Sample records for additional control experiments

  1. Controlling the extrudate swell in melt extrusion additive manufacturing of 3D scaffolds: a designed experiment.

    PubMed

    Yousefi, Azizeh-Mitra; Smucker, Byran; Naber, Alex; Wyrick, Cara; Shaw, Charles; Bennett, Katelyn; Szekely, Sarah; Focke, Carlie; Wood, Katherine A

    2018-02-01

    Tissue engineering using three-dimensional porous scaffolds has shown promise for the restoration of normal function in injured and diseased tissues and organs. Rigorous control over scaffold architecture in melt extrusion additive manufacturing is highly restricted mainly due to pronounced variations in the deposited strand diameter upon any variations in process conditions and polymer viscoelasticity. We have designed an I-optimal, split-plot experiment to study the extrudate swell in melt extrusion additive manufacturing and to control the scaffold architecture. The designed experiment was used to generate data to relate three responses (swell, density, and modulus) to a set of controllable factors (plotting needle diameter, temperature, pressure, and the dispensing speed). The fitted regression relationships were used to optimize the three responses simultaneously. The swell response was constrained to be close to 1 while maximizing the modulus and minimizing the density. Constraining the extrudate swell to 1 generates design-driven scaffolds, with strand diameters equal to the plotting needle diameter, and allows a greater control over scaffold pore size. Hence, the modulus of the scaffolds can be fully controlled by adjusting the in-plane distance between the deposited strands. To the extent of the model's validity, we can eliminate the effect of extrudate swell in designing these scaffolds, while targeting a range of porosity and modulus appropriate for bone tissue engineering. The result of this optimization was a predicted modulus of 14 MPa and a predicted density of 0.29 g/cm 3 (porosity ≈ 75%) using polycaprolactone as scaffold material. These predicted responses corresponded to factor levels of 0.6 μm for the plotting needle diameter, plotting pressure of 2.5 bar, melt temperature of 113.5 °C, and dispensing speed of 2 mm/s. The validation scaffold enabled us to quantify the percentage difference for the predictions, which was 9.5% for the

  2. French and English Together: An "Additive" Experience

    ERIC Educational Resources Information Center

    Wiltshire, Jessica; Harbon, Lesley

    2010-01-01

    This paper examines the nature of the "additive" experience of a bilingual French-English curriculum at Killarney Heights Public School in New South Wales. Predictably, the well-supported "additive" nature of the languages program model elicited positive reactions regarding educational success. The paper also explores issues…

  3. Controlled Detonation Dynamics in Additively Manufactured High Explosives

    NASA Astrophysics Data System (ADS)

    Schmalzer, Andrew; Tappan, Bryce; Bowden, Patrick; Manner, Virginia; Clements, Brad; Menikoff, Ralph; Ionita, Axinte; Branch, Brittany; Dattelbaum, Dana; Espy, Michelle; Patterson, Brian; Wu, Ruilian; Mueller, Alexander

    2017-06-01

    The effect of structure in explosives has long been a subject of interest to explosives engineers and scientists. Through structure, detonation dynamics in explosives can be manipulated, introducing a new level of safety and directed performance into these previously difficult to control materials. New advances in additive manufacturing (AM) allow the deliberate introduction of exact internal structures at dimensions approaching the mesoscale of these energetic materials. We show through simulation and experiment that this structure can be used to control detonation behavior by manipulating complex shockwave interactions. We use high-speed video and shorting mag-wires to determine the detonation velocity in AM generated explosive structures, demonstrating, for the first time, a method of controlling the directional propagation of reactive flow through the controlled introduction of structure within a high explosive. With ongoing improvement in the AM methods available coupled with guidance through modeling and simulations, more complex interactions are being explored. LANL LDRD Office.

  4. Active Dentate Granule Cells Encode Experience to Promote the Addition of Adult-Born Hippocampal Neurons

    PubMed Central

    Kirschen, Gregory W.; Shen, Jia; Wang, Jia; Man, Guoming; Wu, Song

    2017-01-01

    The continuous addition of new dentate granule cells (DGCs), which is regulated exquisitely by brain activity, renders the hippocampus plastic. However, how neural circuits encode experiences to affect the addition of adult-born neurons remains unknown. Here, we used endoscopic Ca2+ imaging to track the real-time activity of individual DGCs in freely behaving mice. For the first time, we found that active DGCs responded to a novel experience by increasing their Ca2+ event frequency preferentially. This elevated activity, which we found to be associated with object exploration, returned to baseline by 1 h in the same environment, but could be dishabituated via introduction to a novel environment. To transition seamlessly between environments, we next established a freely controllable virtual reality system for unrestrained mice. We again observed increased firing of active neurons in a virtual enriched environment. Interestingly, multiple novel virtual experiences increased the number of newborn neurons accumulatively compared with a single experience. Finally, optogenetic silencing of existing DGCs during novel environmental exploration perturbed experience-induced neuronal addition. Our study shows that the adult brain conveys novel, enriched experiences to increase the addition of adult-born hippocampal neurons by increasing the firing of active DGCs. SIGNIFICANCE STATEMENT Adult brains are constantly reshaping themselves from synapses to circuits as we encounter novel experiences from moment to moment. Importantly, this reshaping includes the addition of newborn hippocampal neurons. However, it remains largely unknown how our circuits encode experience-induced brain activity to govern the addition of new hippocampal neurons. By coupling in vivo Ca2+ imaging of dentate granule neurons with a novel, unrestrained virtual reality system for rodents, we discovered that a new experience increased firing of active dentate granule neurons rapidly and robustly

  5. Data acquisition and experiment control system of the project Maus (materials science experiments under weightlessness)

    NASA Astrophysics Data System (ADS)

    Lensch, D.

    In the context of Spacelab and Shuttle utilization, it is possible to conduct experiments in 'Small Self Contained Packages' (SSCP). This possibility exists primarily for experiments related to materials research/industrial processing engineering. The program involved is called 'get away special' (GAS). The project Maus was established in West Germany with the aim to participate in the program GAS. The autonomous design of the considered experiments made it necessary to develop an electronic unit for the control and the automatic conduction of the experiment. In addition, the process of the acquisition and the recording of the experimental data is also controlled.

  6. WebLab of a DC Motor Speed Control Didactical Experiment

    ERIC Educational Resources Information Center

    Bauer, Karine; Mendes, Luciano

    2012-01-01

    Purpose: Weblabs are an additional resource in the execution of experiments in control engineering education, making learning process more flexible both in time, by allowing extra class laboratory activities, and space, bringing the learning experience to remote locations where experimentation facilities would not be available. The purpose of this…

  7. Response of non-added solutes during nutrient addition experiments in streams

    NASA Astrophysics Data System (ADS)

    Rodriguez-Cardona, B.; Wymore, A.; Koenig, L.; Coble, A. A.; McDowell, W. H.

    2015-12-01

    Nutrient addition experiments, such as Tracer Additions for Spiraling Curve Characterization (TASCC), have become widely popular as a means to study nutrient uptake dynamics in stream ecosystems. However, the impact of these additions on ambient concentrations of non-added solutes is often overlooked. TASCC addition experiments are ideal for assessing interactions among solutes because it allows for the characterization of multiple solute concentrations across a broad range of added nutrient concentrations. TASCC additions also require the addition of a conservative tracer (NaCl) to track changes in conductivity during the experimental manipulation. Despite its use as a conservative tracer, chloride (Cl) and its associated sodium (Na) might change the concentrations of other ions and non-added nutrients through ion exchange or other processes. Similarly, additions of biologically active solutes might change the concentrations of other non-added solutes. These methodological issues in nutrient addition experiments have been poorly addressed in the literature. Here we examine the response of non-added solutes to pulse additions (i.e. TASCC) of NaCl plus nitrate (NO3-), ammonium, and phosphate across biomes including temperate and tropical forests, and arctic taiga. Preliminary results demonstrate that non-added solutes respond to changes in the concentration of these added nutrients. For example, concentrations of dissolved organic nitrogen (DON) in suburban headwater streams of New Hampshire both increase and decrease in response to NO3- additions, apparently due to biotic processes. Similarly, cations such as potassium, magnesium, and calcium also increase during TASCC experiments, likely due to cation exchange processes associated with Na addition. The response of non-added solutes to short-term pulses of added nutrients and tracers needs to be carefully assessed to ensure that nutrient uptake metrics are accurate, and to detect biotic interactions that may

  8. Patients' experiences of screening for type 2 diabetes: prospective qualitative study embedded in the ADDITION (Cambridge) randomised controlled trial

    PubMed Central

    Davies, Richard; Kinmonth, Ann-Louise; Griffin, Simon; Lawton, Julia

    2007-01-01

    Objectives To provide insight into factors that contribute to the anxiety reported in a quantitative study of the psychological effect of screening for type 2 diabetes. To explore expectations of and reactions to the screening experience of patients with positive, negative, and intermediate results. Design Prospective qualitative interview study of patients attending a screening programme for type 2 diabetes. Setting Seven general practices in the ADDITION (Cambridge) trial in the east of England. Participants 23 participants (aged 50-69) attending different stages in the screening process. Results Participants' perceptions changed as they progressed through the screening programme; the stepwise process seemed to help them adjust psychologically. The first screening test was typically considered unimportant and was attended with no thought about its implications. By the final diagnostic test, type 2 diabetes was considered a strong possibility, albeit a “mild” form. After diagnosis, people with screen detected type 2 diabetes tended to downplay its importance and talked confidently about their plans to control it. Participants with intermediate results seemed uncertain about their diagnosis, and those who screened negative were largely unaware of their remaining high risk. Conclusions This study helps in understanding the limited psychological impact of screening for type 2 diabetes quantified previously, in particular by the quantitative substudy of ADDITION (Cambridge). The findings have implications for implementing such a screening programme in terms of timing and content. PMID:17762000

  9. European isolation and confinement study. Additional experiments.

    PubMed

    Novara, M

    1993-01-01

    Microbiological Experiments. The ISEMSI microbiological contamination experiments confirmed known hypotheses, such as: the trend toward uniformity of skin microbial flora across a group of individuals enclosed together; the rather fast "colonization" of the environment by microorganisms shed by human inhabitants; and the heavy growth of microorganisms in poorly accessible and wet areas (toilets, air conditioning). In addition, possible disturbances of skin defense mechanisms against colonization by potentially pathogenic microbes were noted, as well as a difficulty in monitoring the microbial contents of the atmosphere (significant random variations occur between samples taken at different times and locations). Sensors for Atmospheric Contaminants. Several different prototypes of "array sensors" for the monitoring of trace gas contaminants in the atmosphere were evaluated during ISEMSI. Their performance was promising when compared with results achieved with a more conventional (and more complex) gas chromatograph/mass spectrometer device, also used during ISEMSI. An overall picture of the most important chemical contaminants to be found in enclosed, manned habitats (including contaminants produced by man himself) was obtained via the use of Tenax gas-adsorption traps. This permitted monitoring the fluctuation of contaminants on a daily basis, as well as during the complete 4-week period. Results will provide a valuable input for designing systems to monitor and control atmospheric contamination in future spacecraft. Particular attention was devoted to the monitoring of carbon monoxide in the chamber. Results showing the correlation between its concentration in the atmosphere and the percentage of carboxyhemoglobin in the EMSInauts' blood will allow the evaluation of the correctness of the presently specified maximum allowable concentration for spacecraft. Telemedicine Experiment. The telemedicine experiment confirmed the feasibility and importance of applying to a

  10. Research on width control of Metal Fused-coating Additive Manufacturing based on active control

    NASA Astrophysics Data System (ADS)

    Ren, Chuan qi; Wei, Zheng ying; Wang, Xin; Du, Jun; Zhang, Shan; Zhang, Zhitong; Bai, Hao

    2017-12-01

    Given the stability of the shape of the forming layer is one of the key problems that affect the final quality of the sample morphology, taking a study on the forming process and the control method of morphology make a significant difference to metal fused-coating additive manufacturing (MFCAM) in achieving the efficient and stable forming. To improve the quality and precision of the samples of single-layer single pass, a control method of morphology based on active control was established by this paper. The real-time acquisition of image was realized by CCD and the characteristics of morphology of the forming process were simultaneously extracted. Making analysis of the characteristics of the width during the process, the relationship between the relative difference of different frames and moving speed was given. A large number of experiments are used to verify the response speed and accuracy of the system. The results show that the active system can improve the morphology of the sample and the smoothness of the width of the single channel, and increase the uniformity of width by 55.16%.

  11. The Additive Effects of Choice and Control.

    ERIC Educational Resources Information Center

    Karbowski, Joseph; And Others

    In separate research studies, students who were given a choice of learning materials or who had control over aversive noise, demonstrated higher motivation and better task performance. To investigate the additive effects of choice and control on perception of control, 80 male and female college students participated in a 2 (choice vs. no-choice) X…

  12. Microcomputer Controlled Experiments.

    ERIC Educational Resources Information Center

    Kirkman, John; Knaggs, David

    1982-01-01

    Describes a microcomputer-controlled system which determines the current/voltage characteristics of a resistor, lamp, and diode, detailing system elements, construction, and providing printout of the program developed to provide control and arithmetic functions necessary to complete the experiment. (SK)

  13. Effect of metallic additives on in situ combustion of Huntington Beach crude experiments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baena, C.J.; Castanier, L.M.; Brigham, W.E.

    1990-08-01

    The economics and applicability of an in-situ combustion process for the recovery of crude oil are dictated to a large extent by the nature and the amount of fuel formed during the process. The aim of this work is to use combustion tube studies to determine on a quantitative basis, how the nature and the amount of fuel formed could be changed by the presence of metallic additives. These experiments follow from the qualitative observations on the effect of metallic additives on the in-situ combustion of Huntington Beach crude oil made by De los Rios (1987) at SUPRI. He performedmore » kinetic studies on the oxidation of Huntington Beach crude in porous media and showed that the nature of the fuel formed changed when metallic additives were present. Combustion tube runs were performed using the metallic additives: ferrous chloride (FeCl{sub 2{center dot}}4H{sub 2}O), zinc chloride (ZnCl{sub 2}) and stannic chloride (SnCl{sub 4{center dot}}5H{sub 2}O). Unconsolidated cores were prepared by mixing predetermined amounts of an aqueous solution of the metal salt, Huntington Beach crude oil, Ottawa sand and clay in order to achieve the desired fluid saturations. The mixture was then tamped into the combustion tube. Dry air combustion tube runs were performed keeping the conditions of saturation, air flux and injection pressure approximately the same during each run. The nature of the fuel formed and its impact on the combustion parameters were determined and compared with a control run -- an experiment performed with no metallic additive. 30 refs., 33 figs., 6 tabs.« less

  14. Additive QTLs on three chromosomes control flowering time in woodland strawberry (Fragaria vesca L.)

    PubMed Central

    Samad, Samia; Kurokura, Takeshi; Koskela, Elli; Toivainen, Tuomas; Patel, Vipul; Mouhu, Katriina; Sargent, Daniel James; Hytönen, Timo

    2017-01-01

    Flowering time is an important trait that affects survival, reproduction and yield in both wild and cultivated plants. Therefore, many studies have focused on the identification of flowering time quantitative trait locus (QTLs) in different crops, and molecular control of this trait has been extensively investigated in model species. Here we report the mapping of QTLs for flowering time and vegetative traits in a large woodland strawberry mapping population that was phenotyped both under field conditions and in a greenhouse after flower induction in the field. The greenhouse experiment revealed additive QTLs in three linkage groups (LG), two on both LG4 and LG7, and one on LG6 that explain about half of the flowering time variance in the population. Three of the QTLs were newly identified in this study, and one co-localized with the previously characterized FvTFL1 gene. An additional strong QTL corresponding to previously mapped PFRU was detected in both field and greenhouse experiments indicating that gene(s) in this locus can control the timing of flowering in different environments in addition to the duration of flowering and axillary bud differentiation to runners and branch crowns. Several putative flowering time genes were identified in these QTL regions that await functional validation. Our results indicate that a few major QTLs may control flowering time and axillary bud differentiation in strawberries. We suggest that the identification of causal genes in the diploid strawberry may enable fine tuning of flowering time and vegetative growth in the closely related octoploid cultivated strawberry. PMID:28580150

  15. Control of pyrite addition in coal liquefaction process

    DOEpatents

    Schmid, Bruce K.; Junkin, James E.

    1982-12-21

    Pyrite addition to a coal liquefaction process (22, 26) is controlled (118) in inverse proportion to the calcium content of the feed coal to maximize the C.sub.5 --900.degree. F. (482.degree. C.) liquid yield per unit weight of pyrite added (110). The pyrite addition is controlled in this manner so as to minimize the amount of pyrite used and thus reduce pyrite contribution to the slurry pumping load and disposal problems connected with pyrite produced slag.

  16. Tank Pressure Control Experiment (TPCE)

    NASA Technical Reports Server (NTRS)

    Bentz, Mike

    1992-01-01

    The Tank Pressure Control Experiment (TPCE) is a small self-contained STS payload designed to test a jet mixer for cryogenic fluid pressure control. Viewgraphs are presented that describe project organization, experiment objectives and approach, risk management, payload concept and mission plan, and initial test data.

  17. Grain Structure Control of Additively Manufactured Metallic Materials

    PubMed Central

    Faierson, Eric J.

    2017-01-01

    Grain structure control is challenging for metal additive manufacturing (AM). Grain structure optimization requires the control of grain morphology with grain size refinement, which can improve the mechanical properties of additive manufactured components. This work summarizes methods to promote fine equiaxed grains in both the additive manufacturing process and subsequent heat treatment. Influences of temperature gradient, solidification velocity and alloy composition on grain morphology are discussed. Equiaxed solidification is greatly promoted by introducing a high density of heterogeneous nucleation sites via powder rate control in the direct energy deposition (DED) technique or powder surface treatment for powder-bed techniques. Grain growth/coarsening during post-processing heat treatment can be restricted by presence of nano-scale oxide particles formed in-situ during AM. Grain refinement of martensitic steels can also be achieved by cyclic austenitizing in post-processing heat treatment. Evidently, new alloy powder design is another sustainable method enhancing the capability of AM for high-performance components with desirable microstructures.

  18. FACE computer simulation. [Flexible Arm Controls Experiment

    NASA Technical Reports Server (NTRS)

    Sadeh, Willy Z.; Szmyd, Jeffrey A.

    1990-01-01

    A computer simulation of the FACE (Flexible Arm Controls Experiment) was conducted to assess its design for use in the Space Shuttle. The FACE is supposed to be a 14-ft long articulate structure with 4 degrees of freedom, consisting of shoulder pitch and yaw, elbow pitch, and wrist pitch. Kinematics of the FACE was simulated to obtain data on arm operation, function, workspace and interaction. Payload capture ability was modeled. The simulation indicates the capability for detailed kinematic simulation and payload capture ability analysis, and the feasibility of real-time simulation was determined. In addition, the potential for interactive real-time training through integration of the simulation with various interface controllers was revealed. At this stage, the flexibility of the arm was not yet considered.

  19. MHD control experiments in the Extrap T2R Reversed Field Pinch

    NASA Astrophysics Data System (ADS)

    Marrelli, L.; Bolzonella, T.; Brunsell, P.; Cecconello, M.; Drake, J.; Franz, P.; Gregoratto, D.; Manduchi, G.; Martin, P.; Ortolani, S.; Paccagnella, R.; Piovesan, P.; Spizzo, G.; Yadikin, D.; Zanca, P.

    2004-11-01

    We report here on MHD active control experiments performed in the Extrap T2R device, which has been recently equipped with a set of 32 feedback controlled saddle coils couples. Experiments aiming at selectively exciting a resonant resistive instability in order to actively induce Quasi Single Helicity states will be presented. Open loop experiments have in fact shown that a spectrum with one dominant mode can be excited in a high aspect ratio device like T2R. In addition, evidences of controlled braking of tearing modes, which spontaneously rotate in T2R, have been gathered, allowing the determination of a threshold for mode wall locking. Different feedback control schemes have been implemented. In particular, mode suppression schemes proved successful in delaying resistive wall modes growth and in increasing the discharge duration: this suggests a hybrid mode control scenario, in which RWM are suppressed and QSH is induced. Radiation imaging and internal magnetic field reconstructions performed with the ORBIT code will be presented.

  20. Experiment-Based Teaching in Advanced Control Engineering

    ERIC Educational Resources Information Center

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

    2011-01-01

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

  1. Low-g fluid mixing - Further results from the Tank Pressure Control Experiment

    NASA Technical Reports Server (NTRS)

    Bentz, M. D.; Knoll, R. H.; Hasan, M. M.; Lin, C. S.

    1993-01-01

    The Tank Pressure Control Experiment (TPCE) made its first space flight on STS-43 in 1991. Its objective was to test the effectiveness of low-energy axial jet mixing at controlling pressures in low gravity. The experiment used refrigerant 113 at near-saturation conditions, at an 83 percent fill level, to simulate the fluid dynamics and thermodynamics of cryogenic fluids in future space applications. Results from this flight were reported previously. TPCE was again flown in space on STS-52 in 1992, this time primarily to study boiling and related thermal phenomena which will be reported elsewhere. However additional mixing and pressure control data were obtained from the reflight that supplement the data from the first flight.

  2. MxCuBE: a synchrotron beamline control environment customized for macromolecular crystallography experiments

    PubMed Central

    Gabadinho, José; Beteva, Antonia; Guijarro, Matias; Rey-Bakaikoa, Vicente; Spruce, Darren; Bowler, Matthew W.; Brockhauser, Sandor; Flot, David; Gordon, Elspeth J.; Hall, David R.; Lavault, Bernard; McCarthy, Andrew A.; McCarthy, Joanne; Mitchell, Edward; Monaco, Stéphanie; Mueller-Dieckmann, Christoph; Nurizzo, Didier; Ravelli, Raimond B. G.; Thibault, Xavier; Walsh, Martin A.; Leonard, Gordon A.; McSweeney, Sean M.

    2010-01-01

    The design and features of a beamline control software system for macromolecular crystallography (MX) experiments developed at the European Synchrotron Radiation Facility (ESRF) are described. This system, MxCuBE, allows users to easily and simply interact with beamline hardware components and provides automated routines for common tasks in the operation of a synchrotron beamline dedicated to experiments in MX. Additional functionality is provided through intuitive interfaces that enable the assessment of the diffraction characteristics of samples, experiment planning, automatic data collection and the on-line collection and analysis of X-ray emission spectra. The software can be run in a tandem client-server mode that allows for remote control and relevant experimental parameters and results are automatically logged in a relational database, ISPyB. MxCuBE is modular, flexible and extensible and is currently deployed on eight macromolecular crystallography beamlines at the ESRF. Additionally, the software is installed at MAX-lab beamline I911-3 and at BESSY beamline BL14.1. PMID:20724792

  3. SHEFEX II - Aerodynamic Re-Entry Controlled Sharp Edge Flight Experiment

    NASA Astrophysics Data System (ADS)

    Longo, J. M. A.; Turner, J.; Weihs, H.

    2009-01-01

    In this paper the basic goals and architecture of the SHEFEX II mission is presented. Also launched by a two staged sounding rocket system SHEFEX II is a consequent next step in technology test and demonstration. Considering all experience and collected flight data obtained during the SHEFEX I Mission, the test vehicle has been re-designed and extended by an active control system, which allows active aerodynamic control during the re-entry phase. Thus, ceramic based aerodynamic control elements like rudders, ailerons and flaps, mechanical actuators and an automatic electronic control unit has been implemented. Special focus is taken on improved GNC Elements. In addition, some other experiments including an actively cooled thermal protection element, advanced sensor equipment, high temperature antenna inserts etc. are part of the SHEFEX II experimental payload. A final 2 stage configuration has been selected considering Brazilian solid rocket boosters derived from the S 40 family. During the experiment phase a maximum entry velocity of Mach around 10 is expected for 50 seconds. Considering these flight conditions, the heat loads are not representative for a RLV re-entry, however, it allows to investigate the principal behaviour of such a facetted ceramic TPS, a sharp leading edge at the canards and fins and all associated gas flow effects and their structural response.

  4. Proppant flowback control additives

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nguyen, P.D.; Weaver, J.D.; Parker, M.A.

    1996-12-31

    This paper describes the laboratory and field development of thermoplastic film materials used to reduce proppant flowback that can occur after fracturing treatments. The paper provides a summary of flowback mechanism theories and laboratory tests comparing flowback tendency for various types of treating procedures and materials. Some of these materials include angular proppant, proppant/fiber mixtures, and proppant with film strips tested over a wide range of temperature, closure stress, and flow-rate conditions. Field treatment procedures are discussed, and several case histories are presented. All of the methods evaluated were effective in reducing proppant flowback under certain conditions. Heat-shrink film cutmore » into thin slivers proved to provide flowback reduction over broad temperature and closure stress ranges and was found to cause little impairment to fracture conductivity with some dependency on use concentration, temperature, and closure stress. The film materials were more resistant to damage caused by blending and pumping than all other materials evaluated. In addition, proppant packs, including consolidated packs, were significantly more tolerant of large, repeated stress changes. Field results indicate that the use of the heat-shrink film material as a flowback control agent permits more aggressive bean-up procedures following conventional fracturing treatments. Conventional dry-additive metering systems were used to add the film material to the fracturing fluid proppant slurry.« less

  5. 5. INTERIOR, INSTRUMENTATION AND CONTROL BUILDING ADDITION. Looking north. ...

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

    5. INTERIOR, INSTRUMENTATION AND CONTROL BUILDING ADDITION. Looking north. - Edwards Air Force Base, South Base Sled Track, Instrumentation & Control Building, South of Sled Track, Station "50" area, Lancaster, Los Angeles County, CA

  6. Chemical additive to enhance antimicrobial efficacy of chlorine and control cross-contamination during immersion chill of broiler carcasses.

    PubMed

    Schambach, B T; Berrang, M E; Harrison, M A; Meinersmann, R J

    2014-09-01

    Immersion chilling of broiler carcasses can be a site for cross-contamination between the occasional highly contaminated carcass and those that are co-chilled. Chlorine is often used as an antimicrobial but can be overcome by organic material. A proprietary chlorine stabilizer (T-128) based on phosphoric acid-propylene glycol was tested as a chill tank additive in experiments simulating commercial broiler chilling. In bench-scale experiments, 0.5% T-128 was compared with plain water (control), 50 ppm of chlorine, and the combination of 0.5% T-128 with 50 ppm of chlorine to control transfer of Salmonella and Campylobacter from inoculated wing drummettes to co-chilled uninoculated drummettes. Both chlorine and T-128 lessened cross-contamination with Salmonella (P < 0.05); T-128 and T-128 with chlorine were significantly more effective (P < 0.05) than the control or plain chlorine for control of Campylobacter. T-128 treatments were noted to have a pH of less than 4.0; an additional experiment demonstrated that the antimicrobial effect of T-128 was not due merely to a lower pH. In commercial broiler chilling, a pH close to 6.0 is preferred to maximize chlorine effectiveness, while maintaining water-holding capacity of the meat. In a set of pilot-scale experiments with T-128, a near-ideal pH of 6.3 was achieved by using tap water instead of the distilled water used in bench-scale experiments. Pilot-scale chill tanks were used to compare the combination of 0.5% T-128 and 50 ppm of chlorine with 50 ppm of plain chlorine for control of cross-contamination between whole carcasses inoculated with Salmonella and Campylobacter and co-chilled uninoculated carcasses. The T-128 treatment resulted in significantly less crosscontamination by either direct contact or water transfer with both organisms compared with plain chlorine treatment. T-128 may have use in commercial broiler processing to enhance the effectiveness of chlorine in processing water.

  7. Enhanced Attitude Control Experiment for SSTI Lewis Spacecraft

    NASA Technical Reports Server (NTRS)

    Maghami, Peoman G.

    1997-01-01

    The enhanced attitude control system experiment is a technology demonstration experiment on the NASA's small spacecraft technology initiative program's Lewis spacecraft to evaluate advanced attitude control strategies. The purpose of the enhanced attitude control system experiment is to evaluate the feasibility of designing and implementing robust multi-input/multi-output attitude control strategies for enhanced pointing performance of spacecraft to improve the quality of the measurements of the science instruments. Different control design strategies based on modern and robust control theories are being considered for the enhanced attitude control system experiment. This paper describes the experiment as well as the design and synthesis of a mixed H(sub 2)/H(sub infinity) controller for attitude control. The control synthesis uses a nonlinear programming technique to tune the controller parameters and impose robustness and performance constraints. Simulations are carried out to demonstrate the feasibility of the proposed attitude control design strategy. Introduction

  8. Additional experiments on flowability improvements of aviation fuels at low temperatures, volume 2

    NASA Technical Reports Server (NTRS)

    Stockemer, F. J.; Deane, R. L.

    1982-01-01

    An investigation was performed to study flow improver additives and scale-model fuel heating systems for use with aviation hydrocarbon fuel at low temperatures. Test were performed in a facility that simulated the heat transfer and temperature profiles anticipated in wing fuel tanks during flight of long-range commercial aircraft. The results are presented of experiments conducted in a test tank simulating a section of an outer wing integral fuel tank approximately full-scale in height, chilled through heat exchange panels bonded to the upper and lower horizontal surfaces. A separate system heated lubricating oil externally by a controllable electric heater, to transfer heat to fuel pumped from the test tank through an oil-to-fuel heat exchanger, and to recirculate the heated fuel back to the test tank.

  9. Performance anxiety experiences of professional ballet dancers: the importance of control.

    PubMed

    Walker, Imogen J; Nordin-Bates, Sanna M

    2010-01-01

    Performance anxiety research abounds in sport psychology, yet has been relatively sparse in dance. The present study explores ballet dancers' experiences of performance anxiety in relation to: 1. symptom type, intensity, and directional interpretation; 2. experience level (including company rank); and 3. self-confidence and psychological skills. Fifteen elite ballet dancers representing all ranks in one company were interviewed, and qualitative content analysis was conducted. Results revealed that cognitive anxiety was more dominant than somatic anxiety, and was unanimously interpreted as debilitative to performance. Somatic anxiety was more likely to be interpreted as facilitative, with the majority of dancers recognizing that a certain amount of anxiety could be beneficial to performance. Principal dancers suffered from higher intensities of performance anxiety than corps de ballet members. Feeling out of control emerged as a major theme in both the experience of anxiety and its interpretation. As a result, prevention or handling of anxiety symptoms may be accomplished by helping dancers to feel in control. Dancers may benefit from education about anxiety symptoms and their interpretation, in addition to psychological skills training incorporating cognitive restructuring strategies and problem-focussed coping to help increase their feelings of being in control.

  10. Anticipatory balance control is affected by loadless training experiences.

    PubMed

    Robert, G; Gueguen, N; Avogadro, P; Mouchnino, L

    2004-09-01

    The main purpose of this study was to identify whether a lot of sports training had any effect on the balance control associated with a leg movement. The nature of the training experience was also an important concern and we chose subject who had undergone specific training experience in absence of equilibrium constraints. To this end a comparison between control (untrained) subjects, triathletes and swimmers was designed to establish whether a general training in sports (triathletes) or a specific loadless training (swimmers), leads to differences in the balance control. A leg movement is preceded by a shift of the center of mass (CM) towards the supporting side to maintain equilibrium and forward to create the condition for progression. To provide an acceleration of the CM sideward and forward, an initial displacement of the center of pressure (CP) towards the moving limb and in posterior direction was performed. Interestingly, the lateral pressure onto the ground was greater increased in swimmers in both leg raising and obstacle avoidance tasks compared to the control group and/or triathletes whereas the backward CP shift in all group was the same. The initial control of the CM shift is very different in swimmers compared to triathletes and controls. The increased lateral pressure onto the ground in swimmers may be a result of a prolonged training in water. This suggests that prolonged training in the absence of equilibrium constraints has more of an effect on balance control than a prolonged general training. In addition, the lack of differences in the backward CP shift suggests that M/L and A/P controls support two functional goals: equilibrium maintenance and movement initiation.

  11. The Deep Impact Network Experiment Operations Center Monitor and Control System

    NASA Technical Reports Server (NTRS)

    Wang, Shin-Ywan (Cindy); Torgerson, J. Leigh; Schoolcraft, Joshua; Brenman, Yan

    2009-01-01

    The Interplanetary Overlay Network (ION) software at JPL is an implementation of Delay/Disruption Tolerant Networking (DTN) which has been proposed as an interplanetary protocol to support space communication. The JPL Deep Impact Network (DINET) is a technology development experiment intended to increase the technical readiness of the JPL implemented ION suite. The DINET Experiment Operations Center (EOC) developed by JPL's Protocol Technology Lab (PTL) was critical in accomplishing the experiment. EOC, containing all end nodes of simulated spaces and one administrative node, exercised publish and subscribe functions for payload data among all end nodes to verify the effectiveness of data exchange over ION protocol stacks. A Monitor and Control System was created and installed on the administrative node as a multi-tiered internet-based Web application to support the Deep Impact Network Experiment by allowing monitoring and analysis of the data delivery and statistics from ION. This Monitor and Control System includes the capability of receiving protocol status messages, classifying and storing status messages into a database from the ION simulation network, and providing web interfaces for viewing the live results in addition to interactive database queries.

  12. Thermal control surfaces experiment flight system performance

    NASA Technical Reports Server (NTRS)

    Wilkes, Donald R.; Hummer, Leigh L.; Zwiener, James M.

    1991-01-01

    The Thermal Control Surfaces Experiment (TCSE) is the most complex system, other than the LDEF, retrieved after long term space exposure. The TCSE is a microcosm of complex electro-optical payloads being developed and flow by NASA and the DoD including SDI. The objective of TCSE was to determine the effects of the near-Earth orbital environment and the LDEF induced environment on spacecraft thermal control surfaces. The TCSE was a comprehensive experiment that combined in-space measurements with extensive post flight analyses of thermal control surfaces to determine the effects of exposure to the low earth orbit space environment. The TCSE was the first space experiment to measure the optical properties of thermal control surfaces the way they are routinely measured in a lab. The performance of the TCSE confirms that low cost, complex experiment packages can be developed that perform well in space.

  13. Voices from the Classroom: Experiences of Teachers of Deaf Students with Additional Disabilities

    ERIC Educational Resources Information Center

    Musyoka, Millicent Malinda; Gentry, Mary Anne; Bartlett, James Joseph

    2016-01-01

    The purpose of this research is to investigate experiences of K-12 classroom teachers of deaf students with additional disabilities. Today, more deaf and hard of hearing students are identified as having additional disabilities (Bruce, DiNatale & Ford, 2008; Ewing, 2011; Gallaudet Research Institute, 2011; Jones, Jones & Ewing, 2006;…

  14. Modifications to the Langley 8-foot transonic pressure tunnel for the laminar flow control experiment

    NASA Technical Reports Server (NTRS)

    Harris, Charles D.; Brooks, Cuyler W., Jr.

    1988-01-01

    Modifications to the NASA Langley 8 Foot Transonic Pressure Tunnel in support of the Lamina Flow Control (LFC) Experiment included the installation of a honeymoon and five screens in the settling chamber upstream of the test section 41-long test section liner that extended from the upstream end of the test section contraction region, through the best section, and into the diffuser. The honeycomb and screens were installed as permanent additions to the facility, and the liner was a temporary addition to be removed at the conclusion of the LFC Experiment. These modifications are briefly described.

  15. Insulin-loaded biodegradable PLGA microcapsules: initial burst release controlled by hydrophilic additives.

    PubMed

    Yamaguchi, Y; Takenaga, M; Kitagawa, A; Ogawa, Y; Mizushima, Y; Igarashi, R

    2002-06-17

    We investigated the controlled release of human insulin at an initial stage from poly(DL-lactic-co-glycolic acid) (PLGA, M(w) 6600) spherical matrices. PLGA microcapsules were prepared by the novel solvent evaporation multiple emulsion process. When the crystalline insulin was dispersed in dichloromethane as solid-in-oil (S/O) dispersion, it was found that most of insulin molecules were inlaid on the surface of PLGA microcapsules. Consequently, insulin-loaded PLGA microcapsules exhibited marked rapid release of insulin within several hours in both in vivo and in vitro experiments. On the other hand, the addition of glycerol or water in the primary dichloromethane dispersion results in drastically suppressed initial release. It was found by SEM observation that water- or glycerol-in-oil (W/O or G/O) type mini-emulsion droplets with a mean diameter of 300-500 nm were formed in this primary solution. This phenomenon can be theoretically presumed to occur because insulin and PLGA molecules, having amphiphilic properties, converge on the interface between the hydrophilic additive and dichloromethane. Hence, insulin molecules heterogeneously located in the inside of PLGA microcapsules, not on the surface, would be gradually released with PLGA hydrolytic decomposition. As an additional effect of glycerol, the initial burst was further suppressed due to the decrease of the glass transition temperature of PLGA from 42.5 to 36.7 degrees C. Since the annealing of PLGA molecules took place at around 37 degrees C, the porous structure of microspheres immediately disappeared after immersion in PBS or subcutaneous administration. The insulin diffusion through the water-filled pores would be effectively prevented. The strict controlled initial release of insulin from the PLGA microsphere suggested the possibility of utilization in insulin therapy for type I diabetic patients who need construction of a basal insulin profile.

  16. Public participation in wilderness and backcountry litter control: a review of research and management experience.

    Treesearch

    Robert M. Muth; Roger N. Clark

    1978-01-01

    This paper describes the application of the Incentive System for Litter Control to wilderness and backcountry environments. Based on research, observation, and management experience, a set of procedures was developed and is presented here. Additional management considerations are discussed.

  17. Reusable experiment controllers, case studies

    NASA Astrophysics Data System (ADS)

    Buckley, Brian A.; Gaasbeck, Jim Van

    1996-03-01

    Congress has given NASA and the science community a reality check. The tight and ever shrinking budgets are trimming the fat from many space science programs. No longer can a Principal Investigator (PI) afford to waste development dollars on re-inventing spacecraft controllers, experiment/payload controllers, ground control systems, or test sets. Inheritance of the Ground Support Equipment (GSE) from one program to another is not a significant re-use of technology to develop a science mission in these times. Reduction of operational staff and highly autonomous experiments are needed to reduce the sustaining cost of a mission. The re-use of an infrastructure from one program to another is needed to truly attain the cost and time savings required. Interface and Control Systems, Inc. (ICS) has a long history of re-usable software. Navy, Air Force, and NASA programs have benefited from the re-use of a common control system from program to program. Several standardization efforts in the AIAA have adopted the Spacecraft Command Language (SCL) architecture as a point solution to satisfy requirements for re-use and autonomy. The Environmental Research Institute of Michigan (ERIM) has been a long-standing customer of ICS and are working on their 4th generation system using SCL. Much of the hardware and software infrastructure has been re-used from mission to mission with little cost for re-hosting a new experiment. The same software infrastructure has successfully been used on Clementine, and an end-to-end system is being deployed for the Far Ultraviolet Spectroscopic Explorer (FUSE) for Johns Hopkins University. A case study of the ERIM programs, Clementine and FUSE will be detailed in this paper.

  18. Wavefront Control Testbed (WCT) Experiment Results

    NASA Technical Reports Server (NTRS)

    Burns, Laura A.; Basinger, Scott A.; Campion, Scott D.; Faust, Jessica A.; Feinberg, Lee D.; Hayden, William L.; Lowman, Andrew E.; Ohara, Catherine M.; Petrone, Peter P., III

    2004-01-01

    The Wavefront Control Testbed (WCT) was created to develop and test wavefront sensing and control algorithms and software for the segmented James Webb Space Telescope (JWST). Last year, we changed the system configuration from three sparse aperture segments to a filled aperture with three pie shaped segments. With this upgrade we have performed experiments on fine phasing with line-of-sight and segment-to-segment jitter, dispersed fringe visibility and grism angle;. high dynamic range tilt sensing; coarse phasing with large aberrations, and sampled sub-aperture testing. This paper reviews the results of these experiments.

  19. Middeck Active Control Experiment (MACE), phase A

    NASA Technical Reports Server (NTRS)

    Crawley, Edward F.; Deluis, Javier; Miller, David W.

    1989-01-01

    A rationale to determine which structural experiments are sufficient to verify the design of structures employing Controlled Structures Technology was derived. A survey of proposed NASA missions was undertaken to identify candidate test articles for use in the Middeck Active Control Experiment (MACE). The survey revealed that potential test articles could be classified into one of three roles: development, demonstration, and qualification, depending on the maturity of the technology and the mission the structure must fulfill. A set of criteria was derived that allowed determination of which role a potential test article must fulfill. A review of the capabilities and limitations of the STS middeck was conducted. A reference design for the MACE test article was presented. Computing requirements for running typical closed-loop controllers was determined, and various computer configurations were studied. The various components required to manufacture the structure were identified. A management plan was established for the remainder of the program experiment development, flight and ground systems development, and integration to the carrier. Procedures for configuration control, fiscal control, and safety, reliabilty, and quality assurance were developed.

  20. Police arrest and self-defence skills: performance under anxiety of officers with and without additional experience in martial arts.

    PubMed

    Renden, Peter G; Landman, Annemarie; Savelsbergh, Geert J P; Oudejans, Raôul R D

    2015-01-01

    We investigated whether officers with additional martial arts training experience performed better in arrest and self-defence scenarios under low and high anxiety and were better able to maintain performance under high anxiety than officers who just rely on regular police training. We were especially interested to find out whether training once a week would already lead to better performance under high anxiety. Officers with additional experience in kickboxing or karate/jiu-jitsu (training several times per week), or krav maga (training once a week) and officers with no additional experience performed several arrest and self-defence skills under low and high anxiety. Results showed that officers with additional experience (also those who trained once a week) performed better under high anxiety than officers with no additional experience. Still, the additional experience did not prevent these participants from performing worse under high anxiety compared to low anxiety. Implications for training are discussed. Practitioner summary: Dutch police officers train their arrest and self-defence skills only four to six hours per year. Our results indicate that doing an additional martial arts training once a week may lead to better performance under anxiety, although it cannot prevent that performance decreases under high anxiety compared to low anxiety.

  1. Thermal control surfaces experiment: Initial flight data analysis

    NASA Technical Reports Server (NTRS)

    Wilkes, Donald R.; Hummer, Leigh L.

    1991-01-01

    The behavior of materials in the space environment continues to be a limiting technology for spacecraft and experiments. The thermal control surfaces experiment (TCSE) aboard the Long Duration Exposure Facility (LDEF) is the most comprehensive experiment flown to study the effects of the space environment on thermal control surfaces. Selected thermal control surfaces were exposed to the LDEF orbital environment and the effects of this exposure were measured. The TCSE combined in-space orbital measurements with pre and post-flight analyses of flight materials to determine the effects of long term space exposure. The TCSE experiment objective, method, and measurements are described along with the results of the initial materials analysis. The TCSE flight system and its excellent performance on the LDEF mission is described. A few operational anomalies were encountered and are discussed.

  2. A feasibility study of orbiter flight control experiments

    NASA Technical Reports Server (NTRS)

    Geissler, W. H.

    1978-01-01

    The results of a feasibility study of orbiter flight control experiments performed are summarized. Feasibility studies were performed on a group of 14 experiments selected from a candidate list of 35 submitted to the study contractor by the flight control community. Concepts and requirements were developed for the 14 selected experiments and they were ranked on a basis of technical value, feasibility, and cost. It was concluded that all the selected experiments can be considered as potential candidates for the Orbiter Experiment program, which is being formulated for the Orbiter Flight Tests and subsequent operational flights, regardless of the relative ranking established during the study. None of the selected experiments has significant safety implications and the cost of most was estimated to be less than $200K.

  3. Antagonistic control of a dual-input mammalian gene switch by food additives.

    PubMed

    Xie, Mingqi; Ye, Haifeng; Hamri, Ghislaine Charpin-El; Fussenegger, Martin

    2014-08-01

    Synthetic biology has significantly advanced the design of mammalian trigger-inducible transgene-control devices that are able to programme complex cellular behaviour. Fruit-based benzoate derivatives licensed as food additives, such as flavours (e.g. vanillate) and preservatives (e.g. benzoate), are a particularly attractive class of trigger compounds for orthogonal mammalian transgene control devices because of their innocuousness, physiological compatibility and simple oral administration. Capitalizing on the genetic componentry of the soil bacterium Comamonas testosteroni, which has evolved to catabolize a variety of aromatic compounds, we have designed different mammalian gene expression systems that could be induced and repressed by the food additives benzoate and vanillate. When implanting designer cells engineered for gene switch-driven expression of the human placental secreted alkaline phosphatase (SEAP) into mice, blood SEAP levels of treated animals directly correlated with a benzoate-enriched drinking programme. Additionally, the benzoate-/vanillate-responsive device was compatible with other transgene control systems and could be assembled into higher-order control networks providing expression dynamics reminiscent of a lap-timing stopwatch. Designer gene switches using licensed food additives as trigger compounds to achieve antagonistic dual-input expression profiles and provide novel control topologies and regulation dynamics may advance future gene- and cell-based therapies. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  4. COMBUSTION ADDITIVES FOR POLLUTION CONTROL - A STATE-OF-THE-ART REVIEW

    EPA Science Inventory

    The report is a state-of-the-art review of the potential of combustion-type fuel additives in reducing air pollutant emissions from oil and coal firing. It contains two complementary parts: a review of the relation of combustion mechanisms to additive action in controlling emissi...

  5. Controlling a multi-degree of freedom upper limb prosthesis using foot controls: user experience.

    PubMed

    Resnik, Linda; Klinger, Shana Lieberman; Etter, Katherine; Fantini, Christopher

    2014-07-01

    The DEKA Arm, a pre-commercial upper limb prosthesis, funded by the DARPA Revolutionizing Prosthetics Program, offers increased degrees of freedom while requiring a large number of user control inputs to operate. To address this challenge, DEKA developed prototype foot controls. Although the concept of utilizing foot controls to operate an upper limb prosthesis has been discussed for decades, only small-sized studies have been performed and no commercial product exists. The purpose of this paper is to report amputee user perspectives on using three different iterations of foot controls to operate the DEKA Arm. Qualitative data was collected from 36 subjects as part of the Department of Veterans Affairs (VA) Study to Optimize the DEKA Arm through surveys, interviews, audio memos, and videotaped sessions. Three major, interrelated themes were identified using the constant comparative method: attitudes towards foot controls, psychomotor learning and physical experience of using foot controls. Feedback about foot controls was generally positive for all iterations. The final version of foot controls was viewed most favorably. Our findings indicate that foot controls are a viable control option that can enable control of a multifunction upper limb prosthesis (the DEKA Arm). Multifunction upper limb prostheses require many user control inputs to operate. Foot controls offer additional control input options for such advanced devices, yet have had minimal study. This study found that foot controls were a viable option for controlling multifunction upper limb prostheses. Most of the 36 subjects in this study were willing to adopt foot controls to control the multiple degrees of freedom of the DEKA Arm. With training and practice, all users were able to develop the psychomotor skills needed to successfully operate food controls. Some had initial difficulty, but acclimated over time.

  6. Gas Chromatographic Determination of Methyl Salicylate in Rubbing Alcohol: An Experiment Employing Standard Addition.

    ERIC Educational Resources Information Center

    Van Atta, Robert E.; Van Atta, R. Lewis

    1980-01-01

    Provides a gas chromatography experiment that exercises the quantitative technique of standard addition to the analysis for a minor component, methyl salicylate, in a commercial product, "wintergreen rubbing alcohol." (CS)

  7. A comprehensive quality control workflow for paired tumor-normal NGS experiments.

    PubMed

    Schroeder, Christopher M; Hilke, Franz J; Löffler, Markus W; Bitzer, Michael; Lenz, Florian; Sturm, Marc

    2017-06-01

    Quality control (QC) is an important part of all NGS data analysis stages. Many available tools calculate QC metrics from different analysis steps of single sample experiments (raw reads, mapped reads and variant lists). Multi-sample experiments, as sequencing of tumor-normal pairs, require additional QC metrics to ensure validity of results. These multi-sample QC metrics still lack standardization. We therefore suggest a new workflow for QC of DNA sequencing of tumor-normal pairs. With this workflow well-known single-sample QC metrics and additional metrics specific for tumor-normal pairs can be calculated. The segmentation into different tools offers a high flexibility and allows reuse for other purposes. All tools produce qcML, a generic XML format for QC of -omics experiments. qcML uses quality metrics defined in an ontology, which was adapted for NGS. All QC tools are implemented in C ++ and run both under Linux and Windows. Plotting requires python 2.7 and matplotlib. The software is available under the 'GNU General Public License version 2' as part of the ngs-bits project: https://github.com/imgag/ngs-bits. christopher.schroeder@med.uni-tuebingen.de. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

  8. Damping-tunable energy-harvesting vehicle damper with multiple controlled generators: Design, modeling and experiments

    NASA Astrophysics Data System (ADS)

    Xie, Longhan; Li, Jiehong; Li, Xiaodong; Huang, Ledeng; Cai, Siqi

    2018-01-01

    Hydraulic dampers are used to decrease the vibration of a vehicle, where vibration energy is dissipated as heat. In addition to resulting in energy waste, the damping coefficient in hydraulic dampers cannot be changed during operation. In this paper, an energy-harvesting vehicle damper was proposed to replace traditional hydraulic dampers. The goal is not only to recover kinetic energy from suspension vibration but also to change the damping coefficient during operation according to road conditions. The energy-harvesting damper consists of multiple generators that are independently controlled by switches. One of these generators connects to a tunable resistor for fine tuning the damping coefficient, while the other generators are connected to a control and rectifying circuit, each of which both regenerates electricity and provides a constant damping coefficient. A mathematical model was built to investigate the performance of the energy-harvesting damper. By controlling the number of switched-on generators and adjusting the value of the external tunable resistor, the damping can be fine tuned according to the requirement. In addition to the capability of damping tuning, the multiple controlled generators can output a significant amount of electricity. A prototype was built to test the energy-harvesting damper design. Experiments on an MTS testing system were conducted, with results that validated the theoretical analysis. Experiments show that changing the number of switched-on generators can obviously tune the damping coefficient of the damper and simultaneously produce considerable electricity.

  9. Controlling behavioral experiments with a new programming language (SORCA) for microcomputer systems.

    PubMed

    Brinkhus, H B; Klinkenborg, H; Estorf, R; Weber, R

    1983-01-01

    A new programming language SORCA has been defined and a compiler has been written for Z80-based microcomputer systems with CP/M operating system. The language was developed to control behavioral experiments by external stimuli and by time schedule in real-time. Eight binary hardware input lines are sampled cyclically by the computer and can be used to sense switches, level detectors and other binary information, while 8 binary hardware output lines, that are cyclically updated, can be used to control relays, lamps, generate tones or for other purposes. The typical reaction time (cycle time) of a SORCA-program is 500 microseconds to 1 ms. All functions can be programmed as often as necessary. Included are the basic logic functions, counters, timers, majority gates and other complex functions. Parameters can be given as constants or as a result of a step function or of a random process (with Gaussian or equal distribution). Several tasks can be performed simultaneously. In addition, results of an experiment (e.g., number of reactions or latencies) can be measured and printed out on request or automatically. The language is easy to learn and can also be used for many other control purposes.

  10. GEECS (Generalized Equipment and Experiment Control System)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    GONSALVES, ANTHONY; DESHMUKH, AALHAD

    2017-01-12

    GEECS (Generalized Equipment and Experiment Control System) monitors and controls equipment distributed across a network, performs experiments by scanning input variables, and collects and stores various types of data synchronously from devices. Examples of devices include cameras, motors and pressure gauges. GEEKS is based upon LabView graphical object oriented programming (GOOP), allowing for a modular and scalable framework. Data is published for subscription of an arbitrary number of variables over TCP. A secondary framework allows easy development of graphical user interfaces for a combined control of any available devices on the control system without the need of programming knowledge. Thismore » allows for rapid integration of GEECS into a wide variety of systems. A database interface provides for devise and process configuration while allowing the user to save large quantities of data to local or network drives.« less

  11. Vibration Control of Deployable Astromast Boom: Preliminary Experiments

    NASA Technical Reports Server (NTRS)

    Swaminadham, M.; Hamilton, David A.

    1994-01-01

    This paper deals with the dynamic characterization of a flexible aerospace solar boom. The modeling issues and sine dwell vibration testing to determine natural frequencies and mode shapes of a continuous-longer on deployable ASTROMAST lattice boom are discussed. The details of the proof-of-concept piezoelectric active vibration experiments on a simple cantilever beam to control its vibrations are presented. The control parameters like voltage to the controller crystal and its location are investigated, to determine the effectiveness of control element to suppress selected resonant vibrations of the test specimen. Details of this experiment and plans for its future adaptation to the prototype structure are also discussed.

  12. Decentralized control experiments on NASA's flexible grid

    NASA Technical Reports Server (NTRS)

    Ozguner, U.; Yurkowich, S.; Martin, J., III; Al-Abbass, F.

    1986-01-01

    Methods arising from the area of decentralized control are emerging for analysis and control synthesis for large flexible structures. In this paper the control strategy involves a decentralized model reference adaptive approach using a variable structure control. Local models are formulated based on desired damping and response time in a model-following scheme for various modal configurations. Variable structure controllers are then designed employing co-located angular rate and position feedback. In this scheme local control forces the system to move on a local sliding mode in some local error space. An important feature of this approach is that the local subsystem is made insensitive to dynamical interactions with other subsystems once the sliding surface is reached. Experiments based on the above have been performed for NASA's flexible grid experimental apparatus. The grid is designed to admit appreciable low-frequency structural dynamics, and allows for implementation of distributed computing components, inertial sensors, and actuation devices. A finite-element analysis of the grid provides the model for control system design and simulation; results of several simulations are reported on here, and a discussion of application experiments on the apparatus is presented.

  13. Progress on control experiments of flexible structures

    NASA Technical Reports Server (NTRS)

    Juang, Jer-Nan

    1990-01-01

    Progress at the NASA Langley Research Center in the area of control experiments for flexible structures is described. First the author presents the experimental results for a linear model which represents slewing maneuvers of a generic space station solar panel carried out to evaluate experimentally some control technologies. Then the status of the rotational/translational maneuvering experiment of a flexible steel panel carried by a translation cart is presented. Finally, experimental results of the NASA minimast testbed using velocity command stepper motors as reaction mass reactors are shown. All the test configurations are briefly described, including actuator and sensor, test setup, and test software. The status of some research activities oriented primarily to the experimental methods for control of flexible structures is presented.

  14. A controlled experiment to evaluate the impact of summer research experiences on attitudes towards science in high school aged students

    NASA Astrophysics Data System (ADS)

    White, M. A.; Tcherednichenko, I.; Hamar, M.; Taylor, M. J.; Litizzette, L.

    2006-12-01

    United States funding agencies increasingly are supporting activities designed to increase the enrollment of United States high school students in science, math, or engineering careers. However, in many cases, the likely outcomes of educational activities are unknown. A common approach within the physical and natural sciences is to provide high school aged students with a summer research experience, with the expectation that such experiences will increase student interest in science, possibly as a career choice. With funding support from the National Aeronautics and Space Administration New Investigator Grant program, we conducted a controlled experiment to test this assumption. In collaboration with Mountain Crest High School in Logan, UT, we recruited 40 students currently enrolled in science courses, assessed attitudes towards science (with informed consent), and randomly assigned 20 students to a control group and 20 students to an experimental group. Students in the experimental group were paired with faculty and graduate students in a wide range of field and laboratory research groups in natural resources and biology. Students were employed in at least two different research groups for an average of 30-40 hours per week for eight weeks in the summer of 2006. Following the completion of the summer work experience, we again assessed attitudes towards science in both groups and gathered additional information from the experimental group on satisfaction with the work experience and reasons for participating. Results are presented and discussed.

  15. Experience with ActiveX control for simple channel access

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Timossi, C.; Nishimura, H.; McDonald, J.

    2003-05-15

    Accelerator control system applications at Berkeley Lab's Advanced Light Source (ALS) are typically deployed on operator consoles running Microsoft Windows 2000 and utilize EPICS[2]channel access for data access. In an effort to accommodate the wide variety of Windows based development tools and developers with little experience in network programming, ActiveX controls have been deployed on the operator stations. Use of ActiveX controls for use in the accelerator control environment has been presented previously[1]. Here we report on some of our experiences with the use and development of these controls.

  16. Chemical and biological consequences of using carbon dioxide versus acid additions in ocean acidification experiments

    USGS Publications Warehouse

    Yates, Kimberly K.; DuFore, Christopher M.; Robbins, Lisa L.

    2013-01-01

    Use of different approaches for manipulating seawater chemistry during ocean acidification experiments has confounded comparison of results from various experimental studies. Some of these discrepancies have been attributed to whether addition of acid (such as hydrochloric acid, HCl) or carbon dioxide (CO2) gas has been used to adjust carbonate system parameters. Experimental simulations of carbonate system parameter scenarios for the years 1766, 2007, and 2100 were performed using the carbonate speciation program CO2SYS to demonstrate the variation in seawater chemistry that can result from use of these approaches. Results showed that carbonate system parameters were 3 percent and 8 percent lower than target values in closed-system acid additions, and 1 percent and 5 percent higher in closed-system CO2 additions for the 2007 and 2100 simulations, respectively. Open-system simulations showed that carbonate system parameters can deviate by up to 52 percent to 70 percent from target values in both acid addition and CO2 addition experiments. Results from simulations for the year 2100 were applied to empirically derived equations that relate biogenic calcification to carbonate system parameters for calcifying marine organisms including coccolithophores, corals, and foraminifera. Calculated calcification rates for coccolithophores, corals, and foraminifera differed from rates at target conditions by 0.5 percent to 2.5 percent in closed-system CO2 gas additions, from 0.8 percent to 15 percent in the closed-system acid additions, from 4.8 percent to 94 percent in open-system acid additions, and from 7 percent to 142 percent in open-system CO2 additions.

  17. Control-based continuation: Bifurcation and stability analysis for physical experiments

    NASA Astrophysics Data System (ADS)

    Barton, David A. W.

    2017-02-01

    Control-based continuation is technique for tracking the solutions and bifurcations of nonlinear experiments. The idea is to apply the method of numerical continuation to a feedback-controlled physical experiment such that the control becomes non-invasive. Since in an experiment it is not (generally) possible to set the state of the system directly, the control target becomes a proxy for the state. Control-based continuation enables the systematic investigation of the bifurcation structure of a physical system, much like if it was numerical model. However, stability information (and hence bifurcation detection and classification) is not readily available due to the presence of stabilising feedback control. This paper uses a periodic auto-regressive model with exogenous inputs (ARX) to approximate the time-varying linearisation of the experiment around a particular periodic orbit, thus providing the missing stability information. This method is demonstrated using a physical nonlinear tuned mass damper.

  18. Description of the Spacecraft Control Laboratory Experiment (SCOLE) facility

    NASA Technical Reports Server (NTRS)

    Williams, Jeffrey P.; Rallo, Rosemary A.

    1987-01-01

    A laboratory facility for the study of control laws for large flexible spacecraft is described. The facility fulfills the requirements of the Spacecraft Control Laboratory Experiment (SCOLE) design challenge for a laboratory experiment, which will allow slew maneuvers and pointing operations. The structural apparatus is described in detail sufficient for modelling purposes. The sensor and actuator types and characteristics are described so that identification and control algorithms may be designed. The control implementation computer and real-time subroutines are also described.

  19. Description of the Spacecraft Control Laboratory Experiment (SCOLE) facility

    NASA Technical Reports Server (NTRS)

    Williams, Jeffrey P.; Rallo, Rosemary A.

    1987-01-01

    A laboratory facility for the study of control laws for large flexible spacecraft is described. The facility fulfills the requirements of the Spacecraft Control Laboratory Experiment (SCOLE) design challenge for laboratory experiments, which will allow slew maneuvers and pointing operations. The structural apparatus is described in detail sufficient for modelling purposes. The sensor and actuator types and characteristics are described so that identification and control algorithms may be designed. The control implementation computer and real-time subroutines are also described.

  20. Automated multi-slice extracellular and patch-clamp experiments using the WinLTP data acquisition system with automated perfusion control

    PubMed Central

    Anderson, William W.; Fitzjohn, Stephen M.; Collingridge, Graham L.

    2012-01-01

    WinLTP is a data acquisition program for studying long-term potentiation (LTP) and other aspects of synaptic function. Earlier versions of WinLTP (J. Neurosci. Methods, 162:346–356, 2007) provided automated electrical stimulation and data acquisition capable of running nearly an entire synaptic plasticity experiment, with the primary exception that perfusion solutions had to be changed manually. This automated stimulation and acquisition was done by using ‘Sweep’, ‘Loop’ and ‘Delay’ events to build scripts using the ‘Protocol Builder’. However, this did not allow automatic changing of many solutions while running multiple slice experiments, or solution changing when this had to be performed rapidly and with accurate timing during patch-clamp experiments. We report here the addition of automated perfusion control to WinLTP. First, perfusion change between sweeps is enabled by adding the ‘Perfuse’ event to Protocol Builder scripting and is used in slice experiments. Second, fast perfusion changes during as well as between sweeps is enabled by using the Perfuse event in the protocol scripts to control changes between sweeps, and also by changing digital or analog output during a sweep and is used for single cell single-line perfusion patch-clamp experiments. The addition of stepper control of tube placement allows dual- or triple-line perfusion patch-clamp experiments for up to 48 solutions. The ability to automate perfusion changes and fully integrate them with the already automated stimulation and data acquisition goes a long way toward complete automation of multi-slice extracellularly recorded and single cell patch-clamp experiments. PMID:22524994

  1. ASSISTments Dataset from Multiple Randomized Controlled Experiments

    ERIC Educational Resources Information Center

    Selent, Douglas; Patikorn, Thanaporn; Heffernan, Neil

    2016-01-01

    In this paper, we present a dataset consisting of data generated from 22 previously and currently running randomized controlled experiments inside the ASSISTments online learning platform. This dataset provides data mining opportunities for researchers to analyze ASSISTments data in a convenient format across multiple experiments at the same time.…

  2. Compliance and control characteristics of an additive manufactured-flexure stage

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, ChaBum; Tarbutton, Joshua A.

    2015-04-15

    This paper presents a compliance and positioning control characteristics of additive manufactured-nanopositioning system consisted of the flexure mechanism and voice coil motor (VCM). The double compound notch type flexure stage was designed to utilize the elastic deformation of two symmetrical four-bar mechanisms to provide a millimeter-level working range. Additive manufacturing (AM) process, stereolithography, was used to fabricate the flexure stage. The AM stage was inspected by using 3D X-ray computerized tomography scanner: air-voids and shape irregularity. The compliance, open-loop resonance peak, and damping ratio of the AM stage were measured 0.317 mm/N, 80 Hz, and 0.19, respectively. The AM stagemore » was proportional-integral-derivative positioning feedback-controlled and the capacitive type sensor was used to measure the displacement. As a result, the AM flexure mechanism was successfully 25 nm positioning controlled within 500 μm range. The resonance peak was found approximately at 280 Hz in closed-loop. This research showed that the AM flexure mechanism and the VCM can provide millimeter range with high precision and can be a good alternative to an expensive metal-based flexure mechanism and piezoelectric transducer.« less

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

    ERIC Educational Resources Information Center

    Henry, Jim; Schaedel, Herbert M.

    2005-01-01

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

  4. Automated Steering Control Design by Visual Feedback Approach —System Identification and Control Experiments with a Radio-Controlled Car—

    NASA Astrophysics Data System (ADS)

    Fujiwara, Yukihiro; Yoshii, Masakazu; Arai, Yasuhito; Adachi, Shuichi

    Advanced safety vehicle(ASV)assists drivers’ manipulation to avoid trafic accidents. A variety of researches on automatic driving systems are necessary as an element of ASV. Among them, we focus on visual feedback approach in which the automatic driving system is realized by recognizing road trajectory using image information. The purpose of this paper is to examine the validity of this approach by experiments using a radio-controlled car. First, a practical image processing algorithm to recognize white lines on the road is proposed. Second, a model of the radio-controlled car is built by system identication experiments. Third, an automatic steering control system is designed based on H∞ control theory. Finally, the effectiveness of the designed control system is examined via traveling experiments.

  5. GMPLS-based control plane for optical networks: early implementation experience

    NASA Astrophysics Data System (ADS)

    Liu, Hang; Pendarakis, Dimitrios; Komaee, Nooshin; Saha, Debanjan

    2002-07-01

    Generalized Multi-Protocol Label Switching (GMPLS) extends MPLS signaling and Internet routing protocols to provide a scalable, interoperable, distributed control plane, which is applicable to multiple network technologies such as optical cross connects (OXCs), photonic switches, IP routers, ATM switches, SONET and DWDM systems. It is intended to facilitate automatic service provisioning and dynamic neighbor and topology discovery across multi-vendor intelligent transport networks, as well as their clients. Efforts to standardize such a distributed common control plane have reached various stages in several bodies such as the IETF, ITU and OIF. This paper describes the design considerations and architecture of a GMPLS-based control plane that we have prototyped for core optical networks. Functional components of GMPLS signaling and routing are integrated in this architecture with an application layer controller module. Various requirements including bandwidth, network protection and survivability, traffic engineering, optimal utilization of network resources, and etc. are taken into consideration during path computation and provisioning. Initial experiments with our prototype demonstrate the feasibility and main benefits of GMPLS as a distributed control plane for core optical networks. In addition to such feasibility results, actual adoption and deployment of GMPLS as a common control plane for intelligent transport networks will depend on the successful completion of relevant standardization activities, extensive interoperability testing as well as the strengthening of appropriate business drivers.

  6. Low-Cost Undergraduate Control Systems Experiments Using Microcontroller-Based Control of a DC Motor

    ERIC Educational Resources Information Center

    Gunasekaran, M.; Potluri, R.

    2012-01-01

    This paper presents low-cost experiments for a control systems laboratory module that is worth one and a third credits. The experiments are organized around the microcontroller-based control of a permanent magnet dc motor. The experimental setups were built in-house. Except for the operating system, the software used is primarily freeware or free…

  7. Stratospheric controlled perturbation experiment: a small-scale experiment to improve understanding of the risks of solar geoengineering.

    PubMed

    Dykema, John A; Keith, David W; Anderson, James G; Weisenstein, Debra

    2014-12-28

    Although solar radiation management (SRM) through stratospheric aerosol methods has the potential to mitigate impacts of climate change, our current knowledge of stratospheric processes suggests that these methods may entail significant risks. In addition to the risks associated with current knowledge, the possibility of 'unknown unknowns' exists that could significantly alter the risk assessment relative to our current understanding. While laboratory experimentation can improve the current state of knowledge and atmospheric models can assess large-scale climate response, they cannot capture possible unknown chemistry or represent the full range of interactive atmospheric chemical physics. Small-scale, in situ experimentation under well-regulated circumstances can begin to remove some of these uncertainties. This experiment-provisionally titled the stratospheric controlled perturbation experiment-is under development and will only proceed with transparent and predominantly governmental funding and independent risk assessment. We describe the scientific and technical foundation for performing, under external oversight, small-scale experiments to quantify the risks posed by SRM to activation of halogen species and subsequent erosion of stratospheric ozone. The paper's scope includes selection of the measurement platform, relevant aspects of stratospheric meteorology, operational considerations and instrument design and engineering.

  8. Jet mixing in low gravity - Results of the Tank Pressure Control Experiment

    NASA Technical Reports Server (NTRS)

    Bentz, M. D.; Meserole, J. S.; Knoll, R. H.

    1992-01-01

    The Tank Pressure Control Experiment (TPCE) is discussed with attention given to the results for controlling storage-tank pressures by forced-convective mixing in microgravitational environments. The fluid dynamics of cryogenic fluids in space is simulated with freon-113 during axial-jet-induced mixing. The experimental flow-pattern data are found to confirm previous data as well as existing mixing correlations. Thermal nonuniformities and tank pressure can be reduced by employing low-energy mixing jets which are useful for enhancing heat/mass transfer between phases. It is found that space cryogenic systems based on the principle of active mixing can be more reliable and predictable than other methods, and continuous or periodic mixing can be accomplished with only minor energy addition to the fluid.

  9. Reactor transient control in support of PFR/TREAT TUCOP experiments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Burrows, D.R.; Larsen, G.R.; Harrison, L.J.

    1984-01-01

    Unique energy deposition and experiment control requirements posed bythe PFR/TREAT series of transient undercooling/overpower (TUCOP) experiments resulted in equally unique TREAT reactor operations. New reactor control computer algorithms were written and used with the TREAT reactor control computer system to perform such functions as early power burst generation (based on test train flow conditions), burst generation produced by a step insertion of reactivity following a controlled power ramp, and shutdown (SCRAM) initiators based on both test train conditions and energy deposition. Specialized hardware was constructed to simulate test train inputs to the control computer system so that computer algorithms couldmore » be tested in real time without irradiating the experiment.« less

  10. Attitude control fault protection - The Voyager experience

    NASA Technical Reports Server (NTRS)

    Litty, E. C.

    1980-01-01

    The length of the Voyager mission and the communication delay caused by the distances involved made fault protection a necessary part of the Voyager Attitude and Articulation Control Subsystem (AACS) design. An overview of the Voyager attitude control fault protection is given and flight experiences relating to fault protection are provided.

  11. Hospital cost control in Norway: a decade's experience with prospective payment.

    PubMed Central

    Crane, T S

    1985-01-01

    Under Norway's prospective payment system, which was in existence from 1972 to 1980, hospital costs increased 15.8 percent annually, compared with 15.3 percent in the United States. In 1980 the Norwegian national government started paying for all institutional services according to a population-based, morbidity-adjusted formula. Norway's prospective payment system provides important insights into problems of controlling hospital costs despite significant differences, including ownership of medical facilities and payment and spending as a percent of GNP. Yet striking similarities exist. Annual real growth in health expenditures from 1972 to 1980 in Norway was 2.2 percent, compared with 2.4 percent in the United States. In both countries, public demands for cost control were accompanied by demands for more services. And problems of geographic dispersion of new technology and distribution of resources were similar. Norway's experience in the 1970s demonstrates that prospective payment is no panacea. The annual budget process created disincentives to hospitals to control costs. But Norway's changes in 1980 to a population-based methodology suggest a useful approach to achieve a more equitable distribution of resources. This method of payment provides incentives to control variations in both admissions and cost per case. In contrast, the Medicare approach based on Diagnostic Related Groups (DRGs) is limited, and it does not affect variations in admissions and capital costs. Population-based methodologies can be used in adjusting DRG rates to control both problems. In addition, the DRG system only applies to Medicare payments; the Norwegian experience demonstrates that this system may result in significant shifting of costs onto other payors. PMID:3927385

  12. The Biopsychology-Toolbox: a free, open-source Matlab-toolbox for the control of behavioral experiments.

    PubMed

    Rose, Jonas; Otto, Tobias; Dittrich, Lars

    2008-10-30

    The Biopsychology-Toolbox is a free, open-source Matlab-toolbox for the control of behavioral experiments. The major aim of the project was to provide a set of basic tools that allow programming novices to control basic hardware used for behavioral experimentation without limiting the power and flexibility of the underlying programming language. The modular design of the toolbox allows portation of parts as well as entire paradigms between different types of hardware. In addition to the toolbox, this project offers a platform for the exchange of functions, hardware solutions and complete behavioral paradigms.

  13. Reproducible and controllable induction voltage adder for scaled beam experiments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sakai, Yasuo; Nakajima, Mitsuo; Horioka, Kazuhiko

    2016-08-15

    A reproducible and controllable induction adder was developed using solid-state switching devices and Finemet cores for scaled beam compression experiments. A gate controlled MOSFET circuit was developed for the controllable voltage driver. The MOSFET circuit drove the induction adder at low magnetization levels of the cores which enabled us to form reproducible modulation voltages with jitter less than 0.3 ns. Preliminary beam compression experiments indicated that the induction adder can improve the reproducibility of modulation voltages and advance the beam physics experiments.

  14. The morbidity experience of air traffic control personnel, 1967-1977.

    DOT National Transportation Integrated Search

    1978-04-01

    The morbidity experience of 28,086 air traffic controllers has been examined from 1967-77 with particular emphasis given the potential effects of job demands on ATC Health. The morbidity experience of air traffic controllers does not appear excessive...

  15. Emission control devices, fuel additive, and fuel composition changes.

    PubMed Central

    Piver, W T

    1977-01-01

    Emission control devices are installed to meet the exhaust standards of the Clean Air Act for carbon monoxide and hydrocarbons, and it is necessary to know, from a public health point of view, how exhaust emissions may be affected by changes in fuel additives and fuel composition. Since these topics are concerned with developing technologies, the available literature on exhaust emission characteristics and the limited information on health effects, is reviewed. PMID:71235

  16. Controls on Lava Flow Morphology and Propagation: Using Laboratory Analogue Experiments

    NASA Astrophysics Data System (ADS)

    Peters, S.; Clarke, A. B.

    2017-12-01

    The morphology of lava flows is controlled by eruption rate, composition, cooling rate, and topography [Fink and Griffiths, 1990; Gregg and Fink, 2000, 2006]. Lava flows are used to understand how volcanoes, volcanic fields, and igneous provinces formed and evolved [Gregg and Fink., 1996; Sheth, 2006]. This is particularly important for other planets where compositional data is limited and historical context is nonexistent. Numerical modeling of lava flows remains challenging, but has been aided by laboratory analog experiments [Gregg and Keszrthelyi, 2004; Soule and Cashman, 2004]. Experiments using polyethylene glycol (PEG) 600 wax have been performed to understand lava flow emplacement [Fink and Griffiths, 1990, 1992; Gregg and Fink, 2000]. These experiments established psi (hereafter denoted by Ψ), a dimensionless parameter that relates crust formation and advection timescales of a viscous gravity current. Four primary flow morphologies corresponding to discreet Ψ ranges were observed. Gregg and Fink [2000] also investigated flows on slopes and found that steeper slopes increase the effective effusion rate producing predicted morphologies at lower Ψ values. Additional work is needed to constrain the Ψ parameter space, evaluate the predictive capability of Ψ, and determine if the preserved flow morphology can be used to indicate the initial flow conditions. We performed 514 experiments to address the following controls on lava flow morphology: slope (n = 282), unsteadiness/pulsations (n = 58), slope & unsteadiness/pulsations (n = 174), distal processes, and emplacement vs. post-emplacement morphologies. Our slope experiments reveal a similar trend to Gregg and Fink [2000] with the caveat that very high and very low local & source eruption rates can reduce the apparent predictive capability of Ψ. Predicted Ψ morphologies were often produced halfway through the eruption. Our pulse experiments are expected to produce morphologies unique to each eruption rate

  17. Diffraction experiments with infrared remote controls

    NASA Astrophysics Data System (ADS)

    Kuhn, Jochen; Vogt, Patrik

    2012-02-01

    In this paper we describe an experiment in which radiation emitted by an infrared remote control is passed through a diffraction grating. An image of the diffraction pattern is captured using a cell phone camera and then used to determine the wavelength of the radiation.

  18. Distributed control network for optogenetic experiments

    NASA Astrophysics Data System (ADS)

    Kasprowicz, G.; Juszczyk, B.; Mankiewicz, L.

    2014-11-01

    Nowadays optogenetic experiments are constructed to examine social behavioural relations in groups of animals. A novel concept of implantable device with distributed control network and advanced positioning capabilities is proposed. It is based on wireless energy transfer technology, micro-power radio interface and advanced signal processing.

  19. Nitrate removal in stream ecosystems measured by 15N addition experiments: Total uptake

    USGS Publications Warehouse

    Hall, R.O.; Tank, J.L.; Sobota, D.J.; Mulholland, P.J.; O'Brien, J. M.; Dodds, W.K.; Webster, J.R.; Valett, H.M.; Poole, G.C.; Peterson, B.J.; Meyer, J.L.; McDowell, W.H.; Johnson, S.L.; Hamilton, S.K.; Grimm, N. B.; Gregory, S.V.; Dahm, Clifford N.; Cooper, L.W.; Ashkenas, L.R.; Thomas, S.M.; Sheibley, R.W.; Potter, J.D.; Niederlehner, B.R.; Johnson, L.T.; Helton, A.M.; Crenshaw, C.M.; Burgin, A.J.; Bernot, M.J.; Beaulieu, J.J.; Arangob, C.P.

    2009-01-01

    We measured uptake length of 15NO-3 in 72 streams in eight regions across the United States and Puerto Rico to develop quantitative predictive models on controls of NO-3 uptake length. As part of the Lotic Intersite Nitrogen eXperiment II project, we chose nine streams in each region corresponding to natural (reference), suburban-urban, and agricultural land uses. Study streams spanned a range of human land use to maximize variation in NO-3 concentration, geomorphology, and metabolism. We tested a causal model predicting controls on NO-3 uptake length using structural equation modeling. The model included concomitant measurements of ecosystem metabolism, hydraulic parameters, and nitrogen concentration. We compared this structural equation model to multiple regression models which included additional biotic, catchment, and riparian variables. The structural equation model explained 79% of the variation in log uptake length (S Wtot). Uptake length increased with specific discharge (Q/w) and increasing NO-3 concentrations, showing a loss in removal efficiency in streams with high NO-3 concentration. Uptake lengths shortened with increasing gross primary production, suggesting autotrophic assimilation dominated NO-3 removal. The fraction of catchment area as agriculture and suburban-urban land use weakly predicted NO-3 uptake in bivariate regression, and did improve prediction in a set of multiple regression models. Adding land use to the structural equation model showed that land use indirectly affected NO-3 uptake lengths via directly increasing both gross primary production and NO-3 concentration. Gross primary production shortened SWtot, while increasing NO-3 lengthened SWtot resulting in no net effect of land use on NO- 3 removal. ?? 2009.

  20. Control of abusive water addition to Octopus vulgaris with non-destructive methods.

    PubMed

    Mendes, Rogério; Schimmer, Ove; Vieira, Helena; Pereira, João; Teixeira, Bárbara

    2018-01-01

    Abusive water addition to octopus has evidenced the need for quick non-destructive methods for product qualification in the industry and control of fresh commercial products in markets. Electric conductivity (EC)/pH and dielectric property measurements were selected to detect water uptake in octopus. A significant EC decrease was determined after soaking octopus in freshwater for 4 h. EC reflected the water uptake of octopus and the correspondent concentration decrease of available ions in the interstitial fluid. Significant correlations were determined between octopus water uptake, EC (R = -0.940) and moisture/protein (M/P) ratio (R = 0.923) changes. Seasonal and spatial variation in proximate composition did not introduce any uncertainty in EC discrimination of freshwater tampering. Immersion in 5 g L -1 sodium tripolyphosphate (STPP) increased EC to a value similar to control octopus. EC false negatives resulting from the use of additives (STPP and citric acid) were eliminated with the additional determination of pH. Octopus soaked in freshwater, STPP and citric acid can also be clearly discriminated from untreated samples (control) and also from frozen (thawed) ones using the dielectric properties. No significant differences in the dielectric property scores were found between octopus sizes or geographical locations. Simultaneous EC/pH or dielectric property measurements can be used in a handheld device for non-destructive water addition detection in octopus. M/P ratio can be used as a reference destructive method. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  1. Apollo experience report: Lunar module environmental control subsystem

    NASA Technical Reports Server (NTRS)

    Gillen, R. J.; Brady, J. C.; Collier, F.

    1972-01-01

    A functional description of the environmental control subsystem is presented. Development, tests, checkout, and flight experiences of the subsystem are discussed; and the design fabrication, and operational difficulties associated with the various components and subassemblies are recorded. Detailed information is related concerning design changes made to, and problems encountered with, the various elements of the subsystem, such as the thermal control water sublimator, the carbon dioxide sensing and control units, and the water section. The problems associated with water sterilization, water/glycol formulation, and materials compatibility are discussed. The corrective actions taken are described with the expection that this information may be of value for future subsystems. Although the main experiences described are problem oriented, the subsystem has generally performed satisfactorily in flight.

  2. Social control, social learning, and cheating: Evidence from lab and online experiments on dishonesty.

    PubMed

    Kroher, Martina; Wolbring, Tobias

    2015-09-01

    Varying the conditions of the decision-making environment we offered participants the opportunity to increase their payoff by undetectable lies. In addition to a baseline treatment, in which subjects rolled a die in private and showed a high extent of dishonest behavior, we increased the degree of social control by a novel treatment in which subjects played in randomly assigned pairs of two. The presence of others proved to substantially, but only temporarily reduce dishonest behavior. Furthermore, one treatment group received feedback on unethical behavior of participants in a similar experiment. Knowing that others betrayed in the experiment facilitated social learning and led to a higher prevalence of cheating. Finally, increasing the degree of anonymity by re-running the experiment online increased the extent of norm transgressions slightly. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Additive Routes to Action Learning: Layering Experience Shapes Engagement of the Action Observation Network.

    PubMed

    Kirsch, Louise P; Cross, Emily S

    2015-12-01

    The way in which we perceive others in action is biased by one's prior experience with an observed action. For example, we can have auditory, visual, or motor experience with actions we observe others perform. How action experience via 1, 2, or all 3 of these modalities shapes action perception remains unclear. Here, we combine pre- and post-training functional magnetic resonance imaging measures with a dance training manipulation to address how building experience (from auditory to audiovisual to audiovisual plus motor) with a complex action shapes subsequent action perception. Results indicate that layering experience across these 3 modalities activates a number of sensorimotor cortical regions associated with the action observation network (AON) in such a way that the more modalities through which one experiences an action, the greater the response is within these AON regions during action perception. Moreover, a correlation between left premotor activity and participants' scores for reproducing an action suggests that the better an observer can perform an observed action, the stronger the neural response is. The findings suggest that the number of modalities through which an observer experiences an action impacts AON activity additively, and that premotor cortical activity might serve as an index of embodiment during action observation. © The Author 2015. Published by Oxford University Press.

  4. Crystallization Experiments of the Martian Meteorite QUE94201: Additional Constraints on Its Formation Condition

    NASA Technical Reports Server (NTRS)

    Koizumi, E.; McKay, G.; Mikouchi, T.; Le, L.; Schwandt, C.; Monkawa, A.; Miyamoto, M.

    2002-01-01

    We focused on the Al/Ti ratio in synthetic pyroxenes as a marker for the onset of plagioclase crystallization and discuss the effects of oxygen fugacity on the Kd(Fe/Mg)ol/gl in our experiments using the same composition of QUE94201. Additional information is contained in the original extended abstract.

  5. Citrus Quality Control: An NMR/MRI Problem-Based Experiment

    ERIC Educational Resources Information Center

    Erhart, Sarah E.; McCarrick, Robert M.; Lorigan, Gary A.; Yezierski, Ellen J.

    2016-01-01

    An experiment seated in an industrial context can provide an engaging framework and unique learning opportunity for an upper-division physical chemistry laboratory. An experiment that teaches NMR/MRI through a problem-based quality control of citrus products was developed. In this experiment, using a problem-based learning (PBL) approach, students…

  6. Low-cost Active Structural Control Space Experiment (LASC)

    NASA Technical Reports Server (NTRS)

    Robinett, Rush; Bukley, Angelia P.

    1992-01-01

    The DOE Lab Director's Conference identified the need for the DOE National Laboratories to actively and aggressively pursue ways to apply DOE technology to problems of national need. Space structures are key elements of DOD and NASA space systems and a space technology area in which DOE can have a significant impact. LASC is a joint agency space technology experiment (DOD Phillips, NASA Marshall, and DOE Sandia). The topics are presented in viewgraph form and include the following: phase 4 investigator testbed; control of large flexible structures in orbit; INFLEX; Controls, Astrophysics; and structures experiments in space; SARSAT; and LASC mission objectives.

  7. A high voltage pulse generator based on silicon-controlled rectifier for field-reversed configuration experiment.

    PubMed

    Lin, Munan; Liu, Ming; Zhu, Guanghui; Wang, Yanpeng; Shi, Peiyun; Sun, Xuan

    2017-08-01

    A high voltage pulse generator based on a silicon-controlled rectifier has been designed and implemented for a field reversed configuration experiment. A critical damping circuit is used in the generator to produce the desired pulse waveform. Depending on the load, the rise time of the output trigger signal can be less than 1 μs, and the peak amplitudes of trigger voltage and current are up to 8 kV and 85 A in a single output. The output voltage can be easily adjusted by changing the voltage on a capacitor of the generator. In addition, the generator integrates an electrically floating heater circuit so it is capable of triggering either pseudosparks (TDI-type hydrogen thyratron) or ignitrons. Details of the circuits and their implementation are described in the paper. The trigger generator has successfully controlled the discharging sequence of the pulsed power supply for a field reversed configuration experiment.

  8. A high voltage pulse generator based on silicon-controlled rectifier for field-reversed configuration experiment

    NASA Astrophysics Data System (ADS)

    Lin, Munan; Liu, Ming; Zhu, Guanghui; Wang, Yanpeng; Shi, Peiyun; Sun, Xuan

    2017-08-01

    A high voltage pulse generator based on a silicon-controlled rectifier has been designed and implemented for a field reversed configuration experiment. A critical damping circuit is used in the generator to produce the desired pulse waveform. Depending on the load, the rise time of the output trigger signal can be less than 1 μs, and the peak amplitudes of trigger voltage and current are up to 8 kV and 85 A in a single output. The output voltage can be easily adjusted by changing the voltage on a capacitor of the generator. In addition, the generator integrates an electrically floating heater circuit so it is capable of triggering either pseudosparks (TDI-type hydrogen thyratron) or ignitrons. Details of the circuits and their implementation are described in the paper. The trigger generator has successfully controlled the discharging sequence of the pulsed power supply for a field reversed configuration experiment.

  9. Voyager Saturn encounter attitude and articulation control experience

    NASA Technical Reports Server (NTRS)

    Carlisle, G.; Hill, M.

    1981-01-01

    The Voyager attitude and articulation control system is designed for a three-axis stabilized spacecraft; it uses a biasable sun sensor and a Canopus Star Tracker (CST) for celestial control, as well as a dry inertial reference unit, comprised of three dual-axis dry gryos, for inertial control. A series of complex maneuvers was required during the first of two Voyager spacecraft encounters with Saturn (November 13, 1980); these maneuvers involved rotating the spacecraft simultaneously about two or three axes while maintaining accurate pointing of the scan platform. Titan and Saturn earth occulation experiments and a ring scattering experiment are described. Target motion compensation and the effects of celestial sensor interference are also considered. Failure of the CST, which required an extensive reevaluation of the star reference and attitude control mode strategy, is discussed. Results analyzed thus far show that the system performed with high accuracy, gathering data deeper into Saturn's atmosphere than on any previous planetary encounter.

  10. A slewing control experiment for flexible structures

    NASA Technical Reports Server (NTRS)

    Juang, J.-N.; Horta, L. G.; Robertshaw, H. H.

    1985-01-01

    A hardware set-up has been developed to study slewing control for flexible structures including a steel beam and a solar panel. The linear optimal terminal control law is used to design active controllers which are implemented in an analog computer. The objective of this experiment is to demonstrate and verify the dynamics and optimal terminal control laws as applied to flexible structures for large angle maneuver. Actuation is provided by an electric motor while sensing is given by strain gages and angle potentiometer. Experimental measurements are compared with analytical predictions in terms of modal parameters of the system stability matrix and sufficient agreement is achieved to validate the theory.

  11. A mathematical problem and a Spacecraft Control Laboratory Experiment (SCOLE) used to evaluate control laws for flexible spacecraft. NASA/IEEE design challenge

    NASA Technical Reports Server (NTRS)

    Taylor, Lawrence W., Jr.; Balakrishnan, A. V.

    1988-01-01

    The problen of controlling large, flexible space systems has been evaluated using computer simulation. In several cases, ground experiments have also been used to validate system performance under more realistic conditions. There remains a need, however, to test additional control laws for flexible spacecraft and to directly compare competing design techniques. A program is discussed which has been initiated to make direct comparisons of control laws for, first, a mathematical problem, then and experimental test article being assembled under the cognizance of the Spacecraft Control Branch at the NASA Langley Research Center with the advice and counsel of the IEEE Subcommittee on Large Space Structures. The physical apparatus will consist of a softly supported dynamic model of an antenna attached to the Shuttle by a flexible beam. The control objective will include the task of directing the line-of-sight of the Shuttle antenna configuration toward a fixed target, under conditions of noisy data, control authority and random disturbances.

  12. Millikan's Oil-Drop Experiment as a Remotely Controlled Laboratory

    ERIC Educational Resources Information Center

    Eckert, Bodo; Grober, Sebastian; Vetter, Martin; Jodl, Hans-Jorg

    2012-01-01

    The Millikan oil-drop experiment, to determine the elementary electrical charge e and the quantization of charge Q = n [middle dot] e, is an essential experiment in physics teaching but it is hardly performed in class for several reasons. Therefore, we offer this experiment as a remotely controlled laboratory (RCL). We describe the interactivity…

  13. Can uptake length in strams be determined by nutrient addition experiments? Results from an interbiome comparison study

    Treesearch

    P. J Mulholland; J. L. Tanks; J. R. Webster; W. B. Bowden; W. K Dodds; S. V. Gregory; N. B Grimm; J. L. Meriam; J. L. Meyer; B. J. Peterson; H. M. Valett; W. M. Wollheim

    2002-01-01

    Nutrient uptake length is an important parnmeter tor quantifying nutrient cycling in streams. Although nutrient tracer additions are the preierred method for measuring uptake length under ambient nutrient concentrations, short-term nutrient addition experiments have more irequently been used to estimate uptake length in streams. Theoretical analysis of the relationship...

  14. Expectations and Experience: Dissociable Bases for Cognitive Control?

    ERIC Educational Resources Information Center

    Bugg, Julie M.; Diede, Nathaniel T.; Cohen-Shikora, Emily R.; Selmeczy, Diana

    2015-01-01

    Classic theories emphasized the role of expectations in the intentional control of attention and action. However, recent theorizing has implicated experience-dependent, online adjustments as the primary basis for cognitive control--adjustments that appear to be implicit (Blais, Harris, Guerrero, & Bunge, 2012). The purpose of the current study…

  15. Testing of the palatability of Thymus vulgaris L. and Origanum vulgare L. as flavouring feed additive for weaner pigs on the basis of a choice experiment.

    PubMed

    Jugl-Chizzola, Martina; Ungerhofer, Elisabeth; Gabler, Cornelia; Hagmüller, Werner; Chizzola, Remigius; Zitterl-Eglseer, Karin; Franz, Chlodwig

    2006-01-01

    The objective of the study at hand was to investigate within the framework of a pilot project the preference of weaner pigs for either an ad libitum standard feed with thyme or oregano herb as flavouring additive or an ad libitum standard feed without any herbal additive. Thyme or oregano herbs or a combination of both were offered in two different concentrations each (1% and 0.1%) as additive (experimental diets) in standard diet in comparison to the latter without herbal additive (control diet) free of choice. The dosage of the two herbs in terms of total essential oil(s) in the feeds used in the study was 0.02% or 0.002% (v/w), which was equivalent to 1% or 0.1% herbs in the mixture, respectively. A Latin square according to Williams (1949) was used with 6 groups in order to record possible differences in feed intake. All experimental diets aside from that mixed with 0.1% thyme herb were, in comparison to the control diet, significantly less ingested. Where the weanling was given the choice, it did not choose feed with any flavouring additive. Further studies aimed at assessing the use of herbs as aroma additive in the form of a choice experiment are recommended.

  16. Efficient Improvement of Silage Additives by Using Genetic Algorithms

    PubMed Central

    Davies, Zoe S.; Gilbert, Richard J.; Merry, Roger J.; Kell, Douglas B.; Theodorou, Michael K.; Griffith, Gareth W.

    2000-01-01

    The enormous variety of substances which may be added to forage in order to manipulate and improve the ensilage process presents an empirical, combinatorial optimization problem of great complexity. To investigate the utility of genetic algorithms for designing effective silage additive combinations, a series of small-scale proof of principle silage experiments were performed with fresh ryegrass. Having established that significant biochemical changes occur over an ensilage period as short as 2 days, we performed a series of experiments in which we used 50 silage additive combinations (prepared by using eight bacterial and other additives, each of which was added at six different levels, including zero [i.e., no additive]). The decrease in pH, the increase in lactate concentration, and the free amino acid concentration were measured after 2 days and used to calculate a “fitness” value that indicated the quality of the silage (compared to a control silage made without additives). This analysis also included a “cost” element to account for different total additive levels. In the initial experiment additive levels were selected randomly, but subsequently a genetic algorithm program was used to suggest new additive combinations based on the fitness values determined in the preceding experiments. The result was very efficient selection for silages in which large decreases in pH and high levels of lactate occurred along with low levels of free amino acids. During the series of five experiments, each of which comprised 50 treatments, there was a steady increase in the amount of lactate that accumulated; the best treatment combination was that used in the last experiment, which produced 4.6 times more lactate than the untreated silage. The additive combinations that were found to yield the highest fitness values in the final (fifth) experiment were assessed to determine a range of biochemical and microbiological quality parameters during full-term silage

  17. Electric utility use of fireside additives. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Locklin, D.W.; Krause, H.H.; Anson, D.

    1980-01-01

    Fireside additives have been used or proposed for use in fossil-fired utility boilers to combat a number of problems related to boiler performance and reliability. These problems include corrosion, fouling, superheat control, and acidic emissions. Fuel additives and other fireside additives have been used mainly with oil firing; however, there is growing experience with additives in coal-firing, especially for flyash conditioning to improve the performance of electrostatic precipitators. In decisions regarding the selection and use of additives, utilities have had to rely extensively on empiricism, due partly to an incomplete understanding of processes involved and partly to the limited amountmore » of quantitative data. The study reported here was sponsored by the Electric Power Research Institute to assemble and analyze pertinent operating experience and to recommend guidelines for utility decisions on the use of additives. The combined results of the state-of-the-art review of technical literature and a special survey of utility experience are reported. A total of 38 utilities participated in the survey, providing information on trials conducted on 104 units in 93 different plants. Altogether, 445 separate trials were reported, each representing a unit/additive/fuel combination. Additives used in these trials included 90 different additive formulations, both pure compounds and proprietary products. These formulations were categorized into 37 generic classes according to their chemical constituents, and the results of the survey are presented by these generic classes. The findings are organized according to the operating problems for which fireside additives are used. Guidelines are presented for utility use in additive selection and in planning additive trials.« less

  18. Automating quantum experiment control

    NASA Astrophysics Data System (ADS)

    Stevens, Kelly E.; Amini, Jason M.; Doret, S. Charles; Mohler, Greg; Volin, Curtis; Harter, Alexa W.

    2017-03-01

    The field of quantum information processing is rapidly advancing. As the control of quantum systems approaches the level needed for useful computation, the physical hardware underlying the quantum systems is becoming increasingly complex. It is already becoming impractical to manually code control for the larger hardware implementations. In this chapter, we will employ an approach to the problem of system control that parallels compiler design for a classical computer. We will start with a candidate quantum computing technology, the surface electrode ion trap, and build a system instruction language which can be generated from a simple machine-independent programming language via compilation. We incorporate compile time generation of ion routing that separates the algorithm description from the physical geometry of the hardware. Extending this approach to automatic routing at run time allows for automated initialization of qubit number and placement and additionally allows for automated recovery after catastrophic events such as qubit loss. To show that these systems can handle real hardware, we present a simple demonstration system that routes two ions around a multi-zone ion trap and handles ion loss and ion placement. While we will mainly use examples from transport-based ion trap quantum computing, many of the issues and solutions are applicable to other architectures.

  19. LQC control for the Mini-Mast experiment

    NASA Technical Reports Server (NTRS)

    Montgomery, R. C.; Ghosh, D.

    1988-01-01

    The Mini-Mast system is briefly reviewed, and results of a simulation study of the LQG control for the Mini-Mast experiment are reported. In particular, attention is given to problems and limitations related to the testing of control laws using reaction mass actuators, such as accounting for force and stroke limits of these devices. The local controller used in the study and the algorithm for converting the force commands of the LQG algorithm to position commands for the reaction mass device are described. It is shown that the LQG generated damping is reduced when a local controller is used and the position command is not saturated; it drops still further when the position command is saturated.

  20. 2. VIEW OF THE EXPERIMENT CONTROL PANEL IN 1970. THE ...

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

    2. VIEW OF THE EXPERIMENT CONTROL PANEL IN 1970. THE NUCLEAR SAFETY GROUP CONDUCTED ABOUT 1,700 CRITICAL MASS EXPERIMENTS USING URANIUM AND PLUTONIUM IN SOLUTIONS (900 TESTS), COMPACTED POWDER (300), AND METALLIC FORMS (500). ALL 1,700 CRITICALITY ASSEMBLIES WERE CONTROLLED FROM THIS PANEL. - Rocky Flats Plant, Critical Mass Laboratory, Intersection of Central Avenue & 86 Drive, Golden, Jefferson County, CO

  1. Sexual experience and responses to a birth control film.

    PubMed

    Herold, E S; Thomas, R E

    1980-02-01

    The objective of this research was to examine the relationship between sexual experience and sexual and contraceptive attitudinal responses to a birth control film. A questionnaire was administered immediately before and after showing a birth control film to 103 college females. Subjects were classified into three groups according to their sexual and contraceptive experience. With perceived change measures, it was found that the film reinforced sexual and contraceptive beliefs. Significant group differences were found regarding reinforcement of sexual attitudes but not for contraceptive attitudes.

  2. Biological control experiment of excess propagation of Cyclops for drinking water security.

    PubMed

    Lin, Tao; Cui, Fu-Yi; Liu, Dong-Mei

    2007-01-01

    Cyclops of zooplankton propagated excessively in eutrophic water body and could not be effectively inactivated by the conventional disinfections process like chlorination due to its stronger resistance to oxidation. In this study, an ecological project was put forward for the excess propagation control of Cyclops by stocking the filter-feeding fishes such as silver carp and bighead carp under the condition of no extraneous nutrient feeding. The results of experiments with different stocking biomass showed that the propagation of Cyclops could be controlled effectively, and the water quality was improved simultaneously by impacting on nutriment level and plankton community structure at proper stocking density of 30 g/m3 of water. The growth of Cyclops may not be effectually controlled with lower biomass of fish (10 g), and the natural food chain relation may be destroyed for Cyclops dying out in water while the intense stocking of 120 g per cubic meter of water. In addition, the high predator pressure may accelerate supplemental rate of nutrients from bottom sediments to water body to add the content of total nitrogen and phosphorus in water.

  3. [Tobacco control: an intersectorial experience in Tunja (Colombia)].

    PubMed

    Panader-Torres, Adriana; Agudelo-Cely, Nancy Aurora; Bolívar-Suárez, Yolima; Cárdenas-Cárdenas, Luz Mery

    2014-01-01

    Tobacco control in Colombia is regulated by Law 1335 of 2009. The implementation and monitoring of the provisions of this law require strengthening of intersectorial work at the local level. This field note presents an intersectorial work experience that was carried out in the municipality of Tunja (Colombia) to improve tobacco control. The Respirarte Group was established. This group consists of an intersectorial team composed of 15 institutions. The Respirarte Group achieved the following political and community actions: signing of an agreement on tobacco control by government actors, expedition of a local decree to comply with Law 1335 in the municipality, provision of information and communication, and social mobilization and monitoring. This experience serves as a national and international reference and its lessons could be used in the approach to other public health problems. Copyright © 2014 SESPAS. Published by Elsevier Espana. All rights reserved.

  4. Profile control simulations and experiments on TCV: a controller test environment and results using a model-based predictive controller

    NASA Astrophysics Data System (ADS)

    Maljaars, E.; Felici, F.; Blanken, T. C.; Galperti, C.; Sauter, O.; de Baar, M. R.; Carpanese, F.; Goodman, T. P.; Kim, D.; Kim, S. H.; Kong, M.; Mavkov, B.; Merle, A.; Moret, J. M.; Nouailletas, R.; Scheffer, M.; Teplukhina, A. A.; Vu, N. M. T.; The EUROfusion MST1-team; The TCV-team

    2017-12-01

    The successful performance of a model predictive profile controller is demonstrated in simulations and experiments on the TCV tokamak, employing a profile controller test environment. Stable high-performance tokamak operation in hybrid and advanced plasma scenarios requires control over the safety factor profile (q-profile) and kinetic plasma parameters such as the plasma beta. This demands to establish reliable profile control routines in presently operational tokamaks. We present a model predictive profile controller that controls the q-profile and plasma beta using power requests to two clusters of gyrotrons and the plasma current request. The performance of the controller is analyzed in both simulation and TCV L-mode discharges where successful tracking of the estimated inverse q-profile as well as plasma beta is demonstrated under uncertain plasma conditions and the presence of disturbances. The controller exploits the knowledge of the time-varying actuator limits in the actuator input calculation itself such that fast transitions between targets are achieved without overshoot. A software environment is employed to prepare and test this and three other profile controllers in parallel in simulations and experiments on TCV. This set of tools includes the rapid plasma transport simulator RAPTOR and various algorithms to reconstruct the plasma equilibrium and plasma profiles by merging the available measurements with model-based predictions. In this work the estimated q-profile is merely based on RAPTOR model predictions due to the absence of internal current density measurements in TCV. These results encourage to further exploit model predictive profile control in experiments on TCV and other (future) tokamaks.

  5. Thermal control surfaces on the MSFC LDEF experiments

    NASA Technical Reports Server (NTRS)

    Wilkes, Donald R.; Whitaker, Ann F.; Zwiener, James M.; Linton, Roger C.; Shular, David; Peters, Palmer N.; Gregory, John C.

    1992-01-01

    There were five Marshall Space Flight Center (MSFC) experiments on the LDEF. Each of those experiments carried thermal control surfaces either as test samples or as operational surfaces. These materials experienced varying degrees of mechanical and optical damage. Some materials were virtually unchanged by the extended exposure while others suffered extensive degradation. The synergistic effects due to the constituents of the space environment are evident in the diversity of these material changes. The sample complement for the MSFC experiments is described along with results of the continuing analyses efforts.

  6. Controlled Experiment Replication in Evaluation of E-Learning System's Educational Influence

    ERIC Educational Resources Information Center

    Grubisic, Ani; Stankov, Slavomir; Rosic, Marko; Zitko, Branko

    2009-01-01

    We believe that every effectiveness evaluation should be replicated at least in order to verify the original results and to indicate evaluated e-learning system's advantages or disadvantages. This paper presents the methodology for conducting controlled experiment replication, as well as, results of a controlled experiment and an internal…

  7. Theory of single-molecule controlled rotation experiments, predictions, tests, and comparison with stalling experiments in F1-ATPase.

    PubMed

    Volkán-Kacsó, Sándor; Marcus, Rudolph A

    2016-10-25

    A recently proposed chemomechanical group transfer theory of rotary biomolecular motors is applied to treat single-molecule controlled rotation experiments. In these experiments, single-molecule fluorescence is used to measure the binding and release rate constants of nucleotides by monitoring the occupancy of binding sites. It is shown how missed events of nucleotide binding and release in these experiments can be corrected using theory, with F 1 -ATP synthase as an example. The missed events are significant when the reverse rate is very fast. Using the theory the actual rate constants in the controlled rotation experiments and the corrections are predicted from independent data, including other single-molecule rotation and ensemble biochemical experiments. The effective torsional elastic constant is found to depend on the binding/releasing nucleotide, and it is smaller for ADP than for ATP. There is a good agreement, with no adjustable parameters, between the theoretical and experimental results of controlled rotation experiments and stalling experiments, for the range of angles where the data overlap. This agreement is perhaps all the more surprising because it occurs even though the binding and release of fluorescent nucleotides is monitored at single-site occupancy concentrations, whereas the stalling and free rotation experiments have multiple-site occupancy.

  8. An integrative, experience-based theory of attentional control.

    PubMed

    Wilder, Matthew H; Mozer, Michael C; Wickens, Christopher D

    2011-02-09

    Although diverse, theories of visual attention generally share the notion that attention is controlled by some combination of three distinct strategies: (1) exogenous cuing from locally contrasting primitive visual features, such as abrupt onsets or color singletons (e.g., L. Itti, C. Koch, & E. Neiber, 1998), (2) endogenous gain modulation of exogenous activations, used to guide attention to task-relevant features (e.g., V. Navalpakkam & L. Itti, 2007; J. Wolfe, 1994, 2007), and (3) endogenous prediction of likely locations of interest, based on task and scene gist (e.g., A. Torralba, A. Oliva, M. Castelhano, & J. Henderson, 2006). However, little work has been done to synthesize these disparate theories. In this work, we propose a unifying conceptualization in which attention is controlled along two dimensions: the degree of task focus and the contextual scale of operation. Previously proposed strategies-and their combinations-can be viewed as instances of this one mechanism. Thus, this theory serves not as a replacement for existing models but as a means of bringing them into a coherent framework. We present an implementation of this theory and demonstrate its applicability to a wide range of attentional phenomena. The model accounts for key results in visual search with synthetic images and makes reasonable predictions for human eye movements in search tasks involving real-world images. In addition, the theory offers an unusual perspective on attention that places a fundamental emphasis on the role of experience and task-related knowledge.

  9. On-orbit experience with the HEAO attitude control subsystem

    NASA Technical Reports Server (NTRS)

    Hoffman, D. P.; Berkery, E. A.

    1978-01-01

    The first satellite (HEAO-1) in the High Energy Astronomy Observatory Program series was launched successfully on Aug. 12, 1977. To date it has completed over nine months of orbital operation in a science data gathering mode. During this period all attitude control modes have been exercised and all primary mission objectives have been achieved. This paper highlights the characteristics of the attitude control subsystem design and compares the predicted performance with the actual flight operations experience. Environmental disturbance modeling, component hardware/software characteristics, and overall attitude control performance are reviewed and are found to compare very well with the prelaunch analytical predictions. Brief comments are also included regarding the operations aspects of the attitude control subsystem. The experience in this regard demonstrates the effectiveness of the design flexibility afforded by the presence of a general purpose digital processor in the subsystem flight hardware implementation.

  10. Skylab D024 thermal control coatings and polymeric films experiment

    NASA Technical Reports Server (NTRS)

    Lehn, William L.; Hurley, Charles J.

    1992-01-01

    The Skylab D024 Thermal Control Coatings and Polymeric Films Experiment was designed to determine the effects of the external Skylab space environment on the performance and properties of a wide variety of selected thermal control coatings and polymeric films. Three duplicate sets of thermal control coatings and polymeric films were exposed to the Skylab space environment for varying periods of time during the mission. The specimens were retrieved by the astronauts during extravehicular activities (EVA) and placed in hermetically sealed return containers, recovered, and returned to the Wright Laboratory/Materials Laboratory/WPAFB, Ohio for analysis and evaluation. Postflight analysis of the three sets of recovered thermal control coatings indicated that measured changes in specimen thermo-optical properties were due to a combination of excessive contamination and solar degradation of the contaminant layer. The degree of degradation experienced over-rode, obscured, and compromised the measurement of the degradation of the substrate coatings themselves. Results of the analysis of the effects of exposure on the polymeric films and the contamination observed are also presented. The D024 results were used in the design of the LDEF M0003-5 Thermal Control Materials Experiment. The results are presented here to call to the attention of the many other LDEF experimenters the wealth of directly related, low earth orbit, space environmental exposure data that is available from the ten or more separate experiments that were conducted during the Skylab mission. Results of these experiments offer data on the results of low altitude space exposure on materials recovered from space with exposure longer than typical STS experiments for comparison with the LDEF results.

  11. Performance of active vibration control technology: the ACTEX flight experiments

    NASA Astrophysics Data System (ADS)

    Nye, T. W.; Manning, R. A.; Qassim, K.

    1999-12-01

    This paper discusses the development and results of two intelligent structures space-flight experiments, each of which could affect architecture designs of future spacecraft. The first, the advanced controls technology experiment I (ACTEX I), is a variable stiffness tripod structure riding as a secondary payload on a classified spacecraft. It has been operating well past its expected life since becoming operational in 1996. Over 60 on-orbit experiments have been run on the ACTEX I flight experiment. These experiments form the basis for in-space controller design problems and for concluding lifetime/reliability data on the active control components. Transfer functions taken during the life of ACTEX I have shown consistent predictability and stability in structural behavior, including consistency with those measurements taken on the ground prior to a three year storage period and the launch event. ACTEX I can change its modal characteristics by employing its dynamic change mechanism that varies preloads in portions of its structure. Active control experiments have demonstrated maximum vibration reductions of 29 dB and 16 dB in the first two variable modes of the system, while operating over a remarkable on-orbit temperature range of -80 °C to 129 °C. The second experiment, ACTEX II, was successfully designed, ground-tested, and integrated on an experimental Department of Defense satellite prior to its loss during a launch vehicle failure in 1995. ACTEX II also had variable modal behavior by virtue of a two-axis gimbal and added challenges of structural flexibility by being a large deployable appendage. Although the loss of ACTEX II did not provide space environment experience, ground testing resulted in space qualifying the hardware and demonstrated 21 dB, 14 dB, and 8 dB reductions in amplitude of the first three primary structural modes. ACTEX II could use either active and/or passive techniques to affect vibration suppression. Both experiments trailblazed

  12. An Experiment in Linguistic Synthesis with a Fuzzy Logic Controller

    ERIC Educational Resources Information Center

    Mamdani, E. H.; Assilian, S.

    1975-01-01

    This paper describes an experiment on the "linguistic" synthesis of a controller for a model industrial plant (a steam engine). Fuzzy logic is used to convert heuristic control rules stated by a human operator into an automatic control strategy. (Author)

  13. Development of a New Hypersonic Shock Tunnel Facility to Investigate Electromagnetic Energy Addition for Flow Control and Basic Supersonic Combustion

    NASA Astrophysics Data System (ADS)

    Toro, P. G. P.; Minucci, M. A. S.; Chanes, J. B.; Pereira, A. L.; Nagamatsu, H. T.

    2006-05-01

    A new 0.6-m. diameter Hypersonic Shock Tunnel is been designed, fabricated and will be installed at the Laboratory of Aerothermodynamics and Hypersonics IEAv-CTA, Brazil. The brand new hypersonic facility, designated as T3, is primarily intended to be used as an important tool in the investigation of supersonic combustion management and of electromagnetic energy addition for flow control. The design of the runnel enables relatively long test times, 2-10 milliseconds, suitable for basic supersonic combustion and energy addition by laser experiments. Free stream Mach numbers ranging from 6 to 25 can be produced and stagnation pressures and temperatures of 200 atm. and 5,500 K, respectively, can be generated. Shadowgraph and schlieren optical techniques will be used for flow visualization and the new facility is expected to be commissioned by the end of 2006.

  14. Update on the DIII-D ECH system: experiments, gyrotrons, advanced diagnostics, and controls

    NASA Astrophysics Data System (ADS)

    Lohr, John; Brambila, Rigoberto; Cengher, Mirela; Gorelov, Yuri; Grosnickle, William; Moeller, Charles; Ponce, Dan; Torrezan, Antonio; Ives, Lawrence; Reed, Michael; Blank, Monica; Felch, Kevin; Parisuaña, Claudia; LeViness, Alexandra

    2017-08-01

    The ECH system on DIII-D is continuing to be upgraded, while simultaneously being operated nearly daily for plasma experiments. The latest major hardware addition is a new 117.5 GHz gyrotron, which generated 1.7 MW for short pulses during factory testing. A new gyrotron control system based on Field Programmable Gate Array (FPGA) technology with very high speed system data acquisition has significantly increased the flexibility and reliability of individual gyrotron operation. We have improved the performance of the fast mirror scanning, both by increasing the scan speeds and by adding new algorithms for controlling the aiming using commands generated by the Plasma Control System (PCS). The system is used for transport studies, ELM control, current profile control, non-inductive current generation, suppression of MHD modes, startup assist, plasma density control, and other applications. A program of protective measures, which has been in place for more than two years, has eliminated damage to hardware and diagnostics caused by overdense operation. Other activities not directly related to fusion research have used the ECH system to test components, study methods for improving production of semiconductor junctions and materials, and test the feasibility of using ground based microwave systems to power satellites into orbit.

  15. Decentralized control experiments on the JPL flexible spacecraft

    NASA Technical Reports Server (NTRS)

    Ozguner, U.; Ossman, K.; Donne, J.; Boesch, M.; Ahmed, A.

    1990-01-01

    Decentralized control experiments were successfully demonstrated for the JPL/AFAL Flexible Structure. A simulation package using MATRIXx showed strong correlation between the simulations and experimental result, while providing a means for test and debug of the various control strategies. Implementation was simplified by a modular software design that was easily transported from the simulation environment to the experimental environment. Control designs worked well for suppression of the dominant modes of the structure. Static decentralized output feedback dampened the excited modes of the structure, but sometimes excited higher order modes upon startup of the controller. A second-order frequency shaping controller helped to eliminate excitation of the higher order modes by attenuating high frequencies in the control effort. However, it also resulted in slightly longer settling times.

  16. Apollo experience report: Guidance and control systems. Lunar module stabilization and control system

    NASA Technical Reports Server (NTRS)

    Shelton, D. H.

    1975-01-01

    A brief functional description of the Apollo lunar module stabilization and control subsystem is presented. Subsystem requirements definition, design, development, test results, and flight experiences are discussed. Detailed discussions are presented of problems encountered and the resulting corrective actions taken during the course of assembly-level testing, integrated vehicle checkout and test, and mission operations. Although the main experiences described are problem oriented, the subsystem has performed satisfactorily in flight.

  17. Experiments in teleoperator and autonomous control of space robotic vehicles

    NASA Technical Reports Server (NTRS)

    Alexander, Harold L.

    1990-01-01

    A research program and strategy are described which include fundamental teleoperation issues and autonomous-control issues of sensing and navigation for satellite robots. The program consists of developing interfaces for visual operation and studying the consequences of interface designs as well as developing navigation and control technologies based on visual interaction. A space-robot-vehicle simulator is under development for use in virtual-environment teleoperation experiments and neutral-buoyancy investigations. These technologies can be utilized in a study of visual interfaces to address tradeoffs between head-tracking and manual remote cameras, panel-mounted and helmet-mounted displays, and stereoscopic and monoscopic display systems. The present program can provide significant data for the development of control experiments for autonomously controlled satellite robots.

  18. Development of electrical feedback controlled heat pipes and the advanced thermal control flight experiment

    NASA Technical Reports Server (NTRS)

    Bienert, W. B.

    1974-01-01

    The development and characteristics of electrical feedback controlled heat pipes (FCHP) are discussed. An analytical model was produced to describe the performance of the FCHP under steady state and transient conditions. An advanced thermal control flight experiment was designed to demonstrate the performance of the thermal control component in a space environment. The thermal control equipment was evaluated on the ATS-F satellite to provide performance data for the components and to act as a thermal control system which can be used to provide temperature stability of spacecraft components in future applications.

  19. Mathematical inference and control of molecular networks from perturbation experiments

    NASA Astrophysics Data System (ADS)

    Mohammed-Rasheed, Mohammed

    in order to affect the time evolution of molecular activity in a desirable manner. In this proposal, we address both the inference and control problems of GRNs. In the first part of the thesis, we consider the control problem. We assume that we are given a general topology network structure, whose dynamics follow a discrete-time Markov chain model. We subsequently develop a comprehensive framework for optimal perturbation control of the network. The aim of the perturbation is to drive the network away from undesirable steady-states and to force it to converge to a unique desirable steady-state. The proposed framework does not make any assumptions about the topology of the initial network (e.g., ergodicity, weak and strong connectivity), and is thus applicable to general topology networks. We define the optimal perturbation as the minimum-energy perturbation measured in terms of the Frobenius norm between the initial and perturbed networks. We subsequently demonstrate that there exists at most one optimal perturbation that forces the network into the desirable steady-state. In the event where the optimal perturbation does not exist, we construct a family of sub-optimal perturbations that approximate the optimal solution arbitrarily closely. In the second part of the thesis, we address the inference problem of GRNs from time series data. We model the dynamics of the molecules using a system of ordinary differential equations corrupted by additive white noise. For large-scale networks, we formulate the inference problem as a constrained maximum likelihood estimation problem. We derive the molecular interactions that maximize the likelihood function while constraining the network to be sparse. We further propose a procedure to recover weak interactions based on the Bayesian information criterion. For small-size networks, we investigated the inference of a globally stable 7-gene melanoma genetic regulatory network from genetic perturbation experiments. We considered five

  20. Evaluating vortex generator jet experiments for turbulent flow separation control

    NASA Astrophysics Data System (ADS)

    von Stillfried, F.; Kékesi, T.; Wallin, S.; Johansson, A. V.

    2011-12-01

    Separating turbulent boundary-layers can be energized by streamwise vortices from vortex generators (VG) that increase the near wall momentum as well as the overall mixing of the flow so that flow separation can be delayed or even prevented. In general, two different types of VGs exist: passive vane VGs (VVG) and active VG jets (VGJ). Even though VGs are already successfully used in engineering applications, it is still time-consuming and computationally expensive to include them in a numerical analysis. Fully resolved VGs in a computational mesh lead to a very high number of grid points and thus, computational costs. In addition, computational parameter studies for such flow control devices take much time to set-up. Therefore, much of the research work is still carried out experimentally. KTH Stockholm develops a novel VGJ model that makes it possible to only include the physical influence in terms of the additional stresses that originate from the VGJs without the need to locally refine the computational mesh. Such a modelling strategy enables fast VGJ parameter variations and optimization studies are easliy made possible. For that, VGJ experiments are evaluated in this contribution and results are used for developing a statistical VGJ model.

  1. Experiments on Socio-Technical Systems: The Problem of Control.

    PubMed

    Kroes, Peter

    2016-06-01

    My aim is to question whether the introduction of new technologies in society may be considered to be genuine experiments. I will argue that they are not, at least not in the sense in which the notion of experiment is being used in the natural and social sciences. If the introduction of a new technology in society is interpreted as an experiment, then we are dealing with a notion of experiment that differs in an important respect from the notion of experiment as used in the natural and social sciences. This difference shows itself most prominently when the functioning of the new technological system is not only dependent on technological hardware but also on social 'software', that is, on social institutions such as appropriate laws, and actions of operators of the new technological system. In those cases we are not dealing with 'simply' the introduction of a new technology, but with the introduction of a new socio-technical system. I will argue that if the introduction of a new socio-technical system is considered to be an experiment, then the relation between the experimenter and the system on which the experiment is performed differs significantly from the relation in traditional experiments in the natural and social sciences. In the latter experiments it is assumed that the experimenter is not part of the experimental system and is able to intervene in and control the experimental system from the outside. With regard to the introduction of new socio-technical systems the idea that there is an experimenter outside the socio-technical system who intervenes in and controls that system becomes problematic. From that perspective we are dealing with a different kind of experiment.

  2. Geo-engineering experiments in two urban ponds to control eutrophication.

    PubMed

    Waajen, Guido; van Oosterhout, Frank; Douglas, Grant; Lürling, Miquel

    2016-06-15

    Many urban ponds experience detrimental algal blooms as the result of eutrophication. During a two year field experiment, the efficacy of five in situ treatments to mitigate eutrophication effects in urban ponds was studied. The treatments targeted the sediment phosphorus release and were intended to switch the ponds from a turbid phytoplankton-dominated state to a clear-water state with a low phytoplankton biomass. Two eutrophic urban ponds were each divided into six compartments (300-400 m(2); 210-700 m(3)). In each pond the following treatments were tested: dredging in combination with biomanipulation (involving fish biomass control and the introduction of macrophytes) with and without the addition of the flocculant polyaluminiumchloride, interception and reduction of sediment phosphorus release with lanthanum-modified bentonite (Phoslock(®)) in combination with biomanipulation with and without polyaluminiumchloride; biomanipulation alone; and a control. Trial results support the hypothesis that the combination of biomanipulation and measures targeting the sediment phosphorus release can be effective in reducing the phytoplankton biomass and establishing and maintaining a clear-water state, provided the external phosphorus loading is limited. During the experimental period dredging combined with biomanipulation showed mean chlorophyll-a concentrations of 5.3 and 6.2 μg L(-1), compared to 268.9 and 52.4 μg L(-1) in the control compartments. Lanthanum-modified bentonite can be an effective alternative to dredging and in combination with biomanipulation it showed mean chlorophyll-a concentrations of 5.9 and 7.6 μg L(-1). Biomanipulation alone did not establish a clear-water state or only during a limited period. As the two experimental sites differed in their reaction to the treatments, it is important to choose the most promising treatment depending on site specific characteristics. In recovering the water quality status of urban ponds, continuing

  3. Autonomous learning based on cost assumptions: theoretical studies and experiments in robot control.

    PubMed

    Ribeiro, C H; Hemerly, E M

    2000-02-01

    Autonomous learning techniques are based on experience acquisition. In most realistic applications, experience is time-consuming: it implies sensor reading, actuator control and algorithmic update, constrained by the learning system dynamics. The information crudeness upon which classical learning algorithms operate make such problems too difficult and unrealistic. Nonetheless, additional information for facilitating the learning process ideally should be embedded in such a way that the structural, well-studied characteristics of these fundamental algorithms are maintained. We investigate in this article a more general formulation of the Q-learning method that allows for a spreading of information derived from single updates towards a neighbourhood of the instantly visited state and converges to optimality. We show how this new formulation can be used as a mechanism to safely embed prior knowledge about the structure of the state space, and demonstrate it in a modified implementation of a reinforcement learning algorithm in a real robot navigation task.

  4. Additive Manufacturing of Shape Memory Alloys

    NASA Astrophysics Data System (ADS)

    Van Humbeeck, Jan

    2018-04-01

    Selective Laser Melting (SLM) is an additive manufacturing production process, also called 3D printing, in which functional, complex parts are produced by selectively melting patterns in consecutive layers of powder with a laser beam. The pattern the laser beam is following is controlled by software that calculates the pattern by slicing a 3D CAD model of the part to be constructed. Apart from SLM, also other additive manufacturing techniques such as EBM (Electron Beam Melting), FDM (Fused Deposition Modelling), WAAM (Wire Arc Additive Manufacturing), LENS (Laser Engineered Net Shaping such as Laser Cladding) and binder jetting allow to construct complete parts layer upon layer. But since more experience of AM of shape memory alloys is collected by SLM, this paper will overview the potentials, limits and problems of producing NiTi parts by SLM.

  5. Beyond "Witnessing": Children's Experiences of Coercive Control in Domestic Violence and Abuse.

    PubMed

    Callaghan, Jane E M; Alexander, Joanne H; Sixsmith, Judith; Fellin, Lisa Chiara

    2015-12-10

    Children's experiences and voices are underrepresented in academic literature and professional practice around domestic violence and abuse. The project "Understanding Agency and Resistance Strategies" (UNARS) addresses this absence, through direct engagement with children. We present an analysis from interviews with 21 children in the United Kingdom (12 girls and 9 boys, aged 8-18 years), about their experiences of domestic violence and abuse, and their responses to this violence. These interviews were analyzed using interpretive interactionism. Three themes from this analysis are presented: (a) "Children's experiences of abusive control," which explores children's awareness of controlling behavior by the adult perpetrator, their experience of that control, and its impact on them; (b) "Constraint," which explores how children experience the constraint associated with coercive control in situations of domestic violence; and (c) "Children as agents," which explores children's strategies for managing controlling behavior in their home and in family relationships. The article argues that, in situations where violence and abuse occur between adult intimate partners, children are significantly affected, and can be reasonably described as victims of abusive control. Recognizing children as direct victims of domestic violence and abuse would produce significant changes in the way professionals respond to them, by (a) recognizing children's experience of the impact of domestic violence and abuse; (b) recognizing children's agency, undermining the perception of them as passive "witnesses" or "collateral damage" in adult abusive encounters; and (c) strengthening professional responses to them as direct victims, not as passive witnesses to violence. © The Author(s) 2015.

  6. Experiences with Ada in an embedded system

    NASA Technical Reports Server (NTRS)

    Labaugh, Robert J.

    1988-01-01

    Recent experiences with using Ada in a real time environment are described. The application was the control system for an experimental robotic arm. The objectives of the effort were to experiment with developing embedded applications in Ada, evaluating the suitability of the language for the application, and determining the performance of the system. Additional objectives were to develop a control system based on the NASA/NBS Standard Reference Model for Telerobot Control System Architecture (NASREM) in Ada, and to experiment with the control laws and how to incorporate them into the NASREM architecture.

  7. Sensitivity of Arctic Permafrost Carbon in the Mackenzie River Basin: A substrate addition and incubation experiment

    NASA Astrophysics Data System (ADS)

    Hedgpeth, A.; Beilman, D.; Crow, S. E.

    2014-12-01

    Arctic soil organic matter (SOM) mineralization processes are fundamental to the functioning of high latitude soils in relation to nutrients, stability, and feedbacks to atmospheric CO2 and climate. The arctic permafrost zone covers 25% of the northern hemisphere and contains 1672Pg of soil carbon (C). 88% of this C currently resides in frozen soils that are vulnerable to environmental change. For instance, arctic growing seasons may be lengthened, resulting in an increase in plant productivity and rate of below ground labile C inputs as root exudates. Understanding controls on Arctic SOM dynamics requires recognition that labile C inputs have the potential to significantly affect mineralization of previously stable SOM, also known as 'priming effects'. We conducted a substrate addition incubation experiment to quantify and compare respiration in highly organic (42-48 %C) permafrost soils along a north-south transect in western Canada. Near surface soils (10-20 cm) were collected from permafrost peatland sites in the Mackenzie River Basin from 69.2-62.6°N. The surface soils are fairly young (Δ14C values > -140.0) and can be assumed to contain relatively reactive soil carbon. To assess whether addition of labile substrate alters SOM decomposition dynamics, 4.77-11.75 g of permafrost soil were spiked with 0.5 mg D-glucose g-1 soil and incubated at 5°C. A mass balance approach was used to determin substrate-induced respiration and preliminary results suggest a potential for positive priming in these C-rich soils. Baseline respiration rates from the three sites were similar (0.067-0.263 mg CO2 g-1 soil C) yet show some site-specific trends. The rate at which added substrate was utilized within these soils suggests that other factors besides temperature and soil C content are controlling substrate consumption and its effect on SOM decomposition. Microbial activity can be stimulated by substrate addition to such an extent that SOM turnover is enhanced, suggesting that

  8. Design of the EO-1 Pulsed Plasma Thruster Attitude Control Experiment

    NASA Technical Reports Server (NTRS)

    Zakrzwski, Charles; Sanneman, Paul; Hunt, Teresa; Blackman, Kathie; Bauer, Frank H. (Technical Monitor)

    2001-01-01

    The Pulsed Plasma Thruster (PPT) Experiment on the Earth Observing 1 (EO-1) spacecraft has been designed to demonstrate the capability of a new generation PPT to perform spacecraft attitude control. The PPT is a small, self-contained pulsed electromagnetic Propulsion system capable of delivering high specific impulse (900-1200 s), very small impulse bits (10-1000 micro N-s) at low average power (less than 1 to 100 W). EO-1 has a single PPT that can produce torque in either the positive or negative pitch direction. For the PPT in-flight experiment, the pitch reaction wheel will be replaced by the PPT during nominal EO-1 nadir pointing. A PPT specific proportional-integral-derivative (PID) control algorithm was developed for the experiment. High fidelity simulations of the spacecraft attitude control capability using the PPT were conducted. The simulations, which showed PPT control performance within acceptable mission limits, will be used as the benchmark for on-orbit performance. The flight validation will demonstrate the ability of the PPT to provide precision pointing resolution. response and stability as an attitude control actuator.

  9. Tank Pressure Control Experiment on the Space Shuttle

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The tank pressure control experiment is a demonstration of NASA intent to develop new technology for low-gravity management of the cryogenic fluids that will be required for future space systems. The experiment will use freon as the test fluid to measure the effects of jet-induced fluid mixing on storage tank pressure and will produce data on low-gravity mixing processes critical to the design of on-orbit cryogenic storage and resupply systems. Basic data on fluid motion and thermodynamics in low gravity is limited, but such data is critical to the development of space transfer vehicles and spacecraft resupply facilities. An in-space experiment is needed to obtain reliable data on fluid mixing and pressure control because none of the available microgravity test facilities provide a low enough gravity level for a sufficient duration to duplicate in-space flow patterns and thermal processes. Normal gravity tests do not represent the fluid behavior properly; drop-tower tests are limited in length of time available; aircraft low-gravity tests cannot provide the steady near-zero gravity level and long duration needed to study the subtle processes expected in space.

  10. EAGLE The controlled source experiment

    NASA Astrophysics Data System (ADS)

    Maguire, P. K. H.; Eagle Controlled Source Group

    2003-04-01

    In January 2003, a wide-angle reflection / refraction seismic project was carried out over the north-eastern section of the Main Ethiopian Rift as part of the international EAGLE (Ethiopia Afar Geoscientific Lithospheric Experiment) programme. EAGLE comprises a combination of passive and controlled source seismic experiments to determine the geometry and kinematics of a continental rift immediately prior to break-up, enabling the development of magmatic margin break-up models. A total of ˜900 seismic instruments were deployed along two 450km profiles, one along the axis of the Ethiopian Rift into the south-west corner of Afar; and a second across the rift, extending north and south across the uplifted, flood basalt covered, Ethiopian plateau. The two profiles intersect over the Nazret volcanic segment in the rift. This may be indicative of the transition from continental style rifting in which strain is accommodated on the rift bounding border faults, to a state where strain and magmatism have migrated to a narrow zone within the rift, a necessary pre-cursor to break-up. A further ˜300 instruments were deployed in a 100x100km^2 array around the intersection of the two profiles. A total of 16 borehole and 2 lake shots were fired into the network over a period of four days. The principal objectives of the controlled source project were to examine crustal strain, the distribution of crustal magmatic intrusions, the influence of pre-rift crustal property variations on rift development and also to provide a crustal seismic velocity distribution to improve images of the deep mantle, as well as earthquake locations derived from the EAGLE passive arrays.

  11. Effect of Additives on Green Sand Molding Properties using Design of Experiments and Taguchi's Quality Loss Function - An Experimental Study

    NASA Astrophysics Data System (ADS)

    Desai, Bhagyashree; Mokashi, Pavani; Anand, R. L.; Burli, S. B.; Khandal, S. V.

    2016-09-01

    The experimental study aims to underseek the effect of various additives on the green sand molding properties as a particular combination of additives could yield desired sand properties. The input parameters (factors) selected were water and powder (Fly ash, Coconut shell and Tamarind) in three levels. Experiments were planned using design of experiments (DOE). On the basis of plans, experiments were conducted to understand the behavior of sand mould properties such as compression strength, shear strength, permeability number with various additives. From the experimental results it could be concluded that the factors have significant effect on the sand properties as P-value found to be less than 0.05 for all the cases studied. The optimization based on quality loss function was also performed. The study revealed that the quality loss associated with the tamarind powder was lesser compared to other additives selected for the study. The optimization based on quality loss function and the parametric analysis using ANOVA suggested that the tamarind powder of 8 gm per Kg of molding sand and moisture content of 7% yield better properties to obtain sound castings.

  12. Control of nitrification/denitrification in an onsite two-chamber intermittently aerated membrane bioreactor with alkalinity and carbon addition: Model and experiment.

    PubMed

    Perera, Mahamalage Kusumitha; Englehardt, James D; Tchobanoglous, George; Shamskhorzani, Reza

    2017-05-15

    Denitrifying membrane bioreactors (MBRs) are being found useful in water reuse treatment systems, including net-zero water (nearly closed-loop), non-reverse osmosis-based, direct potable reuse (DPR) systems. In such systems nitrogen may need to be controlled in the MBR to meet the nitrate drinking water standard in the finished water. To achieve efficient nitrification and denitrification, the addition of alkalinity and external carbon may be required, and control of the carbon feed rate is then important. In this work, an onsite, two-chamber aerobic nitrifying/denitrifying MBR, representing one unit process of a net-zero water, non-reverse osmosis-based DPR system, was modeled as a basis for control of the MBR internal recycling rate, aeration rate, and external carbon feed rate. Specifically, a modification of the activated sludge model ASM2dSMP was modified further to represent the rate of recycling between separate aerobic and anoxic chambers, rates of carbon and alkalinity feed, and variable aeration schedule, and was demonstrated versus field data. The optimal aeration pattern for the modeled reactor configuration and influent matrix was found to be 30 min of aeration in a 2 h cycle (104 m 3 air/d per 1 m 3 /d average influent), to ultimately meet the nitrate drinking water standard. Optimal recycling ratios (inter-chamber flow to average daily flow) were found to be 1.5 and 3 during rest and mixing periods, respectively. The model can be used to optimize aeration pattern and recycling ratio in such MBRs, with slight modifications to reflect reactor configuration, influent matrix, and target nitrogen species concentrations, though some recalibration may be required. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. C-SIDE: The control-structure interaction demonstration experiment

    NASA Technical Reports Server (NTRS)

    Mohl, James B.; Davis, Hugh W.

    1993-01-01

    The Control-Structure Interaction Demonstration Experiment (C-SIDE) is sponsored by the Electro-Optics and Cryogenics Division of Ball Aerospace Systems Group. Our objective is to demonstrate methods of solution to structure control problems utilizing currently available hardware in a system that is an extension of our corporate experience. The larger space structures with which Ball has been associated are the SEASAT radar antenna, Shuttle Imaging Radar (SIR) -A, -B and -C antennas and the Radarsat spacecraft. The motivation for the C-SIDE configuration is to show that integration of active figure control in the radar's system-level design can relieve antenna mechanical design constraints. This presentation is primarily an introduction to the C-SIDE testbed. Its physical and functional layouts, and major components are described. The sensor is of special interest as it enables direct surface figure measurements from a remote location. The Remote Attitude Measurement System (RAMS) makes high-rate, unobtrusive measurements of many locations, several of which may be collocated easily with actuators. The control processor is a 386/25 executing a reduced order model-based algorithm with provision for residual mode filters to compensate for structure interaction. The actuators for the ground demonstration are non-contacting, linear force devices. Results presented illustrate some basic characteristics of control-structure interaction with this hardware. The testbed will be used for evaluation of current technologies and for research in several areas. A brief indication of the evolution of the C-SIDE is given at the conclusion.

  14. A Simple and Inexpensive Device for Slow, Controlled Addition of a Solution to a Reaction Mixture

    NASA Astrophysics Data System (ADS)

    Osvath, Peter

    1995-07-01

    A number of reactions require the slow and controlled addition of a solution containing one reagent to another. Attempting to control the flow rate over a number of hours using a conventional constant pressure addition funnel is a frustrating exercise; commercially available constant volume addition funnels are expensive and must be adjusted by trial and error each time a reaction is carried out. The use of an (expensive) peristaltic pump or syringe pump overcomes these problems but can introduce other complications. We have recently had occasion to carry out the synthesis of thioether macrocycles and cages requiring the slow and controlled addition of DMF solutions of (offensively odoriferous) thiols or (air-sensitive) thiolates to a reactant solution under nitrogen(1), Although the use of a syringe pump was called for, there are obvious difficulties associated with purging the solution and assembling such an apparatus under nitrogen, and we report a simple and inexpensive solution. A Male Luer Lock tip (recovered from a broken syringe) was sweated onto the flattened tip of a pressure-equalizing addition funnel and a syringe needle was attached. Judicious selection of needle length, bore size, and reactant volume can be used to control the addition time simply and reproducibly. With a 250-mL funnel, the flow rate changes by <25% from the beginning to the end of the addition. (In fact, a reduction in the rate of addition may even be advantageous as the reaction proceeds, the reagent in the receiving flask is consumed, its concentration drops, and the rate of reaction will decrease). A piece of fine Teflon tubing of appropriate length attached to the needle can be used to reduce the flow rate even further, but this is only necessary for very slow rates of addition. For example, the time of addition of 200 mL, of an ethanolic solution could be varied from approximately 5 minutes (150mm/17 gauge) to approximately 5 h (200mm/22 gauge), and once the addition time for a

  15. Inhibitory Control, but Not Prolonged Object-Related Experience Appears to Affect Physical Problem-Solving Performance of Pet Dogs.

    PubMed

    Müller, Corsin A; Riemer, Stefanie; Virányi, Zsófia; Huber, Ludwig; Range, Friederike

    2016-01-01

    Human infants develop an understanding of their physical environment through playful interactions with objects. Similar processes may influence also the performance of non-human animals in physical problem-solving tasks, but to date there is little empirical data to evaluate this hypothesis. In addition or alternatively to prior experiences, inhibitory control has been suggested as a factor underlying the considerable individual differences in performance reported for many species. Here we report a study in which we manipulated the extent of object-related experience for a cohort of dogs (Canis familiaris) of the breed Border Collie over a period of 18 months, and assessed their level of inhibitory control, prior to testing them in a series of four physical problem-solving tasks. We found no evidence that differences in object-related experience explain variability in performance in these tasks. It thus appears that dogs do not transfer knowledge about physical rules from one physical problem-solving task to another, but rather approach each task as a novel problem. Our results, however, suggest that individual performance in these tasks is influenced in a complex way by the subject's level of inhibitory control. Depending on the task, inhibitory control had a positive or a negative effect on performance and different aspects of inhibitory control turned out to be the best predictors of individual performance in the different tasks. Therefore, studying the interplay between inhibitory control and problem-solving performance will make an important contribution to our understanding of individual and species differences in physical problem-solving performance.

  16. Inhibitory Control, but Not Prolonged Object-Related Experience Appears to Affect Physical Problem-Solving Performance of Pet Dogs

    PubMed Central

    Müller, Corsin A.; Riemer, Stefanie; Virányi, Zsófia; Huber, Ludwig; Range, Friederike

    2016-01-01

    Human infants develop an understanding of their physical environment through playful interactions with objects. Similar processes may influence also the performance of non-human animals in physical problem-solving tasks, but to date there is little empirical data to evaluate this hypothesis. In addition or alternatively to prior experiences, inhibitory control has been suggested as a factor underlying the considerable individual differences in performance reported for many species. Here we report a study in which we manipulated the extent of object-related experience for a cohort of dogs (Canis familiaris) of the breed Border Collie over a period of 18 months, and assessed their level of inhibitory control, prior to testing them in a series of four physical problem-solving tasks. We found no evidence that differences in object-related experience explain variability in performance in these tasks. It thus appears that dogs do not transfer knowledge about physical rules from one physical problem-solving task to another, but rather approach each task as a novel problem. Our results, however, suggest that individual performance in these tasks is influenced in a complex way by the subject’s level of inhibitory control. Depending on the task, inhibitory control had a positive or a negative effect on performance and different aspects of inhibitory control turned out to be the best predictors of individual performance in the different tasks. Therefore, studying the interplay between inhibitory control and problem-solving performance will make an important contribution to our understanding of individual and species differences in physical problem-solving performance. PMID:26863141

  17. Comparison of GWAS models to identify non-additive genetic control of flowering time in sunflower hybrids.

    PubMed

    Bonnafous, Fanny; Fievet, Ghislain; Blanchet, Nicolas; Boniface, Marie-Claude; Carrère, Sébastien; Gouzy, Jérôme; Legrand, Ludovic; Marage, Gwenola; Bret-Mestries, Emmanuelle; Munos, Stéphane; Pouilly, Nicolas; Vincourt, Patrick; Langlade, Nicolas; Mangin, Brigitte

    2018-02-01

    This study compares five models of GWAS, to show the added value of non-additive modeling of allelic effects to identify genomic regions controlling flowering time of sunflower hybrids. Genome-wide association studies are a powerful and widely used tool to decipher the genetic control of complex traits. One of the main challenges for hybrid crops, such as maize or sunflower, is to model the hybrid vigor in the linear mixed models, considering the relatedness between individuals. Here, we compared two additive and three non-additive association models for their ability to identify genomic regions associated with flowering time in sunflower hybrids. A panel of 452 sunflower hybrids, corresponding to incomplete crossing between 36 male lines and 36 female lines, was phenotyped in five environments and genotyped for 2,204,423 SNPs. Intra-locus effects were estimated in multi-locus models to detect genomic regions associated with flowering time using the different models. Thirteen quantitative trait loci were identified in total, two with both model categories and one with only non-additive models. A quantitative trait loci on LG09, detected by both the additive and non-additive models, is located near a GAI homolog and is presented in detail. Overall, this study shows the added value of non-additive modeling of allelic effects for identifying genomic regions that control traits of interest and that could participate in the heterosis observed in hybrids.

  18. Morphological control in polymer solar cells using low-boiling-point solvent additives

    NASA Astrophysics Data System (ADS)

    Mahadevapuram, Rakesh C.

    In the global search for clean, renewable energy sources, organic photovoltaics (OPVs) have recently been given much attention. Popular modern-day OPVs are made from solution-processible, carbon-based polymers (e.g. the model poly(3-hexylthiophene) that are intimately blended with fullerene derivatives (e.g. [6,6]-phenyl-C71-butyric acid methyl ester) to form what is known as the dispersed bulk-heterojunction (BHJ). This BHJ architecture has produced some of the most efficient OPVs to date, with reports closing in on 10% power conversion efficiency. To push efficiencies further into double digits, many groups have identified the BHJ nanomorphology---that is, the phase separations and grain sizes within the polymer: fullerene composite---as a key aspect in need of control and improvement. As a result, many methods, including thermal annealing, slow-drying (solvent) annealing, vapor annealing, and solvent additives, have been developed and studied to promote BHJ self-organization. Processing organic photovoltaic (OPV) blend solutions with high-boiling-point solvent additives has recently been used for morphological control in BHJ OPV cells. Here we show that even low-boiling-point solvents can be effective additives. When P3HT:PCBM OPV cells were processed with a low-boiling-point solvent tetrahydrafuran as an additive in parent solvent o-dichlorobenzene, charge extraction increased leading to fill factors as high as 69.5%, without low work-function cathodes, electrode buffer layers or thermal treatment. This was attributed to PCBM demixing from P3HT domains and better vertical phase separation, as indicated by photoluminescence lifetimes, hole mobilities, and shunt leakage currents. Dependence on solvent parameters and applicability beyond P3HT system was also investigated.

  19. A feasibility study regarding the addition of a fifth control to a rotorcraft in-flight simulator

    NASA Technical Reports Server (NTRS)

    Turner, Simon; Andrisani, Dominick, II

    1992-01-01

    The addition of a large movable horizontal tail surface to the control system of a rotorcraft in-flight simulator being developed from a Sikorsky UH-60A Black Hawk Helicopter is evaluated. The capabilities of the control surface as a trim control and as an active control are explored. The helicopter dynamics are modeled using the Generic Helicopter simulation program developed by Sikorsky Aircraft. The effect of the horizontal tail on the helicopter trim envelope is examined by plotting trim maps of the aircraft attitude and controls as a function of the flight speed and horizontal tail incidence. The control power of the tail surface relative to that of the other controls is examined by comparing control derivatives extracted from the simulation program over the flight speed envelope. The horizontal tail's contribution as an active control is evaluated using an explicit model following control synthesis involving a linear model of the helicopter in steady, level flight at a flight speed of eighty knots. The horizontal tail is found to provide additional control flexibility in the longitudinal axis. As a trim control, it provides effective control of the trim pitch attitude at mid to high forward speeds. As an active control, the horizontal tail provides useful pitching moment generating capabilities at mid to high forward speeds.

  20. Designing a Hybrid Laminar-Flow Control Experiment: The CFD-Experiment Connection

    NASA Technical Reports Server (NTRS)

    Streett, C. L.

    2003-01-01

    The NASA/Boeing hybrid laminar flow control (HLFC) experiment, designed during 1993-1994 and conducted in the NASA LaRC 8-foot Transonic Pressure Tunnel in 1995, utilized computational fluid dynamics and numerical simulation of complex fluid mechanics to an unprecedented extent for the design of the test article and measurement equipment. CFD was used in: the design of the test wing, which was carried from definition of desired disturbance growth characteristics, through to the final airfoil shape that would produce those growth characteristics; the design of the suction-surface perforation pattern that produced enhanced crossflow-disturbance growth: and in the design of the hot-wire traverse system that produced minimal influence on measured disturbance growth. These and other aspects of the design of the test are discussed, after the historical and technical context of the experiment is described.

  1. User's Guide for ERB 7 Matrix. Volume 1: Experiment Description and Quality Control Report for Year 1

    NASA Technical Reports Server (NTRS)

    Tighe, R. J.; Shen, M. Y. H.

    1984-01-01

    The Nimbus 7 ERB MATRIX Tape is a computer program in which radiances and irradiances are converted into fluxes which are used to compute the basic scientific output parameters, emitted flux, albedo, and net radiation. They are spatially averaged and presented as time averages over one-day, six-day, and monthly periods. MATRIX data for the period November 16, 1978 through October 31, 1979 are presented. Described are the Earth Radiation Budget experiment, the Science Quality Control Report, Items checked by the MATRIX Science Quality Control Program, and Science Quality Control Data Analysis Report. Additional material from the detailed scientific quality control of the tapes which may be very useful to a user of the MATRIX tapes is included. Known errors and data problems and some suggestions on how to use the data for further climatologic and atmospheric physics studies are also discussed.

  2. Experience with synchronous and asynchronous digital control systems

    NASA Technical Reports Server (NTRS)

    Regenie, V. A.; Chacon, C. V.; Lock, W. P.

    1986-01-01

    Flight control systems have undergone a revolution since the days of simple mechanical linkages; presently the most advanced systems are full-authority, full-time digital systems controlling unstable aircraft. With the use of advanced control systems, the aerodynamic design can incorporate features that allow greater performance and fuel savings, as can be seen on the new Airbus design and advanced tactical fighter concepts. These advanced aircraft will be and are relying on the flight control system to provide the stability and handling qualities required for safe flight and to allow the pilot to control the aircraft. Various design philosophies have been proposed and followed to investigate system architectures for these advanced flight control systems. One major area of discussion is whether a multichannel digital control system should be synchronous or asynchronous. This paper addressed the flight experience at the Dryden Flight Research Facility of NASA's Ames Research Center with both synchronous and asynchronous digital flight control systems. Four different flight control systems are evaluated against criteria such as software reliability, cost increases, and schedule delays.

  3. Management Control Systems and Clinical Experience of Managers in Public Hospitals

    PubMed Central

    Naranjo-Gil, David

    2018-01-01

    Healthcare authorities are encouraging managers in hospitals to acquire clinical experience and knowledge in order to better carry out and coordinate healthcare service delivery. The main objective of this paper is to analyse how the clinical experience of hospital managers is related to public health institutions’ performance. It is proposed that the effect of the clinical experience on operative and financial organizational performance is indirect through the mediating variables of perceived utility of management information and horizontal management control system. This paper analyses how these variables impact hospital performance through the data from a survey sent to 364 hospital managers in Brazil. The results show that managers’ clinical experience is related to higher perceived utility of historical, financial, short-term, and internal information, but not with horizontal control adoption in hospitals. Furthermore, our results show that, in hospitals, perceived utility of forecasted, non-financial, long-term, and external managerial information positively affects hospitals’ financial performance, while adoption of horizontal control management positively affects operational performance. Through showing evidence that clinical background could explain the differences not only in hospital service management but also in information capabilities and management control processes, this study offer meaningful implications for healthcare authorities and hospital managers involved in the development and implementation of strategies in the health sector. PMID:29673192

  4. The service telemetry and control device for space experiment “GRIS”

    NASA Astrophysics Data System (ADS)

    Glyanenko, A. S.

    2016-02-01

    Problems of scientific devices control (for example, fine control of measuring paths), collecting auxiliary (service information about working capacity, conditions of experiment carrying out, etc.) and preliminary data processing are actual for any space device. Modern devices for space research it is impossible to imagine without devices that didn't use digital data processing methods and specialized or standard interfaces and computing facilities. For realization of these functions in “GRIS” experiment onboard ISS for purposes minimization of dimensions, power consumption, the concept “system-on-chip” was chosen and realized. In the programmable logical integrated scheme by Microsemi from ProASIC3 family with maximum capacity up to 3M system gates, the computing kernel and all necessary peripherals are created. In this paper we discuss structure, possibilities and resources the service telemetry and control device for “GRIS” space experiment.

  5. Microbial control of the gypsy moth in recently infested states: experiences and expectations

    Treesearch

    Timothy C. Tigner

    1985-01-01

    Experiences and expectations concerning microbial control of the gypsy moth in recently infested states are summarized. Initial experience included mixed results, but expectations remain optimistic. Public sentiment assures continued pressure for improvement in microbial control technology.

  6. Field experiments using SPEAR: a speech control system for UGVs

    NASA Astrophysics Data System (ADS)

    Chhatpar, Siddharth R.; Blanco, Chris; Czerniak, Jeffrey; Hoffman, Orin; Juneja, Amit; Pruthi, Tarun; Liu, Dongqing; Karlsen, Robert; Brown, Jonathan

    2009-05-01

    This paper reports on a Field Experiment carried out by the Human Research and Engineering Directorate at Ft. Benning to evaluate the efficacy of using speech to control an Unmanned Ground Vehicle (UGV) concurrently with a handcontroller. The SPEAR system, developed by Think-A-Move, provides speech-control of UGVs. The system picks up user-speech in the ear canal with an in-ear microphone. This property allows it to work efficiently in high-noise environments, where traditional speech systems, employing external microphones, fail. It has been integrated with an iRobot PackBot 510 with EOD kit. The integrated system allows the hand-controller to be supplemented with speech for concurrent control. At Ft. Benning, the integrated system was tested by soldiers from the Officer Candidate School. The Experiment had dual focus: 1) Quantitative measurement of the time taken to complete each station and the cognitive load on users; 2) Qualitative evaluation of ease-of-use and ergonomics through soldier-feedback. Also of significant benefit to Think-A-Move was soldier-feedback on the speech-command vocabulary employed: What spoken commands are intuitive, and how the commands should be executed, e.g., limited-motion vs. unlimited-motion commands. Overall results from the Experiment are reported in the paper.

  7. Control and monitoring of oxygen fugacity in piston cylinder experiments

    NASA Astrophysics Data System (ADS)

    Matjuschkin, Vladimir; Brooker, Richard A.; Tattitch, Brian; Blundy, Jon D.; Stamper, Charlotte C.

    2015-01-01

    We present a newly developed capsule design that resolves some common problems associated with the monitoring and control of oxygen fugacity ( fO2) in high-pressure piston cylinder experiments. The new fO2 control assembly consists of an AuPd outer capsule enclosing two inner capsules: one of AuPd capsule containing the experimental charge (including some water), and the other of Pt containing a solid oxygen buffer plus water. The inner capsules are separated by crushable alumina. The outer capsule is surrounded by a Pyrex sleeve to simultaneously minimise hydrogen loss from the cell and carbon infiltration from the graphite furnace. Controlled fO2 experiments using this cell design were carried out at 1.0 GPa and 1,000 °C. We used NiPd, CoPd and (Ni, Mg)O fO2 sensors, whose pressure sensitivity is well calibrated, to monitor the redox states achieved in experiments buffered by Re-ReO2, Ni-NiO and Co-CoO, respectively. Results for the fO2 sensors are in good agreement with the intended fO2 established by the buffer, demonstrating excellent control for durations of 24-48 h, with uncertainties less than ± 0.3 log bar units of fO2.

  8. Automated microbial metabolism laboratory. [design of advanced labeled release experiment based on single addition of soil and multiple sequential additions of media into test chambers

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The design and rationale of an advanced labeled release experiment based on single addition of soil and multiple sequential additions of media into each of four test chambers are outlined. The feasibility for multiple addition tests was established and various details of the methodology were studied. The four chamber battery of tests include: (1) determination of the effect of various atmospheric gases and selection of that gas which produces an optimum response; (2) determination of the effect of incubation temperature and selection of the optimum temperature for performing Martian biochemical tests; (3) sterile soil is dosed with a battery of C-14 labeled substrates and subjected to experimental temperature range; and (4) determination of the possible inhibitory effects of water on Martian organisms is performed initially by dosing with 0.01 ml and 0.5 ml of medium, respectively. A series of specifically labeled substrates are then added to obtain patterns in metabolic 14CO2 (C-14)O2 evolution.

  9. Methods for building an inexpensive computer-controlled olfactometer for temporally precise experiments

    PubMed Central

    Lundström, Johan N.; Gordon, Amy R.; Alden, Eva C.; Boesveldt, Sanne; Albrecht, Jessica

    2010-01-01

    Many human olfactory experiments call for fast and stable stimulus-rise times as well as exact and stable stimulus-onset times. Due to these temporal demands, an olfactometer is often needed. However, an olfactometer is a piece of equipment that either comes with a high price tag or requires a high degree of technical expertise to build and/or to run. Here, we detail the construction of an olfactometer that is constructed almost exclusively with “off-the-shelf” parts, requires little technical knowledge to build, has relatively low price tags, and is controlled by E-Prime, a turnkey-ready and easily-programmable software commonly used in psychological experiments. The olfactometer can present either solid or liquid odor sources, and it exhibits a fast stimulus-rise time and a fast and stable stimulus-onset time. We provide a detailed description of the olfactometer construction, a list of its individual parts and prices, as well as potential modifications to the design. In addition, we present odor onset and concentration curves as measured with a photoionization detector, together with corresponding GC/MS analyses of signal-intensity drop (5.9%) over a longer period of use. Finally, we present data from behavioral and psychophysiological recordings demonstrating that the olfactometer is suitable for use during event-related EEG experiments. PMID:20688109

  10. How much control is enough? Influence of unreliable input on user experience.

    PubMed

    van de Laar, Bram; Plass-Oude Bos, Danny; Reuderink, Boris; Poel, Mannes; Nijholt, Anton

    2013-12-01

    Brain–computer interfaces (BCI) provide a valuable new input modality within human–computer interaction systems. However, like other body-based inputs such as gesture or gaze based systems, the system recognition of input commands is still far from perfect. This raises important questions, such as what level of control should such an interface be able to provide. What is the relationship between actual and perceived control? And in the case of applications for entertainment in which fun is an important part of user experience, should we even aim for the highest level of control, or is the optimum elsewhere? In this paper, we evaluate whether we can modulate the amount of control and if a game can be fun with less than perfect control. In the experiment users (n = 158) played a simple game in which a hamster has to be guided to the exit of a maze. The amount of control the user has over the hamster is varied. The variation of control through confusion matrices makes it possible to simulate the experience of using a BCI, while using the traditional keyboard for input. After each session the user completed a short questionnaire on user experience and perceived control. Analysis of the data showed that the perceived control of the user could largely be explained by the amount of control in the respective session. As expected, user frustration decreases with increasing control. Moreover, the results indicate that the relation between fun and control is not linear. Although at lower levels of control fun does increase with improved control, the level of fun drops just before perfect control is reached (with an optimum around 96%). This poses new insights for developers of games who want to incorporate some form of BCI or other modality with unreliable input in their game: for creating a fun game, unreliable input can be used to create a challenge for the user.

  11. Notification: Notification Memo for Evaluation of Management Controls for Alternative Asbestos Control Method Experiments

    EPA Pesticide Factsheets

    Project #OPE-FY12-0011, February 27, 2012. This memorandum is to notify you that the Office of Inspector General (OIG) is initiating an evaluation on the Alternative Asbestos Control Method (AACM) experiments.

  12. Object-Based Control of Attention Is Sensitive to Recent Experience

    ERIC Educational Resources Information Center

    Lee, Hyunkyu; Mozer, Michael C.; Kramer, Arthur F.; Vecera, Shaun P.

    2012-01-01

    How is attention guided by past experience? In visual search, numerous studies have shown that recent trials influence responses to the current trial. Repeating features such as color, shape, or location of a target facilitates performance. Here we examine whether recent experience also modulates a more abstract dimension of attentional control,…

  13. Experience of Control and Student Satisfaction with Higher Education Services

    ERIC Educational Resources Information Center

    Lee, Jungki; Anantharaman, Sekhar

    2013-01-01

    Although the delivery of satisfactory services is an important strategic goal in many colleges, students are known to face challenges and experience a significant amount of stress during their school life. This study proposes and tests students' experience of control over their college life as a promising factor that would enhance their…

  14. Sexual Experience and Responses to a Birth Control Film.

    ERIC Educational Resources Information Center

    Herold, Edward S.; Thomas, Roger E.

    1980-01-01

    The relationship between sexual experience and contraceptive attitudinal responses to a birth control film is examined. Significant group differences were found regarding reinforcement of sexual attitudes but not for contraceptive attitudes. (JMF)

  15. F-16XL-2 Supersonic Laminar Flow Control Flight Test Experiment

    NASA Technical Reports Server (NTRS)

    Anders, Scott G.; Fischer, Michael C.

    1999-01-01

    The F-16XL-2 Supersonic Laminar Flow Control Flight Test Experiment was part of the NASA High-Speed Research Program. The goal of the experiment was to demonstrate extensive laminar flow, to validate computational fluid dynamics (CFD) codes and design methodology, and to establish laminar flow control design criteria. Topics include the flight test hardware and design, airplane modification, the pressure and suction distributions achieved, the laminar flow achieved, and the data analysis and code correlation.

  16. Control of Flexible Structures (COFS) Flight Experiment Background and Description

    NASA Technical Reports Server (NTRS)

    Hanks, B. R.

    1985-01-01

    A fundamental problem in designing and delivering large space structures to orbit is to provide sufficient structural stiffness and static configuration precision to meet performance requirements. These requirements are directly related to control requirements and the degree of control system sophistication available to supplement the as-built structure. Background and rationale are presented for a research study in structures, structural dynamics, and controls using a relatively large, flexible beam as a focus. This experiment would address fundamental problems applicable to large, flexible space structures in general and would involve a combination of ground tests, flight behavior prediction, and instrumented orbital tests. Intended to be multidisciplinary but basic within each discipline, the experiment should provide improved understanding and confidence in making design trades between structural conservatism and control system sophistication for meeting static shape and dynamic response/stability requirements. Quantitative results should be obtained for use in improving the validity of ground tests for verifying flight performance analyses.

  17. Remote Manipulator System (RMS)-based Controls-Structures Interaction (CSI) flight experiment feasibility study

    NASA Technical Reports Server (NTRS)

    Demeo, Martha E.

    1990-01-01

    The feasibility of an experiment which will provide an on-orbit validation of Controls-Structures Interaction (CSI) technology, was investigated. The experiment will demonstrate the on-orbit characterization and flexible-body control of large flexible structure dynamics using the shuttle Remote Manipulator System (RMS) with an attached payload as a test article. By utilizing existing hardware as well as establishing integration, operation and safety algorithms, techniques and procedures, the experiment will minimize the costs and risks of implementing a flight experiment. The experiment will also offer spin-off enhancement to both the Shuttle RMS (SRMS) and the Space Station RMS (SSRMS).

  18. Propulsion control experience used in the Highly Integrated Digital Electronic Control (HIDEC) program

    NASA Technical Reports Server (NTRS)

    Myers, L. P.; Burcham, F. W., Jr.

    1984-01-01

    The highly integrated digital electronic control (HIDEC) program will integrate the propulsion and flight control systems on an F-15 airplane at NASA Ames Research Center's Dryden Flight Research Facility. Ames-Dryden has conducted several propulsion control programs that have contributed to the HIDEC program. The digital electronic engine control (DEEC) flight evaluation investigated the performance and operability of the F100 engine equipped with a full-authority digital electronic control system. Investigations of nozzle instability, fault detection and accommodation, and augmentor transient capability provided important information for the HIDEC program. The F100 engine model derivative (EMD) was also flown in the F-15 airplane, and airplane performance was significantly improved. A throttle response problem was found and solved with a software fix to the control logic. For the HIDEC program, the F100 EMD engines equipped with DEEC controls will be integrated with the digital flight control system. The control modes to be implemented are an integrated flightpath management mode and an integrated adaptive engine control system mode. The engine control experience that will be used in the HIDEC program is discussed.

  19. 75 FR 24748 - Johnson Controls, Inc., Automotive Experience Division, Including Workers Whose Unemployment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-05

    ...., Automotive Experience Division, Including Workers Whose Unemployment Insurance (UI) Wages Are Paid Through... Assistance on October 6, 2009, applicable to workers of Johnson Controls, Inc., Automotive Experience... industry. New information shows that Johnson Controls purchased Hoover Universal in 1985 and that some...

  20. Baseline experiments in teleoperator control

    NASA Technical Reports Server (NTRS)

    Hankins, W. W., III; Mixon, R. W.

    1986-01-01

    Studies have been conducted at the NASA Langley Research Center (LaRC) to establish baseline human teleoperator interface data and to assess the influence of some of the interface parameters on human performance in teleoperation. As baseline data, the results will be used to assess future interface improvements resulting from this research in basic teleoperator human factors. In addition, the data have been used to validate LaRC's basic teleoperator hardware setup and to compare initial teleoperator study results. Four subjects controlled a modified industrial manipulator to perform a simple task involving both high and low precision. Two different schemes for controlling the manipulator were studied along with both direct and indirect viewing of the task. Performance of the task was measured as the length of time required to complete the task along with the number of errors made in the process. Analyses of variance were computed to determine the significance of the influences of each of the independent variables. Comparisons were also made between the LaRC data and data taken earlier by Grumman Aerospace Corp. at their facilities.

  1. Management Control Systems and Clinical Experience of Managers in Public Hospitals.

    PubMed

    Lunkes, Rogério Joao; Naranjo-Gil, David; Lopez-Valeiras, Ernesto

    2018-04-17

    Healthcare authorities are encouraging managers in hospitals to acquire clinical experience and knowledge in order to better carry out and coordinate healthcare service delivery. The main objective of this paper is to analyse how the clinical experience of hospital managers is related to public health institutions’ performance. It is proposed that the effect of the clinical experience on operative and financial organizational performance is indirect through the mediating variables of perceived utility of management information and horizontal management control system. This paper analyses how these variables impact hospital performance through the data from a survey sent to 364 hospital managers in Brazil. The results show that managers’ clinical experience is related to higher perceived utility of historical, financial, short-term, and internal information, but not with horizontal control adoption in hospitals. Furthermore, our results show that, in hospitals, perceived utility of forecasted, non-financial, long-term, and external managerial information positively affects hospitals’ financial performance, while adoption of horizontal control management positively affects operational performance. Through showing evidence that clinical background could explain the differences not only in hospital service management but also in information capabilities and management control processes, this study offer meaningful implications for healthcare authorities and hospital managers involved in the development and implementation of strategies in the health sector.

  2. Seagrass metabolism across a productivity gradient using the eddy covariance, Eulerian control volume, and biomass addition techniques

    NASA Astrophysics Data System (ADS)

    Long, Matthew H.; Berg, Peter; Falter, James L.

    2015-05-01

    The net ecosystem metabolism of the seagrass Thalassia testudinum was studied across a nutrient and productivity gradient in Florida Bay, Florida, using the Eulerian control volume, eddy covariance, and biomass addition techniques. In situ oxygen fluxes were determined by a triangular Eulerian control volume with sides 250 m long and by eddy covariance instrumentation at its center. The biomass addition technique evaluated the aboveground seagrass productivity through the net biomass added. The spatial and temporal resolutions, accuracies, and applicability of each method were compared. The eddy covariance technique better resolved the short-term flux rates and the productivity gradient across the bay, which was consistent with the long-term measurements from the biomass addition technique. The net primary production rates from the biomass addition technique, which were expected to show greater autotrophy due to the exclusion of sediment metabolism and belowground production, were 71, 53, and 30 mmol carbon m-2 d-1 at 3 sites across the bay. The net ecosystem metabolism was 35, 25, and 11 mmol oxygen m-2 d-1 from the eddy covariance technique and 10, -103, and 14 mmol oxygen m-2 d-1 from the Eulerian control volume across the same sites, respectively. The low-flow conditions in the shallow bays allowed for periodic stratification and long residence times within the Eulerian control volume that likely reduced its precision. Overall, the eddy covariance technique had the highest temporal resolution while producing accurate long-term flux rates that surpassed the capabilities of the biomass addition and Eulerian control volume techniques in these shallow coastal bays.

  3. Hierarchical tailoring of strut architecture to control permeability of additive manufactured titanium implants.

    PubMed

    Zhang, Z; Jones, D; Yue, S; Lee, P D; Jones, J R; Sutcliffe, C J; Jones, E

    2013-10-01

    Porous titanium implants are a common choice for bone augmentation. Implants for spinal fusion and repair of non-union fractures must encourage blood flow after implantation so that there is sufficient cell migration, nutrient and growth factor transport to stimulate bone ingrowth. Additive manufacturing techniques allow a large number of pore network designs. This study investigates how the design factors offered by selective laser melting technique can be used to alter the implant architecture on multiple length scales to control and even tailor the flow. Permeability is a convenient parameter that characterises flow, correlating to structure openness (interconnectivity and pore window size), tortuosity and hence flow shear rates. Using experimentally validated computational simulations, we demonstrate how additive manufacturing can be used to tailor implant properties by controlling surface roughness at a microstructual level (microns), and by altering the strut ordering and density at a mesoscopic level (millimetre). Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  4. Recent experience in simultaneous control-structure optimization

    NASA Technical Reports Server (NTRS)

    Salama, M.; Ramaker, R.; Milman, M.

    1989-01-01

    To show the feasibility of simultaneous optimization as design procedure, low order problems were used in conjunction with simple control formulations. The numerical results indicate that simultaneous optimization is not only feasible, but also advantageous. Such advantages come at the expense of introducing complexities beyond those encountered in structure optimization alone, or control optimization alone. Examples include: larger design parameter space, optimization may combine continuous and combinatoric variables, and the combined objective function may be nonconvex. Future extensions to include large order problems, more complex objective functions and constraints, and more sophisticated control formulations will require further research to ensure that the additional complexities do not outweigh the advantages of simultaneous optimization. Some areas requiring more efficient tools than currently available include: multiobjective criteria and nonconvex optimization. Efficient techniques to deal with optimization over combinatoric and continuous variables, and with truncation issues for structure and control parameters of both the model space as well as the design space need to be developed.

  5. Stochastic sampled-data control for synchronization of complex dynamical networks with control packet loss and additive time-varying delays.

    PubMed

    Rakkiyappan, R; Sakthivel, N; Cao, Jinde

    2015-06-01

    This study examines the exponential synchronization of complex dynamical networks with control packet loss and additive time-varying delays. Additionally, sampled-data controller with time-varying sampling period is considered and is assumed to switch between m different values in a random way with given probability. Then, a novel Lyapunov-Krasovskii functional (LKF) with triple integral terms is constructed and by using Jensen's inequality and reciprocally convex approach, sufficient conditions under which the dynamical network is exponentially mean-square stable are derived. When applying Jensen's inequality to partition double integral terms in the derivation of linear matrix inequality (LMI) conditions, a new kind of linear combination of positive functions weighted by the inverses of squared convex parameters appears. In order to handle such a combination, an effective method is introduced by extending the lower bound lemma. To design the sampled-data controller, the synchronization error system is represented as a switched system. Based on the derived LMI conditions and average dwell-time method, sufficient conditions for the synchronization of switched error system are derived in terms of LMIs. Finally, numerical example is employed to show the effectiveness of the proposed methods. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Shuttle Payload Ground Command and Control: An Experiment Implementation Combustion Module-2 Software Development, STS-107

    NASA Technical Reports Server (NTRS)

    Carek, David Andrew

    2003-01-01

    This presentation covers the design of a command and control architecture developed by the author for the Combustion Module-2 microgravity experiment, which flew aboard the STS-107 Shuttle mission, The design was implemented to satisfy a hybrid network that utilized TCP/IP for both the onboard segment and ground segment, with an intermediary unreliable transport for the space to ground segment. With the infusion of Internet networking technologies into Space Shuttle, Space Station, and spacecraft avionics systems, comes the need for robust methodologies for ground command and control. Considerations of high bit error links, and unreliable transport over intermittent links must be considered in such systems. Internet protocols applied to these systems, coupled with the appropriate application layer protections, can provide adequate communication architectures for command and control. However, there are inherent limitations and additional complexities added by the use of Internet protocols that must be considered during the design. This presentation will discuss the rationale for the: framework and protocol algorithms developed by the author. A summary of design considerations, implantation issues, and learned lessons will be will be presented. A summary of mission results using this communications architecture will be presented. Additionally, areas of further needed investigation will be identified.

  7. A placebo-controlled investigation of synaesthesia-like experiences under LSD.

    PubMed

    Terhune, Devin B; Luke, David P; Kaelen, Mendel; Bolstridge, Mark; Feilding, Amanda; Nutt, David; Carhart-Harris, Robin; Ward, Jamie

    2016-07-29

    The induction of synaesthesia in non-synaesthetes has the potential to illuminate the mechanisms that contribute to the development of this condition and the shaping of its phenomenology. Previous research suggests that lysergic acid diethylamide (LSD) reliably induces synaesthesia-like experiences in non-synaesthetes. However, these studies suffer from a number of methodological limitations including lack of a placebo control and the absence of rigorous measures used to test established criteria for genuine synaesthesia. Here we report a pilot study that aimed to circumvent these limitations. We conducted a within-groups placebo-controlled investigation of the impact of LSD on colour experiences in response to standardized graphemes and sounds and the consistency and specificity of grapheme- and sound-colour associations. Participants reported more spontaneous synaesthesia-like experiences under LSD, relative to placebo, but did not differ across conditions in colour experiences in response to inducers, consistency of stimulus-colour associations, or in inducer specificity. Further analyses suggest that individual differences in a number of these effects were associated with the propensity to experience states of absorption in one's daily life. Although preliminary, the present study suggests that LSD-induced synaesthesia-like experiences do not exhibit consistency or inducer-specificity and thus do not meet two widely established criteria for genuine synaesthesia. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Attributional Biases in Psychiatric Patients, a Religious, and a Control Group in the Assessment of a Hallucinatory Experience: The "White Christmas Test".

    PubMed

    Parra, Alejandro; Maschi, Gianina

    The aim of this study was to evaluate the auditory hallucinatory experience in a clinical sample of patients with psychiatric symptoms (e.g. Schizophrenia), a religious group (eg. Christians) and a "control" group (with no mental disorder and non-religious). The sample consisted of individuals of both sexes. The patient sample was recruited in two psychiatric hospitals of Buenos Aires City, the religious from an evangelical cult, and people with no religious beliefs or previous psychiatric symptoms (control group). The Hallucinatory Experiences Questionnaire and the Oxford-Liverpool Inventory Feelings and Experiences were the measurement tools used. The White Christmas Test was also administered in order to assess the degree of vivid imagery hearing based on a version of signal detection paradigm in which the subjects think that they hear a song in the background of white noise. The results showed that patients showed greater attributional bias (compared with evangelicals and the control group), but the religious group also tended to show greater bias (although less) than the control group. In addition, patients tended to show greater schizotypal and hallucinatory experiences compared with the evangelicals and the control group, but surprisingly, the control group showed higher negative schizotypy than the religious group, which indicates that religious practices could help reduce the negative effects of schizotypy. Copyright © 2017 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  9. Full-scale evaluation of a multi-component additive for efficient control of activated sludge filamentous bulking.

    PubMed

    Seka, M A; Van DeWiele, T; Verstraete, W

    2002-01-01

    A multi-component additive formulated for a more efficient control of activated sludge filamentous bulking was evaluated at a full-scale treatment plant experiencing severe filamentous bulking. It was found that, besides offering an immediate improvement of sludge settling, the multi-component additive was able to eliminate the filamentous bacteria causing the bulking. Hence, contrary to ordinary additives, this novel additive yielded immediate as well as long-term improvements in sludge sedimentation upon a few additions. Preliminary lab-scale toxicity tests showed that the treatment of the sludge by the additive should not impart any toxicity to the resulting effluent.

  10. Insights Into Atmospheric Aqueous Organic Chemistry Through Controlled Experiments with Cloud Water Surrogates

    NASA Astrophysics Data System (ADS)

    Turpin, B. J.; Ramos, A.; Kirkland, J. R.; Lim, Y. B.; Seitzinger, S.

    2011-12-01

    There is considerable laboratory and field-based evidence that chemical processing in clouds and wet aerosols alters organic composition and contributes to the formation of secondary organic aerosol (SOA). Single-compound laboratory experiments have played an important role in developing aqueous-phase chemical mechanisms that aid prediction of SOA formation through multiphase chemistry. In this work we conduct similar experiments with cloud/fog water surrogates, to 1) evaluate to what extent the previously studied chemistry is observed in these more realistic atmospheric waters, and 2) to identify additional atmospherically-relevant precursors and products that require further study. We used filtered Camden and Pinelands, NJ rainwater as a surrogate for cloud water. OH radical (~10-12 M) was formed by photolysis of hydrogen peroxide and samples were analyzed in real-time by electrospray ionization mass spectroscopy (ESI-MS). Discrete samples were also analyzed by ion chromatography (IC) and ESI-MS after IC separation. All experiments were performed in duplicate. Standards of glyoxal, methylglyoxal and glycolaldehyde and their major aqueous oxidation products were also analyzed, and control experiments performed. Decreases in the ion abundance of many positive mode compounds and increases in the ion abundance of many negative mode compounds (e.g., organic acids) suggest that precursors are predominantly aldehydes, organic peroxides and/or alcohols. Real-time ESI mass spectra were consistent with the expected loss of methylglyoxal and subsequent formation of pyruvate, glyoxylate, and oxalate. New insights regarding other potential precursors and products will be provided.

  11. A survey of experiments and experimental facilities for control of flexible structures

    NASA Technical Reports Server (NTRS)

    Sparks, Dean W., Jr.; Juang, Jer-Nan; Klose, Gerhard J.

    1989-01-01

    This paper presents a survey of U.S. ground experiments and facilities dedicated to the study of active control of flexible structures. The facilities will be briefly described in terms of capability, configuration, size and instrumentation. Topics on the experiments include vibration suppression, slewing and system identification. Future research directions, particularly of the NASA Langley Research Center's Controls/Structures Interaction (CSI) ground test program, will be discussed.

  12. Slew maneuvers of Spacecraft Control Laboratory Experiment (SCOLE)

    NASA Technical Reports Server (NTRS)

    Kakad, Yogendra P.

    1992-01-01

    This is the final report on the dynamics and control of slew maneuvers of the Spacecraft Control Laboratory Experiment (SCOLE) test facility. The report documents the basic dynamical equation derivations for an arbitrary large angle slew maneuver as well as the basic decentralized slew maneuver control algorithm. The set of dynamical equations incorporate rigid body slew maneuver and three dimensional vibrations of the complete assembly comprising the rigid shuttle, the flexible beam, and the reflector with an offset mass. The analysis also includes kinematic nonlinearities of the entire assembly during the maneuver and the dynamics of the interactions between the rigid shuttle and the flexible appendage. The equations are simplified and evaluated numerically to include the first ten flexible modes to yield a model for designing control systems to perform slew maneuvers. The control problem incorporates the nonlinear dynamical equations and is expressed in terms of a two point boundary value problem.

  13. A Process Dynamics and Control Experiment for the Undergraduate Laboratory

    ERIC Educational Resources Information Center

    Spencer, Jordan L.

    2009-01-01

    This paper describes a process control experiment. The apparatus includes a three-vessel glass flow system with a variable flow configuration, means for feeding dye solution controlled by a stepper-motor driven valve, and a flow spectrophotometer. Students use impulse response data and nonlinear regression to estimate three parameters of a model…

  14. Coherent operation of detector systems and their readout electronics in a complex experiment control environment

    NASA Astrophysics Data System (ADS)

    Koestner, Stefan

    2009-09-01

    With the increasing size and degree of complexity of today's experiments in high energy physics the required amount of work and complexity to integrate a complete subdetector into an experiment control system is often underestimated. We report here on the layered software structure and protocols used by the LHCb experiment to control its detectors and readout boards. The experiment control system of LHCb is based on the commercial SCADA system PVSS II. Readout boards which are outside the radiation area are accessed via embedded credit card sized PCs which are connected to a large local area network. The SPECS protocol is used for control of the front end electronics. Finite state machines are introduced to facilitate the control of a large number of electronic devices and to model the whole experiment at the level of an expert system.

  15. Effect of an Immersive Preoperative Virtual Reality Experience on Patient Reported Outcomes: A Randomized Controlled Trial.

    PubMed

    Bekelis, Kimon; Calnan, Daniel; Simmons, Nathan; MacKenzie, Todd A; Kakoulides, George

    2017-06-01

    To investigate the effect of exposure to a virtual reality (VR) environment preoperatively on patient-reported outcomes for surgical operations. There is a scarcity of well-developed quality improvement initiatives targeting patient satisfaction. We performed a randomized controlled trial of patients undergoing cranial and spinal operations in a tertiary referral center. Patients underwent a 1:1 randomization to an immersive preoperative VR experience or standard preoperative experience stratified on type of operation. The primary outcome measures were the Evaluation du Vecu de l'Anesthesie Generale (EVAN-G) score and the Amsterdam Preoperative Anxiety and Information (APAIS) score, as markers of the patient's experience during the surgical encounter. During the study period, a total of 127 patients (mean age 55.3 years, 41.9% females) underwent randomization. The average EVAN-G score was 84.3 (standard deviation, SD, 6.4) after VR, and 64.3 (SD, 11.7) after standard preoperative experience (difference, 20.0; 95% confidence interval, CI, 16.6-23.3). Exposure to an immersive VR experience also led to higher APAIS score (difference, 29.9; 95% CI, 24.5-35.2). In addition, VR led to lower preoperative VAS stress score (difference, -41.7; 95% CI, -33.1 to -50.2), and higher preoperative VAS preparedness (difference, 32.4; 95% CI, 24.9-39.8), and VAS satisfaction (difference, 33.2; 95% CI, 25.4-41.0) scores. No association was identified with VAS stress score (difference, -1.6; 95% CI, -13.4 to 10.2). In a randomized controlled trial, we demonstrated that patients exposed to preoperative VR had increased satisfaction during the surgical encounter. Harnessing the power of this technology, hospitals can create an immersive environment that minimizes stress, and enhances the perioperative experience.

  16. Enhancing Schistosomiasis Control Strategy for Zimbabwe: Building on Past Experiences

    PubMed Central

    Chimbari, Moses J.

    2012-01-01

    Schistosoma haematobium and Schistosoma mansoni are prevalent in Zimbabwe to levels that make schistosomiasis a public health problem. Following three national surveys to map the disease prevalence, a national policy on control of schistosomiasis and soil transmitted helminths is being developed. This paper reviews the experiences that Zimbabwe has in the area of schistosomiasis control with a view to influence policy. A case study approach to highlight key experiences and outcomes was adopted. The benefits derived from intersectoral collaboration that led to the development of a model irrigation scheme that incorporates schistosomiasis control measures are highlighted. Similarly, the benefits of using plant molluscicides and fish and duck biological agents (Sargochromis codringtonii and Cairina moschata) are highlighted. Emphasis was also placed on the importance of utilizing locally developed water and sanitation technologies and the critical human resource base in the area of schistosomiasis developed over years. After synthesis of the case studies presented, it was concluded that while there is a need to follow the WHO recommended guidelines for schistosomiasis control it is important to develop a control strategy that is informed by work already done in the country. The importance of having a policy and local guidelines for schistosomiasis control is emphasized. PMID:22655171

  17. Analysis of Latest Experience in Design of Industrial Buildings Reconstruction by Constructing Additional Interfloor Overlaps

    NASA Astrophysics Data System (ADS)

    Peshnina, I.; Sinitsina, O.

    2017-11-01

    The study relevance is determined by the increasing interest in reconstruction of city historical centers and located in the area of industrial buildings the functional profile of which needs to be changed. The problem of obtaining extra usable spaces in the historical centers of cities is solved by raising the number of storeys in the buildings which can be achieved by the construction of additional built-in inter-floor overlaps. The article is dedicated to the analysis of the recent years’ experience in reconstruction design involving this method in our country and abroad, in the Netherlands, in particular. The article presents the results of the analysis of the experience in reconstruction of the objects by constructing additional inter-floor overlaps and aims to define the optimum construction solution for built-in inter-floor overlapping and to develop non-existing solutions for wide application of this method in the reconstruction of a building with non-unified and unmodulated parameters. It was determined as expedient to apply a monolith reinforced concrete slab with the use of steel profiled flooring as a formwork and reinforcement and steel beams designed as “Built-in Beams” for the construction of built-in inter-floor overlaps in reconstruction. The article will be useful for specialists doing research in the sphere of reconstruction of the buildings and for the practical activity of design engineers.

  18. Assessing Prior Experience in the Selection of Air Traffic Control Specialists

    DTIC Science & Technology

    2013-04-01

    Crosstabulation --------------------------B1 APPENDIX C: IFR Operations Experience • Academy Training Performance Crosstabulation ---------C1 APPENDIX...Control Specialist (ATCS) rating? (n=9,333) BQ35 – Do you have prior Instrument Flight Rules ( IFR ) operations experience? (n = 9,349) 2. Hold or...not have a prior ATCS rating. Do you have prior IFR (Instrument Flight Rules) Operations experience? Of the 9,349 respondents to this question

  19. A survey of experiments and experimental facilities for active control of flexible structures

    NASA Technical Reports Server (NTRS)

    Sparks, Dean W., Jr.; Horner, Garnett C.; Juang, Jer-Nan; Klose, Gerhard

    1989-01-01

    A brief survey of large space structure control related experiments and facilities was presented. This survey covered experiments performed before and up to 1982, and those of the present period (1982-...). Finally, the future planned experiments and facilities in support of the control-structure interaction (CSI) program were reported. It was stated that new, improved ground test facilities are needed to verify the new CSI design techniques that will allow future space structures to perform planned NASA missions.

  20. Maximization of DRAM yield by control of surface charge and particle addition during high dose implantation

    NASA Astrophysics Data System (ADS)

    Horvath, J.; Moffatt, S.

    1991-04-01

    Ion implantation processing exposes semiconductor devices to an energetic ion beam in order to deposit dopant ions in shallow layers. In addition to this primary process, foreign materials are deposited as particles and surface films. The deposition of particles is a major cause of IC yield loss and becomes even more significant as device dimensions are decreased. Control of particle addition in a high-volume production environment requires procedures to limit beamline and endstation sources, control of particle transport, cleaning procedures and a well grounded preventative maintenance philosophy. Control of surface charge by optimization of the ion beam and electron shower conditions and measurement with a real-time charge sensor has been effective in improving the yield of NMOS and CMOS DRAMs. Control of surface voltages to a range between 0 and -20 V was correlated with good implant yield with PI9200 implanters for p + and n + source-drain implants.

  1. Experiments in Aircraft Roll-Yaw Control using Forebody Tangential Blowing

    NASA Technical Reports Server (NTRS)

    Pedreiro, Nelson

    1997-01-01

    Advantages of flight at high angles of attack include increased maneuverability and lift capabilities. These are beneficial not only for fighter aircraft, but also for future supersonic and hypersonic transport aircraft during take-off and landing. At high angles of attack the aerodynamics of the vehicle are dominated by separation, vortex shedding and possibly vortex breakdown. These phenomena severely compromise the effectiveness of conventional control surfaces. As a result, controlled flight at high angles of attack is not feasible for current aircraft configurations. Alternate means to augment the control of the vehicle at these flight regimes are therefore necessary. The present work investigates the augmentation of an aircraft flight control system by the injection of a thin sheet of air tangentially to the forebody of the vehicle. This method, known as Forebody Tangential Blowing (FTB), has been proposed as an effective means of increasing the controllability of aircraft at high angles of attack. The idea is based on the fact that a small amount of air is sufficient to change the separation lines on the forebody. As a consequence, the strength and position of the vortices are altered causing a change on the aerodynamic loads. Although a very effective actuator, forebody tangential blowing is also highly non-linear which makes its use for aircraft control very difficult. In this work, the feasibility of using FTB to control the roll-yaw motion of a wind tunnel model was demonstrated both through simulations and experimentally. The wind tunnel model used in the experiments consists of a wing-body configuration incorporating a delta wing with 70-degree sweep angle and a cone-cylinder fuselage. The model is equipped with forebody slots through which blowing is applied. There are no movable control surfaces, therefore blowing is the only form of actuation. Experiments were conducted at a nominal angle of attack of 45 degrees. A unique apparatus that constrains

  2. The dilemma of allergy to food additives.

    PubMed

    Bahna, Sami L; Burkhardt, Joshua G

    2018-01-01

    To provide a brief summary on food additives and to outline a practical approach for evaluating subjects suspected of having reactions to food additives. Information was derived from selected reviews and original articles published in peer-reviewed journals, supplemented by the clinical experience of the authors. Priority was given to studies that used blinded, placebo controlled, oral challenges to confirm adverse reactions to food additives. In addition, selected, appropriately evaluated case reports were included. A large number of food additives are widely used in the food industry. Allergic reactions to additives seem to be rare but are very likely underdiagnosed, primarily due to a low index of suspicion. A wide variety of symptoms to food additives have been reported, but a cause-and-effect relationship has not been well documented in the majority of cases. Reactions to food additives should be suspected in patients who report symptoms related to multiple foods or to a certain food when commercially prepared but not when home made. It is also prudent to investigate food additives in subjects considered to have "idiopathic" reactions. Except for a limited number of natural additives, there is a small role for skin tests or in vitro testing. Oral challenge, in stages, with commonly used additives is the definitive procedure for detecting the offending agent. Once the specific additive is identified, management is strict avoidance, which can be difficult.

  3. Tank Pressure Control Experiment: Thermal Phenomena in Microgravity

    NASA Technical Reports Server (NTRS)

    Hasan, Mohammad M.; Lin, Chin S.; Knoll, Richard H.; Bentz, Michael D.

    1996-01-01

    The report presents the results of the flight experiment Tank Pressure Control Experiment/Thermal Phenomena (TPCE/TP) performed in the microgravity environment of the space shuttle. TPCE/TP, flown on the Space Transportation System STS-52, was a second flight of the Tank Pressure Control Experiment (TPCE). The experiment used Freon 113 at near saturation conditions. The test tank was filled with liquid to about 83% by volume. The experiment consisted of 21 tests. Each test generally started with a heating phase to increase the tank pressure and to develop temperature stratification in the fluid, followed by a fluid mixing phase for the tank pressure reduction and fluid temperature equilibration. The heating phase provided pool boiling data from large (relative to bubble sizes) heating surfaces (0.1046 m by 0.0742 m) at low heat fluxes (0.23 to 1.16 kW/sq m). The system pressure and the bulk liquid subcooling varied from 39 to 78 kPa and 1 to 3 C, respectively. The boiling process during the entire heating period, as well as the jet-induced mixing process for the first 2 min of the mixing period, was also recorded on video. The unique features of the experimental results are the sustainability of high liquid superheats for long periods and the occurrence of explosive boiling at low heat fluxes (0.86 to 1.1 kW/sq m). For a heat flux of 0.97 kW/sq m, a wall superheat of 17.9 C was attained in 10 min of heating. This superheat was followed by an explosive boiling accompanied by a pressure spike of about 38% of the tank pressure at the inception of boiling. However, at this heat flux the vapor blanketing the heating surface could not be sustained. Steady nucleate boiling continued after the explosive boiling. The jet-induced fluid mixing results were obtained for jet Reynolds numbers of 1900 to 8000 and Weber numbers of 0.2 to 6.5. Analyses of data from the two flight experiments (TPCE and TPCE/TP) and their comparison with the results obtained in drop tower experiments

  4. The Intelligent Control System and Experiments for an Unmanned Wave Glider.

    PubMed

    Liao, Yulei; Wang, Leifeng; Li, Yiming; Li, Ye; Jiang, Quanquan

    2016-01-01

    The control system designing of Unmanned Wave Glider (UWG) is challenging since the control system is weak maneuvering, large time-lag and large disturbance, which is difficult to establish accurate mathematical model. Meanwhile, to complete marine environment monitoring in long time scale and large spatial scale autonomously, UWG asks high requirements of intelligence and reliability. This paper focuses on the "Ocean Rambler" UWG. First, the intelligent control system architecture is designed based on the cerebrum basic function combination zone theory and hierarchic control method. The hardware and software designing of the embedded motion control system are mainly discussed. A motion control system based on rational behavior model of four layers is proposed. Then, combining with the line-of sight method(LOS), a self-adapting PID guidance law is proposed to compensate the steady state error in path following of UWG caused by marine environment disturbance especially current. Based on S-surface control method, an improved S-surface heading controller is proposed to solve the heading control problem of the weak maneuvering carrier under large disturbance. Finally, the simulation experiments were carried out and the UWG completed autonomous path following and marine environment monitoring in sea trials. The simulation experiments and sea trial results prove that the proposed intelligent control system, guidance law, controller have favorable control performance, and the feasibility and reliability of the designed intelligent control system of UWG are verified.

  5. The Intelligent Control System and Experiments for an Unmanned Wave Glider

    PubMed Central

    Liao, Yulei; Wang, Leifeng; Li, Yiming; Li, Ye; Jiang, Quanquan

    2016-01-01

    The control system designing of Unmanned Wave Glider (UWG) is challenging since the control system is weak maneuvering, large time-lag and large disturbance, which is difficult to establish accurate mathematical model. Meanwhile, to complete marine environment monitoring in long time scale and large spatial scale autonomously, UWG asks high requirements of intelligence and reliability. This paper focuses on the “Ocean Rambler” UWG. First, the intelligent control system architecture is designed based on the cerebrum basic function combination zone theory and hierarchic control method. The hardware and software designing of the embedded motion control system are mainly discussed. A motion control system based on rational behavior model of four layers is proposed. Then, combining with the line-of sight method(LOS), a self-adapting PID guidance law is proposed to compensate the steady state error in path following of UWG caused by marine environment disturbance especially current. Based on S-surface control method, an improved S-surface heading controller is proposed to solve the heading control problem of the weak maneuvering carrier under large disturbance. Finally, the simulation experiments were carried out and the UWG completed autonomous path following and marine environment monitoring in sea trials. The simulation experiments and sea trial results prove that the proposed intelligent control system, guidance law, controller have favorable control performance, and the feasibility and reliability of the designed intelligent control system of UWG are verified. PMID:28005956

  6. Antenatal hypnosis training and childbirth experience: a randomized controlled trial.

    PubMed

    Werner, Anette; Uldbjerg, Niels; Zachariae, Robert; Wu, Chun Sen; Nohr, Ellen A

    2013-12-01

    Childbirth is a demanding event in a woman's life. The aim of this study was to explore whether a brief intervention in the form of an antenatal course in self-hypnosis to ease childbirth could improve the childbirth experience. In a randomized, controlled, single-blinded trial, 1,222 healthy nulliparous women were allocated to one of three groups during pregnancy: A hypnosis group participating in three 1-hour sessions teaching self-hypnosis to ease childbirth, a relaxation group receiving three 1-hour lessons in various relaxation methods and Mindfulness, and a usual care group receiving ordinary antenatal care only. Wijmas Delivery Expectancy/Experience Questionnaire (W-DEQ) was used to measure the childbirth experience 6 weeks postpartum. The intention-to-treat analysis indicated that women in the hypnosis group experienced their childbirth as better compared with the other two groups (mean W-DEQ score of 42.9 in the Hypnosis group, 47.2 in the Relaxation group, and 47.5 in the Care as usual group (p = 0.01)). The tendency toward a better childbirth experience in the hypnosis group was also seen in subgroup analyses for mode of delivery and for levels of fear. In this large randomized controlled trial, a brief course in self-hypnosis improved the women's childbirth experience. © 2013, Copyright the Authors Journal compilation © 2013, Wiley Periodicals, Inc.

  7. Soldier experiments and assessments using SPEAR speech control system for UGVs

    NASA Astrophysics Data System (ADS)

    Brown, Jonathan; Blanco, Chris; Czerniak, Jeffrey; Hoffman, Brian; Hoffman, Orin; Juneja, Amit; Ngia, Lester; Pruthi, Tarun; Liu, Dongqing

    2010-04-01

    This paper reports on a Soldier Experiment performed by the Army Research Lab's Human Research Engineering Directorate (HRED) Field Element located at the Maneuver Center of Excellence, Ft. Benning, and a Limited Use Assessment conducted by the Marine Corps Forces Pacific Command Experimentation Center (MEC) at Camp Pendleton evaluating the effectiveness of using speech commands to control an Unmanned Ground Vehicle. SPEAR, developed by Think-A-Move, Ltd., provides speech control of UGVs. SPEAR detects user speech in the ear canal with an earpiece containing an in-ear microphone. The system design provides up to 30 dB of passive noise reduction, enabling it to work well in high-noise environments, where traditional speech systems, using external microphones, fail; it also utilizes a proprietary speech recognition engine. SPEAR has been integrated with iRobot's PackBot 510 with FasTac Kit, and with Multi-Robot Operator Control Unit (MOCU), developed by SPAWAR Systems Center Pacific. These integrated systems allow speech to supplement the hand-controller for multi-modal control of different UGV functions simultaneously. HRED's experiment measured the impact of SPEAR on reducing the cognitive load placed on UGV Operators and the time to complete specific tasks. Army NCOs and Officer School Candidates participated in this experiment, which found that speech control was faster than manual control to complete tasks requiring menu navigation, as well as reducing the cognitive load on UGV Operators. The MEC assessment examined speech commands used for two different missions: Route Clearance and Cordon and Search; participants included Explosive Ordnance Disposal Technicians and Combat Engineers. The majority of the Marines thought it was easier to complete the mission scenarios with SPEAR than with only using manual controls, and that using SPEAR improved their situational awareness. Overall results of these Assessments are reported in the paper, along with possible

  8. Assessing Subjectivity in Sensor Data Post Processing via a Controlled Experiment

    NASA Astrophysics Data System (ADS)

    Jones, A. S.; Horsburgh, J. S.; Eiriksson, D.

    2017-12-01

    Environmental data collected by in situ sensors must be reviewed to verify validity, and conducting quality control often requires making edits in post processing to generate approved datasets. This process involves decisions by technicians, data managers, or data users on how to handle problematic data. Options include: removing data from a series, retaining data with annotations, and altering data based on algorithms related to adjacent data points or the patterns of data at other locations or of other variables. Ideally, given the same dataset and the same quality control guidelines, multiple data quality control technicians would make the same decisions in data post processing. However, despite the development and implementation of guidelines aimed to ensure consistent quality control procedures, we have faced ambiguity when performing post processing, and we have noticed inconsistencies in the practices of individuals performing quality control post processing. Technicians with the same level of training and using the same input datasets may produce different results, affecting the overall quality and comparability of finished data products. Different results may also be produced by technicians that do not have the same level of training. In order to assess the effect of subjective decision making by the individual technician on the end data product, we designed an experiment where multiple users performed quality control post processing on the same datasets using a consistent set of guidelines, field notes, and tools. We also assessed the effect of technician experience and training by conducting the same procedures with a group of novices unfamiliar with the data and the quality control process and compared their results to those generated by a group of more experienced technicians. In this presentation, we report our observations of the degree of subjectivity in sensor data post processing, assessing and quantifying the impacts of individual technician as

  9. An Experiment of GMPLS-Based Dispersion Compensation Control over In-Field Fibers

    NASA Astrophysics Data System (ADS)

    Seno, Shoichiro; Horiuchi, Eiichi; Yoshida, Sota; Sugihara, Takashi; Onohara, Kiyoshi; Kamei, Misato; Baba, Yoshimasa; Kubo, Kazuo; Mizuochi, Takashi

    As ROADMs (Reconfigurable Optical Add/Drop Multiplexers) are becoming widely used in metro/core networks, distributed control of wavelength paths by extended GMPLS (Generalized MultiProtocol Label Switching) protocols has attracted much attention. For the automatic establishment of an arbitrary wavelength path satisfying dynamic traffic demands over a ROADM or WXC (Wavelength Cross Connect)-based network, precise determination of chromatic dispersion over the path and optimized assignment of dispersion compensation capabilities at related nodes are essential. This paper reports an experiment over in-field fibers where GMPLS-based control was applied for the automatic discovery of chromatic dispersion, path computation, and wavelength path establishment with dynamic adjustment of variable dispersion compensation. The GMPLS-based control scheme, which the authors called GMPLS-Plus, extended GMPLS's distributed control architecture with attributes for automatic discovery, advertisement, and signaling of chromatic dispersion. In this experiment, wavelength paths with distances of 24km and 360km were successfully established and error-free data transmission was verified. The experiment also confirmed path restoration with dynamic compensation adjustment upon fiber failure.

  10. In-field experiment of electro-hydraulic tillage depth draft-position mixed control on tractor

    NASA Astrophysics Data System (ADS)

    Han, Jiangyi; Xia, Changgao; Shang, Gaogao; Gao, Xiang

    2017-12-01

    The soil condition and condition of the plow affect the tillage resistance and the maximum traction of tractor. In order to improve the adaptability of tractor tillage depth control, a multi-parameter control strategy is proposed that included tillage depth target, draft force aim and draft-position mixed ratio. In the strategy, the resistance coefficient was used to adjust the draft force target. Then, based on a JINMA1204 tractor, the electro-hydraulic hitch prototype is constructed that could set control parameters.. The fuzzy controller of draft-position mixed control is designed. After that, in-field experiments of position control was carried on, and the result of experiment shows the error of tillage depth was less than ±20mm. The experiment of draft-position control shown that the draft force and the tillage depth could be adjust by multi-parameter such as tillage depth, resistance coefficient and draft-position mixed coefficient. So that, the multi-parameter control strategy could improve the adaptability of tillage depth control in various soils and plow condition.

  11. How to build institutionalization on students: a pilot experiment on a didactical design of addition and subtraction involving negative integers

    NASA Astrophysics Data System (ADS)

    Fuadiah, N. F.; Suryadi, D.; Turmudi

    2018-05-01

    This study focuses on the design of a didactical situation in addition and subtraction involving negative integers at the pilot experiment phase. As we know, negative numbers become an obstacle for students in solving problems related to them. This study aims to create a didactical design that can assist students in understanding the addition and subtraction. Another expected result in this way is that students are introduced to the characteristics of addition and subtraction of integers. The design was implemented on 32 seventh grade students in one of the classes in a junior secondary school as the pilot experiment. Learning activities were observed thoroughly including the students’ responses that emerged during the learning activities. The written documentation of the students was also used to support the analysis in the learning activities. The results of the analysis showed that this method could help the students perform a large number of integer operations that could not be done with a number line. The teacher’s support as a didactical potential contract was still needed to encourage institutionalization processes. The results of the design analysis used as the basis of the revision are expected to be implemented by the teacher in the teaching experiment.

  12. Real-time Experiment Interface for Biological Control Applications

    PubMed Central

    Lin, Risa J.; Bettencourt, Jonathan; White, John A.; Christini, David J.; Butera, Robert J.

    2013-01-01

    The Real-time Experiment Interface (RTXI) is a fast and versatile real-time biological experimentation system based on Real-Time Linux. RTXI is open source and free, can be used with an extensive range of experimentation hardware, and can be run on Linux or Windows computers (when using the Live CD). RTXI is currently used extensively for two experiment types: dynamic patch clamp and closed-loop stimulation pattern control in neural and cardiac single cell electrophysiology. RTXI includes standard plug-ins for implementing commonly used electrophysiology protocols with synchronized stimulation, event detection, and online analysis. These and other user-contributed plug-ins can be found on the website (http://www.rtxi.org). PMID:21096883

  13. The CFVib Experiment: Control of Fluids in Microgravity with Vibrations

    NASA Astrophysics Data System (ADS)

    Fernandez, J.; Sánchez, P. Salgado; Tinao, I.; Porter, J.; Ezquerro, J. M.

    2017-10-01

    The Control of Fluids in Microgravity with Vibrations (CFVib) experiment was selected for the 2016 Fly Your Thesis! programme as part of the 65th ESA Parabolic Flight Campaign. The aim of the project is to observe the potentially complex behaviour of vibrated liquids in weightless environments and to investigate the extent to which small-amplitude vibrations can be used to influence and control this behaviour. Piezoelectric materials are used to generate high-frequency vibrations to drive surface waves and large-scale reorientation of the interface. The theory of vibroequilibria, which treats the quasi-stationary surface configurations achieved by this reorientation, was used to predict interesting parameter regimes and interpret fluid behaviour. Here we describe the scientific motivation, objectives, and design of the experiment.

  14. Lack of communication and control: experiences of distance caregivers of parents with advanced cancer.

    PubMed

    Mazanec, Polly; Daly, Barbara J; Ferrell, Betty Rolling; Prince-Paul, Maryjo

    2011-05-01

    To explore the new and complex phenomenon of distance caregiving in the advanced cancer population. Qualitative. A large comprehensive cancer center in the midwestern region of the United States. 14 distance caregivers of parents with advanced cancer. Patients with advanced lung, gastrointestinal, and gynecologic malignancies consented to have their distance caregiving adult children contacted to participate in the study. Responses to three open-ended questions guided the tape-recorded telephone interviews with the distance caregivers. Following transcription, content analysis with inductive coding was performed. Two major themes, communication and control, and five subthemes, benefits and burdens of distance caregiving, dealing with uncertainty, direct action through information seeking, protecting, and staying connected, emerged from the data. Distance caregivers experience some of the same stressors that local caregivers of patients with cancer experience. In addition, they have unique psychosocial needs related to the burden of geographic distance. Distance caregivers could benefit from nursing interventions targeted at their unique needs. Innovative interventions using Web-based computer technology for improved communication, as well as supportive care interventions, may be helpful.

  15. U.S. perspective on technology demonstration experiments for adaptive structures

    NASA Technical Reports Server (NTRS)

    Aswani, Mohan; Wada, Ben K.; Garba, John A.

    1991-01-01

    Evaluation of design concepts for adaptive structures is being performed in support of several focused research programs. These include programs such as Precision Segmented Reflector (PSR), Control Structure Interaction (CSI), and the Advanced Space Structures Technology Research Experiment (ASTREX). Although not specifically designed for adaptive structure technology validation, relevant experiments can be performed using the Passive and Active Control of Space Structures (PACOSS) testbed, the Space Integrated Controls Experiment (SPICE), the CSI Evolutionary Model (CEM), and the Dynamic Scale Model Test (DSMT) Hybrid Scale. In addition to the ground test experiments, several space flight experiments have been planned, including a reduced gravity experiment aboard the KC-135 aircraft, shuttle middeck experiments, and the Inexpensive Flight Experiment (INFLEX).

  16. Experiments with a small behaviour controlled planetary rover

    NASA Technical Reports Server (NTRS)

    Miller, David P.; Desai, Rajiv S.; Gat, Erann; Ivlev, Robert; Loch, John

    1993-01-01

    A series of experiments that were performed on the Rocky 3 robot is described. Rocky 3 is a small autonomous rover capable of navigating through rough outdoor terrain to a predesignated area, searching that area for soft soil, acquiring a soil sample, and depositing the sample in a container at its home base. The robot is programmed according to a reactive behavior control paradigm using the ALFA programming language. This style of programming produces robust autonomous performance while requiring significantly less computational resources than more traditional mobile robot control systems. The code for Rocky 3 runs on an eight bit processor and uses about ten k of memory.

  17. Closed-Loop HIRF Experiments Performed on a Fault Tolerant Flight Control Computer

    NASA Technical Reports Server (NTRS)

    Belcastro, Celeste M.

    1997-01-01

    ABSTRACT Closed-loop HIRF experiments were performed on a fault tolerant flight control computer (FCC) at the NASA Langley Research Center. The FCC used in the experiments was a quad-redundant flight control computer executing B737 Autoland control laws. The FCC was placed in one of the mode-stirred reverberation chambers in the HIRF Laboratory and interfaced to a computer simulation of the B737 flight dynamics, engines, sensors, actuators, and atmosphere in the Closed-Loop Systems Laboratory. Disturbances to the aircraft associated with wind gusts and turbulence were simulated during tests. Electrical isolation between the FCC under test and the simulation computer was achieved via a fiber optic interface for the analog and discrete signals. Closed-loop operation of the FCC enabled flight dynamics and atmospheric disturbances affecting the aircraft to be represented during tests. Upset was induced in the FCC as a result of exposure to HIRF, and the effect of upset on the simulated flight of the aircraft was observed and recorded. This paper presents a description of these closed- loop HIRF experiments, upset data obtained from the FCC during these experiments, and closed-loop effects on the simulated flight of the aircraft.

  18. Choice and Control Within Family Relationships: The Lived Experience of Adults With Intellectual Disability.

    PubMed

    Curryer, Bernadette; Stancliffe, Roger J; Dew, Angela; Wiese, Michele Y

    2018-06-01

    Increased choice and control is a driving force of current disability policy in Australia for people with disability and their families. Yet little is known of how adults with intellectual disability (ID) actually experience choice and control within their family relationships. We used interpretative phenomenological analysis of individual, semistructured interviews conducted with 8 Australian adults with ID to understand the meaning given to their experience of family support received around choice and decision making. Three themes were identified: (1) centrality of family, (2) experience of self-determination, and (3) limitations to choice and control. The participants identified trusted family members from whom guidance around choice and decision making was both sought and received, often involving mutual decision making and limitations to control.

  19. Comparative study of a learning fuzzy PID controller and a self-tuning controller.

    PubMed

    Kazemian, H B

    2001-01-01

    The self-organising fuzzy controller is an extension of the rule-based fuzzy controller with an additional learning capability. The self-organising fuzzy (SOF) is used as a master controller to readjust conventional PID gains at the actuator level during the system operation, copying the experience of a human operator. The application of the self-organising fuzzy PID (SOF-PID) controller to a 2-link non-linear revolute-joint robot-arm is studied using path tracking trajectories at the setpoint. For the purpose of comparison, the same experiments are repeated by using the self-tuning controller subject to the same data supplied at the setpoint. For the path tracking experiments, the output trajectories of the SOF-PID controller followed the specified path closer and smoother than the self-tuning controller.

  20. 10 CFR 63.44 - Changes, tests, and experiments.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Changes, tests, and experiments. 63.44 Section 63.44... experiments. (a) Definitions for the purposes of this section: (1) Change means a modification or addition to... isolation, are operated or controlled. (6) Tests or experiments not described in the SAR (as updated) means...

  1. 10 CFR 63.44 - Changes, tests, and experiments.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Changes, tests, and experiments. 63.44 Section 63.44... experiments. (a) Definitions for the purposes of this section: (1) Change means a modification or addition to... isolation, are operated or controlled. (6) Tests or experiments not described in the SAR (as updated) means...

  2. 10 CFR 63.44 - Changes, tests, and experiments.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Changes, tests, and experiments. 63.44 Section 63.44... experiments. (a) Definitions for the purposes of this section: (1) Change means a modification or addition to... isolation, are operated or controlled. (6) Tests or experiments not described in the SAR (as updated) means...

  3. The use of control groups in artificial grammar learning.

    PubMed

    Reber, Rolf; Perruchet, Pierre

    2003-01-01

    Experimenters assume that participants of an experimental group have learned an artificial grammar if they classify test items with significantly higher accuracy than does a control group without training. The validity of such a comparison, however, depends on an additivity assumption: Learning is superimposed on the action of non-specific variables-for example, repetitions of letters, which modulate the performance of the experimental group and the control group to the same extent. In two experiments we were able to show that this additivity assumption does not hold. Grammaticality classifications in control groups without training (Experiments 1 and 2) depended on non-specific features. There were no such biases in the experimental groups. Control groups with training on randomized strings (Experiment 2) showed fewer biases than did control groups without training. Furthermore, we reanalysed published research and demonstrated that earlier experiments using control groups without training had produced similar biases in control group performances, bolstering the finding that using control groups without training is methodologically unsound.

  4. Secure UNIX socket-based controlling system for high-throughput protein crystallography experiments.

    PubMed

    Gaponov, Yurii; Igarashi, Noriyuki; Hiraki, Masahiko; Sasajima, Kumiko; Matsugaki, Naohiro; Suzuki, Mamoru; Kosuge, Takashi; Wakatsuki, Soichi

    2004-01-01

    A control system for high-throughput protein crystallography experiments has been developed based on a multilevel secure (SSL v2/v3) UNIX socket under the Linux operating system. Main features of protein crystallography experiments (purification, crystallization, loop preparation, data collecting, data processing) are dealt with by the software. All information necessary to perform protein crystallography experiments is stored (except raw X-ray data, that are stored in Network File Server) in a relational database (MySQL). The system consists of several servers and clients. TCP/IP secure UNIX sockets with four predefined behaviors [(a) listening to a request followed by a reply, (b) sending a request and waiting for a reply, (c) listening to a broadcast message, and (d) sending a broadcast message] support communications between all servers and clients allowing one to control experiments, view data, edit experimental conditions and perform data processing remotely. The usage of the interface software is well suited for developing well organized control software with a hierarchical structure of different software units (Gaponov et al., 1998), which will pass and receive different types of information. All communication is divided into two parts: low and top levels. Large and complicated control tasks are split into several smaller ones, which can be processed by control clients independently. For communicating with experimental equipment (beamline optical elements, robots, and specialized experimental equipment etc.), the STARS server, developed at the Photon Factory, is used (Kosuge et al., 2002). The STARS server allows any application with an open socket to be connected with any other clients that control experimental equipment. Majority of the source code is written in C/C++. GUI modules of the system were built mainly using Glade user interface builder for GTK+ and Gnome under Red Hat Linux 7.1 operating system.

  5. The Importance of Experimental Design, Quality Assurance, and Control in Plant Metabolomics Experiments.

    PubMed

    Martins, Marina C M; Caldana, Camila; Wolf, Lucia Daniela; de Abreu, Luis Guilherme Furlan

    2018-01-01

    The output of metabolomics relies to a great extent upon the methods and instrumentation to identify, quantify, and access spatial information on as many metabolites as possible. However, the most modern machines and sophisticated tools for data analysis cannot compensate for inappropriate harvesting and/or sample preparation procedures that modify metabolic composition and can lead to erroneous interpretation of results. In addition, plant metabolism has a remarkable degree of complexity, and the number of identified compounds easily surpasses the number of samples in metabolomics analyses, increasing false discovery risk. These aspects pose a large challenge when carrying out plant metabolomics experiments. In this chapter, we address the importance of a proper experimental design taking into consideration preventable complications and unavoidable factors to achieve success in metabolomics analysis. We also focus on quality control and standardized procedures during the metabolomics workflow.

  6. Influence of phytogenic feed additive on Lawsonia intracellularis infection in pigs.

    PubMed

    Draskovic, Vladimir; Bosnjak-Neumuller, Jasna; Vasiljevic, Marko; Petrujkic, Branko; Aleksic, Nevenka; Kukolj, Vladimir; Stanimirovic, Zoran

    2018-03-01

    Lawsonia intracellularis is known to cause proliferative enteropathy (PE), one of the economically most important swine diseases with global distribution. Not unlike other enteric diseases, PE is a frequent indication for antibiotic therapy. However, their unjustified use leads to an emerging problem - antimicrobial resistance. Thus, the aim of this research was to assess if a phytogenic additive may replace antibiotics in the control of PE in 144 weaned piglets (72 treated and 72 controls) naturally infected with L. intracellularis. The quantity of L. intracellularis faecal shedding was monitored by real-time polymerase chain reaction (PCR) assay in faecal samples on day 0, 14 and 28, whilst the level of the ileum damage was determined by immunohistochemistry (IHC) assay performed on gut sections. Real-time PCR assay revealed that cycle-threshold (Ct) values in the treatment group increased significantly over time and were higher than in the control. These results indicate that the use of the phytogenic additive decreases the faecal excretion of L. intracellularis both throughout the experiment and in comparison to the control. The expression of the L. intracellularis antigen in IHC assay was lower in treated animals, implying that the additive leads to the decrease in the pathogen quantity in the ileum. Significantly higher feed conversion ratio was recorded in the treatment group. The results indicate that the phytogenic additive may be beneficial in the control of PE, but additional research is necessary to assess its use in various pig categories and define the optimum concentrations. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. A Neutral Control Condition for Hypnosis Experiments: "Wiki" Text.

    PubMed

    Varga, Katalin; Kekecs, Zoltán; Myhre, P S; Józsa, Emese

    2017-01-01

    A new control condition called Wiki is introduced. Key themes of each test suggestion of the Stanford Hypnotic Susceptibility Scale, Form C, were matched by a corresponding extract from Wikipedia.org. The authors compared phenomenological reports of participants across 4 conditions: hypnosis split into high and low hypnotizable subgroups, music, and Wiki condition, using the Phenomenology of Consciousness Inventory. High hypnotizables undergoing hypnosis reported higher altered experience and altered states of awareness than individuals in the Wiki condition, supporting the authors' hypothesis that the Wiki condition does not evoke an altered state of consciousness (internal dialogue, volitional control, and self-awareness did not differ). Wiki might be a viable control condition in hypnosis research given further examination.

  8. An active thermal control surfaces experiment. [spacecraft temperature determination

    NASA Technical Reports Server (NTRS)

    Wilkes, D. R.; Brown, M. J.

    1979-01-01

    An active flight experiment is described that has the objectives to determine the effects of the low earth natural environment and the Shuttle induced environment on selected thermal control and optical surfaces. The optical and thermal properties of test samples will be measured in-situ using an integrating sphere reflectrometer and using calorimetric methods. This experiment has been selected for the Long Duration Exposure Facility (LDEF) flight which will be carried to orbit by the NASA Space Shuttle. The LDEF will remain in orbit to be picked up by a later Shuttle mission and returned for postflight evaluation.

  9. Full-scale control of Mycolata foam by FEX-120 addition.

    PubMed

    Kragelund, C; Nilsson, B; Eskilsson, K; Bøgh, A M; Nielsen, P H

    2010-01-01

    Foaming incidents in activated sludge treatment plants are a worldwide problem and occur on a regular basis in both municipal and industrial activated sludge treatment plants. Foaming is most often caused by excessive growth of filamentous bacteria, especially the gram-positive ones affiliated within the Actinobacteria, e.g. the branched Mycolata or Candidatus Microthrix parvicella. Previous studies have shown that populations of Microthrix can be controlled by addition of certain polyaluminium compounds, but until now no effective chemicals have been identified to control other important foam formers such as the Mycolata. A new chemical (FilamentEx, FEX-120) was tested in full-scale in a Swedish wastewater treatment plant (WWTP) with immense foaming problems. In total, three different dosing events were carried out for more than 1 year. After only 8-17 weeks in each period, all foam had disappeared, and dosing of FEX-120 was stopped. Another 11 full-scale WWTPs in different countries were treated with FEX-120 because of severe Mycolata foaming on process tanks. In nine out of 11 plants, where the causative organisms were Gordonia or Skermania, a significant reduction of foam up to 100% was observed after treatment for approx. 10 weeks. In two WWTPs with unknown Mycolata organisms, no reduction was observed.

  10. Trained Eyes: Experience Promotes Adaptive Gaze Control in Dynamic and Uncertain Visual Environments

    PubMed Central

    Taya, Shuichiro; Windridge, David; Osman, Magda

    2013-01-01

    Current eye-tracking research suggests that our eyes make anticipatory movements to a location that is relevant for a forthcoming task. Moreover, there is evidence to suggest that with more practice anticipatory gaze control can improve. However, these findings are largely limited to situations where participants are actively engaged in a task. We ask: does experience modulate anticipative gaze control while passively observing a visual scene? To tackle this we tested people with varying degrees of experience of tennis, in order to uncover potential associations between experience and eye movement behaviour while they watched tennis videos. The number, size, and accuracy of saccades (rapid eye-movements) made around ‘events,’ which is critical for the scene context (i.e. hit and bounce) were analysed. Overall, we found that experience improved anticipatory eye-movements while watching tennis clips. In general, those with extensive experience showed greater accuracy of saccades to upcoming event locations; this was particularly prevalent for events in the scene that carried high uncertainty (i.e. ball bounces). The results indicate that, even when passively observing, our gaze control system utilizes prior relevant knowledge in order to anticipate upcoming uncertain event locations. PMID:23951147

  11. Phytoplankton growth response to Asian dust addition in the northwest Pacific Ocean versus the Yellow Sea

    NASA Astrophysics Data System (ADS)

    Zhang, Chao; Gao, Huiwang; Yao, Xiaohong; Shi, Zongbo; Shi, Jinhui; Yu, Yang; Meng, Ling; Guo, Xinyu

    2018-02-01

    In this study, five on-board microcosm experiments were performed in the subtropical gyre, the Kuroshio Extension region of the northwest Pacific Ocean (NWPO), and the Yellow Sea (YS) in order to investigate phytoplankton growth following the addition of artificially modified mineral dust (AM dust) and various nutrients (nitrogen (N), phosphorus (P), iron (Fe), N + P, and N + P + Fe). The two experiments carried out with AM-dust addition in the subtropical gyre showed a maximum chlorophyll a (Chl a) concentration increase of 1.7- and 2.8-fold, while the cell abundance of large-sized phytoplankton ( > 5 µm) showed a 1.8- and 3.9-fold increase, respectively, relative to the controls. However, in the Kuroshio Extension region and the YS, the increases in maximum Chl a and cell abundance of large-sized phytoplankton following AM-dust addition were at most 1.3-fold and 1.7-fold larger than those in the controls, respectively. A net conversion efficiency index (NCEI) newly proposed in this study, size-fractionated Chl a, and the abundance of large-sized phytoplankton were analysed to determine which nutrients contribute to supporting phytoplankton growth. Our results demonstrate that a combination of nutrients, N-P or N + P + Fe, is responsible for phytoplankton growth in the subtropical gyre following AM-dust addition. Single nutrient addition, i.e., N in the Kuroshio Extension region and P or N in the YS, controls the phytoplankton growth following AM-dust addition. In the AM-dust-addition experiments, in which the increased N-P or P was identified to determine phytoplankton growth, the dissolved inorganic P from AM dust (8.6 nmol L-1) was much lower than the theoretically estimated minimum P demand (˜ 20 nmol L-1) for phytoplankton growth. These observations suggest that additional supply augments the bioavailable P stock in incubated seawater with AM-dust addition, most likely due to an enhanced solubility of P from AM dust or the remineralization of the dissolved

  12. Effect of food additives on hyperphosphatemia among patients with end-stage renal disease: a randomized controlled trial.

    PubMed

    Sullivan, Catherine; Sayre, Srilekha S; Leon, Janeen B; Machekano, Rhoderick; Love, Thomas E; Porter, David; Marbury, Marquisha; Sehgal, Ashwini R

    2009-02-11

    High dietary phosphorus intake has deleterious consequences for renal patients and is possibly harmful for the general public as well. To prevent hyperphosphatemia, patients with end-stage renal disease limit their intake of foods that are naturally high in phosphorus. However, phosphorus-containing additives are increasingly being added to processed and fast foods. The effect of such additives on serum phosphorus levels is unclear. To determine the effect of limiting the intake of phosphorus-containing food additives on serum phosphorus levels among patients with end-stage renal disease. Cluster randomized controlled trial at 14 long-term hemodialysis facilities in northeast Ohio. Two hundred seventy-nine patients with elevated baseline serum phosphorus levels (>5.5 mg/dL) were recruited between May and October 2007. Two shifts at each of 12 large facilities and 1 shift at each of 2 small facilities were randomly assigned to an intervention or control group. Intervention participants (n=145) received education on avoiding foods with phosphorus additives when purchasing groceries or visiting fast food restaurants. Control participants (n=134) continued to receive usual care. Change in serum phosphorus level after 3 months. At baseline, there was no significant difference in serum phosphorus levels between the 2 groups. After 3 months, the decline in serum phosphorus levels was 0.6 mg/dL larger among intervention vs control participants (95% confidence interval, -1.0 to -0.1 mg/dL). Intervention participants also had statistically significant increases in reading ingredient lists (P<.001) and nutrition facts labels (P = .04) but no significant increase in food knowledge scores (P = .13). Educating end-stage renal disease patients to avoid phosphorus-containing food additives resulted in modest improvements in hyperphosphatemia. clinicaltrials.gov Identifier: NCT00583570.

  13. A Randomized Controlled Trial Examining the Effect of the Addition of the Mandibular Block to Cervical Plexus Block for Carotid Endarterectomy.

    PubMed

    Kavrut Ozturk, Nilgun; Kavakli, Ali Sait; Sagdic, Kadir; Inanoglu, Kerem; Umot Ayoglu, Raif

    2018-04-01

    Although the cervical plexus block generally provides adequate analgesia for carotid endarterectomy, pain caused by metal retractors on the inferior surface of the mandible is not prevented by the cervical block. Different pain relief methods can be performed for patients who experience discomfort in these areas. In this study, the authors evaluated the effect of mandibular block in addition to cervical plexus block on pain scores in carotid endarterectomy. A prospective, randomized, controlled trial. Training and research hospital. Patients who underwent a carotid endarterectomy. Patients scheduled for carotid endarterectomy under cervical plexus block were randomized into 2 groups: group 1 (those who did not receive a mandibular block) and group 2 (those who received a mandibular block). The main purpose of the study was to evaluate the mandibular block in addition to cervical plexus block in terms of intraoperative pain scores. Intraoperative visual analog scale scores were significantly higher in group 1 (p = 0.001). The amounts of supplemental 1% lidocaine and intraoperative intravenous analgesic used were significantly higher in group 1 (p = 0.001 and p = 0.035, respectively). Patient satisfaction scores were significantly lower in group 1 (p = 0.044). The amount of postoperative analgesic used, time to first analgesic requirement, postoperative visual analog scale scores, and surgeon satisfaction scores were similar in both groups. There was no significant difference between the groups with respect to complications. No major neurologic deficits or perioperative mortality were observed. Mandibular block in addition to cervical plexus block provides better intraoperative pain control and greater patient satisfaction than cervical plexus block alone. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Adaptive dynamic programming approach to experience-based systems identification and control.

    PubMed

    Lendaris, George G

    2009-01-01

    Humans have the ability to make use of experience while selecting their control actions for distinct and changing situations, and their process speeds up and have enhanced effectiveness as more experience is gained. In contrast, current technological implementations slow down as more knowledge is stored. A novel way of employing Approximate (or Adaptive) Dynamic Programming (ADP) is described that shifts the underlying Adaptive Critic type of Reinforcement Learning method "up a level", away from designing individual (optimal) controllers to that of developing on-line algorithms that efficiently and effectively select designs from a repository of existing controller solutions (perhaps previously developed via application of ADP methods). The resulting approach is called Higher-Level Learning Algorithm. The approach and its rationale are described and some examples of its application are given. The notions of context and context discernment are important to understanding the human abilities noted above. These are first defined, in a manner appropriate to controls and system-identification, and as a foundation relating to the application arena, a historical view of the various phases during development of the controls field is given, organized by how the notion 'context' was, or was not, involved in each phase.

  15. Out-reach in-space technology experiments program: Control of flexible robot manipulators in zero gravity, experiment definition phase

    NASA Technical Reports Server (NTRS)

    Phillips, Warren F.

    1989-01-01

    The results obtained show that it is possible to control light-weight robots with flexible links in a manner that produces good response time and does not induce unacceptable link vibrations. However, deflections induced by gravity cause large static position errors with such a control system. For this reason, it is not possible to use this control system for controlling motion in the direction of gravity. The control system does, on the other hand, have potential for use in space. However, in-space experiments will be needed to verify its applicability to robots moving in three dimensions.

  16. An experiment in software reliability

    NASA Technical Reports Server (NTRS)

    Dunham, J. R.; Pierce, J. L.

    1986-01-01

    The results of a software reliability experiment conducted in a controlled laboratory setting are reported. The experiment was undertaken to gather data on software failures and is one in a series of experiments being pursued by the Fault Tolerant Systems Branch of NASA Langley Research Center to find a means of credibly performing reliability evaluations of flight control software. The experiment tests a small sample of implementations of radar tracking software having ultra-reliability requirements and uses n-version programming for error detection, and repetitive run modeling for failure and fault rate estimation. The experiment results agree with those of Nagel and Skrivan in that the program error rates suggest an approximate log-linear pattern and the individual faults occurred with significantly different error rates. Additional analysis of the experimental data raises new questions concerning the phenomenon of interacting faults. This phenomenon may provide one explanation for software reliability decay.

  17. Stratospheric controlled perturbation experiment: a small-scale experiment to improve understanding of the risks of solar geoengineering

    PubMed Central

    Dykema, John A.; Keith, David W.; Anderson, James G.; Weisenstein, Debra

    2014-01-01

    Although solar radiation management (SRM) through stratospheric aerosol methods has the potential to mitigate impacts of climate change, our current knowledge of stratospheric processes suggests that these methods may entail significant risks. In addition to the risks associated with current knowledge, the possibility of ‘unknown unknowns’ exists that could significantly alter the risk assessment relative to our current understanding. While laboratory experimentation can improve the current state of knowledge and atmospheric models can assess large-scale climate response, they cannot capture possible unknown chemistry or represent the full range of interactive atmospheric chemical physics. Small-scale, in situ experimentation under well-regulated circumstances can begin to remove some of these uncertainties. This experiment—provisionally titled the stratospheric controlled perturbation experiment—is under development and will only proceed with transparent and predominantly governmental funding and independent risk assessment. We describe the scientific and technical foundation for performing, under external oversight, small-scale experiments to quantify the risks posed by SRM to activation of halogen species and subsequent erosion of stratospheric ozone. The paper's scope includes selection of the measurement platform, relevant aspects of stratospheric meteorology, operational considerations and instrument design and engineering. PMID:25404681

  18. Problems in air traffic management. IV., Comparison of pre-employment, job-related experience with aptitude tests as predictors of training and job performance of air traffic control specialists.

    DOT National Transportation Integrated Search

    1963-12-01

    In addition to passing a second class aviation medical examination, individuals applying for training as an Air Traffic Control Specialist (ATCS) with the Federal Aviation Agency have, in the past, been required to have previous experience which was ...

  19. Additional Layers of Violence: The Intersections of Gender and Disability in the Violence Experiences of Women With Physical Disabilities in South Africa.

    PubMed

    van der Heijden, Ingrid; Abrahams, Naeemah; Harries, Jane

    2016-04-27

    South Africa has unprecedented levels of violence and many South African women are exposed to violence during their lifetime. This article explores how gender and disability intersect in women's experiences of violence during their lifetime. Repeat in-depth qualitative interviews with 30 physically disabled women in Cape Town reveal that women with physical disabilities are exposed to various forms of violence, and shows how their impairments shape their violence experiences. The most common forms of violence women with disabilities experience are psychological violence, financial abuse, neglect, and deprivation, with disability stigma playing a central role and contributing to how women with disabilities are exploited and dehumanized. Constructions of women as asexual shape their sexual relationships and experiences of sexual violence. This article identifies that women with disabilities are more at risk and experience additional layers of violence than women without disabilities. These additional risks and layers of violence need to be recognized and inform interventions to prevent and respond to violence against women with disabilities in the country. Prevention of violence against women with physical disabilities in South Africa needs to address the role of disability stigma that shapes the types of violence they experience, change gender norms, and create accessible and safe environments and economic empowerment opportunities. © The Author(s) 2016.

  20. Additive Manufacturing, Design, Testing, and Fabrication: A Full Engineering Experience at JSC

    NASA Technical Reports Server (NTRS)

    Zusack, Steven

    2016-01-01

    I worked on several projects this term. While most projects involved additive manufacturing, I was also involved with two design projects, two testing projects, and a fabrication project. The primary mentor for these was Richard Hagen. Secondary mentors were Hai Nguyen, Khadijah Shariff, and fabrication training from James Brown. Overall, my experience at JSC has been successful and what I have learned will continue to help me in my engineering education and profession long after I leave. My 3D printing projects ranged from less than a 1 cubic centimeter to about 1 cubic foot and involved several printers using different printing technologies. It was exciting to become familiar with printing technologies such as industrial grade FDM (Fused Deposition Modeling), the relatively new SLA (Stereolithography), and PolyJet. My primary duty with the FDM printers was to model parts that came in from various sources to print effectively and efficiently. Using methods my mentor taught me and the Stratasys Insight software, I was able to minimize imperfections, hasten build time, improve strength for specific forces (tensile, shear, etc...), and reduce likelihood of a print-failure. Also using FDM, I learned how to repair a part after it was printed. This is done by using a special kind of glue that chemically melts the two faces of plastic parts together to form a fused interface. My first goal with SLA technology was to bring the printer back to operational readiness. In becoming familiar with the Pegasus SLA printer, I researched the leveling, laser settings, and different vats to hold liquid material. With this research, I was successfully able to bring the Pegasus back online and have successfully printed multiple sample parts as well as functional parts. My experience with PolyJet technology has been focused on an understanding of the abilities/limits, costs, and the maintenance for daily use. Still upcoming will be experience with using a composite printer that uses FDM

  1. The 5th Annual NASA Spacecraft Control Laboratory Experiment (SCOLE) Workshop, part 2

    NASA Technical Reports Server (NTRS)

    Taylor, Lawrence W., Jr. (Compiler)

    1990-01-01

    A collection of papers from the workshop are presented. The topics addressed include: the modeling, systems identification, and control synthesis for the Spacecraft Control Laboratory Experiment (SCOLE) configuration.

  2. Using Controlled Landslide Initiation Experiments to Test Limit-Equilibrium Analyses of Slope Stability

    NASA Astrophysics Data System (ADS)

    Reid, M. E.; Iverson, R. M.; Brien, D. L.; Iverson, N. R.; Lahusen, R. G.; Logan, M.

    2004-12-01

    Most studies of landslide initiation employ limit equilibrium analyses of slope stability. Owing to a lack of detailed data, however, few studies have tested limit-equilibrium predictions against physical measurements of slope failure. We have conducted a series of field-scale, highly controlled landslide initiation experiments at the USGS debris-flow flume in Oregon; these experiments provide exceptional data to test limit equilibrium methods. In each of seven experiments, we attempted to induce failure in a 0.65m thick, 2m wide, 6m3 prism of loamy sand placed behind a retaining wall in the 31° sloping flume. We systematically investigated triggering of sliding by groundwater injection, by prolonged moderate-intensity sprinkling, and by bursts of high intensity sprinkling. We also used vibratory compaction to control soil porosity and thereby investigate differences in failure behavior of dense and loose soils. About 50 sensors were monitored at 20 Hz during the experiments, including nests of tiltmeters buried at 7 cm spacing to define subsurface failure geometry, and nests of tensiometers and pore-pressure sensors to define evolving pore-pressure fields. In addition, we performed ancillary laboratory tests to measure soil porosity, shear strength, hydraulic conductivity, and compressibility. In loose soils (porosity of 0.52 to 0.55), abrupt failure typically occurred along the flume bed after substantial soil deformation. In denser soils (porosity of 0.41 to 0.44), gradual failure occurred within the soil prism. All failure surfaces had a maximum length to depth ratio of about 7. In even denser soil (porosity of 0.39), we could not induce failure by sprinkling. The internal friction angle of the soils varied from 28° to 40° with decreasing porosity. We analyzed stability at failure, given the observed pore-pressure conditions just prior to large movement, using a 1-D infinite-slope method and a more complete 2-D Janbu method. Each method provides a static

  3. Viewing Artworks: Contributions of Cognitive Control and Perceptual Facilitation to Aesthetic Experience

    ERIC Educational Resources Information Center

    Cupchik, Gerald C.; Vartanian, Oshin; Crawley, Adrian; Mikulis, David J.

    2009-01-01

    When we view visual images in everyday life, our perception is oriented toward object identification. In contrast, when viewing visual images "as artworks", we also tend to experience subjective reactions to their stylistic and structural properties. This experiment sought to determine how cognitive control and perceptual facilitation contribute…

  4. EURECA mission control experience and messages for the future

    NASA Technical Reports Server (NTRS)

    Huebner, H.; Ferri, P.; Wimmer, W.

    1994-01-01

    EURECA is a retrievable space platform which can perform multi-disciplinary scientific and technological experiments in a Low Earth Orbit for a typical mission duration of six to twelve months. It is deployed and retrieved by the NASA Space Shuttle and is designed to support up to five flights. The first mission started at the end of July 1992 and was successfully completed with the retrieval in June 1993. The operations concept and the ground segment for the first EURECA mission are briefly introduced. The experiences in the preparation and the conduction of the mission from the flight control team point of view are described.

  5. Dynamics and control simulation of the Spacelab Experiment Pointing Mount

    NASA Technical Reports Server (NTRS)

    Marsh, E. L.; Ward, R. S.

    1977-01-01

    Computer simulations were developed to evaluate the performance of four Experiment Pointing Mounts (EPM) being considered for Spacelab experiments in the 1980-1990 time frame. The system modeled compromises a multibody system consisting of the shuttle, a mechanical isolation device, the EPM, celestial and inertial sensors, bearings, gimbal torque motors and associated nonlinearities, the experiment payload, and control and estimator algorithms. Each mount was subjected to a common disturbance (shuttle vernier thruster firing and man push off) and command (stellar pointing or solar raster scan) input. The fundamental limitation common to all mounts was found to be sensor noise. System dynamics and hardware nonlinearities have secondary effects on pointing performance for sufficiently high bandwidth.

  6. CSM digital autopilot testing in support of ASTP experiments control requirements

    NASA Technical Reports Server (NTRS)

    Rue, D. L.

    1975-01-01

    Results are presented of CSM digital autopilot (DAP) testing. The testing was performed to demonstrate and evaluate control modes which are currently planned or could be considered for use in support of experiments on the ASTP mission. The testing was performed on the Lockheed Guidance, Navigation, and Control System Functional Simulator (GNCFS). This simulator, which was designed to test the Apollo and Skylab DAP control system, has been used extensively and is a proven tool for CSM DAP analysis.

  7. Coping with Unusual ExperienceS for 12-18 year olds (CUES+): a transdiagnostic randomised controlled trial of the effectiveness of cognitive therapy in reducing distress associated with unusual experiences in adolescent mental health services: study protocol for a randomised controlled trial.

    PubMed

    Jolley, Suzanne; Browning, Sophie; Corrigall, Richard; Laurens, Kristin R; Hirsch, Colette; Bracegirdle, Karen; Gin, Kimberley; Muccio, Francesca; Stewart, Catherine; Banerjea, Partha; Kuipers, Elizabeth; Garety, Philippa; Byrne, Majella; Onwumere, Juliana; Achilla, Evanthia; McCrone, Paul; Emsley, Richard

    2017-12-04

    Childhood 'unusual experiences' (such as hearing voices that others cannot, or suspicions of being followed) are common, but can become more distressing during adolescence, especially for young people in contact with Child and Adolescent Mental Health Services (CAMHS). Unusual experiences that are distressing or have adverse life impact (UEDs) are associated with a range of current and future emotional, behavioural and mental health difficulties. Recommendations for psychological intervention are based on evidence from adult studies, with some support from small, pilot, child-specific evaluations. Research is needed to ensure that the recommendations suit children as well as adults. The CUES+ study (Coping with Unusual ExperienceS for 12-18 year olds) aims to find out whether cognitive behaviour therapy for UEDs (CBT-UED) is a helpful and cost-effective addition to usual community care for 12-18 year olds presenting to United Kingdom National Health Service Child and Adolescent Mental Health Services in four London boroughs. The CUES+ study is a randomised controlled trial comparing CBT-UED plus routine care to routine care alone. CBT-UED comprises up to 16 sessions, including up to 12 individual and up to four family support meetings, each lasting around 45-60 min, delivered weekly. The primary outcome is emotional distress. Secondary outcomes are change in UEDs, risk events (self-harm, attendance at emergency services, other adverse events) and health economic outcomes. Participants will be randomised in a 1:1 ratio after baseline assessment. Randomisation will be stratified by borough and by severity of mental health presentation: 'severe' (an identified psychotic or bipolar disorder) or any 'other' condition. Outcomes will be assessed by a trained assessor blind to treatment condition at 0, 16 and 24 weeks. Recruitment began in February, 2015 and is ongoing until the end of March, 2017. The CUES+ study will contribute to the currently limited child

  8. The food additive vanillic acid controls transgene expression in mammalian cells and mice.

    PubMed

    Gitzinger, Marc; Kemmer, Christian; Fluri, David A; El-Baba, Marie Daoud; Weber, Wilfried; Fussenegger, Martin

    2012-03-01

    Trigger-inducible transcription-control devices that reversibly fine-tune transgene expression in response to molecular cues have significantly advanced the rational reprogramming of mammalian cells. When designed for use in future gene- and cell-based therapies the trigger molecules have to be carefully chosen in order to provide maximum specificity, minimal side-effects and optimal pharmacokinetics in a mammalian organism. Capitalizing on control components that enable Caulobacter crescentus to metabolize vanillic acid originating from lignin degradation that occurs in its oligotrophic freshwater habitat, we have designed synthetic devices that specifically adjust transgene expression in mammalian cells when exposed to vanillic acid. Even in mice transgene expression was robust, precise and tunable in response to vanillic acid. As a licensed food additive that is regularly consumed by humans via flavoured convenience food and specific fresh vegetable and fruits, vanillic acid can be considered as a safe trigger molecule that could be used for diet-controlled transgene expression in future gene- and cell-based therapies.

  9. Unconscious Modulation of the Conscious Experience of Voluntary Control

    ERIC Educational Resources Information Center

    Linser, Katrin; Goschke, Thomas

    2007-01-01

    How does the brain generate our experience of being in control over our actions and their effects? Here, we argue that the perception of events as self-caused emerges from a comparison between anticipated and actual action-effects: if the representation of an event that follows an action is activated before the action, the event is experienced as…

  10. The effect of leachate recirculation with enzyme cellulase addition on waste stability in landfill bioreactor

    NASA Astrophysics Data System (ADS)

    Saffira, N.; Kristanto, G. A.

    2018-01-01

    Landfill bioreactor with leachate recirculation is known to enhance waste stabilization. However, the composition of waste in Indonesia is comprised by organic waste which is lignocellulosic materials that considered take a long time to degrade under anaerobic condition. To accelerate the degradation process, enzyme addition is ought to do. Cellulase is an enzyme that can catalyse cellulose and other polysaccharide decomposition processes. Therefore, operation of waste degradation using leachate recirculation with a cellulase addition to enhance waste stabilization was investigated using anaerobic bioreactor landfill. The experiment was performed on 2 conditions; leachate recirculation with cellulase addition and recirculation only as a control. The addition of cellulase is reported to be significant in decreasing organic content, represented by volatile solid parameter. The volatile solid reduction in the cellulase augmented reactor and control reactor was 17.86% and 7.90%, respectively. Cellulase addition also resulted in the highest cellulose reduction. Settlement of the landfill in a bioreactor with enzyme addition (32.67%) was reported to be higher than the control (19.33%). Stabilization of landfill review by the decreasing rate constant of the cellulose and lignin ratio parameter was more rapidly achieved by the enzyme addition (0.014 day-1) compared to control (0.002 day-1).

  11. Development of Skylab experiment T020 employing a foot controlled maneuvering unit

    NASA Technical Reports Server (NTRS)

    Hewes, D. E.; Glover, K. E.

    1972-01-01

    A review of the plans and preparations is presented for Skylab experiment T020, entitled Foot-Controlled Maneuvering Unit (FCMU). The FCMU is an experimental system intended to explore the use of simple astronaut maneuvering devices in the zero-gravity environment of space. This review also includes discussions of the FCMU concept and experiment hardware systems, as well as supporting experiment definition and development research studies conducted with the aid of zero-gravity simulators.

  12. Thermal analysis of laser additive manufacturing of aluminium alloys: Experiment and simulation

    NASA Astrophysics Data System (ADS)

    Bock, Frederic E.; Froend, Martin; Herrnring, Jan; Enz, Josephin; Kashaev, Nikolai; Klusemann, Benjamin

    2018-05-01

    Laser additive manufacturing (LAM) has become increasingly popular in industry in recent decades because it enables exceptional degrees of freedom regarding the structural design of lightweight components compared to subtractive manufacturing techniques. Laser metal deposition (LMD) of wire-fed material shows in particular the advantages such as high process velocity and efficient use of material compared to other LAM processes. During wire-based LMD, the material is deposited onto a substrate and supplemented by successive layers allowing a layer-wise production of complex three-dimensional structures. Despite the increased productivity of LMD, regarding the ability to process aluminium alloys, there is still a lack in quality and reproducibility due to the inhomogeneous temperature distribution during the process, leading to undesired residual stresses, distortions and inconsistent layer geometries and poor microstructures. In this study, the aluminium alloy AA5087 as wire and AA5754 as substrate material were utilized for LMD. In order to obtain information about the temperature field during LMD, thermocouple and thermography measurements were performed during the process. The temperature measurements were used to validate a finite element model regarding the heat distribution, which will be further used to investigate the temperature field evolution over time. To consider the continuous addition of material within the FE-model, an inactive/active element approach was chosen, where initially deactivated elements are activated corresponding to the deposition of material. The first results of the simulation and the experiments show good agreement. Therefore, the model can be used in the future for LMD process optimization, e.g., in terms of minimizing local variations of the thermal load for each layer.

  13. Therapist Experience and Knowledge Acquisition in Internet-Delivered CBT for Social Anxiety Disorder: A Randomized Controlled Trial

    PubMed Central

    Andersson, Gerhard; Carlbring, Per; Furmark, Tomas

    2012-01-01

    Background Guided internet-delivered cognitive behavior therapy (ICBT) has been tested in several trials on social anxiety disorder (SAD) with moderate to large effects. The aims of this study were threefold. First, to compare the effects of ICBT including online discussion forum with a moderated online discussion forum only. Second, to investigate if knowledge about SAD increased following treatment and third to compare the effects of inexperienced versus experienced therapists on patient outcomes. Methods A total of 204 participants with a primary diagnosis of SAD were included and randomized to either guided ICBT or the control condition. ICBT consisted of a 9-week treatment program which was guided by either psychology students at MSc level (n = 6) or by licensed psychologists with previous experience of ICBT (n = 7). A knowledge test dealing with social anxiety was administered before and after treatment. Measures of social anxiety and secondary outcomes dealing with general anxiety, depression, and quality of life were administered before and after treatment. In addition, a 1-year follow-up was conducted on the treated individuals. Results Immediately following treatment, the ICBT group showed superior outcome on the Liebowitz Social Anxiety Scale self-report version with a between group posttreatment Hedges g effect size of g = 0.75. In addition, significant differences on all the secondary outcomes were observed. Gains were well maintained one year later. Knowledge, as assessed by the knowledge test, increased following treatment with little gain in the control group. Therapist experience did not result in different outcomes, but experienced therapists logged in less frequently compared to the inexperienced therapists, suggesting that they needed less time to support patients. Discussion We conclude that guided ICBT reduce symptoms of SAD, increase knowledge about SAD and that therapist experience does not make a difference apart from the

  14. Which daily experiences can foster well-being at work? A diary study on the interplay between flow experiences, affective commitment, and self-control demands.

    PubMed

    Rivkin, Wladislaw; Diestel, Stefan; Schmidt, Klaus-Helmut

    2018-01-01

    Previous research has provided strong evidence for affective commitment as a direct predictor of employees' psychological well-being and as a resource that buffers the adverse effects of self-control demands as a stressor. However, the mechanisms that underlie the beneficial effects of affective commitment have not been examined yet. Drawing on the self-determination theory, we propose day-specific flow experiences as the mechanism that underlies the beneficial effects of affective commitment, because flow experiences as peaks of intrinsic motivation constitute manifestations of autonomous regulation. In a diary study covering 10 working days with N = 90 employees, we examine day-specific flow experiences as a mediator of the beneficial effects of interindividual affective commitment and a buffering moderator of the adverse day-specific effects of self-control demands on indicators of well-being (ego depletion, need for recovery, work engagement, and subjective vitality). Our results provide strong support for our predictions that day-specific flow experiences a) mediate the beneficial effects of affective commitment on employees' day-specific well-being and b) moderate (buffer) the adverse day-specific effects of self-control demands on well-being. That is, on days with high levels of flow experiences, employees were better able to cope with self-control demands whereas self-control demands translated into impaired well-being when employees experienced lower levels of day-specific flow experiences. We then discuss our findings and suggest practical implications. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  15. Loophole-free Bell test using electron spins in diamond: second experiment and additional analysis

    PubMed Central

    Hensen, B.; Kalb, N.; Blok, M. S.; Dréau, A. E.; Reiserer, A.; Vermeulen, R. F. L.; Schouten, R. N.; Markham, M.; Twitchen, D. J.; Goodenough, K.; Elkouss, D.; Wehner, S.; Taminiau, T. H.; Hanson, R.

    2016-01-01

    The recently reported violation of a Bell inequality using entangled electronic spins in diamonds (Hensen et al., Nature 526, 682–686) provided the first loophole-free evidence against local-realist theories of nature. Here we report on data from a second Bell experiment using the same experimental setup with minor modifications. We find a violation of the CHSH-Bell inequality of 2.35 ± 0.18, in agreement with the first run, yielding an overall value of S = 2.38 ± 0.14. We calculate the resulting P-values of the second experiment and of the combined Bell tests. We provide an additional analysis of the distribution of settings choices recorded during the two tests, finding that the observed distributions are consistent with uniform settings for both tests. Finally, we analytically study the effect of particular models of random number generator (RNG) imperfection on our hypothesis test. We find that the winning probability per trial in the CHSH game can be bounded knowing only the mean of the RNG bias. This implies that our experimental result is robust for any model underlying the estimated average RNG bias, for random bits produced up to 690 ns too early by the random number generator. PMID:27509823

  16. Apollo experience report: Crew station integration. Volume 2: Crew station displays and controls

    NASA Technical Reports Server (NTRS)

    Langdoc, W. A.; Nassman, D. A.

    1975-01-01

    The functional requirements for the Apollo displays and controls system are presented. The configuration of the displays, controls, and panels for both the command module and the lunar module are described, and the design development and operational experience of the displays and controls system are discussed. Pertinent recommendations for future displays and controls system design efforts are made.

  17. Design of control software for the closed ecology experiment facilities (CEEF)

    NASA Astrophysics Data System (ADS)

    Miyajima, H.; Abe, K.; Hirosaki, T.; Ishikawa, Y.

    A habitation experiment using a closed ecology experiment facilities CEEF was started in fiscal 2005 three experiments in which two humans stayed for one week were conducted Their stays will be extended gradually until fiscal 2009 when an experiment will be launched with two humans staying for four months The CEEF has an ambitious target of acquiring the technology of an advanced life support system and the system is being developed based on the technology of conventional plant systems Especially in respect to supervision and control of the system the system still has little automation This system has many manual operation parts whose starts and stops are determined by human judgment There are even several parts requiring off-line measurements that include analyses performed by hand At present a CEEF behavioral prediction system CPS is being developed as the first stage for controlling such a system In this CPS an operator creates an operational schedule after due consideration However creation of the operational schedule of the complex CEEF is not easy and it is above the operator s capability to fully cope with alterations of the operational schedule that occur during a long-term habitation experiment Therefore we are going to develop an automatic creation function of the operational schedule that will be incorporated into the CPS by the beginning of the habitation experiment in fiscal 2009 This function will enable automation of most of the operational schedule that human operators currently set up In this paper we examine

  18. Experience with synchronous and asynchronous digital control systems. [for flight

    NASA Technical Reports Server (NTRS)

    Regenie, Victoria A.; Chacon, Claude V.; Lock, Wilton P.

    1986-01-01

    Flight control systems have undergone a revolution since the days of simple mechanical linkages; presently the most advanced systems are full-authority, full-time digital systems controlling unstable aircraft. With the use of advanced control systems, the aerodynamic design can incorporate features that allow greater performance and fuel savings, as can be seen on the new Airbus design and advanced tactical fighter concepts. These advanced aircraft will be and are relying on the flight control system to provide the stability and handling qualities required for safe flight and to allow the pilot to control the aircraft. Various design philosophies have been proposed and followed to investigate system architectures for these advanced flight control systems. One major area of discussion is whether a multichannel digital control system should be synchronous or asynchronous. This paper addressed the flight experience at the Dryden Flight Research Facility of NASA's Ames Research Center with both synchronous and asynchronous digital flight control systems. Four different flight control systems are evaluated against criteria such as software reliability, cost increases, and schedule delays.

  19. Revealing Student Thinking about Experimental Design and the Roles of Control Experiments

    ERIC Educational Resources Information Center

    Shi, Jia; Power, Joy M.; Klymkowsky, Michael W.

    2011-01-01

    Well-designed "controls" distinguish experimental from non-experimental studies. Surprisingly, we found that a high percentage of students had difficulty identifying control experiments even after completing three university-level laboratory courses. To address this issue, we designed and ran a revised cell biology lab course in which…

  20. Optical proposals for controlled delayed-choice experiment based on weak cross-Kerr nonlinearities

    NASA Astrophysics Data System (ADS)

    Dong, Li; Lin, Yan-Fang; Li, Qing-Yang; Xiu, Xiao-Ming; Dong, Hai-Kuan; Gao, Ya-Jun

    2017-05-01

    Employing polarization modes of a photon, we propose two theoretical proposals to exhibit the wave-particle duality of the photon with the assistance of weak cross-Kerr nonlinearities. The first proposal is a classical controlled delayed-choice experiment (that is, Wheeler's delayed-choice experiment), where we can observe selectively wave property or particle property of the photon relying on the experimenter's selection, whereas the second proposal is a quantum controlled delayed-choice experiment, by which the mixture phenomenon of a wave and a particle will be exhibited. Both of them can be realized with near-unity probability and embody the charming characteristics of quantum mechanics. The employment of the mature techniques and simple operations (e.g., Homodyne measurement, classical feed forward, and single-photon transformations) provides the feasibility of the delayed-choice experiment proposals presented here.

  1. Organic Matter and Water Addition Enhance Soil Respiration in an Arid Region

    PubMed Central

    Lai, Liming; Wang, Jianjian; Tian, Yuan; Zhao, Xuechun; Jiang, Lianhe; Chen, Xi; Gao, Yong; Wang, Shaoming; Zheng, Yuanrun

    2013-01-01

    Climate change is generally predicted to increase net primary production, which could lead to additional C input to soil. In arid central Asia, precipitation has increased and is predicted to increase further. To assess the combined effects of these changes on soil CO2 efflux in arid land, a two factorial manipulation experiment in the shrubland of an arid region in northwest China was conducted. The experiment used a nested design with fresh organic matter and water as the two controlled parameters. It was found that both fresh organic matter and water enhanced soil respiration, and there was a synergistic effect of these two treatments on soil respiration increase. Water addition not only enhanced soil C emission, but also regulated soil C sequestration by fresh organic matter addition. The results indicated that the soil CO2 flux of the shrubland is likely to increase with climate change, and precipitation played a dominant role in regulating soil C balance in the shrubland of an arid region. PMID:24204907

  2. Volcanic monitoring techniques applied to controlled fragmentation experiments

    NASA Astrophysics Data System (ADS)

    Kueppers, Ulrich; Alatorre-Ibarguengoitia, Miguel; Hort, Matthias; Kremers, Simon; Meier, Kristina; Scharff, Lea; Scheu, Bettina; Taddeucci, Jacopo; Dingwell, Donald B.

    2010-05-01

    A rapidly growing number of people is threatened by natural hazards such as volcanic eruptions, earthquakes, floods, or storms. Volcanic eruptions not only have an impact on their direct neighbourhood but may also affect aviation, infrastructure and climate, regionally as well as globally. In respect to several other natural threats, volcanoes exhibit the advantage of a usually known location of the pending threat, allowing the deployment of sophisticated monitoring networks. Such networks deliver information about volcanic systems and the correct interpretation of monitoring data is a viable key to a successful hazard mitigation strategy. Today a large number of volcanoes is equipped with a variety of scientific instruments that help elucidate the secrets of volcanic phenomena. However, our mechanistic understanding of the processes behind recorded signals or a solid interpretation of the state of a volcano is poor. Experimental volcanology is a chief source of mechanistic understanding of volcanic systems. Here, we bring volcanic monitoring and experimental volcanology together in a campaign of well-monitored, field-based, experimental volcanology. We present results from a multi-parametric combination of well-controlled experiments and several tools commonly used for monitoring active volcanoes. We performed rapid decompression experiments with natural rock samples from Colima volcano (Mexico) to simulate explosive volcanic eruptions. We used 2 sample varieties of approx. 25 and 35 vol.% open porosity. Sample size was 60 mm height and 25 mm and 60 mm diameter, respectively. Applied pressure ranges from 4 to 18 MPa. The pressurised volume above the samples ranges from 60 - 170 cm³. The experiments have been thoroughly monitored with 1) Doppler-Radar, 2) High-speed and video camera, 3) acoustic and infrasonic sensors, 4) pressure transducers, and 5) electrically conducting wires to shed light on fragmentation, ejection, and ejection speed of volcanic pyroclasts

  3. [Critical of the additive model of the randomized controlled trial].

    PubMed

    Boussageon, Rémy; Gueyffier, François; Bejan-Angoulvant, Theodora; Felden-Dominiak, Géraldine

    2008-01-01

    Randomized, double-blind, placebo-controlled clinical trials are currently the best way to demonstrate the clinical effectiveness of drugs. Its methodology relies on the method of difference (John Stuart Mill), through which the observed difference between two groups (drug vs placebo) can be attributed to the pharmacological effect of the drug being tested. However, this additive model can be questioned in the event of statistical interactions between the pharmacological and the placebo effects. Evidence in different domains has shown that the placebo effect can influence the effect of the active principle. This article evaluates the methodological, clinical and epistemological consequences of this phenomenon. Topics treated include extrapolating results, accounting for heterogeneous results, demonstrating the existence of several factors in the placebo effect, the necessity to take these factors into account for given symptoms or pathologies, as well as the problem of the "specific" effect.

  4. LabVIEW-based control and data acquisition system for cathodoluminescence experiments.

    PubMed

    Bok, J; Schauer, P

    2011-11-01

    Computer automation of cathodoluminescence (CL) experiments using equipment developed in our laboratory is described. The equipment provides various experiments for CL efficiency, CL spectra, and CL time response studies. The automation was realized utilizing the graphical programming environment LabVIEW. The developed application software with procedures for equipment control and data acquisition during various CL experiments is presented. As the measured CL data are distorted by technical limitations of the equipment, such as equipment spectral sensitivity and time response, data correction algorithms were incorporated into the procedures. Some examples of measured data corrections are presented. © 2011 American Institute of Physics

  5. Data Assimilation Experiments using Quality Controlled AIRS Version 5 Temperature Soundings

    NASA Technical Reports Server (NTRS)

    Susskind, Joel

    2008-01-01

    The AIRS Science Team Version 5 retrieval algorithm has been finalized and is now operational at the Goddard DAAC in the processing (and reprocessing) of all AlRS data. Version 5 contains accurate case-by-case error estimates for most derived products, which are also used for quality control. We have conducted forecast impact experiments assimilating AlRS quality controlled temperature profiles using the NASA GEOS-5 data assimilation system, consisting of the NCEP GSI analysis coupled with the NASA FVGCM. Assimilation of quality controlled temperature profiles resulted in significantly improved forecast skill in both the Northern Hemisphere and Southern Hemisphere Extra-Tropics, compared to that obtained from analyses obtained when all data used operationally by NCEP except for AlRS data is assimilated. Experiments using different Quality Control thresholds for assimilation of AlRS temperature retrievals showed that a medium quality control threshold performed better than a tighter threshold, which provided better overall sounding accuracy; or a looser threshold, which provided better spatial coverage of accepted soundings. We are conducting more experiments to further optimize this balance of spatial coverage and sounding accuracy from the data assimilation perspective. In all cases, temperature soundings were assimilated well below cloud level in partially cloudy cases. The positive impact of assimilating AlRS derived atmospheric temperatures all but vanished when only AIRS stratospheric temperatures were assimilated. Forecast skill resulting from assimilation of AlRS radiances uncontaminated by clouds, instead of AlRS temperature soundings, was only slightly better than that resulting from assimilation of only stratospheric AlRS temperatures. This reduction in forecast skill is most likely the result of significant loss of tropospheric information when only AIRS radiances unaffected by clouds are used in the data assimilation process.

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

    ERIC Educational Resources Information Center

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

    2014-01-01

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

  7. Pennsylvania's experiences with microbial control of the gypsy moth

    Treesearch

    James O. Nichols

    1985-01-01

    Pennsylvania's first experience with using Bt on insect control occurred in 1964. For the next 17 years, various projects were conducted, in cooperation with the USFS and industry, in an effort to secure operational status of Bt for gypsy moth suppression. This point was reached in 1982, and the Governor was convinced that the time was right to convert most gypsy...

  8. Macro-/Micro-Controlled 3D Lithium-Ion Batteries via Additive Manufacturing and Electric Field Processing.

    PubMed

    Li, Jie; Liang, Xinhua; Liou, Frank; Park, Jonghyun

    2018-01-30

    This paper presents a new concept for making battery electrodes that can simultaneously control macro-/micro-structures and help address current energy storage technology gaps and future energy storage requirements. Modern batteries are fabricated in the form of laminated structures that are composed of randomly mixed constituent materials. This randomness in conventional methods can provide a possibility of developing new breakthrough processing techniques to build well-organized structures that can improve battery performance. In the proposed processing, an electric field (EF) controls the microstructures of manganese-based electrodes, while additive manufacturing controls macro-3D structures and the integration of both scales. The synergistic control of micro-/macro-structures is a novel concept in energy material processing that has considerable potential for providing unprecedented control of electrode structures, thereby enhancing performance. Electrochemical tests have shown that these new electrodes exhibit superior performance in their specific capacity, areal capacity, and life cycle.

  9. Psychological impact of screening for type 2 diabetes: controlled trial and comparative study embedded in the ADDITION (Cambridge) randomised controlled trial.

    PubMed

    Eborall, Helen C; Griffin, Simon J; Prevost, A Toby; Kinmonth, Ann-Louise; French, David P; Sutton, Stephen

    2007-09-08

    To quantify the psychological impact of primary care based stepwise screening for type 2 diabetes. Controlled trial and comparative study embedded in a randomised controlled trial. 15 practices (10 screening, five control) in the ADDITION (Cambridge) trial in the east of England. 7380 adults (aged 40-69) in the top fourth for risk of having undiagnosed type 2 diabetes (6416 invited for screening, 964 controls). Invited for screening for type 2 diabetes or not invited (controls), incorporating a comparative study of subgroups of screening attenders. Attenders completed questionnaires after a random blood glucose test and at 3-6 months and 12-15 months later. Controls were sent questionnaires at corresponding time points. Non-attenders were sent questionnaires at 3-6 months and 12-15 months. State anxiety (Spielberger state anxiety inventory), anxiety and depression (hospital anxiety and depression scale), worry about diabetes, and self rated health. No significant differences were found between the screening and control participants at any time-for example, difference in means (95% confidence intervals) for state anxiety after the initial blood glucose test was -0.53, -2.60 to 1.54, at 3-6 months was 1.51 (-0.17 to 3.20), and at 12-15 months was 0.57, -1.11 to 2.24. After the initial test, compared with participants who screened negative, those who screened positive reported significantly poorer general health (difference in means -0.19, -0.25 to -0.13), higher state anxiety (0.93, -0.02 to 1.88), higher depression (0.32, 0.08 to 0.56), and higher worry about diabetes (0.25, 0.09 to 0.41), although effect sizes were small. Small but significant trends were found for self rated health across the screening subgroups at 3-6 months (P=0.047) and for worry about diabetes across the screen negative groups at 3-6 months and 12-15 months (P=0.001). Screening for type 2 diabetes has limited psychological impact on patients. Implementing a national screening programme based

  10. Real Time Control of CO2 Enrichment Experiments on the Sea Floor Enabled by the MARS Cabled Observatory

    NASA Astrophysics Data System (ADS)

    Brewer, P. G.; Mbari Foce Team

    2010-12-01

    We report on progress on FOCE (Free Ocean CO2 Enrichment) techniques designed to accomplish realistic (that is not contained within land-based aquaria) experiments on the response of deep-sea animals and biogeochemical cycles to ocean acidification. Such experiments have long been carried out on ecosystems on land, and the outcome has differed significantly from CO2 enrichment in enclosed greenhouse systems, thereby undoing much of the hope for an increase in the large-scale biosphere draw down of atmospheric CO2. It is a far bigger step if deep-sea animals and systems are removed from their cold, dark, high pressure and low oxygen native habitat. The equivalent problem in the ocean is far more difficult because of (1) the very different physical forcing; (2) the complex reaction rates between CO2 and water require delay times between addition and entry to the experimental space; (3) the lack of supporting infrastructure and of adequate sensors; and (4) the need for sophisticated and robust control techniques in both hardware and software. We have overcome almost all of these challenges, and related working systems have already been successfully deployed on the Great Barrier Reef coralline flats with Australian colleagues. We have used the MBARI MARS (Monterey Accelerated Research System) cabled observatory to carry out deep-ocean (880m depth) experiments. The basic experimental unit is a 1m x 1m x 50cm chamber with side arms of ~ 3m length to provide the required chemical delay times for the reaction between admixed CO2 enriched sea water and emergence of the flow into the main chamber. Controllable thrusters, operated by user commands, help maintain a steady flow of seawater through the experiment. The site is slightly below the depth of the O2 minimum where small changes in either O2 from ocean warming, or CO2 from ocean acidification can lead to the formation of dead zones. Shallow (near shore) experiments are now also in the late planning stages. We have

  11. Versatile controllability of non-axisymmetric magnetic perturbations in KSTAR experiments

    NASA Astrophysics Data System (ADS)

    Han, Hyunsun; Jeon, Y. M.; in, Y.; Kim, J.; Yoon, S. W.; Hahn, S. H.; Ahn, H. S.; Woo, M. H.; Park, B. H.; Bak, J. G.; Kstar Team

    2015-11-01

    A newly upgraded IVCC (In-Vessel Control Coil) system equipped with four broadband power supplies, along with current connection patch panel, will be presented and discussed in terms of its capability on various KSTAR experiments. Until the last run-campaign, there were impressive experimental results on ELM(Edge Localized Mode) control experiments using the 3D magnetic field, but the non-axisymmetric field configuration could not be changed in a shot, let alone the limited number of accessible configurations. Introducing the new power supplies, such restrictions have been greatly reduced. Based on the preliminary commissioning results for 2015 KSTAR run-campaign, this new system has been confirmed to easily cope with various dynamic demands for toroidal and poloidal phases of 3D magnetic field in a shot. This enables us to diagnose the plasma response in more detail and to address the 3-D field impacts on the ELM behaviors better than ever.

  12. Determination of Unknown Concentrations of Sodium Acetate Using the Method of Standard Addition and Proton NMR: An Experiment for the Undergraduate Analytical Chemistry Laboratory

    ERIC Educational Resources Information Center

    Rajabzadeh, Massy

    2012-01-01

    In this experiment, students learn how to find the unknown concentration of sodium acetate using both the graphical treatment of standard addition and the standard addition equation. In the graphical treatment of standard addition, the peak area of the methyl peak in each of the sodium acetate standard solutions is found by integration using…

  13. A novel control software that improves the experimental workflow of scanning photostimulation experiments.

    PubMed

    Bendels, Michael H K; Beed, Prateep; Leibold, Christian; Schmitz, Dietmar; Johenning, Friedrich W

    2008-10-30

    Optical uncaging of caged compounds is a well-established method to study the functional anatomy of a brain region on the circuit level. We present an alternative approach to existing experimental setups. Using a low-magnification objective we acquire images for planning the spatial patterns of stimulation. Then high-magnification objectives are used during laser stimulation providing a laser spot between 2 microm and 20 microm size. The core of this system is a video-based control software that monitors and controls the connected devices, allows for planning of the experiment, coordinates the stimulation process and manages automatic data storage. This combines a high-resolution analysis of neuronal circuits with flexible and efficient online planning and execution of a grid of spatial stimulation patterns on a larger scale. The software offers special optical features that enable the system to achieve a maximum degree of spatial reliability. The hardware is mainly built upon standard laboratory devices and thus ideally suited to cost-effectively complement existing electrophysiological setups with a minimal amount of additional equipment. Finally, we demonstrate the performance of the system by mapping the excitatory and inhibitory connections of entorhinal cortex layer II stellate neurons and present an approach for the analysis of photo-induced synaptic responses in high spontaneous activity.

  14. Software reliability: Additional investigations into modeling with replicated experiments

    NASA Technical Reports Server (NTRS)

    Nagel, P. M.; Schotz, F. M.; Skirvan, J. A.

    1984-01-01

    The effects of programmer experience level, different program usage distributions, and programming languages are explored. All these factors affect performance, and some tentative relational hypotheses are presented. An analytic framework for replicated and non-replicated (traditional) software experiments is presented. A method of obtaining an upper bound on the error rate of the next error is proposed. The method was validated empirically by comparing forecasts with actual data. In all 14 cases the bound exceeded the observed parameter, albeit somewhat conservatively. Two other forecasting methods are proposed and compared to observed results. Although demonstrated relative to this framework that stages are neither independent nor exponentially distributed, empirical estimates show that the exponential assumption is nearly valid for all but the extreme tails of the distribution. Except for the dependence in the stage probabilities, Cox's model approximates to a degree what is being observed.

  15. Functional electrical stimulation controlled by artificial neural networks: pilot experiments with simple movements are promising for rehabilitation applications.

    PubMed

    Ferrante, Simona; Pedrocchi, Alessandra; Iannò, Marco; De Momi, Elena; Ferrarin, Maurizio; Ferrigno, Giancarlo

    2004-01-01

    This study falls within the ambit of research on functional electrical stimulation for the design of rehabilitation training for spinal cord injured patients. In this context, a crucial issue is the control of the stimulation parameters in order to optimize the patterns of muscle activation and to increase the duration of the exercises. An adaptive control system (NEURADAPT) based on artificial neural networks (ANNs) was developed to control the knee joint in accordance with desired trajectories by stimulating quadriceps muscles. This strategy includes an inverse neural model of the stimulated limb in the feedforward line and a neural network trained on-line in the feedback loop. NEURADAPT was compared with a linear closed-loop proportional integrative derivative (PID) controller and with a model-based neural controller (NEUROPID). Experiments on two subjects (one healthy and one paraplegic) show the good performance of NEURADAPT, which is able to reduce the time lag introduced by the PID controller. In addition, control systems based on ANN techniques do not require complicated calibration procedures at the beginning of each experimental session. After the initial learning phase, the ANN, thanks to its generalization capacity, is able to cope with a certain range of variability of skeletal muscle properties.

  16. Women's experiences as members of attention control and experimental intervention groups in a randomized controlled trial.

    PubMed

    Beal, Claudia C; Stuifbergen, Alexa; Volker, Deborah; Becker, Heather

    2009-12-01

    Attention control groups are often used in research testing the efficacy of psychosocial and behavioural interventions in order to control for placebo effects. The authors conducted a descriptive qualitative study to investigate how participants viewed their experiences in attention control and experimental intervention groups following a randomized controlled trial for women with fibromyalgia syndrome. Moderately structured interviews were conducted with 18 women (12 from the experimental intervention group and 6 from the attention control group). Members of the control group reported some benefits but few behavioural changes as a result of participating in the RCT, and some participants expressed disappointment at not receiving the intervention. Perceptions of changes in attitudes towards fibromyalgia syndrome and behaviours reported by the intervention group appear to be consistent with the theory underlying the intervention. Possible placebo effects identified in both groups include negative and positive social interactions with other participants.

  17. The National Advisory Committee on Hyperkinesis and Food Additives. Report to the Nutrition Foundation.

    ERIC Educational Resources Information Center

    National Advisory Committee on Hyperkinesis and Food Additives.

    Reviewed in the report is research on hyperkinesis, specifically B. Feingold's hypotheses on the role of salicylates and food additives. Criticisms of Feingold's studies are seen to include methodological weaknesses (no double blind controlled experiments), nutritional concerns over the adequacy of prescribed diets, and lack of a specifically…

  18. Can virtual nature improve patient experiences and memories of dental treatment? A study protocol for a randomized controlled trial.

    PubMed

    Tanja-Dijkstra, Karin; Pahl, Sabine; White, Mathew P; Andrade, Jackie; May, Jon; Stone, Robert J; Bruce, Malcolm; Mills, Ian; Auvray, Melissa; Gabe, Rhys; Moles, David R

    2014-03-22

    Dental anxiety and anxiety-related avoidance of dental care create significant problems for patients and the dental profession. Distraction interventions are used in daily medical practice to help patients cope with unpleasant procedures. There is evidence that exposure to natural scenery is beneficial for patients and that the use of virtual reality (VR) distraction is more effective than other distraction interventions, such as watching television. The main aim of this randomized controlled trial is to determine whether the use of VR during dental treatment can improve the overall dental experience and recollections of treatment for patients, breaking the negative cycle of memories of anxiety leading to further anxiety, and avoidance of future dental appointments. Additionally, the aim is to test whether VR benefits dental patients with all levels of dental anxiety or whether it could be especially beneficial for patients suffering from higher levels of dental anxiety. The third aim is to test whether the content of the VR distraction can make a difference for its effectiveness by comparing two types of virtual environments, a natural environment and an urban environment. The effectiveness of VR distraction will be examined in patients 18 years or older who are scheduled to undergo dental treatment for fillings and/or extractions, with a maximum length of 30 minutes. Patients will be randomly allocated into one of three groups. The first group will be exposed to a VR of a natural environment. The second group will be exposed to a VR of an urban environment. A third group consists of patients who receive standard care (control group). Primary outcomes relate to patients' memories of the dental treatment one week after treatment: (a) remembered pain, (b) intrusive thoughts and (c) vividness of memories. Other measures of interest are the dental experience, the treatment experience and the VR experience. Current Controlled Trials ISRCTN41442806.

  19. Controlled challenge experiment demonstrates substantial additive genetic variation in resistance of Nile tilapia (Oreochromis niloticus) to Streptococcus iniae

    USDA-ARS?s Scientific Manuscript database

    Streptococcus iniae is an etiologic agent of streptococcal disease in tilapia and is one of several Streptococcus spp. that negatively impact worldwide tilapia production. Methods for the prevention and control of S. iniae include vaccines, management strategies, and antibiotics. A complimentary pre...

  20. An experiment in software reliability: Additional analyses using data from automated replications

    NASA Technical Reports Server (NTRS)

    Dunham, Janet R.; Lauterbach, Linda A.

    1988-01-01

    A study undertaken to collect software error data of laboratory quality for use in the development of credible methods for predicting the reliability of software used in life-critical applications is summarized. The software error data reported were acquired through automated repetitive run testing of three independent implementations of a launch interceptor condition module of a radar tracking problem. The results are based on 100 test applications to accumulate a sufficient sample size for error rate estimation. The data collected is used to confirm the results of two Boeing studies reported in NASA-CR-165836 Software Reliability: Repetitive Run Experimentation and Modeling, and NASA-CR-172378 Software Reliability: Additional Investigations into Modeling With Replicated Experiments, respectively. That is, the results confirm the log-linear pattern of software error rates and reject the hypothesis of equal error rates per individual fault. This rejection casts doubt on the assumption that the program's failure rate is a constant multiple of the number of residual bugs; an assumption which underlies some of the current models of software reliability. data raises new questions concerning the phenomenon of interacting faults.

  1. Stratospheric controlled perturbation experiment (SCoPEx): overview, status, and results from related laboratory experiments

    NASA Astrophysics Data System (ADS)

    Keith, D.; Dykema, J. A.; Keutsch, F. N.

    2017-12-01

    Stratospheric Controlled Perturbation Experiment (SCoPEx), is a scientific experiment to advance understanding of stratospheric aerosols. It aims to make quantitative measurements of aerosol microphysics and atmospheric chemistry to improve large-scale models used to assess the risks and benefits of solar geoengineering. A perturbative experiment requires: (a) means to create a well-mixed, small perturbed volume, and (b) observation of time evolution of chemistry and aerosols in the volume. SCoPEx will used a propelled balloon gondola containing all instruments and drive system. The propeller wake forms a well-mixed volume (roughly 1 km long and 100 meters in diameter) that serves as an experimental `beaker' into which aerosols (e.g., < 1 kg of 0.3 µm radius CaCO3 particles) at can be injected; while, the propellers allow the gondola to move at speeds up to 3 m/sec relative to the local air mass driving the gondola back forth through the volume to measure properties of the perturbed air mass. This presentation will provide an overview of the experiment including (a) a systems engineering perspective from high-level scientific questions through instrument selection, mission design, and proposed operations and data analysis; (b) instruments, include current status of integration testing; (c) payload engineering including structure, power and mass budget, etc; (d) results from CFD simulation of propeller wake and simulation of chemistry and aerosol microphysics; and finally (e) proposed concept of operations and schedule. We will also provide an overview of the plans for governance including management of health safety and environmental risks, transparency, public engagement, and larger questions about governance of solar geoengineering experiments. Finally, we will briefly present results of laboratory experiments of the interaction of chemical such as ClONO2 and HCl on particle surfaces relevant for stratospheric solar geoengineering.

  2. Coper Isotope Fractionation in Porphyry Copper Deposits: A Controlled Experiment

    NASA Astrophysics Data System (ADS)

    Ruiz, J.; Mathur, R.; Uhrie, J. L.; Hiskey, B.

    2001-12-01

    Previous studies have shown that copper is fractionated in the environment. However, the mechanisms for isotope fractionation and the role of organic and inorganic processes in the fractionation are not well understood. Here we used the well controlled experiments used by Phelps Dodge Corporation aimed at leaching copper from their ore deposits to constrain the mechanism of copper isotope fractionation in natural systems. The isotope data were collected on a Micromass Isoprobe. High temperature copper sulfides from ore deposits in Chile and Arizona yield delta 65Cu near 0 permil. The reproducibility of the data is better that 0.1 permil. Controlled experiments consisting of large columns of rocks were fed solutions containing bacteria such as Thiobacillus ferroxidans and Leptospirrilium ferroxidan. Solutions fom the columns were sampled for sixty days and analyzed for copper concentrations, oxidation potential, ferrous/ferric ratios and pH. The results indicate that the bacterially aided dissolution of copper fractionated copper. Preliminary experiments of copper dissolution not using bacteria show no isotope fractionation The original rock in the experiment has a delta 65Cu of -2.1. The first solutions that were collected from the columns had a delta 65Cu of -5.0 per mil. The liquid changed its isotopic composition from -50 to -10 during the sixty days of sampling. The greatest shift in the isotope ratios occurred the first 30 days when the copper recovered was less than 40% and the ferrous/ferric ratios were somewhat constant. At approximately 35 days after the start of the experiments, the copper recovery increases the ferrousferric ratio decreased and the copper isotope ratio of the fluids remained fairly constant. The data suggest that the bacteria are required to effectively fractionate copper isotopes in natural systems and that the mechanisms of bacterial aided copper dissolution may include a direct dissolution of the sulfides by the bacteria. Experiments

  3. Implementation of statistical process control for proteomic experiments via LC MS/MS.

    PubMed

    Bereman, Michael S; Johnson, Richard; Bollinger, James; Boss, Yuval; Shulman, Nick; MacLean, Brendan; Hoofnagle, Andrew N; MacCoss, Michael J

    2014-04-01

    Statistical process control (SPC) is a robust set of tools that aids in the visualization, detection, and identification of assignable causes of variation in any process that creates products, services, or information. A tool has been developed termed Statistical Process Control in Proteomics (SProCoP) which implements aspects of SPC (e.g., control charts and Pareto analysis) into the Skyline proteomics software. It monitors five quality control metrics in a shotgun or targeted proteomic workflow. None of these metrics require peptide identification. The source code, written in the R statistical language, runs directly from the Skyline interface, which supports the use of raw data files from several of the mass spectrometry vendors. It provides real time evaluation of the chromatographic performance (e.g., retention time reproducibility, peak asymmetry, and resolution), and mass spectrometric performance (targeted peptide ion intensity and mass measurement accuracy for high resolving power instruments) via control charts. Thresholds are experiment- and instrument-specific and are determined empirically from user-defined quality control standards that enable the separation of random noise and systematic error. Finally, Pareto analysis provides a summary of performance metrics and guides the user to metrics with high variance. The utility of these charts to evaluate proteomic experiments is illustrated in two case studies.

  4. Exposure of Polymer Film Thermal Control Materials on the Materials International Space Station Experiment (MISSE)

    NASA Technical Reports Server (NTRS)

    Dever, Joyce; Miller, Sharon; Messer, Russell; Sechkar, Edward; Tollis, Greg

    2002-01-01

    Seventy-nine samples of polymer film thermal control (PFTC) materials have been provided by the National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) for exposure to the low Earth orbit environment on the exterior of the International Space Station (ISS) as part of the Materials International Space Station Experiment (MISSE). MISSE is a materials flight experiment sponsored by the Air Force Research Lab/Materials Lab and NASA. This paper will describe background, objectives, and configurations for the GRC PFTC samples for MISSE. These samples include polyimides, fluorinated polyimides, and Teflon fluorinated ethylene propylene (FEP) with and without second-surface metallizing layers and/or surface coatings. Also included are polyphenylene benzobisoxazole (PBO) and a polyarylene ether benzimidazole (TOR-LM). On August 16, 2001, astronauts installed passive experiment carriers (PECs) on the exterior of the ISS in which were located twenty-eight of the GRC PFTC samples for 1-year space exposure. MISSE PECs for 3-year exposure, which will contain fifty-one GRC PFTC samples, will be installed on the ISS at a later date. Once returned from the ISS, MISSE GRC PFTC samples will be examined for changes in optical and mechanical properties and atomic oxygen (AO) erosion. Additional sapphire witness samples located on the AO exposed trays will be examined for deposition of contaminants.

  5. Birth control sabotage and forced sex: experiences reported by women in domestic violence shelters.

    PubMed

    Thiel de Bocanegra, Heike; Rostovtseva, Daria P; Khera, Satin; Godhwani, Nita

    2010-05-01

    Women who experience intimate partner violence often experience birth control sabotage, forced sex, and partner's unwillingness to use condoms. We interviewed 53 women at four domestic violence shelters. Participants reported that their abusive partners frequently refused to use condoms, impeded them from accessing health care, and subjected them to birth control sabotage, infidelity, and forced sex. However, women also reported strategies to counteract these actions, particularly against birth control sabotage and attempts to force them to abort or continue a pregnancy. Domestic violence counselors can focus on these successful strategies to validate coping skills and build self-esteem.

  6. LDR structural experiment definition

    NASA Technical Reports Server (NTRS)

    Russell, R. A.

    1988-01-01

    A system study to develop the definition of a structural flight experiment for a large precision segmented reflector on the Space Station was accomplished by the Boeing Aerospace Company for NASA's Langley Research Center. The objective of the study was to use a Large Deployable Reflector (LDR) baseline configuration as the basis for focusing an experiment definition, so that the resulting accommodation requirements and interface constraints could be used as part of the mission requirements data base for Space Station. The primary objectives of the first experiment are to construct the primary mirror support truss and to determine its structural and thermal characteristics. Addition of an optical bench, thermal shield and primary mirror segments, and alignment of the optical components, would occur on a second experiment. The structure would then be moved to the payload point system for pointing, optical control, and scientific optical measurement for a third experiment. Experiment 1 will deploy the primary support truss while it is attached to the instrument module structure. The ability to adjust the mirror attachment points and to attach several dummy primary mirror segments with a robotic system will also be demonstrated. Experiment 2 will be achieved by adding new components and equipment to experiment one. Experiment 3 will demonstrate advanced control strategies, active adjustment of the primary mirror alignment, and technologies associated with optical sensing.

  7. Effects of personal experiences on the interpretation of the meaning of colours used in the displays and controls in electric control panels.

    PubMed

    Lee, Inseok; Hwang, Won-Gue

    2015-01-01

    A survey was conducted to examine how personal experiences affect the interpretation of the meaning of display and control colours on electric control panels (ECPs). In Korea, the red light on ECPs represents a normal state of operation, while the green light represents a stopped state of operation; this appears to contradict the general stereotypes surrounding these colours. The survey results indicated that the participants who had experience in using ECPs interpreted the colour meaning differently from the other participant group. More than half of the experienced participants regarded the coloured displays and controls as they were designed, while most participants in the other group appeared to interpret the colours in accordance with the stereotypes. It is presumed that accidents related to human errors can occur when non-experienced people use the ECPs, which are easily accessible in many buildings. Practitioner Summary: A survey was conducted to investigate how personal experiences affect the interpretation of the function meanings of coloured lights on electrical control panels. It was found that the interpretation varies according to personal experiences, which can induce accidents related to human errors while operating electrical equipment.

  8. Tank Pressure Control Experiment: Thermal Phenomena in Microgravity. Video 3 of 4

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The report presents the results of the flight experiment Tank Pressure Control Experiment/Thermal Phenomena (TPCE/TP) performed in the microgravity environment of the space shuttle. TPCE/TP, flown on the Space Transportation System STS-52, was a second flight of the Tank Pressure Control Experiment (TPCE). The experiment used Freon 113 at near saturation conditions. The test tank was filled with liquid to about 83 percent by volume. The experiment consisted of 21 tests. Each test generally started with a heating phase to increase the tank pressure and to develop temperature stratification in the fluid, followed by a fluid mixing phase for the tank pressure reduction and fluid temperature equilibration. The heating phase provided pool boiling data from large (relative to bubble sizes) heating surfaces (0.1046 m by 0.0742 m) at low heat fluxes (0.23 to 1.16 kW/m(exp 2)). The system pressure and the bulk liquid subcooling varied from 39 to 78 kPa and 1 to 3 deg C, respectively. The boiling process during the entire heating period, as well a jet-induced mixing process for the first 2 min. of the mixing period, was also recorded on video. Analyses of data from the two flight experiments (TPCE and TPCE/TP) and their comparison with the results obtained in drop tower experiments suggest that as Bond number approaches zero the flow pattern produced by an axial jet and the mixing time can be predicted by the Weber number. This is video 3 of 4.

  9. Tank Pressure Control Experiment: Thermal Phenomena in Microgravity. Video 4 of 4

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The report presents the results of the flight experiment Tank Pressure Control Experiment/Thermal Phenomena (TPCE/TP) performed in the microgravity environment of the space shuttle. TPCE/TP, flown on the Space Transportation System STS-52, was a second flight of the Tank Pressure Control Experiment (TPCE). The experiment used Freon 113 at near saturation conditions. The test tank was filled with liquid to about 83 percent by volume. The experiment consisted of 21 tests. Each test generally started with a heating phase to increase the tank pressure and to develop temperature stratification in the fluid, followed by a fluid mixing phase for the tank pressure reduction and fluid temperature equilibration. The heating phase provided pool boiling data from large (relative to bubble sizes) heating surfaces (0.1046 m by 0.0742 m) at low heat fluxes (0.23 to 1.16 kW/m(exp 2)). The system pressure and the bulk liquid subcooling varied from 39 to 78 kPa and 1 to 3 deg C, respectively. The boiling process during the entire heating period, as well a jet-induced mixing process for the first 2 min. of the mixing period, was also recorded on video. Analyses of data from the two flight experiments (TPCE and TPCE/TP) and their comparison with the results obtained in drop tower experiments suggest that as Bond number approaches zero the flow pattern produced by an axial jet and the mixing time can be predicted by the Weber number. This is video 4 of 4.

  10. Tank Pressure Control Experiment: Thermal Phenomena in Microgravity. Video 1 of 4

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The report presents the results of the flight experiment Tank Pressure Control Experiment/Thermal Phenomena (TPCE/TP) performed in the microgravity environment of the space shuttle. TPCE/TP, flown on the Space Transportation System STS-52, was a second flight of the Tank Pressure Control Experiment (TPCE). The experiment used Freon 113 at near saturation conditions. The test tank was filled with liquid to about 83 percent by volume. The experiment consisted of 21 tests. Each test generally started with a heating phase to increase the tank pressure and to develop temperature stratification in the fluid, followed by a fluid mixing phase for the tank pressure reduction and fluid temperature equilibration. The heating phase provided pool boiling data from large (relative to bubble sizes) heating surfaces (0.1046 m by 0.0742 m) at low heat fluxes (0.23 to 1.16 kW/m(exp 2)). The system pressure and the bulk liquid subcooling varied from 39 to 78 kPa and 1 to 3 deg C, respectively. The boiling process during the entire heating period, as well a jet-induced mixing process for the first 2 min. of the mixing period, was also recorded on video. Analyses of data from the two flight experiments (TPCE and TPCE/TP) and their comparison with the results obtained in drop tower experiments suggest that as Bond number approaches zero the flow pattern produced by an axial jet and the mixing time can be predicted by the Weber number. This is video 1 of 4.

  11. Tank Pressure Control Experiment: Thermal Phenomena in Microgravity. Video 2 of 4

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The report presents the results of the flight experiment Tank Pressure Control Experiment/Thermal Phenomena (TPCE/TP) performed in the microgravity environment of the space shuttle. TPCE/TP, flown on the Space Transportation System STS-52, was a second flight of the Tank Pressure Control Experiment (TPCE). The experiment used Freon 113 at near saturation conditions. The test tank was filled with liquid to about 83 percent by volume. The experiment consisted of 21 tests. Each test generally started with a heating phase to increase the tank pressure and to develop temperature stratification in the fluid, followed by a fluid mixing phase for the tank pressure reduction and fluid temperature equilibration. The heating phase provided pool boiling data from large (relative to bubble sizes) heating surfaces (0.1046 m by 0.0742 m) at low heat fluxes (0.23 to 1.16 kW/m(exp 2)). The system pressure and the bulk liquid subcooling varied from 39 to 78 kPa and 1 to 3 deg C, respectively. The boiling process during the entire heating period, as well a jet-induced mixing process for the first 2 min. of the mixing period, was also recorded on video. Analyses of data from the two flight experiments (TPCE and TPCE/TP) and their comparison with the results obtained in drop tower experiments suggest that as Bond number approaches zero the flow pattern produced by an axial jet and the mixing time can be predicted by the Weber number. This is video 2 of 4.

  12. Does Provider Self-Reporting of Etiquette Behaviors Improve Patient Experience? A Randomized Controlled Trial.

    PubMed

    Siddiqui, Zishan; Qayyum, Rehan; Bertram, Amanda; Durkin, Nowella; Kebede, Sosena; Ponor, Lucia; Oduyebo, Ibironke; Allen, Lisa; Brotman, Daniel J

    2017-06-01

    There is a glaring lack of published evidence-based strategies to improve the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) patient experience scores on the physician domain. Strategies that have been used are resource intensive and difficult to sustain. We hypothesized that prompting providers to assess their own etiquette-based practices every 2 weeks over the course of 1 year would improve patient experience on the physician domain. Randomized controlled trial. 4 acute care hospitals. Hospitalists. Hospitalists were randomized to the study or the control arm. The study arm was prompted every 2 weeks for 12 months to report how frequently they engaged in 7 best-practice bedside etiquette behaviors. Control arm participants received similarly worded questions on quality improvement behaviors. Provider experience scores were calculated from the physician HCAHPS and Press Ganey survey provider items. Physicians reported high rates of etiquette-based behavior at baseline, and this changed modestly over the study period. Self-reported etiquette behaviors were not associated with experience scores. The difference in difference analysis of the baseline and postintervention physician experience scores between the intervention arm and the control arm was not statistically significant (P = 0.71). In this 12-month study, biweekly reflection and reporting of best-practice bedside etiquette behaviors did not result in significant improvement on physician domain experience scores. It is likely that hospitalists' self-assessment of their bedside etiquette may not reflect patient perception of these behaviors. Furthermore, hospitalists may be resistant to improvement in this area since they rate themselves highly at baseline. Journal of Hospital Medicine 2017;12:402-406. © 2017 Society of Hospital Medicine

  13. Development of Control Teaching Material for Mechatronics Education Based on Experience

    NASA Astrophysics Data System (ADS)

    Tasaki, Takao; Watanabe, Shinichi; Shikanai, Yoshihito; Ozaki, Koichi

    In this paper, we have developed a teaching material for technical high school students to understand the control technique. The material makes the students understanding the control technique through the sensibility obtained from the experience of riding the robot. We have considered the correspondence of the teaching material with the ARCS Model. Therefore, the material aims to improve the interest and the willingness to learn mechatronics and control technique by experiencing the difference of the response by the change in the control parameters. As the results of the questionnaire to the technical high school students in the class, we have verified educative effect of the teaching material which can be improved willingness of learning and interesting for mechatronics and control technique.

  14. Thermoelectric Converter for Loop Heat Pipe Temperature Control: Experience and Lessons Learned

    NASA Technical Reports Server (NTRS)

    Ku, Jentung; Ottenstein, Laura

    2010-01-01

    This paper describes the theoretical background and implementation methodology of using a thermoelectric converter (TEC) for operating temperature control of a loop heat pipe (LHP). In particular, experimental results from ambient and thermal vacuum tests of an LHP are presented for illustrations. The most commonly used state-of-the-art method to control the LHP operating temperature is to cold bias its compensation chamber (CC) and use an electrical heater to maintain the CC at the desired set point temperature. Although effective, this approach has its shortcomings in that the electrical heater can only provide heating to the CC, and the required power can be large under certain conditions. An alternative method is to use a TEC, which is capable of providing both heating and cooling to the CC. In this method, one side of the TEC is attached to the CC, and the other side is connected to the evaporator via a thermal strap. Using a bipolar power supply and a control algorithm, a TEC can function as a heater or a cooler, depending on the direction of the current flow. Extensive ground tests of several LHPs have demonstrated that a TEC can provide very tight temperature control for the CC. It also offers several additional advantages: (1) The LHP can operate at temperatures below its natural operating temperature at low heat loads; (2) The required heater power for a TEC is much less than that for an electrical heater; and (3) It enhances the LHP start-up success. Although the concept of using a TEC for LHP temperature control is simple, there are many factors to be considered in its implementation for space applications because the TEC is susceptible to the shear stress and yet has to sustain the dynamic load under the spacecraft launch environment. The added features that help the TEC to withstand the dynamic load will inevitably affect the TEC thermal performance. Some experiences and lessons learned are addressed in this paper.

  15. Effects of galvanic skin response feedback on user experience in gaze-controlled gaming: A pilot study.

    PubMed

    Larradet, Fanny; Barresi, Giacinto; Mattos, Leonardo S

    2017-07-01

    Eye-tracking (ET) is one of the most intuitive solutions for enabling people with severe motor impairments to control devices. Nevertheless, even such an effective assistive solution can detrimentally affect user experience during demanding tasks because of, for instance, the user's mental workload - using gaze-based controls for an extensive period of time can generate fatigue and cause frustration. Thus, it is necessary to design novel solutions for ET contexts able to improve the user experience, with particular attention to its aspects related to workload. In this paper, a pilot study evaluates the effects of a relaxation biofeedback system on the user experience in the context of a gaze-controlled task that is mentally and temporally demanding: ET-based gaming. Different aspects of the subjects' experience were investigated under two conditions of a gaze-controlled game. In the Biofeedback group (BF), the user triggered a command by means of voluntary relaxation, monitored through Galvanic Skin Response (GSR) and represented by visual feedback. In the No Biofeedback group (NBF), the same feedback was timed according to the average frequency of commands in BF. After the experiment, each subject filled out a user experience questionnaire. The results showed a general appreciation for BF, with a significant between-group difference in the perceived session time duration, with the latter being shorter for subjects in BF than for the ones in NBF. This result implies a lower mental workload for BF than for NBF subjects. Other results point toward a potential role of user's engagement in the improvement of user experience in BF. Such an effect highlights the value of relaxation biofeedback for improving the user experience in a demanding gaze-controlled task.

  16. Lunar Reconnaissance Orbiter (LRO) Thruster Control Mode Design and Flight Experience

    NASA Technical Reports Server (NTRS)

    Hsu, Oscar C.

    2010-01-01

    National Aeronautics and Space Administration s (NASA) Goddard Space Flight Center (GSFC) in Greenbelt, MD, designed, built, tested, and launched the Lunar Reconnaissance Orbiter (LRO) from Cape Canaveral Air Force Station on June 18, 2009. The LRO spacecraft is the first operational spacecraft designed to support NASA s return to the Moon, as part of the Vision for Space Exploration. LRO was launched aboard an Atlas V 401 launch vehicle into a direct insertion trajectory to the Moon. Twenty-four hours after separation the propulsion system was used to perform a mid-course correction maneuver. Four days after the mid-course correction a series of propulsion maneuvers were executed to insert LRO into its commissioning orbit. The commission period lasted eighty days and this followed by a second set of thruster maneuvers that inserted LRO into its mission orbit. To date, the spacecraft has been gathering invaluable data in support of human s future return to the moon. The LRO Attitude Control Systems (ACS) contains two thruster based control modes: Delta-H and Delta-V. The design of the two controllers are similar in that they are both used for 3-axis control of the spacecraft with the Delta-H controller used for momentum management and the Delta-V controller used for orbit adjust and maintenance maneuvers. In addition to the nominal purpose of the thruster modes, the Delta-H controller also has the added capability of performing a large angle slew maneuver. A suite of ACS components are used by the thruster based control modes, for both initialization and control. For initialization purposes, a star tracker or the Kalman Filter solution is used for providing attitude knowledge and upon entrance into the thruster based control modes attitude knowledge is provided via rate propagation using a inertial reference unit (IRU). Rate information for the controller is also supplied by the IRU. Three-axis control of the spacecraft in the thruster modes is provided by eight 5

  17. Cooperative Adaptive Cruise Control Human Factors Study : Experiment 2 : Merging Behavior

    DOT National Transportation Integrated Search

    2016-12-01

    This study is the second in a series of four experiments exploring human factors issues associated with the introduction of cooperative adaptive cruise control (CACC). Specifically, this study explored drivers abilities to merge into a stream of c...

  18. Controlled ecological life support system higher plant flight experiments

    NASA Technical Reports Server (NTRS)

    Tibbitts, T. W.; Wheeler, R. M.

    1984-01-01

    Requirements for spaceflight experments which involve higher plants were determined. The plants are studied for use in controlled ecological life support systems (CELSS). Two categories of research requirements are discussed: (1) the physical needs which include nutrient, water and gas exchange requirements; (2) the biological and physiological functions which affect plants in zero gravity environments. Physical problems studies are given the priority since they affect all biological experiments.

  19. Adaptive Augmenting Control Flight Characterization Experiment on an F/A-18

    NASA Technical Reports Server (NTRS)

    VanZwieten, Tannen S.; Orr, Jeb S.; Wall, John H.; Gilligan, Eric T.

    2014-01-01

    This paper summarizes the Adaptive Augmenting Control (AAC) flight characterization experiments performed using an F/A-18 (TN 853). AAC was designed and developed specifically for launch vehicles, and is currently part of the baseline autopilot design for NASA's Space Launch System (SLS). The scope covered here includes a brief overview of the algorithm (covered in more detail elsewhere), motivation and benefits of flight testing, top-level SLS flight test objectives, applicability of the F/A-18 as a platform for testing a launch vehicle control design, test cases designed to fully vet the AAC algorithm, flight test results, and conclusions regarding the functionality of AAC. The AAC algorithm developed at Marshall Space Flight Center is a forward loop gain multiplicative adaptive algorithm that modifies the total attitude control system gain in response to sensed model errors or undesirable parasitic mode resonances. The AAC algorithm provides the capability to improve or decrease performance by balancing attitude tracking with the mitigation of parasitic dynamics, such as control-structure interaction or servo-actuator limit cycles. In the case of the latter, if unmodeled or mismodeled parasitic dynamics are present that would otherwise result in a closed-loop instability or near instability, the adaptive controller decreases the total loop gain to reduce the interaction between these dynamics and the controller. This is in contrast to traditional adaptive control logic, which focuses on improving performance by increasing gain. The computationally simple AAC attitude control algorithm has stability properties that are reconcilable in the context of classical frequency-domain criteria (i.e., gain and phase margin). The algorithm assumes that the baseline attitude control design is well-tuned for a nominal trajectory and is designed to adapt only when necessary. Furthermore, the adaptation is attracted to the nominal design and adapts only on an as-needed basis

  20. The laser control of the muon g -2 experiment at Fermilab

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anastasi, A.; Anastasio, A.; Avino, S.

    Here, we present that the Muon g-2 Experiment at Fermilab is expected to start data taking in 2017. It will measure the muon anomalous magnetic moment, a μ = (g μ-2)/2 to an unprecedented precision: the goal is 0.14 parts per million (ppm). The new experiment will require upgrades of detectors, electronics and data acquisition equipment to handle the much higher data volumes and slightly higher instantaneous rates. In particular, it will require a continuous monitoring and state-of-art calibration of the detectors, whose response may vary on both the millisecond and hour long timescale. The calibration system is composed ofmore » six laser sources and a light distribution system will provide short light pulses directly into each crystal (54) of the 24 calorimeters which measure energy and arrival time of the decay positrons. A Laser Control board will manage the interface between the experiment and the laser source, allowing the generation of light pulses according to specific needs including detector calibration, study of detector performance in running conditions, evaluation of DAQ performance. Here we present and discuss the main features of the Laser Control board.« less

  1. The laser control of the muon g -2 experiment at Fermilab

    DOE PAGES

    Anastasi, A.; Anastasio, A.; Avino, S.; ...

    2017-11-09

    Here, we present that the Muon g-2 Experiment at Fermilab is expected to start data taking in 2017. It will measure the muon anomalous magnetic moment, a μ = (g μ-2)/2 to an unprecedented precision: the goal is 0.14 parts per million (ppm). The new experiment will require upgrades of detectors, electronics and data acquisition equipment to handle the much higher data volumes and slightly higher instantaneous rates. In particular, it will require a continuous monitoring and state-of-art calibration of the detectors, whose response may vary on both the millisecond and hour long timescale. The calibration system is composed ofmore » six laser sources and a light distribution system will provide short light pulses directly into each crystal (54) of the 24 calorimeters which measure energy and arrival time of the decay positrons. A Laser Control board will manage the interface between the experiment and the laser source, allowing the generation of light pulses according to specific needs including detector calibration, study of detector performance in running conditions, evaluation of DAQ performance. Here we present and discuss the main features of the Laser Control board.« less

  2. Experiments study on attitude coupling control method for flexible spacecraft

    NASA Astrophysics Data System (ADS)

    Wang, Jie; Li, Dongxu

    2018-06-01

    High pointing accuracy and stabilization are significant for spacecrafts to carry out Earth observing, laser communication and space exploration missions. However, when a spacecraft undergoes large angle maneuver, the excited elastic oscillation of flexible appendages, for instance, solar wing and onboard antenna, would downgrade the performance of the spacecraft platform. This paper proposes a coupling control method, which synthesizes the adaptive sliding mode controller and the positive position feedback (PPF) controller, to control the attitude and suppress the elastic vibration simultaneously. Because of its prominent performance for attitude tracking and stabilization, the proposed method is capable of slewing the flexible spacecraft with a large angle. Also, the method is robust to parametric uncertainties of the spacecraft model. Numerical simulations are carried out with a hub-plate system which undergoes a single-axis attitude maneuver. An attitude control testbed for the flexible spacecraft is established and experiments are conducted to validate the coupling control method. Both numerical and experimental results demonstrate that the method discussed above can effectively decrease the stabilization time and improve the attitude accuracy of the flexible spacecraft.

  3. Seeing conflict and engaging control: Experience with contrastive language benefits executive function in preschoolers

    PubMed Central

    Doebel, Sabine; Zelazo, Philip David

    2016-01-01

    Engaging executive function often requires overriding a prepotent response in favor of a conflicting but adaptive one. Language may play a key role in this ability by supporting integrated representations of conflicting rules. We tested whether experience with contrastive language that could support such representations benefits executive function in 3-year-old children. Children who received brief experience with language highlighting contrast between objects, attributes, and actions showed greater executive function on two of three ‘conflict’ executive function tasks than children who received experience with contrasting stimuli only and children who read storybooks with the experimenter, controlling for baseline executive function. Experience with contrasting stimuli did not benefit executive function relative to reading books with the experimenter, indicating experience with contrastive language, rather than experience with contrast generally, was key. Experience with contrastive language also boosted spontaneous attention to contrast, consistent with improvements in representing contrast. These findings indicate a role for language in executive function that is consistent with the Cognitive Complexity and Control theory's key claim that coordinating conflicting rules is critical to overcoming perseveration, and suggest new ideas for testing theories of executive function. PMID:27658118

  4. Seeing conflict and engaging control: Experience with contrastive language benefits executive function in preschoolers.

    PubMed

    Doebel, Sabine; Zelazo, Philip David

    2016-12-01

    Engaging executive function often requires overriding a prepotent response in favor of a conflicting but adaptive one. Language may play a key role in this ability by supporting integrated representations of conflicting rules. We tested whether experience with contrastive language that could support such representations benefits executive function in 3-year-old children. Children who received brief experience with language highlighting contrast between objects, attributes, and actions showed greater executive function on two of three 'conflict' executive function tasks than children who received experience with contrasting stimuli only and children who read storybooks with the experimenter, controlling for baseline executive function. Experience with contrasting stimuli did not benefit executive function relative to reading books with the experimenter, indicating experience with contrastive language, rather than experience with contrast generally, was key. Experience with contrastive language also boosted spontaneous attention to contrast, consistent with improvements in representing contrast. These findings indicate a role for language in executive function that is consistent with the Cognitive Complexity and Control theory's key claim that coordinating conflicting rules is critical to overcoming perseveration, and suggest new ideas for testing theories of executive function. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Potential for geophysical experiments in large scale tests.

    USGS Publications Warehouse

    Dieterich, J.H.

    1981-01-01

    Potential research applications for large-specimen geophysical experiments include measurements of scale dependence of physical parameters and examination of interactions with heterogeneities, especially flaws such as cracks. In addition, increased specimen size provides opportunities for improved recording resolution and greater control of experimental variables. Large-scale experiments using a special purpose low stress (100MPa).-Author

  6. Conceptual design studies of control and instrumentation systems for ignition experiments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nicholson, P.J.; Dewolf, J.B.; Heinemann, P.C.

    1978-03-01

    Studies at the Charles Stark Draper Laboratory in the past year were a continuation of prior studies of control and instrumentation systems for current and next generation Tokomaks. Specifically, the FY 77 effort has focused on the following two main efforts: (1) control requirements--(a) defining and evolving control requirements/concepts for a prototype experimental power reactor(s), and (b) defining control requirements for diverters and mirror machines, specifically the MX; and (2) defining requirements and scoping design for a functional control simulator. Later in the year, a small additional task was added: (3) providing analysis and design support to INESCO for itsmore » low cost fusion power system, FPC/DMT.« less

  7. Mango and acerola pulps as antioxidant additives in cassava starch bio-based film.

    PubMed

    Souza, Carolina O; Silva, Luciana T; Silva, Jaff R; López, Jorge A; Veiga-Santos, Pricila; Druzian, Janice I

    2011-03-23

    The objective of this study was to investigate the feasibility of incorporating mango and acerola pulps into a biodegradable matrix as a source of polyphenols, carotenoids, and other antioxidant compounds. We also sought to evaluate the efficacy of mango and acerola pulps as antioxidants in film-forming dispersions using a response surface methodology design experiment. The bio-based films were used to pack palm oil (maintained for 45 days of storage) under accelerated oxidation conditions (63% relative humidity and 30 °C) to simulate a storage experiment. The total carotenoid, total polyphenol, and vitamin C contents of films were evaluated, while the total carotenoid, peroxide index, conjugated diene, and hexanal content of the packaged product (palm oil) were also monitored. The same analysis also evaluated palm oil packed in films without antioxidant additives (C1), palm oil packed in low-density polyethylene films (C2), and palm oil with no package (C3) as a control. Although the film-forming procedure affected the antioxidant compounds, the results indicated that antioxidants were effective additives for protecting the packaged product. A lower peroxide index (36.12%), which was significantly different from that of the control (p<0.05), was detected in products packed in film formulations containing high concentration of additives. However, it was found that the high content of vitamin C in acerola pulp acted as a prooxidant agent, which suggests that the use of rich vitamin C pulps should be avoided as additives for films.

  8. ALMA test interferometer control system: past experiences and future developments

    NASA Astrophysics Data System (ADS)

    Marson, Ralph G.; Pokorny, Martin; Kern, Jeff; Stauffer, Fritz; Perrigouard, Alain; Gustafsson, Birger; Ramey, Ken

    2004-09-01

    The Atacama Large Millimeter Array (ALMA) will, when it is completed in 2012, be the world's largest millimeter & sub-millimeter radio telescope. It will consist of 64 antennas, each one 12 meters in diameter, connected as an interferometer. The ALMA Test Interferometer Control System (TICS) was developed as a prototype for the ALMA control system. Its initial task was to provide sufficient functionality for the evaluation of the prototype antennas. The main antenna evaluation tasks include surface measurements via holography and pointing accuracy, measured at both optical and millimeter wavelengths. In this paper we will present the design of TICS, which is a distributed computing environment. In the test facility there are four computers: three real-time computers running VxWorks (one on each antenna and a central one) and a master computer running Linux. These computers communicate via Ethernet, and each of the real-time computers is connected to the hardware devices via an extension of the CAN bus. We will also discuss our experience with this system and outline changes we are making in light of our experiences.

  9. Effect of video-game experience and position of flight stick controller on simulated-flight performance.

    PubMed

    Cho, Bo-Keun; Aghazadeh, Fereydoun; Al-Qaisi, Saif

    2012-01-01

    The purpose of this study was to determine the effects of video-game experience and flight-stick position on flying performance. The study divided participants into 2 groups; center- and side-stick groups, which were further divided into high and low level of video-game experience subgroups. The experiment consisted of 7 sessions of simulated flying, and in the last session, the flight stick controller was switched to the other position. Flight performance was measured in terms of the deviation of heading, altitude, and airspeed from their respective requirements. Participants with high experience in video games performed significantly better (p < .001) than the low-experienced group. Also, participants performed significantly better (p < .001) with the center-stick than the side-stick. When the side-stick controller was switched to the center-stick position, performance scores continued to increase (0.78 %). However, after switching from a center- to a side-stick controller, performance scores decreased (4.8%).

  10. Memory-guided selective attention: Single experiences with conflict have long-lasting effects on cognitive control.

    PubMed

    Brosowsky, Nicholaus P; Crump, Matthew J C

    2018-05-17

    Adjustments in cognitive control, as measured by congruency sequence effects, are thought to be influenced by both external stimuli and internal goals. However, this dichotomy has often overshadowed the potential contribution of past experience stored in memory. Here, we examine the role of long-term episodic memory in guiding selective attention. Our aim was to demonstrate new evidence that selective attention can be modulated by long-term retrieval of stimulus-specific attentional control settings. All the experiments used a modified flanker task involving multiple unique stimuli. Critically, each stimulus was only presented twice during the experiment: first as a prime, and second as a probe. Experiments 1 and 2 varied the number of intervening trials between prime and probe and manipulated the amount of conflict using a secondary task. Experiment 3 ensured that specific colors assigned to prime stimuli were not repeated when presented as probes. Across both Experiments 1 and 2, we consistently found smaller congruency effects on probe trials when its associated prime trial was incongruent compared with congruent, demonstrating long-term congruency sequence effects. However, Experiment 3 showed no evidence for long-term effects. These findings suggest long-term preservation of selective attention processing at the episodic level, and implicate a role for memory in updating cognitive control. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  11. Tobacco control advocates must demand high-quality media campaigns: the California experience.

    PubMed

    Balbach, E D; Glantz, S A

    1998-01-01

    To document efforts on the part of public officials in California to soften the media campaign's attack on the tobacco industry and to analyse strategies to counter those efforts on the part of tobacco control advocates. Data were gathered from interviews with programme participants, direct observation, written materials, and media stories. In addition, internal documents were released by the state's Department of Health Services in response to requests made under the California Public Records Act by Americans for Nonsmokers' Rights. Finally, a draft of the paper was circulated to 11 key players for their comments. In 1988 california voters enacted Proposition 99, an initiative that raised the tobacco tax by $0.25 and allocated 20% of the revenues to anti-tobacco education. A media campaign, which was part of the education programme, directly attacked the tobacco industry, exposing the media campaign to politically based efforts to shut it down or soften it. Through use of outsider strategies such as advertising, press conferences, and public meetings, programme advocates were able to counter the efforts to soften the campaign. Anti-tobacco media campaigns that expose industry manipulation are a key component of an effective tobacco control programme. The effectiveness of these campaigns, however, makes them a target for elimination by the tobacco industry. The experience from California demonstrates the need for continuing, aggressive intervention by nongovernmental organisations in order to maintain the quality of anti-tobacco media campaigns.

  12. Mitigation of Humic Acid Inhibition in Anaerobic Digestion of Cellulose by Addition of Various Salts.

    PubMed

    Azman, Samet; Khadem, Ahmad F; Zeeman, Grietje; van Lier, Jules B; Plugge, Caroline M

    2015-03-25

    Humic compounds are inhibitory to the anaerobic hydrolysis of cellulosic biomass. In this study, the impact of salt addition to mitigate the inhibitory effects of humic compounds was investigated. The experiment was conducted using batch tests to monitor the anaerobic hydrolysis of cellulose in the presence of humic acid. Sodium, potassium, calcium, magnesium and iron salts were tested separately for their efficiency to mitigate humic acid inhibition. All experiments were done under mesophilic conditions (30 °C) and at pH 7. Methane production was monitored online, using the Automatic Methane Potential Test System. Methane production, soluble chemical oxygen demand and volatile fatty acid content of the samples were measured to calculate the hydrolysis efficiencies. Addition of magnesium, calcium and iron salts clearly mitigated the inhibitory effects of humic acid and hydrolysis efficiencies reached up to 75%, 65% and 72%, respectively, which were similar to control experiments. Conversely, potassium and sodium salts addition did not mitigate the inhibition and hydrolysis efficiencies were found to be less than 40%. Mitigation of humic acid inhibition via salt addition was also validated by inductively coupled plasma atomic emission spectroscopy analyses, which showed the binding capacity of different cations to humic acid.

  13. Contamination control program plan for the ultraviolet spectrometer experiment, revision E

    NASA Technical Reports Server (NTRS)

    Gilmore, D. B.

    1972-01-01

    The contamination control program plan delineates the cleanliness requirements to be attained and maintained, and the methods to be utilized, in the fabrication, handling, test, calibration, shipment, pre-installation checkout and installation for the ultraviolet spectrometer experiment prototype, qualification and flight equipment.

  14. Vortex breakdown and control experiments in the Ames-Dryden water tunnel

    NASA Technical Reports Server (NTRS)

    Owen, F. K.; Peake, D. J.

    1986-01-01

    Flow-field measurements have been made to determine the effects of core blowing on vortex breakdown and control. The results of these proof-of-concept experiments clearly demonstrate the usefulness of water tunnels as test platforms for advanced flow-field simulation and measurement.

  15. A computer simulation experiment of supervisory control of remote manipulation. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Mccandlish, S. G.

    1966-01-01

    A computer simulation of a remote manipulation task and a rate-controlled manipulator is described. Some low-level automatic decision making ability which could be used at the operator's discretion to augment his direct continuous control was built into the manipulator. Experiments were made on the effect of transmission delay, dynamic lag, and intermittent vision on human manipulative ability. Delay does not make remote manipulation impossible. Intermittent visual feedback, and the absence of rate information in the display presented to the operator do not seem to impair the operator's performance. A small-capacity visual feedback channel may be sufficient for remote manipulation tasks, or one channel might be time-shared between several operators. In other experiments the operator called in sequence various on-site automatic control programs of the machine, and thereby acted as a supervisor. The supervisory mode of operation has some advantages when the task to be performed is difficult for a human controlling directly.

  16. The spacecraft control laboratory experiment optical attitude measurement system

    NASA Technical Reports Server (NTRS)

    Welch, Sharon S.; Montgomery, Raymond C.; Barsky, Michael F.

    1991-01-01

    A stereo camera tracking system was developed to provide a near real-time measure of the position and attitude of the Spacecraft COntrol Laboratory Experiment (SCOLE). The SCOLE is a mockup of the shuttle-like vehicle with an attached flexible mast and (simulated) antenna, and was designed to provide a laboratory environment for the verification and testing of control laws for large flexible spacecraft. Actuators and sensors located on the shuttle and antenna sense the states of the spacecraft and allow the position and attitude to be controlled. The stereo camera tracking system which was developed consists of two position sensitive detector cameras which sense the locations of small infrared LEDs attached to the surface of the shuttle. Information on shuttle position and attitude is provided in six degrees-of-freedom. The design of this optical system, calibration, and tracking algorithm are described. The performance of the system is evaluated for yaw only.

  17. Possible applications of the LEAP motion controller for more interactive simulated experiments in augmented or virtual reality

    NASA Astrophysics Data System (ADS)

    Wozniak, Peter; Vauderwange, Oliver; Mandal, Avikarsha; Javahiraly, Nicolas; Curticapean, Dan

    2016-09-01

    Practical exercises are a crucial part of many curricula. Even simple exercises can improve the understanding of the underlying subject. Most experimental setups require special hardware. To carry out e. g. a lens experiments the students need access to an optical bench, various lenses, light sources, apertures and a screen. In our previous publication we demonstrated the use of augmented reality visualization techniques in order to let the students prepare with a simulated experimental setup. Within the context of our intended blended learning concept we want to utilize augmented or virtual reality techniques for stationary laboratory exercises. Unlike applications running on mobile devices, stationary setups can be extended more easily with additional interfaces and thus allow for more complex interactions and simulations in virtual reality (VR) and augmented reality (AR). The most significant difference is the possibility to allow interactions beyond touching a screen. The LEAP Motion controller is a small inexpensive device that allows for the tracking of the user's hands and fingers in three dimensions. It is conceivable to allow the user to interact with the simulation's virtual elements by the user's very hand position, movement and gesture. In this paper we evaluate possible applications of the LEAP Motion controller for simulated experiments in augmented and virtual reality. We pay particular attention to the devices strengths and weaknesses and want to point out useful and less useful application scenarios.

  18. Alcohol Use During Pregnancy. [and] Fast Food and the American Diet. [and] Food Additives and Hyperactivity.

    ERIC Educational Resources Information Center

    Smith, Terrence; And Others

    These three separate pamphlets provide background information, brief discussions of research findings, and guidelines and recommendations concerning selected aspects of diet. The first pamphlet discusses food additives and hyperactivity, focusing on both the Feingold theory and controlled experiments which do not support Feingold's clinical…

  19. Preservice Students' Attitudes toward Pupil Control as They Develop throughout the Field Experiences.

    ERIC Educational Resources Information Center

    Killian, Joyce E.; McIntyre, D. John

    This study used repeated measures of the Pupil Control Ideology (PCI) instrument to examine the change in student teacher orientation toward pupil control ideology occurring during a three semester field experience. The instrument was given to elementary and secondary education majors at Southern Illinois University at Carbondale five different…

  20. Direct experience while eating: Laboratory outcomes among individuals with eating disorders versus healthy controls.

    PubMed

    Elices, Matilde; Carmona, Cristina; Narváez, Vanessa; Seto, Victoria; Martin-Blanco, Ana; Pascual, Juan C; Soriano, José; Soler, Joaquim

    2017-12-01

    To compare individuals with eating disorders (EDs) to healthy controls (HCs) to assess for differences in direct engagement in the eating process. Participants (n=58) were asked to eat an orange slice. To assess the degree of direct engagement with the eating process, participants were asked to write down 10 thoughts about the experience of eating the orange slice. Next, the participants were instructed to classify the main focus of each thought as either experiential ("direct experience") or analytical ("thinking about"). A direct experience index (DEI) was computed by dividing the number of times that participants classified an experience as a "direct experience" (the numerator) by the total number of all observations (i.e., direct experience+thinking about). Participants also completed the Five Facet Mindfulness Questionnaire (FFMQ) and the Experiences Questionnaire (EQ) to assess mindfulness facets and decentering, respectively. Compared to controls, participants in the EDs group presented significantly lower levels of direct experience during the eating task (EDs group: mean=43.54, SD=29.64; HCs group: mean=66.17, SD=22.23, p=0.03). Participants in the EDs group also scored significantly lower on other mindfulness-related variables. These findings suggest that engagement with the direct experience of eating is lower in individuals with EDs. Future research should investigate the role of mindfulness-based interventions to address direct experience while eating in individuals with EDs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Experiments on vibration control of a piezoelectric laminated paraboloidal shell

    NASA Astrophysics Data System (ADS)

    Yue, Honghao; Lu, Yifan; Deng, Zongquan; Tzou, Hornsen

    2017-01-01

    A paraboloidal shell plays a key role in aerospace and optical structural systems applied to large optical reflector, communications antenna, rocket fairing, missile radome, etc. Due to the complexity of analytical procedures, an experimental study of active vibration control of a piezoelectric laminated paraboloidal shell by positive position feedback is carried out. Sixteen PVDF patches are laminated inside and outside of the shell, in which eight of them are used as sensors and eight as actuators to control the vibration of the first two natural modes. Lower natural frequencies and vibration modes of the paraboloidal shell are obtained via the frequency response function analysis by Modal VIEW software. A mathematical model of the control system is formulated by means of parameter identification. The first shell mode is controlled as well as coupled the first and second modes based on the positive position feedback (PPF) algorithm. To minimize the control energy consumption in orbit, an adaptive modal control method is developed in this study by using the PPF in laboratory experiments. The control system collects vibration signals from the piezoelectric sensors to identify location(s) of the largest vibration amplitudes and then select the best two from eight PVDF actuators to apply control forces so that the modal vibration suppression could be accomplished adaptively and effectively.

  2. The use of a Nintendo Wii remote control in physics experiments

    NASA Astrophysics Data System (ADS)

    Abellán, F. J.; Arenas, A.; Núñez, M. J.; Victoria, L.

    2013-09-01

    In this paper we describe how a Nintendo Wii remote control (known as the Wiimote) can be used in the design and implementation of several undergraduate-level experiments in a physics laboratory class. An experimental setup composed of a Wiimote and a conveniently located IR LED allows the trajectory of one or several moving objects to be tracked and recorded accurately, in both long and short displacement. The authors have developed a user interface program to configure the operation of the acquisition system of such data. The two experiments included in this work are the free fall of a body with magnetic braking and the simple pendulum, but other physics experiments could have been chosen. The treatment of the data was performed using Bayesian inference.

  3. Evaluation of the Fluids Mixing Enclosure System for Life Science Experiments During a Commercial Caenorhabditis elegans Spaceflight Experiment.

    PubMed

    Warren, Paul; Golden, Andy; Hanover, John; Love, Dona; Shephard, Freya; Szewczyk, Nathaniel J

    2013-06-01

    The Student Spaceflight Experiments Program (SSEP) is a United States national science, technology, engineering, and mathematics initiative that aims to increase student interest in science by offering opportunities to perform spaceflight experiments. The experiment detailed here was selected and flown aboard the third SSEP mission and the first SSEP mission to the International Space Station (ISS). Caenorhabditis elegans is a small, transparent, self-fertilizing hermaphroditic roundworm that is commonly used in biological experiments both on Earth and in Low Earth Orbit. Past experiments have found decreased expression of mRNA for several genes whose expression can be controlled by the FOXO transcription factor DAF-16. We flew a daf-16 mutant and control worms to determine if the effects of spaceflight on C. elegans are mediated by DAF-16. The experiment used a Type Two Fluids Mixing Enclosure (FME), developed by Nanoracks LLC, and was delivered to the ISS aboard the SpaceX Dragon and returned aboard the Russian Soyuz. The short time interval between experiment selection and the flight rendered preflight experiment verification tests impossible. In addition, published research regarding the viability of the FME in life science experiments was not available. The experiment was therefore structured in such a way as to gather the needed data. Here we report that C. elegans can survive relatively short storage and activation in the FME but cannot produce viable populations for post-flight analysis on extended missions. The FME appears to support short-duration life science experiments, potentially on supply or crew exchange missions, but not on longer ISS expeditions. Additionally, the flown FME was not properly activated, reportedly due to a flaw in training procedures. We suggest that a modified transparent FME could prevent similar failures in future flight experiments.

  4. Evaluation of the fluids mixing enclosure system for life science experiments during a commercial Caenorhabditis elegans spaceflight experiment

    NASA Astrophysics Data System (ADS)

    Warren, Paul; Golden, Andy; Hanover, John; Love, Dona; Shephard, Freya; Szewczyk, Nathaniel J.

    2013-06-01

    The Student Spaceflight Experiments Program (SSEP) is a United States national science, technology, engineering, and mathematics initiative that aims to increase student interest in science by offering opportunities to perform spaceflight experiments. The experiment detailed here was selected and flown aboard the third SSEP mission and the first SSEP mission to the International Space Station (ISS). Caenorhabditis elegans is a small, transparent, self-fertilizing hermaphroditic roundworm that is commonly used in biological experiments both on Earth and in Low Earth Orbit. Past experiments have found decreased expression of mRNA for several genes whose expression can be controlled by the FOXO transcription factor DAF-16. We flew a daf-16 mutant and control worms to determine if the effects of spaceflight on C. elegans are mediated by DAF-16. The experiment used a Type Two Fluids Mixing Enclosure (FME), developed by Nanoracks LLC, and was delivered to the ISS aboard the SpaceX Dragon and returned aboard the Russian Soyuz. The short time interval between experiment selection and the flight rendered preflight experiment verification tests impossible. In addition, published research regarding the viability of the FME in life science experiments was not available. The experiment was therefore structured in such a way as to gather the needed data. Here we report that C. elegans can survive relatively short storage and activation in the FME but cannot produce viable populations for post-flight analysis on extended missions. The FME appears to support short-duration life science experiments, potentially on supply or crew exchange missions, but not on longer ISS expeditions. Additionally, the flown FME was not properly activated, reportedly due to a flaw in training procedures. We suggest that a modified transparent FME could prevent similar failures in future flight experiments.

  5. Evaluation of the Fluids Mixing Enclosure System for Life Science Experiments During a Commercial Caenorhabditis elegans Spaceflight Experiment

    PubMed Central

    Warren, Paul; Golden, Andy; Hanover, John; Love, Dona; Shephard, Freya; Szewczyk, Nathaniel J.

    2013-01-01

    The Student Spaceflight Experiments Program (SSEP) is a United States national science, technology, engineering, and mathematics initiative that aims to increase student interest in science by offering opportunities to perform spaceflight experiments. The experiment detailed here was selected and flown aboard the third SSEP mission and the first SSEP mission to the International Space Station (ISS). Caenorhabditis elegans is a small, transparent, self-fertilizing hermaphroditic roundworm that is commonly used in biological experiments both on Earth and in Low Earth Orbit. Past experiments have found decreased expression of mRNA for several genes whose expression can be controlled by the FOXO transcription factor DAF-16. We flew a daf-16 mutant and control worms to determine if the effects of spaceflight on C. elegans are mediated by DAF-16. The experiment used a Type Two Fluids Mixing Enclosure (FME), developed by Nanoracks LLC, and was delivered to the ISS aboard the SpaceX Dragon and returned aboard the Russian Soyuz. The short time interval between experiment selection and the flight rendered preflight experiment verification tests impossible. In addition, published research regarding the viability of the FME in life science experiments was not available. The experiment was therefore structured in such a way as to gather the needed data. Here we report that C. elegans can survive relatively short storage and activation in the FME but cannot produce viable populations for post-flight analysis on extended missions. The FME appears to support short-duration life science experiments, potentially on supply or crew exchange missions, but not on longer ISS expeditions. Additionally, the flown FME was not properly activated, reportedly due to a flaw in training procedures. We suggest that a modified transparent FME could prevent similar failures in future flight experiments. PMID:23794777

  6. Robust Tests for Additive Gene-Environment Interaction in Case-Control Studies Using Gene-Environment Independence.

    PubMed

    Liu, Gang; Mukherjee, Bhramar; Lee, Seunggeun; Lee, Alice W; Wu, Anna H; Bandera, Elisa V; Jensen, Allan; Rossing, Mary Anne; Moysich, Kirsten B; Chang-Claude, Jenny; Doherty, Jennifer A; Gentry-Maharaj, Aleksandra; Kiemeney, Lambertus; Gayther, Simon A; Modugno, Francesmary; Massuger, Leon; Goode, Ellen L; Fridley, Brooke L; Terry, Kathryn L; Cramer, Daniel W; Ramus, Susan J; Anton-Culver, Hoda; Ziogas, Argyrios; Tyrer, Jonathan P; Schildkraut, Joellen M; Kjaer, Susanne K; Webb, Penelope M; Ness, Roberta B; Menon, Usha; Berchuck, Andrew; Pharoah, Paul D; Risch, Harvey; Pearce, Celeste Leigh

    2018-02-01

    There have been recent proposals advocating the use of additive gene-environment interaction instead of the widely used multiplicative scale, as a more relevant public health measure. Using gene-environment independence enhances statistical power for testing multiplicative interaction in case-control studies. However, under departure from this assumption, substantial bias in the estimates and inflated type I error in the corresponding tests can occur. In this paper, we extend the empirical Bayes (EB) approach previously developed for multiplicative interaction, which trades off between bias and efficiency in a data-adaptive way, to the additive scale. An EB estimator of the relative excess risk due to interaction is derived, and the corresponding Wald test is proposed with a general regression setting under a retrospective likelihood framework. We study the impact of gene-environment association on the resultant test with case-control data. Our simulation studies suggest that the EB approach uses the gene-environment independence assumption in a data-adaptive way and provides a gain in power compared with the standard logistic regression analysis and better control of type I error when compared with the analysis assuming gene-environment independence. We illustrate the methods with data from the Ovarian Cancer Association Consortium. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Dieting and the self-control of eating in everyday environments: An experience sampling study

    PubMed Central

    Hofmann, Wilhelm; Adriaanse, Marieke; Vohs, Kathleen D.; Baumeister, Roy F.

    2013-01-01

    Objective The literature on dieting has sparked several debates over how restrained eaters differ from unrestrained eaters in their self-regulation of healthy and unhealthy food desires and what distinguishes successful from unsuccessful dieters. We addressed these debates using a four-component model of self-control that was tested using ecological momentary assessment, long-term weight change, and a laboratory measure of inhibitory control. Design A large sample of adults varying in dietary restraint and inhibitory control (as measured by a Stroop task) were equipped with smartphones for a week. They were beeped on random occasions and provided information on their experience and control of healthy and unhealthy food desires in everyday environments. Main Outcome Measures Desire strength, experienced conflict, resistance, enactment of desire, and weight change after a four-month follow-up. Results and Conclusions Dietary restraint was unrelated to desire frequency and strength, but associated with higher conflict experiences and motivation to use self-control with regard to food desires. Most importantly, relationships between and among dietary restraint and resistance, enactment of desire, and long-term weight change were moderated by inhibitory control: Compared to dieters low in response inhibition, dieters high in response inhibition were more likely to attempt to resist food desires, not consume desired food (especially unhealthy food), and objectively lost more weight over the ensuing four months. These results highlight the combinatory effects of aspects of the self-control process in dieters and highlight the value in linking theoretical process frameworks, experience sampling, and laboratory-based assessment in health science. PMID:23751109

  8. Monolithic millimeter-wave diode array beam controllers: Theory and experiment

    NASA Technical Reports Server (NTRS)

    Sjogren, L. B.; Liu, H.-X. L.; Wang, F.; Liu, T.; Wu, W.; Qin, X.-H.; Chung, E.; Domier, C. W.; Luhmann, N. C., Jr.; Maserjian, J.

    1992-01-01

    In the current work, multi-function beam control arrays have been fabricated and have successfully demonstrated amplitude control of transmitted beams in the W and D bands (75-170 GHz). While these arrays are designed to provide beam control under DC bias operation, new designs for high-speed electronic and optical control are under development. These arrays will fill a need for high-speed watt-level beam switches in pulsed reflectometer systems under development for magnetic fusion plasma diagnostics. A second experimental accomplishment of the current work is the demonstration in the 100-170 GHz (D band) frequency range of a new technique for the measurement of the transmission phase as well as amplitude. Transmission data can serve as a means to extract ('de-embed') the grid parameters; phase information provides more complete data to assist in this process. Additional functions of the array beam controller yet to be tested include electronically controlled steering and focusing of a reflected beam. These have application in the areas of millimeter-wave electronic scanning radar and reflectometry, respectively.

  9. Personal control of privacy and data: Estonian experience.

    PubMed

    Priisalu, Jaan; Ottis, Rain

    2017-01-01

    The Republic of Estonia leads Europe in the provision of public digital services. The national communications and transactions platform allows for twenty-first century governance by allowing for transparency, e-safety (inter alia privacy), e-security, entrepreneurship and, among other things, rising levels of prosperity, and well-being for all its Citizens. However, a series of Information Infrastructure attacks against the Estonian e-society infrastructure in 2007 became one of best known incidents and experiences that fundamentally changed both Estonian and international discussions about Cyber Security and Privacy. Estonian experience shows that an open and transparent attitude provides a good foundation for trust between the Citizen and the State, and gives more control to the real owner of the data - the Citizen. Another important lesson is that the Citizen needs to be confident in the government's ability to keep their data safe -- in terms of confidentiality, integrity and availability - establishing a strong link between privacy and information security. This paper discusses certain critical choices, context, and events connected to the birth and growth of the Estonian e-society in terms of Privacy.

  10. The Space Technology-7 Disturbance Reduction System Precision Control Flight Validation Experiment Control System Design

    NASA Technical Reports Server (NTRS)

    O'Donnell, James R.; Hsu, Oscar C.; Maghami, Peirman G.; Markley, F. Landis

    2006-01-01

    As originally proposed, the Space Technology-7 Disturbance Reduction System (DRS) project, managed out of the Jet Propulsion Laboratory, was designed to validate technologies required for future missions such as the Laser Interferometer Space Antenna (LISA). The two technologies to be demonstrated by DRS were Gravitational Reference Sensors (GRSs) and Colloidal MicroNewton Thrusters (CMNTs). Control algorithms being designed by the Dynamic Control System (DCS) team at the Goddard Space Flight Center would control the spacecraft so that it flew about a freely-floating GRS test mass, keeping it centered within its housing. For programmatic reasons, the GRSs were descoped from DRS. The primary goals of the new mission are to validate the performance of the CMNTs and to demonstrate precise spacecraft position control. DRS will fly as a part of the European Space Agency (ESA) LISA Pathfinder (LPF) spacecraft along with a similar ESA experiment, the LISA Technology Package (LTP). With no GRS, the DCS attitude and drag-free control systems make use of the sensor being developed by ESA as a part of the LTP. The control system is designed to maintain the spacecraft s position with respect to the test mass, to within 10 nm/the square root of Hz over the DRS science frequency band of 1 to 30 mHz.

  11. Using embryology screencasts: a useful addition to the student learning experience?

    PubMed

    Evans, Darrell J R

    2011-01-01

    Although podcasting has been a well used resource format in the last few years as a way of improving the student learning experience, the inclusion of enhanced audiovisual formats such as screencasts has been less used, despite the advantage that they work well for both visual and auditory learners. This study examines the use of and student reaction to a set of screencasts introduced to accompany embryology lectures within a second year module at Brighton and Sussex Medical School. Five mini-lecture screencasts and one review quiz screencast were produced as digital recordings of computer screen output with audio narration and released to students via the managed learning environment (MLE). Analysis of server log information from the MLE showed that the screencasts were accessed by many of the students in the cohort, although the exact numbers were variable depending on the screencast. Students accessed screencasts at different times of the day and over the whole of the access period, although maximum downloads were predictably recorded leading up to the written examination. Quantitative and qualitative feedback demonstrated that most students viewed the screencasts favorably in terms of usefulness to their learning, and end-of-module written examination scores suggest that the screencasts may have had a positive effect on student outcome when compared with previous student attainment. Overall, the development of a series of embryology screencasts to accompany embryology lecture sessions appears to be a useful addition to learning for most students and not simply an innovation that checks the box of "technology engagement." Copyright © 2011 American Association of Anatomists.

  12. Drilling mud additives

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Roemer, P.; Downhour, R. Jr.

    1970-06-30

    A drilling mud additive prepared from farinaceous material contains relatively high gluten and fat contents and has between 30 and 40% water soluble solids on a dry basis. The product is particularly useful in rotary drilling as an additive to the drilling mud to inhibit water loss. The key to achieving the desired product is pretreatment of the raw flour and control of moisture. (2 claims)

  13. Statistical physics of human beings in games: Controlled experiments

    NASA Astrophysics Data System (ADS)

    Liang, Yuan; Huang, Ji-Ping

    2014-07-01

    It is important to know whether the laws or phenomena in statistical physics for natural systems with non-adaptive agents still hold for social human systems with adaptive agents, because this implies whether it is possible to study or understand social human systems by using statistical physics originating from natural systems. For this purpose, we review the role of human adaptability in four kinds of specific human behaviors, namely, normal behavior, herd behavior, contrarian behavior, and hedge behavior. The approach is based on controlled experiments in the framework of market-directed resource-allocation games. The role of the controlled experiments could be at least two-fold: adopting the real human decision-making process so that the system under consideration could reflect the performance of genuine human beings; making it possible to obtain macroscopic physical properties of a human system by tuning a particular factor of the system, thus directly revealing cause and effect. As a result, both computer simulations and theoretical analyses help to show a few counterparts of some laws or phenomena in statistical physics for social human systems: two-phase phenomena or phase transitions, entropy-related phenomena, and a non-equilibrium steady state. This review highlights the role of human adaptability in these counterparts, and makes it possible to study or understand some particular social human systems by means of statistical physics coming from natural systems.

  14. Apollo experience report: Command and service module environmental control system

    NASA Technical Reports Server (NTRS)

    Samonski, F. H., Jr.; Tucker, E. M.

    1972-01-01

    A comprehensive review is presented of the design philosophy of the Apollo environmental control system together with the development history of the total system and of selected components within the system. In particular, discussions are presented relative to the development history and to the problems associated with the equipment cooling coldplates, the evaporator and its electronic control system, and the space radiator system used for rejection of the spacecraft thermal loads. Apollo flight experience and operational difficulties associated with the spacecraft water system and the waste management system are discussed in detail to provide definition of the problem and the corrective action taken when applicable.

  15. Analysis of a boron-carbide-drum-controlled critical reactor experiment

    NASA Technical Reports Server (NTRS)

    Mayo, W. T.

    1972-01-01

    In order to validate methods and cross sections used in the neutronic design of compact fast-spectrum reactors for generating electric power in space, an analysis of a boron-carbide-drum-controlled critical reactor was made. For this reactor the transport analysis gave generally satisfactory results. The calculated multiplication factor for the most detailed calculation was only 0.7-percent Delta k too high. Calculated reactivity worth of the control drums was $11.61 compared to measurements of $11.58 by the inverse kinetics methods and $11.98 by the inverse counting method. Calculated radial and axial power distributions were in good agreement with experiment.

  16. Nitrate removal in stream ecosystems measured by 15N addition experiments: Denitrification

    USGS Publications Warehouse

    Mulholland, P.J.; Hall, R.O.; Sobota, D.J.; Dodds, W.K.; Findlay, S.E.G.; Grimm, N. B.; Hamilton, S.K.; McDowell, W.H.; O'Brien, J. M.; Tank, J.L.; Ashkenas, L.R.; Cooper, L.W.; Dahm, Clifford N.; Gregory, S.V.; Johnson, S.L.; Meyer, J.L.; Peterson, B.J.; Poole, G.C.; Valett, H.M.; Webster, J.R.; Arango, C.P.; Beaulieu, J.J.; Bernot, M.J.; Burgin, A.J.; Crenshaw, C.L.; Helton, A.M.; Johnson, L.T.; Niederlehner, B.R.; Potter, J.D.; Sheibley, R.W.; Thomasn, S.M.

    2009-01-01

    We measured denitrification rates using a field 15N-NO- 3 tracer-addition approach in a large, cross-site study of nitrate uptake in reference, agricultural, and suburban-urban streams. We measured denitrification rates in 49 of 72 streams studied. Uptake length due to denitrification (SWden) ranged from 89 m to 184 km (median of 9050 m) and there were no significant differences among regions or land-use categories, likely because of the wide range of conditions within each region and land use. N2 production rates far exceeded N2O production rates in all streams. The fraction of total NO-3 removal from water due to denitrification ranged from 0.5% to 100% among streams (median of 16%), and was related to NHz 4 concentration and ecosystem respiration rate (ER). Multivariate approaches showed that the most important factors controlling SWden were specific discharge (discharge / width) and NO-3 concentration (positive effects), and ER and transient storage zones (negative effects). The relationship between areal denitrification rate (Uden) and NO- 3 concentration indicated a partial saturation effect. A power function with an exponent of 0.5 described this relationship better than a Michaelis-Menten equation. Although Uden increased with increasing NO- 3 concentration, the efficiency of NO-3 removal from water via denitrification declined, resulting in a smaller proportion of streamwater NO-3 load removed over a given length of stream. Regional differences in stream denitrification rates were small relative to the proximate factors of NO-3 concentration and ecosystem respiration rate, and land use was an important but indirect control on denitrification in streams, primarily via its effect on NO-3 concentration. ?? 2009.

  17. Echoes on the motor network: how internal motor control structures afford sensory experience.

    PubMed

    Burgess, Jed D; Lum, Jarrad A G; Hohwy, Jakob; Enticott, Peter G

    2017-12-01

    Often, during daily experiences, hearing peers' actions can activate motor regions of the CNS. This activation is termed auditory-motor resonance (AMR) and is thought to represent an internal simulation of one's motor memories. Currently, AMR is demonstrated at the neuronal level in the Macaque and songbird, in conjunction with evidence on a systems level in humans. Here, we review evidence of AMR development from a motor control perspective. In the context of internal modelling, we consider data that demonstrates sensory-guided motor learning and action maintenance, particularly the notion of sensory comparison seen during songbird vocalisation. We suggest that these comparisons generate accurate sensory-to-motor inverse mappings. Furthermore, given reports of mapping decay after songbird learning, we highlight the proposal that the maintenance of these sensorimotor maps potentially explains why frontoparietal regions are activated upon hearing known sounds (i.e., AMR). In addition, we also recommend that activation of these types of internal models outside of action execution may provide an ecological advantage when encountering known stimuli in ambiguous conditions.

  18. Parental autonomy granting and child perceived control: effects on the everyday emotional experience of anxious youth.

    PubMed

    Benoit Allen, Kristy; Silk, Jennifer S; Meller, Suzanne; Tan, Patricia Z; Ladouceur, Cecile D; Sheeber, Lisa B; Forbes, Erika E; Dahl, Ronald E; Siegle, Greg J; McMakin, Dana L; Ryan, Neal D

    2016-07-01

    Childhood anxiety is associated with low levels of parental autonomy granting and child perceived control, elevated child emotional reactivity and deficits in child emotion regulation. In early childhood, low levels of parental autonomy granting are thought to decrease child perceived control, which in turn leads to increases in child negative emotion. Later in development, perceived control may become a more stable, trait-like characteristic that amplifies the relationship between parental autonomy granting and child negative emotion. The purpose of this study was to test mediation and moderation models linking parental autonomy granting and child perceived control with child emotional reactivity and emotion regulation in anxious youth. Clinically anxious youth (N = 106) and their primary caregivers were assessed prior to beginning treatment. Children were administered a structured diagnostic interview and participated in a parent-child interaction task that was behaviorally coded for parental autonomy granting. Children completed an ecological momentary assessment protocol during which they reported on perceived control, emotional reactivity (anxiety and physiological arousal) and emotion regulation strategy use in response to daily negative life events. The relationship between parental autonomy granting and both child emotional reactivity and emotion regulation strategy use was moderated by child perceived control: the highest levels of self-reported physiological responding and the lowest levels of acceptance in response to negative events occurred in children low in perceived control with parents high in autonomy granting. Evidence for a mediational model was not found. In addition, child perceived control over negative life events was related to less anxious reactivity and greater use of both problem solving and cognitive restructuring as emotion regulation strategies. Both parental autonomy granting and child perceived control play important roles in the

  19. Parental autonomy granting and child perceived control: Effects on the everyday emotional experience of anxious youth

    PubMed Central

    Allen, Kristy Benoit; Silk, Jennifer S.; Meller, Suzanne; Tan, Patricia Z.; Ladouceur, Cecile D.; Sheeber, Lisa B.; Forbes, Erika E.; Dahl, Ronald E.; Siegle, Greg J.; McMakin, Dana L.; Ryan, Neal D.

    2015-01-01

    Background Childhood anxiety is associated with low levels of parental autonomy granting and child perceived control, elevated child emotional reactivity, and deficits in child emotion regulation. In early childhood, low levels of parental autonomy granting are thought to decrease child perceived control, which in turn leads to increases in child negative emotion. Later in development, perceived control may become a more stable, trait-like characteristic that amplifies the relationship between parental autonomy granting and child negative emotion. The purpose of the current study was to test mediation and moderation models linking parental autonomy granting and child perceived control with child emotional reactivity and emotion regulation in anxious youth. Methods Clinically anxious youth (N = 106) and their primary caregivers were assessed prior to beginning treatment. Children were administered a structured diagnostic interview and participated in a parent-child interaction task that was behaviorally coded for parental autonomy granting. Children completed an ecological momentary assessment protocol during which they reported on perceived control, emotional reactivity (anxiety and physiological arousal), and emotion regulation strategy use in response to daily negative life events. Results The relationship between parental autonomy granting and both child emotional reactivity and emotion regulation strategy use was moderated by child perceived control: the highest levels of self-reported physiological responding and the lowest levels of acceptance in response to negative events occurred in children low in perceived control with parents high in autonomy granting. Evidence for a mediational model was not found. In addition, child perceived control over negative life events was related to less anxious reactivity and greater use of both problem solving and cognitive restructuring as emotion regulation strategies. Conclusion Both parental autonomy granting and child

  20. Additional standing balance circuit classes during inpatient rehabilitation improved balance outcomes: an assessor-blinded randomised controlled trial.

    PubMed

    Treacy, Daniel; Schurr, Karl; Lloyd, Bradley; Sherrington, Catherine

    2015-07-01

    to evaluate the impact on balance (postural control) of six 1-h circuit classes that targeted balance in addition to usual therapy for rehabilitation inpatients. a randomised controlled trial with 2-week and 3-month follow-up. one hundred and sixty-two general rehabilitation inpatients, Bankstown-Lidcombe Hospital, Australia. intervention group participants received six 1-h circuit classes over a 2-week period in addition to usual therapy. Control group participants received usual therapy. standing balance performance (primary outcome) was better in the intervention group than in the control group at 2 weeks (between-group difference after adjusting for baseline values 3.3 s; 95% confidence interval (CI) 0.84 to 5.7, P = 0.009), but the between-group difference was not statistically significant at 3 months (3.4 s; 95% CI -0.56 to 7.38, P = 0.092). Intervention group outcomes were significantly better than the control groups for mobility performance (Short Physical Performance Battery) at 2 weeks (1.19, 95% CI 0.52 to 1.87, P <0.01) and 3 months (1.00, 95% CI 0.00 to 2.00, P < 0.049) and self-reported functioning (AM-PAC) at 2 weeks (5.39, 95% CI 1.20 to 9.57, P = 0.012). The intervention group had a 4.1-day shorter rehabilitation unit stay (95% CI -8.3 to 0.16, P = 0.059) and a lower risk of readmission in the 3 months after randomisation (incidence rate ratio 0.70, 95% CI 0.42 to 1.18, P = 0.184), but these differences were not statistically significant. two weeks of standing balance circuit classes in addition to usual therapy improved balance in general rehabilitation inpatients at 2 weeks. © The Author 2015. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Preliminary experiments on active control of fan noise from a turbofan engine

    NASA Technical Reports Server (NTRS)

    Thomas, R. H.; Burdisso, R. A.; Fuller, C. R.; O'Brien, W. F.

    1993-01-01

    In the preliminary experiments reported here, active acoustic sources positioned around the circumference of a turbofan engine were used to control the fan noise radiated forward through the inlet. The main objective was to demonstrate the potential of active techniques to alleviate the noise pollution that will be produced by the next generation of larger engines. A reduction of up to 19 dB in the radiation directivity was demonstrated in a zone that encompasses a 30-deg angle, near the error sensor, while spillover effects were observed toward the lateral direction. The simultaneous control of two tones was also demonstrated using two identical controllers in a parallel control configuration.

  2. Displaying Special Characters and Symbols in Computer-Controlled Reaction Time Experiments.

    ERIC Educational Resources Information Center

    Friel, Brian M.; Kennison, Shelia M.

    A procedure for using MEL2 (Version 2.0 of Microcomputer Experimental Laboratory) and FontWINDOW to present special characters and symbols in computer-controlled reaction time experiments is described. The procedure permits more convenience and flexibility than in tachistocopic and projection techniques. FontWINDOW allows researchers to design…

  3. The significance of clinical experience on learning outcome from resuscitation training-a randomised controlled study.

    PubMed

    Jensen, Morten Lind; Lippert, Freddy; Hesselfeldt, Rasmus; Rasmussen, Maria Birkvad; Mogensen, Simon Skibsted; Jensen, Michael Kammer; Frost, Torben; Ringsted, Charlotte

    2009-02-01

    The impact of clinical experience on learning outcome from a resuscitation course has not been systematically investigated. To determine whether half a year of clinical experience before participation in an Advanced Life Support (ALS) course increases the immediate learning outcome and retention of learning. This was a prospective single blinded randomised controlled study of the learning outcome from a standard ALS course on a volunteer sample of the entire cohort of newly graduated doctors from Copenhagen University. The outcome measurement was ALS-competence assessed using a validated composite test including assessment of skills and knowledge. The intervention was half a year of clinical work before an ALS course. The intervention group received the course after a half-year of clinical experience. The control group participated in an ALS course immediately following graduation. Invitation to participate was accepted by 154/240 (64%) graduates and 117/154 (76%) completed the study. There was no difference between the intervention and control groups with regard to the immediate learning outcome. The intervention group had significantly higher retention of learning compared to the control group, intervention group mean 82% (CI 80-83), control group mean 78% (CI 76-80), P=0.002. The magnitude of this difference was medium (effect size=0.57). Half a year of clinical experience, before participation in an ALS course had a small but statistically significant impact on the retention of learning, but not on the immediate learning outcome.

  4. Color Addition and Subtraction Apps

    ERIC Educational Resources Information Center

    Ruiz, Frances; Ruiz, Michael J.

    2015-01-01

    Color addition and subtraction apps in HTML5 have been developed for students as an online hands-on experience so that they can more easily master principles introduced through traditional classroom demonstrations. The evolution of the additive RGB color model is traced through the early IBM color adapters so that students can proceed step by step…

  5. The effects of autonomy-supportive and controlling teaching behaviour in biology lessons with primary and secondary experiences on students' intrinsic motivation and flow-experience

    NASA Astrophysics Data System (ADS)

    Hofferber, Natalia; Basten, Melanie; Großmann, Nadine; Wilde, Matthias

    2016-09-01

    Self-Determination Theory and Flow Theory propose that perceived autonomy fosters the positive qualities of motivation and flow-experience. Autonomy-support can help to maintain students' motivation in very interesting learning activities and may lead to an increase in the positive qualities of motivation in less interesting learning activities. This paper investigates whether autonomy-supportive or controlling teaching behaviour influence students' motivation and flow-experience in biology class. In study 1, 158 students of grade six worked on the adaptations of Harvest Mice (Micromys minutus) with living animals. The 153 sixth graders of study 2 dealt with the same content but instead worked with short films on laptops. Previous studies have shown that students perceive film sequences as less interesting than working with living animals. Students' intrinsic motivation and flow-experience were measured at the end of the first and the third lesson. In study 1, autonomy-supportive teaching behaviour led to significant differences in students' intrinsic motivation and flow-experience when compared to controlling teaching behaviour. In study 2, motivation and flow-experience were not always in line with theory. The positive effects of autonomy-supportive and the non-beneficial effects of the controlling teaching behaviour seem to be dependent on the interestingness of the teaching material.

  6. A system for conducting igneous petrology experiments under controlled redox conditions in reduced gravity

    NASA Technical Reports Server (NTRS)

    Williams, R. J.

    1986-01-01

    The Space Shuttle and the planned Space Station will permit experimentation under conditions of reduced gravitational acceleration offering experimental petrologists the opportunity to study crystal growth, element distribution, and phase chemistry. In particular the confounding effects of macro and micro scale buoyancy-induced convection and crystal settling or floatation can be greatly reduced over those observed in experiments in the terrestrial laboratory. Also, for experiments in which detailed replication of the environment is important, the access to reduced gravity will permit a more complete simulation of processes that may have occurred on asteroids or in free space. A technique that was developed to control, measure, and manipulate oxygen fugacites with small quantities of gas which are recirculated over the sample is described. This system should be adaptable to reduced gravity space experiments requiring redox control. Experiments done conventionally and those done using this technique yield identical results done in a 1-g field.

  7. Septic tank additive impacts on microbial populations.

    PubMed

    Pradhan, S; Hoover, M T; Clark, G H; Gumpertz, M; Wollum, A G; Cobb, C; Strock, J

    2008-01-01

    Environmental health specialists, other onsite wastewater professionals, scientists, and homeowners have questioned the effectiveness of septic tank additives. This paper describes an independent, third-party, field scale, research study of the effects of three liquid bacterial septic tank additives and a control (no additive) on septic tank microbial populations. Microbial populations were measured quarterly in a field study for 12 months in 48 full-size, functioning septic tanks. Bacterial populations in the 48 septic tanks were statistically analyzed with a mixed linear model. Additive effects were assessed for three septic tank maintenance levels (low, intermediate, and high). Dunnett's t-test for tank bacteria (alpha = .05) indicated that none of the treatments were significantly different, overall, from the control at the statistical level tested. In addition, the additives had no significant effects on septic tank bacterial populations at any of the septic tank maintenance levels. Additional controlled, field-based research iswarranted, however, to address additional additives and experimental conditions.

  8. Spacecraft Hybrid (Mixed-Actuator) Attitude Control Experiences on NASA Science Missions

    NASA Technical Reports Server (NTRS)

    Dennehy, Cornelius J.

    2014-01-01

    There is a heightened interest within NASA for the design, development, and flight implementation of mixed-actuator hybrid attitude control systems for science spacecraft that have less than three functional reaction wheel actuators. This interest is driven by a number of recent reaction wheel failures on aging, but what could be still scientifically productive, NASA spacecraft if a successful hybrid attitude control mode can be implemented. Over the years, hybrid (mixed-actuator) control has been employed for contingency attitude control purposes on several NASA science mission spacecraft. This paper provides a historical perspective of NASA's previous engineering work on spacecraft mixed-actuator hybrid control approaches. An update of the current situation will also be provided emphasizing why NASA is now so interested in hybrid control. The results of the NASA Spacecraft Hybrid Attitude Control Workshop, held in April of 2013, will be highlighted. In particular, the lessons learned captured from that workshop will be shared in this paper. An update on the most recent experiences with hybrid control on the Kepler spacecraft will also be provided. This paper will close with some future considerations for hybrid spacecraft control.

  9. Effect of Periodic Water Addition on Citric Acid Production in Solid State Fermentation

    NASA Astrophysics Data System (ADS)

    Utpat, Shraddha S.; Kinnige, Pallavi T.; Dhamole, Pradip B.

    2013-09-01

    Water addition is one of the methods used to control the moisture loss in solid state fermentation (SSF). However, none of the studies report the timing of water addition and amount of water to be added in SSF. Therefore, this work was undertaken with an objective to evaluate the performance of periodic water addition on citric acid production in SSF. Experiments were conducted at different moistures (50-80 %) and temperatures (30-40 °C) to simulate the conditions in a fermenter. Citric acid production by Aspergillus niger (ATCC 9029) using sugarcane baggase was chosen as a model system. Based on the moisture profile, citric acid and sugar data, a strategy was designed for periodic addition of water. Water addition at 48, 96, 144 and 192 h enhanced the citric acid production by 62 % whereas water addition at 72, 120, and 168 h increased the citric acid production by just 17 %.

  10. International Space Station Attitude Control and Energy Storage Experiment: Effects of Flywheel Torque

    NASA Technical Reports Server (NTRS)

    Roithmayr, Carlos M.

    1999-01-01

    The Attitude Control and Energy Storage Experiment is currently under development for the International Space Station; two counter-rotating flywheels will be levitated with magnetic bearings and placed in vacuum housings. The primary objective of the experiment is to store and discharge energy, in combination with existing batteries, into the electrical power system. The secondary objective is to use the flywheels to exert torque on the Station; a simple torque profile has been designed so that the Station's Control Moment Gyroscopes will be assisted in maintaining torque equilibrium attitude. Two energy storage contingencies could result in the inadvertent application of torque by the flywheels to the Station: an emergency shutdown of one flywheel rotor while the other remains spinning, and energy storage with only one rotor instead of the counterrotating pair. Analysis of these two contingencies shows that attitude control and the microgravity environment will not be adversely affected.

  11. Near-death experiences and the temporal lobe.

    PubMed

    Britton, Willoughby B; Bootzin, Richard R

    2004-04-01

    Many studies in humans suggest that altered temporal lobe functioning, especially functioning in the right temporal lobe, is involved in mystical and religious experiences. We investigated temporal lobe functioning in individuals who reported having transcendental "near-death experiences" during life-threatening events. These individuals were found to have more temporal lobe epileptiform electroencephalographic activity than control subjects and also reported significantly more temporal lobe epileptic symptoms. Contrary to predictions, epileptiform activity was nearly completely lateralized to the left hemisphere. The near-death experience was not associated with dysfunctional stress reactions such as dissociation, posttraumatic stress disorder, and substance abuse, but rather was associated with positive coping styles. Additional analyses revealed that near-death experiencers had altered sleep patterns, specifically, a shorter duration of sleep and delayed REM sleep relative to the control group. These results suggest that altered temporal lobe functioning may be involved in the near-death experience and that individuals who have had such experiences are physiologically distinct from the general population.

  12. A system for conducting igneous petrology experiments under controlled redox conditions in reduced gravity

    NASA Technical Reports Server (NTRS)

    Williams, Richard J.

    1987-01-01

    The Space Shuttle and the planned Space Station will permit experimentation under conditions of reduced gravitational acceleration offering experimental petrologists the opportunity to study crystal growth, element distribution, and phase chemistry. In particular the confounding effects of macro and micro scale buoyancy-induced convection and crystal settling or flotation can be greatly reduced over those observed in experiments in the terrestrial laboratory. Also, for experiments in which detailed replication of the environment is important, the access to reduced gravity will permit a more complete simulation of processes that may have occurred on asteroids or in free space. A technique that was developed to control, measure, and manipulate oxygen fugacities with small quantities of gas which are recirculated over the sample. This system could be adaptable to reduced gravity space experiments requiring redox control.

  13. Tobacco control advocates must demand high-quality media campaigns: the California experience

    PubMed Central

    Balbach, E.; Glantz, S.

    1998-01-01

    OBJECTIVE—To document efforts on the part of public officials in California to soften the media campaign's attack on the tobacco industry and to analyse strategies to counter those efforts on the part of tobacco control advocates.
METHODS—Data were gathered from interviews with programme participants, direct observation, written materials, and media stories. In addition, internal documents were released by the state's Department of Health Services in response to requests made under the California Public Records Act by Americans for Nonsmokers' Rights. Finally, a draft of the paper was circulated to 11 key players for their comments.
RESULTS—In 1988 California voters enacted Proposition 99, an initiative that raised the tobacco tax by $0.25 and allocated 20% of the revenues to anti-tobacco education. A media campaign, which was part of the education programme, directly attacked the tobacco industry, exposing the media campaign to politically based efforts to shut it down or soften it. Through use of outsider strategies such as advertising, press conferences, and public meetings, programme advocates were able to counter the efforts to soften the campaign.
CONCLUSION—Anti-tobacco media campaigns that expose industry manipulation are a key component of an effective tobacco control programme. The effectiveness of these campaigns, however, makes them a target for elimination by the tobacco industry. The experience from California demonstrates the need for continuing, aggressive intervention by non-governmental organisations in order to maintain the quality of anti-tobacco media campaigns.


Keywords: media campaigns; anti-tobacco advocacy; California PMID:10093175

  14. Mitigation of Humic Acid Inhibition in Anaerobic Digestion of Cellulose by Addition of Various Salts

    PubMed Central

    Azman, Samet; Khadem, Ahmad F.; Zeeman, Grietje; van Lier, Jules B.; Plugge, Caroline M.

    2015-01-01

    Humic compounds are inhibitory to the anaerobic hydrolysis of cellulosic biomass. In this study, the impact of salt addition to mitigate the inhibitory effects of humic compounds was investigated. The experiment was conducted using batch tests to monitor the anaerobic hydrolysis of cellulose in the presence of humic acid. Sodium, potassium, calcium, magnesium and iron salts were tested separately for their efficiency to mitigate humic acid inhibition. All experiments were done under mesophilic conditions (30 °C) and at pH 7. Methane production was monitored online, using the Automatic Methane Potential Test System. Methane production, soluble chemical oxygen demand and volatile fatty acid content of the samples were measured to calculate the hydrolysis efficiencies. Addition of magnesium, calcium and iron salts clearly mitigated the inhibitory effects of humic acid and hydrolysis efficiencies reached up to 75%, 65% and 72%, respectively, which were similar to control experiments. Conversely, potassium and sodium salts addition did not mitigate the inhibition and hydrolysis efficiencies were found to be less than 40%. Mitigation of humic acid inhibition via salt addition was also validated by inductively coupled plasma atomic emission spectroscopy analyses, which showed the binding capacity of different cations to humic acid. PMID:28955013

  15. Personal experiences and emotionality in health-related knowledge exchange in Internet forums: a randomized controlled field experiment comparing responses to facts vs personal experiences.

    PubMed

    Kimmerle, Joachim; Bientzle, Martina; Cress, Ulrike

    2014-12-04

    On the Internet, people share personal experiences as well as facts and objective information. This also holds true for the exchange of health-related information in a variety of Internet forums. In online discussions about health topics, both fact-oriented and strongly personal contributions occur on a regular basis. In this field experiment, we examined in what way the particular type of contribution (ie, factual information vs personal experiences) has an impact on the subsequent communication in health-related Internet forums. For this purpose, we posted parallelized queries to 28 comparable Internet forums; queries were identical with regard to the information contained but included either fact-oriented descriptions or personal experiences related to measles vaccination. In the factual information condition, we posted queries to the forums that contained the neutral summary of a scientific article. In the personal experiences condition, we posted queries to the forums that contained the same information as in the first condition, but were framed as personal experiences We found no evidence that personal experiences evoked more responses (mean 3.79, SD 3.91) from other members of the Internet forums than fact-oriented contributions (mean 2.14, SD 2.93, t26=0.126, P=.219). But personal experiences elicited emotional replies (mean 3.17, SD 1.29) from other users to a greater extent than fact-oriented contributions (mean 2.13, SD 1.29, t81=3.659, P<.001). We suggest that personal experiences elicited more emotional replies due to the process of emotional anchoring of people's own style of communication. We recommend future studies should aim at testing the hypotheses with more general and with less emotionally charged topics, constructing different fact-oriented posts, and examining additional potential factors of influence such as personality factors or particular communication situations.

  16. Diesel engine experiments with oxygen enrichment, water addition and lower-grade fuel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sekar, R.R.; Marr, W.W.; Cole, R.L.

    1990-01-01

    The concept of oxygen enriched air applied to reciprocating engines is getting renewed attention in the context of the progress made in the enrichment methods and the tougher emissions regulations imposed on diesel and gasoline engines. An experimental project was completed in which a direct injection diesel engine was tested with intake oxygen levels of 21% -- 35%. Since an earlier study indicated that it is necessary to use a cheaper fuel to make the concept economically attractive, a less refined fuel was included in the test series. Since a major objection to the use of oxygen enriched combustion airmore » had been the increase in NO{sub x} emissions, a method must be found to reduce NO{sub x}. Introduction of water into the engine combustion process was included in the tests for this purpose. Fuel emulsification with water was the means used here even though other methods could also be used. The teat data indicated a large increase in engine power density, slight improvement in thermal efficiency, significant reductions in smoke and particulate emissions and NO{sub x} emissions controllable with the addition of water. 15 refs., 10 figs., 2 tabs.« less

  17. High-velocity frictional experiments on dolerite and quartzite under controlled pore pressure

    NASA Astrophysics Data System (ADS)

    Togo, T.; Shimamoto, T.; Ma, S.

    2013-12-01

    High-velocity friction experiments on rocks with or without gouge have been conducted mostly under dry conditions and demonstrated dramatic weakening of faults at high velocities (e.g., Di Toro et al., 2011, Nature). Recent experiments under wet conditions (e.g., Ujiie and Tsutsumi, 2010, GRL; Faulkner et al., 2011, GRL) revealed very different behaviors from those of dry faults, but those experiments were done under drained conditions. Experiments with controlled pore pressure Pp are definitely needed to determine mechanical properties of faults under fluid-rich environments such as those in subduction zones. Thus we have developed a pressure vessel that can be attached to our rotary-shear low to high-velocity friction apparatus (Marui Co Ltd., MIS-233-1-76). With a current specimen holder, friction experiments can be done on hollow-cylindrical specimens of 15 and 40 mm in inner and outer diameters, respectively, at controlled Pp to 35 MPa, at effective normal stresses of 3~9 MPa, and at slip rates of 60 mm/year to 2 m/s. An effective normal stress can be applied with a 100 kN hydraulic actuator. We report an outline of the experimental system and preliminary high-velocity experiments on Shanxi dolerite and a quartzite from China that are composed of pyroxene and plagioclase and of almost pure quartz, respectively. High-velocity friction experiments were performed on hollow-cylindrical specimens of Shanxi dolerite at effective normal stresses of 0.13~1.07 MPa and at slip rates of 1, 10, 100 and 1000 mm/sec. All experiments were conducted first with the nitrogen gas filling the pressure vessel (dry tests) and then with a controlled pore-water pressure (wet tests). In the dry tests an axial force was kept at 1 kN and the nitrogen gas pressure was increased in steps to 5 MPa to change an effective normal stress. In the wet tests the specimens were soaked in distilled water in the vessel and Pp was applied by nitrogen gas in a similar manner as in the dry tests

  18. Further Characterization of 394-GHz Gyrotron FU CW GII with Additional PID Control System for 600-MHz DNP-SSNMR Spectroscopy

    NASA Astrophysics Data System (ADS)

    Ueda, Keisuke; Matsuki, Yoh; Fujiwara, Toshimichi; Tatematsu, Yoshinori; Ogawa, Isamu; Idehara, Toshitaka

    2016-09-01

    A 394-GHz gyrotron, FU CW GII, has been designed at the University of Fukui, Japan, for dynamic nuclear polarization (DNP)-enhanced solid-state nuclear magnetic resonance (SSNMR) experiments at 600-MHz 1H resonant frequency. After installation at the Institute for Protein Research (IPR), Osaka University, Japan, a PID feedback control system was equipped to regulate the electron gun heater current for stabilization of the electron beam current, which ultimately achieved stabilization of output power when operating in continuous wave (CW) mode. During exploration to further optimize operating conditions, a continuous tuning bandwidth of approximately 1 GHz was observed by varying the operating voltage at a fixed magnetic field. In the frequency range required for positive DNP enhancement, the output power was improved by increasing the magnetic field and the operating voltage from their initial operational settings. In addition, fine tuning of output frequency by varying the cavity cooling water temperature was demonstrated. These operating conditions and ancillary enhancements are expected to contribute to further enhancement of SSNMR signal.

  19. Precision Pointing Control System (PPCS) system design and analysis. [for gimbaled experiment platforms

    NASA Technical Reports Server (NTRS)

    Frew, A. M.; Eisenhut, D. F.; Farrenkopf, R. L.; Gates, R. F.; Iwens, R. P.; Kirby, D. K.; Mann, R. J.; Spencer, D. J.; Tsou, H. S.; Zaremba, J. G.

    1972-01-01

    The precision pointing control system (PPCS) is an integrated system for precision attitude determination and orientation of gimbaled experiment platforms. The PPCS concept configures the system to perform orientation of up to six independent gimbaled experiment platforms to design goal accuracy of 0.001 degrees, and to operate in conjunction with a three-axis stabilized earth-oriented spacecraft in orbits ranging from low altitude (200-2500 n.m., sun synchronous) to 24 hour geosynchronous, with a design goal life of 3 to 5 years. The system comprises two complementary functions: (1) attitude determination where the attitude of a defined set of body-fixed reference axes is determined relative to a known set of reference axes fixed in inertial space; and (2) pointing control where gimbal orientation is controlled, open-loop (without use of payload error/feedback) with respect to a defined set of body-fixed reference axes to produce pointing to a desired target.

  20. LDR structural experiment definition

    NASA Technical Reports Server (NTRS)

    Russell, Richard A.; Gates, Richard M.

    1988-01-01

    A study was performed to develop the definition of a structural flight experiment for a large precision segmented reflector that would utilize the Space Station. The objective of the study was to use the Large Deployable Reflector (LDR) baseline configuration for focusing on experiment definition activity which would identify the Space Station accommodation requirements and interface constraints. Results of the study defined three Space Station based experiments to demonstrate the technologies needed for an LDR type structure. The basic experiment configurations are the same as the JPL baseline except that the primary mirror truss is 10 meters in diameter instead of 20. The primary objectives of the first experiment are to construct the primary mirror support truss and to determine its structural and thermal characteristics. Addition of the optical bench, thermal shield and primary mirror segments and alignment of the optical components occur on the second experiment. The structure will then be moved to the payload pointing system for pointing, optical control and scientific optical measurement for the third experiment.

  1. Torque controlled rotary-shear experiments reveal pseudotachilites formation-dynamics and precursor events

    NASA Astrophysics Data System (ADS)

    Tisato, Nicola; Cordonnier, Benoit; De Siena, Luca; Lavier, Luc; Di Toro, Giulio

    2017-04-01

    Except few cases, rotary shear tests, which are designed to study dynamic friction and strengthening/weakening mechanisms in seismogenic faults, are performed by imposing, to the specimens, a slipping velocity that is pre-defined. This approach has been adopted from engineering that typically, tests man-made objects that, when functioning, spin or slide at a pre-defined velocity under a pre-defined load. On the other hand, natural earthquakes are the effect of a rupture that nucleates, propagates and arrests in the subsurface. These three phases, and the consequent emerging fault slipping velocity, are controlled by the accumulated and released energy around the seismogenic fault before, during and after the earthquake. Thus, imposing the slipping velocity in laboratory experiments might not represent the best option to uncover many aspects of earthquake nucleation and fault slipping dynamics. Here we present some experiments performed with an innovative rotary shear apparatus that uses a clock-spring that when winded provides to the rotating sample a linearly increasing torque. Thus, the nucleation of simulated events occur spontaneously when the shear stress on the slipping surface overcomes the static friction times the normal load that is controlled by a deadweight. In addition, this method allows studying precursory seismic events resembling natural slow-slip earthquakes. We report some preliminary results for a transparent polymer that has melting point 340 K and allows observing the slipping surface (i.e., the contact between the two samples). By coupling: i) the rotary shear apparatus, ii) a video camera recording at 60 fps and a iii) laser pointer we observed the formation and evolution of a melt film that forms in the slipping surface after a phase of "dry" stick-slip. After each seismic event the melt layer solidify forming a pseudotachilite that partially welds the slipping surfaces. We also present the mechanical data that show rupture strengthening in

  2. ESF-X: a low-cost modular experiment computer for space flight experiments

    NASA Astrophysics Data System (ADS)

    Sell, Steven; Zapetis, Joseph; Littlefield, Jim; Vining, Joanne

    2004-08-01

    The high cost associated with spaceflight research often compels experimenters to scale back their research goals significantly purely for budgetary reasons; among experiment systems, control and data collection electronics are a major contributor to total project cost. ESF-X was developed as an architecture demonstration in response to this need: it is a highly capable, radiation-protected experiment support computer, designed to be configurable on demand to each investigator's particular experiment needs, and operational in LEO for missions lasting up to several years (e.g., ISS EXPRESS) without scheduled service or maintenance. ESF-X can accommodate up to 255 data channels (I/O, A/D, D/A, etc.), allocated per customer request, with data rates up to 40kHz. Additionally, ESF-X can be programmed using the graphical block-diagram based programming languages Simulink and MATLAB. This represents a major cost saving opportunity for future investigators, who can now obtain a customized, space-qualified experiment controller at steeply reduced cost compared to 'new' design, and without the performance compromises associated with using preexisting 'generic' systems. This paper documents the functional benchtop prototype, which utilizes a combination of COTS and space-qualified components, along with unit-gravity-specific provisions appropriate to laboratory environment evaluation of the ESF-X design concept and its physical implementation.

  3. Mechanization of and experience with a triplex fly-by-wire backup control system

    NASA Technical Reports Server (NTRS)

    Lock, W. P.; Petersen, W. R.; Whitman, G. B.

    1976-01-01

    A redundant three axis analog control system was designed and developed to back up a digital fly by wire control system for an F-8C airplane. The mechanization and operational experience with the backup control system, the problems involved in synchronizing it with the primary system, and the reliability of the system are discussed. The backup control system was dissimilar to the primary system, and it provided satisfactory handling through the flight envelope evaluated. Limited flight tests of a variety of control tasks showed that control was also satisfactory when the backup control system was controlled by a minimum displacement (force) side stick. The operational reliability of the F-8 digital fly by wire control system was satisfactory, with no unintentional downmodes to the backup control system in flight. The ground and flight reliability of the system's components is discussed.

  4. Modeling Ullage Dynamics of Tank Pressure Control Experiment during Jet Mixing in Microgravity

    NASA Technical Reports Server (NTRS)

    Kartuzova, O.; Kassemi, M.

    2016-01-01

    A CFD model for simulating the fluid dynamics of the jet induced mixing process is utilized in this paper to model the pressure control portion of the Tank Pressure Control Experiment (TPCE) in microgravity1. The Volume of Fluid (VOF) method is used for modeling the dynamics of the interface during mixing. The simulations were performed at a range of jet Weber numbers from non-penetrating to fully penetrating. Two different initial ullage positions were considered. The computational results for the jet-ullage interaction are compared with still images from the video of the experiment. A qualitative comparison shows that the CFD model was able to capture the main features of the interfacial dynamics, as well as the jet penetration of the ullage.

  5. Decompression experiments identify kinetic controls on explosive silicic eruptions

    USGS Publications Warehouse

    Mangan, M.T.; Sisson, T.W.; Hankins, W.B.

    2004-01-01

    Eruption intensity is largely controlled by decompression-induced release of water-rich gas dissolved in magma. It is not simply the amount of gas that dictates how forcefully magma is propelled upwards during an eruption, but also the rate of degassing, which is partly a function of the supersaturation pressure (??Pcritical) triggering gas bubble nucleation. High temperature and pressure decompression experiments using rhyolite and dacite melt reveal compositionally-dependent differences in the ??Pcritical of degassing that may explain why rhyolites have fueled some of the most explosive eruptions on record.

  6. Smart-device environmental control systems: experiences of people with cervical spinal cord injuries.

    PubMed

    Hooper, Bethany; Verdonck, Michele; Amsters, Delena; Myburg, Michelle; Allan, Emily

    2017-09-06

    Environmental control systems (ECS) are devices that enable people with severe physical limitations to independently control household appliances. Recent advancements in the area of environmental control technology have led to the development of ECS that can be controlled through mainstream smart-devices. There is limited research on ECS within Australia and no known research addressing smart-device ECS. The current study sought to explore users' experiences with smart-device ECS within Australia. The study followed a single embedded case study method. Participants (n = 5) were existing ECS users with a cervical spinal cord injury. Data were collected through semi-structured interviews with participants, reflexive journals and field notes. An inductive approach was used to analyze the data thematically. The experience of using a smart-device ECS presented both opportunities and costs to users. The opportunities included: independent control, choice, peace of mind, connection, effective resource use, and control over smart-phone functions and applications. The associated costs included: financial, time, frustration, and technical limitations. While findings are similar to previous research into traditional ECS this study indicates that smart-device ECS also offered a new opportunity for users to access mainstream smart-device functions and applications. Future research should investigate methods and resources that practitioners could utilize to better support new users of smart-device ECS. Implications for Rehabilitation As with traditional environmental control systems, users of smart environmental control systems report increased independence, choice and control. Smart-device environmental control systems provide users with access to mainstream smart-device functions and applications, which facilitate connection to family and the outside world. The costs to the user of smart-device environmental control systems include monetary and time investment, dealing

  7. Choice and Control within Family Relationships: The Lived Experience of Adults with Intellectual Disability

    ERIC Educational Resources Information Center

    Curryer, Bernadette; Stancliffe, Roger J.; Dew, Angela; Wiese, Michele Y.

    2018-01-01

    Increased choice and control is a driving force of current disability policy in Australia for people with disability and their families. Yet little is known of how adults with intellectual disability (ID) actually experience choice and control within their family relationships. We used interpretative phenomenological analysis of individual,…

  8. The Additive Coloration of Alkali Halides

    ERIC Educational Resources Information Center

    Jirgal, G. H.; and others

    1969-01-01

    Describes the construction and use of an inexpensive, vacuum furnace designed to produce F-centers in alkali halide crystals by additive coloration. The method described avoids corrosion or contamination during the coloration process. Examination of the resultant crystals is discussed and several experiments using additively colored crystals are…

  9. Caries experience among children with type 1 diabetes in Kuwait.

    PubMed

    Akpata, Enosakhare Samuel; Alomari, Qasem; Mojiminiyi, Olusequn A; Al-Sanae, Hala

    2012-01-01

    The purpose of this study was to determine the association among type 1 diabetes mellitus (DM), caries experience, and salivary glucose in 12- to 15-year-olds in Kuwait. A cross-sectional design was chosen involving 53 DM patients and 53 nondiabetic controls, group-matched by age and sex to the experimental group. The DM patients comprised 2 groups: (1) 14 controlled DM children (glycated haemoglobin, HbA1c=<8); and (2) 39 children with uncontrolled DM (HbA1c>8). The children's caries experience, at the precavitation and cavitation diagnostic threshold, was measured. In addition, their frequency of sugar consumption, plaque index, salivary flow rate, buffering capacity, as well as mutans streptococci, lactobacilli, and yeast counts were recorded. The DM children had significantly higher caries experience both at precavitation and cavitation diagnostic thresholds, than the control group. Multiple logistic regression analysis showed age, frequency of sugar consumption, and resting salivary flow rate to be significantly associated with high caries experience among the diabetic children. Caries experience was significantly higher in children with type 1 diabetes than in nondiabetic controls.

  10. Performance of an Additional Task During Level 2 Automated Driving: An On-Road Study Comparing Drivers With and Without Experience With Partial Automation.

    PubMed

    Solís-Marcos, Ignacio; Ahlström, Christer; Kircher, Katja

    2018-05-01

    To investigate the influence of prior experience with Level 2 automation on additional task performance during manual and Level 2 partially automated driving. Level 2 automation is now on the market, but its effects on driver behavior remain unclear. Based on previous studies, we could expect an increase in drivers' engagement in secondary tasks during Level 2 automated driving, but it is yet unknown how drivers will integrate all the ongoing demands in such situations. Twenty-one drivers (12 without, 9 with Level 2 automation experience) drove on a highway manually and with Level 2 automation (exemplified by Volvo Pilot Assist generation 2; PA2) while performing an additional task. In half of the conditions, the task could be interrupted (self-paced), and in the other half, it could not (system-paced). Drivers' visual attention, additional task performance, and other compensatory strategies were analyzed. Driving with PA2 led to decreased scores in the additional task and more visual attention to the dashboard. In the self-paced condition, all drivers looked more to the task and perceived a lower mental demand. The drivers experienced with PA2 used the system and the task more than the novice group and performed more overtakings. The additional task interfered more with Level 2 automation than with manual driving. The drivers, particularly the automation novice drivers, used some compensatory strategies. Automation designers need to consider these potential effects in the development of future automated systems.

  11. Solid film lubricants and thermal control coatings flown aboard the EOIM-3 MDA sub-experiment

    NASA Technical Reports Server (NTRS)

    Murphy, Taylor J.; David, Kaia E.; Babel, Hank W.

    1995-01-01

    Additional experimental data were desired to support the selection of candidate thermal control coatings and solid film lubricants for the McDonnell Douglas Aerospace (MDA) Space Station hardware. The third Evaluation of Oxygen Interactions With Materials Mission (EOIM-3) flight experiment presented an opportunity to study the effects of the low Earth orbit environment on thermal control coatings and solid film lubricants. MDA provided five solid film lubricants and two anodic thermal control coatings for EOIM-3. The lubricant sample set consisted of three solid film lubricants with organic binders one solid film lubricant with an inorganic binder, and one solid film lubricant with no binder. The anodize coating sample set consisted of undyed sulfuric acid anodize and cobalt sulfide dyed sulfuric acid anodize, each on two different substrate aluminum alloys. The organic and inorganic binders in the solid film lubricants experienced erosion, and the lubricating pigments experienced oxidation. MDA is continuing to assess the effect of exposure to the low Earth orbit environment on the life and friction properties of the lubricants. Results to date support the design practice of shielding solid film lubricants from the low Earth orbit environment. Post-flight optical property analysis of the anodized specimens indicated that there were limited contamination effects and some atomic oxygen and ultraviolet radiation effects. These effects appeared to be within the values predicted by simulated ground testing and analysis of these materials, and they were different for each coating and substrate.

  12. Importance of temperature control for HEFLEX, a biological experiment for Spacelab 1. [plant gravitational physiology study

    NASA Technical Reports Server (NTRS)

    Chapman, D. K.; Brown, A. H.

    1979-01-01

    The importance of temperature control to HEFLEX, a Spacelab experiment designed to measure kinetic properties of Helianthis nutation in a low-g environment, is discussed. It is argued that the development of the HEFLEX experiment has been severely hampered by the inadequate control of ambient air temperature provided by the spacecraft module design. A worst case calculation shows that delivery of only 69% of the maximum yield of useful data from the HEFLEX system is guaranteed; significant data losses from inadequate temperature control are expected. The magnitude of the expected data losses indicates that the cost reductions associated with imprecise temperature controls may prove to be a false economy in the long term.

  13. IN718 Additive Manufacturing Properties and Influences

    NASA Technical Reports Server (NTRS)

    Lambert, Dennis M.

    2015-01-01

    The results of tensile, fracture, and fatigue testing of IN718 coupons produced using the selective laser melting (SLM) additive manufacturing technique are presented. The data has been "generalized" to remove the numerical values, although certain references to material standards are provided. This document provides some knowledge of the effect of variation of controlled build parameters used in the SLM process, a snapshot of the capabilities of SLM in industry at present, and shares some of the lessons learned along the way. For the build parameter characterization, the parameters were varied over a range about the machine manufacturer's recommended value, and in each case they were varied individually, although some co-variance of those parameters would be expected. SLM-produced IN718, tensile, fracture, and high-cycle fatigue properties equivalent to wrought IN718 are achievable. Build and post-build processes need to be determined and then controlled to established limits to accomplish this. It is recommended that a multi-variable evaluation, e.g., design-of-experiment (DOE), of the build parameters be performed to better evaluate the co-variance of the parameters.

  14. Inflatable Antenna Experiment (IAE)

    NASA Image and Video Library

    1996-05-20

    S77-E-5022 (20 May 1996)--- Following its deployment from the Space Shuttle Endeavour, the Spartan 207/Inflatable Antenna Experiment (IAE) payload is backdropped over clouds and water. The view was photographed with an Electronic Still Camera (ESC) and downlinked to flight controllers on the first full day of orbital operations by the six-member crew. Managed by Goddard Space Flight Center (GSFC), Spartan is designed to provide short-duration, free-flight opportunities for a variety of scientific studies. The Spartan configuration on this flight is unique in that the IAE is part of an additional separate unit which is ejected once the experiment is completed. The IAE experiment will lay the groundwork for future technology development in inflatable space structures, which will be launched and then inflated like a balloon on-orbit.

  15. Inflatable Antenna Experiment (IAE)

    NASA Image and Video Library

    1996-05-20

    S77-E-5027 (20 May 1996)--- Following its deployment from the Space Shuttle Endeavour, the Spartan 207/Inflatable Antenna Experiment (IAE) payload is backdropped over clouds and water. The view was photographed with an Electronic Still Camera (ESC) and downlinked to flight controllers on the first full day of orbital operations by the six-member crew. Managed by Goddard Space Flight Center (GSFC), Spartan is designed to provide short-duration, free-flight opportunities for a variety of scientific studies. The Spartan configuration on this flight is unique in that the IAE is part of an additional separate unit which is ejected once the experiment is completed. The IAE experiment will lay the groundwork for future technology development in inflatable space structures, which will be launched and then inflated like a balloon on-orbit.

  16. Combination of antagonistic yeasts with two food additives for control of brown rot caused by Monilinia fructicola on sweet cherry fruit.

    PubMed

    Qin, G Z; Tian, S P; Xu, Y; Chan, Z L; Li, B Q

    2006-03-01

    To evaluate beneficial effect of two food additives, ammonium molybdate (NH4-Mo) and sodium bicarbonate (NaBi), on antagonistic yeasts for control of brown rot caused by Monilinia fructicola in sweet cherry fruit under various storage conditions. The mechanisms of action by which food additives enhance the efficacy of antagonistic yeasts were also evaluated. Biocontrol activity of Pichia membranefaciens and Cryptococcus laurentii against brown rot in sweet cherry fruit was improved by addition of 5 mmol l(-1) NH4-Mo or 2% NaBi when stored in air at 20 and 0 degrees C, and in controlled atmosphere (CA) storage with 10% O2 + 10% CO2 at 0 degrees C. Population dynamics of P. membranefaciens in the wounds of fruit were inhibited by NH4-Mo at 20 degrees C after 1 day of incubation and growth of C. laurentii was inhibited by NH4-Mo at 0 degrees C in CA storage after 60 days. In contrast, NaBi did not significantly influence growth of the two yeasts in fruit wounds under various storage conditions except that the growth of P. membranefaciens was stimulated after storage for 45 days at 0 degrees C in CA storage. When used alone, the two additives showed effective control of brown rot in sweet cherry fruit and the efficacy was closely correlated with the concentrations used. The result of in vitro indicated that growth of M. fructicola was significantly inhibited by NH4-Mo and NaBi. Application of additives improved biocontrol of brown rot on sweet cherry fruit under various storage conditions. It is postulated that the enhancement of disease control is directly because of the inhibitory effects of additives on pathogen growth, and indirectly because of the relatively little influence of additives on the growth of antagonistic yeasts. The results obtained in this study suggest that an integration of NH4-Mo or NaBi with biocontrol agents has great potential in commercial management of postharvest diseases of fruit.

  17. Color Addition and Subtraction Apps

    NASA Astrophysics Data System (ADS)

    Ruiz, Frances; Ruiz, Michael J.

    2015-10-01

    Color addition and subtraction apps in HTML5 have been developed for students as an online hands-on experience so that they can more easily master principles introduced through traditional classroom demonstrations. The evolution of the additive RGB color model is traced through the early IBM color adapters so that students can proceed step by step in understanding mathematical representations of RGB color. Finally, color addition and subtraction are presented for the X11 colors from web design to illustrate yet another real-life application of color mixing.

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

    NASA Technical Reports Server (NTRS)

    Gilbert, D. W.

    1973-01-01

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

  19. Experiments in teleoperator and autonomous control of space robotic vehicles

    NASA Technical Reports Server (NTRS)

    Alexander, Harold L.

    1991-01-01

    A program of research embracing teleoperator and automatic navigational control of freely flying satellite robots is presented. Current research goals include: (1) developing visual operator interfaces for improved vehicle teleoperation; (2) determining the effects of different visual interface system designs on operator performance; and (3) achieving autonomous vision-based vehicle navigation and control. This research program combines virtual-environment teleoperation studies and neutral-buoyancy experiments using a space-robot simulator vehicle currently under development. Visual-interface design options under investigation include monoscopic versus stereoscopic displays and cameras, helmet-mounted versus panel-mounted display monitors, head-tracking versus fixed or manually steerable remote cameras, and the provision of vehicle-fixed visual cues, or markers, in the remote scene for improved sensing of vehicle position, orientation, and motion.

  20. Flight experience with a fail-operational digital fly-by-wire control system

    NASA Technical Reports Server (NTRS)

    Brown, S. R.; Szalai, K. J.

    1977-01-01

    The NASA Dryden Flight Research Center is flight testing a triply redundant digital fly-by-wire (DFBW) control system installed in an F-8 aircraft. The full-time, full-authority system performs three-axis flight control computations, including stability and command augmentation, autopilot functions, failure detection and isolation, and self-test functions. Advanced control law experiments include an active flap mode for ride smoothing and maneuver drag reduction. This paper discusses research being conducted on computer synchronization, fault detection, fault isolation, and recovery from transient faults. The F-8 DFBW system has demonstrated immunity from nuisance fault declarations while quickly identifying truly faulty components.

  1. Control of membrane fouling with the addition of a nanoporous zeolite membrane fouling reducer to the submerged hollow fiber membrane bioreactor.

    PubMed

    Park, Chul-Hwi; Park, Jun-Won; Han, Gee-Bong

    2016-10-14

    The membrane fouling control via the addition of nanoporous zeolite membrane fouling reducer (Z-MFR) to the submerged membrane bioreactor (MBR) was investigated. Using scanning electron microscopy/energy-dispersive X-ray (SEM/EDX) analysis techniques, the characteristics of fouling on a hollow fiber membrane surface were also analyzed. The addition of Z-MFR to the MBR led to the adsorption of foulants and the flocculation of mixed liquor suspended solids (MLSSs), which resulted in substantially enhancing the membrane filterability. The critical flux values obtained from the sewage mixed liquors of 3400 mg L(-1) at the effective dosage rate of 0.03 mg Z-MFR mg(-1) MLSS was 85 L m(-2) h(-1) (LMH), which was enhanced by 42%. The transmembrane pressure (TMP) variation under the operating conditions of 30 LMH with 3500 mg MLSS L(-1) showed that the addition of Z-MFR extended the time required to reach the critical flux of 0.32 bar by 2.6-fold longer than the control. Thus, due to the hybrid functions of adsorbing foulants and precipitating colloidal substances with the addition of Z-MFR, a decrease in the foulant amount and an improvement of sludge flocculation have been attained simultaneously. As a result, the membrane fouling control was achieved effectively with the addition of the Z-MFR.

  2. Building adaptive connectionist-based controllers: review of experiments in human-robot interaction, collective robotics, and computational neuroscience

    NASA Astrophysics Data System (ADS)

    Billard, Aude

    2000-10-01

    This paper summarizes a number of experiments in biologically inspired robotics. The common feature to all experiments is the use of artificial neural networks as the building blocks for the controllers. The experiments speak in favor of using a connectionist approach for designing adaptive and flexible robot controllers, and for modeling neurological processes. I present 1) DRAMA, a novel connectionist architecture, which has general property for learning time series and extracting spatio-temporal regularities in multi-modal and highly noisy data; 2) Robota, a doll-shaped robot, which imitates and learns a proto-language; 3) an experiment in collective robotics, where a group of 4 to 15 Khepera robots learn dynamically the topography of an environment whose features change frequently; 4) an abstract, computational model of primate ability to learn by imitation; 5) a model for the control of locomotor gaits in a quadruped legged robot.

  3. Tools for controlling protein interactions with light

    PubMed Central

    Tucker, Chandra L.; Vrana, Justin D.; Kennedy, Matthew J.

    2014-01-01

    Genetically-encoded actuators that allow control of protein-protein interactions with light, termed ‘optical dimerizers’, are emerging as new tools for experimental biology. In recent years, numerous new and versatile dimerizer systems have been developed. Here we discuss the design of optical dimerizer experiments, including choice of a dimerizer system, photoexcitation sources, and coordinate use of imaging reporters. We provide detailed protocols for experiments using two dimerization systems we previously developed, CRY2/CIB and UVR8/UVR8, for use controlling transcription, protein localization, and protein secretion with light. Additionally, we provide instructions and software for constructing a pulse-controlled LED light device for use in experiments requiring extended light treatments. PMID:25181301

  4. Effect of enzyme addition on the nutritive value of high oleic acid sunflower seeds in chicken diets.

    PubMed

    Brenes, A; Centeno, C; Viveros, A; Arija, I

    2008-11-01

    Two experiments were conducted to evaluate the effects of enzyme addition in chicken diets containing high oleic acid sunflower seeds (HOASS). In the first experiment (4 to 21 d of age), enzyme addition (lipase, phospholipase, and a combination of these) was used at the inclusion level of 1 g/kg in diets containing HOASS (250 g/kg) compared with a control corn-soybean diet. Weight gain, feed consumption, relative liver weight, fat digestibility, and amylase, lipase, serum lactate dehydrogenase (LDH), and creatine phosphokinase (CPK) activities were reduced, and feed conversion, relative duodenum, jejunum, ileum, and ceca lengths, plasma uric acid, cholesterol, and glucose concentrations were increased in the unsupplemented HOASS diet compared with the control diet. The addition of enzymes to the HOASS diet increased weight gain, feed consumption, relative pancreas and liver weights, fat digestibility, amylase and lipase activities, plasma uric acid, calcium, serum LDH and CPK, and total protein concentration and reduced feed conversion, relative spleen weight, relative duodenum, jejunum, ileum, and ceca lengths, plasma cholesterol, and glucose compared with the unsupplemented HOASS diet. In the second experiment (0 to 21 d of age), the same enzymes (0.5 g/kg each) were included in diets containing 150 g/kg of HOASS compared with a conventional sunflower meal diet (150 g/kg). The HOASS diet did not affect performance but reduced relative pancreas and abdominal fat weights and relative duodenum and ceca lengths, and increased crude fat, CP, and essential and nonessential amino acid digestibilities (except Ser, which was reduced) compared with the control diet. The addition of enzymes in the HOASS diet increased weight gain, feed consumption, and relative pancreas weight and reduced feed conversion, CP, and essential and nonessential amino acid digestibilities compared with the unsupplemented HOASS diet. In conclusion, the addition of 250 g of HOASS/kg in the diets

  5. Data Analysis for the NASA/Boeing Hybrid Laminar Flow Control Crossflow Experiment

    NASA Technical Reports Server (NTRS)

    Eppink, Jenna L.; Wlezien, Richard

    2011-01-01

    The Hybrid-Laminar Flow Control (HLFC) Crossflow Experiment, completed in 1995. generated a large database of boundary layer stability and transition data that was only partially analyzed before data analysis was abruptly ended in the late 1990's. Renewed interest in laminar flow technologies prompted additional data analysis, to integrate all data, including some post-test roughness and porosity measurements. The objective is to gain new insights into the effects of suction on boundary layer stability. A number of challenges were encountered during the data analysis, and their solutions are discussed in detail. They include the effect of the probe vibration, the effect of the time-varying surface temperature on traveling crossflow instabilities, and the effect of the stationary crossflow modes on the approximation of wall location. Despite the low turbulence intensity of the wind tunnel (0.01 to 0.02%), traveling crosflow disturbances were present in the data, in some cases at amplitudes up to 1% of the freestream velocity. However, the data suggests that transition was dominated by stationary crossflow. Traveling crossflow results and stationary data in the presence of suction are compared with linear parabolized stability equations results as a way of testing the quality of the results.

  6. Interpreting large-scale experiments on effects of trawling on benthic fauna: an empirical test of the potential effects of spatial confounding in experiments without replicated control and trawled areas.

    PubMed

    Lindegarth; Valentinsson; Hansson; Ulmestrand

    2000-03-15

    Disturbances due to trawling and dredging is a serious threat to assemblages of benthic marine animals. We tested hypotheses about effects of trawling on benthic assemblages in a manipulative field experiment, using gear and intensities relevant to future management of trawling in a Swedish fjord. Three trawled and three control sites were sampled at several times before and after trawling was initiated. This paper describes how conclusions about effects of trawling might differ between experiments involving replicate sites and experiments using only one trawled and one control site, as in several recent studies. Analyses of selected taxa showed that abundances of many species changed differently among control sites. Differences in temporal change between pairs of single trawled and control sites were also frequent. Neither the quantitative nor the qualitative nature of differences between treatments could, however, be coherently interpreted among the different combinations of trawled and control sites. This is consistent with results obtained from analyses using all sites, which showed no consistent effects of trawling on any of these taxa. These results provide empirical evidence that spatial confounding may cause serious problems to formal interpretation of experiments, which use only one control and one trawled area. Such potential problems can best be solved by ensuring that the study incorporates more than one control site.

  7. [Evaluation on the application of the mouse nicotine toxicity experiment in tobacco control among adolescents].

    PubMed

    Wen, Xiaozhong; Chen, Weiqing; Liang, Caihua; Qiu, Quan

    2007-07-01

    To explore the application of the mouse nicotine toxicity experiment in tobacco control among adolescents. A cross-sectional survey was conducted among 1626 students of three secondary schools with self-administered questionnaires three months after the intervention. The measurements of the student' s evaluation included their response, confidence and support to the experiment. Among the respondents, 87.4% had interest in the experiment and 84.0% had perceived its impact. The mouse nicotine toxicity experiment was attracted by greater interest from the students and was strong perceived by impact on them, when compared with the multi-media and the textbook. There were statistically significant (P < 0.001) difference in students' response between the three interventions. And 85.5% of the students believed that nicotine could be similar effects on the human body and 83.7% thought that the experiment could educate middle school students refuse smoking. Among the students, 76.4% agreed to show this kind of animal experiments to middle school students but 9.4% objected. 843 (51.9%) students were willing to do the experiment by themselves. The grade 7 students had lower response and confidence to the experiment than grade 8 students (P < 0.05). The evaluation on the experiment were significant (P < 0.05) different among the students in three smoking stages: non-smokers more than irregular smokers more than regular smokers. The mouse nicotine toxicity experiment was believed by most students and could get great support from them. It could deserve wider application in school-based tobacco control programs.

  8. Development and flight test experiences with a flight-crucial digital control system

    NASA Technical Reports Server (NTRS)

    Mackall, Dale A.

    1988-01-01

    Engineers and scientists in the advanced fighter technology integration (AFTI) F-16 program investigated the integration of emerging technologies into an advanced fighter aircraft. AFTI's three major technologies included: flight-crucial digital control, decoupled aircraft flight control, and integration of avionics, flight control, and pilot displays. In addition to investigating improvements in fighter performance, researchers studied the generic problems confronting the designers of highly integrated flight-crucial digital control. An overview is provided of both the advantages and problems of integration digital control systems. Also, an examination of the specification, design, qualification, and flight test life-cycle phase is provided. An overview is given of the fault-tolerant design, multimoded decoupled flight control laws, and integrated avionics design. The approach to qualifying the software and system designs is discussed, and the effects of design choices on system qualification are highlighted.

  9. Online measurement of bead geometry in GMAW-based additive manufacturing using passive vision

    NASA Astrophysics Data System (ADS)

    Xiong, Jun; Zhang, Guangjun

    2013-11-01

    Additive manufacturing based on gas metal arc welding is an advanced technique for depositing fully dense components with low cost. Despite this fact, techniques to achieve accurate control and automation of the process have not yet been perfectly developed. The online measurement of the deposited bead geometry is a key problem for reliable control. In this work a passive vision-sensing system, comprising two cameras and composite filtering techniques, was proposed for real-time detection of the bead height and width through deposition of thin walls. The nozzle to the top surface distance was monitored for eliminating accumulated height errors during the multi-layer deposition process. Various image processing algorithms were applied and discussed for extracting feature parameters. A calibration procedure was presented for the monitoring system. Validation experiments confirmed the effectiveness of the online measurement system for bead geometry in layered additive manufacturing.

  10. Michael Additions of Highly Basic Enolates to ortho-Quinone Methides

    PubMed Central

    Lewis, Robert S.; Garza, Christopher J.; Dang, Ann T.; Pedro, Te Kie A.; Chain, William J.

    2015-01-01

    A protocol by which ketone or ester enolates and ortho-quinone methides (o-QMs) are generated in situ in a single reaction flask from silylated precursors under the action of anhydrous fluoride is reported. The reaction partners are joined to give a variety of β-(2-hydroxyphenyl)-carbonyl compounds in 32–94% yield in a single laboratory operation. The intermediacy of o-QMs is supported by control experiments utilizing enolate precursors and conventional alkyl halides as competitive alkylating agents and the isolation of 1,5-dicarbonyl products resulting from conjugate additions that do not restore the aromatic system. PMID:25906358

  11. Exhaustion Experiences in Junior Athletes: The Importance of Motivation and Self-Control Competencies.

    PubMed

    Jordalen, Gro; Lemyre, Pierre-Nicolas; Durand-Bush, Natalie

    2016-01-01

    Quality of motivation, self-control competencies, as well as past performance experience influence sport participation outcomes in developing athletes. Studies have shown that junior athletes high in self-determined motivation are less prone to experience burnout, while self-control competencies help developing athletes to be conscious and deliberate in their self-regulatory efforts toward elite sport performances and avoid negative sport participation outcomes. Combining the self-determination theory framework and psychosocial theories of self-regulation, the aim of this cross-sectional study was to examine how various types of motivation and self-control competencies together are associated with the development of burnout symptoms in junior athletes. High-level Norwegian winter-sport athletes from elite sport academies ( N = 199; female n = 72; 16-20 years of age) consented to participate. Associations between six types of motivational regulation, self-control, and indices of exhaustion were investigated. We hypothesized that athletes' self-control competencies are important to operate successfully, and influenced by different types of motivation, they are expected to help athletes avoid negative sport participation outcomes such as emotional and physical exhaustion. Structural equation modeling analyses were conducted to analyze these relationships, and results revealed some multifaceted associations. When identifying antecedents of sport participation exhaustion and burnout, there is a need to go beyond the unique framework of motivation theories, and explore what cognitive competencies ensure fulfillment of motivation desires. In the current study, differences in junior athletes' quality of motivation influenced self-control competencies when predicting exhaustion. Interestingly, young athletes driven by self-determined (intrinsic, integrated, and identified), and controlled (introjected and amotivation) regulations in association with self-control offered the

  12. Mechanization of and experience with a triplex fly-by-wire backup control system

    NASA Technical Reports Server (NTRS)

    Lock, W. P.; Petersen, W. R.; Whitman, G. B.

    1975-01-01

    A redundant three-axis analog control system was designed and developed to back up a digital fly-by-wire control system for an F-8C airplane. Forty-two flights, involving 58 hours of flight time, were flown by six pilots. The mechanization and operational experience with the backup control system, the problems involved in synchronizing it with the primary system, and the reliability of the system are discussed. The backup control system was dissimilar to the primary system, and it provided satisfactory handling through the flight envelope evaluated. Limited flight tests of a variety of control tasks showed that control was also satisfactory when the backup control system was controlled by a minimum-displacement (force) side stick. The operational reliability of the F-8 digital fly-by-wire control system was satisfactory, with no unintentional downmodes to the backup control system in flight. The ground and flight reliability of the system's components is discussed.

  13. Adaptive Controller Effects on Pilot Behavior

    NASA Technical Reports Server (NTRS)

    Trujillo, Anna C.; Gregory, Irene M.; Hempley, Lucas E.

    2014-01-01

    Adaptive control provides robustness and resilience for highly uncertain, and potentially unpredictable, flight dynamics characteristic. Some of the recent flight experiences of pilot-in-the-loop with an adaptive controller have exhibited unpredicted interactions. In retrospect, this is not surprising once it is realized that there are now two adaptive controllers interacting, the software adaptive control system and the pilot. An experiment was conducted to categorize these interactions on the pilot with an adaptive controller during control surface failures. One of the objectives of this experiment was to determine how the adaptation time of the controller affects pilots. The pitch and roll errors, and stick input increased for increasing adaptation time and during the segment when the adaptive controller was adapting. Not surprisingly, altitude, cross track and angle deviations, and vertical velocity also increase during the failure and then slowly return to pre-failure levels. Subjects may change their behavior even as an adaptive controller is adapting with additional stick inputs. Therefore, the adaptive controller should adapt as fast as possible to minimize flight track errors. This will minimize undesirable interactions between the pilot and the adaptive controller and maintain maneuvering precision.

  14. Performance experiments with alternative advanced teleoperator control modes for a simulated solar maximum satellite repair

    NASA Technical Reports Server (NTRS)

    Das, H.; Zak, H.; Kim, W. S.; Bejczy, A. K.; Schenker, P. S.

    1992-01-01

    Experiments are described which were conducted at the JPL Advanced Teleoperator Lab to demonstrate and evaluate the effectiveness of various teleoperator control modes in the performance of a simulated Solar Max Satellite Repair (SMSR) task. THe SMSR was selected as a test because it is very rich in performance capability requirements and it actually has been performed by two EVA astronauts in the Space Shuttle Bay in 1984. The main subtasks are: thermal blanket removal; installation of a hinge attachment for electrical panel opening; opening of electrical panel; removal of electrical connectors; relining of cable bundles; replacement of electrical panel; securing parts and cables; re-mate electrical connectors; closing of electrical panel; and reinstating thermal blanket. The current performance experiments are limited to thermal blanket cutting, electrical panel unbolting and handling electrical bundles and connectors. In one formal experiment even different control modes were applied to the unbolting and reinsertion of electrical panel screws subtasks. The seven control modes are alternative combinations of manual position and rate control with force feedback and remote compliance referenced to force-torque sensor information. Force-torque sensor and end effector position data and task completion times were recorded for analysis and quantification of operator performance.

  15. Integrated Controlling System and Unified Database for High Throughput Protein Crystallography Experiments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gaponov, Yu.A.; Igarashi, N.; Hiraki, M.

    2004-05-12

    An integrated controlling system and a unified database for high throughput protein crystallography experiments have been developed. Main features of protein crystallography experiments (purification, crystallization, crystal harvesting, data collection, data processing) were integrated into the software under development. All information necessary to perform protein crystallography experiments is stored (except raw X-ray data that are stored in a central data server) in a MySQL relational database. The database contains four mutually linked hierarchical trees describing protein crystals, data collection of protein crystal and experimental data processing. A database editor was designed and developed. The editor supports basic database functions to view,more » create, modify and delete user records in the database. Two search engines were realized: direct search of necessary information in the database and object oriented search. The system is based on TCP/IP secure UNIX sockets with four predefined sending and receiving behaviors, which support communications between all connected servers and clients with remote control functions (creating and modifying data for experimental conditions, data acquisition, viewing experimental data, and performing data processing). Two secure login schemes were designed and developed: a direct method (using the developed Linux clients with secure connection) and an indirect method (using the secure SSL connection using secure X11 support from any operating system with X-terminal and SSH support). A part of the system has been implemented on a new MAD beam line, NW12, at the Photon Factory Advanced Ring for general user experiments.« less

  16. A Tuneable Switch for Controlling Environmental Degradation of Bioplastics: Addition of Isothiazolinone to Polyhydroxyalkanoates

    PubMed Central

    Woolnough, Catherine Anne; Yee, Lachlan Hartley; Charlton, Timothy Stuart; Foster, Leslie John Ray

    2013-01-01

    Controlling the environmental degradation of polyhydroxybutyrate (PHB) and polyhydroxyvalerate (P(HB-co-HV)) bioplastics would expand the range of their potential applications. Combining PHB and P(HB-co-HV) films with the anti-fouling agent 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (DCOI, <10% w/w) restricted microbial colonisation in soil, but did not significantly affect melting temperature or the tensile strength of films. DCOI films showed reduced biofouling and postponed the onset of weight loss by up to 100 days, a 10-fold increase compared to unmodified films where the microbial coverage was significant. In addition, the rate of PHA-DCOI weight loss, post-onset, reduced by about 150%; in contrast a recorded weight loss of only 0.05% per day for P(HB-co-HV) with a 10% DCOI loading was observed. This is in stark contrast to the unmodified PHB film, where a recorded weight loss of only 0.75% per day was made. The ‘switch’ that initiates film weight loss, and its subsequent reduced rate, depended on the DCOI loading to control biofouling. The control of biofouling and environmental degradation for these DCOI modified bioplastics increases their potential use in biodegradable applications. PMID:24146779

  17. A new RISE-based adaptive control of PKMs: design, stability analysis and experiments

    NASA Astrophysics Data System (ADS)

    Bennehar, M.; Chemori, A.; Bouri, M.; Jenni, L. F.; Pierrot, F.

    2018-03-01

    This paper deals with the development of a new adaptive control scheme for parallel kinematic manipulators (PKMs) based on Rrbust integral of the sign of the error (RISE) control theory. Original RISE control law is only based on state feedback and does not take advantage of the modelled dynamics of the manipulator. Consequently, the overall performance of the resulting closed-loop system may be poor compared to modern advanced model-based control strategies. We propose in this work to extend RISE by including the nonlinear dynamics of the PKM in the control loop to improve its overall performance. More precisely, we augment original RISE control scheme with a model-based adaptive control term to account for the inherent nonlinearities in the closed-loop system. To demonstrate the relevance of the proposed controller, real-time experiments are conducted on the Delta robot, a three-degree-of-freedom (3-DOF) PKM.

  18. Optimal feedback control successfully explains changes in neural modulations during experiments with brain-machine interfaces.

    PubMed

    Benyamini, Miri; Zacksenhouse, Miriam

    2015-01-01

    Recent experiments with brain-machine-interfaces (BMIs) indicate that the extent of neural modulations increased abruptly upon starting to operate the interface, and especially after the monkey stopped moving its hand. In contrast, neural modulations that are correlated with the kinematics of the movement remained relatively unchanged. Here we demonstrate that similar changes are produced by simulated neurons that encode the relevant signals generated by an optimal feedback controller during simulated BMI experiments. The optimal feedback controller relies on state estimation that integrates both visual and proprioceptive feedback with prior estimations from an internal model. The processing required for optimal state estimation and control were conducted in the state-space, and neural recording was simulated by modeling two populations of neurons that encode either only the estimated state or also the control signal. Spike counts were generated as realizations of doubly stochastic Poisson processes with linear tuning curves. The model successfully reconstructs the main features of the kinematics and neural activity during regular reaching movements. Most importantly, the activity of the simulated neurons successfully reproduces the observed changes in neural modulations upon switching to brain control. Further theoretical analysis and simulations indicate that increasing the process noise during normal reaching movement results in similar changes in neural modulations. Thus, we conclude that the observed changes in neural modulations during BMI experiments can be attributed to increasing process noise associated with the imperfect BMI filter, and, more directly, to the resulting increase in the variance of the encoded signals associated with state estimation and the required control signal.

  19. Optimal feedback control successfully explains changes in neural modulations during experiments with brain-machine interfaces

    PubMed Central

    Benyamini, Miri; Zacksenhouse, Miriam

    2015-01-01

    Recent experiments with brain-machine-interfaces (BMIs) indicate that the extent of neural modulations increased abruptly upon starting to operate the interface, and especially after the monkey stopped moving its hand. In contrast, neural modulations that are correlated with the kinematics of the movement remained relatively unchanged. Here we demonstrate that similar changes are produced by simulated neurons that encode the relevant signals generated by an optimal feedback controller during simulated BMI experiments. The optimal feedback controller relies on state estimation that integrates both visual and proprioceptive feedback with prior estimations from an internal model. The processing required for optimal state estimation and control were conducted in the state-space, and neural recording was simulated by modeling two populations of neurons that encode either only the estimated state or also the control signal. Spike counts were generated as realizations of doubly stochastic Poisson processes with linear tuning curves. The model successfully reconstructs the main features of the kinematics and neural activity during regular reaching movements. Most importantly, the activity of the simulated neurons successfully reproduces the observed changes in neural modulations upon switching to brain control. Further theoretical analysis and simulations indicate that increasing the process noise during normal reaching movement results in similar changes in neural modulations. Thus, we conclude that the observed changes in neural modulations during BMI experiments can be attributed to increasing process noise associated with the imperfect BMI filter, and, more directly, to the resulting increase in the variance of the encoded signals associated with state estimation and the required control signal. PMID:26042002

  20. Everyday temptations: an experience sampling study of desire, conflict, and self-control.

    PubMed

    Hofmann, Wilhelm; Baumeister, Roy F; Förster, Georg; Vohs, Kathleen D

    2012-06-01

    How often and how strongly do people experience desires, to what extent do their desires conflict with other goals, and how often and successfully do people exercise self-control to resist their desires? To investigate desire and attempts to control desire in everyday life, we conducted a large-scale experience sampling study based on a conceptual framework integrating desire strength, conflict, resistance (use of self-control), and behavior enactment. A sample of 205 adults wore beepers for a week. They furnished 7,827 reports of desire episodes and completed personality measures of behavioral inhibition system/behavior activation system (BIS/BAS) sensitivity, trait self-control, perfectionism, and narcissistic entitlement. Results suggest that desires are frequent, variable in intensity, and largely unproblematic. Those urges that do conflict with other goals tend to elicit resistance, with uneven success. Desire strength, conflict, resistance, and self-regulatory success were moderated in multiple ways by personality variables as well as by situational and interpersonal factors such as alcohol consumption, the mere presence of others, and the presence of others who already had enacted the desire in question. Whereas personality generally had a stronger impact on the dimensions of desire that emerged early in its course (desire strength and conflict), situational factors showed relatively more influence on components later in the process (resistance and behavior enactment). In total, these findings offer a novel and detailed perspective on the nature of everyday desires and associated self-regulatory successes and failures. 2012 APA, all rights reserved

  1. Touch sensors and control.

    NASA Technical Reports Server (NTRS)

    Hill, J. W.; Sword, A. J.

    1973-01-01

    Description of the equipment employed and results obtained in experiments with tactile feedback and different levels of automatic control. In the experiments described tactile feedback was investigated by incorporating a touch sensing and touch display system into a teleoperator, while the levels of automatic control were investigated by incorporating supervisory control features in the teleoperator control system. In particular, a hand contact system which senses and reproduces to the operator the contact between the end-effector and the object being touched or manipulated is described, as well as a jaw contact system which senses and reproduces to the operator the shape and location of the object held in the remote jaws, and an arm control system consisting of a control station where the operator controls the motion of the arm by transmitting commands, a remote station that accepts the commands and uses them, and a communications link that limits information flow. In addition, an algorithmic language for remote manipulation is described, and the desired features that an automatic arm controller should possess are reviewed.

  2. NASA Controller Acceptability Study 1(CAS-1) Experiment Description and Initial Observations

    NASA Technical Reports Server (NTRS)

    Chamberlain, James P.; Consiglio, Maria C.; Comstock, James R., Jr.; Ghatas, Rania W.; Munoz, Cesar

    2015-01-01

    This paper describes the Controller Acceptability Study 1 (CAS-1) experiment that was conducted by NASA Langley Research Center personnel from January through March 2014 and presents partial CAS-1 results. CAS-1 employed 14 air traffic controller volunteers as research subjects to assess the viability of simulated future unmanned aircraft systems (UAS) operating alongside manned aircraft in moderate-density, moderate-complexity Class E airspace. These simulated UAS were equipped with a prototype pilot-in-the-loop (PITL) Detect and Avoid (DAA) system, specifically the Self-Separation (SS) function of such a system based on Stratway+ software to replace the see-and-avoid capabilities of manned aircraft pilots. A quantitative CAS-1 objective was to determine horizontal miss distance (HMD) values for SS encounters that were most acceptable to air traffic controllers, specifically HMD values that were assessed as neither unsafely small nor disruptively large. HMD values between 0.5 and 3.0 nautical miles (nmi) were assessed for a wide array of encounter geometries between UAS and manned aircraft. The paper includes brief introductory material about DAA systems and their SS functions, followed by descriptions of the CAS-1 simulation environment, prototype PITL SS capability, and experiment design, and concludes with presentation and discussion of partial CAS-1 data and results.

  3. Initial experiments on the end-point control of a flexible one-link robot

    NASA Technical Reports Server (NTRS)

    Cannon, R. H., Jr.; Schmitz, E.

    1984-01-01

    The present investigation is concerned with initial experiments regarding a specific unsolved control problem which appeared to be central to advances in the art of robotics. This problem involves the control of a flexible member (one link of a robot system). The position of the end-effector, called the end point or tip, is controlled by measuring that position and using the measurement as a basis for applying control torque to the other end of the flexible member, as for instance, the robot's elbow joint. A description is presented of the features of the first experimental arm which has been made, and an outline is provided of the general strategy for controlling it using its tip sensor and shoulder torquer.

  4. Emulation-Based Virtual Laboratories: A Low-Cost Alternative to Physical Experiments in Control Engineering Education

    ERIC Educational Resources Information Center

    Goodwin, G. C.; Medioli, A. M.; Sher, W.; Vlacic, L. B.; Welsh, J. S.

    2011-01-01

    This paper argues the case for emulation-based virtual laboratories in control engineering education. It demonstrates that such emulation experiments can give students an industrially relevant educational experience at relatively low cost. The paper also describes a particular emulation-based system that has been developed with the aim of giving…

  5. CONTROL ROD ALLOY CONTAINING NOBLE METAL ADDITIONS

    DOEpatents

    Anderson, W.K.; Ray, W.E.

    1960-05-01

    Silver-base alloys suitable for use in the fabrication of control rods for neutronic reactors are given. The alloy consists of from 0.5 wt.% to about 1.5 wt.% of a noble metal of platinum, ruthenium, rhodium, osmium, or palladium, up to 10 wt.% of cadmium, from 2 to 20 wt.% indium, the balance being silver.

  6. Turbulence and Cavitation Suppression by Quaternary Ammonium Salt Additives.

    PubMed

    Naseri, Homa; Trickett, Kieran; Mitroglou, Nicholas; Karathanassis, Ioannis; Koukouvinis, Phoevos; Gavaises, Manolis; Barbour, Robert; Diamond, Dale; Rogers, Sarah E; Santini, Maurizio; Wang, Jin

    2018-05-16

    We identify the physical mechanism through which newly developed quaternary ammonium salt (QAS) deposit control additives (DCAs) affect the rheological properties of cavitating turbulent flows, resulting in an increase in the volumetric efficiency of clean injectors fuelled with diesel or biodiesel fuels. Quaternary ammonium surfactants with appropriate counterions can be very effective in reducing the turbulent drag in aqueous solutions, however, less is known about the effect of such surfactants in oil-based solvents or in cavitating flow conditions. Small-angle neutron scattering (SANS) investigations show that in traditional DCA fuel compositions only reverse spherical micelles form, whereas reverse cylindrical micelles are detected by blending the fuel with the QAS additive. Moreover, experiments utilising X-ray micro computed tomography (micro-CT) in nozzle replicas, quantify that in cavitation regions the liquid fraction is increased in the presence of the QAS additive. Furthermore, high-flux X-ray phase contrast imaging (XPCI) measurements identify a flow stabilization effect in the region of vortex cavitation by the QAS additive. The effect of the formation of cylindrical micelles is reproduced with computational fluid dynamics (CFD) simulations by including viscoelastic characteristics for the flow. It is demonstrated that viscoelasticity can reduce turbulence and suppress cavitation, and subsequently increase the injector's volumetric efficiency.

  7. Inflatable Antenna Experiment (IAE)

    NASA Image and Video Library

    1996-05-20

    S77-E-5033 (20 May 1996) --- Following its deployment from the Space Shuttle Endeavour, the Spartan 207/Inflatable Antenna Experiment (IAE) payload is backdropped against a wall of grayish clouds. The view was photographed with an Electronic Still Camera (ESC) and downlinked to flight controllers on the first full day of orbital operations by the six-member crew. Managed by Goddard Space Flight Center (GSFC), Spartan is designed to provide short-duration, free-flight opportunities for a variety of scientific studies. The Spartan configuration on this flight is unique in that the IAE is part of an additional separate unit which is ejected once the experiment is completed. The IAE experiment will lay the groundwork for future technology development in inflatable space structures, which will be launched and then inflated like a balloon on-orbit.

  8. A distributed, graphical user interface based, computer control system for atomic physics experiments

    NASA Astrophysics Data System (ADS)

    Keshet, Aviv; Ketterle, Wolfgang

    2013-01-01

    Atomic physics experiments often require a complex sequence of precisely timed computer controlled events. This paper describes a distributed graphical user interface-based control system designed with such experiments in mind, which makes use of off-the-shelf output hardware from National Instruments. The software makes use of a client-server separation between a user interface for sequence design and a set of output hardware servers. Output hardware servers are designed to use standard National Instruments output cards, but the client-server nature should allow this to be extended to other output hardware. Output sequences running on multiple servers and output cards can be synchronized using a shared clock. By using a field programmable gate array-generated variable frequency clock, redundant buffers can be dramatically shortened, and a time resolution of 100 ns achieved over effectively arbitrary sequence lengths.

  9. A distributed, graphical user interface based, computer control system for atomic physics experiments.

    PubMed

    Keshet, Aviv; Ketterle, Wolfgang

    2013-01-01

    Atomic physics experiments often require a complex sequence of precisely timed computer controlled events. This paper describes a distributed graphical user interface-based control system designed with such experiments in mind, which makes use of off-the-shelf output hardware from National Instruments. The software makes use of a client-server separation between a user interface for sequence design and a set of output hardware servers. Output hardware servers are designed to use standard National Instruments output cards, but the client-server nature should allow this to be extended to other output hardware. Output sequences running on multiple servers and output cards can be synchronized using a shared clock. By using a field programmable gate array-generated variable frequency clock, redundant buffers can be dramatically shortened, and a time resolution of 100 ns achieved over effectively arbitrary sequence lengths.

  10. Data exploration, quality control and statistical analysis of ChIP-exo/nexus experiments

    PubMed Central

    Welch, Rene; Chung, Dongjun; Grass, Jeffrey; Landick, Robert

    2017-01-01

    Abstract ChIP-exo/nexus experiments rely on innovative modifications of the commonly used ChIP-seq protocol for high resolution mapping of transcription factor binding sites. Although many aspects of the ChIP-exo data analysis are similar to those of ChIP-seq, these high throughput experiments pose a number of unique quality control and analysis challenges. We develop a novel statistical quality control pipeline and accompanying R/Bioconductor package, ChIPexoQual, to enable exploration and analysis of ChIP-exo and related experiments. ChIPexoQual evaluates a number of key issues including strand imbalance, library complexity, and signal enrichment of data. Assessment of these features are facilitated through diagnostic plots and summary statistics computed over regions of the genome with varying levels of coverage. We evaluated our QC pipeline with both large collections of public ChIP-exo/nexus data and multiple, new ChIP-exo datasets from Escherichia coli. ChIPexoQual analysis of these datasets resulted in guidelines for using these QC metrics across a wide range of sequencing depths and provided further insights for modelling ChIP-exo data. PMID:28911122

  11. The Slow Controls System of the New Muon g-2 Experiment at Fermilab

    NASA Astrophysics Data System (ADS)

    Eads, Michael; New Muon g-2 Collaboration

    2015-04-01

    The goal of the new muon g-2 experiment (E-989), currently under construction at Fermi National Accelerator Laboratory, is to measure the anomalous gyromagnetic ratio of the muon with unprecedented precision. The uncertainty goal of the experiment, 0.14ppm, represents a four-fold improvement over the current best measurement of this value and has the potential to increase the current three standard deviation disagreement with the predicted standard model value to five standard deviations. Measuring the operating conditions of the experiment will be essential to achieving these uncertainty goals. This talk will describe the design and the current status of E-989's slow controls system. This system, based on the MIDAS Slow Control Bus, will be used to measure and record currents, voltages, temperatures, humidities, pressures, flows, and other data which is collected asynchronously with the injection of the muon beam. The system consists of a variety of sensors and front-end electronics which interface to back-end data acquisition, data storage, and data monitoring systems. Parts of the system are all already operational and the full system will be completed before beam commissioning begins in 2017.

  12. Thermal Control Surfaces Experiment

    NASA Technical Reports Server (NTRS)

    Wilkes, D. R.

    1999-01-01

    This report is the final experiment report for the TCSE and summarizes many years of hardware development and analyses. Also included are analyses presented in a number of TCSE papers that were prepared and given at scientific conferences including three LDEF Post-Retrieval Symposiums.

  13. Additives and method for controlling clathrate hydrates in fluid systems

    DOEpatents

    Sloan, Jr., Earle Dendy; Christiansen, Richard Lee; Lederhos, Joseph P.; Long, Jin Ping; Panchalingam, Vaithilingam; Du, Yahe; Sum, Amadeu Kun Wan

    1997-01-01

    Discussed is a process for preventing clathrate hydrate masses from detrimentally impeding the possible flow of a fluid susceptible to clathrate hydrate formation. The process is particularly useful in the natural gas and petroleum production, transportation and processing industry where gas hydrate formation can cause serious problems. Additives preferably contain one or more five member, six member and/or seven member cyclic chemical groupings. Additives include polymers having lactam rings. Additives can also contain polyelectrolytes that are believed to improve conformance of polymer additives through steric hinderance and/or charge repulsion. Also, polymers having an amide on which a C.sub.1 -C.sub.4 group is attached to the nitrogen and/or the carbonyl carbon of the amide may be used alone, or in combination with ring-containing polymers for enhanced effectiveness. Polymers having at least some repeating units representative of polymerizing at least one of an oxazoline, an N-substituted acrylamide and an N-vinyl alkyl amide are preferred.

  14. Additives and method for controlling clathrate hydrates in fluid systems

    DOEpatents

    Sloan, E.D. Jr.; Christiansen, R.L.; Lederhos, J.P.; Long, J.P.; Panchalingam, V.; Du, Y.; Sum, A.K.W.

    1997-06-17

    Discussed is a process for preventing clathrate hydrate masses from detrimentally impeding the possible flow of a fluid susceptible to clathrate hydrate formation. The process is particularly useful in the natural gas and petroleum production, transportation and processing industry where gas hydrate formation can cause serious problems. Additives preferably contain one or more five member, six member and/or seven member cyclic chemical groupings. Additives include polymers having lactam rings. Additives can also contain polyelectrolytes that are believed to improve conformance of polymer additives through steric hindrance and/or charge repulsion. Also, polymers having an amide on which a C{sub 1}-C{sub 4} group is attached to the nitrogen and/or the carbonyl carbon of the amide may be used alone, or in combination with ring-containing polymers for enhanced effectiveness. Polymers having at least some repeating units representative of polymerizing at least one of an oxazoline, an N-substituted acrylamide and an N-vinyl alkyl amide are preferred.

  15. Conceptualizing threats to tobacco control from international economic agreements: the Brazilian experience.

    PubMed

    Drope, Jeffrey; McGrady, Benn; Bialous, Stella Aguinaga; Lencucha, Raphael; Silva, Vera Luiza da Costa E

    2017-10-19

    Using the results of dozens of interviews with key actors involved in tobacco control policymaking, we examine these actors' perceptions of threats to tobacco control policy efforts from international economic policies on trade and investment. We also evaluate, from a legal perspective, the genuine threats that exist or potential challenges that economic policies may pose to the Brazilian government's public health efforts. We find that most actors did not perceive these economic policies as a major threat to tobacco control. Objectively, we found that some threats do exist. For example, Brazil's attempt to ban most tobacco additives and flavorings continues to met resistance at the World Trade Organization.

  16. Facilitated patient experience feedback can improve nursing care: a pilot study for a phase III cluster randomised controlled trial

    PubMed Central

    2013-01-01

    Background England’s extensive NHS patient survey programme has not fulfilled government promises of widespread improvements in patients’ experiences, and media reports of poor nursing care in NHS hospitals are increasingly common. Impediments to the surveys’ impact on the quality of nursing care may include: the fact that they are not ward-specific, so nurses claim “that doesn’t happen on my ward”; nurses’ scepticism about the relevance of patient feedback to their practice; and lack of prompt communication of results. The surveys’ impact could be increased by: conducting ward-specific surveys; returning results to ward staff more quickly; including patients’ written comments in reports; and offering nurses an opportunity to discuss the feedback. Very few randomised trials have been conducted to test the effectiveness of patient feedback on quality improvement and there have been few, if any, published trials of ward-specific patient surveys. Methods Over two years, postal surveys of recent inpatients were conducted at four-monthly intervals in 18 wards in two NHS Trusts in England. Wards were randomly allocated to Basic Feedback (ward-specific printed patient survey results including patients’ written comments sent to nurses by letter); Feedback Plus (in addition to printed results, ward meetings to discuss results and plan improvements) or Control (no active feedback of survey results). Patient survey responses to questions about nursing care were used to compute wards’ average Nursing Care Scores at each interval. Nurses’ reactions to the patient feedback were recorded. Results Conducting ward-level surveys and delivering ward-specific results was feasible. Ward meetings were effective for engaging nurses and challenging scepticism and patients’ written comments stimulated interest. 4,236 (47%) patients returned questionnaires. Nursing Care Scores improved more for Feedback Plus than Basic Feedback or Control (difference between

  17. Analytical optimal controls for the state constrained addition and removal of cryoprotective agents

    PubMed Central

    Chicone, Carmen C.; Critser, John K.

    2014-01-01

    Cryobiology is a field with enormous scientific, financial and even cultural impact. Successful cryopreservation of cells and tissues depends on the equilibration of these materials with high concentrations of permeating chemicals (CPAs) such as glycerol or 1,2 propylene glycol. Because cells and tissues are exposed to highly anisosmotic conditions, the resulting gradients cause large volume fluctuations that have been shown to damage cells and tissues. On the other hand, there is evidence that toxicity to these high levels of chemicals is time dependent, and therefore it is ideal to minimize exposure time as well. Because solute and solvent flux is governed by a system of ordinary differential equations, CPA addition and removal from cells is an ideal context for the application of optimal control theory. Recently, we presented a mathematical synthesis of the optimal controls for the ODE system commonly used in cryobiology in the absence of state constraints and showed that controls defined by this synthesis were optimal. Here we define the appropriate model, analytically extend the previous theory to one encompassing state constraints, and as an example apply this to the critical and clinically important cell type of human oocytes, where current methodologies are either difficult to implement or have very limited success rates. We show that an enormous increase in equilibration efficiency can be achieved under the new protocols when compared to classic protocols, potentially allowing a greatly increased survival rate for human oocytes, and pointing to a direction for the cryopreservation of many other cell types. PMID:22527943

  18. The effect of additional ankle and midfoot mobilizations on plantar fasciitis: a randomized controlled trial.

    PubMed

    Shashua, Anat; Flechter, Shlomo; Avidan, Liat; Ofir, Dani; Melayev, Alex; Kalichman, Leonid

    2015-04-01

    A single-blind randomized controlled trial. To evaluate the efficacy of ankle and midfoot mobilization on pain and function of patients with plantar fasciitis (PF). Plantar fasciitis is a degenerative process of the plantar fascia, with a lifetime prevalence of approximately 10%. Limited ankle dorsiflexion is a common finding and apparently acts as a contributing factor to the development of PF. Fifty patients with PF, aged 23 to 73 years, were randomly assigned to either the intervention or control group. Both groups received 8 treatments, twice a week, consisting of stretching exercises and ultrasound. In addition, the intervention group received mobilization of the ankle and midfoot joints. Dorsiflexion range of motion was measured at the beginning and at the end of treatment. The results were evaluated by 3 outcomes: the numeric pain-rating scale, Lower Extremity Functional Scale, and algometry. No significant difference was found between groups in any of the outcomes. Both groups showed a significant difference in the numeric pain-rating scale and Lower Extremity Functional Scale. Both groups significantly improved in dorsiflexion range of motion, with no difference between groups. The addition of ankle and foot joint mobilization aimed at improving dorsiflexion range of motion is not more effective than stretching and ultrasound alone in treating PF. The association between limited ankle dorsiflexion and PF is most probably due to soft tissue limitations, not the joints. Trial registered at ClinicalTrials.gov (registration number NCT01439932). Therapy, level 1b.

  19. An overview of zinc addition for BWR dose rate control

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Marble, W.J.

    1995-03-01

    This paper presents an overview of the BWRs employing feedwater zinc addition to reduce primary system dose rates. It identifies which BWRs are using zinc addition and reviews the mechanical injection and passive addition hardware currently being employed. The impact that zinc has on plant chemistry, including the factor of two to four reduction in reactor water Co-60 concentrations, is discussed. Dose rate results, showing the benefits of implementing zinc on either fresh piping surfaces or on pipes with existing films are reviewed. The advantages of using zinc that is isotopically enhanced by the depletion of the Zn-64 precursor tomore » Zn-65 are identified.« less

  20. Additional motional-magnetic-field considerations for electric-dipole-moment experiments

    NASA Astrophysics Data System (ADS)

    Lamoreaux, S. K.

    1996-06-01

    Electric-dipole-moment experiments based on spin-precession measurements of stored atoms or neutrons are generally considered to be immune from the effects of v×E or motional magnetic fields. This is because the average velocity for such systems is zero. We show here that the fluctuating field associated with the random velocity, heretofore not considered, can in fact lead to sizable systematic effects.

  1. Field Testing of a Wet FGD Additive for Enhanced Mercury Control

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gary Blythe; MariJon Owens

    2007-12-31

    This document is the final report for DOE-NETL Cooperative Agreement DE-FC26-04NT42309, 'Field Testing of a Wet FGD Additive'. The objective of the project has been to demonstrate the use of two flue gas desulfurization (FGD) additives, Evonik Degussa Corporation's TMT-15 and Nalco Company's Nalco 8034, to prevent the re-emission of elemental mercury (Hg{sup 0}) in flue gas exiting wet FGD systems on coal-fired boilers. Furthermore, the project was intended to demonstrate whether such additives can be used to precipitate most of the mercury (Hg) removed in the wet FGD system as a fine salt that can be separated from themore » FGD liquor and bulk solid byproducts for separate disposal. The project involved pilot- and full-scale tests of the additives in wet FGD absorbers. The tests were intended to determine required additive dosages to prevent Hg{sup 0} re-emissions and to separate mercury from the normal FGD byproducts for three coal types: Texas lignite/Powder River Basin (PRB) coal blend, high-sulfur Eastern bituminous coal, and low-sulfur Eastern bituminous coal. The project team consists of URS Group, Inc., EPRI, Luminant Power (was TXU Generation Company LP), Southern Company, IPL (an AES company), Evonik Degussa Corporation and the Nalco Company. Luminant Power provided the Texas lignite/PRB co-fired test site for pilot FGD tests and project cost sharing. Southern Company provided the low-sulfur Eastern bituminous coal host site for wet scrubbing tests, the pilot- and full-scale jet bubbling reactor (JBR) FGD systems tested, and project cost sharing. IPL provided the high-sulfur Eastern bituminous coal full-scale FGD test site and cost sharing. Evonik Degussa Corporation provided the TMT-15 additive, and the Nalco Company provided the Nalco 8034 additive. Both companies also supplied technical support to the test program as in-kind cost sharing. The project was conducted in six tasks. Of the six tasks, Task 1 involved project planning and Task 6 involved

  2. Some Insights on Roughness Induced Transition and Control from DNS and Experiments

    NASA Astrophysics Data System (ADS)

    Suryanarayanan, Saikishan; Ibitayo, Ifeoluwa; Goldstein, David; Brown, Garry

    2016-11-01

    We study the receptivity and subsequent evolution of an initially laminar flat boundary layer on a flat plate to single and multiple discrete roughness elements (DRE) using a combination of immersed boundary DNS and water channel flow visualization experiments. We examine the transition caused by a single DRE and demonstrate the possibility of suppressing it by an appropriately designed second DRE in both DNS and experiments. The different phases of transition are identified and the roles of Reynolds numbers based on roughness height and boundary layer thickness are investigated. The underlying mechanisms in the observed transition and its control are understood by examining detailed vorticity flux balances. Connections are also made to recent developments in transient growth and streak instability. A unified picture is sought from a parametric study of different DRE dimensions and orientations. The potential applicability of the observations and understanding derived from this study to controlling transition caused by design and environmental roughness over aircraft wings is discussed. Supported by AFOSR # FA9550-15-1-0345.

  3. Clinical learning experiences of nursing students using an innovative clinical partnership model: A non-randomized controlled trial.

    PubMed

    Chan, Aileen W K; Tang, Fiona W K; Choi, Kai Chow; Liu, Ting; Taylor-Piliae, Ruth E

    2018-06-05

    Clinical practicum is a major learning component for pre-registration nursing students. Various clinical practicum models have been used to facilitate students' clinical learning experiences, employing both university-based and hospital-based clinical teachers. Considering the strengths and limitations of these clinical practicum models, along with nursing workforce shortages, we developed and tested an innovative clinical partnership model (CPM) in Hong Kong. To evaluate an innovative CPM among nursing students actual and preferred clinical learning environment, compared with a conventional facilitation model (CFM). A non-randomized controlled trial examining students' clinical experiences, comparing the CPM (supervised by hospital clinical teacher) with the CFM (supervised by university clinical teacher). One university in Hong Kong. Pre-registration nursing students (N = 331), including bachelor of nursing (n = 246 year three-BN) and masters-entry nursing (n = 85 year one-MNSP). Students were assigned to either the CPM (n = 48 BN plus n = 85 MNSP students) or the CFM (n = 198 BN students) for their clinical practice experiences in an acute medical-surgical ward. Clinical teachers supervised between 6 and 8 students at a time, during these clinical practicums (duration = 4-6 weeks). At the end of the clinical practicum, students were invited to complete the Clinical Learning Environment Inventory (CLEI). Analysis of covariance was used to compare groups; adjusted for age, gender and prior work experience. A total of 259 students (mean age = 22 years, 76% female, 81% prior work experience) completed the CLEI (78% response rate). Students had higher scores on preferred versus actual experiences, in all domains of the CLEI. CPM student experiences indicated a higher preferred task orientation (p = 0.004), while CFM student experiences indicated a higher actual (p < 0.001) and preferred individualization (p = 0

  4. Adolescents' pain experiences following acute blunt traumatic injury: struggle for internal control.

    PubMed

    Crandall, Margie; Kools, Susan; Miaskowski, Christine; Savedra, Marilyn

    2007-10-01

    Although blunt trauma injury is a common cause for adolescent pain, little is known about the experience of pain as perceived by adolescents. Semistructured interviews were conducted with 13 adolescents following blunt trauma injury. Two age-appropriate valid measures (i.e., Adolescent Pediatric Pain Tool and Temporal Dot Matrix) were incorporated into the interviews to elaborate their pain experiences. Grounded theory method was used to analyze data and build substantive theory. Adolescents' behavioral and cognitive actions (i.e., "internal control") to manage and endure pain were influenced by their pain perceptions, physical losses, and clinicians' actions. Nurses, family members, and peers have a crucial role in alleviating adolescents' distress and pain.

  5. Data Assimilation Experiments using Quality Controlled AIRS Version 5 Temperature Soundings

    NASA Technical Reports Server (NTRS)

    SUsskind, Joel

    2008-01-01

    The AIRS Science Team Version 5 retrieval algorithm has been finalized and is now operational at the Goddard DAAC in the processing (and reprocessing) of all AIRS data. The AIRS Science Team Version 5 retrieval algorithm contains two significant improvements over Version 4: 1) Improved physics allows for use of AIRS observations in the entire 4.3 pm C02 absorption band in the retrieval of temperature profile T(p) during both day and night. Tropospheric sounding 15 pm C02 observations are now used primarily in the generation of cloud cleared radiances Ri. This approach allows for the generation of accurate values of Ri and T(p) under most cloud conditions. 2) Another very significant improvement in Version 5 is the ability to generate accurate case-by-case, level-by-level error estimates for the atmospheric temperature profile, as well as for channel-by- channel error estimates for Ri. These error estimates are used for quality control of the retrieved products. We have conducted forecast impact experiments assimilating AIRS temperature profiles with different levels of quality control using the NASA GEOS-5 data assimilation system. Assimilation of quality controlled T(p) resulted in significantly improved forecast skill compared to that obtained from analyses obtained when all data used operationally by NCEP, except for AIRS data, is assimilated. We also conducted an experiment assimilating AIRS radiances uncontaminated by clouds, as done Operationally by ECMWF and NCEP. Forecasts resulting from assimilated AIRS radiances were of poorer quality than those obtained assimilating AIRS temperatures.

  6. Effective communication approaches in tuberculosis control: Health workers' perceptions and experiences.

    PubMed

    Arulchelvan, Sriram; Elangovan, Rengan

    2017-10-01

    Health workers' experiences and understanding of the myths, misconceptions, beliefs about TB, and patients in the community (and effective communication methods) can be useful in designing effective IEC materials and strategies. To study the perceptions and experiences of health workers regarding TB disease, patients, and effective communication strategies in TB control. A survey was conducted among health workers involved in Directly Observed Treatment Short (DOTS) course. Data regarding general health beliefs, prevalent myths and misconceptions about TB in their respective localities, knowledge level among patients, and utilization of various communication strategies were collected. There is a significant increase in knowledge about TB during DOTS among patients, as observed by about half of the health workers. TB patients are aware about how TB spreads to others and their responsibilities. Regular interaction with patients is required for treatment adherence. Two thirds of the health workers believe that media-mix strategy can be very effective in creating awareness among the patients as well as the public. Health workers realized that the video player facility on their mobile phones is useful for showing health-related videos. A combination of mass media and interpersonal communication could be effective for TB control. Face-to-face communication with community members, patient-provider discussions, and information through television could be very effective techniques. Exclusive communication materials should be designed for family members of the patients. Smart phones can be used for effective implementation of TB control programs. Copyright © 2016 Tuberculosis Association of India. Published by Elsevier B.V. All rights reserved.

  7. Computer-controlled attenuator.

    PubMed

    Mitov, D; Grozev, Z

    1991-01-01

    Various possibilities for applying electronic computer-controlled attenuators for the automation of physiological experiments are considered. A detailed description is given of the design of a 4-channel computer-controlled attenuator, in two of the channels of which the output signal can change by a linear step, in the other two channels--by a logarithmic step. This, together with the existence of additional programmable timers, allows to automate a wide range of studies in different spheres of physiology and psychophysics, including vision and hearing.

  8. IN718 Additive Manufacturing Properties and Influences

    NASA Technical Reports Server (NTRS)

    Lambert, Dennis M.

    2015-01-01

    The results of tensile, fracture, and fatigue testing of IN718 coupons produced using the selective laser melting (SLM) additive manufacturing technique are presented. The data have been "sanitized" to remove the numerical values, although certain references to material standards are provided. This document provides some knowledge of the effect of variation of controlled build parameters used in the SLM process, a snapshot of the capabilities of SLM in industry at present, and shares some of the lessons learned along the way. For the build parameter characterization, the parameters were varied over a range that was centered about the machine manufacturer's recommended value, and in each case they were varied individually, although some co-variance of those parameters would be expected. Tensile, fracture, and high-cycle fatigue properties equivalent to wrought IN718 are achievable with SLM-produced IN718. Build and post-build processes need to be determined and then controlled to established limits to accomplish this. It is recommended that a multi-variable evaluation, e.g., design-of experiment (DOE), of the build parameters be performed to better evaluate the co-variance of the parameters.

  9. Valsartan addition to amlodipine is more effective than losartan addition in hypertensive patients inadequately controlled by amlodipine.

    PubMed

    Fogari, Roberto; Mugellini, Amedeo; Preti, Paola; Zoppi, Annalisa; Derosa, Giuseppe

    2010-03-03

    This study evaluated the effects on blood pressure (BP) of valsartan 160 mg or losartan 100 mg addition to amlodipine 5 mg in hypertensive patients. 221 patients with inadequately controlled BP (DBP >or= 90 mmHg) after 4 weeks of treatment with amlodipine 5 mg were randomized to receive losartan/amlodipine combination therapy or valsartan/amlodipine combination therapy for 4 weeks in a cross-over study design. At the end of the wash-out period and of each treatment period, clinic and ambulatory BP measurements were recorded. 166 patients completed the study. Both combination treatments induced a greater ambulatory BP reduction than did monotherapy. However, the further mean reductions in BP versus monotherapy were significantly greater with the valsartan/amlodipine combination (SBP/DBP: -7.9 +/- 3.4/-6.5 +/- 2.6 mmHg for 24-hour, -8.0 +/- 3.4/-6.6 +/- 2.7 mmHg for daytime; -7.7 +/- 3.3/-6.4 +/- 2.7 mmHg for nighttime) than with the losartan/amlodipine combination (SBP/DBP: -5.5 +/- 2.8/-4.2 +/- 2.1 mmHg for 24-hour, -5.7 +/- 2.9/-4.4 +/- 2.2 mmHg for daytime; -4.8 +/- 2.8/-3.7 +/- 2.2 mmHg for nighttime; P < 0.01 vs valsartan/amlodipine). The incidence of adverse events with valsartan/amlodipine (8%) and losartan/amlodipine (9%) was lower than that observed with amlodipine monotherapy (17%; P < 0.05 vs combinations). Valsartan 160 mg plus amlodipine 5 mg produced greater BP reductions than losartan 100 mg plus amlodipine 5 mg.

  10. Experiments on reduction of propeller induced interior noise by active control of cylinder vibration

    NASA Technical Reports Server (NTRS)

    Fuller, C. R.; Jones, J. D.

    1987-01-01

    The feasibility of reducing interior noise caused by advanced turbo propellers by controlling the vibration of aircraft fuselages was investigated by performing experiments in an anechoic chamber with an aircraft model test rig and apparatus. It was found that active vibration control provides reasonable global attenuation of interior noise levels for the cases of resonant (at 576 Hz) and forced (at 708 Hz) system response. The controlling mechanism behind the effect is structural-acoustic coupling between the shell and the contained field, termed interface modal filtering.

  11. Effect of kaolin addition on the performance of controlled low-strength material using industrial waste incineration bottom ash.

    PubMed

    Naganathan, Sivakumar; Razak, Hashim Abdul; Hamid, Siti Nadzriah Abdul

    2010-09-01

    Incineration of industrial waste produces large quantities of bottom ash which are normally sent to secured landfill, but is not a sustainable solution. Use of bottom ash in engineering applications will contribute to sustainability and generate revenue. One way of using the industrial waste incineration bottom ash is in controlled low-strength material (CLSM). Use of bottom ash in CLSM has problems related to bleeding and excessive strength development and so an additive has to be used to control bleeding and strength development. The main objective of this research is to study the effect of kaolin addition on the performance of CLSM made using industrial waste incineration bottom ash. CLSM mixes were made with bottom ash, cement, and refined kaolin. Various tests were performed on the CLSM in fresh and hardened states including compressive strength, water absorption, California bearing ratio (CBR) and the tests for concentration of leachable substances on the bleed and leachate. The compressive strength of CLSM tested ranged from 0.11 to 9.86 MPa. CBR values ranged from 6 to 46, and water absorption values from 12 to 36%. It was shown that the addition of kaolin delayed the initial setting time of CLSM mixtures, reduced bleeding, lowered the compressive strength, and increased the values of water absorption, sorption, and initial surface absorption. The CLSM tested did not have corrosivity. It was shown that the hardened CLSM was non hazardous, and the addition of kaolin increased the concentration of heavy metals and salts in the bleed and leachate.

  12. Long Duration Exposure Facility M0003-5 thermal control coatings on DoD flight experiment

    NASA Technical Reports Server (NTRS)

    Hurley, Charles J.; Lehn, William L.

    1992-01-01

    The M0003-5 thermal control coatings and materials orbited on the LDEF M0003 Space Environment Effects on Spacecraft Materials were a part of a Wright Laboratories Materials Directorate larger experiment. They were selected from new materials which emerged from development programs during the 1978-1982 time frame. Included were materials described in the technical literature which were being considered or had been applied to satellites. Materials that had been exposed on previous satellite materials experiments were also included to provide data correlation with earlier space flight experiments. The objective was to determine the effect of the LDEF environment on the physical and optical properties of thermal control coatings and materials. One hundred and two specimens of various pigmented organic and inorganic coatings, metallized polymer thin films, optical solar reflectors, and mirrors were orbited on LDEF. The materials were exposed in four separate locations on the vehicle. The first set was exposed on the direct leading edge of the satellite. The second set was exposed on the direct trailing edge of the vehicle. The third and fourth sets were exposed in environmental exposure control canisters (EECC) located 30 degrees off normal to the leading and trailing edges. The purpose of the experiment was to understand the changes in the properties of materials before and after exposure to the space environment and to compare the changes with predictions based on laboratory experiments. The basic approach was to measure the optical and physical properties of materials before and after long-term exposure to a low earth orbital environment comprised of UV, VUV, electrons, protons, atomic oxygen, thermal cycling, vacuum, debris, and micrometeoroids. Due to the unanticipated extended orbital flight of LDEF, the thermal control coatings and materials in the direct leading and trailing edge were exposed for a full five years and ten months to the space environment and the

  13. 3D visualization of additive occlusion and tunable full-spectrum fluorescence in calcite

    PubMed Central

    Green, David C.; Ihli, Johannes; Thornton, Paul D.; Holden, Mark A.; Marzec, Bartosz; Kim, Yi-Yeoun; Kulak, Alex N.; Levenstein, Mark A.; Tang, Chiu; Lynch, Christophe; Webb, Stephen E. D.; Tynan, Christopher J.; Meldrum, Fiona C.

    2016-01-01

    From biomineralization to synthesis, organic additives provide an effective means of controlling crystallization processes. There is growing evidence that these additives are often occluded within the crystal lattice. This promises an elegant means of creating nanocomposites and tuning physical properties. Here we use the incorporation of sulfonated fluorescent dyes to gain new understanding of additive occlusion in calcite (CaCO3), and to link morphological changes to occlusion mechanisms. We demonstrate that these additives are incorporated within specific zones, as defined by the growth conditions, and show how occlusion can govern changes in crystal shape. Fluorescence spectroscopy and lifetime imaging microscopy also show that the dyes experience unique local environments within different zones. Our strategy is then extended to simultaneously incorporate mixtures of dyes, whose fluorescence cascade creates calcite nanoparticles that fluoresce white. This offers a simple strategy for generating biocompatible and stable fluorescent nanoparticles whose output can be tuned as required. PMID:27857076

  14. Apollo experience report: Mission planning for Apollo entry

    NASA Technical Reports Server (NTRS)

    Graves, C. A.; Harpold, J. C.

    1972-01-01

    The problems encountered and the experience gained in the entry mission plans, flight software, trajectory-monitoring procedures, and backup trajectory-control techniques of the Apollo Program should provide a foundation upon which future spacecraft programs can be developed. Descriptions of these entry activities are presented. Also, to provide additional background information needed for discussion of the Apollo entry experience, descriptions of the entry targeting for the Apollo 11 mission and the postflight analysis of the Apollo 10 mission are presented.

  15. The Framework Convention on Tobacco Control (FCTC) and the adoption of domestic tobacco control policies: the Ecuadorian experience.

    PubMed

    Albuja, S; Daynard, R A

    2009-02-01

    The present work concerns the adoption of domestic tobacco control legislation in Ecuador after ratification of the World Health Organization (WHO) Framework Convention on Tobacco Control (FCTC). Analysis of legislation, and data collection via interviews with key actors involved in the adoption and implementation of domestic legislation passed purportedly to implement the FCTC and research of the Ecuadorian Congressional Archives. While the FCTC helped raise awareness about tobacco's imminent and future threats to public health, paradoxically, it had the effect of further entrenching tobacco-friendly norms. Philip Morris, with 87% dominance over the Ecuadorian tobacco market, subtly harnessed the FCTC to protect its interests. This outcome was also influenced by poor governmental readiness and intervention, lack of legislative technical capabilities and weak civil society involvement. The Ecuadorian experience suggests that more support should be provided to health ministries, legislatures and local tobacco control organisations to offset the power of the tobacco industry as developing nations get ready to adopt domestic tobacco control legislation.

  16. DASHBOARDS & CONTROL CHARTS EXPERIENCES IN IMPROVING SAFETY AT HANFORD WASHINGTON

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    PREVETTE, S.S.

    2006-02-27

    The aim of this paper is to demonstrate the integration of safety methodology, quality tools, leadership, and teamwork at Hanford and their significant positive impact on safe performance of work. Dashboards, Leading Indicators, Control charts, Pareto Charts, Dr. W. Edward Deming's Red Bead Experiment, and Dr. Deming's System of Profound Knowledge have been the principal tools and theory of an integrated management system. Coupled with involved leadership and teamwork, they have led to significant improvements in worker safety and protection, and environmental restoration at one of the nation's largest nuclear cleanup sites.

  17. Research on equipment of micro-pressure measure and control in loading experiment of plant cell mechanics

    NASA Astrophysics Data System (ADS)

    Zhang, Lian; Yu, Chengbo; Tao, Hongyan; Chen, Xuejun; Zhai, Feng

    2005-12-01

    The equipment is developed to measure and control micro-pressure in loading experiment of plant cell mechanics. The motivation for the development of this equipment was to maintain a stationary micro-pressure on the agar of culturing cells to keep cytoactive in biology experiments. A singlechip controls the stepping motor of this equipment to drive loading equipment in the system, in order to load between 50mN and 250mN under a constant voltage. The accuracy is estimated to be +/-0.4 mN. The structure and control system of this equipment is introduced and described in detail. The experimental results show that the equipment is capable of maintaining a constant, stationary micropressure in cell culturing application and is worth of extending and applying.

  18. Effects of Nitrogen Addition on Litter Decomposition and CO2 Release: Considering Changes in Litter Quantity

    PubMed Central

    Li, Hui-Chao; Hu, Ya-Lin; Mao, Rong; Zhao, Qiong; Zeng, De-Hui

    2015-01-01

    This study aims to evaluate the impacts of changes in litter quantity under simulated N deposition on litter decomposition, CO2 release, and soil C loss potential in a larch plantation in Northeast China. We conducted a laboratory incubation experiment using soil and litter collected from control and N addition (100 kg ha−1 year−1 for 10 years) plots. Different quantities of litter (0, 1, 2 and 4 g) were placed on 150 g soils collected from the same plots and incubated in microcosms for 270 days. We found that increased litter input strongly stimulated litter decomposition rate and CO2 release in both control and N fertilization microcosms, though reduced soil microbial biomass C (MBC) and dissolved inorganic N (DIN) concentration. Carbon input (C loss from litter decomposition) and carbon output (the cumulative C loss due to respiration) elevated with increasing litter input in both control and N fertilization microcosms. However, soil C loss potentials (C output–C input) reduced by 62% in control microcosms and 111% in N fertilization microcosms when litter addition increased from 1 g to 4 g, respectively. Our results indicated that increased litter input had a potential to suppress soil organic C loss especially for N addition plots. PMID:26657180

  19. Differences in cannabis-related experiences between patients with a first episode of psychosis and controls.

    PubMed

    Bianconi, F; Bonomo, M; Marconi, A; Kolliakou, A; Stilo, S A; Iyegbe, C; Gurillo Muñoz, P; Homayoun, S; Mondelli, V; Luzi, S; Dazzan, P; Prata, D; La Cascia, C; O'Connor, J; David, A; Morgan, C; Murray, R M; Lynskey, M; Di Forti, M

    2016-04-01

    Many studies have reported that cannabis use increases the risk of a first episode of psychosis (FEP). However, only a few studies have investigated the nature of cannabis-related experiences in FEP patients, and none has examined whether these experiences are similar in FEP and general populations. The aim of this study was to explore differences in self-reported cannabis experiences between FEP and non-psychotic populations. A total of 252 subjects, who met International Classification of Diseases (ICD)-10 criteria for FEP, and 217 controls who reported cannabis use were selected from the Genetics and Psychosis (GAP) study. The Medical Research Council Social Schedule and the Cannabis Experience Questionnaire were used to collect sociodemographic data and cannabis use information, respectively. Both 'bad' and 'enjoyable' experiences were more commonly reported by FEP subjects than controls. Principal components factor analysis identified four components which explained 62.3% of the variance. Linear regression analysis on the whole sample showed that the type of cannabis used and beliefs about the effect of cannabis on health all contributed to determining the intensity and frequency of experiences. Linear regression analysis on FEP subjects showed that the duration of cannabis use and amount of money spent on cannabis were strongly related to the intensity and frequency of enjoyable experiences in this population. These results suggest a higher sensitivity to cannabis effects among people who have suffered their first psychotic episode; this hypersensitivity results in them reporting both more 'bad' and 'enjoyable' experiences. The greater enjoyment experienced may provide an explanation of why FEP patients are more likely to use cannabis and to continue to use it despite experiencing an exacerbation of their psychotic symptoms.

  20. RNA-seq mixology: designing realistic control experiments to compare protocols and analysis methods

    PubMed Central

    Holik, Aliaksei Z.; Law, Charity W.; Liu, Ruijie; Wang, Zeya; Wang, Wenyi; Ahn, Jaeil; Asselin-Labat, Marie-Liesse; Smyth, Gordon K.

    2017-01-01

    Abstract Carefully designed control experiments provide a gold standard for benchmarking different genomics research tools. A shortcoming of many gene expression control studies is that replication involves profiling the same reference RNA sample multiple times. This leads to low, pure technical noise that is atypical of regular studies. To achieve a more realistic noise structure, we generated a RNA-sequencing mixture experiment using two cell lines of the same cancer type. Variability was added by extracting RNA from independent cell cultures and degrading particular samples. The systematic gene expression changes induced by this design allowed benchmarking of different library preparation kits (standard poly-A versus total RNA with Ribozero depletion) and analysis pipelines. Data generated using the total RNA kit had more signal for introns and various RNA classes (ncRNA, snRNA, snoRNA) and less variability after degradation. For differential expression analysis, voom with quality weights marginally outperformed other popular methods, while for differential splicing, DEXSeq was simultaneously the most sensitive and the most inconsistent method. For sample deconvolution analysis, DeMix outperformed IsoPure convincingly. Our RNA-sequencing data set provides a valuable resource for benchmarking different protocols and data pre-processing workflows. The extra noise mimics routine lab experiments more closely, ensuring any conclusions are widely applicable. PMID:27899618

  1. Data exploration, quality control and statistical analysis of ChIP-exo/nexus experiments.

    PubMed

    Welch, Rene; Chung, Dongjun; Grass, Jeffrey; Landick, Robert; Keles, Sündüz

    2017-09-06

    ChIP-exo/nexus experiments rely on innovative modifications of the commonly used ChIP-seq protocol for high resolution mapping of transcription factor binding sites. Although many aspects of the ChIP-exo data analysis are similar to those of ChIP-seq, these high throughput experiments pose a number of unique quality control and analysis challenges. We develop a novel statistical quality control pipeline and accompanying R/Bioconductor package, ChIPexoQual, to enable exploration and analysis of ChIP-exo and related experiments. ChIPexoQual evaluates a number of key issues including strand imbalance, library complexity, and signal enrichment of data. Assessment of these features are facilitated through diagnostic plots and summary statistics computed over regions of the genome with varying levels of coverage. We evaluated our QC pipeline with both large collections of public ChIP-exo/nexus data and multiple, new ChIP-exo datasets from Escherichia coli. ChIPexoQual analysis of these datasets resulted in guidelines for using these QC metrics across a wide range of sequencing depths and provided further insights for modelling ChIP-exo data. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  2. Fluid loss control additives for oil well cementing compositions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Crema, S.C.; Kucera, C.H.

    1992-03-03

    This patent describes a cementing composition useful in cementing oil, gas and water wells. It comprises hydraulic cement; and a fluid loss additive in an amount effective to reduce fluid loss, the fluid loss additive comprised of a copolymer of acrylamide monomer and vinyl formamide monomer and derivatives thereof in a weight percent ratio of from about 95:5 to 5:95, the copolymer having a molecular weight range of from about 10,000 to 3,000,000, the acrylamide monomer being selected from the group consisting of acrylamide, methacrylamide, N,N-dimethyl(meth)acrylamide, dialkylaminoalkyl(meth) acrylamide and mixtures thereof, the vinyl formamide monomer being selected from the groupmore » consisting of vinyl formamide, its hydrolysis products and derivatives thereof.« less

  3. Mental Workload and Performance Experiment (MWPE) Team in the Spacelab Payload Operations Control

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The primary payload for Space Shuttle Mission STS-42, launched January 22, 1992, was the International Microgravity Laboratory-1 (IML-1), a pressurized manned Spacelab module. The goal of IML-1 was to explore in depth the complex effects of weightlessness of living organisms and materials processing. Around-the-clock research was performed on the human nervous system's adaptation to low gravity and effects of microgravity on other life forms such as shrimp eggs, lentil seedlings, fruit fly eggs, and bacteria. Materials processing experiments were also conducted, including crystal growth from a variety of substances such as enzymes, mercury iodide, and a virus. The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Featured is the Mental Workload and Performance Experiment (MWPE) team in the SL POCC) during STS-42, IML-1 mission.

  4. Mental Workload and Performance Experiment (MWPE) Team in the Spacelab Payload Operations Control

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The primary payload for Space Shuttle Mission STS-42, launched January 22, 1992, was the International Microgravity Laboratory-1 (IML-1), a pressurized manned Spacelab module. The goal of IML-1 was to explore in depth the complex effects of weightlessness of living organisms and materials processing. Around-the-clock research was performed on the human nervous system's adaptation to low gravity and effects of microgravity on other life forms such as shrimp eggs, lentil seedlings, fruit fly eggs, and bacteria. Materials processing experiments were also conducted, including crystal growth from a variety of substances such as enzymes, mercury iodide, and a virus. The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Featured activities are of the Mental Workload and Performance Experiment (MWPE) team in the SL POCC during the IML-1 mission.

  5. Placebo versus low-dose ketamine infusion in addition to remifentanil target-controlled infusion for conscious sedation during oocyte retrieval: A prospective, double-blinded, randomised controlled trial.

    PubMed

    Morue, Hélène I; Raj-Lawrence, Shalini; Saxena, Sarah; Delbaere, Anne; Engelman, Edgard; Barvais, Luc A

    2018-04-30

    Currently, there is no gold standard for monitored anaesthesia care during oocyte retrieval. In our institution, the standard is a conscious sedation technique using a target-controlled infusion (TCI) of remifentanil, titrated to maintain a visual analogue pain score less than 30 mm. This protocol is well accepted by patients but is associated with frequent episodes of respiratory depression. The main objective of this study was to evaluate whether the addition of a continuous intravenous infusion of ketamine could reduce these episodes. Controlled, randomised, prospective, double-blinded study. The current study was conducted in a tertiary-level hospital in Brussels (Belgium) from December 2013 to June 2014. Of the 132 women undergoing oocyte retrieval included, 121 completed the study. After randomisation, patients received either a ketamine infusion (40 μg kg min over 5 min followed by 2.5 μg kg min) or a 0.9% saline infusion in addition to the variable remifentanil TCI. The primary outcome was the number of respiratory depression episodes. Effect site target remifentanil concentrations, side effects, pain score, patient satisfaction and incidence of pregnancy were also recorded. No significant difference in the incidence of respiratory events was noted (pulse oximetry oxygen saturation < 95% was 49% in the ketamine group and 63% in the control group; P = 0.121). No patient required ventilatory support. In the ketamine group, visual analogue pain score and remifentanil concentrations were significantly reduced, but the latter remained above 2 ng ml. Postoperative nausea was less frequent in the ketamine group, 4 versus 15% (P = 0.038). The addition of ketamine did not influence length of stay nor patient satisfaction. The addition of low plasma levels of ketamine to a TCI remifentanil conscious sedation technique did not decrease the incidence nor the severity of respiratory depression. Continuous monitoring of capnography and

  6. Object library for a new generation of experiment-controlling applications under the UNIX operating system.

    PubMed

    Gaponov, Y A; Ito, K; Amemiya, Y

    1998-05-01

    The Interface Object Library based on the Motif extension of the X Windows system and on the ESONE SVIC-VCC Library is presented. Some features of the applications for controlling a synchrotron radiation experiment are discussed. The Interface Object Library is written in the object-oriented C++ language. The library class-hierarchy structure is presented and discussed. Several interfaces were realized in the Interface Object Library: the Windows interface, the CAMAC interface and the interface for supporting the experiment. The behaviour of the objects describing the CAMAC crate and CAMAC block is discussed. The application of these protocols for controlling the fast one-coordinate position-sensitive X-ray detector OD3 is presented.

  7. Electrolysis Performance Improvement Concept Study (EPICS) flight experiment phase C/D

    NASA Technical Reports Server (NTRS)

    Schubert, F. H.; Lee, M. G.

    1995-01-01

    The overall purpose of the Electrolysis Performance Improvement Concept Study flight experiment is to demonstrate and validate in a microgravity environment the Static Feed Electrolyzer concept as well as investigate the effect of microgravity on water electrolysis performance. The scope of the experiment includes variations in microstructural characteristics of electrodes and current densities in a static feed electrolysis cell configuration. The results of the flight experiment will be used to improve efficiency of the static feed electrolysis process and other electrochemical regenerative life support processes by reducing power and expanding the operational range. Specific technologies that will benefit include water electrolysis for propulsion, energy storage, life support, extravehicular activity, in-space manufacturing and in-space science in addition to other electrochemical regenerative life support technologies such as electrochemical carbon dioxide and oxygen separation, electrochemical oxygen compression and water vapor electrolysis. The Electrolysis Performance Improvement Concept Study flight experiment design incorporates two primary hardware assemblies: the Mechanical/Electrochemical Assembly and the Control/Monitor Instrumentation. The Mechanical/Electrochemical Assembly contains three separate integrated electrolysis cells along with supporting pressure and temperature control components. The Control/Monitor Instrumentation controls the operation of the experiment via the Mechanical/Electrochemical Assembly components and provides for monitoring and control of critical parameters and storage of experimental data.

  8. Intraguild relationships between sympatric predators exposed to lethal control: predator manipulation experiments

    PubMed Central

    2013-01-01

    Introduction Terrestrial top-predators are expected to regulate and stabilise food webs through their consumptive and non-consumptive effects on sympatric mesopredators and prey. The lethal control of top-predators has therefore been predicted to inhibit top-predator function, generate the release of mesopredators and indirectly harm native fauna through trophic cascade effects. Understanding the outcomes of lethal control on interactions within terrestrial predator guilds is important for zoologists, conservation biologists and wildlife managers. However, few studies have the capacity to test these predictions experimentally, and no such studies have previously been conducted on the eclectic suite of native and exotic, mammalian and reptilian taxa we simultaneously assess. We conducted a series of landscape-scale, multi-year, manipulative experiments at nine sites spanning five ecosystem types across the Australian continental rangelands to investigate the responses of mesopredators (red foxes, feral cats and goannas) to contemporary poison-baiting programs intended to control top-predators (dingoes) for livestock protection. Result Short-term behavioural releases of mesopredators were not apparent, and in almost all cases, the three mesopredators we assessed were in similar or greater abundance in unbaited areas relative to baited areas, with mesopredator abundance trends typically either uncorrelated or positively correlated with top-predator abundance trends over time. The exotic mammals and native reptile we assessed responded similarly (poorly) to top-predator population manipulation. This is because poison baits were taken by multiple target and non-target predators and top-predator populations quickly recovered to pre-control levels, thus reducing the overall impact of baiting on top-predators and averting a trophic cascade. Conclusions These results are in accord with other predator manipulation experiments conducted worldwide, and suggest that Australian

  9. Intraguild relationships between sympatric predators exposed to lethal control: predator manipulation experiments.

    PubMed

    Allen, Benjamin L; Allen, Lee R; Engeman, Richard M; Leung, Luke K-P

    2013-07-10

    Terrestrial top-predators are expected to regulate and stabilise food webs through their consumptive and non-consumptive effects on sympatric mesopredators and prey. The lethal control of top-predators has therefore been predicted to inhibit top-predator function, generate the release of mesopredators and indirectly harm native fauna through trophic cascade effects. Understanding the outcomes of lethal control on interactions within terrestrial predator guilds is important for zoologists, conservation biologists and wildlife managers. However, few studies have the capacity to test these predictions experimentally, and no such studies have previously been conducted on the eclectic suite of native and exotic, mammalian and reptilian taxa we simultaneously assess. We conducted a series of landscape-scale, multi-year, manipulative experiments at nine sites spanning five ecosystem types across the Australian continental rangelands to investigate the responses of mesopredators (red foxes, feral cats and goannas) to contemporary poison-baiting programs intended to control top-predators (dingoes) for livestock protection. Short-term behavioural releases of mesopredators were not apparent, and in almost all cases, the three mesopredators we assessed were in similar or greater abundance in unbaited areas relative to baited areas, with mesopredator abundance trends typically either uncorrelated or positively correlated with top-predator abundance trends over time. The exotic mammals and native reptile we assessed responded similarly (poorly) to top-predator population manipulation. This is because poison baits were taken by multiple target and non-target predators and top-predator populations quickly recovered to pre-control levels, thus reducing the overall impact of baiting on top-predators and averting a trophic cascade. These results are in accord with other predator manipulation experiments conducted worldwide, and suggest that Australian populations of native prey fauna

  10. Website Use and Effects of Online Information About Tobacco Additives Among the Dutch General Population: A Randomized Controlled Trial

    PubMed Central

    Crutzen, Rik; Kienhuis, Anne S; Talhout, Reinskje; de Vries, Hein

    2017-01-01

    Background As a legal obligation, the Dutch government publishes online information about tobacco additives to make sure that it is publicly available. Little is known about the influence this website (”tabakinfo”) has on visitors and how the website is evaluated by them. Objective This study assesses how visitors use the website and its effect on their knowledge, risk perception, attitude, and smoking behavior. The study will also assess how the website is evaluated by visitors using a sample of the Dutch general population, including smokers and nonsmokers. Methods A randomized controlled trial was conducted, recruiting participants from an online panel. At baseline, participants (N=672) were asked to fill out an online questionnaire about tobacco additives. Next, participants were randomly allocated to either one of two experimental groups and invited to visit the website providing information about tobacco additives (either with or without a database containing product-specific information) or to a control group that had no access to the website. After 3 months, follow-up measurements took place. Results At follow-up (n=492), no statistically significant differences were found for knowledge, risk perception, attitude, or smoking behavior between the intervention and control groups. Website visits were positively related to younger participants (B=–0.07, 95% CI –0.12 to –0.01; t11=–2.43, P=.02) and having a low risk perception toward tobacco additives (B=–0.32, 95% CI –0.63 to –0.02; t11=–2.07, P=.04). In comparison, having a lower education (B=–0.67, 95% CI –1.14 to –0.17; t11=–2.65, P=.01) was a significant predictor for making less use of the website. Furthermore, the website was evaluated less positively by smokers compared to nonsmokers (t324=–3.55, P<.001), and males compared to females (t324=–2.21, P=.02). Conclusions The website did not change perceptions of tobacco additives or smoking behavior. Further research is

  11. Website Use and Effects of Online Information About Tobacco Additives Among the Dutch General Population: A Randomized Controlled Trial.

    PubMed

    Reinwand, Dominique A; Crutzen, Rik; Kienhuis, Anne S; Talhout, Reinskje; de Vries, Hein

    2017-03-14

    As a legal obligation, the Dutch government publishes online information about tobacco additives to make sure that it is publicly available. Little is known about the influence this website ("tabakinfo") has on visitors and how the website is evaluated by them. This study assesses how visitors use the website and its effect on their knowledge, risk perception, attitude, and smoking behavior. The study will also assess how the website is evaluated by visitors using a sample of the Dutch general population, including smokers and nonsmokers. A randomized controlled trial was conducted, recruiting participants from an online panel. At baseline, participants (N=672) were asked to fill out an online questionnaire about tobacco additives. Next, participants were randomly allocated to either one of two experimental groups and invited to visit the website providing information about tobacco additives (either with or without a database containing product-specific information) or to a control group that had no access to the website. After 3 months, follow-up measurements took place. At follow-up (n=492), no statistically significant differences were found for knowledge, risk perception, attitude, or smoking behavior between the intervention and control groups. Website visits were positively related to younger participants (B=-0.07, 95% CI -0.12 to -0.01; t 11 =-2.43, P=.02) and having a low risk perception toward tobacco additives (B=-0.32, 95% CI -0.63 to -0.02; t 11 =-2.07, P=.04). In comparison, having a lower education (B=-0.67, 95% CI -1.14 to -0.17; t 11 =-2.65, P=.01) was a significant predictor for making less use of the website. Furthermore, the website was evaluated less positively by smokers compared to nonsmokers (t 324 =-3.55, P<.001), and males compared to females (t 324 =-2.21, P=.02). The website did not change perceptions of tobacco additives or smoking behavior. Further research is necessary to find out how online information can be used to effectively

  12. Nitrogen and phosphorus addition impact soil N2O emission in a secondary tropical forest of South China

    PubMed Central

    Wang, Faming; Li, Jian; Wang, Xiaoli; Zhang, Wei; Zou, Bi; Neher, Deborah A.; Li, Zhian

    2014-01-01

    Nutrient availability greatly regulates ecosystem processes and functions of tropical forests. However, few studies have explored impacts of N addition (aN), P addition (aP) and N×P interaction on tropical forests N2O fluxes. We established an N and P addition experiment in a tropical forest to test whether: (1) N addition would increase N2O emission and nitrification, and (2) P addition would increase N2O emission and N transformations. Nitrogen and P addition had no effect on N mineralization and nitrification. Soil microbial biomass was increased following P addition in wet seasons. aN increased 39% N2O emission as compared to control (43.3 μgN2O-N m−2h−1). aP did not increase N2O emission. Overall, N2O emission was 60% greater for aNP relative to the control, but significant difference was observed only in wet seasons, when N2O emission was 78% greater for aNP relative to the control. Our results suggested that increasing N deposition will enhance soil N2O emission, and there would be N×P interaction on N2O emission in wet seasons. Given elevated N deposition in future, P addition in this tropical soil will stimulate soil microbial activities in wet seasons, which will further enhance soil N2O emission. PMID:25001013

  13. Report on July 2015 Additional Protocol Coordinators Best Practices Workshop

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gitau, Ernest T.N.; Burbank, Roberta L.; Finch, Valerie A.

    After 10 years of implementation experience, the Office of Nonproliferation and Arms Control (NPAC) within the Department of Energy/National Nuclear Security Administration (DOE/NNSA) conducted the Additional Protocol (AP) Coordinators Best Practices Workshop at Oak Ridge National Laboratory from July 29-30, 2015. The goal of this workshop was to identify implementation best practices, lessons learned, and compliance challenges from the various Additional Protocol Coordinators (APCs) at each laboratory in the DOE/NNSA complex and associated sites. The workshop provided the opportunity for participants to share their insights and establish networks that APCs can utilize to continue to discuss challenges (new and old),more » identify best practices, and enhance communication and coordination for reporting multi-lab research projects during review activities. Workshop participants included DOE/NNSA HQ, laboratory and site APCs, seasoned experts, members of the original implementation outreach team, and Field Element and site security representatives.« less

  14. Effect of sodium azide addition and aging storage on casein micelle size

    NASA Astrophysics Data System (ADS)

    Sinaga, H.; Deeth, H.; Bhandari, B.

    2018-02-01

    Casein micelles affected most of milk properties, therefore the use sodium azide as milk preservation is not expected to alter milk properties during storage, including the casein micelle size. The aim of this study was to analyse casein micelle size after the addition of sodium azide during storage. The experiment was performed as a complete block randomised design with three replications. The addition of 0.02-0.10% Na-azide do not lead to any noticeable differences in average casein size at the same day and show similar trend after 14 day-storage. At concentration of 0.02% sodium azide (Na-azide), the size of pasteurised milk did not change up to 12 days, while the size of raw skim milk slightly increased by ageing time at day 5. The treated concentration did not affect the size distribution, except for milk with 0.02% Na-azide which had narrower distribution compared to other treated and control milk. The finding from this study suggests that the role of Na-azide in this experiments during storage at 4°C is only for preventing the microbial growth.

  15. Interactive effects of nutrient additions and predation on infaunal communities

    USGS Publications Warehouse

    Posey, M.H.; Alphin, T.D.; Cahoon, L.; Lindquist, D.; Becker, M.E.

    1999-01-01

    Nutrient additions represent an important anthropogenic stress on coastal ecosystems. At moderate levels, increased nutrients may lead to increased primary production and, possibly, to increased biomass of consumers although complex trophic interactions may modify or mask these effects. We examined the influence of nutrient additions and interactive effects of trophic interactions (predation) on benthic infaunal composition and abundances through small-scale field experiments in 2 estuaries that differed in ambient nutrient conditions. A blocked experimental design was used that allowed an assessment of direct nutrient effects in the presence and absence of predation by epibenthic predators as well as an assessment of the independent effects of predation. Benthic microalgal production increased with experimental nutrient additions and was greater when infaunal abundances were lower, but there were no significant interactions between these factors. Increased abundances of one infaunal taxa, Laeonereis culveri, as well as the grazer feeding guild were observed with nutrient additions and a number of taxa exhibited higher abundances with predator exclusion. In contrast to results from freshwater systems there were no significant interactive effects between nutrient additions and predator exclusion as was predicted. The infaunal responses observed here emphasize the importance of both bottom-up (nutrient addition and primary producer driven) and top-down (predation) controls in structuring benthic communities. These processes may work at different spatial and temporal scales, and affect different taxa, making observation of potential interactive effects difficult.

  16. Viscosity Control Experiment Feasibility Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Morris, Heidi E.; Bradley, Paul Andrew

    Turbulent mix has been invoked to explain many results in Inertial Confinement Fusion (ICF) and High Energy Density (HED) physics, such as reduced yield in capsule implosions. Many ICF capsule implosions exhibit interfacial instabilities seeded by the drive shock, but it is not clear that fully developed turbulence results from this. Many simulations use turbulent mix models to help match simulation results to data, but this is not appropriate if turbulence is not present. It would be useful to have an experiment where turbulent mixing could be turned on or off by design. The use of high-Z dopants to modifymore » viscosity and the resulting influence on turbulence is considered here. A complicating factor is that the plasma in some implosions can become strongly coupled, which makes the Spitzer expression for viscosity invalid. We first consider equations that cover a broad parameter space in temperature and density to address regimes for various experimental applications. Next, a previous shock-tube and other ICF experiments that investigate viscosity or use doping to examine the effects on yield are reviewed. How viscosity and dopants play a role in capsule yield depends on the region and process under consideration. Experiments and simulations have been performed to study the effects of viscosity on both the hot spot and the fuel/ablator mix. Increases in yield have been seen for some designs, but not all. We then discuss the effect of adding krypton dopant to the gas region of a typical OMEGA and a 2-shock NIF implosion to determine approximately the effect of adding dopant on the computed Reynolds number. Recommendations for a path forward for possible experiments using high-Z dopants to affect viscosity and turbulence are made.« less

  17. Additives in plastics.

    PubMed Central

    Deanin, R D

    1975-01-01

    The polymers used in plastics are generally harmless. However, they are rarely used in pure form. In almost all commercial plastics, they are "compounded" with monomeric ingredients to improve their processing and end-use performance. In order of total volume used, these monomeric additives may be classified as follows: reinforcing fibers, fillers, and coupling agents; plasticizers; colorants; stabilizers (halogen stabilizers, antioxidants, ultraviolet absorbers, and biological preservatives); processing aids (lubricants, others, and flow controls); flame retardants, peroxides; and antistats. Some information is already available, and much more is needed, on potential toxicity and safe handling of these additives during processing and manufacture of plastics products. PMID:1175566

  18. Design of a CO2 laser power control system for a Spacelab microgravity experiment

    NASA Technical Reports Server (NTRS)

    Wenzler, Carl J.; Eichenberg, Dennis J.

    1990-01-01

    The surface tension driven convection experiment (STDCE) is a Space Transportation System flight experiment manifested to fly aboard the USML-1 Spacelab mission. A CO2 laser is used to heat a spot on the surface of silicone oil contained inside a test chamber. Several CO2 laser control systems were evaluated and the selected system will be interfaced with the balance of the experimental hardware to constitute a working engineering model. Descriptions and a discussion of these various design approaches are presented.

  19. Further investigations of experiment A0034 atomic oxygen stimulated outgassing

    NASA Technical Reports Server (NTRS)

    Linton, Roger C.; Finckenor, Miria M.; Kamenetzky, Rachel R.

    1995-01-01

    Thermal control coatings within the recessed compartments of LDEF Experiment A0034 experienced the maximum leading edge fluence of atomic oxygen with considerably less solar UV radiation exposure than top-surface mounted materials of other LDEF experiments on either the leading or the trailing edge. This combination of exposure within A0034 resulted in generally lower levels of darkening attributable to solar UV radiation than for similar materials on other LDEF experiments exposed to greater cumulative solar UV radiation levels. Changes in solar absorptance and infrared thermal emittance of the exposed coatings are thus unique to this exposure. Analytical results for other applications have been found for environmentally induced changes in fluorescence, surface morphology, light scattering, and the effects of coating outgassing products on adjacent mirrors and windows of the A0034 experiment. Some atmospheric bleaching of the thermal control coatings, in addition to that presumably experience during reentry and recovery operations, has been found since initial post-flight observations and measurements.

  20. Kinetics of the addition of olefins to Si-centered radicals: the critical role of dispersion interactions revealed by theory and experiment.

    PubMed

    Johnson, Erin R; Clarkin, Owen J; Dale, Stephen G; DiLabio, Gino A

    2015-06-04

    Solution-phase rate constants for the addition of selected olefins to the triethylsilyl and tris(trimethylsilyl)silyl radicals are measured using laser-flash photolysis and competition kinetics. The results are compared with predictions from density functional theory (DFT) calculations, both with and without dispersion corrections obtained from the exchange-hole dipole moment (XDM) model. Without a dispersion correction, the rate constants are consistently underestimated; the errors increase with system size, up to 10(6) s(-1) for the largest system considered. Dispersion interactions preferentially stabilize the transition states relative to the separated reactants and bring the DFT-calculated rate constants into excellent agreement with experiment. Thus, dispersion interactions are found to play a key role in determining the kinetics for addition reactions, particularly those involving sterically bulky functional groups.

  1. Metal vapor micro-jet controls material redistribution in laser powder bed fusion additive manufacturing.

    PubMed

    Ly, Sonny; Rubenchik, Alexander M; Khairallah, Saad A; Guss, Gabe; Matthews, Manyalibo J

    2017-06-22

    The results of detailed experiments and finite element modeling of metal micro-droplet motion associated with metal additive manufacturing (AM) processes are presented. Ultra high speed imaging of melt pool dynamics reveals that the dominant mechanism leading to micro-droplet ejection in a laser powder bed fusion AM is not from laser induced recoil pressure as is widely believed and found in laser welding processes, but rather from vapor driven entrainment of micro-particles by an ambient gas flow. The physics of droplet ejection under strong evaporative flow is described using simulations of the laser powder bed interactions to elucidate the experimental results. Hydrodynamic drag analysis is used to augment the single phase flow model and explain the entrainment phenomenon for 316 L stainless steel and Ti-6Al-4V powder layers. The relevance of vapor driven entrainment of metal micro-particles to similar fluid dynamic studies in other fields of science will be discussed.

  2. Metal vapor micro-jet controls material redistribution in laser powder bed fusion additive manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ly, Sonny; Rubenchik, Alexander M.; Khairallah, Saad A.

    The results of detailed experiments and finite element modeling of metal micro-droplet motion associated with metal additive manufacturing (AM) processes are presented. Ultra high speed imaging of melt pool dynamics reveals that the dominant mechanism leading to micro-droplet ejection in a laser powder bed fusion AM is not from laser induced recoil pressure as is widely believed and found in laser welding processes, but rather from vapor driven entrainment of micro-particles by an ambient gas flow. The physics of droplet ejection under strong evaporative flow is described using simulations of the laser powder bed interactions to elucidate the experimental results.more » Hydrodynamic drag analysis is used to augment the single phase flow model and explain the entrainment phenomenon for 316 L stainless steel and Ti-6Al-4V powder layers. The relevance of vapor driven entrainment of metal micro-particles to similar fluid dynamic studies in other fields of science will be discussed.« less

  3. Metal vapor micro-jet controls material redistribution in laser powder bed fusion additive manufacturing

    DOE PAGES

    Ly, Sonny; Rubenchik, Alexander M.; Khairallah, Saad A.; ...

    2017-06-22

    The results of detailed experiments and finite element modeling of metal micro-droplet motion associated with metal additive manufacturing (AM) processes are presented. Ultra high speed imaging of melt pool dynamics reveals that the dominant mechanism leading to micro-droplet ejection in a laser powder bed fusion AM is not from laser induced recoil pressure as is widely believed and found in laser welding processes, but rather from vapor driven entrainment of micro-particles by an ambient gas flow. The physics of droplet ejection under strong evaporative flow is described using simulations of the laser powder bed interactions to elucidate the experimental results.more » Hydrodynamic drag analysis is used to augment the single phase flow model and explain the entrainment phenomenon for 316 L stainless steel and Ti-6Al-4V powder layers. The relevance of vapor driven entrainment of metal micro-particles to similar fluid dynamic studies in other fields of science will be discussed.« less

  4. [Working memory and executive control: inhibitory processes in updating and random generation tasks].

    PubMed

    Macizo, Pedro; Bajo, Teresa; Soriano, Maria Felipa

    2006-02-01

    Working Memory (WM) span predicts subjects' performance in control executive tasks and, in addition, it has been related to the capacity to inhibit irrelevant information. In this paper we investigate the role of WM span in two executive tasks focusing our attention on inhibitory components of both tasks. High and low span participants recalled targets words rejecting irrelevant items at the same time (Experiment 1) and they generated random numbers (Experiment 2). Results showed a clear relation between WM span and performance in both tasks. In addition, analyses of intrusion errors (Experiment 1) and stereotyped responses (Experiment 2) indicated that high span individuals were able to efficiently use the inhibitory component implied in both tasks. The pattern of data provides support to the relation between WM span and control executive tasks through an inhibitory mechanism.

  5. Experimente ueber den Einflusse von Metaboliten und Antimetaboliten am Modell von Trichomonas Vaginalis. IX. Mitteilung: Experimente mit Enzymen (Experiments on the Influence of Metabolites and Antimetabolites on the Model of Trichomonas Vaginalis. IX. Communication: Experiments on Enzymes),

    DTIC Science & Technology

    some enzymes to trichomonas. The following enzymes were used for experiment: pepsin, trypsin, distaste, urease and lysozyme. Tests were performed...obtained in the experiments with urease . Trichomonas growth under addition of lysozyme was within the range of the control cultures. (Modified author abstract)

  6. Experience with pornography: Rapists, pedophiles, homosexuals, transsexuals, and controls.

    PubMed

    Goldstein, M; Kant, H; Judd, L; Rice, C; Green, R

    1971-03-01

    An interview designed to assess a respondent's experience with erotic material in photographs, films, and books, during adolescence and adulthood, was administered to convicted male rapists, pedophiles, homosexuals, transsexuals, heavy pornography users, and two nondeviant contrast groups. One nondeviant group was composed of whites matched for the sex offender group; the other was composed of ghetto and middle-class blacks. Adolescent exposure to erotica was significantly less for all deviant and offender groups compared to the nondeviants. During adulthood, the sex offenders and transsexuals continued to report less exposure to erotic stimuli than controls. The homosexuals and users, however, both report greater exposure during adulthood. As adolescents, the control group, rapists, and heavy users were excited to masturbate by the erotic materials more than the other groups. As adults, the controls and rapists showed a sharp decrease in being excited to masturbate to erotica while the users' rate remained high and the homosexuals' rate rose. Less than a quarter of the respondents in any group imitated sexual behavior seen in the erotic material immediately or shortly after its viewing. The hypothesis that extent of exposure during adolescence to erotica is positively associated with the later emergence of sexual pathology is not borne out by this study. The nondeviant, non-sex-offender groups sampled had had significantly greater exposure to erotic materials during adolescence than the deviants, convicted sex offenders, or heavy adult users of pornography.

  7. Electron-ion hybrid instability experiment upgrades to the Auburn Linear Experiment for Instability Studies.

    PubMed

    DuBois, A M; Arnold, I; Thomas, E; Tejero, E; Amatucci, W E

    2013-04-01

    The Auburn Linear EXperiment for Instability Studies (ALEXIS) is a laboratory plasma physics experiment used to study spatially inhomogeneous flows in a magnetized cylindrical plasma column that are driven by crossed electric (E) and magnetic (B) fields. ALEXIS was recently upgraded to include a small, secondary plasma source for a new dual source, interpenetrating plasma experiment. Using two plasma sources allows for highly localized electric fields to be made at the boundary of the two plasmas, inducing strong E × B velocity shear in the plasma, which can give rise to a regime of instabilities that have not previously been studied in ALEXIS. The dual plasma configuration makes it possible to have independent control over the velocity shear and the density gradient. This paper discusses the recent addition of the secondary plasma source to ALEXIS, as well as the plasma diagnostics used to measure electric fields and electron densities.

  8. Manipulating crystallization with molecular additives.

    PubMed

    Shtukenberg, Alexander G; Lee, Stephanie S; Kahr, Bart; Ward, Michael D

    2014-01-01

    Given the importance of organic crystals in a wide range of industrial applications, the chemistry, biology, materials science, and chemical engineering communities have focused considerable attention on developing methods to control crystal structure, size, shape, and orientation. Tailored additives have been used to control crystallization to great effect, presumably by selectively binding to particular crystallographic surfaces and sites. However, substantial knowledge gaps still exist in the fundamental mechanisms that govern the formation and growth of organic crystals in both the absence and presence of additives. In this review, we highlight research discoveries that reveal the role of additives, either introduced by design or present adventitiously, on various stages of formation and growth of organic crystals, including nucleation, dislocation spiral growth mechanisms, growth inhibition, and nonclassical crystal morphologies. The insights from these investigations and others of their kind are likely to guide the development of innovative methods to manipulate crystallization for a wide range of materials and applications.

  9. Whisker/Cone growth on the thermal control surfaces experiment no. S0069

    NASA Technical Reports Server (NTRS)

    Zwiener, James M.; Coston, James E., Jr.; Miller, Edgar R.; Mell, Richard J.; Wilkes, Donald R.

    1995-01-01

    An unusual surface 'growth' was found during scanning electron microscope (SEM) investigations of the Thermal Control Surface Experiment (TCSE) S0069 front thermal cover. This 'growth' is similar to the cone type whisker growth phenomena as studied by G. K. Wehner beginning in the 1960's. Extensive analysis has identified the most probable composition of the whiskers to be a silicate type glass. Sources of the growth material are outgassing products from the experiment and orbital atomic oxygen, which occurs naturally at the orbital altitudes of the LDEF mission in the form of neutral atomic oxygen. The highly ordered symmetry and directionality of the whiskers are attributed to the long term (5.8 year) stable flight orientation of the LDEF.

  10. Children with Heavy Prenatal Alcohol Exposure Experience Reduced Control of Isotonic Force

    PubMed Central

    Nguyen, Tanya T.; Levy, Susan S.; Riley, Edward P.; Thomas, Jennifer D.; Simmons, Roger W.

    2013-01-01

    Background Heavy prenatal alcohol exposure can result in diverse and extensive damage to the central nervous system, including the cerebellum, basal ganglia, and cerebral cortex. Given that these brain regions are involved in the generation and maintenance of motor force, we predicted that prenatal alcohol exposure would adversely affect this parameter of motor control. We previously reported that children with gestational alcohol exposure experience significant deficits in regulating isometric (i.e., constant) force. The purpose of the present study was to determine if these children exhibit similar deficits when producing isotonic (i.e., graded) force. Methods Children with heavy prenatal alcohol exposure and typically developing children completed a series of isotonic force contractions by exerting force on a load cell to match a criterion target force displayed on a computer monitor. Two levels of target force (5% or 20% of maximum voluntary force) were investigated in combination with varying levels of visual feedback. Results Compared to controls, children with heavy prenatal alcohol exposure generated isotonic force signals that were less accurate, more variable, and less complex in the time domain compared to control children. Specifically, interactions were found between group and visual feedback for response accuracy and signal complexity, suggesting that these children have greater difficulty altering their motor output when visual feedback is low. Conclusions These data suggest that prenatal alcohol exposure produces deficits in regulating isotonic force, which presumably result from alcohol-related damage to developing brain regions involved in motor control. These children will most likely experience difficulty performing basic motor skills and daily functional skills that require coordination of finely graded force. Therapeutic strategies designed to increase feedback and, consequently, facilitate visual-motor integration could improve isotonic force

  11. Cigarette taxation in China: lessons from international experiences

    PubMed Central

    Hu, T.

    1997-01-01

    This paper draws upon the experiences of foreign countries in implementing tobacco taxation to provide lessons the Chinese government can use when considering the feasibility of raising additional taxes on cigarettes. Based on current international data and Chinese published data, this paper concludes that there is still leeway to raise existing taxes. The Chinese government should consider conducting some pilot experiments in tobacco tax increases, with some of the new revenues allocated for tobacco control programmes as well as for financing healthcare services among the poor. 


 PMID:9291224

  12. In-beam experience with a highly granular DAQ and control network: TrbNet

    NASA Astrophysics Data System (ADS)

    Michel, J.; Korcyl, G.; Maier, L.; Traxler, M.

    2013-02-01

    Virtually all Data Acquisition Systems (DAQ) for nuclear and particle physics experiments use a large number of Field Programmable Gate Arrays (FPGAs) for data transport and more complex tasks as pattern recognition and data reduction. All these FPGAs in a large system have to share a common state like a trigger number or an epoch counter to keep the system synchronized for a consistent event/epoch building. Additionally, the collected data has to be transported with high bandwidth, optionally via the ubiquitous Ethernet protocol. Furthermore, the FPGAs' internal states and configuration memories have to be accessed for control and monitoring purposes. Another requirement for a modern DAQ-network is the fault-tolerance for intermittent data errors in the form of automatic retransmission of faulty data. As FPGAs suffer from Single Event Effects when exposed to ionizing particles, the system has to deal with failing FPGAs. The TrbNet protocol was developed taking all these requirements into account. Three virtual channels are merged on one physical medium: The trigger/epoch information is transported with the highest priority. The data channel is second in the priority order, while the control channel is the last. Combined with a small frame size of 80 bit this guarantees a low latency data transport: A system with 100 front-ends can be built with a one-way latency of 2.2 us. The TrbNet-protocol was implemented in each of the 550 FPGAs of the HADES upgrade project and has been successfully used during the Au+Au campaign in April 2012. With 2ṡ106/s Au-ions and 3% interaction ratio the accepted trigger rate is 10 kHz while data is written to storage with 150 MBytes/s. Errors are reliably mitigated via the implemented retransmission of packets and auto-shut-down of individual links. TrbNet was also used for full monitoring of the FEE status. The network stack is written in VHDL and was successfully deployed on various Lattice and Xilinx devices. The TrbNet is also

  13. Centralized Monitoring of the Microsoft Windows-based computers of the LHC Experiment Control Systems

    NASA Astrophysics Data System (ADS)

    Varela Rodriguez, F.

    2011-12-01

    The control system of each of the four major Experiments at the CERN Large Hadron Collider (LHC) is distributed over up to 160 computers running either Linux or Microsoft Windows. A quick response to abnormal situations of the computer infrastructure is crucial to maximize the physics usage. For this reason, a tool was developed to supervise, identify errors and troubleshoot such a large system. Although the monitoring of the performance of the Linux computers and their processes was available since the first versions of the tool, it is only recently that the software package has been extended to provide similar functionality for the nodes running Microsoft Windows as this platform is the most commonly used in the LHC detector control systems. In this paper, the architecture and the functionality of the Windows Management Instrumentation (WMI) client developed to provide centralized monitoring of the nodes running different flavour of the Microsoft platform, as well as the interface to the SCADA software of the control systems are presented. The tool is currently being commissioned by the Experiments and it has already proven to be very efficient optimize the running systems and to detect misbehaving processes or nodes.

  14. Spaceflight payload design flight experience G-408

    NASA Technical Reports Server (NTRS)

    Durgin, William W.; Looft, Fred J.; Sacco, Albert, Jr.; Thompson, Robert; Dixon, Anthony G.; Roberti, Dino; Labonte, Robert; Moschini, Larry

    1992-01-01

    Worcester Polytechnic Institute's first payload of spaceflight experiments flew aboard Columbia, STS-40, during June of 1991 and culminated eight years of work by students and faculty. The Get Away Special (GAS) payload was installed on the GAS bridge assembly at the aft end of the cargo bay behind the Spacelab Life Sciences (SLS-1) laboratory. The Experiments were turned on by astronaut signal after reaching orbit and then functioned for 72 hours. Environmental and experimental measurements were recorded on three cassette tapes which, together with zeolite crystals grown on orbit, formed the basis of subsequent analyses. The experiments were developed over a number of years by undergraduate students meeting their project requirements for graduation. The experiments included zeolite crystal growth, fluid behavior, and microgravity acceleration measurement in addition to environmental data acquisition. Preparation also included structural design, thermal design, payload integration, and experiment control. All of the experiments functioned on orbit and the payload system performed within design estimates.

  15. Effects of biochar addition to soil on nitrogen fluxes in a winter wheat lysimeter experiment

    NASA Astrophysics Data System (ADS)

    Hüppi, Roman; Leifeld, Jens; Neftel, Albrecht; Conen, Franz; Six, Johan

    2014-05-01

    Biochar is a carbon-rich, porous residue from pyrolysis of biomass that potentially increases crop yields by reducing losses of nitrogen from soils and/or enhancing the uptake of applied fertiliser by the crops. Previous research is scarce about biochar's ability to increase wheat yields in temperate soils or how it changes nitrogen dynamics in the field. In a lysimeter system with two different soils (sandy/silt loam) nitrogen fluxes were traced by isotopic 15N enriched fertiliser to identify changes in nitrous oxide emissions, leaching and plant uptake after biochar addition. 20t/ha woodchip-waste biochar (pH=13) was applied to these soils in four lysimeters per soil type; the same number of lysimeters served as a control. The soils were cropped with winter wheat during the season 2012/2013. 170 kg-N/ha ammonium nitrate fertiliser with 10% 15N was applied in 3 events during the growing season and 15N concentrations where measured at different points in time in plant, soil, leachate and emitted nitrous oxide. After one year the lysimeter system showed no difference between biochar and control treatment in grain- and straw yield or nitrogen uptake. However biochar did reduce nitrous oxide emissions in the silt loam and losses of nitrate leaching in sandy loam. This study indicates potential reduction of nitrogen loss from cropland soil by biochar application but could not confirm increased yields in an intensive wheat production system.

  16. Using Embryology Screencasts: A Useful Addition to the Student Learning Experience?

    ERIC Educational Resources Information Center

    Evans, Darrell J. R.

    2011-01-01

    Although podcasting has been a well used resource format in the last few years as a way of improving the student learning experience, the inclusion of enhanced audiovisual formats such as screencasts has been less used, despite the advantage that they work well for both visual and auditory learners. This study examines the use of and student…

  17. Controller design approach based on linear programming.

    PubMed

    Tanaka, Ryo; Shibasaki, Hiroki; Ogawa, Hiromitsu; Murakami, Takahiro; Ishida, Yoshihisa

    2013-11-01

    This study explains and demonstrates the design method for a control system with a load disturbance observer. Observer gains are determined by linear programming (LP) in terms of the Routh-Hurwitz stability criterion and the final-value theorem. In addition, the control model has a feedback structure, and feedback gains are determined to be the linear quadratic regulator. The simulation results confirmed that compared with the conventional method, the output estimated by our proposed method converges to a reference input faster when a load disturbance is added to a control system. In addition, we also confirmed the effectiveness of the proposed method by performing an experiment with a DC motor. © 2013 ISA. Published by ISA. All rights reserved.

  18. Analyses of requirements for computer control and data processing experiment subsystems. Volume 1: ATM experiment S-056 image data processing system techniques development

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The solar imaging X-ray telescope experiment (designated the S-056 experiment) is described. It will photograph the sun in the far ultraviolet or soft X-ray region. Because of the imaging characteristics of this telescope and the necessity of using special techniques for capturing images on film at these wave lengths, methods were developed for computer processing of the photographs. The problems of image restoration were addressed to develop and test digital computer techniques for applying a deconvolution process to restore overall S-056 image quality. Additional techniques for reducing or eliminating the effects of noise and nonlinearity in S-056 photographs were developed.

  19. Flight-test experience in digital control of a remotely piloted vehicle.

    NASA Technical Reports Server (NTRS)

    Edwards, J. W.

    1972-01-01

    The development of a remotely piloted vehicle system consisting of a remote pilot cockpit and a ground-based digital computer coupled to the aircraft through telemetry data links is described. The feedback control laws are implemented in a FORTRAN program. Flight-test experience involving high feedback gain limits for attitude and attitude rate feedback variables, filtering of sampled data, and system operation during intermittent telemetry data link loss is discussed. Comparisons of closed-loop flight tests with analytical calculations, and pilot comments on system operation are included.

  20. Evaluation of soil carbon pools after the addition of prunings in subtropical orchards placed in terraces

    NASA Astrophysics Data System (ADS)

    Márquez San Emeterio, Layla; Martín Reyes, Marino Pedro; Ortiz Bernad, Irene; Fernández Ondoño, Emilia; Sierra Aragón, Manuel

    2017-04-01

    The amount of carbon that can be stored in a soil depends on many factors, such as the type of soil, the chemical composition of plant rests and the climate, and is also highly affected by land use and soil management. Agricultural ecosystems are proved to absorb a large amount of CO2 from the atmosphere through several sustainable management practices. In addition, organic materials such as leaves, grass, prunings, etc., comprise a significant type of agricultural practices as a result of waste recycling. The aim of this research was to evaluate the effects of the addition of different organic prunings on the potential for carbon sequestration in agricultural soils placed in terraces. Three subtropical orchards were sampled in Almuñécar (Granada, S Spain): mango (Mangifera indica L.), avocado (Persea americana Mill.) and cherimoya (Annonacherimola Mill.). The predominant climate is Subtropical Mediterranean and the soil is an Eutric Anthrosol. The experimental design consisted in the application of prunings from avocado, cherimoya and mango trees, placed on the surface soil underneath their correspondent trees, as well as garden prunings from the green areas surrounding the town center on the surface soils under the three orchard trees. Control experiences without the addition of prunings were also evaluated. These experiences were followed for three years. Soil samples were taken at4 cm depth. They were dried for 3-4 days and then sieved (<2 mm).Total soil organic C, water-soluble soil organic C, mineral-associated organic C and non-oxidable C were analyzed and expressed as carbon pools (Mg C ha-1for total soil organic C, or Kg C ha-1for the others). The results showed an increase of all organic carbon pools in all pruning treatments compared to the control experiences. Differences in total organic carbon pool were statistically significant between soils under avocado prunings and their control soil, and between soils under garden prunings with cherimoya and

  1. Additional Cultural Resources Investigations at Selected Portions of the State-Road Coulee - Pammel Creek Flood Control Project at La Crosse, Wisconsin

    DTIC Science & Technology

    1986-05-01

    Mammals: Ten mammal taxa are represented in the Lc176 assemblage. Two of these, the short-tailed shrew (Blarina brevivicauda) and a vole (Microtus sp...ADDITIONAL CULTURAL RESOURCES INVESTIGATIONS AT SELECTED PORTIONS OF THE STATE-ROAD COULEE - PAMMEL CREEK FLOOD CONTROL PROJECT ATm LA CROSSE...INVESTIGATIONS AT SELECTED PORTIONS OF THE STATE-ROAD COULEE- PAMMEL CREEK FLOOD CONTROL PROJECT AT LA CROSSE. WISCONSIN 12. PERSONAL AUTHOR(S

  2. Controlling the corrosion and cathodic activation of magnesium via microalloying additions of Ge

    PubMed Central

    Liu, R. L.; Hurley, M. F.; Kvryan, A.; Williams, G.; Scully, J. R.; Birbilis, N.

    2016-01-01

    The evolution of corrosion morphology and kinetics for magnesium (Mg) have been demonstrated to be influenced by cathodic activation, which implies that the rate of the cathodic partial reaction is enhanced as a result of anodic dissolution. This phenomenon was recently demonstrated to be moderated by the use of arsenic (As) alloying as a poison for the cathodic reaction, leading to significantly improved corrosion resistance. The pursuit of alternatives to toxic As is important as a means to imparting a technologically safe and effective corrosion control method for Mg (and its alloys). In this work, Mg was microalloyed with germanium (Ge), with the aim of improving corrosion resistance by retarding cathodic activation. Based on a combined analysis herein, we report that Ge is potent in supressing the cathodic hydrogen evolution reaction (reduction of water) upon Mg, improving corrosion resistance. With the addition of Ge, cathodic activation of Mg subject to cyclic polarisation was also hindered, with beneficial implications for future Mg electrodes. PMID:27350286

  3. On Deviations between Observed and Theoretically Estimated Values on Additivity-Law Failures

    NASA Astrophysics Data System (ADS)

    Nayatani, Yoshinobu; Sobagaki, Hiroaki

    The authors have reported in the previous studies that the average observed results are about a half of the corresponding predictions on the experiments with large additivity-law failures. One of the reasons of the deviations is studied and clarified by using the original observed data on additivity-law failures in the Nakano experiment. The conclusion from the observations and their analyses clarified that it was essentially difficult to have a good agreement between the average observed results and the corresponding theoretical predictions in the experiments with large additivity-law failures. This is caused by a kind of unavoidable psychological pressure existing in subjects participated in the experiments. We should be satisfied with the agreement in trend between them.

  4. Self-reported racism and experience of toothache among pregnant Aboriginal Australians: the role of perceived stress, sense of control, and social support.

    PubMed

    Ben, Jehonathan; Paradies, Yin; Priest, Naomi; Parker, Eleanor Jane; Roberts-Thomson, Kaye F; Lawrence, Herenia P; Broughton, John; Jamieson, Lisa M

    2014-01-01

    We hypothesized that the psychosocial factors perceived stress and sense of personal control mediated the relationship between self-reported racism and experience of toothache. We hypothesized that social support moderated this relationship. Data from 365 pregnant Aboriginal Australian women were used to evaluate experience of toothache, socio-demographic factors, psychosocial factors, general health, risk behaviors, and self-reported racism exposure. Hierarchical logistic regression models estimated odds ratios (ORs) and 95 percent confidence intervals (CIs) for experience of toothache. Perceived stress and sense of personal control were examined as mediators of the association between self-reported racism and experience of toothache. Social support was examined as a moderator. Self-reported racism persisted as a risk indicator for experience of toothache (OR 1.99, 95 percent CI 1.07-3.72) after controlling for age, level of education, and difficulty paying a $100 dental bill. The relationship between self-reported racism and experience of toothache was mediated by sense of control. The direct effect of self-reported racism on experience of toothache became only marginally significant, and the indirect effect was significant (β coefficient=0.04, bias-corrected 95 percent CI 0.004-0.105, 21.2 percent of effect mediated). Stress was insignificant as a mediator. Social support was insignificant as a moderator. The findings indicate that high levels of self-reported racism were associated with experience of toothache and that sense of control, but not perceived stress, mediated the association between self-reported racism and experience of toothache among this sample of pregnant Aboriginal Australian women. Social support did not moderate the association between self-reported racism and experience of toothache. © 2014 American Association of Public Health Dentistry.

  5. External Standards or Standard Addition? Selecting and Validating a Method of Standardization

    NASA Astrophysics Data System (ADS)

    Harvey, David T.

    2002-05-01

    A common feature of many problem-based laboratories in analytical chemistry is a lengthy independent project involving the analysis of "real-world" samples. Students research the literature, adapting and developing a method suitable for their analyte, sample matrix, and problem scenario. Because these projects encompass the complete analytical process, students must consider issues such as obtaining a representative sample, selecting a method of analysis, developing a suitable standardization, validating results, and implementing appropriate quality assessment/quality control practices. Most textbooks and monographs suitable for an undergraduate course in analytical chemistry, however, provide only limited coverage of these important topics. The need for short laboratory experiments emphasizing important facets of method development, such as selecting a method of standardization, is evident. The experiment reported here, which is suitable for an introductory course in analytical chemistry, illustrates the importance of matrix effects when selecting a method of standardization. Students also learn how a spike recovery is used to validate an analytical method, and obtain a practical experience in the difference between performing an external standardization and a standard addition.

  6. Fear of childbirth in expectant fathers, subsequent childbirth experience and impact of antenatal education: subanalysis of results from a randomized controlled trial.

    PubMed

    Bergström, Malin; Rudman, Ann; Waldenström, Ulla; Kieler, Helle

    2013-08-01

    To explore if antenatal fear of childbirth in men affects their experience of the birth event and if this experience is associated with type of childbirth preparation. Data from a randomized controlled multicenter trial on antenatal education. 15 antenatal clinics in Sweden between January 2006 and May 2007. 762 men, of whom 83 (10.9%) suffered from fear of childbirth. Of these 83 men, 39 were randomized to psychoprophylaxis childbirth preparation where men were trained to coach their partners during labor and 44 to standard care antenatal preparation for childbirth and parenthood without such training. Experience of childbirth was compared between men with and without fear of childbirth regardless of randomization, and between fearful men in the randomized groups. Analyses by logistic regression adjusted for sociodemographic variables. Self-reported data on experience of childbirth including an adapted version of the Wijma Delivery Experience Questionnaire (W-DEQ B). Men with antenatal fear of childbirth more often experienced childbirth as frightening than men without fear: adjusted odds ratio 4.68, 95% confidence interval 2.67-8.20. Men with antenatal fear in the psychoprophylaxis group rated childbirth as frightening less often than those in standard care: adjusted odds ratio 0.30, 95% confidence interval 0.10-0.95. Men who suffer from antenatal fear of childbirth are at higher risk of experiencing childbirth as frightening. Childbirth preparation including training as a coach may help fearful men to a more positive childbirth experience. Additional studies are needed to support this conclusion. © 2013 Nordic Federation of Societies of Obstetrics and Gynecology.

  7. Stability and Control Estimation Flight Test Results for the SR-71 Aircraft With Externally Mounted Experiments

    NASA Technical Reports Server (NTRS)

    Moes, Timothy R.; Iliff, Kenneth

    2002-01-01

    A maximum-likelihood output-error parameter estimation technique is used to obtain stability and control derivatives for the NASA Dryden Flight Research Center SR-71A airplane and for configurations that include experiments externally mounted to the top of the fuselage. This research is being done as part of the envelope clearance for the new experiment configurations. Flight data are obtained at speeds ranging from Mach 0.4 to Mach 3.0, with an extensive amount of test points at approximately Mach 1.0. Pilot-input pitch and yaw-roll doublets are used to obtain the data. This report defines the parameter estimation technique used, presents stability and control derivative results, and compares the derivatives for the three configurations tested. The experimental configurations studied generally show acceptable stability, control, trim, and handling qualities throughout the Mach regimes tested. The reduction of directional stability for the experimental configurations is the most significant aerodynamic effect measured and identified as a design constraint for future experimental configurations. This report also shows the significant effects of aircraft flexibility on the stability and control derivatives.

  8. STS-41 Voice Command System Flight Experiment Report

    NASA Technical Reports Server (NTRS)

    Salazar, George A.

    1981-01-01

    This report presents the results of the Voice Command System (VCS) flight experiment on the five-day STS-41 mission. Two mission specialists,Bill Shepherd and Bruce Melnick, used the speaker-dependent system to evaluate the operational effectiveness of using voice to control a spacecraft system. In addition, data was gathered to analyze the effects of microgravity on speech recognition performance.

  9. Research on Mechanisms and Controlling Methods of Macro Defects in TC4 Alloy Fabricated by Wire Additive Manufacturing.

    PubMed

    Ji, Lei; Lu, Jiping; Tang, Shuiyuan; Wu, Qianru; Wang, Jiachen; Ma, Shuyuan; Fan, Hongli; Liu, Changmeng

    2018-06-28

    Wire feeding additive manufacturing (WFAM) has broad application prospects because of its advantages of low cost and high efficiency. However, with the mode of lateral wire feeding, including wire and laser additive manufacturing, gas tungsten arc additive manufacturing etc., it is easy to generate macro defects on the surface of the components because of the anisotropy of melted wire, which limits the promotion and application of WFAM. In this work, gas tungsten arc additive manufacturing with lateral wire feeding is proposed to investigate the mechanisms of macro defects. The results illustrate that the defect forms mainly include side spatters, collapse, poor flatness, and unmelted wire. It was found that the heat input, layer thickness, tool path, and wire curvature can have an impact on the macro defects. Side spatters are the most serious defects, mainly because the droplets cannot be transferred to the center of the molten pool in the lateral wire feeding mode. This research indicates that the macro defects can be controlled by optimizing the process parameters. Finally, block parts without macro defects were fabricated, which is meaningful for the further application of WFAM.

  10. An empirical study of flight control software reliability

    NASA Technical Reports Server (NTRS)

    Dunham, J. R.; Pierce, J. L.

    1986-01-01

    The results of a laboratory experiment in flight control software reliability are reported. The experiment tests a small sample of implementations of a pitch axis control law for a PA28 aircraft with over 14 million pitch commands with varying levels of additive input and feedback noise. The testing which uses the method of n-version programming for error detection surfaced four software faults in one implementation of the control law. The small number of detected faults precluded the conduct of the error burst analyses. The pitch axis problem provides data for use in constructing a model in the prediction of the reliability of software in systems with feedback. The study is undertaken to find means to perform reliability evaluations of flight control software.

  11. The Control of Invasive Knotweed Species (Fallopia sp.). Research Experiences from Austria

    NASA Astrophysics Data System (ADS)

    Lammeranner, Walter; Schmidt, Christina; Eitler, Manuela; Natascha, Steinbauer

    2013-04-01

    The alien plant species Fallopia japonica (Japanese Knotweed), Fallopia sachalinensis (Sakhalin Knotweed) and the clonal knotweed hybrid Fallopia × bohemica are invasive plant species which spread out within Europe. They often form dense stands along Rivers and have negative impacts on biodiversity and ecosystem functioning and also threaten the stability of river banks. Due to their life form, vitality and their enormous ability to regenerate themselves, they are extremely hard to fight. The control measurements against Fallopia species are therefore complicated and often do not have the desired results. Our research tried two approaches to deal with these invasive plant species. The first approach was the use of soil bioengineering techniques which have considerable potential for the management of Fallopia. In our study at the river Schwechat (Lower Austria) we tested two soil bioengineering methods for the control of Fallopia. The first method was the use of living brush mattresses with willows (Salix sp.) to fight the growth of Fallopia species. Within a second method a black liner was used in combination with willow cuttings. After cutting the Fallopia stands the liner was applied to the river bank and fixed with living willow cutting to the surface. The two areas were compared to untreated river bank areas. At several points of time we compared the aboveground response (number of shoots, basal shoot diameters, plant heights, number of stems, aboveground biomass). Additionally the aboveground plant parameters of the willows were measured. In a second approach it was tested if Fallopia can be suppressed or even exterminated if they are submerged for longer time periods. For the experiments Fallopia rhizomes were planted in plastic containers. After a certain growing period, the plants were cut and documented quantitatively by the measurements of shoot lengths, shoot diameters and aboveground biomass. After the first harvest the containers were flooded with

  12. Experience with The Use of Warm Mix Asphalt Additives in Bitumen Binders

    NASA Astrophysics Data System (ADS)

    Cápayová, Silvia; Unčík, Stanislav; Cihlářová, Denisa

    2018-03-01

    In most European countries, Hot Mix Asphalt (HMA) technology is still being used as the standard for the production and processing of bituminous mixtures. However, from the perspective of environmental acceptability, global warming and greenhouse gas production, Slovakia is making an effort to put into practice modern technology, which is characterized by lower energy consumption and reducing negative impacts on the environment. Warm mix asphalt technologies (WMA), which have been verified at the Department of Transportation Engineering laboratory, Faculty of Civil Engineering, Slovak University of Technology (FCE, SUT) can provide the required mixture properties and can be used not only for the construction of new roads, but also for their renovation and reconstruction. The paper was created in cooperation with the Technical University of Ostrava, Czech Republic, which also deals with the addition of additives to asphalt mixtures and binders. It describes a comparison of the impact of some organic and chemical additives on the properties of commonly used bitumen binders in accordance with valid standards and technical regulations.

  13. Respiratory Infections in the U.S. Military: Recent Experience and Control

    PubMed Central

    Cooper, Michael J.; Myers, Christopher A.; Cummings, James F.; Vest, Kelly G.; Russell, Kevin L.; Sanchez, Joyce L.; Hiser, Michelle J.; Gaydos, Charlotte A.

    2015-01-01

    SUMMARY This comprehensive review outlines the impact of military-relevant respiratory infections, with special attention to recruit training environments, influenza pandemics in 1918 to 1919 and 2009 to 2010, and peacetime operations and conflicts in the past 25 years. Outbreaks and epidemiologic investigations of viral and bacterial infections among high-risk groups are presented, including (i) experience by recruits at training centers, (ii) impact on advanced trainees in special settings, (iii) morbidity sustained by shipboard personnel at sea, and (iv) experience of deployed personnel. Utilizing a pathogen-by-pathogen approach, we examine (i) epidemiology, (ii) impact in terms of morbidity and operational readiness, (iii) clinical presentation and outbreak potential, (iv) diagnostic modalities, (v) treatment approaches, and (vi) vaccine and other control measures. We also outline military-specific initiatives in (i) surveillance, (ii) vaccine development and policy, (iii) novel influenza and coronavirus diagnostic test development and surveillance methods, (iv) influenza virus transmission and severity prediction modeling efforts, and (v) evaluation and implementation of nonvaccine, nonpharmacologic interventions. PMID:26085551

  14. Use of Antimicrobial Food Additives as Potential Dipping Solutions to Control Pseudomonas spp. Contamination in the Frankfurters and Ham.

    PubMed

    Oh, Mi-Hwa; Park, Beom-Young; Jo, Hyunji; Lee, Soomin; Lee, Heeyoung; Choi, Kyoung-Hee; Yoon, Yohan

    2014-01-01

    This study evaluated the effect of sodium diacetate and sodium lactate solutions for reducing the cell count of Pseudomonas spp. in frankfurters and hams. A mixture of Pseudomonas aeruginosa (NCCP10338, NCCP10250, and NCCP11229), and Pseudomonas fluorescens (KACC10323 and KACC10326) was inoculated on cooked frankfurters and ham. The inoculated samples were immersed into control (sterile distilled water), sodium diacetate (5 and 10%), sodium lactate (5 and 10%), 5% sodium diacetate + 5% sodium lactate, and 10% sodium diacetate + 10% sodium lactate for 0-10 min. Inoculated frankfurters and ham were also immersed into acidified (pH 3.0) solutions such as acidified sodium diacetate (5 and 10%), and acidified sodium lactate (5 and 10%) in addition to control (acidified distilled water) for 0-10 min. Total aerobic plate counts for Pseudomonas spp. were enumerated on Cetrimide agar. Significant reductions (ca. 2 Log CFU/g) in Pseudomonas spp. cells on frankfurters and ham were observed only for a combination treatment of 10% sodium lactate + 10% sodium diacetate. When the solutions were acidified to pH 3.0, the total reductions of Pseudomonas spp. were 1.5-4.0 Log CFU/g. The order of reduction amounts of Pseudomonas spp. cell counts was 10% sodium lactate > 5% sodium lactate ≥ 10% sodium diacetate > 5% sodium diacetate > control for frankfurters, and 10% sodium lactate > 5% sodium lactate > 10% sodium diacetate > 5% sodium diacetate > control for ham. The results suggest that using acidified food additive antimicrobials, as dipping solutions, should be useful in reducing Pseudomonas spp. on frankfurters and ham.

  15. Quality of surgical randomized controlled trials for acute cholecystitis: assessment based on CONSORT and additional check items.

    PubMed

    Shikata, Satoru; Nakayama, Takeo; Yamagishi, Hisakazu

    2008-01-01

    In this study, we conducted a limited survey of reports of surgical randomized controlled trials, using the consolidated standards of reporting trials (CONSORT) statement and additional check items to clarify problems in the evaluation of surgical reports. A total of 13 randomized trials were selected from two latest review articles on biliary surgery. Each randomized trial was evaluated according to 28 quality measures that comprised items from the CONSORT statement plus additional items. Analysis focused on relationships between the quality of each study and the estimated effect gap ("pooled estimate in meta-analysis" -- "estimated effect of each study"). No definite relationships were found between individual study quality and the estimated effect gap. The following items could have been described but were not provided in almost all the surgical RCT reports: "clearly defined outcomes"; "details of randomization"; "participant flow charts"; "intention-to-treat analysis"; "ancillary analyses"; and "financial conflicts of interest". The item, "participation of a trial methodologist in the study" was not found in any of the reports. Although the quality of reporting trials is not always related to a biased estimation of treatment effect, the items used for quality measures must be described to enable readers to evaluate the quality and applicability of the reporting. Further development of an assessment tool is needed for items specific to surgical randomized controlled trials.

  16. Emollient bath additives for the treatment of childhood eczema (BATHE): multicentre pragmatic parallel group randomised controlled trial of clinical and cost effectiveness

    PubMed Central

    Ridd, Matthew J; Francis, Nick A; Stuart, Beth; Rumsby, Kate; Chorozoglou, Maria; Becque, Taeko; Roberts, Amanda; Liddiard, Lyn; Nollett, Claire; Hooper, Julie; Prude, Martina; Wood, Wendy; Thomas, Kim S; Thomas-Jones, Emma; Williams, Hywel C; Little, Paul

    2018-01-01

    Abstract Objectives To determine the clinical effectiveness and cost effectiveness of including emollient bath additives in the management of eczema in children. Design Pragmatic randomised open label superiority trial with two parallel groups. Setting 96 general practices in Wales and western and southern England. Participants 483 children aged 1 to 11 years, fulfilling UK diagnostic criteria for atopic dermatitis. Children with very mild eczema and children who bathed less than once weekly were excluded. Interventions Participants in the intervention group were prescribed emollient bath additives by their usual clinical team to be used regularly for 12 months. The control group were asked to use no bath additives for 12 months. Both groups continued with standard eczema management, including leave-on emollients, and caregivers were given standardised advice on how to wash participants. Main outcome measures The primary outcome was eczema control measured by the patient oriented eczema measure (POEM, scores 0-7 mild, 8-16 moderate, 17-28 severe) weekly for 16 weeks. Secondary outcomes were eczema severity over one year (monthly POEM score from baseline to 52 weeks), number of eczema exacerbations resulting in primary healthcare consultation, disease specific quality of life (dermatitis family impact), generic quality of life (child health utility-9D), utilisation of resources, and type and quantity of topical corticosteroid or topical calcineurin inhibitors prescribed. Results 483 children were randomised and one child was withdrawn, leaving 482 children in the trial: 51% were girls (244/482), 84% were of white ethnicity (447/470), and the mean age was 5 years. 96% (461/482) of participants completed at least one post-baseline POEM, so were included in the analysis, and 77% (370/482) completed questionnaires for more than 80% of the time points for the primary outcome (12/16 weekly questionnaires to 16 weeks). The mean baseline POEM score was 9.5 (SD 5.7) in the

  17. Assessment of acute toxicity tests and rhizotron experiments to characterize lethal and sublethal control of soil-based pests.

    PubMed

    Agatz, Annika; Schumann, Mario M; French, Bryan W; Brown, Colin D; Vidal, Stefan

    2018-03-24

    Characterizing lethal and sublethal control of soil-based pests with plant protection products is particularly challenging due to the complex and dynamic interplay of the system components. Here, we present two types of studies: acute toxcity experiments (homogenous exposure of individuals in soil) and rhizotron experiments (heterogeneous exposure of individuals in soil) to investigate their ability to strengthen our understanding of mechanisms driving the effectivness of the plant protection product. Experiments were conducted using larvae of the western corn rootworm Diabrotica virgifera LeConte and three pesticide active ingredients: clothianidin (neonicotinoid), chlorpyrifos (organophosphate) and tefluthrin (pyrethroid). The order of compound concentrations needed to invoke a specific effect intensity (EC 50 values) within the acute toxicity tests was chlorpyrifos > tefluthrin > clothianidin. This order changed for the rhizotron experiments because application type, fate and transport of the compounds in the soil profile, and sublethal effects on larvae also influence their effectiveness in controlling larval feeding on corn roots. Beyond the pure measurement of efficacy through observing relative changes in plant injury to control plants, the tests generate mechanistic understanding for drivers of efficacy apart from acute toxicity. The experiments have the potential to enhance efficacy testing and product development, and might be useful tools for assessing resistance development in the future. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  18. Exposure and Experience: Additional Criteria for Selecting Future Operational Theater Commanders

    DTIC Science & Technology

    2009-10-23

    American Civil War, WWII and today ‟s conflict. However, for the scope of this paper, a pattern clearly emerges between service in direct observation of...Kaufmann. From Plato to Derrida . Upper Saddle River, New Jersey: Pearson Prentice Hall, 2008. 8 Experience Comparison of Former...Forrest E., and Walter Kaufmann. From Plato to Derrida . Upper Saddle River, New Jersey: Pearson Prentice Hall, 2008. Bell, William Gardner. Center

  19. Closed-loop control of renal perfusion pressure in physiological experiments.

    PubMed

    Campos-Delgado, D U; Bonilla, I; Rodríguez-Martínez, M; Sánchez-Briones, M E; Ruiz-Hernández, E

    2013-07-01

    This paper presents the design, experimental modeling, and control of a pump-driven renal perfusion pressure (RPP)-regulatory system to implement precise and relatively fast RPP regulation in rats. The mechatronic system is a simple, low-cost, and reliable device to automate the RPP regulation process based on flow-mediated occlusion. Hence, the regulated signal is the RPP measured in the left femoral artery of the rat, and the manipulated variable is the voltage applied to a dc motor that controls the occlusion of the aorta. The control system is implemented in a PC through the LabView software, and a data acquisition board NI USB-6210. A simple first-order linear system is proposed to approximate the dynamics in the experiment. The parameters of the model are chosen to minimize the error between the predicted and experimental output averaged from eight input/output datasets at different RPP operating conditions. A closed-loop servocontrol system based on a pole-placement PD controller plus dead-zone compensation was proposed for this purpose. First, the feedback structure was validated in simulation by considering parameter uncertainty, and constant and time-varying references. Several experimental tests were also conducted to validate in real time the closed-loop performance for stepwise and fast switching references, and the results show the effectiveness of the proposed automatic system to regulate the RPP in the rat, in a precise, accurate (mean error less than 2 mmHg) and relatively fast mode (10-15 s of response time).

  20. Experience with multiple control groups in a large population-based case-control study on genetic and environmental risk factors.

    PubMed

    Pomp, E R; Van Stralen, K J; Le Cessie, S; Vandenbroucke, J P; Rosendaal, F R; Doggen, C J M

    2010-07-01

    We discuss the analytic and practical considerations in a large case-control study that had two control groups; the first control group consisting of partners of patients and the second obtained by random digit dialling (RDD). As an example of the evaluation of a general lifestyle factor, we present body mass index (BMI). Both control groups had lower BMIs than the patients. The distribution in the partner controls was closer to that of the patients, likely due to similar lifestyles. A statistical approach was used to pool the results of both analyses, wherein partners were analyzed with a matched analysis, while RDDs were analyzed without matching. Even with a matched analysis, the odds ratio with partner controls remained closer to unity than with RDD controls, which is probably due to unmeasured confounders in the comparison with the random controls as well as intermediary factors. However, when studying injuries as a risk factor, the odds ratio remained higher with partner control subjects than with RRD control subjects, even after taking the matching into account. Finally we used factor V Leiden as an example of a genetic risk factor. The frequencies of factor V Leiden were identical in both control groups, indicating that for the analyses of this genetic risk factor the two control groups could be combined in a single unmatched analysis. In conclusion, the effect measures with the two control groups were in the same direction, and of the same order of magnitude. Moreover, it was not always the same control group that produced the higher or lower estimates, and a matched analysis did not remedy the differences. Our experience with the intricacies of dealing with two control groups may be useful to others when thinking about an optimal research design or the best statistical approach.

  1. Remote Control and Monitoring of VLBI Experiments by Smartphones

    NASA Astrophysics Data System (ADS)

    Ruztort, C. H.; Hase, H.; Zapata, O.; Pedreros, F.

    2012-12-01

    For the remote control and monitoring of VLBI operations, we developed a software optimized for smartphones. This is a new tool based on a client-server architecture with a Web interface optimized for smartphone screens and cellphone networks. The server uses variables of the Field System and its station specific parameters stored in the shared memory. The client running on the smartphone by a Web interface analyzes and visualizes the current status of the radio telescope, receiver, schedule, and recorder. In addition, it allows commands to be sent remotely to the Field System computer and displays the log entries. The user has full access to the entire operation process, which is important in emergency cases. The software also integrates a webcam interface.

  2. AMO EXPRESS: A Command and Control Experiment for Crew Autonomy

    NASA Technical Reports Server (NTRS)

    Stetson, Howard K.; Frank, Jeremy; Cornelius, Randy; Haddock, Angie; Wang, Lui; Garner, Larry

    2015-01-01

    NASA is investigating a range of future human spaceflight missions, including both Mars-distance and Near Earth Object (NEO) targets. Of significant importance for these missions is the balance between crew autonomy and vehicle automation. As distance from Earth results in increasing communication delays, future crews need both the capability and authority to independently make decisions. However, small crews cannot take on all functions performed by ground today, and so vehicles must be more automated to reduce the crew workload for such missions. NASA's Advanced Exploration Systems Program funded Autonomous Mission Operations (AMO) project conducted an autonomous command and control demonstration of intelligent procedures to automatically initialize a rack onboard the International Space Station (ISS) with power and thermal interfaces, and involving core and payload command and telemetry processing, without support from ground controllers. This autonomous operations capability is enabling in scenarios such as a crew medical emergency, and representative of other spacecraft autonomy challenges. The experiment was conducted using the Expedite the Processing of Experiments for Space Station (EXPRESS) rack 7, which was located in the Port 2 location within the U.S Laboratory onboard the International Space Station (ISS). Activation and deactivation of this facility is time consuming and operationally intensive, requiring coordination of three flight control positions, 47 nominal steps, 57 commands, 276 telemetry checks, and coordination of multiple ISS systems (both core and payload). The autonomous operations concept includes a reduction of the amount of data a crew operator is required to verify during activation or de-activation, as well as integration of procedure execution status and relevant data in a single integrated display. During execution, the auto-procedures provide a step-by-step messaging paradigm and a high level status upon termination. This

  3. Anatomically ordered tapping interferes more with one-digit addition than two-digit addition: a dual-task fMRI study.

    PubMed

    Soylu, Firat; Newman, Sharlene D

    2016-02-01

    Fingers are used as canonical representations for numbers across cultures. In previous imaging studies, it was shown that arithmetic processing activates neural resources that are known to participate in finger movements. Additionally, in one dual-task study, it was shown that anatomically ordered finger tapping disrupts addition and subtraction more than multiplication, possibly due to a long-lasting effect of early finger counting experiences on the neural correlates and organization of addition and subtraction processes. How arithmetic task difficulty and tapping complexity affect the concurrent performance is still unclear. If early finger counting experiences have bearing on the neural correlates of arithmetic in adults, then one would expect anatomically and non-anatomically ordered tapping to have different interference effects, given that finger counting is usually anatomically ordered. To unravel these issues, we studied how (1) arithmetic task difficulty and (2) the complexity of the finger tapping sequence (anatomical vs. non-anatomical ordering) affect concurrent performance and use of key neural circuits using a mixed block/event-related dual-task fMRI design with adult participants. The results suggest that complexity of the tapping sequence modulates interference on addition, and that one-digit addition (fact retrieval), compared to two-digit addition (calculation), is more affected from anatomically ordered tapping. The region-of-interest analysis showed higher left angular gyrus BOLD response for one-digit compared to two-digit addition, and in no-tapping conditions than dual tapping conditions. The results support a specific association between addition fact retrieval and anatomically ordered finger movements in adults, possibly due to finger counting strategies that deploy anatomically ordered finger movements early in the development.

  4. Design of microarray experiments for genetical genomics studies.

    PubMed

    Bueno Filho, Júlio S S; Gilmour, Steven G; Rosa, Guilherme J M

    2006-10-01

    Microarray experiments have been used recently in genetical genomics studies, as an additional tool to understand the genetic mechanisms governing variation in complex traits, such as for estimating heritabilities of mRNA transcript abundances, for mapping expression quantitative trait loci, and for inferring regulatory networks controlling gene expression. Several articles on the design of microarray experiments discuss situations in which treatment effects are assumed fixed and without any structure. In the case of two-color microarray platforms, several authors have studied reference and circular designs. Here, we discuss the optimal design of microarray experiments whose goals refer to specific genetic questions. Some examples are used to illustrate the choice of a design for comparing fixed, structured treatments, such as genotypic groups. Experiments targeting single genes or chromosomic regions (such as with transgene research) or multiple epistatic loci (such as within a selective phenotyping context) are discussed. In addition, microarray experiments in which treatments refer to families or to subjects (within family structures or complex pedigrees) are presented. In these cases treatments are more appropriately considered to be random effects, with specific covariance structures, in which the genetic goals relate to the estimation of genetic variances and the heritability of transcriptional abundances.

  5. 2-D Circulation Control Airfoil Benchmark Experiments Intended for CFD Code Validation

    NASA Technical Reports Server (NTRS)

    Englar, Robert J.; Jones, Gregory S.; Allan, Brian G.; Lin, Johb C.

    2009-01-01

    A current NASA Research Announcement (NRA) project being conducted by Georgia Tech Research Institute (GTRI) personnel and NASA collaborators includes the development of Circulation Control (CC) blown airfoils to improve subsonic aircraft high-lift and cruise performance. The emphasis of this program is the development of CC active flow control concepts for both high-lift augmentation, drag control, and cruise efficiency. A collaboration in this project includes work by NASA research engineers, whereas CFD validation and flow physics experimental research are part of NASA s systematic approach to developing design and optimization tools for CC applications to fixed-wing aircraft. The design space for CESTOL type aircraft is focusing on geometries that depend on advanced flow control technologies that include Circulation Control aerodynamics. The ability to consistently predict advanced aircraft performance requires improvements in design tools to include these advanced concepts. Validation of these tools will be based on experimental methods applied to complex flows that go beyond conventional aircraft modeling techniques. This paper focuses on recent/ongoing benchmark high-lift experiments and CFD efforts intended to provide 2-D CFD validation data sets related to NASA s Cruise Efficient Short Take Off and Landing (CESTOL) study. Both the experimental data and related CFD predictions are discussed.

  6. 'Female condoms give women greater control': a qualitative assessment of the experiences of commercial sex workers in Swaziland.

    PubMed

    Mathenjwa, Thulile; Maharaj, Pranitha

    2012-10-01

    To explore commercial sex workers' experiences with the female condom in Swaziland. This is a qualitative study that draws on two focus group discussions and ten individual in-depth interviews with female commercial sex workers in Lavumisa, Swaziland. The findings suggest that the majority of female sex workers prefer to use the female condom with their clients because it offers them greater control over the sexual encounter. Other factors that facilitate its use include the absence of side effects, the enhancement of sexual pleasure and protection against the risk of STIs (including HIV). In addition, the women reported that the female condom is stronger and more resistant to breakage than the male condom. Moreover, the female condoms can be inserted well in advance of sexual intercourse. Difficulties of insertion, partner objection and limited product availability were some of the barriers to the use of the device. There was also a tendency to reuse the female condoms because of lack of product availability and privacy to insert it. Although female condom use involves negotiation with clients, the fact that it offers sex workers an independent method of protection gives them more power and also, increases their ability to control their sexual and reproductive health.

  7. Species Composition and Fire: Non-Additive Mixture Effects on Ground Fuel Flammability

    PubMed Central

    van Altena, Cassandra; van Logtestijn, Richard S. P.; Cornwell, William K.; Cornelissen, Johannes H. C.

    2012-01-01

    Diversity effects on many aspects of ecosystem function have been well documented. However, fire is an exception: fire experiments have mainly included single species, bulk litter, or vegetation, and, as such, the role of diversity as a determinant of flammability, a crucial aspect of ecosystem function, is poorly understood. This study is the first to experimentally test whether flammability characteristics of two-species mixtures are non-additive, i.e., differ from expected flammability based on the component species in monospecific fuel. In standardized fire experiments on ground fuels, including monospecific fuels and mixtures of five contrasting subarctic plant fuel types in a controlled laboratory environment, we measured flame speed, flame duration, and maximum temperature. Broadly half of the mixture combinations showed non-additive effects for these flammability indicators; these were mainly enhanced dominance effects for temporal dynamics – fire speed and duration. Fuel types with the more flammable value for a characteristic determined the rate of fire speed and duration of the whole mixture; in contrast, maximum temperature of the fire was determined by the biomass-weighted mean of the mixture. These results suggest that ecological invasions by highly flammable species may have effects on ground-fire dynamics well out of proportion to their biomass. PMID:22639656

  8. Versatile single-chip event sequencer for atomic physics experiments

    NASA Astrophysics Data System (ADS)

    Eyler, Edward

    2010-03-01

    A very inexpensive dsPIC microcontroller with internal 32-bit counters is used to produce a flexible timing signal generator with up to 16 TTL-compatible digital outputs, with a time resolution and accuracy of 50 ns. This time resolution is easily sufficient for event sequencing in typical experiments involving cold atoms or laser spectroscopy. This single-chip device is capable of triggered operation and can also function as a sweeping delay generator. With one additional chip it can also concurrently produce accurately timed analog ramps, and another one-chip addition allows real-time control from an external computer. Compared to an FPGA-based digital pattern generator, this design is slower but simpler and more flexible, and it can be reprogrammed using ordinary `C' code without special knowledge. I will also describe the use of the same microcontroller with additional hardware to implement a digital lock-in amplifier and PID controller for laser locking, including a simple graphics-based control unit. This work is supported in part by the NSF.

  9. Additive manufacturing of tunable lenses

    NASA Astrophysics Data System (ADS)

    Schlichting, Katja; Novak, Tobias; Heinrich, Andreas

    2017-02-01

    Individual additive manufacturing of optical systems based on 3D Printing offers varied possibilities in design and usage. In addition to the additive manufacturing procedure, the usage of tunable lenses allows further advantages for intelligent optical systems. Our goal is to bring the advantages of additive manufacturing together with the huge potential of tunable lenses. We produced tunable lenses as a bundle without any further processing steps, like polishing. The lenses were designed and directly printed with a 3D Printer as a package. The design contains the membrane as an optical part as well as the mechanical parts of the lens, like the attachments for the sleeves which contain the oil. The dynamic optical lenses were filled with an oil. The focal length of the lenses changes due to a change of the radius of curvature. This change is caused by changing the pressure in the inside of the lens. In addition to that, we designed lenses with special structures to obtain different areas with an individual optical power. We want to discuss the huge potential of this technology for several applications. Further, an appropriate controlling system is needed. Wéll show the possibilities to control and regulate the optical power of the lenses. The lenses could be used for illumination tasks, and in the future, for individual measurement tasks. The main advantage is the individuality and the possibility to create an individual design which completely fulfills the requirements for any specific application.

  10. Childhood Abuse Experiences and the COMT and MTHFR Genetic Variants Associated With Male Sexual Orientation in the Han Chinese Populations: A Case-Control Study.

    PubMed

    Qin, Jia-Bi; Zhao, Guang-Lu; Wang, Feng; Cai, Yu-Mao; Lan, Li-Na; Yang, Lin; Feng, Tie-Jian

    2018-01-01

    Although it is widely acknowledged that genetic and environmental factors are involved in the development of male homosexuality, the causes are not fully understood. To explore the association and interaction of childhood abuse experiences and genetic variants of the catechol-O-methyltransferase (COMT) and methylenetetrahydrofolate reductase (MTHFR) genes with the development of male homosexuality. A case-control study of 537 exclusively homosexual men and 583 exclusively heterosexual men was conducted, with data collected from March 2013 to August 2015. Data were analyzed using χ 2 tests and logistic regression models. Sociodemographic characteristics, childhood abuse experiences, and polymorphisms of COMT at rs4680, rs4818, and rs6267 and MTHFR at rs1801133. More frequent occurrence of physical (adjusted odds ratio [aOR] = 1.78), emotional (aOR = 2.07), and sexual (aOR = 2.53) abuse during childhood was significantly associated with the development of male homosexuality. The polymorphisms of MTHFR at rs1801133 and COMT at rs4818 also were significantly associated with the development of male homosexuality in the homozygote comparisons (T/T vs C/C at rs1801133, aOR = 1.68; G/G vs C/C at rs4818, aOR = 1.75). In addition, significant interaction effects between childhood abuse experiences and the COMT and MTHFR genetic variants on the development of male homosexuality were found. This is the first time that an association of childhood abuse, COMT and MTHFR genetic variants, and their interactions with development of male homosexuality was exhaustively explored, which could help provide new insight into the etiology of male homosexuality. Because homosexual men are a relatively obscure population, it was impossible to select the study participants by random sampling, which could lead to selection bias. In addition, because this was a case-control study, recall bias was inevitable, and we could not verify causality. Childhood abuse and the COMT and MTHFR genetic

  11. Architecture of a general purpose embedded Slow-Control Adapter ASIC for future high-energy physics experiments

    NASA Astrophysics Data System (ADS)

    Gabrielli, Alessandro; Loddo, Flavio; Ranieri, Antonio; De Robertis, Giuseppe

    2008-10-01

    This work is aimed at defining the architecture of a new digital ASIC, namely Slow-Control Adapter (SCA), which will be designed in a commercial 130-nm CMOS technology. This chip will be embedded within a high-speed data acquisition optical link (GBT) to control and monitor the front-end electronics in future high-energy physics experiments. The GBT link provides a transparent transport layer between the SCA and control electronics in the counting room. The proposed SCA supports a variety of common bus protocols to interface with end-user general-purpose electronics. Between the GBT and the SCA a standard 100 Mb/s IEEE-802.3 compatible protocol will be implemented. This standard protocol allows off-line tests of the prototypes using commercial components that support the same standard. The project is justified because embedded applications in modern large HEP experiments require particular care to assure the lowest possible power consumption, still offering the highest reliability demanded by very large particle detectors.

  12. Experiments in advanced control concepts for space robotics - An overview of the Stanford Aerospace Robotics Laboratory

    NASA Technical Reports Server (NTRS)

    Hollars, M. G.; Cannon, R. H., Jr.; Alexander, H. L.; Morse, D. F.

    1987-01-01

    The Stanford University Aerospace Robotics Laboratory is actively developing and experimentally testing advanced robot control strategies for space robotic applications. Early experiments focused on control of very lightweight one-link manipulators and other flexible structures. The results are being extended to position and force control of mini-manipulators attached to flexible manipulators and multilink manipulators with flexible drive trains. Experimental results show that end-point sensing and careful dynamic modeling or adaptive control are key to the success of these control strategies. Free-flying space robot simulators that operate on an air cushion table have been built to test control strategies in which the dynamics of the base of the robot and the payload are important.

  13. Optically Isolated Control of the MOCHI LabJet High Power Pulsed Plasma Experiment

    NASA Astrophysics Data System (ADS)

    Carroll, Evan; Quinley, Morgan; von der Linden, Jens; You, Setthivoine

    2014-10-01

    The MOCHI LabJet experiment designed to investigate the dynamics of astrophysical jets at the University of Washington, requires high energy pulsed power supplies for plasma generation and sustainment. Two 600 μ F, 10 kV DC, pulse forming, power supplies have been specifically developed for this application. For safe and convenient user operation, the power supplies are controlled remotely with optical isolation. Three input voltage signals are required for relay actuation, adjusting bank charging voltage, and to fire the experiment: long duration DC signals, long duration user adjustable DC signals and fast trigger pulses with < μ s rise times. These voltage signals are generated from National Instruments timing cards via LabVIEW and are converted to optical signals by coupling photodiodes with custom electronic circuits. At the experiment, the optical signals are converted back to usable voltage signals using custom circuits. These custom circuits and experimental set-up are presented. This work is supported by US DOE Grant DE-SC0010340.

  14. The EMIR experience in the use of software control simulators to speed up the time to telescope

    NASA Astrophysics Data System (ADS)

    Lopez Ramos, Pablo; López-Ruiz, J. C.; Moreno Arce, Heidy; Rosich, Josefina; Perez Menor, José Maria

    2012-09-01

    One of the main problems facing development teams working on instrument control systems consists on the need to access mechanisms which are not available until well into the integration phase. The need to work with real hardware creates additional problems like, among others: certain faults cannot be tested due to the possibility of hardware damage, taking the system to the limit may shorten its operational lifespan and the full system may not be available during some periods due to maintenance and/or testing of individual components. These problems can be treated with the use of simulators and by applying software/hardware standards. Since information on the construction and performance of electro-mechanical systems is available at relatively early stages of the project, simulators are developed in advance (before the existence of the mechanism) or, if conventions and standards have been correctly followed, a previously developed simulator might be used. This article describes our experience in building software simulators and the main advantages we have identified, which are: the control software can be developed even in the absence of real hardware, critical tests can be prepared using the simulated systems, test system behavior for hardware failure situations that represent a risk of the real system, and the speed up of in house integration of the entire instrument. The use of simulators allows us to reduce development, testing and integration time.

  15. Adaptive Augmenting Control Flight Characterization Experiment on an F/A-18

    NASA Technical Reports Server (NTRS)

    VanZwieten, Tannen S.; Gilligan, Eric T.; Wall, John H.; Orr, Jeb S.; Miller, Christopher J.; Hanson, Curtis E.

    2014-01-01

    The NASA Marshall Space Flight Center (MSFC) Flight Mechanics and Analysis Division developed an Adaptive Augmenting Control (AAC) algorithm for launch vehicles that improves robustness and performance by adapting an otherwise welltuned classical control algorithm to unexpected environments or variations in vehicle dynamics. This AAC algorithm is currently part of the baseline design for the SLS Flight Control System (FCS), but prior to this series of research flights it was the only component of the autopilot design that had not been flight tested. The Space Launch System (SLS) flight software prototype, including the adaptive component, was recently tested on a piloted aircraft at Dryden Flight Research Center (DFRC) which has the capability to achieve a high level of dynamic similarity to a launch vehicle. Scenarios for the flight test campaign were designed specifically to evaluate the AAC algorithm to ensure that it is able to achieve the expected performance improvements with no adverse impacts in nominal or nearnominal scenarios. Having completed the recent series of flight characterization experiments on DFRC's F/A-18, the AAC algorithm's capability, robustness, and reproducibility, have been successfully demonstrated. Thus, the entire SLS control architecture has been successfully flight tested in a relevant environment. This has increased NASA's confidence that the autopilot design is ready to fly on the SLS Block I vehicle and will exceed the performance of previous architectures.

  16. Experience in the installation of a microprocessor system for controlling converter units of the Vyborg substation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gusakovskii, K. B.; Zmaznov, E. Yu.; Katantsev, S. V.

    The experience in the installation of modern digital systems for controlling converter units at the Vyborg converter substation on the basis of advanced microprocessor devices is considered. It is shown that debugging of a control and protection system on mathematical and physical models does not guarantee optimum control of actual converter devices. Examples of advancing the control and protection system are described, the necessity for which has become obvious in tests of actual equipment. Comparison of oscillograms of processes before optimization of the control system and after its optimization and adjustment shows that the digital control system makes it possiblemore » to improve substantially the algorithms of control and protection in the short term and without changing the hardware component.« less

  17. Community Knowledge and Experience of Mosquitoes and Personal Prevention and Control Practices in Lhasa, Tibet

    PubMed Central

    Liu, Xiaobo; Wan, Fangjun; Cirendunzhu; Cirenwangla; Bai, Li; Pengcuociren; Zhou, Lin; Baimaciwang; Guo, Yuhong; Dazhen; Xu, Junfang; Sang, Shaowei; Li, Xiaolu; Gu, Shaohua; Wu, Haixia; Wang, Jun; Dawa; Xiraoruodeng; Liu, Qiyong

    2014-01-01

    Since 2009, great public attention has been paid in Lhasa City (Tibet, China) to mosquito bites and accompanying inflammatory complications. However, the potential contribution of knowledge levels, experiences, disease control and preventive practices (KEP) towards mosquitoes has not received much attention. To investigate community KEP concerning mosquitoes in Lhasa, a cross-sectional survey was undertaken in four sub-districts of urban Lhasa in 2012. Questionnaires were designed to collect information regarding socio-demographics and KEP concerning the harmful effects of mosquitoes on participants. The scoring for KEP was developed after consultation of literature. A total of 591 eligible questionnaires were examined. The majority of respondents were female (61.8%) with a mean age of 46 years. Nearly all of the respondents were of Tibetan nationality (97.4%) and living in registered native households (92.7%), who have less than primary school education. The averages of overall score, knowledge score, experience score, and practice score were 9.23, 4.53, 1.80, 2.90, respectively. The registered household with the highest overall score, knowledge score and practice score was non-native. Female subjects with monthly incomes between 1000 and 3000 RMB had higher experience scores. The correlation analysis revealed that significant positive linear correlations existed between knowledge and experience, knowledge and practices, and experience and practices towards mosquitoes. Past experiences with mosquitoes can result in a better knowledge of effective mosquito control practices in the present and the future. Though the average of overall scores related to mosquitoes is high among the participants in Lhasa, however, the knowledge about the ecological habits of mosquitoes should be strengthened. The findings in this study may help to develop strategies and measures of mosquito and mosquito-borne diseases in the future, not only in Lhasa, but also in similar altitude

  18. Community knowledge and experience of mosquitoes and personal prevention and control practices in Lhasa, Tibet.

    PubMed

    Liu, Xiaobo; Wan, Fangjun; Cirendunzhu; Cirenwangla; Bai, Li; Pengcuociren; Zhou, Lin; Baimaciwang; Guo, Yuhong; Dazhen; Xu, Junfang; Sang, Shaowei; Li, Xiaolu; Gu, Shaohua; Wu, Haixia; Wang, Jun; Dawa; Xiraoruodeng; Liu, Qiyong

    2014-09-23

    Since 2009, great public attention has been paid in Lhasa City (Tibet, China) to mosquito bites and accompanying inflammatory complications. However, the potential contribution of knowledge levels, experiences, disease control and preventive practices (KEP) towards mosquitoes has not received much attention. To investigate community KEP concerning mosquitoes in Lhasa, a cross-sectional survey was undertaken in four sub-districts of urban Lhasa in 2012. Questionnaires were designed to collect information regarding socio-demographics and KEP concerning the harmful effects of mosquitoes on participants. The scoring for KEP was developed after consultation of literature. A total of 591 eligible questionnaires were examined. The majority of respondents were female (61.8%) with a mean age of 46 years. Nearly all of the respondents were of Tibetan nationality (97.4%) and living in registered native households (92.7%), who have less than primary school education. The averages of overall score, knowledge score, experience score, and practice score were 9.23, 4.53, 1.80, 2.90, respectively. The registered household with the highest overall score, knowledge score and practice score was non-native. Female subjects with monthly incomes between 1000 and 3000 RMB had higher experience scores. The correlation analysis revealed that significant positive linear correlations existed between knowledge and experience, knowledge and practices, and experience and practices towards mosquitoes. Past experiences with mosquitoes can result in a better knowledge of effective mosquito control practices in the present and the future. Though the average of overall scores related to mosquitoes is high among the participants in Lhasa, however, the knowledge about the ecological habits of mosquitoes should be strengthened. The findings in this study may help to develop strategies and measures of mosquito and mosquito-borne diseases in the future, not only in Lhasa, but also in similar altitude

  19. Controls Astrophysics and Structures Experiment in Space (CASES) advanced studies and planning

    NASA Technical Reports Server (NTRS)

    Wu, S. T.

    1989-01-01

    The CASES (Controls, Astrophysics, and Structures Experiment in Space) program consists of a flight demonstration of CSI (Controls-Structures Interactions) technology on the Space Shuttle. The basis structure consists of a 32 m deployable boom with actuators and sensors distributed along its length. Upon deployment from the Orbiter bay, the CASES structure will be characterized dynamically and its deformations controlled by a series of experimental control laws; and cold gas thrusters at its tip will be used to orient the Orbiter to a fixed celestial reference. The scientific observations will consist of hard x-ray imaging, at high resolution, of the Sun and the Galactic center. The hard x-ray observations require stable (few arc min) pointing at these targets for one or more position-sensitive proportional counters in the Orbiter bay, which view the object to be imaged through an aperture-encoding mask at the boom tip. This report gives the concensus developed at the second CASES Science Working Group meeting, which took place at NASA Marshall Space Flight Center May 16-17, 1990. An earlier paper and scientific summaries are available and form the basis for the present discussion.

  20. The controllability of the aeroassist flight experiment atmospheric skip trajectory

    NASA Technical Reports Server (NTRS)

    Wood, R.

    1989-01-01

    The Aeroassist Flight Experiment (AFE) will be the first vehicle to simulate a return from geosynchronous orbit, deplete energy during an aerobraking maneuver, and navigate back out of the atmosphere to a low earth orbit It will gather scientific data necessary for future Aeroasisted Orbitl Transfer Vehicles (AOTV's). Critical to mission success is the ability of the atmospheric guidance to accurately attain a targeted post-aeropass orbital apogee while nulling inclination errors and compensating for dispersions in state, aerodynamic, and atmospheric parameters. In typing to satisfy mission constraints, atmospheric entry-interface (EI) conditions, guidance gains, and trajectory. The results of the investigation are presented; emphasizing the adverse effects of dispersed atmospheres on trajectory controllability.