejet simulation, with the inlet sub-model implemented, is validated through comparison with experimentally measured combustion chamber pressure, inlet mass flow rate, operational frequency, and thrust. Additionally, the simulated pulsejet exhaust flowfield, which is dominated by a starting vortex ring, is compared with particle imaging velocimetry (PIV) measurements on the bases of velocity, vorticity, and vortex location. The results show good agreement between simulated and experimental data. The inlet sub-model is shown to be critical for the successful modeling of pulsejet operation. This sub-model correctly predicts both the inlet mass flow rate and its phase relationship with the combustion chamber pressure. As a result, the predicted pulsejet thrust agrees very well with experimental data.

  18. MCNPX simulation of influence of cosmic rays on low-activity spectrometric measurements

    NASA Astrophysics Data System (ADS)

    Šolc, Jaroslav; Kovář, Petr; Dryák, Pavel

    2014-02-01

    Germanium gamma spectrometers are effective instruments for low-activity measurement of a mixture of radionuclides in environmental samples, food samples, in materials released from nuclear facilities to the environment, etc. In such measurements cosmic rays have a significant contribution to the background signal. A Monte Carlo code MCNPXTM was used to calculate coaxial high-purity germanium (HPGe) detector pulse-height spectra caused by cosmic rays penetrating through shielding made of concrete and lead. Simulations were compared to two different measurements, one performed inside a 10 cm thick lead shielding and another done inside a larger chamber made of low-activity concrete and with several ceiling thicknesses. In the first experiment, a discrepancy was found between simulated and measured spectra by up to the factor of 4 at 2.62 MeV and slowly decreasing to unity at 13 MeV. It is assumed that the discrepancy between the measured and simulated spectra is caused by the simplification of muon energy losses treatment resulting in the underestimation of count rate in simulated pulse-height spectrum. Good agreement was obtained between simulation and measurement of differences of detector count rates in 662 keV and 1332 keV energy windows inside a concrete chamber with varying ceiling thickness. It is assumed that due to lower effective Z of concrete, delta electron bremsstrahlung has lower yield and the muon radiation energy losses start to be important at higher energies than in lead. As a result, the total contribution of these effects to the outputs of MCNPXTM simulations of concrete chamber is not dominant in the investigated energy windows and the simulation results are in a close agreement with the measurement.

  19. Uncertainty Analysis of Sonic Boom Levels Measured in a Simulator at NASA Langley

    NASA Technical Reports Server (NTRS)

    Rathsam, Jonathan; Ely, Jeffry W.

    2012-01-01

    A sonic boom simulator has been constructed at NASA Langley Research Center for testing the human response to sonic booms heard indoors. Like all measured quantities, sonic boom levels in the simulator are subject to systematic and random errors. To quantify these errors, and their net influence on the measurement result, a formal uncertainty analysis is conducted. Knowledge of the measurement uncertainty, or range of values attributable to the quantity being measured, enables reliable comparisons among measurements at different locations in the simulator as well as comparisons with field data or laboratory data from other simulators. The analysis reported here accounts for acoustic excitation from two sets of loudspeakers: one loudspeaker set at the facility exterior that reproduces the exterior sonic boom waveform and a second set of interior loudspeakers for reproducing indoor rattle sounds. The analysis also addresses the effect of pressure fluctuations generated when exterior doors of the building housing the simulator are opened. An uncertainty budget is assembled to document each uncertainty component, its sensitivity coefficient, and the combined standard uncertainty. The latter quantity will be reported alongside measurement results in future research reports to indicate data reliability.

  20. Quantitative analyses of spectral measurement error based on Monte-Carlo simulation

    NASA Astrophysics Data System (ADS)

    Jiang, Jingying; Ma, Congcong; Zhang, Qi; Lu, Junsheng; Xu, Kexin

    2015-03-01

    The spectral measurement error is controlled by the resolution and the sensitivity of the spectroscopic instrument and the instability of involved environment. In this talk, the spectral measurement error has been analyzed quantitatively by using the Monte Carlo (MC) simulation. Take the floating reference point measurement for example, unavoidably there is a deviation between the measuring position and the theoretical position due to various influence factors. In order to determine the error caused by the positioning accuracy of the measuring device, Monte Carlo simulation has been carried out at the wavelength of 1310nm, simulating Intralipid solution of 2%. MC simulation was performed with the number of 1010 photons and the sampling interval of the ring at 1μm. The data from MC simulation will be analyzed on the basis of thinning and calculating method (TCM) proposed in this talk. The results indicate that TCM could be used to quantitatively analyze the spectral measurement error brought by the positioning inaccuracy.

  1. Measurements of tibial rotation during a simulated pivot shift manoeuvre using a gyroscopic sensor.

    PubMed

    Petrigliano, Frank A; Borgstrom, Per Henrik; Kaiser, William J; McAllister, David R; Markolf, Keith L

    2015-08-01

    The pivot shift has been correlated with patient-reported outcomes and knee function following ACL injury and reconstruction. Tibial rotation has been recognized as an important component to the pivot shift motion path. However, few methodologies exist to quantify tibial rotation in the clinical setting. The purpose of this study was to validate the use of a wireless gyroscopic sensor to measure axial rotation of the tibia during a manually simulated pivot shift manoeuvre in cadaveric specimens. We hypothesized that integrated gyroscopic measurements of tibial rotation velocity (tibial rotation) would be highly correlated with tibial rotations simultaneously recorded with a rotary potentiometer during a simulated pivot shift motion under intact and ACL-deficient conditions. Gyroscopic measurements of rotational velocity were integrated and calibrated to a known arc of rotation. The gyroscope was mounted on the distal tibia with its axis aligned to the tibial shaft. Ten simulations of a pivot shift motion pathway were performed on nine cadaveric knees under intact and ACL-deficient conditions. Logistic regression was used to compare gyroscopic and potentiometer measurements of tibial rotation for both test conditions. Gyroscopic measurements of maximum external tibial rotation during the simulated pivot shift motion pathway were strongly correlated with potentiometer measurements of external tibial rotation in both the intact and ACL-deficient states (R (2) = 0.984). The gyroscope evaluated in this cadaveric study was capable of accurately recording tibial rotation during a simulated pivot shift motion pathway.

  2. Monte Carlo simulation of air sampling methods for the measurement of radon decay products.

    PubMed

    Sima, Octavian; Luca, Aurelian; Sahagia, Maria

    2017-02-21

    A stochastic model of the processes involved in the measurement of the activity of the (222)Rn decay products was developed. The distributions of the relevant factors, including air sampling and radionuclide collection, are propagated using Monte Carlo simulation to the final distribution of the measurement results. The uncertainties of the (222)Rn decay products concentrations in the air are realistically evaluated.

  3. Coupling impedance of an in-vacuum undulator. Measurement, simulation, and analytical estimation

    SciTech Connect

    Simaluk, Victor; Blednykh, Alexei; Fielder, Richard; Rehm, Guenther; Bartolini, Riccardo

    2014-07-25

    One of the important issues of the in-vacuum undulator design is the coupling impedance of the vacuum chamber, which includes tapered transitions with variable gap size. In order to get complete and reliable information on the impedance, analytical estimate, numerical simulations and beam-based measurements have been performed at Diamond Light Source, a forthcoming upgrade of which includes introducing additional insertion device (ID) straights. Moreover, the impedance of an already existing ID vessel geometrically similar to the new one has been measured using the orbit bump method. The measurement results in comparison with analytical estimations and numerical simulations are discussed in this paper.

  4. Coupling impedance of an in-vacuum undulator: Measurement, simulation, and analytical estimation

    NASA Astrophysics Data System (ADS)

    Smaluk, Victor; Fielder, Richard; Blednykh, Alexei; Rehm, Guenther; Bartolini, Riccardo

    2014-07-01

    One of the important issues of the in-vacuum undulator design is the coupling impedance of the vacuum chamber, which includes tapered transitions with variable gap size. To get complete and reliable information on the impedance, analytical estimate, numerical simulations and beam-based measurements have been performed at Diamond Light Source, a forthcoming upgrade of which includes introducing additional insertion device (ID) straights. The impedance of an already existing ID vessel geometrically similar to the new one has been measured using the orbit bump method. The measurement results in comparison with analytical estimations and numerical simulations are discussed in this paper.

  5. Utilizing in Situ Directional Hyperpectral Measurements to Validate Reflectance and Bio- Indicator Simulations for Vegetation Canopies

    NASA Astrophysics Data System (ADS)

    Cheng, Y.; Middleton, E. M.; Zhang, Q.; Campbell, P. K.; Huemmrich, K. F.; Corp, L. A.; Kustas, W.

    2008-12-01

    Modeling directional reflectance in conjunction with in situ measurements provides an opportunity to quantitatively examine vegetation responses expressed under a variety of viewing geometries and illumination conditions and to mprove our understanding of physiology related to carbon exchange between plants and the atmosphere. Recent studies have demonstrated that light use efficiency can be remotely acquired by utilizing Photochemical Reflectance Index to account for physiological responses of foliage exposed to different illumination conditions. In this study, BRDF was simulated with three radiative transfer models, SAILh, rowMCRM and the FLAIR, and compared with in situ measurements for validations. During the summers of 2007 and 2008, field campaigns were conducted at experimental tree plots and a corn field maintained by the USDA BARC. Hyperspectral measurements (~1 nm) were acquired for sectors where illumination conditions for foliage were either sunlit, shaded, or mixed sunlit/shaded, based on the relative azimuth angle between the observer and the sun. The shaded foliage was associated with the darkspot of the BRDF while the sunlit canopy is situated in the hotspot. These measurements were utilized for model input and for validation, using the original spectra and vegetation indices derived from them. The agreements between model simulations and in situ measurements varied for the models used and varied among canopy illumination sectors and species. Simulations from the FLAIR model showed satisfactory results, especially for the shaded portions. For the corn field, the best agreements were simulations from rowMCRM. Simulations from SAILh were better for the sunlit canopy while reflectance generated with rowMCRM showed better agreement for both sunlit and shaded partitions. For the FLAIR model, the simulations showed better results in the visible spectrum while errors in SAILh- and rowMCRM- simulated reflectance were relatively uniform in the visible and

  6. An Evaluation of Monte Carlo Simulations of Neutron Multiplicity Measurements of Plutonium Metal

    SciTech Connect

    Mattingly, John; Miller, Eric; Solomon, Clell J. Jr.; Dennis, Ben; Meldrum, Amy; Clarke, Shaun; Pozzi, Sara

    2012-06-21

    In January 2009, Sandia National Laboratories conducted neutron multiplicity measurements of a polyethylene-reflected plutonium metal sphere. Over the past 3 years, those experiments have been collaboratively analyzed using Monte Carlo simulations conducted by University of Michigan (UM), Los Alamos National Laboratory (LANL), Sandia National Laboratories (SNL), and North Carolina State University (NCSU). Monte Carlo simulations of the experiments consistently overpredict the mean and variance of the measured neutron multiplicity distribution. This paper presents a sensitivity study conducted to evaluate the potential sources of the observed errors. MCNPX-PoliMi simulations of plutonium neutron multiplicity measurements exhibited systematic over-prediction of the neutron multiplicity distribution. The over-prediction tended to increase with increasing multiplication. MCNPX-PoliMi had previously been validated against only very low multiplication benchmarks. We conducted sensitivity studies to try to identify the cause(s) of the simulation errors; we eliminated the potential causes we identified, except for Pu-239 {bar {nu}}. A very small change (-1.1%) in the Pu-239 {bar {nu}} dramatically improved the accuracy of the MCNPX-PoliMi simulation for all 6 measurements. This observation is consistent with the trend observed in the bias exhibited by the MCNPX-PoliMi simulations: a very small error in {bar {nu}} is 'magnified' by increasing multiplication. We applied a scalar adjustment to Pu-239 {bar {nu}} (independent of neutron energy); an adjustment that depends on energy is probably more appropriate.

  7. Final Report - From Measurements to Models: Cross-Comparison of Measured and Simulated Behavioral States of the Atmosphere

    SciTech Connect

    Del Genio, Anthony D; Hoffman, Forrest M; Hargrove, Jr, William W

    2007-10-22

    The ARM sites and the ARM Mobile Facility (AMF) were constructed to make measurements of the atmosphere and radiation system in order to quantify deficiencies in the simulation of clouds within models and to make improvements in those models. While the measurement infrastructure of ARM is well-developed and a model parameterization testbed capability has been established, additional effort is needed to develop statistical techniques which permit the comparison of simulation output from atmospheric models with actual measurements. Our project establishes a new methodology for objectively comparing ARM measurements to the outputs of leading global climate models and reanalysis data. The quantitative basis for this comparison is provided by a statistical procedure which establishes an exhaustive set of mutually-exclusive, recurring states of the atmosphere from sets of multivariate atmospheric and cloud conditions, and then classifies multivariate measurements or simulation outputs into those states. Whether measurements and models classify the atmosphere into the same states at specific locations through time provides an unequivocal comparison result. Times and locations in both geographic and state space of model-measurement agreement and disagreement will suggest directions for the collection of additional measurements at existing sites, provide insight into the global representativeness of the current ARM sites (suggesting locations and times for use of the AMF), and provide a basis for improvement of models. Two different analyses were conducted: One, using the Parallel Climate Model, focused on an IPCC climate change scenario and clusters that characterize long-term changes in the hydrologic cycle. The other, using the GISS Model E GCM and the ARM Active Remotely Sensed Cloud Layers product, explored current climate cloud regimes in the Tropical West Pacific.

  8. Simulation method for interference fringe patterns in measuring gear tooth flanks by laser interferometry.

    PubMed

    Fang, Suping; Wang, Leijie; Komori, Masaharu; Kubo, Aizoh

    2010-11-20

    We present a ray-tracing-based method for simulation of interference fringe patterns (IFPs) for measuring gear tooth flanks with a two-path interferometer. This simulation method involves two steps. In the first step, the profile of an IFP is achieved by means of ray tracing within the object path of the interferometer. In the second step, the profile of an IFP is filled with interference fringes, according to a set of functions from an optical path length to a fringe gray level. To examine the correctness of this simulation method, simulations are performed for two spur involute gears, and the simulated IFPs are verified by experiments using the actual two-path interferometer built on an optical platform.

  9. Assessment of the neutron dose field around a biomedical cyclotron: FLUKA simulation and experimental measurements.

    PubMed

    Infantino, Angelo; Cicoria, Gianfranco; Lucconi, Giulia; Pancaldi, Davide; Vichi, Sara; Zagni, Federico; Mostacci, Domiziano; Marengo, Mario

    2016-12-01

    In the planning of a new cyclotron facility, an accurate knowledge of the radiation field around the accelerator is fundamental for the design of shielding, the protection of workers, the general public and the environment. Monte Carlo simulations can be very useful in this process, and their use is constantly increasing. However, few data have been published so far as regards the proper validation of Monte Carlo simulation against experimental measurements, particularly in the energy range of biomedical cyclotrons. In this work a detailed model of an existing installation of a GE PETtrace 16.5MeV cyclotron was developed using FLUKA. An extensive measurement campaign of the neutron ambient dose equivalent H(∗)(10) in marked positions around the cyclotron was conducted using a neutron rem-counter probe and CR39 neutron detectors. Data from a previous measurement campaign performed by our group using TLDs were also re-evaluated. The FLUKA model was then validated by comparing the results of high-statistics simulations with experimental data. In 10 out of 12 measurement locations, FLUKA simulations were in agreement within uncertainties with all the three different sets of experimental data; in the remaining 2 positions, the agreement was with 2/3 of the measurements. Our work allows to quantitatively validate our FLUKA simulation setup and confirms that Monte Carlo technique can produce accurate results in the energy range of biomedical cyclotrons. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  10. Simulation System for a Rebreathing Technique To Measure Multiple Cardiopulmonary Function Parameters

    PubMed Central

    Yilmaz, Cuneyt; Chance, William W.; Johnson, Robert L.; Hsia, Connie C. W.

    2009-01-01

    Background: We developed a simple method for simulating a rebreathing maneuver to test the accuracy of the apparatus for simultaneous measurement of lung volume, diffusing capacity of the lung for carbon monoxide (Dlco), diffusing capacity of the lung for nitric oxide (Dlno), and pulmonary blood flow (Q̇c). Methods: A test gas mixture containing 0.3% methane, 0.3% CO, 0.8% acetylene, 30% O2, and 40 ppm nitric oxide in balance of nitrogen was sequentially diluted with a rebreathing gas mixture containing 0.3% acetylene, 0.3% methane, and 21% O2 in balance of nitrogen in order to simulate the in vivo end-tidal disappearance of the test gas mixture. Simulation of one rebreathing maneuver consisted of at least four serial dilution steps with a performance time of < 5 min. Using this technique, we estimated functional residual capacity, Q̇c, Dlco, and Dlno at various flow rates and dilution ratios (0.95 to 4.04 L, 3.54 to 6.83 L/min, 7.27 to 15.12 mL/min/mm Hg, and 6.51 to 12.00 mL/min/mm Hg, respectively) and verified simulation results against nominal values. The same apparatus also could simulate a single-breath procedure. Results: Compared to nominal values, errors in measured values by rebreathing and single-breath Dlco simulation remained < 5% and 7%, respectively. Slopes of the correlations were close to 1.0 (within ± 5% and ± 6.4% in rebreathing and single-breath Dlco simulation studies, respectively). Conclusion: The results demonstrate the feasibility of this simulation method for standardizing the experimental measurements obtained by rebreathing and single-breath techniques. Incorporation of these simulation steps enhances the noninvasive assessment of cardiopulmonary function. PMID:19420198

  11. Myocardial physiology measurements using contrast enhanced dynamic computed tomography: simulation of beam hardening effect

    NASA Astrophysics Data System (ADS)

    Cao, Minsong; Stantz, Keith M.; Liang, Yun

    2006-03-01

    Initial animal study for quantifying myocardial physiology through contrast-enhanced dynamic x-ray CT suggested that beam hardening is one of the limiting factors for accurate regional physiology measurement. In this study, a series of simulations were performed to investigate its deterioration effects and two correction algorithms were adapted to evaluate for their efficiency in improving the measurements. The simulation tool consists of a module simulating data acquisition of a real polyenergetic scanner system and a heart phantom consisting of simple geometric objects representing ventricles and myocardium. Each phantom component was modeled with time-varying attenuation coefficients determined by ideal iodine contrast dynamic curves obtained from experimental data or simulation. A compartment model was used to generate the ideal myocardium contrast curve using physiological parameters consistent with measured values. Projection data of the phantom were simulated and reconstructed to produce a sequence of simulated CT images. Simulated contrast dynamic curves were fitted to the compartmental model and the resultant physiological parameters were compared with ideal values to estimate the errors induced by beam hardening artifacts. The simulations yielded similar deterioration patterns of contrast dynamic curves as observed in the initial study. Significant underestimation of left ventricle curves and corruption of regional myocardium curves result in systematic errors of regional perfusion up to approximately 24% and overestimates of fractional blood volume (f iv) up to 13%. The correction algorithms lead to significant improvement with errors of perfusion reduced to 7% and errors of f iv within 2% which shows promise for more robust myocardial physiology measurement.

  12. MSFC solar simulator test plane uniformity measurement. [for testing solar collectors

    NASA Technical Reports Server (NTRS)

    Griner, D. B.

    1976-01-01

    The equipment and procedure used to measure the test plane uniformity produced by the MSFC 405 lamp solar simulator array are described along with details of the computer program used to analyze the measurement data. The results of the first measurement show the uniformity not to be as good as expected. The best uniformity obtained had a standared deviation of 4 percent with peak-to-peak values of + or - 11 percent.

  13. Sensors as confidence building measures: A demonstration using a combat simulation

    SciTech Connect

    Warshawsky, A.S.; Spinosa, A.; Pimper, J.

    1994-06-01

    Numerous combat simulations have been developed and used to study the consequences of alternative force structures, analyze weapon performance, and train combat force commanders. These same simulations can, with minor modifications, be used to study a suite of arms control issues. To demonstrate this point, a modification of the LLNL Joint Conflict Model (JCM) was used to explain the utility of unattended ground sensors (UGS) as confidence building measures (CBMs) in the context of a regional arms control situation. It was shown that existing simulations (in particular, JCM) have the functionality necessary to easily and readily address regional arms control issues in a meaningful fashion.

  14. Measurement of metabolic responses to an orbital-extravehicular work-simulation exercise

    NASA Technical Reports Server (NTRS)

    Lantz, Renee; Webbon, Bruce

    1988-01-01

    This paper describes a new system designed to simulate orbital EVA work and measure metabolic responses to these space-work exercises. The system incorporates an experimental protocol, a controlled-atmosphere chamber, an EVA-work exercise device, the instrumentation, and a data acquisition system. Engineering issues associated with the design of the proposed system are discussed. This EVA-work simulating system can be used with various types of upper-body work, including task boards, rope pulling, and arm ergometry. Design diagrams and diagrams of various types of work simulation are included.

  15. Measurement of metabolic responses to an orbital-extravehicular work-simulation exercise

    NASA Technical Reports Server (NTRS)

    Lantz, Renee; Webbon, Bruce

    1988-01-01

    This paper describes a new system designed to simulate orbital EVA work and measure metabolic responses to these space-work exercises. The system incorporates an experimental protocol, a controlled-atmosphere chamber, an EVA-work exercise device, the instrumentation, and a data acquisition system. Engineering issues associated with the design of the proposed system are discussed. This EVA-work simulating system can be used with various types of upper-body work, including task boards, rope pulling, and arm ergometry. Design diagrams and diagrams of various types of work simulation are included.

  16. Errors in short circuit measurements due to spectral mismatch between sunlight and solar simulators

    NASA Technical Reports Server (NTRS)

    Curtis, H. B.

    1976-01-01

    Errors in short circuit current measurement were calculated for a variety of spectral mismatch conditions. The differences in spectral irradiance between terrestrial sunlight and three types of solar simulator were studied, as well as the differences in spectral response between three types of reference solar cells and various test cells. The simulators considered were a short arc xenon lamp AMO sunlight simulator, an ordinary quartz halogen lamp, and an ELH-type quartz halogen lamp. Three types of solar cells studied were a silicon cell, a cadmium sulfide cell and a gallium arsenide cell.

  17. Validation of measures from a thoracoscopic esophageal atresia/tracheoesophageal fistula repair simulator.

    PubMed

    Barsness, Katherine A; Rooney, Deborah M; Davis, Lauren M; Chin, Anthony C

    2014-01-01

    A validated high fidelity simulation model would provide a safe environment to teach thoracoscopic EA/TEF repair to novices. The study purpose was to evaluate validity evidence for performance measures on an EA/TEF simulator. IRB-exempt data were collected from 12 self-reported "novice" and 8 "experienced" pediatric surgeons. Participants evaluated the EA/TEF repair simulator using survey ratings that were analyzed for test content validity evidence. Additionally, deidentified operative performances were videotaped and independently rated by two surgeons using the Objective Structured Assessment for Technical Skills (OSATS) instrument. Novice and experienced OSATS were compared with p<.05 significant. Participants had high overall simulator ratings. Internal structure was supported by high interitem consistency (α=.95 and .96) and interrater agreement (ICC) [.52, .84] for OSATS ratings. Experienced surgeons performed at a significantly higher level than novices for all five primary and two supplemental OSATS items (p<.05). Favorable participant ratings indicate the simulator is relevant to clinical practice and valuable as a learning tool. Further, performance ratings can discriminate experienced and novice performances of EA/TEF repair. These findings support the use of the simulator for performance assessment, representing the first validated measures from a simulator intended for pediatric surgical training. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Design and Development of Virtual Reality Simulation for Teaching High-Risk Low-Volume Problem-Prone Office-Based Medical Emergencies

    ERIC Educational Resources Information Center

    Lemheney, Alexander J.

    2014-01-01

    Physicians' offices are not the usual place where emergencies occur; thus how staff remains prepared and current regarding medical emergencies presents an ongoing challenge for private practitioners. The very nature of low-volume, high-risk, and problem-prone medical emergencies is that they occur with such infrequency it is difficult for staff to…

  19. Design and Development of Virtual Reality Simulation for Teaching High-Risk Low-Volume Problem-Prone Office-Based Medical Emergencies

    ERIC Educational Resources Information Center

    Lemheney, Alexander J.

    2014-01-01

    Physicians' offices are not the usual place where emergencies occur; thus how staff remains prepared and current regarding medical emergencies presents an ongoing challenge for private practitioners. The very nature of low-volume, high-risk, and problem-prone medical emergencies is that they occur with such infrequency it is difficult for staff to…

  20. Temperature Dependent Measurement And Simulation Of Fresnel Lenses For Concentrating Photovoltaics

    NASA Astrophysics Data System (ADS)

    Hornung, Thorsten; Bachmaier, Andreas; Nitz, Peter; Gombert, Andreas

    2010-10-01

    Concentrating photovoltaics (CPV) require large areas of optical components that concentrate incident sunlight effectively onto a solar cell. Fresnel lenses are often used as primary optical component providing this concentration. When applied in the field, varying conditions during operation lead to variations in lens temperature which has a strong impact on the optical efficiency of the lenses. A setup for indoor characterization with the ability to heat lens plates allows for the assessment of the quality of Fresnel lenses by means of their irradiance profiles in the focal plane. To analyze the measured temperature dependency we simulate thermal deformations of the lens geometry with finite element method (FEM) tools and use the resulting lens geometry as an input to ray tracing simulations. We performed high accuracy measurements of the temperature and wavelength dependent refractive indices of relevant lens materials to obtain additional input data for computer simulations. A close match between computer simulations and measurements of the irradiance in the focal plane could be achieved, validating our simulation approach. This allows us to judge and optimize the temperature dependence of new lens designs before building and testing prototypes. The simulations themselves allow us to analyze and understand all superimposed effects in detail. The developed tools in combination with detailed solar resource data and knowledge of the CPV system will be the basis for future assessment of overall performance and further optimization of optics for CPV applications.

  1. Simulator and 2 tools: Validation of performance measures from a novel neurosurgery simulation model using the current Standards framework.

    PubMed

    Rooney, Deborah M; Tai, Bruce L; Sagher, Oren; Shih, Albert J; Wilkinson, David Andrew; Savastano, Luis E

    2016-09-01

    Ventriculostomy is a common neurosurgical procedure with a relatively steep learning curve. A low-cost, high-fidelity simulator paired with procedure-specific performance measures would provide a safe environment to teach ventriculostomy procedural skills. The same validated simulation model could also allow for assessment of trainees' proficiencies with measures that align with Accreditation Council for Graduate Medical Education milestones. This study extends previous work to evaluate validity evidence from the simulator, its newly developed performance assessment, the Ventricolostomy Procedural Assessment Tool, and the Objective Structured Assessment for Technical Skills. After Institutional Review Board exemption, performance data were collected from 11 novice and 3 expert neurosurgeons (n = 14). Participants self-reported their ability to perform tasks on the simulator using the Ventricolostomy Procedural Assessment Tool, an 11-item, step-wise instrument with 5-point rating scales ranging from 1 (unable to perform) to 5 (performs easily and smoothly). De-identified operative performances were videotaped and independently rated by 3 neurosurgeons, using the Ventricolostomy Procedural Assessment Tool and Objective Structured Assessment for Technical Skills. We evaluated multiple sources of validity evidence (2014 Standards) to examine psychometric quality of the measures and to test our assumption that the tools could discriminate between novice and expert performances adequately. We used a multifacet Rasch model and traditional indices, such as Cronbach alpha, intraclass correlation, and Wilcoxon signed-rank test estimates. Validity evidence relevant to test content and response processes was supported adequately. Evidence of internal structure was supported by high interitem consistency (n = 0.95) and inter-rater agreement for most Ventricolostomy Procedural Assessment Tool items (Intraclass correlation coefficient = [0.00, 0.91]) and all Objective

  2. Assessment of simulation fidelity using measurements of piloting technique in flight

    NASA Technical Reports Server (NTRS)

    Clement, W. F.; Cleveland, W. B.; Key, D. L.

    1984-01-01

    The U.S. Army and NASA joined together on a project to conduct a systematic investigation and validation of a ground based piloted simulation of the Army/Sikorsky UH-60A helicopter. Flight testing was an integral part of the validation effort. Nap-of-the-Earth (NOE) piloting tasks which were investigated included the bob-up, the hover turn, the dash/quickstop, the sidestep, the dolphin, and the slalom. Results from the simulation indicate that the pilot's NOE task performance in the simulator is noticeably and quantifiably degraded when compared with the task performance results generated in flight test. The results of the flight test and ground based simulation experiments support a unique rationale for the assessment of simulation fidelity: flight simulation fidelity should be judged quantitatively by measuring pilot's control strategy and technique as induced by the simulator. A quantitative comparison is offered between the piloting technique observed in a flight simulator and that observed in flight test for the same tasks performed by the same pilots.

  3. Assessment of simulation fidelity using measurements of piloting technique in flight

    NASA Technical Reports Server (NTRS)

    Clement, W. F.; Cleveland, W. B.; Key, D. L.

    1984-01-01

    The U.S. Army and NASA joined together on a project to conduct a systematic investigation and validation of a ground based piloted simulation of the Army/Sikorsky UH-60A helicopter. Flight testing was an integral part of the validation effort. Nap-of-the-Earth (NOE) piloting tasks which were investigated included the bob-up, the hover turn, the dash/quickstop, the sidestep, the dolphin, and the slalom. Results from the simulation indicate that the pilot's NOE task performance in the simulator is noticeably and quantifiably degraded when compared with the task performance results generated in flight test. The results of the flight test and ground based simulation experiments support a unique rationale for the assessment of simulation fidelity: flight simulation fidelity should be judged quantitatively by measuring pilot's control strategy and technique as induced by the simulator. A quantitative comparison is offered between the piloting technique observed in a flight simulator and that observed in flight test for the same tasks performed by the same pilots.

  4. Molecular dynamics simulations as a complement to nuclear magnetic resonance and X-ray diffraction measurements.

    PubMed

    Feller, Scott E

    2007-01-01

    Advances in the field of atomic-level membrane simulations are being driven by continued growth in computing power, improvements in the available potential energy functions for lipids, and new algorithms that implement advanced sampling techniques. These developments are allowing simulations to assess time- and length scales wherein meaningful comparisons with experimental measurements on macroscopic systems can be made. Such comparisons provide stringent tests of the simulation methodologies and force fields, and thus, advance the simulation field by pointing out shortcomings of the models. Extensive testing against available experimental data suggests that for many properties modern simulations have achieved a level of accuracy that provides substantial predictive power and can aid in the interpretation of experimental data. This combination of closely coupled laboratory experiments and molecular dynamics simulations holds great promise for the understanding of membrane systems. In the following, the molecular dynamics method is described with particular attention to those aspects critical for simulating membrane systems and to the calculation of experimental observables from the simulation trajectory.

  5. Simulations for the PHENIX Muon Piston Calorimeter Measurement of Transverse Energy

    NASA Astrophysics Data System (ADS)

    Zumberge, Christopher

    2012-10-01

    The PHENIX detector's Muon Piston Calorimeter measures the energies of photons (most of which are the products of pion decay) in the collisions of particles at the Relativistic Heavy Ion Collider (RHIC). The data acquired from the collisions of gold ions at √sNN=200 GeV will be used to measure the transverse energy over the kinematic acceptance of the detector. Corrections for the detector's hadronic response are needed to complete a measurement of the transverse energy and estimate systematic error. The PHENIX Integrated Simulation Application (PISA) is a software package that integrates both a GEANT3 simulation of the entire PHENIX detector and an event generator. In this case HIJING is being used as the event generator. Progress on the production of these simulations will be reported.

  6. 3D CFD simulations of trailing suction hopper dredger plume mixing: comparison with field measurements.

    PubMed

    de Wit, Lynyrd; Talmon, A M; van Rhee, C

    2014-11-15

    A 3D computational fluid dynamics (CFD) model is used to simulate mixing of an overflow plume within 400 m from a trailing suction hopper dredger (TSHD). The simulations are compared with new field measurements. It is the first time simulations of overflow dredging plumes are compared in such detail to field measurements this close to a TSHD. Seven cases with a large variety in overflow flux and plume characteristics are used. Measured maximum suspended sediment concentrations (SSC) vary between 30 and 500 mg/l and fluxes vary between 0.7% and 20% of the total overflow flux; the CFD model has, subject to the limitations of the field data, been shown to reproduce this in a satisfactory way. The model gives better understanding of important near field processes, which helps to assess the frequency, duration and intensity of stresses like turbidity and sedimentation needed to find the environmental impact of dredging projects. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Measurements and simulations of the cosmic-ray-induced neutron background

    NASA Astrophysics Data System (ADS)

    Becchetti, M. F.; Flaska, M.; Clarke, S. D.; Pozzi, S. A.

    2015-03-01

    The cosmic-ray-induced neutron background at ground level has been measured and simulated in conjunction with EJ-309 organic liquid scintillators with an approximate deposited energy range of 0.5-6 MeV. Specifically, the pulse height distributions, net neutron count rates, and angular dependences were obtained. The simulations were carried out using the Monte Carlo transport code MCNPX-PoliMi combined with the (Cosmic-Ray Shower Generator) CRY source subroutine that returns secondary particles produced by cosmic rays. A scaling formula from literature was also implemented in the simulation. The angular dependence of the neutron count rate was measured by collimating the liquid scintillator with polyethylene to attain 18° angular resolution from 0° downwards to 72° horizontally. The neutron count rate was measured to be 23.10±1.69 h-1 sr-1 at 0°, and 7.20±0.78 h-1 sr-1 at 72°. The simulations and measurements compare well and show similar cosine anisotropy for the angular distribution. The study thus shows that the neutron background response in detector systems can be efficiently and accurately simulated using the procedures described.

  8. A SOFTWARE TOOL TO COMPARE MEASURED AND SIMULATED BUILDING ENERGY PERFORMANCE DATA

    SciTech Connect

    Maile, Tobias; Bazjanac, Vladimir; O'Donnell, James; Garr, Matthew

    2011-11-01

    Building energy performance is often inadequate when compared to design goals. To link design goals to actual operation one can compare measured with simulated energy performance data. Our previously developed comparison approach is the Energy Performance Comparison Methodology (EPCM), which enables the identification of performance problems based on a comparison of measured and simulated performance data. In context of this method, we developed a software tool that provides graphing and data processing capabilities of the two performance data sets. The software tool called SEE IT (Stanford Energy Efficiency Information Tool) eliminates the need for manual generation of data plots and data reformatting. SEE IT makes the generation of time series, scatter and carpet plots independent of the source of data (measured or simulated) and provides a valuable tool for comparing measurements with simulation results. SEE IT also allows assigning data points on a predefined building object hierarchy and supports different versions of simulated performance data. This paper briefly introduces the EPCM, describes the SEE IT tool and illustrates its use in the context of a building case study.

  9. Infrared measurements and simulations of metal meshes in a focused beam

    SciTech Connect

    Stewart, K. P.; Möller, K. D.; Grebel, H.

    2014-02-07

    Infrared transmittance measurements of quasioptical filters are often restricted to a focused beam due to the optical design of the spectrometer. In contrast, numerical simulations assume an incident plane wave, which makes it difficult to compare theory with experimental data. We compare transmittance measurements with numerical simulations of square arrays of circular holes in 3-μm thick Cu sheets at angles of incidence from 0° to 20° for both s and p polarizations. These simple structures allow detailed tests of our electromagnetic simulation methods and show excellent agreement between theory and measurement. Measurements in a focused beam are accurately simulated by combining plane wave calculations over a range of angles that correspond to the focal ratio of the incident beam. Similar screens have been used as components of narrow bandpass filters for far-infrared astronomy, but these results show that the transmittance variations with angle of incidence and polarization limit their use to collimated beams at near normal incidence. The simulations are accurate enough to eliminate a costly trial-and-error approach to the design of more complex and useful quasioptical infrared filters and to predict their in-band performance and out-of-band blocking in focused beams.

  10. A measurement-based generalized source model for Monte Carlo dose simulations of CT scans

    NASA Astrophysics Data System (ADS)

    Ming, Xin; Feng, Yuanming; Liu, Ransheng; Yang, Chengwen; Zhou, Li; Zhai, Hezheng; Deng, Jun

    2017-03-01

    The goal of this study is to develop a generalized source model for accurate Monte Carlo dose simulations of CT scans based solely on the measurement data without a priori knowledge of scanner specifications. The proposed generalized source model consists of an extended circular source located at x-ray target level with its energy spectrum, source distribution and fluence distribution derived from a set of measurement data conveniently available in the clinic. Specifically, the central axis percent depth dose (PDD) curves measured in water and the cone output factors measured in air were used to derive the energy spectrum and the source distribution respectively with a Levenberg-Marquardt algorithm. The in-air film measurement of fan-beam dose profiles at fixed gantry was back-projected to generate the fluence distribution of the source model. A benchmarked Monte Carlo user code was used to simulate the dose distributions in water with the developed source model as beam input. The feasibility and accuracy of the proposed source model was tested on a GE LightSpeed and a Philips Brilliance Big Bore multi-detector CT (MDCT) scanners available in our clinic. In general, the Monte Carlo simulations of the PDDs in water and dose profiles along lateral and longitudinal directions agreed with the measurements within 4%/1 mm for both CT scanners. The absolute dose comparison using two CTDI phantoms (16 cm and 32 cm in diameters) indicated a better than 5% agreement between the Monte Carlo-simulated and the ion chamber-measured doses at a variety of locations for the two scanners. Overall, this study demonstrated that a generalized source model can be constructed based only on a set of measurement data and used for accurate Monte Carlo dose simulations of patients’ CT scans, which would facilitate patient-specific CT organ dose estimation and cancer risk management in the diagnostic and therapeutic radiology.

  11. Simulation

    NASA Technical Reports Server (NTRS)

    Foster, F.; Randle, R.

    1984-01-01

    The application of flight simulation in regional airline training programs is discussed. Specifically, the use of simulation in cockpit resources management training (CRMT) is investigated. The availability of simulation resources is explored and the simulator disadvantages and advantages are cited. Problems with simulator specification, procurement, validation and use that have plagued the major air carriers over several decades are addressed.

  12. Interface dosimetry: measurements and Monte Carlo simulations of low-energy photon beams

    NASA Astrophysics Data System (ADS)

    Das, Indra J.; Kassaee, Alireza; Verhaegen, Frank; Moskvin, Vadim P.

    2001-06-01

    A comparison of measured and simulated dose perturbations at high- Z interfaces with Monte Carlo (MC) codes, EGS4, MCNP4B , and PENELOPE, having varied algorithms is presented. The measured dose perturbations strongly depend on the chamber design and are always lower than the MC data. The EGS4 data are closer to the ion chamber values. The other two codes, MCNP4B and PENELOPE, predict relatively higher magnitude. The simulated secondary electron spectra from high- Z interfaces are different but cannot explain the differences in magnitude. It is concluded that MC codes capable of handling low-energy transport and better boundary crossing algorithms are needed for interface effects.

  13. Simulation of Feynman-alpha measurements from SILENE reactor using a discrete ordinates code

    SciTech Connect

    Humbert, P.; Mechitoua, B.; Verrey, B.

    2006-07-01

    In this paper we present the simulation of Feynman-{alpha} measurements from SILENE reactor using the discrete ordinates code PANDA. A 2-D cylindrical model of SILENE reactor is designed for computer simulations. Two methods are implemented for variance to mean calculation. In the first method we used the Feynman point reactor formula where the parameters (Diven factor, reactivity, detector efficiency and alpha eigenvalue) are obtained by 2-D PANDA calculations. In the second method the time dependent adjoint equations for the first two moments are solved. The calculated results are compared to the measurements. Both methods are in excellent agreement with the experimental data. (authors)

  14. Comparison of Analysis, Simulation, and Measurement of Wire-to-Wire Crosstalk. Part 2

    NASA Technical Reports Server (NTRS)

    Bradley, Arthur T.; Yavoich, Brian James; Hodson, Shane M.; Godley, Franklin

    2010-01-01

    In this investigation, we compare crosstalk analysis, simulation, and measurement results for electrically short configurations. Methods include hand calculations, PSPICE simulations, Microstripes transient field solver, and empirical measurement. In total, four representative physical configurations are examined, including a single wire over a ground plane, a twisted pair over a ground plane, generator plus receptor wires inside a cylindrical conduit, and a single receptor wire inside a cylindrical conduit. Part 1 addresses the first two cases, and Part 2 addresses the final two. Agreement between the analysis methods and test data is shown to be very good.

  15. Diffuse photon density wave measurements in comparison with the Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Kuzmin, V. L.; Neidrauer, M. T.; Diaz, D.; Zubkov, L. A.

    2015-03-01

    The Diffuse Photon Density Wave (DPDW) methodology is widely used in a number of biomedical applications. Here we present results of Monte Carlo simulations that employ an effective numerical procedure, based upon a description of radiative transfer in terms of the Bethe-Salpeter equation, and compare them with measurements from Intralipid aqueous solutions. In our scheme every act of scattering contributes to the signal. We find the Monte Carlo simulations and measurements to be in a very good agreement for a wide range of source -detector separations.

  16. Electric field simulation and measurement of a pulse line ion accelerator

    NASA Astrophysics Data System (ADS)

    Shen, Xiao-Kang; Zhang, Zi-Min; Cao, Shu-Chun; Zhao, Hong-Wei; Wang, Bo; Shen, Xiao-Li; Zhao, Quan-Tang; Liu, Ming; Jing, Yi

    2012-07-01

    An oil dielectric helical pulse line to demonstrate the principles of a Pulse Line Ion Accelerator (PLIA) has been designed and fabricated. The simulation of the axial electric field of an accelerator with CST code has been completed and the simulation results show complete agreement with the theoretical calculations. To fully understand the real value of the electric field excited from the helical line in PLIA, an optical electric integrated electric field measurement system was adopted. The measurement result shows that the real magnitude of axial electric field is smaller than that calculated, probably due to the actual pitch of the resister column which is much less than that of helix.

  17. Measurement of flowfield in a simulated solid-propellant ducted rocket combustor using laser Doppler velocimetry

    SciTech Connect

    Hsieh, W.H.; Yang, V.; Chuang, C.L.; Yang, A.S.; Cherng, D.L.

    1989-01-01

    A two-component LDV system was used to obtain detailed flow velocity and turbulence measurements in order to study the flow characteristics in a simulated solid-propellant ducted rocket combustor. The vortical structures near the dome region, the size of the recirculation zone, and the location of the reattachment point are all shown to be strongly affected by the jet momentum of both ram air and fuel streams. It is found that the turbulence intensity is anisotropic throughout the front portion of the simulated conbustor, and that the measured Reynolds stress conmponent distribution is well correlated with the local mean velocity vector distribution. 25 refs.

  18. Automated office blood pressure.

    PubMed

    Myers, Martin G; Godwin, Marshall

    2012-05-01

    Manual blood pressure (BP) is gradually disappearing from clinical practice with the mercury sphygmomanometer now considered to be an environmental hazard. Manual BP is also subject to measurement error on the part of the physician/nurse and patient-related anxiety which can result in poor quality BP measurements and office-induced (white coat) hypertension. Automated office (AO) BP with devices such as the BpTRU (BpTRU Medical Devices, Coquitlam, BC) has already replaced conventional manual BP in many primary care practices in Canada and has also attracted interest in other countries where research studies using AOBP have been undertaken. The basic principles of AOBP include multiple readings taken with a fully automated recorder with the patient resting alone in a quiet room. When these principles are followed, office-induced hypertension is eliminated and AOBP exhibits a much stronger correlation with the awake ambulatory BP as compared with routine manual BP measurements. Unlike routine manual BP, AOBP correlates as well with left ventricular mass as does the awake ambulatory BP. AOBP also simplifies the definition of hypertension in that the cut point for a normal AOBP (< 135/85 mm Hg) is the same as for the awake ambulatory BP and home BP. This article summarizes the currently available evidence supporting the use of AOBP in routine clinical practice and proposes an algorithm in which AOBP replaces manual BP for the diagnosis and management of hypertension.

  19. Flow visualizations, velocity measurements, and surface convection measurements in simulated 20. 8-cm Nova box amplifier cavities

    SciTech Connect

    Julien, J.L.; Molishever, E.L.

    1983-10-31

    Reported are fluid mechanics experiments performed in models of the 20.8-cm Nova amplifier lamp and disk cavities. Lamp cavity nitrogen flows are shown, by both flow visualization and velocity measurements, to be acceptably uniform and parallel to the flashlamps. In contrast, the nitrogen flows in the disk cavity are shown to be disordered. Even though disk cavity flows are disordered, the simplest of three proposed nitrogen introduction systems for the disk cavity was found to be acceptable based on convection measurements made at the surfaces of simulated laser disks.

  20. Mercury speciation measurements on a 10 MW{sub e} coal-fired boiler simulator

    SciTech Connect

    Evans, A.P.; Nevitt, K.D.

    1997-06-01

    The current trends towards deregulation of electric utilities, air toxic regulations and stringent fine particulate emissions reflect an increased need for coal-based research. In response, Babcock and Wilcox invested in the state-of-the-art 100 million Btu/hr (10 MW, equivalent) Clean Environment Development Facility (CEDF) located in Alliance, Ohio. The representative combustion conditions, flow patterns and residence times permit direct scale-up of CEDF test results to commercial boilers and pollution control devices. In cooperation with the U.S. Department of Energy and the Ohio Coal Development Office within the Ohio Office of Development, B&W is employing the CEDF to conduct a five-year project aimed at the development of practical, cost-effective strategies for reducing the emissions of hazardous air pollutants from coal-fired boilers. The project specifically targets the control of mercury, the trace element under close scrutiny by the EPA. Due to the various forms of mercury emissions from coal-fired boilers, accurate mercury speciation measurements are required to develop mercury control strategies. Current uncertainty in the accuracy and mercury speciation capability of mercury sampling methods led B&W to use both EPA Method 29 and the Ontario Hydro procedures to measure mercury emissions from CEDF pollution control devices. A comparison of the speciated mercury emissions is presented.

  1. Occupational exposure of personnel operating military radio equipment: measurements and simulation.

    PubMed

    Paljanos, Annamaria; Miclaus, Simona; Munteanu, Calin

    2015-09-01

    Technical literature provides numerous studies concerning radiofrequency exposure measurements for various radio communication devices, but there are few studies related to exposure of personnel operating military radio equipment. In order to evaluate exposure and identify cases when safety requirements are not entirely met, both measurements and simulations are needed for accurate results. Moreover, given the technical characteristics of the radio devices used in the military, personnel mainly operate in the near-field region so both measurements and simulation becomes more complex. Measurements were made in situ using a broadband personal exposimeter equipped with two isotropic probes for both electric and magnetic components of the field. The experiment was designed for three different operating frequencies of the same radio equipment, while simulations were made in FEKO software using hybrid numerical methods to solve complex electromagnetic field problems. The paper aims to discuss the comparative results of the measurements and simulation, as well as comparing them to reference levels specified in military or civilian radiofrequency exposure standards.

  2. Design of an Orthodontic Torque Simulator for Measurement of Bracket Deformation

    NASA Astrophysics Data System (ADS)

    Melenka, G. W.; Nobes, D. S.; Major, P. W.; Carey, J. P.

    2013-12-01

    The design and testing of an orthodontic torque simulator that reproduces the effect of archwire rotation on orthodontic brackets is described. This unique device is capable of simultaneously measuring the deformation and loads applied to an orthodontic bracket due to archwire rotation. Archwire rotation is used by orthodontists to correct the inclination of teeth within the mouth. This orthodontic torque simulator will provide knowledge of the deformation and loads applied to orthodontic bracket that will aide clinicians by describing the effect of archwire rotation on brackets. This will also impact that design on new archwirebracket systems by providing an assessment of performance. Deformation of the orthodontic bracket tie wings is measured using a digital image correlation process to measure elastic and plastic deformation. The magnitude of force and moments applied to the bracket though the archwire is also measured using a six-axis load cell. Initial tests have been performed on two orthodontic brackets of varying geometry to demonstrate the measurement capability of the orthodontic torque simulator. The demonstration experiment shows that a Damon Q bracket had a final plastic deformation after a single loading of 0.022 mm while the Speed bracket deformed 0.071 mm. This indicates that the Speed bracket plastically deforms 3.2 times more than the Damon Q bracket for similar magnitude of applied moment. The demonstration experiment demonstrates that bracket geometry affect the deformation of orthodontic brackets and this difference can be detected using the orthodontic torque simulator.

  3. Simulation of boreal black spruce chronosequences: Comparison to field measurements and model evaluation

    NASA Astrophysics Data System (ADS)

    Bond-Lamberty, Ben; Gower, Stith T.; Goulden, Michael L.; McMillan, Andrew

    2006-06-01

    This study used the Biome Biogeochemical Cycles (Biome-BGC) process model to simulate boreal forest dynamics, compared the results with a variety of measured carbon content and flux data from two boreal chronosequences in northern Manitoba, Canada, and examined how model output was affected by water and nitrogen limitations on simulated plant production and decomposition. Vascular and nonvascular plant growth were modeled over 151 years in well-drained and poorly drained forests, using as many site-specific model parameters as possible. Measured data included (1) leaf area and carbon content from site-specific allometry data, (2) aboveground and belowground net primary production from allometry and root cores, and (3) flux data, including biometry-based net ecosystem production and tower-based net ecosystem exchange. The simulation used three vegetation types or functional groups (evergreen needleaf trees, deciduous broadleaf trees, and bryophytes). Model output matched some of the observed data well, with net primary production, biomass, and net ecosystem production (NEP) values usually (50-80% of data) within the errors of observed values. Leaf area was generally underpredicted. In the simulation, nitrogen limitation increased with stand age, while soil anoxia limited vascular plant growth in the poorly drained simulation. NEP was most sensitive to climate variability in the poorly drained stands. Simulation results are discussed with respect to conceptual issues in, and parameterization of, the Biome-BGC model.

  4. Validation of the A&D UM-211 device for office blood pressure measurement according to the European Society of Hypertension International Protocol revision 2010.

    PubMed

    Fania, Claudio; Albertini, Federica; Palatini, Paolo

    2017-10-01

    The aim of this study was to define the accuracy of UM-211, an automated oscillometric device for office use coupled to several cuffs for different arm sizes, according to the International Protocol of the European Society of Hypertension. The validation was performed in 33 individuals. Their mean age was 59.6±12.9 years, systolic blood pressure (BP) was 144.3±21.5 mmHg (range: 96-184 mmHg), diastolic BP was 86.8±18.5 mmHg (range: 48-124 mmHg), and arm circumference was 30.2±4.3 cm (range: 23-39 cm). Four sequential readings were taken by observers 1 and 2 using a double-headed stethoscope and a mercury sphygmomanometer, whereas three BP readings were taken by the supervisor using the test instrument. The differences between the readings provided by the device and the mean observer measurements were calculated. Therefore, each device measurement was compared with the previous and the next mean observer measurement. The validation results fulfilled all the 2010 European Society of Hypertension revision Protocol criteria for the general population and passed all validation grades. On average, the device overestimated systolic BP by 1.7±2.4 mmHg and diastolic BP by 1.7±2.5 mmHg. These data show that the UM-211 device coupled to several cuffs for different ranges of arm circumference met the requirements for validation according to the International Protocol and can be recommended for clinical use in the adult population. However, these results mainly apply to the use of the 22-32 and the 31-45 cm cuffs.

  5. Measurement of the $B^-$ lifetime using a simulation free approach for trigger bias correction

    SciTech Connect

    Aaltonen, T.; Adelman, J.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.; Apresyan, A.; /Purdue U. /Waseda U.

    2010-04-01

    The collection of a large number of B hadron decays to hadronic final states at the CDF II detector is possible due to the presence of a trigger that selects events based on track impact parameters. However, the nature of the selection requirements of the trigger introduces a large bias in the observed proper decay time distribution. A lifetime measurement must correct for this bias and the conventional approach has been to use a Monte Carlo simulation. The leading sources of systematic uncertainty in the conventional approach are due to differences between the data and the Monte Carlo simulation. In this paper they present an analytic method for bias correction without using simulation, thereby removing any uncertainty between data and simulation. This method is presented in the form of a measurement of the lifetime of the B{sup -} using the mode B{sup -} {yields} D{sup 0}{pi}{sup -}. The B{sup -} lifetime is measured as {tau}{sub B{sup -}} = 1.663 {+-} 0.023 {+-} 0.015 ps, where the first uncertainty is statistical and the second systematic. This new method results in a smaller systematic uncertainty in comparison to methods that use simulation to correct for the trigger bias.

  6. Measurement of the B- lifetime using a simulation free approach for trigger bias correction

    NASA Astrophysics Data System (ADS)

    Aaltonen, T.; Adelman, J.; Álvarez González, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.; Apresyan, A.; Arisawa, T.; Artikov, A.; Asaadi, J.; Ashmanskas, W.; Attal, A.; Aurisano, A.; Azfar, F.; Badgett, W.; Barbaro-Galtieri, A.; Barnes, V. E.; Barnett, B. A.; Barria, P.; Bartos, P.; Bauer, G.; Beauchemin, P.-H.; Bedeschi, F.; Beecher, D.; Behari, S.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Beretvas, A.; Bhatti, A.; Binkley, M.; Bisello, D.; Bizjak, I.; Blair, R. E.; Blocker, C.; Blumenfeld, B.; Bocci, A.; Bodek, A.; Boisvert, V.; Bortoletto, D.; Boudreau, J.; Boveia, A.; Brau, B.; Bridgeman, A.; Brigliadori, L.; Bromberg, C.; Brubaker, E.; Budagov, J.; Budd, H. S.; Budd, S.; Burkett, K.; Busetto, G.; Bussey, P.; Buzatu, A.; Byrum, K. L.; Cabrera, S.; Calancha, C.; Camarda, S.; Campanelli, M.; Campbell, M.; Canelli, F.; Canepa, A.; Carls, B.; Carlsmith, D.; Carosi, R.; Carrillo, S.; Carron, S.; Casal, B.; Casarsa, M.; Castro, A.; Catastini, P.; Cauz, D.; Cavaliere, V.; Cavalli-Sforza, M.; Cerri, A.; Cerrito, L.; Chang, S. H.; Chen, Y. C.; Chertok, M.; Chiarelli, G.; Chlachidze, G.; Chlebana, F.; Cho, K.; Chokheli, D.; Chou, J. P.; Chung, K.; Chung, W. H.; Chung, Y. S.; Chwalek, T.; Ciobanu, C. I.; Ciocci, M. A.; Clark, A.; Clark, D.; Compostella, G.; Convery, M. E.; Conway, J.; Corbo, M.; Cordelli, M.; Cox, C. A.; Cox, D. J.; Crescioli, F.; Cuenca Almenar, C.; Cuevas, J.; Culbertson, R.; Cully, J. C.; Dagenhart, D.; D'Ascenzo, N.; Datta, M.; Davies, T.; de Barbaro, P.; de Cecco, S.; Deisher, A.; de Lorenzo, G.; Dell'Orso, M.; Deluca, C.; Demortier, L.; Deng, J.; Deninno, M.; D'Errico, M.; di Canto, A.; di Ruzza, B.; Dittmann, J. R.; D'Onofrio, M.; Donati, S.; Dong, P.; Dorigo, T.; Dube, S.; Ebina, K.; Elagin, A.; Erbacher, R.; Errede, D.; Errede, S.; Ershaidat, N.; Eusebi, R.; Fang, H. C.; Farrington, S.; Fedorko, W. T.; Feild, R. G.; Feindt, M.; Fernandez, J. P.; Ferrazza, C.; Field, R.; Flanagan, G.; Forrest, R.; Frank, M. J.; Franklin, M.; Freeman, J. C.; Furic, I.; Gallinaro, M.; Galyardt, J.; Garberson, F.; Garcia, J. E.; Garfinkel, A. F.; Garosi, P.; Gerberich, H.; Gerdes, D.; Gessler, A.; Giagu, S.; Giakoumopoulou, V.; Giannetti, P.; Gibson, K.; Gimmell, J. L.; Ginsburg, C. M.; Giokaris, N.; Giordani, M.; Giromini, P.; Giunta, M.; Giurgiu, G.; Glagolev, V.; Glenzinski, D.; Gold, M.; Goldschmidt, N.; Golossanov, A.; Gomez, G.; Gomez-Ceballos, G.; Goncharov, M.; González, O.; Gorelov, I.; Goshaw, A. T.; Goulianos, K.; Gresele, A.; Grinstein, S.; Grosso-Pilcher, C.; Group, R. C.; Grundler, U.; Guimaraes da Costa, J.; Gunay-Unalan, Z.; Haber, C.; Hahn, S. R.; Halkiadakis, E.; Han, B.-Y.; Han, J. Y.; Happacher, F.; Hara, K.; Hare, D.; Hare, M.; Harr, R. F.; Hartz, M.; Hatakeyama, K.; Hays, C.; Heck, M.; Heinrich, J.; Herndon, M.; Heuser, J.; Hewamanage, S.; Hidas, D.; Hill, C. S.; Hirschbuehl, D.; Hocker, A.; Hou, S.; Houlden, M.; Hsu, S.-C.; Hughes, R. E.; Huffman, B. T.; Hurwitz, M.; Husemann, U.; Hussein, M.; Huston, J.; Incandela, J.; Introzzi, G.; Iori, M.; Ivanov, A.; James, E.; Jang, D.; Jayatilaka, B.; Jeon, E. J.; Jha, M. K.; Jindariani, S.; Johnson, W.; Jones, M.; Joo, K. K.; Jun, S. Y.; Jung, J. E.; Junk, T. R.; Kamon, T.; Kar, D.; Karchin, P. E.; Kato, Y.; Kephart, R.; Ketchum, W.; Keung, J.; Khotilovich, V.; Kilminster, B.; Kim, D. H.; Kim, H. S.; Kim, H. W.; Kim, J. E.; Kim, M. J.; Kim, S. B.; Kim, S. H.; Kim, Y. K.; Kimura, N.; Kirsch, L.; Klimenko, S.; Kondo, K.; Kong, D. J.; Konigsberg, J.; Korytov, A.; Kotwal, A. V.; Kreps, M.; Kroll, J.; Krop, D.; Krumnack, N.; Kruse, M.; Krutelyov, V.; Kuhr, T.; Kulkarni, N. P.; Kurata, M.; Kwang, S.; Laasanen, A. T.; Lami, S.; Lammel, S.; Lancaster, M.; Lander, R. L.; Lannon, K.; Lath, A.; Latino, G.; Lazzizzera, I.; Lecompte, T.; Lee, E.; Lee, H. S.; Lee, J. S.; Lee, S. W.; Leone, S.; Lewis, J. D.; Lin, C.-J.; Linacre, J.; Lindgren, M.; Lipeles, E.; Lister, A.; Litvintsev, D. O.; Liu, C.; Liu, T.; Lockyer, N. S.; Loginov, A.; Lovas, L.; Lucchesi, D.; Lueck, J.; Lujan, P.; Lukens, P.; Lungu, G.; Lyons, L.; Lys, J.; Lysak, R.; MacQueen, D.; Madrak, R.; Maeshima, K.; Makhoul, K.; Maksimovic, P.; Malde, S.; Malik, S.; Manca, G.; Manousakis-Katsikakis, A.; Margaroli, F.; Marino, C.; Marino, C. P.; Martin, A.; Martin, V.; Martínez, M.; Martínez-Ballarín, R.; Mastrandrea, P.; Mathis, M.; Mattson, M. E.; Mazzanti, P.; McFarland, K. S.; McIntyre, P.; McNulty, R.; Mehta, A.; Mehtala, P.; Menzione, A.; Mesropian, C.; Miao, T.; Mietlicki, D.; Miladinovic, N.; Miller, R.; Mills, C.; Milnik, M.; Mitra, A.; Mitselmakher, G.; Miyake, H.; Moed, S.; Moggi, N.; Mondragon, M. N.; Moon, C. S.; Moore, R.; Morello, M. J.; Morlock, J.; Movilla Fernandez, P.; Mülmenstädt, J.; Mukherjee, A.; Muller, Th.; Murat, P.; Mussini, M.; Nachtman, J.; Nagai, Y.; Naganoma, J.; Nakamura, K.; Nakano, I.; Napier, A.; Nett, J.; Neu, C.; Neubauer, M. S.; Neubauer, S.; Nielsen, J.; Nodulman, L.; Norman, M.; Norniella, O.; Nurse, E.; Oakes, L.; Oh, S. H.; Oh, Y. D.; Oksuzian, I.; Okusawa, T.; Orava, R.; Osterberg, K.; Pagan Griso, S.; Pagliarone, C.; Palencia, E.; Papadimitriou, V.; Papaikonomou, A.; Paramanov, A. A.; Parks, B.; Pashapour, S.; Patrick, J.; Pauletta, G.; Paulini, M.; Paus, C.; Peiffer, T.; Pellett, D. E.; Penzo, A.; Phillips, T. J.; Piacentino, G.; Pianori, E.; Pinera, L.; Pitts, K.; Plager, C.; Pondrom, L.; Potamianos, K.; Poukhov, O.; Pounder, N. L.; Prokoshin, F.; Pronko, A.; Ptohos, F.; Pueschel, E.; Punzi, G.; Pursley, J.; Rademacker, J.; Rahaman, A.; Ramakrishnan, V.; Ranjan, N.; Redondo, I.; Renton, P.; Renz, M.; Rescigno, M.; Richter, S.; Rimondi, F.; Ristori, L.; Robson, A.; Rodrigo, T.; Rodriguez, T.; Rogers, E.; Rolli, S.; Roser, R.; Rossi, M.; Rossin, R.; Roy, P.; Ruiz, A.; Russ, J.; Rusu, V.; Rutherford, B.; Saarikko, H.; Safonov, A.; Sakumoto, W. K.; Santi, L.; Sartori, L.; Sato, K.; Saveliev, V.; Savoy-Navarro, A.; Schlabach, P.; Schmidt, A.; Schmidt, E. E.; Schmidt, M. A.; Schmidt, M. P.; Schmitt, M.; Schwarz, T.; Scodellaro, L.; Scribano, A.; Scuri, F.; Sedov, A.; Seidel, S.; Seiya, Y.; Semenov, A.; Sexton-Kennedy, L.; Sforza, F.; Sfyrla, A.; Shalhout, S. Z.; Shears, T.; Shepard, P. F.; Shimojima, M.; Shiraishi, S.; Shochet, M.; Shon, Y.; Shreyber, I.; Simonenko, A.; Sinervo, P.; Sisakyan, A.; Slaughter, A. J.; Slaunwhite, J.; Sliwa, K.; Smith, J. R.; Snider, F. D.; Snihur, R.; Soha, A.; Somalwar, S.; Sorin, V.; Squillacioti, P.; Stanitzki, M.; St. Denis, R.; Stelzer, B.; Stelzer-Chilton, O.; Stentz, D.; Strologas, J.; Strycker, G. L.; Suh, J. S.; Sukhanov, A.; Suslov, I.; Taffard, A.; Takashima, R.; Takeuchi, Y.; Tanaka, R.; Tang, J.; Tecchio, M.; Teng, P. K.; Thom, J.; Thome, J.; Thompson, G. A.; Thomson, E.; Tipton, P.; Ttito-Guzmán, P.; Tkaczyk, S.; Toback, D.; Tokar, S.; Tollefson, K.; Tomura, T.; Tonelli, D.; Torre, S.; Torretta, D.; Totaro, P.; Trovato, M.; Tsai, S.-Y.; Tu, Y.; Turini, N.; Ukegawa, F.; Uozumi, S.; van Remortel, N.; Varganov, A.; Vataga, E.; Vázquez, F.; Velev, G.; Vellidis, C.; Vidal, M.; Vila, I.; Vilar, R.; Vogel, M.; Volobouev, I.; Volpi, G.; Wagner, P.; Wagner, R. G.; Wagner, R. L.; Wagner, W.; Wagner-Kuhr, J.; Wakisaka, T.; Wallny, R.; Wang, S. M.; Warburton, A.; Waters, D.; Weinberger, M.; Weinelt, J.; Wester, W. C., III; Whitehouse, B.; Whiteson, D.; Wicklund, A. B.; Wicklund, E.; Wilbur, S.; Williams, G.; Williams, H. H.; Wilson, P.; Winer, B. L.; Wittich, P.; Wolbers, S.; Wolfe, C.; Wolfe, H.; Wright, T.; Wu, X.; Würthwein, F.; Yagil, A.; Yamamoto, K.; Yamaoka, J.; Yang, U. K.; Yang, Y. C.; Yao, W. M.; Yeh, G. P.; Yi, K.; Yoh, J.; Yorita, K.; Yoshida, T.; Yu, G. B.; Yu, I.; Yu, S. S.; Yun, J. C.; Zanetti, A.; Zeng, Y.; Zhang, X.; Zheng, Y.; Zucchelli, S.

    2011-02-01

    The collection of a large number of B-hadron decays to hadronic final states at the CDF II Detector is possible due to the presence of a trigger that selects events based on track impact parameters. However, the nature of the selection requirements of the trigger introduces a large bias in the observed proper-decay-time distribution. A lifetime measurement must correct for this bias, and the conventional approach has been to use a Monte Carlo simulation. The leading sources of systematic uncertainty in the conventional approach are due to differences between the data and the Monte Carlo simulation. In this paper, we present an analytic method for bias correction without using simulation, thereby removing any uncertainty due to the differences between data and simulation. This method is presented in the form of a measurement of the lifetime of the B- using the mode B-→D0π-. The B- lifetime is measured as τB-=1.663±0.023±0.015ps, where the first uncertainty is statistical and the second systematic. This new method results in a smaller systematic uncertainty in comparison to methods that use simulation to correct for the trigger bias.

  7. Integrated P1 Hohlraum/Capsule Simulations with Comparison to Neutron and X-Ray Measurements

    NASA Astrophysics Data System (ADS)

    Eder, D. C.; Spears, B. K.; Town, R. P.; Jones, O. S.; Munro, D. H.; Peterson, J. L.; Ma, T.; Pak, A. K.; Benedetti, L. R.; Hatchett, S. P.; Knauer, J. P.; MacKinnon, A. J.; Yeamans, C. B.; McNaney, J. M.; Casey, D. T.; NIF Team

    2013-10-01

    We discuss integrated hohlraum/capsule simulations that drive a DT symcap capsule downward in a NIF experiment by increasing/decreasing the peak power in the upper/lower laser beams by 8%. This laser asymmetry results in a radiation drive P1/P0 at the capsule ablation surface of 2% and a downward capsule velocity of 125 microns/ns. The simulation shows small (<1%) changes in the P2 and P4 moments of the x-ray self-emission as compared to a simulation with no laser asymmetry. The calculated reduction in yield due to the induced P1 is 20%. Simulations for DT layered capsules for comparable velocities have yields an order of magnitude lower than simulations with stationary capsules. The velocity is measured by comparing the arrival times of DD and DT neutrons at detectors located at different locations. Preliminary data from a recent shot gives a downward velocity of order 100 microns/ns consistent with simulations. We also compare pre- and post-shot simulations with x-ray images at different energies. The ability to correct for capsule velocity, e.g., due to different upper/lower crossbeam transfer energies, is another tool in the quest for ignition. This work performed under the auspices of the U.S. Department of Energy by LLNL under Contract DE-AC52-07NA27344. LLNL-ABS-640047.

  8. Measurement of effective sheath width around the cutoff probe based on electromagnetic simulation

    SciTech Connect

    Kim, D. W.; Oh, W. Y. E-mail: woh1@kaist.ac.kr; You, S. J. E-mail: woh1@kaist.ac.kr; Kim, J. H.; Chang, H. Y.; Yoon, J.-S.

    2016-05-15

    We inferred the effective sheath width using the cutoff probe and incorporating a full-wave three-dimensional electromagnetic (EM) simulation. The EM simulation reproduced the experimentally obtained plasma-sheath resonance (PSR) on the microwave transmission (S{sub 21}) spectrum well. The PSR frequency has a one-to-one correspondence with the width of the vacuum layer assumed to be the effective sheath in the EM simulation model. The sheath width was estimated by matching the S{sub 21} spectra of the experiment and the EM simulation for different widths of the sheath. We found that the inferred sheath widths quantitatively and qualitatively agree with the sheath width measured by incorporating an equivalent circuit model. These results demonstrate the excellent potential of the cutoff probe for inferring the effective sheath width from its experimental spectrum data.

  9. Evaluation of ride quality measurement procedures by subjective experiments using simulators

    NASA Technical Reports Server (NTRS)

    Klauder, L. T., Jr.; Clevenson, S. A.

    1975-01-01

    Since ride quality is, by definition, a matter of passenger response, there is need for a qualification procedure (QP) for establishing the degree to which any particular ride quality measurement procedure (RQMP) does correlate with passenger responses. Once established, such a QP will provide very useful guidance for optimal adjustment of the various parameters which any given RQMP contains. A QP is proposed based on use of a ride motion simulator and on test subject responses to recordings of actual vehicle motions. Test subject responses are used to determine simulator gain settings for the individual recordings such as to make all of the simulated rides equally uncomfortable to the test subjects. Simulator platform accelerations vs. time are recorded with each ride at its equal discomfort gain setting. The equal discomfort platform acceleration recordings are then digitzed.

  10. Optimized goniometer for determination of the scattering phase function of suspended particles: simulations and measurements

    NASA Astrophysics Data System (ADS)

    Foschum, Florian; Kienle, Alwin

    2013-08-01

    We present simulations and measurements with an optimized goniometer for determination of the scattering phase function of suspended particles. We applied the Monte Carlo method, using a radially layered cylindrical geometry and mismatched boundary conditions, in order to investigate the influence of reflections caused by the interfaces of the glass cuvette and the scatterer concentration on the accurate determination of the scattering phase function. Based on these simulations we built an apparatus which allows direct measurement of the phase function from ϑ=7 deg to ϑ=172 deg without any need for correction algorithms. Goniometric measurements on polystyrene and SiO2 spheres proved this concept. Using the validated goniometer, we measured the phase function of yeast cells, demonstrating the improvement of the new system compared to standard goniometers. Furthermore, the scattering phase function of different fat emulsions, like Intralipid, was determined precisely.

  11. Rain simulator as a standardized laboratory measurement of soil structural stability

    NASA Astrophysics Data System (ADS)

    Iglesias, Luz; Cancelo González, Javier; Benito, Elena; Álvarez, Manuel; Barral, Maria Teresa; Díaz-Fierros, Francisco

    2010-05-01

    Rainfall simulations are used since the 30's by scientist and technicians to study the soil erosion and soil hydrology. The basis of the rainfall simulation is that can reproduce the natural soil degradation processes, more accurately than the traditional methods used for the determination of structural stability. A rainfall simulator was built in 2006 based on those made by Guitián and Méndez (1961), and Morin (1967), to obtain standardized laboratory measurements of soil structural stability and a final implementation were made in the rainfall simulator to incorporate a intermittent fan-like water yet system with four sieves of 250 micrometres where the soil samples can be placed, and allow the simultaneous measurement of soil losses in the samples. Data obtained in the rainfall simulator, using different soils of the study basins, are related with the Ig Henin index and the results of the Emerson structural stability test. At the same time with the laboratory test, 10 water sampling surveys were carried out during the hydrological years 2004/05 and 2005/06, in two basins located in the humid region of NW Spain belonging to the Anllons River basin, one of the main basins of Galicia-Costa, that has been subject of detailed hydrological studies since 2000 (Rial, M., 2007 and Devesa, R., 2009) and had continuous records of streamflow. The selected subbasins have 57,62 and 50,05 square kilometres respectively, and presents significative geological differences; being one of them formed, mainly, by schists and a lower area with granites and, the other one formed mainly by gabbros. The suspended sediments in the samples were separated by centrifugation and weighted in the laboratory to study the possible relationship between soil losses in the rainfall simulations and the sediment fluxes in the river. The analysis revealed a good relationship between the sediments delivery to the streams and soil losses measured in the rainfall simulations.

  12. Experimental measurement of microwave ablation heating pattern and comparison to computer simulations.

    PubMed

    Deshazer, Garron; Prakash, Punit; Merck, Derek; Haemmerich, Dieter

    2017-02-01

    For computational models of microwave ablation (MWA), knowledge of the antenna design is necessary, but the proprietary design of clinical applicators is often unknown. We characterised the specific absorption rate (SAR) during MWA experimentally and compared to a multi-physics simulation. An infrared (IR) camera was used to measure SAR during MWA within a split ex vivo liver model. Perseon Medical's short-tip (ST) or long-tip (LT) MWA antenna were placed on top of a tissue sample (n = 6), and microwave power (15 W) was applied for 6 min, while intermittently interrupting power. Tissue surface temperature was recorded via IR camera (3.3 fps, 320 × 240 resolution). SAR was calculated intermittently based on temperature slope before and after power interruption. Temperature and SAR data were compared to simulation results. Experimentally measured SAR changed considerably once tissue temperatures exceeded 100 °C, contrary to simulation results. The ablation zone diameters were 1.28 cm and 1.30 ± 0.03 cm (transverse), and 2.10 cm and 2.66 ± -0.22 cm (axial), for simulation and experiment, respectively. The average difference in temperature between the simulation and experiment were 5.6 °C (ST) and 6.2 °C (LT). Dice coefficients for 1000 W/kg SAR iso-contour were 0.74 ± 0.01 (ST) and 0.77 (± 0.03) (LT), suggesting good agreement of SAR contours. We experimentally demonstrated changes in SAR during MWA ablation, which were not present in simulation, suggesting inaccuracies in dielectric properties. The measured SAR may be used in simplified computer simulations to predict tissue temperature when the antenna geometry is unknown.

  13. Assessment of environmental and nondestructive earthquake effects on modal parameters of an office building based on long-term vibration measurements

    NASA Astrophysics Data System (ADS)

    Wu, Wen-Hwa; Wang, Sheng-Wei; Chen, Chien-Chou; Lai, Gwolong

    2017-05-01

    Identification for the modal parameters of an instrumented office building using ambient vibration measurements is conducted in this study based on a recently developed stochastic subspace identification methodology equipped with an alternative stabilization diagram and a hierarchical sifting process. The identified results are then deliberately examined to recognize the dynamic features for quite a few dominant modes of this building structure including three pairs of closely-spaced modes. Making use of the collected three-month data including three seismic events, the analyzed results show that the root-mean-square vibration response is directly related to the wind speed and indirectly related to the air temperature under a specific condition. More importantly, it is discovered that the root-mean-square response is the dominant factor to induce the variation of modal parameters. Except for the torsional modes, all the other modal frequencies are highly correlated with the root-mean-square acceleration in a negative manner and the corresponding damping ratios also clearly display a positive correlation. Another crucial observation from this assessment is that the percentages of frequency variation in three months for most of the identified modes go beyond 10%. The effects of three nondestructive earthquakes are further traced to observe the tendencies of reducing the modal frequencies and raising the damping ratios, both with a variation level possibly increasing with the seismic intensity. But different from the effects of environmental factors, the changes in modal parameters caused by nondestructive earthquakes will vanish right after the seismic events.

  14. Measuring the Benefits of Public Chargers and Improving Infrastructure Deployments Using Advanced Simulation Tools: Preprint

    SciTech Connect

    Wood, Eric; Neubauer. Jeremy; Burton, Evan

    2015-02-01

    With support from the U.S. Department of Energy's Vehicle Technologies Office, the National Renewable Energy Laboratory developed BLAST-V -- the Battery Lifetime Analysis and Simulation Tool for Vehicles. The addition of high-resolution spatial-temporal travel histories enables BLAST-V to investigate user-defined infrastructure rollouts of publically accessible charging infrastructure, as well as quantify impacts on vehicle and station owners in terms of improved vehicle utility and station throughput. This paper presents simulation outputs from BLAST-V that quantify the utility improvements of multiple distinct rollouts of publically available Level 2 electric vehicle supply equipment (EVSE) in the Seattle, Washington, metropolitan area. Publically available data on existing Level 2 EVSE are also used as an input to BLAST-V. The resulting vehicle utility is compared to a number of mock rollout scenarios. Discussion focuses on the estimated number of Level 2 stations necessary to substantially increase vehicle utility and how stations can be strategically sited to maximize their potential benefit to prospective electric vehicle owners.

  15. Large-Eddy Simulations and Lidar Measurements of Vortex-Pair Breakup in Aircraft Wakes

    NASA Technical Reports Server (NTRS)

    Lewellen, D. C.; Lewellen, W. S.; Poole, L. R.; DeCoursey, R. J.; Hansen, G. M.; Hostetler, C. A.; Kent, G. S.

    1998-01-01

    Results of large-eddy simulations of an aircraft wake are compared with results from ground-based lidar measurements made at NASA Langley Research Center during the Subsonic Assessment Near-Field Interaction Flight Experiment field tests. Brief reviews of the design of the field test for obtaining the evolution of wake dispersion behind a Boeing 737 and of the model developed for simulating such wakes are given. Both the measurements and the simulations concentrate on the period from a few seconds to a few minutes after the wake is generated, during which the essentially two-dimensional vortex pair is broken up into a variety of three-dimensional eddies. The model and experiment show similar distinctive breakup eddies induced by the mutual interactions of the vortices, after perturbation by the atmospheric motions.

  16. Large-Eddy Simulations and Lidar Measurements of Vortex-Pair Breakup in Aircraft Wakes

    NASA Technical Reports Server (NTRS)

    Lewellen, D. C.; Lewellen, W. S.; Poole, L. R.; DeCoursey, R. J.; Hansen, G. M.; Hostetler, C. A.; Kent, G. S.

    1998-01-01

    Results of large-eddy simulations of an aircraft wake are compared with results from ground-based lidar measurements made at NASA Langley Research Center during the Subsonic Assessment Near-Field Interaction Flight Experiment field tests. Brief reviews of the design of the field test for obtaining the evolution of wake dispersion behind a Boeing 737 and of the model developed for simulating such wakes are given. Both the measurements and the simulations concentrate on the period from a few seconds to a few minutes after the wake is generated, during which the essentially two-dimensional vortex pair is broken up into a variety of three-dimensional eddies. The model and experiment show similar distinctive breakup eddies induced by the mutual interactions of the vortices, after perturbation by the atmospheric motions.

  17. SIMULATIONS AND MEASUREMENTS OF A HEAVILY HOM-DAMPED MULTI-CELL SRF CAVITY

    SciTech Connect

    Haipeng Wang; Robert Rimmer; Frank Marhauser

    2007-07-02

    After an initial cavity shape optimization [1] and cryomodule development [2] for an Ampere-class FEL ERL, we have simulated a complete 5-cell high-current (HC) cavity structure with six waveguide (WG) couplers for Higher Order Mode (HOM) damping and fundamental power coupling. The time-domain wakefield simulations of the MAFIA codes have been used to calculate the cavities broadband HOM impedance spectrum. Microwave Studio (MWS) has also been used to evaluate the external Q of the fundamental power coupler (FPC) and the R/Qs of the HOMs. A half scale 1497MHz single-cell model cavity and a 5-cell copper cavity including dummy HOM WG loads were fabricated to bench measure and confirm the design performance. Details of the multi-beam wakefield simulations, the HOM damping measurements and multi-peak data fitting analysis techniques are presented.

  18. Indoor characterization at production scale: 200 kWp of CPV solar simulator measurements

    NASA Astrophysics Data System (ADS)

    Ferrer, Juan Pablo; Martínez, María; Trujillo, Pablo; Rubio, Francisca; Askins, Steve; Domínguez, César; Herrero, Rebeca; Sala, Gabriel

    2012-10-01

    In order to complement ISFOC's characterization capabilities, a Helios 3198 CPV Solar Simulator was installed in summer 2010. This Solar Simulator, based on a parabolic mirror and a high-intensity, small area Xenon flash lamp was developed by the Instituto de Energía Solar in Madrid [1] and is manufactured and distributed by Soldaduras Avanzadas [2]. This simulator is used not only for R&D purposes, but as a quality control tool for incoming modules that are to be installed in ISFOC's CPV plants. In this paper we will discuss the results of recent measurements of close to 5000 modules, the entire production of modules corresponding to a small CPV power plant (200 kWp). We scrutinize the resultant data for signs of drift in the measurements, and analyze the light quality before and after, to check for changes in spectrum or spatial uniformity.

  19. Comparisons between GRNTRN simulations and beam measurements of proton lateral broadening distributions

    NASA Astrophysics Data System (ADS)

    Mertens, Christopher; Moyers, Michael; Walker, Steven; Tweed, John

    Recent developments in NASA's High Charge and Energy Transport (HZETRN) code have included lateral broadening of primary ion beams due to small-angle multiple Coulomb scattering, and coupling of the ion-nuclear scattering interactions with energy loss and straggling. The new version of HZETRN based on Green function methods, GRNTRN, is suitable for modeling transport with both space environment and laboratory boundary conditions. Multiple scattering processes are a necessary extension to GRNTRN in order to accurately model ion beam experiments, to simulate the physical and biological-effective radiation dose, and to develop new methods and strategies for light ion radiation therapy. In this paper we compare GRNTRN simulations of proton lateral scattering distributions with beam measurements taken at Loma Linda Medical University. The simulated and measured lateral proton distributions will be compared for a 250 MeV proton beam on aluminum, polyethylene, polystyrene, bone, iron, and lead target materials.

  20. Measurement and Simulation of Signal Fluctuations Caused by Propagation through Trees

    NASA Technical Reports Server (NTRS)

    Durden, Stephen L.; Klein, Jeffrey D.; Zebker, Howard A.

    1993-01-01

    We present measured magnitude and phase fluctuations of UHF, L band, and C band signals that were transmitted from the ground through a forest canopy to an airborne radar. We find that the measured fluctuations are similar to those calculated by a simple Monte Carlo simulation. Both observed and calculated RMS fluctuations are typically several decibels in magnitude and tens of degrees in phase at all three frequencies.

  1. Energy Performance Measurement and Simulation Modeling of Tactical Soft-Wall Shelters

    DTIC Science & Technology

    2015-07-01

    Basic for Applications ( VBA ). The objective function was the root mean square (RMS) errors between modeled and measured heating load and the modeled ...ER D C/ CE RL T R- 15 -1 3 Operational Energy Capabilities Improvement Energy Performance Measurement and Simulation Modeling of...and Ashok Kumar July 2015 Approved for public release; distribution is unlimited. HDT AirBeam Model 2032 Utilis Model TM60 ERDC-CERL

  2. EGS_cbct: Simulation of a fan beam CT and RMI phantom for measured HU verification.

    PubMed

    van Eeden, Dete; du Plessis, Freek

    2016-10-01

    A mathematical 3D model of an existing computed tomography (CT) scanner was created and used in the EGSnrc-based BEAMnrc and egs_cbct Monte Carlo codes. Simulated transmission dose profiles of a RMI-465 phantom were analysed to verify Hounsfield numbers against measured data obtained from the CT scanner. The modelled CT unit is based on the design of a Toshiba Aquilion 16 LB CT scanner. As a first step, BEAMnrc simulated the X-ray tube, filters, and secondary collimation to obtain phase space data of the X-ray beam. A bowtie filter was included to create a more uniform beam intensity and to remove the beam hardening effects. In a second step the Interactive Data Language (IDL) code was used to build an EGSPHANT file that contained the RMI phantom which was used in egs_cbct simulations. After simulation a series of profiles were sampled from the detector model and the Feldkamp-Davis-Kress (FDK) algorithm was used to reconstruct transversal images. The results were tested against measured data obtained from CT scans. The egs_cbct code can be used for the simulation of a fan beam CT unit. The calculated bowtie filter ensured a uniform flux on the detectors. Good correlation between measured and simulated CT numbers was obtained. In principle, Monte Carlo codes such as egs_cbct can model a fan beam CT unit. After reconstruction, the images contained Hounsfield values comparable to measured data. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  3. Life Span as the Measure of Performance and Learning in a Business Gaming Simulation

    ERIC Educational Resources Information Center

    Thavikulwat, Precha

    2012-01-01

    This study applies the learning curve method of measuring learning to participants of a computer-assisted business gaming simulation that includes a multiple-life-cycle feature. The study involved 249 participants. It verified the workability of the feature and estimated the participants' rate of learning at 17.4% for every doubling of experience.…

  4. Delayed Neutron & Gamma Measurements of Special Nuclear Materials and MCNP6 Simulations

    SciTech Connect

    Sellers, Madison; Goorley, John T.; Corcoran, E. C.; Kelly, D. G.

    2014-01-21

    Measurements of DG emissions from 0.8 – 1.6 MeV were compared to MCNP6 simulations. Several discrepancies were resolved with use of ENDFVII.1 decay data. Furthermore, MCNP6 was executable with delayed bin fix resolved several line intensity discrepancies.

  5. Scale issues in soil hydrology related to measurement and simulation: A case study in Colorado

    USDA-ARS?s Scientific Manuscript database

    State variables, such as soil water content (SWC), are typically measured or inferred at very small scales while being simulated at larger scales relevant to spatial management or hillslope areas. Thus there is an implicit spatial disparity that is often ignored. Surface runoff, on the other hand, ...

  6. A Simulation Study of Rater Agreement Measures with 2x2 Contingency Tables

    ERIC Educational Resources Information Center

    Ato, Manuel; Lopez, Juan Jose; Benavente, Ana

    2011-01-01

    A comparison between six rater agreement measures obtained using three different approaches was achieved by means of a simulation study. Rater coefficients suggested by Bennet's [sigma] (1954), Scott's [pi] (1955), Cohen's [kappa] (1960) and Gwet's [gamma] (2008) were selected to represent the classical, descriptive approach, [alpha] agreement…

  7. Life Span as the Measure of Performance and Learning in a Business Gaming Simulation

    ERIC Educational Resources Information Center

    Thavikulwat, Precha

    2012-01-01

    This study applies the learning curve method of measuring learning to participants of a computer-assisted business gaming simulation that includes a multiple-life-cycle feature. The study involved 249 participants. It verified the workability of the feature and estimated the participants' rate of learning at 17.4% for every doubling of experience.…

  8. Epithelial cancers and photon migration: Monte Carlo simulations and diffuse reflectance measurements

    NASA Astrophysics Data System (ADS)

    Tubiana, Jerome; Kass, Alex J.; Newman, Maya Y.; Levitz, David

    2015-07-01

    Detecting pre-cancer in epithelial tissues such as the cervix is a challenging task in low-resources settings. In an effort to achieve low cost cervical cancer screening and diagnostic method for use in low resource settings, mobile colposcopes that use a smartphone as their engine have been developed. Designing image analysis software suited for this task requires proper modeling of light propagation from the abnormalities inside tissues to the camera of the smartphones. Different simulation methods have been developed in the past, by solving light diffusion equations, or running Monte Carlo simulations. Several algorithms exist for the latter, including MCML and the recently developed MCX. For imaging purpose, the observable parameter of interest is the reflectance profile of a tissue under some specific pattern of illumination and optical setup. Extensions of the MCX algorithm to simulate this observable under these conditions were developed. These extensions were validated against MCML and diffusion theory for the simple case of contact measurements, and reflectance profiles under colposcopy imaging geometry were also simulated. To validate this model, the diffuse reflectance profiles of tissue phantoms were measured with a spectrometer under several illumination and optical settings for various homogeneous tissues phantoms. The measured reflectance profiles showed a non-trivial deviation across the spectrum. Measurements of an added absorber experiment on a series of phantoms showed that absorption of dye scales linearly when fit to both MCX and diffusion models. More work is needed to integrate a pupil into the experiment.

  9. Monte Carlo simulation of near infrared autofluorescence measurements of in vivo skin.

    PubMed

    Wang, Shuang; Zhao, Jianhua; Lui, Harvey; He, Qingli; Zeng, Haishan

    2011-12-02

    The autofluorescence properties of normal human skin in the near-infrared (NIR) spectral range were studied using Monte Carlo simulation. The light-tissue interactions including scattering, absorption and anisotropy propagation of the regenerated autofluorescence photons in the skin tissue were taken into account in the theoretical modeling. Skin was represented as a turbid seven-layered medium. To facilitate the simulation, ex vivo NIR autofluorescence spectra and images from different skin layers were measured from frozen skin vertical sections to define the intrinsic fluorescence properties. Monte Carlo simulation was then used to study how the intrinsic fluorescence spectra were distorted by the tissue reabsorption and scattering during in vivo measurements. We found that the reconstructed model skin spectra were in good agreement with the measured in vivo skin spectra from the same anatomical site as the ex vivo tissue sections, demonstrating the usefulness of this modeling. We also found that difference exists over the melanin fluorescent wavelength range (880-910 nm) between the simulated spectrum and the measured in vivo skin spectrum from a different anatomical site. This difference suggests that melanin contents may affect in vivo skin autofluorescence properties, which deserves further investigation.

  10. Evaluation of 16 measures of mental workload using a simulated flight task emphasizing mediational activity

    NASA Technical Reports Server (NTRS)

    Wierwille, W. W.; Rahimi, M.; Casali, J. G.

    1985-01-01

    As aircraft and other systems become more automated, a shift is occurring in human operator participation in these systems. This shift is away from manual control and toward activities that tap the higher mental functioning of human operators. Therefore, an experiment was performed in a moving-base flight simulator to assess mediational (cognitive) workload measurement. Specifically, 16 workload estimation techniques were evaluated as to their sensitivity and intrusion in a flight task emphasizing mediational behavior. Task loading, using navigation problems presented on a display, was treated as an independent variable, and workload-measure values were treated as dependent variables. Results indicate that two mediational task measures, two rating scale measures, time estimation, and two eye behavior measures were reliably sensitive to mediational loading. The time estimation measure did, however, intrude on mediational task performance. Several of the remaining measures were completely insensitive to mediational load.

  11. Backscatter and depolarization measurements of aerosolized biological simulants using a chamber lidar system

    NASA Astrophysics Data System (ADS)

    Brown, David M.; Thrush, Evan P.; Thomas, Michael E.; Santarpia, Josh; Quizon, Jason; Carter, Christopher C.

    2010-04-01

    To ensure agent optical cross sections are well understood from the UV to the LWIR, volume integrated measurements of aerosolized agent material at a few key wavelengths is required to validate existing simulations. Ultimately these simulations will be used to assess the detection performance of various classes of lidar technology spanning the entire range of the optical spectrum. The present work demonstrates an optical measurement architecture based on lidar allowing the measurement of backscatter and depolarization ratio from biological aerosols released in a refereed, 1-m cubic chamber. During 2009, various upgrades have been made to the chamber LIDAR system, which operates at 1.064 μm with sub nanosecond pulses at a 120 Hz repetition rate. The first build of the system demonstrated a sensitivity of aerosolized Bacillus atrophaeus (BG) on the order of 5×105 ppl with 1 GHz InGaAs detectors. To increase the sensitivity and reduce noise, the InGaAs detectors were replaced with larger-area silicon avalanche photodiodes for the second build of the system. In addition, computer controlled step variable neutral density filters are now incorporated to facilitate calibrating the system for absolute back-scatter measurements. Calibrated hard target measurements will be combined with data from the ground truth instruments for cross-section determination of the material aerosolized in the chamber. Measured results are compared to theoretical simulations of cross-sections.

  12. Design Office within the Classroom.

    ERIC Educational Resources Information Center

    Campbell, Kumari

    1980-01-01

    To help architectural students adapt to the realities of the work environment, Gerard Campbell of Holland College has set up his classroom as a design office. Working as a team, the students prepare a complete set of working drawings and construction documents, simulating an actual design process. (JOW)

  13. Numerical simulation and analysis for low-frequency rock physics measurements

    NASA Astrophysics Data System (ADS)

    Dong, Chunhui; Tang, Genyang; Wang, Shangxu; He, Yanxiao

    2017-10-01

    In recent years, several experimental methods have been introduced to measure the elastic parameters of rocks in the relatively low-frequency range, such as differential acoustic resonance spectroscopy (DARS) and stress-strain measurement. It is necessary to verify the validity and feasibility of the applied measurement method and to quantify the sources and levels of measurement error. Relying solely on the laboratory measurements, however, we cannot evaluate the complete wavefield variation in the apparatus. Numerical simulations of elastic wave propagation, on the other hand, are used to model the wavefield distribution and physical processes in the measurement systems, and to verify the measurement theory and analyze the measurement results. In this paper we provide a numerical simulation method to investigate the acoustic waveform response of the DARS system and the quasi-static responses of the stress-strain system, both of which use axisymmetric apparatus. We applied this method to parameterize the properties of the rock samples, the sample locations and the sensor (hydrophone and strain gauges) locations and simulate the measurement results, i.e. resonance frequencies and axial and radial strains on the sample surface, from the modeled wavefield following the physical experiments. Rock physical parameters were estimated by inversion or direct processing of these data, and showed a perfect match with the true values, thus verifying the validity of the experimental measurements. Error analysis was also conducted for the DARS system with 18 numerical samples, and the sources and levels of error are discussed. In particular, we propose an inversion method for estimating both density and compressibility of these samples. The modeled results also showed fairly good agreement with the real experiment results, justifying the effectiveness and feasibility of our modeling method.

  14. Measurement with microscopic MRI and simulation of flow in different aneurysm models

    SciTech Connect

    Edelhoff, Daniel Frank, Frauke; Heil, Marvin; Suter, Dieter; Walczak, Lars; Weichert, Frank; Schmitz, Inge

    2015-10-15

    Purpose: The impact and the development of aneurysms depend to a significant degree on the exchange of liquid between the regular vessel and the pathological extension. A better understanding of this process will lead to improved prediction capabilities. The aim of the current study was to investigate fluid-exchange in aneurysm models of different complexities by combining microscopic magnetic resonance measurements with numerical simulations. In order to evaluate the accuracy and applicability of these methods, the fluid-exchange process between the unaltered vessel lumen and the aneurysm phantoms was analyzed quantitatively using high spatial resolution. Methods: Magnetic resonance flow imaging was used to visualize fluid-exchange in two different models produced with a 3D printer. One model of an aneurysm was based on histological findings. The flow distribution in the different models was measured on a microscopic scale using time of flight magnetic resonance imaging. The whole experiment was simulated using fast graphics processing unit-based numerical simulations. The obtained simulation results were compared qualitatively and quantitatively with the magnetic resonance imaging measurements, taking into account flow and spin–lattice relaxation. Results: The results of both presented methods compared well for the used aneurysm models and the chosen flow distributions. The results from the fluid-exchange analysis showed comparable characteristics concerning measurement and simulation. Similar symmetry behavior was observed. Based on these results, the amount of fluid-exchange was calculated. Depending on the geometry of the models, 7% to 45% of the liquid was exchanged per second. Conclusions: The result of the numerical simulations coincides well with the experimentally determined velocity field. The rate of fluid-exchange between vessel and aneurysm was well-predicted. Hence, the results obtained by simulation could be validated by the experiment. The

  15. Post-Shot Simulations of NIC Experiments with Comparison to X-ray Measurements

    NASA Astrophysics Data System (ADS)

    Eder, David; Jones, Oggie; Suter, Larry; Moore, Alastair; Schneider, Marilyn

    2012-10-01

    National Ignition Campaign experiments at NIF are ongoing and post-shot simulations play an important role in understanding the physical processes occurring in the quest for demonstrating fusion burn. In particular, it is important to understand the x-ray environment inside the hohlraum targets, which is studied using various x-ray diagnostics. The Dante instrument measures the time dependent x-ray emission escaping out of the hohlraum laser entrance holes (LEHs) and the SXI instrument provides a time-integrated image of both soft and hard x-rays. We compare calculated total x-ray emission with Dante data as well as the relative high energy Mband emission that contributes to capsule preheat. We correct our calculated x-ray emission to account for differences between simulation and data on LEH closure using SXI data. We provide results for both ``standard candle'' simulation with no added multipliers and for simulations with time-dependent multipliers that are used to obtain agreement with shock timing and implosion velocity data. The physics justification for the use of multipliers is to account for potential missing energy or incorrect ablation modeling. The relative importance of these two effects can be studied through comparison of post-shot simulations with x-ray measurements.

  16. Temperature and wavelength dependent measurement and simulation of Fresnel lenses for concentrating photovoltaics

    NASA Astrophysics Data System (ADS)

    Hornung, Thorsten; Bachmaier, Andreas; Nitz, Peter; Gombert, Andreas

    2010-05-01

    Fresnel lenses are often used as primary optical components in concentrating photovoltaics (CPV). When applied in the field, varying conditions during operation lead to variations in lens temperature which has a strong impact on the optical efficiency of the lenses. A setup for indoor characterization with the ability to heat lens plates allows for the assessment of the quality of Fresnel lenses by means of their irradiance profiles in the focal plane. To analyze the measured temperature dependency we simulate thermal deformations of the lens geometry with finite element method (FEM) tools and use the resulting lens geometry as an input to ray tracing simulations. A close match between computer simulations and measurements of the irradiance profile in the focal plane is achieved, validating our simulation approach. This allows us to judge and optimize the temperature dependence of new lens designs before building and testing prototypes. The simulation enables us to analyze and understand all superimposed effects in detail. The developed tools in combination with detailed solar resource data and knowledge of the CPV system will be the basis for future assessment of overall performance and further optimization of optics for CPV applications.

  17. Simulations and measurements of annealed pyrolytic graphite-metal composite baseplates

    NASA Astrophysics Data System (ADS)

    Streb, F.; Ruhl, G.; Schubert, A.; Zeidler, H.; Penzel, M.; Flemmig, S.; Todaro, I.; Squatrito, R.; Lampke, T.

    2016-03-01

    We investigated the usability of anisotropic materials as inserts in aluminum-matrix-composite baseplates for typical high performance power semiconductor modules using finite-element simulations and transient plane source measurements. For simulations, several physical modules can be used, which are suitable for different thermal boundary conditions. By comparing different modules and options of heat transfer we found non-isothermal simulations to be closest to reality for temperature distribution at the surface of the heat sink. We optimized the geometry of the graphite inserts for best heat dissipation and based on these results evaluated the thermal resistance of a typical power module using calculation time optimized steady-state simulations. Here we investigated the influence of thermal contact conductance (TCC) between metal matrix and inserts on the heat dissipation. We found improved heat dissipation compared to the plain metal baseplate for a TCC of 200 kW/m2/K and above.To verify the simulations we evaluated cast composite baseplates with two different insert geometries and measured their averaged lateral thermal conductivity using a transient plane source (HotDisk) technique at room temperature. For the composite baseplate we achieved local improvements in heat dissipation compared to the plain metal baseplate.

  18. Contributions of numerical simulation data bases to the physics, modeling and measurement of turbulence

    NASA Technical Reports Server (NTRS)

    Moin, Parviz; Spalart, Philippe R.

    1987-01-01

    The use of simulation data bases for the examination of turbulent flows is an effective research tool. Studies of the structure of turbulence have been hampered by the limited number of probes and the impossibility of measuring all desired quantities. Also, flow visualization is confined to the observation of passive markers with limited field of view and contamination caused by time-history effects. Computer flow fields are a new resource for turbulence research, providing all the instantaneous flow variables in three-dimensional space. Simulation data bases also provide much-needed information for phenomenological turbulence modeling. Three dimensional velocity and pressure fields from direct simulations can be used to compute all the terms in the transport equations for the Reynolds stresses and the dissipation rate. However, only a few, geometrically simple flows have been computed by direct numerical simulation, and the inventory of simulation does not fully address the current modeling needs in complex turbulent flows. The availability of three-dimensional flow fields also poses challenges in developing new techniques for their analysis, techniques based on experimental methods, some of which are used here for the analysis of direct-simulation data bases in studies of the mechanics of turbulent flows.

  19. A virtual reality endoscopic simulator augments general surgery resident cancer education as measured by performance improvement.

    PubMed

    White, Ian; Buchberg, Brian; Tsikitis, V Liana; Herzig, Daniel O; Vetto, John T; Lu, Kim C

    2014-06-01

    Colorectal cancer is the second most common cause of death in the USA. The need for screening colonoscopies, and thus adequately trained endoscopists, particularly in rural areas, is on the rise. Recent increases in required endoscopic cases for surgical resident graduation by the Surgery Residency Review Committee (RRC) further emphasize the need for more effective endoscopic training during residency to determine if a virtual reality colonoscopy simulator enhances surgical resident endoscopic education by detecting improvement in colonoscopy skills before and after 6 weeks of formal clinical endoscopic training. We conducted a retrospective review of prospectively collected surgery resident data on an endoscopy simulator. Residents performed four different clinical scenarios on the endoscopic simulator before and after a 6-week endoscopic training course. Data were collected over a 5-year period from 94 different residents performing a total of 795 colonoscopic simulation scenarios. Main outcome measures included time to cecal intubation, "red out" time, and severity of simulated patient discomfort (mild, moderate, severe, extreme) during colonoscopy scenarios. Average time to intubation of the cecum was 6.8 min for those residents who had not undergone endoscopic training versus 4.4 min for those who had undergone endoscopic training (p < 0.001). Residents who could be compared against themselves (pre vs. post-training), cecal intubation times decreased from 7.1 to 4.3 min (p < 0.001). Post-endoscopy rotation residents caused less severe discomfort during simulated colonoscopy than pre-endoscopy rotation residents (4 vs. 10%; p = 0.004). Virtual reality endoscopic simulation is an effective tool for both augmenting surgical resident endoscopy cancer education and measuring improvement in resident performance after formal clinical endoscopic training.

  20. Technical skills measurement based on a cyber-physical system for endovascular surgery simulation.

    PubMed

    Tercero, Carlos; Kodama, Hirokatsu; Shi, Chaoyang; Ooe, Katsutoshi; Ikeda, Seiichi; Fukuda, Toshio; Arai, Fumihito; Negoro, Makoto; Kwon, Guiryong; Najdovski, Zoran

    2013-09-01

    Quantification of medical skills is a challenge, particularly simulator-based training. In the case of endovascular intervention, it is desirable that a simulator accurately recreates the morphology and mechanical characteristics of the vasculature while enabling scoring. For this purpose, we propose a cyber-physical system composed of optical sensors for a catheter's body motion encoding, a magnetic tracker for motion capture of an operator's hands, and opto-mechatronic sensors for measuring the interaction of the catheter tip with the vasculature model wall. Two pilot studies were conducted for measuring technical skills, one for distinguishing novices from experts and the other for measuring unnecessary motion. The proficiency levels were measurable between expert and novice and also between individual novice users. The results enabled scoring of the user's proficiency level, using sensitivity, reaction time, time to complete a task and respect for tissue integrity as evaluation criteria. Additionally, unnecessary motion was also measurable. The development of cyber-physical simulators for other domains of medicine depend on the study of photoelastic materials for human tissue modelling, and enables quantitative evaluation of skills using surgical instruments and a realistic representation of human tissue. Copyright © 2012 John Wiley & Sons, Ltd.

  1. Measurement of plasma current dependent changes in impurity transport and comparison with nonlinear gyrokinetic simulation

    SciTech Connect

    Howard, N. T.; Greenwald, M.; White, A. E.; Reinke, M. L.; Ernst, D.; Podpaly, Y.; Mikkelsen, D. R.; Candy, J.

    2012-05-15

    Measured impurity transport coefficients are found to demonstrate a strong dependence on plasma current in the core of Alcator C-Mod. These measurements are compared directly with linear and nonlinear gyrokinetic simulation in an attempt to both qualitatively and quantitatively reproduce the measured impurity transport. Discharges constituting a scan of plasma current from 0.6 to 1.2 MA were performed during the 2010 run campaign. The impurity transport from these discharges was determined using a novel set of spectroscopic diagnostics available on Alcator C-Mod. This diagnostic suite allowed for the effective constraint of impurity transport coefficient profiles inside of r/a = 0.6. A decrease in the measured impurity diffusivity and inward convection is found with increased plasma current. Global, nonlinear gyrokinetic simulations were performed using the GYRO code [J. Candy and R. E. Waltz, J Comput. Phys. 186, 545 (2003)] for all discharges in the experimental scan and are found to reproduce the experimental trends, while demonstrating good quantitative agreement with measurement. A more comprehensive quantitative comparison was performed on the 0.8 MA discharge of the current scan which demonstrates that simultaneous agreement between experiment and simulation in both the impurity particle transport and ion heat transport channels is attainable within experimental uncertainties.

  2. A new satellite simulator tool for global model-measurements intercomparisons

    NASA Astrophysics Data System (ADS)

    Khlystova, Iryna; Schreier, Mathias; Bovensmann, Heinrich; Sausen, Robert; Burrows, John P.

    A new satellite simulation tool has been developed at the University of Bremen in cooperation with the DLR IPA in Muenchen. The original objective of this tool was to simplify and unify all typical comparison steps performed repeatedly by different research groups for comparisons of the global measurements of an atmospheric trace species with corresponding model fields. To answer the main requirements, the SatSim tool was designed as an extendable (based on concepts of Object-Oriented Programming) and flexible relative to the format of the input data tool. The latter allows the integration of the SatSim into a chemistry-transport model facility as a post-processing routine as well as its independent usage. Additionally, as it has become clear through the development process, SatSim can be also used as a validation tool for different satellite measurements. Being independent of the retrieval procedure, which is required in order to obtain a trace-species information from satellites radiometric measurements, this tool allows comparisons of the modelled fields of several atmospheric trace species as if they were measured by satellite instruments. Such approach provides an insight into the differences of the instrumental measurement precision caused only by the difference in the ground tracks geometry and related differences in the cloud coverage of the observed scenes. An example of the simulated SCIAMACHY and MOPITT CO observations based on the ECHAM5/Messy1 simulated global CO fields will be presented.

  3. Beam emittance measurements and simulations of injector line for radio frequency quadrupole

    NASA Astrophysics Data System (ADS)

    Mathew, Jose V.; Rao, S. V. L. S.; Pande, Rajni; Singh, P.

    2015-07-01

    A 400 keV deuteron (D+) radio frequency quadrupole (RFQ) accelerator has been designed, built, and commissioned at the Bhabha Atomic Research Centre, India. A beam line has been developed for injecting deuterons into the 400 keV RFQ. This comprises of a RF plasma ion source and a low energy beam transport (LEBT) system, consisting of two solenoid magnets and two steerer magnets. The ion source is characterized in terms of transverse beam emittance. A slit-wire scanner based emittance measurement setup has been developed for the transverse emittance measurements of H+ and D+ beams. The measured emittance values are found to be well within the acceptance value for the RFQ. These measured emittance parameters are used to optimize the solenoid fields in LEBT to match the beam from the ion source to RFQ. TRACEWIN simulation code is used for the beam transport simulations. The simulations show 99% transmission of D+ beam through the RFQ, while 95% transmission has been measured experimentally.

  4. Beam emittance measurements and simulations of injector line for radio frequency quadrupole.

    PubMed

    Mathew, Jose V; Rao, S V L S; Pande, Rajni; Singh, P

    2015-07-01

    A 400 keV deuteron (D(+)) radio frequency quadrupole (RFQ) accelerator has been designed, built, and commissioned at the Bhabha Atomic Research Centre, India. A beam line has been developed for injecting deuterons into the 400 keV RFQ. This comprises of a RF plasma ion source and a low energy beam transport (LEBT) system, consisting of two solenoid magnets and two steerer magnets. The ion source is characterized in terms of transverse beam emittance. A slit-wire scanner based emittance measurement setup has been developed for the transverse emittance measurements of H(+) and D(+) beams. The measured emittance values are found to be well within the acceptance value for the RFQ. These measured emittance parameters are used to optimize the solenoid fields in LEBT to match the beam from the ion source to RFQ. TRACEWIN simulation code is used for the beam transport simulations. The simulations show 99% transmission of D(+) beam through the RFQ, while 95% transmission has been measured experimentally.

  5. Comparison of Different Measurement Techniques and a CFD Simulation in Complex Terrain

    NASA Astrophysics Data System (ADS)

    Schulz, Christoph; Hofsäß, Martin; Anger, Jan; Rautenberg, Alexander; Lutz, Thorsten; Cheng, Po Wen; Bange, Jens

    2016-09-01

    This paper deals with a comparison of data collected by measurements and a simulation for a complex terrain test site in southern Germany. Lidar, met mast, unmanned aerial vehicle (UAV) measurements of wind speed and direction and Computational Fluid Dynamics (CFD) data are compared to each other. The site is characterised regarding its flow features and the suitability for a wind turbine test field. A Delayed-Detached-Eddy- Simulation (DES) was employed using measurement data to generate generic turbulent inflow. A good agreement of the wind profiles between the different approaches was reached. The terrain slope leads to a speed-up, a change of turbulence intensity as well as to flow angle variations.

  6. Experimental and numerical simulation of a TPC like set up for the measurement of ion backflow

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Deb Sankar; Bhattacharya, Purba; Rout, Prasant Kumar; Mukhopadhyay, Supratik; Bhattacharya, Sudeb; Majumdar, Nayana; Sarkar, Sandip; Colas, Paul; Atti'e, David; Ganjour, Serguei; Bhattacharya, Aparajita

    2017-07-01

    Ion backflow is one of the effects limiting the operation of a gaseous detector at high flux, by giving rise to space charge which perturbs the electric field. The natural ability of bulk Micromegas to suppress ion feedback is very effective and can help the TPC drift volume to remain relatively free of space charge build-up. An efficient and precise measurement of the backflow fraction is necessary to cope up with the track distortion due to the space charge effect. In a subtle but significant modification of the usual approach, we have made use of two drift meshes in order to measure the ion backflow fraction for bulk Micromegas detector. This helps to truly represent the backflow fraction for a TPC. Moreover, attempt is taken to optimize the field configuration between the drift meshes. In conjunction with the experimental measurement, Garfield simulation framework has been used to simulate the related physics processes numerically.

  7. Simulation of interface states effect on the scanning capacitance microscopy measurement of p-n junctions

    NASA Astrophysics Data System (ADS)

    Yang, J.; Kong, F. C. J.

    2002-12-01

    A two-dimensional numerical simulation model of interface states in scanning capacitance microscopy (SCM) measurements of p-n junctions is presented. In the model, amphoteric interface states with two transition energies in the Si band gap are represented as fixed charges to account for their behavior in SCM measurements. The interface states are shown to cause a stretch-out and a parallel shift of the capacitance-voltage characteristics in the depletion and neutral regions of p-n junctions, respectively. This explains the discrepancy between the SCM measurement and simulation near p-n junctions, and thus modeling interface states is crucial for SCM dopant profiling of p-n junctions.

  8. Flow dynamics at a river confluence on Mississippi River: field measurement and large eddy simulation

    NASA Astrophysics Data System (ADS)

    Le, Trung; Khosronejad, Ali; Bartelt, Nicole; Woldeamlak, Solomon; Peterson, Bonnie; Dewall, Petronella; Sotiropoulos, Fotis; Saint Anthony Falls Laboratory, University of Minnesota Team; Minnesota Department of Transportation Team

    2015-11-01

    We study the dynamics of a river confluence on Mississippi River branch in the city of Minneapolis, Minnesota, United States. Field measurements by Acoustic Doppler Current Profiler using on-board GPS tracking were carried out for five campaigns in the summer of 2014 and 2015 to collect both river bed elevation data and flow fields. Large Eddy Simulation is carried out to simulate the flow field with the total of 100 million grid points for the domain length of 3.2 km. The simulation results agree well with field measurements at measured cross-sections. The results show the existence of wake mode on the mixing interface of two branches near the upstream junction corner. The mutual interaction between the shear layers emanating from the river banks leading to the formation of large scale energetic structures that leads to ``switching'' side of the flow coherent structures. Our result here is a feasibility study for the use of eddy-resolving simulations in predicting complex flow dynamics in medium-size natural rivers. This work is funded by Minnesota Dept. Transportation and Minnesota Institute of Supercomputing.

  9. Development of measurement simulation of the laser dew-point hygrometer using an optical fiber cable

    NASA Astrophysics Data System (ADS)

    Matsumoto, Shigeaki

    2005-02-01

    In order to improve the initial and the response times of the Laser Dew-Point Hygrometer (LDH), the measurement simulation was developed on the basis of the loop computation of the surface temperature of a gold plate for dew depostition, the quantity of deposited dew and the intensity of scattered light from the surface of the plate at time interval of 5 sec during measurement. A more detailed relationship between the surface temperature of the plate and the cooling current, and the time constant of the integrator in the control circuit of the LDH were introduced in the simulation program as a function of atmospheric temperature. The simulation was more close to the actual measurement by the LDH. The simulation results indicated the possibility of improving both the times of teh LDH by the increase of the sensitivity of dew and that of the mass transfer coefficient of dew deposited on the plate surface. It was concluded that the initial and the response times could be improved to below 100sec and 120 sec, respectively in the dew-point range at room temperature, that are almost half of the those times of the original LDH.

  10. Metabolic rate control during extravehicular activity simulations and measurement techniques during actual EVAS

    NASA Technical Reports Server (NTRS)

    Horrigan, D. J.

    1975-01-01

    A description of the methods used to control and measure metabolic rate during ground simulations is given. Work levels attained at the Space Environment Simulation Laboratory are presented. The techniques and data acquired during ground simulations are described and compared with inflight procedures. Data from both the Skylab and Apollo Program were utilized and emphasis is given to the methodology, both in simulation and during flight. The basic techniques of work rate assessment are described. They include oxygen consumption, which was useful for averages over long time periods, heart rate correlations based on laboratory calibrations, and liquid cooling garment temperature changes. The relative accuracy of these methods as well as the methods of real-time monitoring at the Mission Control Center are discussed. The advantages and disadvantages of each of the metabolic measurement techniques are discussed. Particular emphasis is given to the problem of utilizing oxygen decrement for short time periods and heart rate at low work levels. A summary is given of the effectiveness of work rate control and measurements; and current plans for future EVA monitoring are discussed.

  11. Metabolic rate control during extravehicular activity simulations and measurement techniques during actual EVAS

    NASA Technical Reports Server (NTRS)

    Horrigan, D. J.

    1975-01-01

    A description of the methods used to control and measure metabolic rate during ground simulations is given. Work levels attained at the Space Environment Simulation Laboratory are presented. The techniques and data acquired during ground simulations are described and compared with inflight procedures. Data from both the Skylab and Apollo Program were utilized and emphasis is given to the methodology, both in simulation and during flight. The basic techniques of work rate assessment are described. They include oxygen consumption, which was useful for averages over long time periods, heart rate correlations based on laboratory calibrations, and liquid cooling garment temperature changes. The relative accuracy of these methods as well as the methods of real-time monitoring at the Mission Control Center are discussed. The advantages and disadvantages of each of the metabolic measurement techniques are discussed. Particular emphasis is given to the problem of utilizing oxygen decrement for short time periods and heart rate at low work levels. A summary is given of the effectiveness of work rate control and measurements; and current plans for future EVA monitoring are discussed.

  12. Qualification of concentrating mirror systems with the Hermes measurement system and the Helios simulation program

    NASA Astrophysics Data System (ADS)

    Kleih, Juergen

    1991-02-01

    An overview of methods (direct and indirect) for measuring highly concentrated solar radiation, which were used for qualifying solar power plants (from the parabolic mirror up to the tower plant) is provided. In particular, it goes into the Hermes measuring system which was used to measure two membrane mirrors (of diameter 17 and 7.5 m respectively). Measurements were made of maximum radiant flux densities of more than 2 MW/sq m for the 17 m mirror and of more than 9 MW/sq m for the 7.5 m mirror. The HELIOS simulation program was used to check the measurement results. The agreement between measurement and calculation was satisfactory over all.

  13. First fast-ion D-alpha (FIDA) measurements and simulations on C-2U

    SciTech Connect

    Bolte, N. G. Gupta, D.; Onofri, M.; Dettrick, S.; Granstedt, E. M.; Petrov, P.; Stagner, L.

    2016-11-15

    The first measurements of fast-ion D-alpha (FIDA) radiation have been acquired on C-2U, Tri Alpha Energy’s advanced, beam-driven field-reversed configuration (FRC). These measurements are also forward modeled by FIDASIM. This is the first measurement and simulation of FIDA carried out on an FRC topology. FIDA measurements are made of Doppler-shifted Balmer-alpha light from neutralized fast ions using a bandpass filter and photomultiplier tube. One adjustable line-of-sight measured signals at eight locations and eight times during the FRC lifetime over 26 discharges. Filtered signals include only the highest energy ions (>6 keV) and share some salient features with the FIDASIM result. Highly Doppler-shifted beam radiation is also measured with a high-speed camera and is spatially well-correlated with FIDASIM.

  14. Comparison of beam transport simulations to measurements at the Los Alamos Proton Storage Ring

    SciTech Connect

    Wilkinson, C.; Neri, F.; Fitzgerald, D.H.; Blind, B.; Macek, R.; Plum, M.; Sander, O.; Thiessen, H.A.

    1997-10-01

    The ability to model and simulate beam behavior in the Proton Storage Ring (PSR) of the Los Alamos Neutron Science Center (LANSCE) is an important diagnostic and predictive tool. This paper gives the results of an effort to model the ring apertures and lattice and use beam simulation programs to track the beam. The results are then compared to measured activation levels from beam loss in the ring. The success of the method determines its usefulness in evaluating the effects of planned upgrades to the Proton Storage Ring.

  15. Turbulence in the TORE SUPRA Tokamak: Measurements and Validation of Nonlinear Simulations

    SciTech Connect

    Casati, A.; Bourdelle, C.; Clairet, F.; Garbet, X.; Grandgirard, V.; Hoang, G. T.; Imbeaux, F.; Sabot, R.; Sarazin, Y.; Gerbaud, T.; Hennequin, P.; Guercan, Oe. D.; Honore, C.; Vermare, L.; Candy, J.; Waltz, R. E.; Heuraux, S.

    2009-04-24

    Turbulence measurements in TORE SUPRA tokamak plasmas have been quantitatively compared to predictions by nonlinear gyrokinetic simulations. For the first time, numerical results simultaneously match within experimental uncertainty (a) the magnitude of effective heat diffusivity, (b) rms values of density fluctuations, and (c) wave-number spectra in both the directions perpendicular to the magnetic field. Moreover, the nonlinear simulations help to revise as an instrumental effect the apparent experimental evidence of strong turbulence anisotropy at spatial scales of the order of ion-sound Larmor radius.

  16. Interpretation of experiments measuring the back face of thin aluminum strips by comparison with numerical simulations

    NASA Astrophysics Data System (ADS)

    Benattar, Rene; Malka, Victor

    1990-04-01

    Experiments using X-UV imagery which show the importance of radiative transfer during ablation of Z weak material, such as aluminum, by a high power ultraviolet laser are described. Measurements are compared with two mumerical simulation programs (MULTI and FILM). Shock propagation shows a correct dependence in relation to the thickness of the film. The back face temperatures are perfectly reproduced by the MULTI simulations, including the radiative transfer. The agreement between experiment and MULTI shows the importance of radiation transfer in this type of interaction. The temperature of the back face is determined more by radiative heating than by shock wave heating, in particular for the thinnest films (5 micrometers).

  17. Simulating of the measurement-device independent quantum key distribution with phase randomized general sources

    PubMed Central

    Wang, Qin; Wang, Xiang-Bin

    2014-01-01

    We present a model on the simulation of the measurement-device independent quantum key distribution (MDI-QKD) with phase randomized general sources. It can be used to predict experimental observations of a MDI-QKD with linear channel loss, simulating corresponding values for the gains, the error rates in different basis, and also the final key rates. Our model can be applicable to the MDI-QKDs with arbitrary probabilistic mixture of different photon states or using any coding schemes. Therefore, it is useful in characterizing and evaluating the performance of the MDI-QKD protocol, making it a valuable tool in studying the quantum key distributions. PMID:24728000

  18. Comparison of CFD simulations and measurements of flow affected by coanda effect

    NASA Astrophysics Data System (ADS)

    Fišer, Jan; Jedelský, Jan; Vach, Tomáš; Forman, Matěj; Jícha, Miroslav

    2012-04-01

    The article deals with experimental research and numerical simulations of specific phenomena in fluid flows called Coanda effect (CE), which has numerous important engineering applications. Although many researchers have concerned with wall jets, the physics of this flow still remains not well understood. This study is focused on analysis of behaviour of jet flow close to the wall and influence of its inclination. The flow has been visualized using smoke and velocity was measured by means of Hot Wire Anemometry (HWA). CFD simulations have been performed on the same geometry and compared with experiments in order to find a tool for correct prediction of the CE.

  19. Arrayed waveguide grating interrogator for fiber Bragg grating sensors: measurement and simulation.

    PubMed

    Koch, Jan; Angelmahr, Martin; Schade, Wolfgang

    2012-11-01

    A fiber Bragg grating (FBG) interrogation system based on an intensity demodulation and demultiplexing of an arrayed waveguide grating (AWG) module is examined in detail. The influence of the spectral line shape of the FBG on the signal obtained from the AWG device is discussed by accomplishing the measurement and simulation of the system. The simulation of the system helps to create quickly and precisely calibration functions for nonsymmetric, tilted, or nonapodized FBGs. Experiments show that even small sidebands of nonapodized FBGs have strong influences on the signal resulted by an AWG device with a Gaussian profile.

  20. Nonadiabatic molecular dynamics simulation: An approach based on quantum measurement picture

    SciTech Connect

    Feng, Wei; Xu, Luting; Li, Xin-Qi; Fang, Weihai; Yan, YiJing

    2014-07-15

    Mixed-quantum-classical molecular dynamics simulation implies an effective quantum measurement on the electronic states by the classical motion of atoms. Based on this insight, we propose a quantum trajectory mean-field approach for nonadiabatic molecular dynamics simulations. The new protocol provides a natural interface between the separate quantum and classical treatments, without invoking artificial surface hopping algorithm. Moreover, it also bridges two widely adopted nonadiabatic dynamics methods, the Ehrenfest mean-field theory and the trajectory surface-hopping method. Excellent agreement with the exact results is illustrated with representative model systems, including the challenging ones for traditional methods.

  1. Comparisons of Measurements and Gyrofluid Simulations of Turbulence in DIII--D

    NASA Astrophysics Data System (ADS)

    Bravenec, R. V.; Ross, D. W.; Austin, M. E.; Patterson, D. M.; Rowan, W. L.; McKee, G. R.; Fonck, R. J.; Burrell, K. H.; Deboo, J. C.; Greenfield, C. M.; Dorland, W.; Kotschenreuther, M.; Beer, M. A.; Hammett, G. W.

    1998-11-01

    Initial comparisons(R.V. Bravenec, D.W. Ross, G.R. McKee, et al)., in Proc. 25th EPS Conf. on Contr. Fusion and Plasma Phys., Prague (1998). have been made between time-averaged measurements of density fluctuations from beam-emission spectroscopy (BES) on DIII--D and nonlinear gyrofluid simulations using the PPPL/ IFS gyrofluid code.(M.A. Beer, Ph.D. thesis, Princeton University (1995).) In this work we extend the previous work to a time-dependent study of discharges with modulated electron-cyclotron heating, where we model the heating modulations in the simulations as perturbations of the local plasma profiles.

  2. Ionic diffusion in quartz studied by transport measurements, SIMS and atomistic simulations

    NASA Astrophysics Data System (ADS)

    Sartbaeva, Asel; Wells, Stephen A.; Redfern, Simon A. T.; Hinton, Richard W.; Reed, Stephen J. B.

    2005-02-01

    Ionic diffusion in the quartz-β-eucryptite system is studied by DC transport measurements, SIMS and atomistic simulations. Transport data show a large transient increase in ionic current at the α-β phase transition of quartz (the Hedvall effect). The SIMS data indicate two diffusion processes, one involving rapid Li+ motion and the other involving penetration of Al and Li atoms into quartz at the phase transition. Atomistic simulations explain why the fine microstructure of twin domain walls in quartz near the transition does not hinder Li+ diffusion.

  3. Double-Pulse Two-Micron IPDA Lidar Simulation for Airborne Carbon Dioxide Measurements

    NASA Technical Reports Server (NTRS)

    Refaat, Tamer F.; Singh, Upendra N.; Yu, Jirong; Petros, Mulugeta

    2015-01-01

    An advanced double-pulsed 2-micron integrated path differential absorption lidar has been developed at NASA Langley Research Center for measuring atmospheric carbon dioxide. The instrument utilizes a state-of-the-art 2-micron laser transmitter with tunable on-line wavelength and advanced receiver. Instrument modeling and airborne simulations are presented in this paper. Focusing on random errors, results demonstrate instrument capabilities of performing precise carbon dioxide differential optical depth measurement with less than 3% random error for single-shot operation from up to 11 km altitude. This study is useful for defining CO2 measurement weighting, instrument setting, validation and sensitivity trade-offs.

  4. Fission prompt gamma-ray multiplicity distribution measurements and simulations at DANCE

    SciTech Connect

    Chyzh, A; Wu, C Y; Ullmann, J; Jandel, M; Bredeweg, T; Couture, A; Norman, E

    2010-08-24

    The nearly energy independence of the DANCE efficiency and multiplicity response to {gamma} rays makes it possible to measure the prompt {gamma}-ray multiplicity distribution in fission. We demonstrate this unique capability of DANCE through the comparison of {gamma}-ray energy and multiplicity distribution between the measurement and numerical simulation for three radioactive sources {sup 22}Na, {sup 60}Co, and {sup 88}Y. The prospect for measuring the {gamma}-ray multiplicity distribution for both spontaneous and neutron-induced fission is discussed.

  5. Mean horizontal wind profiles measured in the atmospheric boundary layer about a simulated block building

    NASA Technical Reports Server (NTRS)

    Frost, W.; Connell, J. R.; Hutto, M. L.; Fichtl, G.

    1977-01-01

    Instrumented wind towers are used to measure the three components of wind about a simulated block building. The mean horizontal wind profiles over the building are compared with wind profiles measured in the absence of the building and the wind speed deficit in the wake of the building is correlated. The turbulence intensity is of the order of 20% in the undisturbed flow whereas the free stream turbulence intensity of wind-tunnel studies is generally not more than 5%. The velocity profiles measured in the undisturbed flow zones support the representation of a neutrally stable atmospheric boundary layer with a logarithmic wind profile.

  6. Measurement of transient strain and surface temperature on simulated turbine blades using noncontacting techniques

    NASA Technical Reports Server (NTRS)

    Calfo, F. D.; Pollack, F. G.

    1978-01-01

    Noncontacting techniques were used to measure strain and temperature in thermally cycled simulated turbine blades. An electro-optical extensometer was used to measure the displacement between parallel targets mounted on the leading edge of the blades throughout a complete heating and cooling cycle. An infrared photographic pyrometry method was used to measure blade steady state surface temperature. The blade was cyclically heated and cooled by moving it into and out of a Mach 1 hot-gas stream. Transient leading edge strain and steady state surface temperature distributions are presented for blades of three different configurations.

  7. Dose reduction in CT using bismuth shielding: measurements and Monte Carlo simulations

    PubMed Central

    Chang, Kyung-Hwan; Lee, Wonho; Choo, Dong-Myung; Lee, Choon-Sik; Kim, Youhyun

    2010-01-01

    In this research, using direct measurements and Monte Carlo calculations, the potential dose reduction achieved by bismuth shielding in computed tomography was evaluated. The patient dose was measured using an ionisation chamber in a polymethylmethacrylate (PMMA) phantom that had five measurement points at the centre and periphery. Simulations were performed using the MCNPX code. For both the bare and the bismuth-shielded phantom, the differences of dose values between experiment and simulation were within 9 %. The dose reductions due to the bismuth shielding were 1.2–55 % depending on the measurement points, X-ray tube voltage and the type of shielding. The amount of dose reduction was significant for the positions covered by the bismuth shielding (34 − 46 % for head and 41 − 55 % for body phantom on average) and negligible for other peripheral positions. The artefact on the reconstructed images were minimal when the distance between the shielding and the organs was >1 cm, and hence the shielding should be selectively located to protect critical organs such as the eye lens, thyroid and breast. The simulation results using the PMMA phantom was compared with those using a realistically voxelised phantom (KTMAN-2). For eye and breast, the simulation results using the PMMA and KTMAN-2 phantoms were similar with each other, while for thyroid the simulation results were different due to the discrepancy of locations and the sizes of the phantoms. The dose reductions achieved by bismuth and lead shielding were compared with each other and the results showed that the difference of the dose reductions achieved by the two materials was less than 2–3 %. PMID:19959602

  8. Atomic force microscope adhesion measurements and atomistic molecular dynamics simulations at different humidities

    NASA Astrophysics Data System (ADS)

    Seppä, Jeremias; Reischl, Bernhard; Sairanen, Hannu; Korpelainen, Virpi; Husu, Hannu; Heinonen, Martti; Raiteri, Paolo; Rohl, Andrew L.; Nordlund, Kai; Lassila, Antti

    2017-03-01

    Due to their operation principle atomic force microscopes (AFMs) are sensitive to all factors affecting the detected force between the probe and the sample. Relative humidity is an important and often neglected—both in experiments and simulations—factor in the interaction force between AFM probe and sample in air. This paper describes the humidity control system designed and built for the interferometrically traceable metrology AFM (IT-MAFM) at VTT MIKES. The humidity control is based on circulating the air of the AFM enclosure via dryer and humidifier paths with adjustable flow and mixing ratio of dry and humid air. The design humidity range of the system is 20–60 %rh. Force–distance adhesion studies at humidity levels between 25 %rh and 53 %rh are presented and compared to an atomistic molecular dynamics (MD) simulation. The uncertainty level of the thermal noise method implementation used for force constant calibration of the AFM cantilevers is 10 %, being the dominant component of the interaction force measurement uncertainty. Comparing the simulation and the experiment, the primary uncertainties are related to the nominally 7 nm radius and shape of measurement probe apex, possible wear and contamination, and the atomistic simulation technique details. The interaction forces are of the same order of magnitude in simulation and measurement (5 nN). An elongation of a few nanometres of the water meniscus between probe tip and sample, before its rupture, is seen in simulation upon retraction of the tip in higher humidity. This behaviour is also supported by the presented experimental measurement data but the data is insufficient to conclusively verify the quantitative meniscus elongation.

  9. Numerical simulations to assess the tracer dilution method for measurement of landfill methane emissions.

    PubMed

    Taylor, Diane M; Chow, Fotini K; Delkash, Madjid; Imhoff, Paul T

    2016-10-01

    Landfills are a significant contributor to anthropogenic methane emissions, but measuring these emissions can be challenging. This work uses numerical simulations to assess the accuracy of the tracer dilution method, which is used to estimate landfill emissions. Atmospheric dispersion simulations with the Weather Research and Forecast model (WRF) are run over Sandtown Landfill in Delaware, USA, using observation data to validate the meteorological model output. A steady landfill methane emissions rate is used in the model, and methane and tracer gas concentrations are collected along various transects downwind from the landfill for use in the tracer dilution method. The calculated methane emissions are compared to the methane emissions rate used in the model to find the percent error of the tracer dilution method for each simulation. The roles of different factors are examined: measurement distance from the landfill, transect angle relative to the wind direction, speed of the transect vehicle, tracer placement relative to the hot spot of methane emissions, complexity of topography, and wind direction. Results show that percent error generally decreases with distance from the landfill, where the tracer and methane plumes become well mixed. Tracer placement has the largest effect on percent error, and topography and wind direction both have significant effects, with measurement errors ranging from -12% to 42% over all simulations. Transect angle and transect speed have small to negligible effects on the accuracy of the tracer dilution method. These tracer dilution method simulations provide insight into measurement errors that might occur in the field, enhance understanding of the method's limitations, and aid interpretation of field data. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Dose reduction in CT using bismuth shielding: measurements and Monte Carlo simulations.

    PubMed

    Chang, Kyung-Hwan; Lee, Wonho; Choo, Dong-Myung; Lee, Choon-Sik; Kim, Youhyun

    2010-03-01

    In this research, using direct measurements and Monte Carlo calculations, the potential dose reduction achieved by bismuth shielding in computed tomography was evaluated. The patient dose was measured using an ionisation chamber in a polymethylmethacrylate (PMMA) phantom that had five measurement points at the centre and periphery. Simulations were performed using the MCNPX code. For both the bare and the bismuth-shielded phantom, the differences of dose values between experiment and simulation were within 9%. The dose reductions due to the bismuth shielding were 1.2-55% depending on the measurement points, X-ray tube voltage and the type of shielding. The amount of dose reduction was significant for the positions covered by the bismuth shielding (34 - 46% for head and 41 - 55% for body phantom on average) and negligible for other peripheral positions. The artefact on the reconstructed images were minimal when the distance between the shielding and the organs was >1 cm, and hence the shielding should be selectively located to protect critical organs such as the eye lens, thyroid and breast. The simulation results using the PMMA phantom was compared with those using a realistically voxelised phantom (KTMAN-2). For eye and breast, the simulation results using the PMMA and KTMAN-2 phantoms were similar with each other, while for thyroid the simulation results were different due to the discrepancy of locations and the sizes of the phantoms. The dose reductions achieved by bismuth and lead shielding were compared with each other and the results showed that the difference of the dose reductions achieved by the two materials was less than 2-3%.

  11. KENNEDY SPACE CENTER, FLA. -- Sharon Edney, with Dynamac Corp., measures photosynthesis on Bibb lettuce being grown hydroponically for study in the Space Life Sciences Lab. The 100,000 square-foot facility houses labs for NASA’s ongoing research efforts, microbiology/microbial ecology studies and analytical chemistry labs. Also calling the new lab home are facilities for space flight-experiment and flight-hardware development, new plant growth chambers, and an Orbiter Environment Simulator that will be used to conduct ground control experiments in simulated flight conditions for space flight experiments. The SLS Lab, formerly known as the Space Experiment Research and Processing Laboratory or SERPL, provides space for NASA’s Life Sciences Services contractor Dynamac Corporation, Bionetics Corporation, and researchers from the University of Florida. NASA’s Office of Biological and Physical Research will use the facility for processing life sciences experiments that will be conducted on the International Space Station. The SLS Lab is the magnet facility for the International Space Research Park at KSC being developed in partnership with Florida Space Authority.

    NASA Image and Video Library

    2004-01-05

    KENNEDY SPACE CENTER, FLA. -- Sharon Edney, with Dynamac Corp., measures photosynthesis on Bibb lettuce being grown hydroponically for study in the Space Life Sciences Lab. The 100,000 square-foot facility houses labs for NASA’s ongoing research efforts, microbiology/microbial ecology studies and analytical chemistry labs. Also calling the new lab home are facilities for space flight-experiment and flight-hardware development, new plant growth chambers, and an Orbiter Environment Simulator that will be used to conduct ground control experiments in simulated flight conditions for space flight experiments. The SLS Lab, formerly known as the Space Experiment Research and Processing Laboratory or SERPL, provides space for NASA’s Life Sciences Services contractor Dynamac Corporation, Bionetics Corporation, and researchers from the University of Florida. NASA’s Office of Biological and Physical Research will use the facility for processing life sciences experiments that will be conducted on the International Space Station. The SLS Lab is the magnet facility for the International Space Research Park at KSC being developed in partnership with Florida Space Authority.

  12. An assessment of a software simulation tool for lidar atmosphere and ocean measurements

    NASA Astrophysics Data System (ADS)

    Powell, K. A.; Vaughan, M.; Burton, S. P.; Hair, J. W.; Hostetler, C. A.; Kowch, R. S.

    2014-12-01

    A high-fidelity lidar simulation tool is used to generate synthetic lidar backscatter data that closely matches the expected performance of various lidars, including the noise characteristics inherent to analog detection and uncertainties related to the measurement environment. This tool supports performance trade studies and scientific investigations for both the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP), which flies aboard Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO), and the NASA Langley Research Center airborne High Spectral Resolution Lidar (HSRL). CALIOP measures profiles of attenuated backscatter coefficients (532 and 1064 nm) and volume depolarization ratios at 532 nm. HSRL measures the same profiles plus volume depolarization at 1064 nm and a molecular-only profile which allows for the direct retrieval of aerosol extinction and backscatter profiles at 532 nm. The simulation tool models both the fundamental physics of the lidar instruments and the signals generated from aerosols, clouds, and the ocean surface and subsurface. This work presents the results of a study conducted to verify the accuracy of the simulated data using data from both HSRL and CALIOP. The tool was tuned to CALIOP instrument settings and the model atmosphere was defined using profiles of attenuated backscatter and depolarization obtained by HSRL during underflights of CALIPSO. The validated HSRL data provide highly accurate measurements of the particulate intensive and extensive optical properties and thus were considered as the truth atmosphere. The resulting simulated data were processed through the CALIPSO data analysis system. Comparisons showed good agreement between the simulated and CALIOP data. This verifies the accuracy of the tool to support studies involving the characterization of instrument components and advanced data analysis techniques. The capability of the tool to simulate ocean surface scattering and subsurface

  13. On the Use of Integrated Daylighting and Energy Simulations to Drive the Design of a Large Net-Zero Energy Office Building: Preprint

    SciTech Connect

    Guglielmetti, R.; Pless, S.; Torcellini, P.

    2010-08-01

    This paper illustrates the challenges of integrating rigorous daylight and electric lighting simulation data with whole-building energy models, and defends the need for such integration to achieve aggressive energy savings. Through a case study example, we examine the ways daylighting -- and daylighting simulation -- drove the design of a large net-zero energy project. We give a detailed review of the daylighting and electric lighting design process for the National Renewable Energy Laboratory's Research Support Facility (RSF), a 220,000 ft2 net-zero energy project the author worked on as a daylighting consultant. A review of the issues involved in simulating and validating the daylighting performance of the RSF will be detailed, including daylighting simulation, electric lighting control response, and integration of Radiance simulation data into the building energy model. Daylighting was a key strategy in reaching the contractual energy use goals for the RSF project; the building's program, layout, orientation and interior/furniture design were all influenced by the daylighting design, and simulation was critical in ensuring these many design components worked together in an integrated fashion, and would perform as required to meet a very aggressive energy performance goal, as expressed in a target energy use intensity.

  14. A Thorax Simulator for Complex Dynamic Bioimpedance Measurements With Textile Electrodes.

    PubMed

    Ulbrich, Mark; Muhlsteff, Jens; Teichmann, Daniel; Leonhardt, Steffen; Walter, Marian

    2015-06-01

    Bioimpedance measurements on the human thorax are suitable for assessment of body composition or hemodynamic parameters, such as stroke volume; they are non-invasive, easy in application and inexpensive. When targeting personal healthcare scenarios, the technology can be integrated into textiles to increase ease, comfort and coverage of measurements. Bioimpedance is generally measured using two electrodes injecting low alternating currents (0.5-10 mA) and two additional electrodes to measure the corresponding voltage drop. The impedance is measured either spectroscopically (bioimpedance spectroscopy, BIS) between 5 kHz and 1 MHz or continuously at a fixed frequency around 100 kHz (impedance cardiography, ICG). A thorax simulator is being developed for testing and calibration of bioimpedance devices and other new developments. For the first time, it is possible to mimic the complete time-variant properties of the thorax during an impedance measurement. This includes the dynamic real part and dynamic imaginary part of the impedance with a peak-to-peak value of 0.2 Ω and an adjustable base impedance (24.6 Ω ≥ Z0 ≥ 51.6 Ω). Another novelty is adjustable complex electrode-skin contact impedances for up to 8 electrodes to evaluate bioimpedance devices in combination with textile electrodes. In addition, an electrocardiographic signal is provided for cardiographic measurements which is used in ICG devices. This provides the possibility to generate physiologic impedance changes, and in combination with an ECG, all parameters of interest such as stroke volume (SV), pre-ejection period (PEP) or extracellular resistance (Re) can be simulated. The speed of all dynamic signals can be altered. The simulator was successfully tested with commercially available BIS and ICG devices and the preset signals are measured with high correlation (r = 0.996).

  15. Sensitivity study of large-scale particle image velocimetry measurement of river discharge using numerical simulation

    NASA Astrophysics Data System (ADS)

    Hauet, Alexandre; Creutin, Jean-Dominique; Belleudy, Philippe

    2008-01-01

    SummaryThis study deals with the uncertainty of large-scale particle image velocimetry (LSPIV) measurements in rivers. LSPIV belongs to the methods of local remote sensing of rivers, like Radar- and Lidar-based techniques. These methods have many potential advantages, in comparison with classical river gauging, but they have a fundamental drawback: they are indirect measurements. As such they need to be assessed in reference to direct measurements. A first validation method consists in the comparison of LSPIV measurements with classic gauging results, in field and laboratory experiments. Unfortunately, in both cases, it is impossible in practice to control all the parameters and to distinguish the impact of the various error sources. In the present study we propose a more theoretical assessment of LSPIV potential through numerical simulation. The idea is simply to mathematically formulate the present state of knowledge of the measurement including both the physics of the phenomenon (the illuminated river) and the physics of the sensor (the camera and the PIV tracking). The dilemma about when to start this type of simulation is the following: The simulation is satisfactory if we can validate it which means to be able to compare simulations and observations over a wide range of conditions. The simulation is useful to get preliminary insights about the most important measurement conditions to organize validation studies. Our simulator is composed of three blocks: The river block represents the unidirectional river flow by the association of the EDM model and a theoretical vertical velocity profile giving a 3D velocity distribution. This hydraulic model is complemented by features representing free surface tracers, the illumination of the free-surface (shadows and sun reflection) and the effect of the wind. The camera block transforms the river state parameters into raster images according to the intrinsic and extrinsic parameters of the camera. The LSPIV analysis

  16. Calibrated simulations of Z opacity experiments that reproduce the experimentally measured plasma conditions

    DOE PAGES

    Nagayama, T.; Bailey, J. E.; Loisel, G.; ...

    2016-02-05

    Recently, frequency-resolved iron opacity measurements at electron temperatures of 170–200 eV and electron densities of (0.7 – 4.0) × 1022 cm–3 revealed a 30–400% disagreement with the calculated opacities [J. E. Bailey et al., Nature (London) 517, 56 (2015)]. The discrepancies have a high impact on astrophysics, atomic physics, and high-energy density physics, and it is important to verify our understanding of the experimental platform with simulations. Reliable simulations are challenging because the temporal and spatial evolution of the source radiation and of the sample plasma are both complex and incompletely diagnosed. In this article, we describe simulations that reproducemore » the measured temperature and density in recent iron opacity experiments performed at the Sandia National Laboratories Z facility. The time-dependent spectral irradiance at the sample is estimated using the measured time- and space-dependent source radiation distribution, in situ source-to-sample distance measurements, and a three-dimensional (3D) view-factor code. The inferred spectral irradiance is used to drive 1D sample radiation hydrodynamics simulations. The images recorded by slit-imaged space-resolved spectrometers are modeled by solving radiation transport of the source radiation through the sample. We find that the same drive radiation time history successfully reproduces the measured plasma conditions for eight different opacity experiments. These results provide a quantitative physical explanation for the observed dependence of both temperature and density on the sample configuration. Simulated spectral images for the experiments without the FeMg sample show quantitative agreement with the measured spectral images. The agreement in spectral profile, spatial profile, and brightness provides further confidence in our understanding of the backlight-radiation time history and image formation. Furthermore, these simulations bridge the static-uniform picture of the

  17. Calibrated simulations of Z opacity experiments that reproduce the experimentally measured plasma conditions

    NASA Astrophysics Data System (ADS)

    Nagayama, T.; Bailey, J. E.; Loisel, G.; Rochau, G. A.; MacFarlane, J. J.; Golovkin, I.

    2016-02-01

    Recently, frequency-resolved iron opacity measurements at electron temperatures of 170-200 eV and electron densities of (0.7 - 4.0 )× 1022cm-3 revealed a 30 - 400 % disagreement with the calculated opacities [J. E. Bailey et al., Nature (London) 517, 56 (2015), 10.1038/nature14048]. The discrepancies have a high impact on astrophysics, atomic physics, and high-energy density physics, and it is important to verify our understanding of the experimental platform with simulations. Reliable simulations are challenging because the temporal and spatial evolution of the source radiation and of the sample plasma are both complex and incompletely diagnosed. In this article, we describe simulations that reproduce the measured temperature and density in recent iron opacity experiments performed at the Sandia National Laboratories Z facility. The time-dependent spectral irradiance at the sample is estimated using the measured time- and space-dependent source radiation distribution, in situ source-to-sample distance measurements, and a three-dimensional (3D) view-factor code. The inferred spectral irradiance is used to drive 1D sample radiation hydrodynamics simulations. The images recorded by slit-imaged space-resolved spectrometers are modeled by solving radiation transport of the source radiation through the sample. We find that the same drive radiation time history successfully reproduces the measured plasma conditions for eight different opacity experiments. These results provide a quantitative physical explanation for the observed dependence of both temperature and density on the sample configuration. Simulated spectral images for the experiments without the FeMg sample show quantitative agreement with the measured spectral images. The agreement in spectral profile, spatial profile, and brightness provides further confidence in our understanding of the backlight-radiation time history and image formation. These simulations bridge the static-uniform picture of the data

  18. Calibrated simulations of Z opacity experiments that reproduce the experimentally measured plasma conditions.

    PubMed

    Nagayama, T; Bailey, J E; Loisel, G; Rochau, G A; MacFarlane, J J; Golovkin, I

    2016-02-01

    Recently, frequency-resolved iron opacity measurements at electron temperatures of 170-200 eV and electron densities of (0.7-4.0)×10(22)cm(-3) revealed a 30-400% disagreement with the calculated opacities [J. E. Bailey et al., Nature (London) 517, 56 (2015)]. The discrepancies have a high impact on astrophysics, atomic physics, and high-energy density physics, and it is important to verify our understanding of the experimental platform with simulations. Reliable simulations are challenging because the temporal and spatial evolution of the source radiation and of the sample plasma are both complex and incompletely diagnosed. In this article, we describe simulations that reproduce the measured temperature and density in recent iron opacity experiments performed at the Sandia National Laboratories Z facility. The time-dependent spectral irradiance at the sample is estimated using the measured time- and space-dependent source radiation distribution, in situ source-to-sample distance measurements, and a three-dimensional (3D) view-factor code. The inferred spectral irradiance is used to drive 1D sample radiation hydrodynamics simulations. The images recorded by slit-imaged space-resolved spectrometers are modeled by solving radiation transport of the source radiation through the sample. We find that the same drive radiation time history successfully reproduces the measured plasma conditions for eight different opacity experiments. These results provide a quantitative physical explanation for the observed dependence of both temperature and density on the sample configuration. Simulated spectral images for the experiments without the FeMg sample show quantitative agreement with the measured spectral images. The agreement in spectral profile, spatial profile, and brightness provides further confidence in our understanding of the backlight-radiation time history and image formation. These simulations bridge the static-uniform picture of the data interpretation and the

  19. Simulation of complex glazing products; from optical data measurements to model based predictive controls

    SciTech Connect

    Kohler, Christian

    2012-04-01

    Complex glazing systems such as venetian blinds, fritted glass and woven shades require more detailed optical and thermal input data for their components than specular non light-redirecting glazing systems. Various methods for measuring these data sets are described in this paper. These data sets are used in multiple simulation tools to model the thermal and optical properties of complex glazing systems. The output from these tools can be used to generate simplified rating values or as an input to other simulation tools such as whole building annual energy programs, or lighting analysis tools. I also describe some of the challenges of creating a rating system for these products and which factors affect this rating. A potential future direction of simulation and building operations is model based predictive controls, where detailed computer models are run in real-time, receiving data for an actual building and providing control input to building elements such as shades.

  20. Comparison of Numerically Simulated and Experimentally Measured Performance of a Rotating Detonation Engine

    NASA Technical Reports Server (NTRS)

    Paxson, Daniel E.; Fotia, Matthew L.; Hoke, John; Schauer, Fred

    2015-01-01

    A quasi-two-dimensional, computational fluid dynamic (CFD) simulation of a rotating detonation engine (RDE) is described. The simulation operates in the detonation frame of reference and utilizes a relatively coarse grid such that only the essential primary flow field structure is captured. This construction and other simplifications yield rapidly converging, steady solutions. Viscous effects, and heat transfer effects are modeled using source terms. The effects of potential inlet flow reversals are modeled using boundary conditions. Results from the simulation are compared to measured data from an experimental RDE rig with a converging-diverging nozzle added. The comparison is favorable for the two operating points examined. The utility of the code as a performance optimization tool and a diagnostic tool are discussed.

  1. Numerical simulation and analysis of accurate blood oxygenation measurement by using optical resolution photoacoustic microscopy

    NASA Astrophysics Data System (ADS)

    Yu, Tianhao; Li, Qian; Li, Lin; Zhou, Chuanqing

    2016-10-01

    Accuracy of photoacoustic signal is the crux on measurement of oxygen saturation in functional photoacoustic imaging, which is influenced by factors such as defocus of laser beam, curve shape of large vessels and nonlinear saturation effect of optical absorption in biological tissues. We apply Monte Carlo model to simulate energy deposition in tissues and obtain photoacoustic signals reaching a simulated focused surface detector to investigate corresponding influence of these factors. We also apply compensation on photoacoustic imaging of in vivo cat cerebral cortex blood vessels, in which signals from different lateral positions of vessels are corrected based on simulation results. And this process on photoacoustic images can improve the smoothness and accuracy of oxygen saturation results.

  2. Application of Numerical Simulation and Vibration Measurements for Seismic Damage Assessment of Railway Structures

    NASA Astrophysics Data System (ADS)

    Uehan, Fumiaki; Meguro, Kimiro

    In this study, the authors discuss methods to assess the future/actual damage to RC structures by using numerical simulations and vibration measurements. First, the applicability of the Applied Element Method (AEM) is examined as an assessment tool for the seismic performance of RC structures with/without retrofit. Cyclic loading tests and seismic response of RC structures are simulated. Next, a method to improve the accuracy of vibration diagnoses of earthquake damaged RC structures is discussed by using damage assessment criteria calculated with the AEM. The AEM could simulate the damage behavior of RC columns, jacketed RC columns and an actual railway viaduct. The change of natural frequencies due to damage to RC columns and an actual railway viaduct with steel jacket were also correctly estimated. Seismic performance check of structures and development of assessment criteria for damage inspection can be effectively done by the AEM.

  3. Driver steering dynamics measured in car simulator under a range of visibility and roadmaking conditions

    NASA Technical Reports Server (NTRS)

    Allen, R. W.; Mcruer, D. T.

    1977-01-01

    A simulation experiment was conducted to determine the effect of reduced visibility on driver lateral (steering) control. The simulator included a real car cab and a single lane road image projected on a screen six feet in front of the driver. Simulated equations of motion controlled apparent car lane position in response to driver steering actions, wind gusts, and road curvature. Six drivers experienced a range of visibility conditions at various speeds with assorted roadmaking configurations (mark and gap lengths). Driver describing functions were measured and detailed parametric model fits were determined. A pursuit model employing a road curvature feedforward was very effective in explaining driver behavior in following randomly curving roads. Sampled-data concepts were also effective in explaining the combined effects of reduced visibility and intermittent road markings on the driver's dynamic time delay. The results indicate the relative importance of various perceptual variables as the visual input to the driver's steering control process is changed.

  4. Patient-specific simulations and measurements of the magneto-hemodynamic effect in human primary vessels.

    PubMed

    Kyriakou, Adamos; Neufeld, Esra; Szczerba, Dominik; Kainz, Wolfgang; Luechinger, Roger; Kozerke, Sebastian; McGregor, Robert; Kuster, Niels

    2012-02-01

    This paper investigates the main characteristics of the magneto-hemodynamic (MHD) response for application as a biomarker of vascular blood flow. The induced surface potential changes of a volunteer exposed to a 3 T static B0 field of a magnetic resonance imaging (MRI) magnet were measured over time at multiple locations by an electrocardiogram device and compared to simulation results. The flow simulations were based on boundary conditions derived from MRI flow measurements restricted to the aorta and vena cava. A dedicated and validated low-frequency electromagnetic solver was applied to determine the induced temporal surface potential change from the obtained 4D flow distribution using a detailed whole-body model of the volunteer. The simulated MHD signal agreed with major characteristics of the measured signal (temporal location of main peak, magnitude, variation across chest and along torso) except in the vicinity of the heart. The MHD signal is mostly influenced by the aorta; however, more vessels and better boundary conditions are needed to analyze the finer details of the response. The results show that the MHD signal is strongly position dependent with highly variable but reproducibly measurable distinguished characteristics. Additional investigations are necessary before determining whether the MHD effect is a reliable reference for location-specific information on blood flow.

  5. Measurements and time-domain simulations of multiphonics in the trombone.

    PubMed

    Velut, Lionel; Vergez, Christophe; Gilbert, Joël

    2016-10-01

    Multiphonic sounds of brass instruments are studied in this article. They are produced by playing a note on a brass instrument while simultaneously singing another note in the mouthpiece. This results in a peculiar sound, heard as a chord or a cluster of more than two notes in most cases. This effect is used in different artistic contexts. Measurements of the mouth pressure, the pressure inside the mouthpiece, and the radiated sound are recorded while a trombone player performs a multiphonic, first by playing an F3 and singing a C4, then playing an F3 and singing a note with a decreasing pitch. Results highlight the quasi-periodic nature of the multiphonic sound and the appearance of combination tones due to intermodulation between the played and the sung sounds. To assess the ability of a given brass instrument physical model to reproduce the measured phenomenon, time-domain simulations of multiphonics are carried out. A trombone model consisting in an exciter and a resonator nonlinearly coupled is forced while self-oscillating to reproduce simultaneous singing and playing. Comparison between simulated and measured signals is discussed. Spectral content of the simulated pressure match very well with the measured one, at the cost of a high forcing pressure.

  6. A Comparative Study of Simulated and Measured Gear-Flap Flow Interaction

    NASA Technical Reports Server (NTRS)

    Khorrami, Mehdi R.; Mineck, Raymond E.; Yao, Chungsheng; Jenkins, Luther N.; Fares, Ehab

    2015-01-01

    The ability of two CFD solvers to accurately characterize the transient, complex, interacting flowfield asso-ciated with a realistic gear-flap configuration is assessed via comparison of simulated flow with experimental measurements. The simulated results, obtained with NASA's FUN3D and Exa's PowerFLOW® for a high-fidelity, 18% scale semi-span model of a Gulfstream aircraft in landing configuration (39 deg flap deflection, main landing gear on and off) are compared to two-dimensional and stereo particle image velocimetry measurements taken within the gear-flap flow interaction region during wind tunnel tests of the model. As part of the bench-marking process, direct comparisons of the mean and fluctuating velocity fields are presented in the form of planar contour plots and extracted line profiles at measurement planes in various orientations stationed in the main gear wake. The measurement planes in the vicinity of the flap side edge and downstream of the flap trailing edge are used to highlight the effects of gear presence on tip vortex development and the ability of the computational tools to accurately capture such effects. The present study indicates that both computed datasets contain enough detail to construct a relatively accurate depiction of gear-flap flow interaction. Such a finding increases confidence in using the simulated volumetric flow solutions to examine the behavior of pertinent aer-odynamic mechanisms within the gear-flap interaction zone.

  7. Digital design and fabrication of simulation model for measuring orthodontic force.

    PubMed

    Liu, Yun-Feng; Zhang, Peng-Yuan; Zhang, Qiao-Fang; Zhang, Jian-Xing; Chen, Jie

    2014-01-01

    Three dimensional (3D) forces are the key factors for determining movement of teeth during orthodontic treatment. Designing precise forces and torques on tooth before treatment can result accurate tooth movements, but it is too difficult to realize. In orthodontic biomechanical systems, the periodontal tissues, including bones, teeth, and periodontal ligaments (PDL), are affected by braces, and measuring the forces applied on the teeth by braces should be based on a simulated model composed of these three types of tissues. This study explores the design and fabrication of a simulated oral model for 3D orthodontic force measurements. Based on medical image processing, tissue reconstruction, 3D printing, and PDL simulation and testing, a model for measuring force was designed and fabricated, which can potentially be used for force prediction, design of treatment plans, and precise clinical operation. The experiment illustrated that bi-component silicones with 2:8 ratios had similar mechanical properties to PDL, and with a positioning guide, the teeth were assembled in the mandible sockets accurately, and so a customized oral model for 3D orthodontic force measurement was created.

  8. Validation of MTF measurement for CBCT system using Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Hao, Ting; Gao, Feng; Zhao, Huijuan; Zhou, Zhongxing

    2016-03-01

    To evaluate the spatial resolution performance of cone beam computed tomography (CBCT) system, accurate measurement of the modulation transfer function (MTF) is required. This accuracy depends on the MTF measurement method and CBCT reconstruction algorithms. In this work, the accuracy of MTF measurement of CBCT system using wire phantom is validated by Monte Carlo simulation. A Monte Carlo simulation software tool BEAMnrc/EGSnrc was employed to model X-ray radiation beams and transport. Tungsten wires were simulated with different diameters and radial distances from the axis of rotation. We adopted filtered back projection technique to reconstruct images from 360° acquisition. The MTFs for four reconstruction kernels were measured from corresponding reconstructed wire images, while the ram-lak kernel increased the MTF relative to the cosine, hamming and hann kernel. The results demonstrated that the MTF degraded radially from the axis of rotation. This study suggested that an increase in the MTF for the CBCT system is possible by optimizing scanning settings and reconstruction parameters.

  9. Measurement of contact angles in a simulated microgravity environment generated by a large gradient magnetic field

    NASA Astrophysics Data System (ADS)

    Liu, Yong-Ming; Chen, Rui-Qing; Wu, Zi-Qing; Zhu, Jing; Shi, Jian-Yu; Lu, Hui-Meng; Shang, Peng; Yin, Da-Chuan

    2016-09-01

    The contact angle is an important parameter that is essential for studying interfacial phenomena. The contact angle can be measured using commercially available instruments. However, these well-developed instruments may not function or may be unsuitable for use in some special environments. A simulated microgravity generated by a large gradient magnetic field is such an environment in which the current measurement instruments cannot be installed. To measure the contact angle in this environment, new tools must be designed and manufactured to be compatible with the size and physical environment. In this study, we report the development and construction of a new setup that was specifically designed for use in a strong magnetic field to measure the contact angle between a levitated droplet and a solid surface. The application of the setup in a large gradient magnetic field was tested, and the contact angles were readily measured.

  10. Accuracy of flowmeters measuring horizontal groundwater flow in an unconsolidated aquifer simulator.

    USGS Publications Warehouse

    Bayless, E.R.; Mandell, Wayne A.; Ursic, James R.

    2011-01-01

    Borehole flowmeters that measure horizontal flow velocity and direction of groundwater flow are being increasingly applied to a wide variety of environmental problems. This study was carried out to evaluate the measurement accuracy of several types of flowmeters in an unconsolidated aquifer simulator. Flowmeter response to hydraulic gradient, aquifer properties, and well-screen construction was measured during 2003 and 2005 at the U.S. Geological Survey Hydrologic Instrumentation Facility in Bay St. Louis, Mississippi. The flowmeters tested included a commercially available heat-pulse flowmeter, an acoustic Doppler flowmeter, a scanning colloidal borescope flowmeter, and a fluid-conductivity logging system. Results of the study indicated that at least one flowmeter was capable of measuring borehole flow velocity and direction in most simulated conditions. The mean error in direction measurements ranged from 15.1 degrees to 23.5 degrees and the directional accuracy of all tested flowmeters improved with increasing hydraulic gradient. The range of Darcy velocities examined in this study ranged 4.3 to 155 ft/d. For many plots comparing the simulated and measured Darcy velocity, the squared correlation coefficient (r2) exceeded 0.92. The accuracy of velocity measurements varied with well construction and velocity magnitude. The use of horizontal flowmeters in environmental studies appears promising but applications may require more than one type of flowmeter to span the range of conditions encountered in the field. Interpreting flowmeter data from field settings may be complicated by geologic heterogeneity, preferential flow, vertical flow, constricted screen openings, and nonoptimal screen orientation.

  11. Validity and reliability of a three-dimensional dental cast simulator for arch dimension measurements.

    PubMed

    Nouri, Mahtab; Asefi, Sohrab; Baghban, Alireza Akbarzadeh; Aminian, Amin; Shamsa, Mohammad; Massudi, Reza

    2014-11-01

    The accuracy and reproducibility of measurements in a locally made three dimensional (3D) simulator was assessed and compared with manual caliper measurements. A total of 20 casts were scanned by our laser scanner. Software capabilities included dimensional measurements, transformation and rotation of the cast as a whole, separation and rotation of each tooth and clip far. Two orthodontists measured the intercanine width, intermolar width and canine, molar and arch depth on the casts and in 3D simulator. For calculating the reliability coefficient and comparing random and systematic errors between the two methods, intra-class correlation coefficient of reliability (ICC), Dahlberg and paired t-test were used, respectively. The ICC and Dahlberg's formula were also applied to assess intra-examiner and inter-examiner reliability of measurements on the casts and in the simulator (P < 0.05). Canine and molar depth measurements had low reliability on the casts. Reliability between methods for the remaining three variables was 0.87, 0.98 and 0.98 in the maxilla and 0.92, 0.77 and 0.94 in the mandible, respectively. The method error was between 0.31 and 0.48 mm. The mean intra-observer difference were 0.086 and 0.23 mm in the 3D method and caliper. The inter-observer differences were 0.21 and 0.42 mm, respectively. The maximum average absolute difference between the two methods was <0.5 mm, indicating that the new system is indeed clinically acceptable. The examiner reliability was higher in 3D measurements.

  12. UTILIZATION OF MULTIPLE MEASUREMENTS FOR GLOBAL THREE-DIMENSIONAL MAGNETOHYDRODYNAMIC SIMULATIONS

    SciTech Connect

    Wang, A. H.; Wu, S. T.; Tandberg-Hanssen, E.; Hill, Frank

    2011-05-01

    Magnetic field measurements, line of sight (LOS) and/or vector magnetograms, have been used in a variety of solar physics studies. Currently, the global transverse velocity measurements near the photosphere from the Global Oscillation Network Group (GONG) are available. We have utilized these multiple observational data, for the first time, to present a data-driven global three-dimensional and resistive magnetohydrodynamic (MHD) simulation, and to investigate the energy transport across the photosphere to the corona. The measurements of the LOS magnetic field and transverse velocity reflect the effects of convective zone dynamics and provide information from the sub-photosphere to the corona. In order to self-consistently include the observables on the lower boundary as the inputs to drive the model, a set of time-dependent boundary conditions is derived by using the method of characteristics. We selected GONG's global transverse velocity measurements of synoptic chart CR2009 near the photosphere and SOLIS full-resolution LOS magnetic field maps of synoptic chart CR2009 on the photosphere to simulate the equilibrium state and compute the energy transport across the photosphere. To show the advantage of using both observed magnetic field and transverse velocity data, we have studied two cases: (1) with the inputs of the LOS magnetic field and transverse velocity measurements, and (2) with the input of the LOS magnetic field and without the input of transverse velocity measurements. For these two cases, the simulation results presented here are a three-dimensional coronal magnetic field configuration, density distributions on the photosphere and at 1.5 solar radii, and the solar wind in the corona. The deduced physical characteristics are the total current helicity and the synthetic emission. By comparing all the physical parameters of case 1 and case 2 and their synthetic emission images with the EIT image, we find that using both the measured magnetic field and the

  13. Validity and reliability of a three-dimensional dental cast simulator for arch dimension measurements

    PubMed Central

    Nouri, Mahtab; Asefi, Sohrab; Baghban, Alireza Akbarzadeh; Aminian, Amin; Shamsa, Mohammad; Massudi, Reza

    2014-01-01

    Background: The accuracy and reproducibility of measurements in a locally made three dimensional (3D) simulator was assessed and compared with manual caliper measurements. Materials and Methods: A total of 20 casts were scanned by our laser scanner. Software capabilities included dimensional measurements, transformation and rotation of the cast as a whole, separation and rotation of each tooth and clip far. Two orthodontists measured the intercanine width, intermolar width and canine, molar and arch depth on the casts and in 3D simulator. For calculating the reliability coefficient and comparing random and systematic errors between the two methods, intra-class correlation coefficient of reliability (ICC), Dahlberg and paired t-test were used, respectively. The ICC and Dahlberg's formula were also applied to assess intra-examiner and inter-examiner reliability of measurements on the casts and in the simulator (P < 0.05). Results: Canine and molar depth measurements had low reliability on the casts. Reliability between methods for the remaining three variables was 0.87, 0.98 and 0.98 in the maxilla and 0.92, 0.77 and 0.94 in the mandible, respectively. The method error was between 0.31 and 0.48 mm. The mean intra-observer difference were 0.086 and 0.23 mm in the 3D method and caliper. The inter-observer differences were 0.21 and 0.42 mm, respectively. Conclusion: The maximum average absolute difference between the two methods was <0.5 mm, indicating that the new system is indeed clinically acceptable. The examiner reliability was higher in 3D measurements. PMID:25540660

  14. Extraction of cilium beat parameters by the combined application of photoelectric measurements and computer simulation.

    PubMed

    Gheber, L; Priel, Z

    1997-01-01

    Photoelectric signals were created and used to investigate the features of the signals as a function of the ciliary beat parameters. Moreover, correlation between the simulated and the measured signals permitted measurement of the cilium beat parameters. The simulations of the signals were based on generation of a series of time-frozen top-view frames of an active ciliary area and determination of the amount of light passing through an observation area in each of these frames. All the factors that might contribute to the shape of the signals, namely, partial ciliary transmittance of light, three-dimensional ciliary beat (composed of recovery, effective, and pause parts), phase distribution on the ciliary surface, and the large number of cilia that contribute to the photoelectric signal, were taken into account in generation of the signals. Changes in the ciliary parameters influenced the shape of the photoelectric signals, and the different phases of the beat could not be directly and unequivocally identified in the signals. The degree of temporal asymmetry of the beat and the portion of the cycle occupied by the pause significantly influenced the shapes of both the lower and the upper parts of the signal and the slopes of the signal. Increases in the angle of the arc swept by the cilium during the effective stroke smoothed the signals and increased the duration of the upper part of the signal. The angle of the arc projected by the cilium onto the cell surface during the recovery stroke had minor effects on the signal's shape. Characteristics of the metachronal wave also influenced the signal's shape markedly. Decreases in ciliary spacing smoothed the signals, whereas ciliary length had a minor influence on the simulated photoelectric signals. Comparison of the simulated and the measured signals showed that the beat parameters of the best-fitting simulated signals converged to values that agree well with the accepted range of beat parameters in mucociliary systems.

  15. Extraction of cilium beat parameters by the combined application of photoelectric measurements and computer simulation.

    PubMed Central

    Gheber, L; Priel, Z

    1997-01-01

    Photoelectric signals were created and used to investigate the features of the signals as a function of the ciliary beat parameters. Moreover, correlation between the simulated and the measured signals permitted measurement of the cilium beat parameters. The simulations of the signals were based on generation of a series of time-frozen top-view frames of an active ciliary area and determination of the amount of light passing through an observation area in each of these frames. All the factors that might contribute to the shape of the signals, namely, partial ciliary transmittance of light, three-dimensional ciliary beat (composed of recovery, effective, and pause parts), phase distribution on the ciliary surface, and the large number of cilia that contribute to the photoelectric signal, were taken into account in generation of the signals. Changes in the ciliary parameters influenced the shape of the photoelectric signals, and the different phases of the beat could not be directly and unequivocally identified in the signals. The degree of temporal asymmetry of the beat and the portion of the cycle occupied by the pause significantly influenced the shapes of both the lower and the upper parts of the signal and the slopes of the signal. Increases in the angle of the arc swept by the cilium during the effective stroke smoothed the signals and increased the duration of the upper part of the signal. The angle of the arc projected by the cilium onto the cell surface during the recovery stroke had minor effects on the signal's shape. Characteristics of the metachronal wave also influenced the signal's shape markedly. Decreases in ciliary spacing smoothed the signals, whereas ciliary length had a minor influence on the simulated photoelectric signals. Comparison of the simulated and the measured signals showed that the beat parameters of the best-fitting simulated signals converged to values that agree well with the accepted range of beat parameters in mucociliary systems

  16. Simulation of images of CDMAM phantom and the estimation of measurement uncertainties of threshold gold thickness.

    PubMed

    Mackenzie, Alistair; Eales, Timothy D; Dunn, Hannah L; Yip Braidley, Mary; Dance, David R; Young, Kenneth C

    2017-07-01

    To demonstrate a method of simulating mammography images of the CDMAM phantom and to investigate the coefficient of variation (CoV) in the threshold gold thickness (tT) measurements associated with use of the phantom. The noise and sharpness of Hologic Dimensions and GE Essential mammography systems were characterized to provide data for the simulation. The simulation method was validated by comparing the tT results of real and simulated images of the CDMAM phantom for three different doses and the two systems. The detection matrices produced from each of 64 images using CDCOM software were randomly resampled to create 512 sets of 8, 16 and 32 images to estimate the CoV of tT. Sets of simulated images for a range of doses were used to estimate the CoVs for a range of diameters and threshold thicknesses. No significant differences were found for tT or the CoV between real and simulated CDMAM images. It was shown that resampling from 256 images was required for estimating the CoV. The CoV was around 4% using 16 images for most of the phantom but is over double that for details near the edge of the phantom. We have demonstrated a method to simulate images of the CDMAM phantom for different systems at a range of doses. We provide data for calculating uncertainties in tT. Any future review of the European guidelines should take into consideration the calculated uncertainties for the 0.1mm detail. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  17. Ground return signal simulation and retrieval algorithm of spaceborne integrated path DIAL for CO2 measurements

    NASA Astrophysics Data System (ADS)

    Liu, Bing-Yi; Wang, Jun-Yang; Liu, Zhi-Shen

    2014-11-01

    Spaceborne integrated path differential absorption (IPDA) lidar is an active-detection system which is able to perform global CO2 measurement with high accuracy of 1ppmv at day and night over ground and clouds. To evaluate the detection performance of the system, simulation of the ground return signal and retrieval algorithm for CO2 concentration are presented in this paper. Ground return signals of spaceborne IPDA lidar under various ground surface reflectivity and atmospheric aerosol optical depths are simulated using given system parameters, standard atmosphere profiles and HITRAN database, which can be used as reference for determining system parameters. The simulated signals are further applied to the research on retrieval algorithm for CO2 concentration. The column-weighted dry air mixing ratio of CO2 denoted by XCO2 is obtained. As the deviations of XCO2 between the initial values for simulation and the results from retrieval algorithm are within the expected error ranges, it is proved that the simulation and retrieval algorithm are reliable.

  18. Simulation of decay processes and radiation transport times in radioactivity measurements

    NASA Astrophysics Data System (ADS)

    García-Toraño, E.; Peyres, V.; Bé, M.-M.; Dulieu, C.; Lépy, M.-C.; Salvat, F.

    2017-04-01

    The Fortran subroutine package PENNUC, which simulates random decay pathways of radioactive nuclides, is described. The decay scheme of the active nuclide is obtained from the NUCLEIDE database, whose web application has been complemented with the option of exporting nuclear decay data (possible nuclear transitions, branching ratios, type and energy of emitted particles) in a format that is readable by the simulation subroutines. In the case of beta emitters, the initial energy of the electron or positron is sampled from the theoretical Fermi spectrum. De-excitation of the atomic electron cloud following electron capture and internal conversion is described using transition probabilities from the LLNL Evaluated Atomic Data Library and empirical or calculated energies of released X rays and Auger electrons. The time evolution of radiation showers is determined by considering the lifetimes of nuclear and atomic levels, as well as radiation propagation times. Although PENNUC is designed to operate independently, here it is used in conjunction with the electron-photon transport code PENELOPE, and both together allow the simulation of experiments with radioactive sources in complex material structures consisting of homogeneous bodies limited by quadric surfaces. The reliability of these simulation tools is demonstrated through comparisons of simulated and measured energy spectra from radionuclides with complex multi-gamma spectra, nuclides with metastable levels in their decay pathways, nuclides with two daughters, and beta plus emitters.

  19. Three-dimensional simulation of ultrasound propagation through trabecular bone structures measured by synchrotron microtomography.

    PubMed

    Bossy, Emmanuel; Padilla, Frédéric; Peyrin, Françoise; Laugier, Pascal

    2005-12-07

    Three-dimensional numerical simulations of ultrasound transmission were performed through 31 trabecular bone samples measured by synchrotron microtomography. The synchrotron microtomography provided high resolution 3D mappings of bone structures, which were used as the input geometry in the simulation software developed in our laboratory. While absorption (i.e. the absorption of ultrasound through dissipative mechanisms) was not taken into account in the algorithm, the simulations reproduced major phenomena observed in real through-transmission experiments in trabecular bone. The simulated attenuation (i.e. the decrease of the transmitted ultrasonic energy) varies linearly with frequency in the MHz frequency range. Both the speed of sound (SOS) and the slope of the normalized frequency-dependent attenuation (nBUA) increase with the bone volume fraction. Twenty-five out of the thirty-one samples exhibited negative velocity dispersion. One sample was rotated to align the main orientation of the trabecular structure with the direction of ultrasonic propagation, leading to the observation of a fast and a slow wave. Coupling numerical simulation with real bone architecture therefore provides a powerful tool to investigate the physics of ultrasound propagation in trabecular structures. As an illustration, comparison between results obtained on bone modelled either as a fluid or a solid structure suggested the major role of mode conversion of the incident acoustic wave to shear waves in bone to explain the large contribution of scattering to the overall attenuation.

  20. Three-dimensional simulation of ultrasound propagation through trabecular bone structures measured by synchrotron microtomography

    NASA Astrophysics Data System (ADS)

    Bossy, Emmanuel; Padilla, Frédéric; Peyrin, Françoise; Laugier, Pascal

    2005-12-01

    Three-dimensional numerical simulations of ultrasound transmission were performed through 31 trabecular bone samples measured by synchrotron microtomography. The synchrotron microtomography provided high resolution 3D mappings of bone structures, which were used as the input geometry in the simulation software developed in our laboratory. While absorption (i.e. the absorption of ultrasound through dissipative mechanisms) was not taken into account in the algorithm, the simulations reproduced major phenomena observed in real through-transmission experiments in trabecular bone. The simulated attenuation (i.e. the decrease of the transmitted ultrasonic energy) varies linearly with frequency in the MHz frequency range. Both the speed of sound (SOS) and the slope of the normalized frequency-dependent attenuation (nBUA) increase with the bone volume fraction. Twenty-five out of the thirty-one samples exhibited negative velocity dispersion. One sample was rotated to align the main orientation of the trabecular structure with the direction of ultrasonic propagation, leading to the observation of a fast and a slow wave. Coupling numerical simulation with real bone architecture therefore provides a powerful tool to investigate the physics of ultrasound propagation in trabecular structures. As an illustration, comparison between results obtained on bone modelled either as a fluid or a solid structure suggested the major role of mode conversion of the incident acoustic wave to shear waves in bone to explain the large contribution of scattering to the overall attenuation.

  1. The method of infrared image simulation based on the measured image

    NASA Astrophysics Data System (ADS)

    Lou, Shuli; Liu, Liang; Ren, Jiancun

    2015-10-01

    The development of infrared imaging guidance technology has promoted the research of infrared imaging simulation technology and the key of infrared imaging simulation is the generation of IR image. The generation of IR image is worthful in military and economy. In order to solve the problem of credibility and economy of infrared scene generation, a method of infrared scene generation based on the measured image is proposed. Through researching on optical properties of ship-target and sea background, ship-target images with various gestures are extracted from recorded images based on digital image processing technology. The ship-target image is zoomed in and out to simulate the relative motion between the viewpoint and the target according to field of view and the distance between the target and the sensor. The gray scale of ship-target image is adjusted to simulate the radiation change of the ship-target according to the distance between the viewpoint and the target and the atmospheric transmission. Frames of recorded infrared images without target are interpolated to simulate high frame rate of missile. Processed ship-target images and sea-background infrared images are synthetized to obtain infrared scenes according to different viewpoints. Experiments proved that this method is flexible and applicable, and the fidelity and the reliability of synthesis infrared images can be guaranteed.

  2. Adsorption of acetaldehyde on ice as seen from computer simulation and infrared spectroscopy measurements.

    PubMed

    Darvas, Mária; Lasne, Jérôme; Laffon, Carine; Parent, Philippe; Picaud, Sylvain; Jedlovszky, Pál

    2012-03-06

    Detailed investigation of the adsorption of acetaldehyde on I(h) ice is performed under tropospheric conditions by means of grand canonical Monte Carlo computer simulations and compared to infrared spectroscopy measurements. The experimental and simulation results are in a clear accordance with each other. The simulations indicate that the adsorption process follows Langmuir behavior in the entire pressure range of the vapor phase of acetaldehyde. Further, it was found that the adsorption layer is strictly monomolecular, and the adsorbed acetaldehyde molecules are bound to the ice surface by only one hydrogen bond, typically formed with the dangling H atoms at the ice surface, in agreement with the experimental results. Besides this hydrogen bonding, at high surface coverages dipolar attraction between neighboring acetaldehyde molecules also contributes considerably to the energy gain of the adsorption. The acetaldehyde molecules adopt strongly tilted orientations relative to the ice surface, the tilt angle being scattered between 50° and 90° (i.e., perpendicular orientation). The range of the preferred tilt angles narrows, and the preference for perpendicular orientation becomes stronger upon saturation of the adsorption layer. The CH(3) group of the acetaldehyde molecules points as straight away from the ice surface within the constraint imposed by the tilt angle adopted by the molecule as possible. The heat of adsorption at infinitely low coverage is found to be -36 ± 2 kJ/mol from the infrared spectroscopy measurement, which is in excellent agreement with the computer simulation value of -34.1 kJ/mol.

  3. Macromolecular Crowding Studies of Amino Acids Using NMR Diffusion Measurements and Molecular Dynamics Simulations

    NASA Astrophysics Data System (ADS)

    Virk, Amninder; Stait-Gardner, Timothy; Willis, Scott; Torres, Allan; Price, William

    2015-02-01

    Molecular crowding occurs when the total concentration of macromolecular species in a solution is so high that a considerable proportion of the volume is physically occupied and therefore not accessible to other molecules. This results in significant changes in the solution properties of the molecules in such systems. Macromolecular crowding is ubiquitous in biological systems due to the generally high intracellular protein concentrations. The major hindrance to understanding crowding is the lack of direct comparison of experimental data with theoretical or simulated data. Self-diffusion is sensitive to changes in the molecular weight and shape of the diffusing species, and the available diffusion space (i.e., diffusive obstruction). Consequently, diffusion measurements are a direct means for probing crowded systems including the self-association of molecules. In this work, nuclear magnetic resonance measurements of the self-diffusion of four amino acids (glycine, alanine, valine and phenylalanine) up to their solubility limit in water were compared directly with molecular dynamics simulations. The experimental data were then analyzed using various models of aggregation and obstruction. Both experimental and simulated data revealed that the diffusion of both water and the amino acids were sensitive to the amino acid concentration. The direct comparison of the simulated and experimental data afforded greater insights into the aggregation and obstruction properties of each amino acid.

  4. Simulated and measured Hp(10) response of the personal dosemeter Seibersdorf.

    PubMed

    Hranitzky, C; Stadtmann, H

    2007-01-01

    The Hp(10) energy response of the personal dosemeter Seibersdorf and its two different filtered LiF:Mg,Ti (TLD-100) thermoluminescence (TL) detectors are investigated. A close-to-reality simulation model of the personal dosemeter badge including the wrapped detector card was implemented with the MCNP Monte Carlo N-particle transport code. The comparison of measured and computationally calculated response using a semi-empirical TL efficiency function is carried out to provide information about the quality of the results of both methods, experiment and simulation. Similar to the experimental calibration conditions, the irradiation of dosemeters centred on the front surface of the International Organization for Standardization (ISO) water slab phantom is simulated using ISO-4037 reference photon radiation qualities with mean energies between 24 keV and 1.25 MeV and corresponding ISO conversion coefficients. The comparison of the simulated and measured relative Hp(10) energy responses resulted in good agreement within some percent except for the filtered TL element at lower photon energies.

  5. Measuring Out-of-Time-Order Correlators on a Nuclear Magnetic Resonance Quantum Simulator

    NASA Astrophysics Data System (ADS)

    Li, Jun; Fan, Ruihua; Wang, Hengyan; Ye, Bingtian; Zeng, Bei; Zhai, Hui; Peng, Xinhua; Du, Jiangfeng

    2017-07-01

    The idea of the out-of-time-order correlator (OTOC) has recently emerged in the study of both condensed matter systems and gravitational systems. It not only plays a key role in investigating the holographic duality between a strongly interacting quantum system and a gravitational system, it also diagnoses the chaotic behavior of many-body quantum systems and characterizes information scrambling. Based on OTOCs, three different concepts—quantum chaos, holographic duality, and information scrambling—are found to be intimately related to each other. Despite its theoretical importance, the experimental measurement of the OTOC is quite challenging, and thus far there is no experimental measurement of the OTOC for local operators. Here, we report the measurement of OTOCs of local operators for an Ising spin chain on a nuclear magnetic resonance quantum simulator. We observe that the OTOC behaves differently in the integrable and nonintegrable cases. Based on the recent discovered relationship between OTOCs and the growth of entanglement entropy in the many-body system, we extract the entanglement entropy from the measured OTOCs, which clearly shows that the information entropy oscillates in time for integrable models and scrambles for nonintgrable models. With the measured OTOCs, we also obtain the experimental result of the butterfly velocity, which measures the speed of correlation propagation. Our experiment paves a way for experimentally studying quantum chaos, holographic duality, and information scrambling in many-body quantum systems with quantum simulators.

  6. Leasing physician office space.

    PubMed

    Murray, Charles

    2009-01-01

    When leasing office space, physicians should determine the effective lease rate (ELR) for each building they are considering before making a selection. The ELR is based on a number of factors, including building quality, building location, basic form of lease agreement, rent escalators and add-on factors in the lease, tenant improvement allowance, method of square footage measurement, quality of building management, and other variables. The ELR enables prospective physician tenants to accurately compare lease rates being quoted by building owners and to make leasing decisions based on objective criteria.

  7. Measurement and numerical simulation of a small centrifugal compressor characteristics at small or negative flow rate

    NASA Astrophysics Data System (ADS)

    Tsukamoto, Kaname; Okada, Mizuki; Inokuchi, Yuzo; Yamasaki, Nobuhiko; Yamagata, Akihiro

    2017-04-01

    For centrifugal compressors used in automotive turbochargers, the extension of the surge margin is demanded because of lower engine speed. In order to estimate the surge line exactly, it is required to acquire the compressor characteristics at small or negative flow rate. In this paper, measurement and numerical simulation of the characteristics at small or negative flow rate are carried out. In the measurement, an experimental facility with a valve immediately downstream of the compressor is used to suppress the surge. In the numerical work, a new boundary condition that specifies mass flow rate at the outlet boundary is used to simulate the characteristics around the zero flow rate region. Furthermore, flow field analyses at small or negative flow rate are performed with the numerical results. The separated and re-circulated flow fields are investigated by visualization to identify the origin of losses.

  8. Diagnostics of the Solar corona from Comparison Between Faraday Rotation Measurements and MHD Simulations

    NASA Astrophysics Data System (ADS)

    LE CHAT, G.; Kasper, J. C.; Cohen, O.; Spangler, S.

    2013-05-01

    Faraday rotation observations of natural radio sources allow remote diagnostics of the density and magnetic field of the solar corona. We use linear polarization observations made with the NRAO Very Large Array at frequencies of 1465 and 1665 MHz of 33 polarized radio sources occulted by the solar corona within 5 to 14 solar radii. The measurements were made during May 1997 (Mancuso and Spangler, 2000), March 2005 and april 2005 (Ingleby et al., 2005), corresponding to Carrington rotation number 1922, 1923, 2027 and 2028. We compare the observed Faraday rotation values with values extracted from MHD steady-state simulations of the solar corona using the BATS-R-US model. The simulations are driven by magnetogram data taken at the same time as the observed data. We present the agreement between the model and the Faraday rotation measurements, and we discuss the contraints imposed on models of the quiet corona and CMEs by these observations.

  9. Comparison of Simulated and Measured Fluid-Surface Oscillation Frequencies in a Channel

    NASA Astrophysics Data System (ADS)

    Trapuzzano, Matthew; Pierre, Kiesha; Tufekcioglu, Emre; Guldiken, Rasim; Tejada-Martinez, Andres; Crane, Nathan

    2016-11-01

    Many important processes from agriculture to manufacturing depend on the wetting of fluids on rough or textured surfaces. This has traditionally been studied from a macro-perspective. The effects of these surface features can be dramatically altered by vibrations that overcome energy barriers to contact line motion caused by surface roughness. In order to study these effects in confined geometries and at different length scales, a validated model is required. This presentation will compare the measured and simulated frequencies of capillary vibrations in a cylindrical glass tube. Fluid surface vibrations are excited externally through deformation of the interface. The resulting surface oscillations are observed with a high speed video camera and the dominant oscillation frequencies are calculated. The measured oscillation frequencies are compared to predictions from transient CFD simulations across a range of interface diameters from 400 um to 1.5 mm. These results may be used to inform studies of wetting under vibration. NSF CMMI-1361919.

  10. Simulation and Experimental Measurements of Inductively Coupled CF4 and CF4/Ar Plasmas

    NASA Technical Reports Server (NTRS)

    Hash, D. B.; Bose, D.; Rao, M. V. V. S.; Cruden, B. A.; Meyyappan, M.; Sharma, S. P.; Arnold, James O. (Technical Monitor)

    2000-01-01

    The recently developed code SEMS (semiconductor equipment modeling software)is applied to the simulation of CF4 and CF4/Ar inductively coupled plasmas (ICP). This work builds upon the earlier nitrogen, transformer coupled plasma (TCP) SEMS research by demonstrating its accuracy for more complex reactive mixtures, moving closer to the realization of a virtual plasma reactor. Attention is given to the etching of and/or formation of carbonaceous films on the quartz dielectric window and diagnostic aperatures. The simulations are validated through comparisons with experimental measurements using FTIR (Fourier Transform Infrared) and UV absorption spectroscopy for CFx and SiFx neutral radicals, QMS (quadrupole mass spectrometry) for the ions, and Langmuir probe measurements of electron number density and temperature in an ICP GEC reference cell.

  11. Measurements and numerical simulation of fabric evolution along the Talos Dome ice core, Antarctica

    NASA Astrophysics Data System (ADS)

    Montagnat, M.; Buiron, D.; Arnaud, L.; Broquet, A.; Schlitz, P.; Jacob, R.; Kipfstuhl, S.

    2012-12-01

    We present measurements of fabrics and microstructures made along the Talos Dome ice core, a core drilled in East Antarctica in the framework of the TALDICE project. Fabric and average grain size data are analyzed regarding changes in climatic conditions. In particular, the fabric strength increases sharply going downward from Holocene to Wisconsin ice. Following (Durand et al., 2007), this change is associated with a positive feedback between variations in ice viscosity, due to variations in dust content, and the impact of a shear stress component, increasing with depth. A ViscoPlastic Self-Consistent modeling approach is used to simulate the fabric evolution for a "perfect dome" configuration. The discrepancies between the measured and the simulated fabrics highlight the depth ranges where shear strongly affects the fabric strengthening. Finally, the grain size and fabric analyses show the occurrence of dynamic recrystallization mechanisms (continuous and discontinuous) along the core.

  12. Dosimetry in MARS spectral CT: TOPAS Monte Carlo simulations and ion chamber measurements.

    PubMed

    Lu, Gray; Marsh, Steven; Damet, Jerome; Carbonez, Pierre; Laban, John; Bateman, Christopher; Butler, Anthony; Butler, Phil

    2017-06-01

    Spectral computed tomography (CT) is an up and coming imaging modality which shows great promise in revealing unique diagnostic information. Because this imaging modality is based on X-ray CT, it is of utmost importance to study the radiation dose aspects of its use. This study reports on the implementation and evaluation of a Monte Carlo simulation tool using TOPAS for estimating dose in a pre-clinical spectral CT scanner known as the MARS scanner. Simulated estimates were compared with measurements from an ionization chamber. For a typical MARS scan, TOPAS estimated for a 30 mm diameter cylindrical phantom a CT dose index (CTDI) of 29.7 mGy; CTDI was measured by ion chamber to within 3% of TOPAS estimates. Although further development is required, our investigation of TOPAS for estimating MARS scan dosimetry has shown its potential for further study of spectral scanning protocols and dose to scanned objects.

  13. Simulation and Experimental Measurements of Inductively Coupled CF4 and CF4/Ar Plasmas

    NASA Technical Reports Server (NTRS)

    Hash, D. B.; Bose, D.; Rao, M. V. V. S.; Cruden, B. A.; Meyyappan, M.; Sharma, S. P.; Arnold, James O. (Technical Monitor)

    2000-01-01

    The recently developed code SEMS (semiconductor equipment modeling software)is applied to the simulation of CF4 and CF4/Ar inductively coupled plasmas (ICP). This work builds upon the earlier nitrogen, transformer coupled plasma (TCP) SEMS research by demonstrating its accuracy for more complex reactive mixtures, moving closer to the realization of a virtual plasma reactor. Attention is given to the etching of and/or formation of carbonaceous films on the quartz dielectric window and diagnostic aperatures. The simulations are validated through comparisons with experimental measurements using FTIR (Fourier Transform Infrared) and UV absorption spectroscopy for CFx and SiFx neutral radicals, QMS (quadrupole mass spectrometry) for the ions, and Langmuir probe measurements of electron number density and temperature in an ICP GEC reference cell.

  14. Analogue Materials Measured Under Simulated Lunar and Asteroid Environments: Application to Thermal Infrared Measurements of Airless Bodies

    NASA Astrophysics Data System (ADS)

    Donaldson Hanna, K. L.; Pieters, C. M.; Patterson, W., III; Moriarty, D.

    2012-12-01

    Remote sensing observations provide key insights into the composition and evolution of planetary surfaces. A fundamentally important component to any remote sensing study of planetary surfaces is laboratory measurements of well-characterized samples measured under the appropriate environmental conditions. The near-surface vacuum environment of airless bodies like the Moon and asteroids creates a thermal gradient in the upper hundred microns of regolith. Lab studies of particulate rocks and minerals as well as selected lunar soils under vacuum and lunar-like conditions have identified significant effects of this thermal gradient on thermal infrared (TIR) spectral measurements [e.g. Logan et al. 1973, Salisbury and Walter 1989, Thomas et al. 2010, Donaldson Hanna et al. 2012]. Compared to ambient conditions, these effects include: (1) the Christiansen feature (CF), an emissivity maximum diagnostic of mineralogy and average composition, shifts to higher wavenumbers and (2) an increase in spectral contrast of the CF relative to the Reststrahlen bands (RB), the fundamental molecular vibration bands due to Si-O stretching and bending. Such lab studies demonstrate the high sensitivity of TIR emissivity spectra to environmental conditions under which they are measured. The Asteroid and Lunar Environment Chamber (ALEC) is the newest addition to the RELAB at Brown University. The vacuum chamber simulates the space environment experienced by the near-surface soils of the Moon and asteroids. The internal rotation stage allows for six samples and two blackbodies to be measured without breaking vacuum (<10-4 mbar). Liquid nitrogen is used to cool the interior of the chamber, creating a cold, low emission environment (mimicking the space environment) for heated samples to radiate into. Sample cups can be heated in one of three configurations: (1) from below using heaters embedded in the base of the sample cup, (2) from above using a solar-like radiant heat source, and (3) from

  15. Measurement of Primary Ejecta From Normal Incident Hypervelocity Impact on Lunar Regolith Simulant

    NASA Technical Reports Server (NTRS)

    Edwards, David L.; Cooke, William; Moser, Danielle; Swift, Wesley

    2007-01-01

    The National Aeronautics and Space Administration (NASA) continues to make progress toward long-term lunar habitation. Critical to the design of a lunar habitat is an understanding of the lunar surface environment. A subject for further definition is the lunar primary ejecta environment. The document NASA SP-8013 was developed for the Apollo program and is the latest definition of the primary ejecta environment. There is concern that NASA SP-8013 may over-estimate the lunar primary ejecta environment. NASA's Meteoroid Environment Office (MEO) has initiated several tasks to improve the accuracy of our understanding of the lunar surface primary ejecta environment. This paper reports the results of experiments on projectile impact into pumice targets, simulating lunar regolith. The Ames Vertical Gun Range (AVGR) was used to accelerate spherical Pyrex projectiles of 0.29g to velocities ranging between 2.5 km/s and 5.18 km/s. Impact on the pumice target occurred at normal incidence. The ejected particles were detected by thin aluminum foil targets placed around the pumice target in a 0.5 Torr vacuum. A simplistic technique to characterize the ejected particles was formulated. Improvements to this technique will be discussed for implementation in future tests.

  16. Badge Office Process Analysis

    SciTech Connect

    Haurykiewicz, John Paul; Dinehart, Timothy Grant; Parker, Robert Young

    2016-05-12

    The purpose of this process analysis was to analyze the Badge Offices’ current processes from a systems perspective and consider ways of pursuing objectives set forth by SEC-PS, namely increased customer flow (throughput) and reduced customer wait times. Information for the analysis was gathered for the project primarily through Badge Office Subject Matter Experts (SMEs), and in-person observation of prevailing processes. Using the information gathered, a process simulation model was constructed to represent current operations and allow assessment of potential process changes relative to factors mentioned previously. The overall purpose of the analysis was to provide SEC-PS management with information and recommendations to serve as a basis for additional focused study and areas for potential process improvements in the future.

  17. Performance simulation of a spaceborne infrared coherent lidar for measuring tropospheric wind profiles.

    NASA Astrophysics Data System (ADS)

    Baron, Philippe; Ishii, Shoken; Kyoka, Gamo; Mizutani, Kohei; Chikako, Takahashi; Itabe, Toshikazu; Iwasaki, Toshiki; Kubota, Takuji; Okamoto, Kozo; Oki, Riko; Satoh, Masaki; Satoh, Yohei

    2014-05-01

    An effort has begun in Japan to develop a spaceborne instrument for measuring tropospheric winds. This project is a collaboration between the Japan Aerospace Exploration Agency (JAXA), the Meteorological Research Institute (MRI, Japan) and the National Institute of Information and Communications Technology (NICT, Japan) [1,2]. The aim is to measure the horizontal wind field in the troposphere on a global scale with a precision better than 3 ms-1, and a vertical and horizontal (along the satellite ground track) resolution better than 1 km and 100 km, respectively. In order to support the definition and the development of the instrument, an end-to-end simulator has been implemented including modules for i) simulating the time-dependent laser shot return power, ii) for averaging the spectral power of several returns and iii) for estimating the line-of-sight wind from the Doppler shift of the averaged spectra. The simulations take into account the satellite position and motion along the orbit track, the observational and instrumental characteristics, a 3-D representation of the relevant atmospheric parameters (i.e. wind field, cloud coverage and aerosols distribution) and the Earth surface characteristics. The simulator and the method for estimating the line-of-sight wind will be presented. We will show the results obtained for a payload composed of two 2-μm coherent LIDARs looking in orthogonal directions, and for a satellite moving on a low orbit. The precision, accuracy and the vertical and horizontal resolution of the wind estimates will be discussed. References: [1] S. Ishii, T. Iwasaki, M. Sato, R. Oki, K. Okamoto, T. Ishibashi, P. Baron, and T. Nishizawa, Future Doppler lidar wind measurement from space in Japan, Proc. of SPIE Vol. 8529, 2012 [2] S. Ishii, H. Iwai, K. Mizutani, P. Baron, T. Itabe, H. Fukuoka, T. Ishikawa, A. Sato and A. Asai, 2-μm coherent LIDAR for CO2 and wind measurements, Proc. of SPIE Vol. 8872, 2013

  18. GPS Radiation Measurements: Instrument Modeling and Simulation (Project w14_gpsradiation)

    SciTech Connect

    Sullivan, John P.

    2016-11-29

    The following topics are covered: electron response simulations and typical calculated response. Monte Carlo calculations of the response of future charged particle instruments (dosimeters) intended to measure the flux of charged particles in space were performed. The electron channels are called E1- E11 – each of which is intended to detect a different range of electron energies. These instruments are on current and future GPS satellites.

  19. Electro-optic and holographic measurement techniques for the atmospheric sciences. [considering spacecraft simulation applications

    NASA Technical Reports Server (NTRS)

    Moore, W. W., Jr.; Lemons, J. F.; Kurtz, R. L.; Liu, H.-K.

    1977-01-01

    A comprehensive examination is made of recent advanced research directions in the applications of electro-optical and holographic instrumentations and methods to atmospheric sciences problems. In addition, an overview is given of the in-house research program for environmental and atmospheric measurements with emphasis on particulates systems. Special treatment is made of the instrument methods and applications work in the areas of laser scattering spectrometers and pulsed holography sizing systems. Selected engineering tests data on space simulation chamber programs are discussed.

  20. Laser spectroscopic real time measurements of methanogenic activity under simulated Martian subsurface analog conditions

    NASA Astrophysics Data System (ADS)

    Schirmack, Janosch; Böhm, Michael; Brauer, Chris; Löhmannsröben, Hans-Gerd; de Vera, Jean-Pierre; Möhlmann, Diedrich; Wagner, Dirk

    2014-08-01

    On Earth, chemolithoautothrophic and anaerobic microorganisms such as methanogenic archaea are regarded as model organisms for possible subsurface life on Mars. For this reason, the methanogenic strain Methanosarcina soligelidi (formerly called Methanosarcina spec. SMA-21), isolated from permafrost-affected soil in northeast Siberia, has been tested under Martian thermo-physical conditions. In previous studies under simulated Martian conditions, high survival rates of these microorganisms were observed. In our study we present a method to measure methane production as a first attempt to study metabolic activity of methanogenic archaea during simulated conditions approaching conditions of Mars-like environments. To determine methanogenic activity, a measurement technique which is capable to measure the produced methane concentration with high precision and with high temporal resolution is needed. Although there are several methods to detect methane, only a few fulfill all the needed requirements to work within simulated extraterrestrial environments. We have chosen laser spectroscopy, which is a non-destructive technique that measures the methane concentration without sample taking and also can be run continuously. In our simulation, we detected methane production at temperatures down to -5 °C, which would be found on Mars either temporarily in the shallow subsurface or continually in the deep subsurface. The pressure of 50 kPa which we used in our experiments, corresponds to the expected pressure in the Martian near subsurface. Our new device proved to be fully functional and the results indicate that the possible existence of methanogenic archaea in Martian subsurface habitats cannot be ruled out.

  1. Nano-scale simulative measuring model for tapping mode atomic force microscopy and analysis for measuring a nano-scale ladder-shape standard sample.

    PubMed

    Lin, Zone-Ching; Chou, Ming-Ho

    2010-07-01

    This study proposes to construct a nano-scale simulative measuring model of Tapping Mode Atomic Force Microscopy (TM-AFM), compare with the edge effect of simulative and measurement results. It combines with the Morse potential and vibration theory to calculate the tip-sample atomic interaction force between probe and sample. Used Silicon atoms (Si) arrange the shape of the rectangular cantilever probe and the nano-scale ladder-shape standard sample atomic model. The simulative measurements are compared with the results for the simulative measurements and experimental measurement. It is found that the scan rate and the probe tip's bevel angle are the two reasons to cause the surface error and edge effect of measuring the nano-scale ladder-shape standard sample by TM-AFM. And the bevel angle is about equal to the probe tip's bevel angle from the results of simulated and experimented on the vertical section of the sample edge. To compare with the edge effect between the simulation and experimental measurement, its error is small. It could be verified that the constructed simulative measuring model for TM-AFM in this article is reasonable.

  2. Direct measurement of ammonia in simulated human breath using an inkjet-printed polyaniline nanoparticle sensor.

    PubMed

    Hibbard, Troy; Crowley, Karl; Killard, Anthony J

    2013-05-24

    A sensor fabricated from the inkjet-printed deposition of polyaniline nanoparticles onto a screen-printed silver interdigitated electrode was developed for the detection of ammonia in simulated human breath samples. Impedance analysis showed that exposure to ammonia gas could be measured at 962 Hz at which changes in resistance dominate due to the deprotonation of the polymer film. Sensors required minimal calibration and demonstrated excellent intra-electrode baseline drift (≤1.67%). Gases typically present in breath did not interfere with the sensor. Temperature and humidity were shown to have characteristic impedimetric and temporal effects on the sensor that could be distinguished from the response to ammonia. While impedance responses to ammonia could be detected from a single simulated breath, quantification was improved after the cumulative measurement of multiple breaths. The measurement of ammonia after 16 simulated breaths was linear in the range of 40-2175 ppbv (27-1514 μg m(-3)) (r(2)=0.9963) with a theoretical limit of detection of 6.2 ppbv (4.1 μg m(-3)) (SN(-1)=3).

  3. Mission Simulation of Space Lidar Measurements for Seasonal and Regional CO2 Variations

    NASA Technical Reports Server (NTRS)

    Kawa, Stephan; Collatz, G. J.; Mao, J.; Abshire, J. B.; Sun, X.; Weaver, C. J.

    2010-01-01

    Results of mission simulation studies are presented for a laser-based atmospheric [82 sounder. The simulations are based on real-time carbon cycle process modeling and data analysis. The mission concept corresponds to the Active Sensing of [82 over Nights, Days, and Seasons (ASCENDS) recommended by the US National Academy of Sciences Decadal Survey of Earth Science and Applications from Space. One prerequisite for meaningful quantitative sensor evaluation is realistic CO2 process modeling across a wide range of scales, i.e., does the model have representative spatial and temporal gradients? Examples of model comparison with data will be shown. Another requirement is a relatively complete description of the atmospheric and surface state, which we have obtained from meteorological data assimilation and satellite measurements from MODIS and [ALIPS0. We use radiative transfer model calculations, an instrument model with representative errors ' and a simple retrieval approach to complete the cycle from "nature" run to "pseudo-data" CO2, Several mission and instrument configuration options are examined/ and the sensitivity to key design variables is shown. We use the simulation framework to demonstrate that within reasonable technological assumptions for the system performance, relatively high measurement precision can be obtained, but errors depend strongly on environmental conditions as well as instrument specifications. Examples are also shown of how the resulting pseudo - measurements might be used to address key carbon cycle science questions.

  4. Comparison of CFD Simulations with Experimental Measurements of Nozzle Clogging in Continuous Casting of Steels

    NASA Astrophysics Data System (ADS)

    Mohammadi-Ghaleni, Mahdi; Asle Zaeem, Mohsen; Smith, Jeffrey D.; O'Malley, Ronald

    2016-12-01

    Measurements of clog deposit thickness on the interior surfaces of a commercial continuous casting nozzle are compared with computational fluid dynamics (CFD) predictions of melt flow patterns and particle-wall interactions to identify the mechanisms of nozzle clogging. A submerged entry nozzle received from industry was encased in epoxy and carefully sectioned to allow measurement of the deposit thickness on the internal surfaces of the nozzle. CFD simulations of melt flow patterns and particle behavior inside the nozzle were performed by combining the Eulerian-Lagrangian approach and detached eddy simulation turbulent model, matching the geometry and operating conditions of the industrial test. The CFD results indicated that convergent areas of the interior cross section of the nozzle increased the velocity and turbulence of the flowing steel inside the nozzle and decreased the clog deposit thickness locally in these areas. CFD simulations also predicted a higher rate of attachment of particles in the divergent area between two convergent sections of the nozzle, which matched the observations made in the industrial nozzle measurements.

  5. Self-report measures of distractibility as correlates of simulated driving performance.

    PubMed

    Kass, Steven J; Beede, Kristen E; Vodanovich, Stephen J

    2010-05-01

    The present study investigated the relationship between self-reported measures pertaining to attention difficulties and simulated driving performance while distracted. Thirty-six licensed drivers participated in a simulator driving task while engaged in a cell phone conversation. The participants completed questionnaires assessing their tendency toward boredom, cognitive failures, and behaviors associated with attention deficit and hyperactivity. Scores on these measures were significantly correlated with various driving outcomes (e.g., speed, lane maintenance, reaction time). Significant relationships were also found between one aspect of boredom proneness (i.e., inability to generate interest or concentrate) and self-reports of past driving behavior (moving violations). The current study may aid in the understanding of how individual differences in driver distractibility may contribute to unsafe driving behaviors and accident involvement. Additionally, such measures may assist in the identification of individuals at risk for committing driving errors due to being easily distracted. The benefits and limitations of conducting and interpreting simulation research are discussed. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  6. Microdosimetric Monte-Carlo Simulations and Measurements of Heavy Ion Irradiation of a TEPC

    NASA Astrophysics Data System (ADS)

    Rollet, S.; Beck, P.; Bock, F.; Ferrari, A.; Latocha, M.; Uchihori, Y.; Wind, M.

    Microdosimetric methods are well suited for systematic study and quantification of the absorbed energy spatial and temporal distribution in irradiated matter A standard instrument used to measure the energy dissipated in microscopic sites by individual ionizing events is the Tissue Equivalent Proportional Counter TEPC The main focus of this work is to examine interactions of heavy ions with tissue using both experimental and numerical methods Measurements with a TEPC instrument were carried out recently in heavy ion radiation fields at the Heavy Ion Medical Accelerator HIMAC facility in Chiba which belongs to the National Institute of Radiological Sciences NIRS in Japan The instrument has been exposed to two kinds of heavy ions under different irradiation geometries and beam parameters The heavy ions used were Oxygen with energy of 400 MeV u and Iron of 300 MeV u For the simulation of the irradiation experiments two Monte Carlo codes are used namely FLUKA and GEANT4 Both codes are widely used for basic research and applications in radiation protection and dosimetry radiobiology radiotherapy and space Besides scoring average quantities both Monte Carlo codes have the capability to score energy deposition on an event by event basis Thus together with the total energy deposition a simulation of microdosimetric spectra is possible The comparison of measured and simulated lineal energy distribution show a satisfactory agreement both for irradiation with Oxygen ions of 400 MeV u and for Iron ions of 300 MeV u We will discuss in detail the

  7. Measurement and FEM/BEM simulation of transverse effects in SAW resonators on lithium tantalate.

    PubMed

    Solal, Marc; Chen, Li; Gratier, Julien

    2013-11-01

    It is well known that transverse effects contribute significantly to the loss of SAW resonators on lithium tantalate. In particular, for frequencies above resonance, the surface wave is not guided inside the transducer and radiates into the busbars. In addition, because bulk modes can also be excited, scalar models are not sufficient to accurately predict transverse effects. It is also known that the layout of a SAW resonator (electrode gaps and dummy electrodes) has a strong impact on the transverse effects. In this paper, a periodic FEM/BEM model is presented and is used to simulate the transverse effects for various SAW resonator layouts. Test devices matching those simulated are fabricated and measured; the measured results are compared with the simulated results and show good agreement. By analyzing the dispersion curves produced from the FEM/BEM model in the different regions of the device, several frequency bands corresponding to different transverse behaviors are identified. These results are consistent with the elastic displacements, also computed by the FEM/BEM model. It is further shown that guided conditions in the gap between the transducer and the busbar occur for a frequency range above resonance. This result is in agreement with measurements showing that resonators with smaller gaps exhibit smaller spurious responses in their admittance.

  8. Simulations of an airborne laser absorption spectrometer for atmospheric CO2 measurements

    NASA Astrophysics Data System (ADS)

    Lin, B.; Ismail, S.; Harrison, F. W.; Browell, E. V.; Dobler, J. T.; Refaat, T.; Kooi, S. A.

    2012-12-01

    Atmospheric column amount of carbon dioxide (CO2), a major greenhouse gas of the atmosphere, has significantly increased from a preindustrial value of about 280 parts per million (ppm) to more than 390 ppm at present. Our knowledge about the spatiotemporal change and variability of the greenhouse gas, however, is limited. Thus, a near-term space mission of the Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) is crucial to increase our understanding of global sources and sinks of CO2. Currently, NASA Langley Research Center (LaRC) and ITT Exelis are jointly developing and testing an airborne laser absorption spectrometer (LAS) as a prototype instrument for the mission. To assess the space capability of accurate atmospheric CO2 measurements, accurate modeling of the instrument and practical evaluation of space applications are the keys for the success of the ASCENDS mission. This study discusses the simulations of the performance of the airborne instrument and its CO2 measurements. The LAS is a multi-wavelength spectrometer operating on a 1.57 um CO2 absorption line. The Intensity-Modulated Continuous-Wave (IM-CW) approach is implemented in the instrument. To reach accurate CO2 measurements, transmitted signals are monitored internally as reference channels. A model of this kind of instrument includes all major components of the spectrometer, such as modulation generator, fiber amplifier, telescope, detector, transimpedance amplifier, matched filter, and other signal processors. The characteristics of these components are based on actual laboratory tests, product specifications, and general understanding of the functionality of the components. For simulations of atmospheric CO2 measurements, environmental conditions related to surface reflection, atmospheric CO2 and H2O profiles, thin clouds, and aerosol layers, are introduced into the model. Furthermore, all major noise sources such as those from detectors, background radiation, speckle, and

  9. Influence of Assimilation of Subsurface Temperature Measurements on Simulations of Equatorial Undercurrent and South Equatorial Current Along the Pacific Equator

    NASA Technical Reports Server (NTRS)

    Halpern, David; Leetmaan, Ants; Reynolds, Richard W.; Ji, Ming

    1997-01-01

    Equatorial Pacific current and temperature fields were simulated with and without assimilation of subsurface temperature measurements for April 1992 - March 1995, and compared with moored bouy and research vessel current measurements.

  10. Influence of Assimilation of Subsurface Temperature Measurements on Simulations of Equatorial Undercurrent and South Equatorial Current Along the Pacific Equator

    NASA Technical Reports Server (NTRS)

    Halpern, David; Leetmaan, Ants; Reynolds, Richard W.; Ji, Ming

    1997-01-01

    Equatorial Pacific current and temperature fields were simulated with and without assimilation of subsurface temperature measurements for April 1992 - March 1995, and compared with moored bouy and research vessel current measurements.

  11. Estimation of primary pH measurement uncertainty using Monte Carlo simulation

    NASA Astrophysics Data System (ADS)

    Damasceno, J. C.; Borges, R. M. H.; Couto, P. R. G.; Ordine, A. P.; Getrouw, M. A.; Borges, P. P.; Fraga, I. C. S.

    2006-06-01

    pH is a widely used control parameter for several industrial processes. Thus, its correct determination and uncertainty estimation are extremely important. The Guide to the Expression of Uncertainty in Measurement (ISO-GUM) has been extensively used for pH uncertainty estimation. This work uses Monte Carlo simulation to estimate pH uncertainty in a primary pH system for the measurements of a regional comparison (SIM 8.11P-1) in which INMETRO has participated. The results are compared with the ISO-GUM analytical estimation approach and good agreement was found.

  12. Application of Geant4 simulation for analysis of soil carbon inelastic neutron scattering measurements.

    PubMed

    Yakubova, Galina; Kavetskiy, Aleksandr; Prior, Stephen A; Torbert, H Allen

    2016-07-01

    Inelastic neutron scattering (INS) was applied to determine soil carbon content. Due to non-uniform soil carbon depth distribution, the correlation between INS signals with some soil carbon content parameter is not obvious; however, a proportionality between INS signals and average carbon weight percent in ~10cm layer for any carbon depth profile is demonstrated using Monte-Carlo simulation (Geant4). Comparison of INS and dry combustion measurements confirms this conclusion. Thus, INS measurements give the value of this soil carbon parameter.

  13. A novel method for measuring the bending rigidity of model lipid membranes by simulating tethers.

    PubMed

    Harmandaris, Vagelis A; Deserno, Markus

    2006-11-28

    The tensile force along a cylindrical lipid bilayer tube is proportional to the membrane's bending modulus and inversely proportional to the tube radius. We show that this relation, which is experimentally exploited to measure bending rigidities, can be applied with even greater ease in computer simulations. Using a coarse-grained bilayer model we efficiently obtain bending rigidities that compare very well with complementary measurements based on an analysis of thermal undulation modes. We furthermore illustrate that no deviations from simple quadratic continuum theory occur up to a radius of curvature comparable to the bilayer thickness.

  14. Simulation and Measurement of Absorbed Dose from 137 Cs Gammas Using a Si Timepix Detector

    NASA Technical Reports Server (NTRS)

    Stoffle, Nicholas; Pinsky, Lawrence; Empl, Anton; Semones, Edward

    2011-01-01

    The TimePix readout chip is a hybrid pixel detector with over 65k independent pixel elements. Each pixel contains its own circuitry for charge collection, counting logic, and readout. When coupled with a Silicon detector layer, the Timepix chip is capable of measuring the charge, and thus energy, deposited in the Silicon. Measurements using a NIST traceable 137Cs gamma source have been made at Johnson Space Center using such a Si Timepix detector, and this data is compared to simulations of energy deposition in the Si layer carried out using FLUKA.

  15. Temperature distribution during RF ablation on ex vivo liver tissue: IR measurements and simulations

    NASA Astrophysics Data System (ADS)

    Macchi, Edoardo Gino; Gallati, Mario; Braschi, Giovanni; Cigada, Alfredo; Comolli, Lorenzo

    2015-05-01

    Radiofrequency thermal ablation is the first therapeutic option for the minimally invasive treatment of liver tumors. This medical procedure employs the Joule heat produced by a RF electromagnetic field to kill tumor cells. The outcome of the procedure is strongly affected by the temperature distribution near the RF applicator, however the measurement of this distribution, even in ex vivo experiments, is not straightforward since most traditional local temperature measurement techniques are not well-suited, due to both electromagnetic interferences and the sensor heat sink effect. Given the importance of the temperature field knowledge, in this paper special care was devoted to its measurement employing both infrared thermal imaging and NTC thermistors. Several RF ablation tests on ex vivo porcine liver tissue were carried out measuring the space-time evolution of temperature during the procedure (with spatial resolution ≤1 mm) and producing useful data for the design and the calibration of a numerical model. Electro-thermal numerical simulations of the experimental tests were performed using a mathematical model suitable for the heating phase of the procedure (up to 95 °C). The simulations results allowed to check the physical consistency of the measured data and suggested that a constant thermal conductivity is satisfactory for modeling the temperature evolution during RF ablation.

  16. Temperature distribution during RF ablation on ex vivo liver tissue: IR measurements and simulations

    NASA Astrophysics Data System (ADS)

    Macchi, Edoardo Gino; Gallati, Mario; Braschi, Giovanni; Cigada, Alfredo; Comolli, Lorenzo

    2014-09-01

    Radiofrequency thermal ablation is the first therapeutic option for the minimally invasive treatment of liver tumors. This medical procedure employs the Joule heat produced by a RF electromagnetic field to kill tumor cells. The outcome of the procedure is strongly affected by the temperature distribution near the RF applicator, however the measurement of this distribution, even in ex vivo experiments, is not straightforward since most traditional local temperature measurement techniques are not well-suited, due to both electromagnetic interferences and the sensor heat sink effect. Given the importance of the temperature field knowledge, in this paper special care was devoted to its measurement employing both infrared thermal imaging and NTC thermistors. Several RF ablation tests on ex vivo porcine liver tissue were carried out measuring the space-time evolution of temperature during the procedure (with spatial resolution ≤1 mm) and producing useful data for the design and the calibration of a numerical model. Electro-thermal numerical simulations of the experimental tests were performed using a mathematical model suitable for the heating phase of the procedure (up to 95 °C). The simulations results allowed to check the physical consistency of the measured data and suggested that a constant thermal conductivity is satisfactory for modeling the temperature evolution during RF ablation.

  17. Quantitative comparisons between experimentally measured 2-D carbon radiation and Monte Carlo impurity (MCI) code simulations

    SciTech Connect

    Evans, T.E.; Leonard, A.W.; West, W.P.; Finkenthal, D.F.; Fenstermacher, M.E.; Porter, G.D.

    1998-08-01

    Experimentally measured carbon line emissions and total radiated power distributions from the DIII-D divertor and Scrape-Off Layer (SOL) are compared to those calculated with the Monte Carlo Impurity (MCI) model. A UEDGE background plasma is used in MCI with the Roth and Garcia-Rosales (RG-R) chemical sputtering model and/or one of six physical sputtering models. While results from these simulations do not reproduce all of the features seen in the experimentally measured radiation patterns, the total radiated power calculated in MCI is in relatively good agreement with that measured by the DIII-D bolometric system when the Smith78 physical sputtering model is coupled to RG-R chemical sputtering in an unaltered UEDGE plasma. Alternatively, MCI simulations done with UEDGE background ion temperatures along the divertor target plates adjusted to better match those measured in the experiment resulted in three physical sputtering models which when coupled to the RG-R model gave a total radiated power that was within 10% of measured value.

  18. Two methods for transmission line simulation model creation based on time domain measurements

    NASA Astrophysics Data System (ADS)

    Rinas, D.; Frei, S.

    2011-07-01

    The emission from transmission lines plays an important role in the electromagnetic compatibility of automotive electronic systems. In a frequency range below 200 MHz radiation from cables is often the dominant emission factor. In higher frequency ranges radiation from PCBs and their housing becomes more relevant. Main sources for this emission are the conducting traces. The established field measurement methods according CISPR 25 for evaluation of emissions suffer from the need to use large anechoic chambers. Furthermore measurement data can not be used for simulation model creation in order to compute the overall fields radiated from a car. In this paper a method to determine the far-fields and a simulation model of radiating transmission lines, esp. cable bundles and conducting traces on planar structures, is proposed. The method measures the electromagnetic near-field above the test object. Measurements are done in time domain in order to get phase information and to reduce measurement time. On the basis of near-field data equivalent source identification can be done. Considering correlations between sources along each conductive structure in model creation process, the model accuracy increases and computational costs can be reduced.

  19. SAR measurement due to mobile phone exposure in a simulated biological media.

    PubMed

    Behari, J; Nirala, Jay Prakash

    2012-09-01

    The specific absorption rate (SAR) measurements are carried out for compliance testing of personal 3G Mobile phone. The accuracy of this experimental setup has been checked by comparing the SAR in 10 gm of simulated tissue and an arbitrary shaped box. This has been carried out using a 3G mobile Phone at 1718.5 MHz, in a medium simulating brain and muscle phantom. The SAR measurement system consists of a stepper motor to move a monopole E-field probe in two dimensions inside an arbitrary shaped box. The phantom is filled with appropriate frequency-specific fluids with measured electrical properties (dielectric constant and conductivity). That is close to the average for gray and white matters of the brain at the frequencies of interest (1718.5 MHz). Induced fields are measured using a specially designed monopole probe in its close vicinity. The probe is immersed in the phantom material. The measured data for induced fields are used to compute SAR values at various locations with respect to the mobile phone location. It is concluded that these SAR values are position dependent and well below the safety criteria prescribed for human exposure.

  20. Simulation of Statistical Fluctuations in the Spin Precession Measurements at RHIC

    SciTech Connect

    Poblaguev, A. A.

    2014-02-25

    Measurements of the driven spin coherent precession Sx(t)=Sx(0) - Sx(1) sin(ωt+φ0) were initiated in RHIC Run13. The expected value of the precession amplitude Sx(1) ~ 2 x 10-4 is about the statistical error in a single measurement and data fit gives a biased estimate of the Sx(1). For a proper statistical interpretation of the results of the several measurements, statistical fluctuations were studied using Monte-Carlo simulation. Preliminary results of the spin precession measurements in RHIC Run13 are presented.